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authorParménides GV <parmegv@sdf.org>2014-06-11 11:56:59 +0200
committerParménides GV <parmegv@sdf.org>2014-06-11 19:50:54 +0200
commit3e121542d8b7ab5201c47bbd3ba5611a23c54759 (patch)
treea6035639e7baa88dd122d0d4e85791726606389a /app/snappy
parentac69881af1b7bfcdd185989f3e434556b1d62fed (diff)
Correctly connects to millipede.
Location keyword on android.cfg isn't supported, EIP corresponding code has been commented out. I think we should support it in ics-openvpn, so that we can show the location instead of the server name. I've updated all opensssl, openvpn, etc. subprojects from rev 813 of ics-openvpn, and jni too.
Diffstat (limited to 'app/snappy')
-rw-r--r--app/snappy/Android.mk35
-rw-r--r--app/snappy/COPYING28
-rw-r--r--app/snappy/conf/config.h129
-rw-r--r--app/snappy/snappy-c.cc90
-rw-r--r--app/snappy/snappy-c.h138
-rw-r--r--app/snappy/snappy-internal.h150
-rw-r--r--app/snappy/snappy-sinksource.cc71
-rw-r--r--app/snappy/snappy-sinksource.h137
-rw-r--r--app/snappy/snappy-stubs-internal.cc42
-rw-r--r--app/snappy/snappy-stubs-internal.h491
-rw-r--r--app/snappy/snappy-stubs-public.h85
-rw-r--r--app/snappy/snappy-stubs-public.h.in85
-rw-r--r--app/snappy/snappy-test.cc606
-rw-r--r--app/snappy/snappy-test.h580
-rw-r--r--app/snappy/snappy.cc1119
-rw-r--r--app/snappy/snappy.h163
-rw-r--r--app/snappy/snappy_unittest.cc1164
17 files changed, 5113 insertions, 0 deletions
diff --git a/app/snappy/Android.mk b/app/snappy/Android.mk
new file mode 100644
index 00000000..cdd26003
--- /dev/null
+++ b/app/snappy/Android.mk
@@ -0,0 +1,35 @@
+
+LOCAL_PATH:= $(call my-dir)
+
+
+common_SRC_FILES:= \
+ snappy-c.cc \
+ snappy-sinksource.cc \
+ snappy-stubs-internal.cc \
+ snappy.cc
+
+common_C_INCLUDES += $(LOCAL_PATH)/ $(LOCAL_PATH)/conf
+
+# static library
+# =====================================================
+
+include $(CLEAR_VARS)
+LOCAL_CPP_EXTENSION := .cc
+LOCAL_SRC_FILES:= $(common_SRC_FILES)
+LOCAL_C_INCLUDES:= $(common_C_INCLUDES)
+LOCAL_MODULE := snappy-static
+LOCAL_PRELINK_MODULE:= false
+LOCAL_MODULE_TAGS := optional
+include $(BUILD_STATIC_LIBRARY)
+
+# dynamic library
+# =====================================================
+
+# include $(CLEAR_VARS)
+# LOCAL_SRC_FILES:= $(common_SRC_FILES)
+# LOCAL_C_INCLUDES:= $(common_C_INCLUDES)
+# LOCAL_MODULE := liblzo
+# LOCAL_PRELINK_MODULE:= false
+# LOCAL_MODULE_TAGS := optional
+# include $(BUILD_SHARED_LIBRARY)
+
diff --git a/app/snappy/COPYING b/app/snappy/COPYING
new file mode 100644
index 00000000..8d6bd9fe
--- /dev/null
+++ b/app/snappy/COPYING
@@ -0,0 +1,28 @@
+Copyright 2011, Google Inc.
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+ * Redistributions of source code must retain the above copyright
+notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following disclaimer
+in the documentation and/or other materials provided with the
+distribution.
+ * Neither the name of Google Inc. nor the names of its
+contributors may be used to endorse or promote products derived from
+this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
diff --git a/app/snappy/conf/config.h b/app/snappy/conf/config.h
new file mode 100644
index 00000000..e0bf3214
--- /dev/null
+++ b/app/snappy/conf/config.h
@@ -0,0 +1,129 @@
+/* config.h. Generated from config.h.in by configure. */
+/* config.h.in. Generated from configure.ac by autoheader. */
+
+/* Define if building universal (internal helper macro) */
+/* #undef AC_APPLE_UNIVERSAL_BUILD */
+
+/* Define to 1 if the compiler supports __builtin_ctz and friends. */
+#define HAVE_BUILTIN_CTZ 1
+
+/* Define to 1 if the compiler supports __builtin_expect. */
+#define HAVE_BUILTIN_EXPECT 1
+
+/* Define to 1 if you have the <byteswap.h> header file. */
+/* #undef HAVE_BYTESWAP_H */
+
+/* Define to 1 if you have the <dlfcn.h> header file. */
+#define HAVE_DLFCN_H 1
+
+/* Use the gflags package for command-line parsing. */
+/* #undef HAVE_GFLAGS */
+
+/* Defined when Google Test is available. */
+/* #undef HAVE_GTEST */
+
+/* Define to 1 if you have the <inttypes.h> header file. */
+#define HAVE_INTTYPES_H 1
+
+/* Define to 1 if you have the `fastlz' library (-lfastlz). */
+/* #undef HAVE_LIBFASTLZ */
+
+/* Define to 1 if you have the `lzf' library (-llzf). */
+/* #undef HAVE_LIBLZF */
+
+/* Define to 1 if you have the `lzo2' library (-llzo2). */
+/* #undef HAVE_LIBLZO2 */
+
+/* Define to 1 if you have the `quicklz' library (-lquicklz). */
+/* #undef HAVE_LIBQUICKLZ */
+
+/* Define to 1 if you have the `z' library (-lz). */
+#define HAVE_LIBZ 1
+
+/* Define to 1 if you have the <memory.h> header file. */
+#define HAVE_MEMORY_H 1
+
+/* Define to 1 if you have the <stddef.h> header file. */
+#define HAVE_STDDEF_H 1
+
+/* Define to 1 if you have the <stdint.h> header file. */
+#define HAVE_STDINT_H 1
+
+/* Define to 1 if you have the <stdlib.h> header file. */
+#define HAVE_STDLIB_H 1
+
+/* Define to 1 if you have the <strings.h> header file. */
+#define HAVE_STRINGS_H 1
+
+/* Define to 1 if you have the <string.h> header file. */
+#define HAVE_STRING_H 1
+
+/* Define to 1 if you have the <sys/byteswap.h> header file. */
+/* #undef HAVE_SYS_BYTESWAP_H */
+
+/* Define to 1 if you have the <sys/endian.h> header file. */
+/* #undef HAVE_SYS_ENDIAN_H */
+
+/* Define to 1 if you have the <sys/mman.h> header file. */
+#define HAVE_SYS_MMAN_H 1
+
+/* Define to 1 if you have the <sys/resource.h> header file. */
+#define HAVE_SYS_RESOURCE_H 1
+
+/* Define to 1 if you have the <sys/stat.h> header file. */
+#define HAVE_SYS_STAT_H 1
+
+/* Define to 1 if you have the <sys/time.h> header file. */
+#define HAVE_SYS_TIME_H 1
+
+/* Define to 1 if you have the <sys/types.h> header file. */
+#define HAVE_SYS_TYPES_H 1
+
+/* Define to 1 if you have the <unistd.h> header file. */
+#define HAVE_UNISTD_H 1
+
+/* Define to 1 if you have the <windows.h> header file. */
+/* #undef HAVE_WINDOWS_H */
+
+/* Define to the sub-directory in which libtool stores uninstalled libraries.
+ */
+#define LT_OBJDIR ".libs/"
+
+/* Name of package */
+#define PACKAGE "snappy"
+
+/* Define to the address where bug reports for this package should be sent. */
+#define PACKAGE_BUGREPORT ""
+
+/* Define to the full name of this package. */
+#define PACKAGE_NAME "snappy"
+
+/* Define to the full name and version of this package. */
+#define PACKAGE_STRING "snappy 1.1.0"
+
+/* Define to the one symbol short name of this package. */
+#define PACKAGE_TARNAME "snappy"
+
+/* Define to the home page for this package. */
+#define PACKAGE_URL ""
+
+/* Define to the version of this package. */
+#define PACKAGE_VERSION "1.1.0"
+
+/* Define to 1 if you have the ANSI C header files. */
+#define STDC_HEADERS 1
+
+/* Version number of package */
+#define VERSION "1.1.0"
+
+/* Define WORDS_BIGENDIAN to 1 if your processor stores words with the most
+ significant byte first (like Motorola and SPARC, unlike Intel). */
+#if defined AC_APPLE_UNIVERSAL_BUILD
+# if defined __BIG_ENDIAN__
+# define WORDS_BIGENDIAN 1
+# endif
+#else
+# ifndef WORDS_BIGENDIAN
+/* # undef WORDS_BIGENDIAN */
+# endif
+#endif
diff --git a/app/snappy/snappy-c.cc b/app/snappy/snappy-c.cc
new file mode 100644
index 00000000..473a0b09
--- /dev/null
+++ b/app/snappy/snappy-c.cc
@@ -0,0 +1,90 @@
+// Copyright 2011 Martin Gieseking <martin.gieseking@uos.de>.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "snappy.h"
+#include "snappy-c.h"
+
+extern "C" {
+
+snappy_status snappy_compress(const char* input,
+ size_t input_length,
+ char* compressed,
+ size_t *compressed_length) {
+ if (*compressed_length < snappy_max_compressed_length(input_length)) {
+ return SNAPPY_BUFFER_TOO_SMALL;
+ }
+ snappy::RawCompress(input, input_length, compressed, compressed_length);
+ return SNAPPY_OK;
+}
+
+snappy_status snappy_uncompress(const char* compressed,
+ size_t compressed_length,
+ char* uncompressed,
+ size_t* uncompressed_length) {
+ size_t real_uncompressed_length;
+ if (!snappy::GetUncompressedLength(compressed,
+ compressed_length,
+ &real_uncompressed_length)) {
+ return SNAPPY_INVALID_INPUT;
+ }
+ if (*uncompressed_length < real_uncompressed_length) {
+ return SNAPPY_BUFFER_TOO_SMALL;
+ }
+ if (!snappy::RawUncompress(compressed, compressed_length, uncompressed)) {
+ return SNAPPY_INVALID_INPUT;
+ }
+ *uncompressed_length = real_uncompressed_length;
+ return SNAPPY_OK;
+}
+
+size_t snappy_max_compressed_length(size_t source_length) {
+ return snappy::MaxCompressedLength(source_length);
+}
+
+snappy_status snappy_uncompressed_length(const char *compressed,
+ size_t compressed_length,
+ size_t *result) {
+ if (snappy::GetUncompressedLength(compressed,
+ compressed_length,
+ result)) {
+ return SNAPPY_OK;
+ } else {
+ return SNAPPY_INVALID_INPUT;
+ }
+}
+
+snappy_status snappy_validate_compressed_buffer(const char *compressed,
+ size_t compressed_length) {
+ if (snappy::IsValidCompressedBuffer(compressed, compressed_length)) {
+ return SNAPPY_OK;
+ } else {
+ return SNAPPY_INVALID_INPUT;
+ }
+}
+
+} // extern "C"
diff --git a/app/snappy/snappy-c.h b/app/snappy/snappy-c.h
new file mode 100644
index 00000000..c6c2a860
--- /dev/null
+++ b/app/snappy/snappy-c.h
@@ -0,0 +1,138 @@
+/*
+ * Copyright 2011 Martin Gieseking <martin.gieseking@uos.de>.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *
+ * * Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above
+ * copyright notice, this list of conditions and the following disclaimer
+ * in the documentation and/or other materials provided with the
+ * distribution.
+ * * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ * Plain C interface (a wrapper around the C++ implementation).
+ */
+
+#ifndef UTIL_SNAPPY_OPENSOURCE_SNAPPY_C_H_
+#define UTIL_SNAPPY_OPENSOURCE_SNAPPY_C_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <stddef.h>
+
+/*
+ * Return values; see the documentation for each function to know
+ * what each can return.
+ */
+typedef enum {
+ SNAPPY_OK = 0,
+ SNAPPY_INVALID_INPUT = 1,
+ SNAPPY_BUFFER_TOO_SMALL = 2
+} snappy_status;
+
+/*
+ * Takes the data stored in "input[0..input_length-1]" and stores
+ * it in the array pointed to by "compressed".
+ *
+ * <compressed_length> signals the space available in "compressed".
+ * If it is not at least equal to "snappy_max_compressed_length(input_length)",
+ * SNAPPY_BUFFER_TOO_SMALL is returned. After successful compression,
+ * <compressed_length> contains the true length of the compressed output,
+ * and SNAPPY_OK is returned.
+ *
+ * Example:
+ * size_t output_length = snappy_max_compressed_length(input_length);
+ * char* output = (char*)malloc(output_length);
+ * if (snappy_compress(input, input_length, output, &output_length)
+ * == SNAPPY_OK) {
+ * ... Process(output, output_length) ...
+ * }
+ * free(output);
+ */
+snappy_status snappy_compress(const char* input,
+ size_t input_length,
+ char* compressed,
+ size_t* compressed_length);
+
+/*
+ * Given data in "compressed[0..compressed_length-1]" generated by
+ * calling the snappy_compress routine, this routine stores
+ * the uncompressed data to
+ * uncompressed[0..uncompressed_length-1].
+ * Returns failure (a value not equal to SNAPPY_OK) if the message
+ * is corrupted and could not be decrypted.
+ *
+ * <uncompressed_length> signals the space available in "uncompressed".
+ * If it is not at least equal to the value returned by
+ * snappy_uncompressed_length for this stream, SNAPPY_BUFFER_TOO_SMALL
+ * is returned. After successful decompression, <uncompressed_length>
+ * contains the true length of the decompressed output.
+ *
+ * Example:
+ * size_t output_length;
+ * if (snappy_uncompressed_length(input, input_length, &output_length)
+ * != SNAPPY_OK) {
+ * ... fail ...
+ * }
+ * char* output = (char*)malloc(output_length);
+ * if (snappy_uncompress(input, input_length, output, &output_length)
+ * == SNAPPY_OK) {
+ * ... Process(output, output_length) ...
+ * }
+ * free(output);
+ */
+snappy_status snappy_uncompress(const char* compressed,
+ size_t compressed_length,
+ char* uncompressed,
+ size_t* uncompressed_length);
+
+/*
+ * Returns the maximal size of the compressed representation of
+ * input data that is "source_length" bytes in length.
+ */
+size_t snappy_max_compressed_length(size_t source_length);
+
+/*
+ * REQUIRES: "compressed[]" was produced by snappy_compress()
+ * Returns SNAPPY_OK and stores the length of the uncompressed data in
+ * *result normally. Returns SNAPPY_INVALID_INPUT on parsing error.
+ * This operation takes O(1) time.
+ */
+snappy_status snappy_uncompressed_length(const char* compressed,
+ size_t compressed_length,
+ size_t* result);
+
+/*
+ * Check if the contents of "compressed[]" can be uncompressed successfully.
+ * Does not return the uncompressed data; if so, returns SNAPPY_OK,
+ * or if not, returns SNAPPY_INVALID_INPUT.
+ * Takes time proportional to compressed_length, but is usually at least a
+ * factor of four faster than actual decompression.
+ */
+snappy_status snappy_validate_compressed_buffer(const char* compressed,
+ size_t compressed_length);
+
+#ifdef __cplusplus
+} // extern "C"
+#endif
+
+#endif /* UTIL_SNAPPY_OPENSOURCE_SNAPPY_C_H_ */
diff --git a/app/snappy/snappy-internal.h b/app/snappy/snappy-internal.h
new file mode 100644
index 00000000..c99d3313
--- /dev/null
+++ b/app/snappy/snappy-internal.h
@@ -0,0 +1,150 @@
+// Copyright 2008 Google Inc. All Rights Reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+// Internals shared between the Snappy implementation and its unittest.
+
+#ifndef UTIL_SNAPPY_SNAPPY_INTERNAL_H_
+#define UTIL_SNAPPY_SNAPPY_INTERNAL_H_
+
+#include "snappy-stubs-internal.h"
+
+namespace snappy {
+namespace internal {
+
+class WorkingMemory {
+ public:
+ WorkingMemory() : large_table_(NULL) { }
+ ~WorkingMemory() { delete[] large_table_; }
+
+ // Allocates and clears a hash table using memory in "*this",
+ // stores the number of buckets in "*table_size" and returns a pointer to
+ // the base of the hash table.
+ uint16* GetHashTable(size_t input_size, int* table_size);
+
+ private:
+ uint16 small_table_[1<<10]; // 2KB
+ uint16* large_table_; // Allocated only when needed
+
+ DISALLOW_COPY_AND_ASSIGN(WorkingMemory);
+};
+
+// Flat array compression that does not emit the "uncompressed length"
+// prefix. Compresses "input" string to the "*op" buffer.
+//
+// REQUIRES: "input_length <= kBlockSize"
+// REQUIRES: "op" points to an array of memory that is at least
+// "MaxCompressedLength(input_length)" in size.
+// REQUIRES: All elements in "table[0..table_size-1]" are initialized to zero.
+// REQUIRES: "table_size" is a power of two
+//
+// Returns an "end" pointer into "op" buffer.
+// "end - op" is the compressed size of "input".
+char* CompressFragment(const char* input,
+ size_t input_length,
+ char* op,
+ uint16* table,
+ const int table_size);
+
+// Return the largest n such that
+//
+// s1[0,n-1] == s2[0,n-1]
+// and n <= (s2_limit - s2).
+//
+// Does not read *s2_limit or beyond.
+// Does not read *(s1 + (s2_limit - s2)) or beyond.
+// Requires that s2_limit >= s2.
+//
+// Separate implementation for x86_64, for speed. Uses the fact that
+// x86_64 is little endian.
+#if defined(ARCH_K8)
+static inline int FindMatchLength(const char* s1,
+ const char* s2,
+ const char* s2_limit) {
+ assert(s2_limit >= s2);
+ int matched = 0;
+
+ // Find out how long the match is. We loop over the data 64 bits at a
+ // time until we find a 64-bit block that doesn't match; then we find
+ // the first non-matching bit and use that to calculate the total
+ // length of the match.
+ while (PREDICT_TRUE(s2 <= s2_limit - 8)) {
+ if (PREDICT_FALSE(UNALIGNED_LOAD64(s2) == UNALIGNED_LOAD64(s1 + matched))) {
+ s2 += 8;
+ matched += 8;
+ } else {
+ // On current (mid-2008) Opteron models there is a 3% more
+ // efficient code sequence to find the first non-matching byte.
+ // However, what follows is ~10% better on Intel Core 2 and newer,
+ // and we expect AMD's bsf instruction to improve.
+ uint64 x = UNALIGNED_LOAD64(s2) ^ UNALIGNED_LOAD64(s1 + matched);
+ int matching_bits = Bits::FindLSBSetNonZero64(x);
+ matched += matching_bits >> 3;
+ return matched;
+ }
+ }
+ while (PREDICT_TRUE(s2 < s2_limit)) {
+ if (PREDICT_TRUE(s1[matched] == *s2)) {
+ ++s2;
+ ++matched;
+ } else {
+ return matched;
+ }
+ }
+ return matched;
+}
+#else
+static inline int FindMatchLength(const char* s1,
+ const char* s2,
+ const char* s2_limit) {
+ // Implementation based on the x86-64 version, above.
+ assert(s2_limit >= s2);
+ int matched = 0;
+
+ while (s2 <= s2_limit - 4 &&
+ UNALIGNED_LOAD32(s2) == UNALIGNED_LOAD32(s1 + matched)) {
+ s2 += 4;
+ matched += 4;
+ }
+ if (LittleEndian::IsLittleEndian() && s2 <= s2_limit - 4) {
+ uint32 x = UNALIGNED_LOAD32(s2) ^ UNALIGNED_LOAD32(s1 + matched);
+ int matching_bits = Bits::FindLSBSetNonZero(x);
+ matched += matching_bits >> 3;
+ } else {
+ while ((s2 < s2_limit) && (s1[matched] == *s2)) {
+ ++s2;
+ ++matched;
+ }
+ }
+ return matched;
+}
+#endif
+
+} // end namespace internal
+} // end namespace snappy
+
+#endif // UTIL_SNAPPY_SNAPPY_INTERNAL_H_
diff --git a/app/snappy/snappy-sinksource.cc b/app/snappy/snappy-sinksource.cc
new file mode 100644
index 00000000..5844552c
--- /dev/null
+++ b/app/snappy/snappy-sinksource.cc
@@ -0,0 +1,71 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include <string.h>
+
+#include "snappy-sinksource.h"
+
+namespace snappy {
+
+Source::~Source() { }
+
+Sink::~Sink() { }
+
+char* Sink::GetAppendBuffer(size_t length, char* scratch) {
+ return scratch;
+}
+
+ByteArraySource::~ByteArraySource() { }
+
+size_t ByteArraySource::Available() const { return left_; }
+
+const char* ByteArraySource::Peek(size_t* len) {
+ *len = left_;
+ return ptr_;
+}
+
+void ByteArraySource::Skip(size_t n) {
+ left_ -= n;
+ ptr_ += n;
+}
+
+UncheckedByteArraySink::~UncheckedByteArraySink() { }
+
+void UncheckedByteArraySink::Append(const char* data, size_t n) {
+ // Do no copying if the caller filled in the result of GetAppendBuffer()
+ if (data != dest_) {
+ memcpy(dest_, data, n);
+ }
+ dest_ += n;
+}
+
+char* UncheckedByteArraySink::GetAppendBuffer(size_t len, char* scratch) {
+ return dest_;
+}
+
+}
diff --git a/app/snappy/snappy-sinksource.h b/app/snappy/snappy-sinksource.h
new file mode 100644
index 00000000..faabfa1e
--- /dev/null
+++ b/app/snappy/snappy-sinksource.h
@@ -0,0 +1,137 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#ifndef UTIL_SNAPPY_SNAPPY_SINKSOURCE_H_
+#define UTIL_SNAPPY_SNAPPY_SINKSOURCE_H_
+
+#include <stddef.h>
+
+
+namespace snappy {
+
+// A Sink is an interface that consumes a sequence of bytes.
+class Sink {
+ public:
+ Sink() { }
+ virtual ~Sink();
+
+ // Append "bytes[0,n-1]" to this.
+ virtual void Append(const char* bytes, size_t n) = 0;
+
+ // Returns a writable buffer of the specified length for appending.
+ // May return a pointer to the caller-owned scratch buffer which
+ // must have at least the indicated length. The returned buffer is
+ // only valid until the next operation on this Sink.
+ //
+ // After writing at most "length" bytes, call Append() with the
+ // pointer returned from this function and the number of bytes
+ // written. Many Append() implementations will avoid copying
+ // bytes if this function returned an internal buffer.
+ //
+ // If a non-scratch buffer is returned, the caller may only pass a
+ // prefix of it to Append(). That is, it is not correct to pass an
+ // interior pointer of the returned array to Append().
+ //
+ // The default implementation always returns the scratch buffer.
+ virtual char* GetAppendBuffer(size_t length, char* scratch);
+
+
+ private:
+ // No copying
+ Sink(const Sink&);
+ void operator=(const Sink&);
+};
+
+// A Source is an interface that yields a sequence of bytes
+class Source {
+ public:
+ Source() { }
+ virtual ~Source();
+
+ // Return the number of bytes left to read from the source
+ virtual size_t Available() const = 0;
+
+ // Peek at the next flat region of the source. Does not reposition
+ // the source. The returned region is empty iff Available()==0.
+ //
+ // Returns a pointer to the beginning of the region and store its
+ // length in *len.
+ //
+ // The returned region is valid until the next call to Skip() or
+ // until this object is destroyed, whichever occurs first.
+ //
+ // The returned region may be larger than Available() (for example
+ // if this ByteSource is a view on a substring of a larger source).
+ // The caller is responsible for ensuring that it only reads the
+ // Available() bytes.
+ virtual const char* Peek(size_t* len) = 0;
+
+ // Skip the next n bytes. Invalidates any buffer returned by
+ // a previous call to Peek().
+ // REQUIRES: Available() >= n
+ virtual void Skip(size_t n) = 0;
+
+ private:
+ // No copying
+ Source(const Source&);
+ void operator=(const Source&);
+};
+
+// A Source implementation that yields the contents of a flat array
+class ByteArraySource : public Source {
+ public:
+ ByteArraySource(const char* p, size_t n) : ptr_(p), left_(n) { }
+ virtual ~ByteArraySource();
+ virtual size_t Available() const;
+ virtual const char* Peek(size_t* len);
+ virtual void Skip(size_t n);
+ private:
+ const char* ptr_;
+ size_t left_;
+};
+
+// A Sink implementation that writes to a flat array without any bound checks.
+class UncheckedByteArraySink : public Sink {
+ public:
+ explicit UncheckedByteArraySink(char* dest) : dest_(dest) { }
+ virtual ~UncheckedByteArraySink();
+ virtual void Append(const char* data, size_t n);
+ virtual char* GetAppendBuffer(size_t len, char* scratch);
+
+ // Return the current output pointer so that a caller can see how
+ // many bytes were produced.
+ // Note: this is not a Sink method.
+ char* CurrentDestination() const { return dest_; }
+ private:
+ char* dest_;
+};
+
+
+}
+
+#endif // UTIL_SNAPPY_SNAPPY_SINKSOURCE_H_
diff --git a/app/snappy/snappy-stubs-internal.cc b/app/snappy/snappy-stubs-internal.cc
new file mode 100644
index 00000000..6ed33437
--- /dev/null
+++ b/app/snappy/snappy-stubs-internal.cc
@@ -0,0 +1,42 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include <algorithm>
+#include <string>
+
+#include "snappy-stubs-internal.h"
+
+namespace snappy {
+
+void Varint::Append32(string* s, uint32 value) {
+ char buf[Varint::kMax32];
+ const char* p = Varint::Encode32(buf, value);
+ s->append(buf, p - buf);
+}
+
+} // namespace snappy
diff --git a/app/snappy/snappy-stubs-internal.h b/app/snappy/snappy-stubs-internal.h
new file mode 100644
index 00000000..12393b62
--- /dev/null
+++ b/app/snappy/snappy-stubs-internal.h
@@ -0,0 +1,491 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+// Various stubs for the open-source version of Snappy.
+
+#ifndef UTIL_SNAPPY_OPENSOURCE_SNAPPY_STUBS_INTERNAL_H_
+#define UTIL_SNAPPY_OPENSOURCE_SNAPPY_STUBS_INTERNAL_H_
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <string>
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+#ifdef HAVE_SYS_MMAN_H
+#include <sys/mman.h>
+#endif
+
+#include "snappy-stubs-public.h"
+
+#if defined(__x86_64__)
+
+// Enable 64-bit optimized versions of some routines.
+#define ARCH_K8 1
+
+#endif
+
+// Needed by OS X, among others.
+#ifndef MAP_ANONYMOUS
+#define MAP_ANONYMOUS MAP_ANON
+#endif
+
+// Pull in std::min, std::ostream, and the likes. This is safe because this
+// header file is never used from any public header files.
+using namespace std;
+
+// The size of an array, if known at compile-time.
+// Will give unexpected results if used on a pointer.
+// We undefine it first, since some compilers already have a definition.
+#ifdef ARRAYSIZE
+#undef ARRAYSIZE
+#endif
+#define ARRAYSIZE(a) (sizeof(a) / sizeof(*(a)))
+
+// Static prediction hints.
+#ifdef HAVE_BUILTIN_EXPECT
+#define PREDICT_FALSE(x) (__builtin_expect(x, 0))
+#define PREDICT_TRUE(x) (__builtin_expect(!!(x), 1))
+#else
+#define PREDICT_FALSE(x) x
+#define PREDICT_TRUE(x) x
+#endif
+
+// This is only used for recomputing the tag byte table used during
+// decompression; for simplicity we just remove it from the open-source
+// version (anyone who wants to regenerate it can just do the call
+// themselves within main()).
+#define DEFINE_bool(flag_name, default_value, description) \
+ bool FLAGS_ ## flag_name = default_value
+#define DECLARE_bool(flag_name) \
+ extern bool FLAGS_ ## flag_name
+
+namespace snappy {
+
+static const uint32 kuint32max = static_cast<uint32>(0xFFFFFFFF);
+static const int64 kint64max = static_cast<int64>(0x7FFFFFFFFFFFFFFFLL);
+
+// Potentially unaligned loads and stores.
+
+// x86 and PowerPC can simply do these loads and stores native.
+
+#if defined(__i386__) || defined(__x86_64__) || defined(__powerpc__)
+
+#define UNALIGNED_LOAD16(_p) (*reinterpret_cast<const uint16 *>(_p))
+#define UNALIGNED_LOAD32(_p) (*reinterpret_cast<const uint32 *>(_p))
+#define UNALIGNED_LOAD64(_p) (*reinterpret_cast<const uint64 *>(_p))
+
+#define UNALIGNED_STORE16(_p, _val) (*reinterpret_cast<uint16 *>(_p) = (_val))
+#define UNALIGNED_STORE32(_p, _val) (*reinterpret_cast<uint32 *>(_p) = (_val))
+#define UNALIGNED_STORE64(_p, _val) (*reinterpret_cast<uint64 *>(_p) = (_val))
+
+// ARMv7 and newer support native unaligned accesses, but only of 16-bit
+// and 32-bit values (not 64-bit); older versions either raise a fatal signal,
+// do an unaligned read and rotate the words around a bit, or do the reads very
+// slowly (trip through kernel mode). There's no simple #define that says just
+// “ARMv7 or higher”, so we have to filter away all ARMv5 and ARMv6
+// sub-architectures.
+//
+// This is a mess, but there's not much we can do about it.
+
+#elif defined(__arm__) && \
+ !defined(__ARM_ARCH_4__) && \
+ !defined(__ARM_ARCH_4T__) && \
+ !defined(__ARM_ARCH_5__) && \
+ !defined(__ARM_ARCH_5T__) && \
+ !defined(__ARM_ARCH_5TE__) && \
+ !defined(__ARM_ARCH_5TEJ__) && \
+ !defined(__ARM_ARCH_6__) && \
+ !defined(__ARM_ARCH_6J__) && \
+ !defined(__ARM_ARCH_6K__) && \
+ !defined(__ARM_ARCH_6Z__) && \
+ !defined(__ARM_ARCH_6ZK__) && \
+ !defined(__ARM_ARCH_6T2__)
+
+#define UNALIGNED_LOAD16(_p) (*reinterpret_cast<const uint16 *>(_p))
+#define UNALIGNED_LOAD32(_p) (*reinterpret_cast<const uint32 *>(_p))
+
+#define UNALIGNED_STORE16(_p, _val) (*reinterpret_cast<uint16 *>(_p) = (_val))
+#define UNALIGNED_STORE32(_p, _val) (*reinterpret_cast<uint32 *>(_p) = (_val))
+
+// TODO(user): NEON supports unaligned 64-bit loads and stores.
+// See if that would be more efficient on platforms supporting it,
+// at least for copies.
+
+inline uint64 UNALIGNED_LOAD64(const void *p) {
+ uint64 t;
+ memcpy(&t, p, sizeof t);
+ return t;
+}
+
+inline void UNALIGNED_STORE64(void *p, uint64 v) {
+ memcpy(p, &v, sizeof v);
+}
+
+#else
+
+// These functions are provided for architectures that don't support
+// unaligned loads and stores.
+
+inline uint16 UNALIGNED_LOAD16(const void *p) {
+ uint16 t;
+ memcpy(&t, p, sizeof t);
+ return t;
+}
+
+inline uint32 UNALIGNED_LOAD32(const void *p) {
+ uint32 t;
+ memcpy(&t, p, sizeof t);
+ return t;
+}
+
+inline uint64 UNALIGNED_LOAD64(const void *p) {
+ uint64 t;
+ memcpy(&t, p, sizeof t);
+ return t;
+}
+
+inline void UNALIGNED_STORE16(void *p, uint16 v) {
+ memcpy(p, &v, sizeof v);
+}
+
+inline void UNALIGNED_STORE32(void *p, uint32 v) {
+ memcpy(p, &v, sizeof v);
+}
+
+inline void UNALIGNED_STORE64(void *p, uint64 v) {
+ memcpy(p, &v, sizeof v);
+}
+
+#endif
+
+// This can be more efficient than UNALIGNED_LOAD64 + UNALIGNED_STORE64
+// on some platforms, in particular ARM.
+inline void UnalignedCopy64(const void *src, void *dst) {
+ if (sizeof(void *) == 8) {
+ UNALIGNED_STORE64(dst, UNALIGNED_LOAD64(src));
+ } else {
+ const char *src_char = reinterpret_cast<const char *>(src);
+ char *dst_char = reinterpret_cast<char *>(dst);
+
+ UNALIGNED_STORE32(dst_char, UNALIGNED_LOAD32(src_char));
+ UNALIGNED_STORE32(dst_char + 4, UNALIGNED_LOAD32(src_char + 4));
+ }
+}
+
+// The following guarantees declaration of the byte swap functions.
+#ifdef WORDS_BIGENDIAN
+
+#ifdef HAVE_SYS_BYTEORDER_H
+#include <sys/byteorder.h>
+#endif
+
+#ifdef HAVE_SYS_ENDIAN_H
+#include <sys/endian.h>
+#endif
+
+#ifdef _MSC_VER
+#include <stdlib.h>
+#define bswap_16(x) _byteswap_ushort(x)
+#define bswap_32(x) _byteswap_ulong(x)
+#define bswap_64(x) _byteswap_uint64(x)
+
+#elif defined(__APPLE__)
+// Mac OS X / Darwin features
+#include <libkern/OSByteOrder.h>
+#define bswap_16(x) OSSwapInt16(x)
+#define bswap_32(x) OSSwapInt32(x)
+#define bswap_64(x) OSSwapInt64(x)
+
+#elif defined(HAVE_BYTESWAP_H)
+#include <byteswap.h>
+
+#elif defined(bswap32)
+// FreeBSD defines bswap{16,32,64} in <sys/endian.h> (already #included).
+#define bswap_16(x) bswap16(x)
+#define bswap_32(x) bswap32(x)
+#define bswap_64(x) bswap64(x)
+
+#elif defined(BSWAP_64)
+// Solaris 10 defines BSWAP_{16,32,64} in <sys/byteorder.h> (already #included).
+#define bswap_16(x) BSWAP_16(x)
+#define bswap_32(x) BSWAP_32(x)
+#define bswap_64(x) BSWAP_64(x)
+
+#else
+
+inline uint16 bswap_16(uint16 x) {
+ return (x << 8) | (x >> 8);
+}
+
+inline uint32 bswap_32(uint32 x) {
+ x = ((x & 0xff00ff00UL) >> 8) | ((x & 0x00ff00ffUL) << 8);
+ return (x >> 16) | (x << 16);
+}
+
+inline uint64 bswap_64(uint64 x) {
+ x = ((x & 0xff00ff00ff00ff00ULL) >> 8) | ((x & 0x00ff00ff00ff00ffULL) << 8);
+ x = ((x & 0xffff0000ffff0000ULL) >> 16) | ((x & 0x0000ffff0000ffffULL) << 16);
+ return (x >> 32) | (x << 32);
+}
+
+#endif
+
+#endif // WORDS_BIGENDIAN
+
+// Convert to little-endian storage, opposite of network format.
+// Convert x from host to little endian: x = LittleEndian.FromHost(x);
+// convert x from little endian to host: x = LittleEndian.ToHost(x);
+//
+// Store values into unaligned memory converting to little endian order:
+// LittleEndian.Store16(p, x);
+//
+// Load unaligned values stored in little endian converting to host order:
+// x = LittleEndian.Load16(p);
+class LittleEndian {
+ public:
+ // Conversion functions.
+#ifdef WORDS_BIGENDIAN
+
+ static uint16 FromHost16(uint16 x) { return bswap_16(x); }
+ static uint16 ToHost16(uint16 x) { return bswap_16(x); }
+
+ static uint32 FromHost32(uint32 x) { return bswap_32(x); }
+ static uint32 ToHost32(uint32 x) { return bswap_32(x); }
+
+ static bool IsLittleEndian() { return false; }
+
+#else // !defined(WORDS_BIGENDIAN)
+
+ static uint16 FromHost16(uint16 x) { return x; }
+ static uint16 ToHost16(uint16 x) { return x; }
+
+ static uint32 FromHost32(uint32 x) { return x; }
+ static uint32 ToHost32(uint32 x) { return x; }
+
+ static bool IsLittleEndian() { return true; }
+
+#endif // !defined(WORDS_BIGENDIAN)
+
+ // Functions to do unaligned loads and stores in little-endian order.
+ static uint16 Load16(const void *p) {
+ return ToHost16(UNALIGNED_LOAD16(p));
+ }
+
+ static void Store16(void *p, uint16 v) {
+ UNALIGNED_STORE16(p, FromHost16(v));
+ }
+
+ static uint32 Load32(const void *p) {
+ return ToHost32(UNALIGNED_LOAD32(p));
+ }
+
+ static void Store32(void *p, uint32 v) {
+ UNALIGNED_STORE32(p, FromHost32(v));
+ }
+};
+
+// Some bit-manipulation functions.
+class Bits {
+ public:
+ // Return floor(log2(n)) for positive integer n. Returns -1 iff n == 0.
+ static int Log2Floor(uint32 n);
+
+ // Return the first set least / most significant bit, 0-indexed. Returns an
+ // undefined value if n == 0. FindLSBSetNonZero() is similar to ffs() except
+ // that it's 0-indexed.
+ static int FindLSBSetNonZero(uint32 n);
+ static int FindLSBSetNonZero64(uint64 n);
+
+ private:
+ DISALLOW_COPY_AND_ASSIGN(Bits);
+};
+
+#ifdef HAVE_BUILTIN_CTZ
+
+inline int Bits::Log2Floor(uint32 n) {
+ return n == 0 ? -1 : 31 ^ __builtin_clz(n);
+}
+
+inline int Bits::FindLSBSetNonZero(uint32 n) {
+ return __builtin_ctz(n);
+}
+
+inline int Bits::FindLSBSetNonZero64(uint64 n) {
+ return __builtin_ctzll(n);
+}
+
+#else // Portable versions.
+
+inline int Bits::Log2Floor(uint32 n) {
+ if (n == 0)
+ return -1;
+ int log = 0;
+ uint32 value = n;
+ for (int i = 4; i >= 0; --i) {
+ int shift = (1 << i);
+ uint32 x = value >> shift;
+ if (x != 0) {
+ value = x;
+ log += shift;
+ }
+ }
+ assert(value == 1);
+ return log;
+}
+
+inline int Bits::FindLSBSetNonZero(uint32 n) {
+ int rc = 31;
+ for (int i = 4, shift = 1 << 4; i >= 0; --i) {
+ const uint32 x = n << shift;
+ if (x != 0) {
+ n = x;
+ rc -= shift;
+ }
+ shift >>= 1;
+ }
+ return rc;
+}
+
+// FindLSBSetNonZero64() is defined in terms of FindLSBSetNonZero().
+inline int Bits::FindLSBSetNonZero64(uint64 n) {
+ const uint32 bottombits = static_cast<uint32>(n);
+ if (bottombits == 0) {
+ // Bottom bits are zero, so scan in top bits
+ return 32 + FindLSBSetNonZero(static_cast<uint32>(n >> 32));
+ } else {
+ return FindLSBSetNonZero(bottombits);
+ }
+}
+
+#endif // End portable versions.
+
+// Variable-length integer encoding.
+class Varint {
+ public:
+ // Maximum lengths of varint encoding of uint32.
+ static const int kMax32 = 5;
+
+ // Attempts to parse a varint32 from a prefix of the bytes in [ptr,limit-1].
+ // Never reads a character at or beyond limit. If a valid/terminated varint32
+ // was found in the range, stores it in *OUTPUT and returns a pointer just
+ // past the last byte of the varint32. Else returns NULL. On success,
+ // "result <= limit".
+ static const char* Parse32WithLimit(const char* ptr, const char* limit,
+ uint32* OUTPUT);
+
+ // REQUIRES "ptr" points to a buffer of length sufficient to hold "v".
+ // EFFECTS Encodes "v" into "ptr" and returns a pointer to the
+ // byte just past the last encoded byte.
+ static char* Encode32(char* ptr, uint32 v);
+
+ // EFFECTS Appends the varint representation of "value" to "*s".
+ static void Append32(string* s, uint32 value);
+};
+
+inline const char* Varint::Parse32WithLimit(const char* p,
+ const char* l,
+ uint32* OUTPUT) {
+ const unsigned char* ptr = reinterpret_cast<const unsigned char*>(p);
+ const unsigned char* limit = reinterpret_cast<const unsigned char*>(l);
+ uint32 b, result;
+ if (ptr >= limit) return NULL;
+ b = *(ptr++); result = b & 127; if (b < 128) goto done;
+ if (ptr >= limit) return NULL;
+ b = *(ptr++); result |= (b & 127) << 7; if (b < 128) goto done;
+ if (ptr >= limit) return NULL;
+ b = *(ptr++); result |= (b & 127) << 14; if (b < 128) goto done;
+ if (ptr >= limit) return NULL;
+ b = *(ptr++); result |= (b & 127) << 21; if (b < 128) goto done;
+ if (ptr >= limit) return NULL;
+ b = *(ptr++); result |= (b & 127) << 28; if (b < 16) goto done;
+ return NULL; // Value is too long to be a varint32
+ done:
+ *OUTPUT = result;
+ return reinterpret_cast<const char*>(ptr);
+}
+
+inline char* Varint::Encode32(char* sptr, uint32 v) {
+ // Operate on characters as unsigneds
+ unsigned char* ptr = reinterpret_cast<unsigned char*>(sptr);
+ static const int B = 128;
+ if (v < (1<<7)) {
+ *(ptr++) = v;
+ } else if (v < (1<<14)) {
+ *(ptr++) = v | B;
+ *(ptr++) = v>>7;
+ } else if (v < (1<<21)) {
+ *(ptr++) = v | B;
+ *(ptr++) = (v>>7) | B;
+ *(ptr++) = v>>14;
+ } else if (v < (1<<28)) {
+ *(ptr++) = v | B;
+ *(ptr++) = (v>>7) | B;
+ *(ptr++) = (v>>14) | B;
+ *(ptr++) = v>>21;
+ } else {
+ *(ptr++) = v | B;
+ *(ptr++) = (v>>7) | B;
+ *(ptr++) = (v>>14) | B;
+ *(ptr++) = (v>>21) | B;
+ *(ptr++) = v>>28;
+ }
+ return reinterpret_cast<char*>(ptr);
+}
+
+// If you know the internal layout of the std::string in use, you can
+// replace this function with one that resizes the string without
+// filling the new space with zeros (if applicable) --
+// it will be non-portable but faster.
+inline void STLStringResizeUninitialized(string* s, size_t new_size) {
+ s->resize(new_size);
+}
+
+// Return a mutable char* pointing to a string's internal buffer,
+// which may not be null-terminated. Writing through this pointer will
+// modify the string.
+//
+// string_as_array(&str)[i] is valid for 0 <= i < str.size() until the
+// next call to a string method that invalidates iterators.
+//
+// As of 2006-04, there is no standard-blessed way of getting a
+// mutable reference to a string's internal buffer. However, issue 530
+// (http://www.open-std.org/JTC1/SC22/WG21/docs/lwg-defects.html#530)
+// proposes this as the method. It will officially be part of the standard
+// for C++0x. This should already work on all current implementations.
+inline char* string_as_array(string* str) {
+ return str->empty() ? NULL : &*str->begin();
+}
+
+} // namespace snappy
+
+#endif // UTIL_SNAPPY_OPENSOURCE_SNAPPY_STUBS_INTERNAL_H_
diff --git a/app/snappy/snappy-stubs-public.h b/app/snappy/snappy-stubs-public.h
new file mode 100644
index 00000000..96d88650
--- /dev/null
+++ b/app/snappy/snappy-stubs-public.h
@@ -0,0 +1,85 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+// Author: sesse@google.com (Steinar H. Gunderson)
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+// Various type stubs for the open-source version of Snappy.
+//
+// This file cannot include config.h, as it is included from snappy.h,
+// which is a public header. Instead, snappy-stubs-public.h is generated by
+// from snappy-stubs-public.h.in at configure time.
+
+#ifndef UTIL_SNAPPY_OPENSOURCE_SNAPPY_STUBS_PUBLIC_H_
+#define UTIL_SNAPPY_OPENSOURCE_SNAPPY_STUBS_PUBLIC_H_
+
+#if 1
+#include <stdint.h>
+#endif
+
+#if 1
+#include <stddef.h>
+#endif
+
+#define SNAPPY_MAJOR 1
+#define SNAPPY_MINOR 1
+#define SNAPPY_PATCHLEVEL 0
+#define SNAPPY_VERSION \
+ ((SNAPPY_MAJOR << 16) | (SNAPPY_MINOR << 8) | SNAPPY_PATCHLEVEL)
+
+#include <string>
+
+namespace snappy {
+
+#if 1
+typedef int8_t int8;
+typedef uint8_t uint8;
+typedef int16_t int16;
+typedef uint16_t uint16;
+typedef int32_t int32;
+typedef uint32_t uint32;
+typedef int64_t int64;
+typedef uint64_t uint64;
+#else
+typedef signed char int8;
+typedef unsigned char uint8;
+typedef short int16;
+typedef unsigned short uint16;
+typedef int int32;
+typedef unsigned int uint32;
+typedef long long int64;
+typedef unsigned long long uint64;
+#endif
+
+typedef std::string string;
+
+#define DISALLOW_COPY_AND_ASSIGN(TypeName) \
+ TypeName(const TypeName&); \
+ void operator=(const TypeName&)
+
+} // namespace snappy
+
+#endif // UTIL_SNAPPY_OPENSOURCE_SNAPPY_STUBS_PUBLIC_H_
diff --git a/app/snappy/snappy-stubs-public.h.in b/app/snappy/snappy-stubs-public.h.in
new file mode 100644
index 00000000..f0babcbe
--- /dev/null
+++ b/app/snappy/snappy-stubs-public.h.in
@@ -0,0 +1,85 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+// Author: sesse@google.com (Steinar H. Gunderson)
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+// Various type stubs for the open-source version of Snappy.
+//
+// This file cannot include config.h, as it is included from snappy.h,
+// which is a public header. Instead, snappy-stubs-public.h is generated by
+// from snappy-stubs-public.h.in at configure time.
+
+#ifndef UTIL_SNAPPY_OPENSOURCE_SNAPPY_STUBS_PUBLIC_H_
+#define UTIL_SNAPPY_OPENSOURCE_SNAPPY_STUBS_PUBLIC_H_
+
+#if @ac_cv_have_stdint_h@
+#include <stdint.h>
+#endif
+
+#if @ac_cv_have_stddef_h@
+#include <stddef.h>
+#endif
+
+#define SNAPPY_MAJOR @SNAPPY_MAJOR@
+#define SNAPPY_MINOR @SNAPPY_MINOR@
+#define SNAPPY_PATCHLEVEL @SNAPPY_PATCHLEVEL@
+#define SNAPPY_VERSION \
+ ((SNAPPY_MAJOR << 16) | (SNAPPY_MINOR << 8) | SNAPPY_PATCHLEVEL)
+
+#include <string>
+
+namespace snappy {
+
+#if @ac_cv_have_stdint_h@
+typedef int8_t int8;
+typedef uint8_t uint8;
+typedef int16_t int16;
+typedef uint16_t uint16;
+typedef int32_t int32;
+typedef uint32_t uint32;
+typedef int64_t int64;
+typedef uint64_t uint64;
+#else
+typedef signed char int8;
+typedef unsigned char uint8;
+typedef short int16;
+typedef unsigned short uint16;
+typedef int int32;
+typedef unsigned int uint32;
+typedef long long int64;
+typedef unsigned long long uint64;
+#endif
+
+typedef std::string string;
+
+#define DISALLOW_COPY_AND_ASSIGN(TypeName) \
+ TypeName(const TypeName&); \
+ void operator=(const TypeName&)
+
+} // namespace snappy
+
+#endif // UTIL_SNAPPY_OPENSOURCE_SNAPPY_STUBS_PUBLIC_H_
diff --git a/app/snappy/snappy-test.cc b/app/snappy/snappy-test.cc
new file mode 100644
index 00000000..46194109
--- /dev/null
+++ b/app/snappy/snappy-test.cc
@@ -0,0 +1,606 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+// Various stubs for the unit tests for the open-source version of Snappy.
+
+#include "snappy-test.h"
+
+#ifdef HAVE_WINDOWS_H
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#endif
+
+#include <algorithm>
+
+DEFINE_bool(run_microbenchmarks, true,
+ "Run microbenchmarks before doing anything else.");
+
+namespace snappy {
+
+string ReadTestDataFile(const string& base, size_t size_limit) {
+ string contents;
+ const char* srcdir = getenv("srcdir"); // This is set by Automake.
+ string prefix;
+ if (srcdir) {
+ prefix = string(srcdir) + "/";
+ }
+ file::GetContents(prefix + "testdata/" + base, &contents, file::Defaults()
+ ).CheckSuccess();
+ if (size_limit > 0) {
+ contents = contents.substr(0, size_limit);
+ }
+ return contents;
+}
+
+string ReadTestDataFile(const string& base) {
+ return ReadTestDataFile(base, 0);
+}
+
+string StringPrintf(const char* format, ...) {
+ char buf[4096];
+ va_list ap;
+ va_start(ap, format);
+ vsnprintf(buf, sizeof(buf), format, ap);
+ va_end(ap);
+ return buf;
+}
+
+bool benchmark_running = false;
+int64 benchmark_real_time_us = 0;
+int64 benchmark_cpu_time_us = 0;
+string *benchmark_label = NULL;
+int64 benchmark_bytes_processed = 0;
+
+void ResetBenchmarkTiming() {
+ benchmark_real_time_us = 0;
+ benchmark_cpu_time_us = 0;
+}
+
+#ifdef WIN32
+LARGE_INTEGER benchmark_start_real;
+FILETIME benchmark_start_cpu;
+#else // WIN32
+struct timeval benchmark_start_real;
+struct rusage benchmark_start_cpu;
+#endif // WIN32
+
+void StartBenchmarkTiming() {
+#ifdef WIN32
+ QueryPerformanceCounter(&benchmark_start_real);
+ FILETIME dummy;
+ CHECK(GetProcessTimes(
+ GetCurrentProcess(), &dummy, &dummy, &dummy, &benchmark_start_cpu));
+#else
+ gettimeofday(&benchmark_start_real, NULL);
+ if (getrusage(RUSAGE_SELF, &benchmark_start_cpu) == -1) {
+ perror("getrusage(RUSAGE_SELF)");
+ exit(1);
+ }
+#endif
+ benchmark_running = true;
+}
+
+void StopBenchmarkTiming() {
+ if (!benchmark_running) {
+ return;
+ }
+
+#ifdef WIN32
+ LARGE_INTEGER benchmark_stop_real;
+ LARGE_INTEGER benchmark_frequency;
+ QueryPerformanceCounter(&benchmark_stop_real);
+ QueryPerformanceFrequency(&benchmark_frequency);
+
+ double elapsed_real = static_cast<double>(
+ benchmark_stop_real.QuadPart - benchmark_start_real.QuadPart) /
+ benchmark_frequency.QuadPart;
+ benchmark_real_time_us += elapsed_real * 1e6 + 0.5;
+
+ FILETIME benchmark_stop_cpu, dummy;
+ CHECK(GetProcessTimes(
+ GetCurrentProcess(), &dummy, &dummy, &dummy, &benchmark_stop_cpu));
+
+ ULARGE_INTEGER start_ulargeint;
+ start_ulargeint.LowPart = benchmark_start_cpu.dwLowDateTime;
+ start_ulargeint.HighPart = benchmark_start_cpu.dwHighDateTime;
+
+ ULARGE_INTEGER stop_ulargeint;
+ stop_ulargeint.LowPart = benchmark_stop_cpu.dwLowDateTime;
+ stop_ulargeint.HighPart = benchmark_stop_cpu.dwHighDateTime;
+
+ benchmark_cpu_time_us +=
+ (stop_ulargeint.QuadPart - start_ulargeint.QuadPart + 5) / 10;
+#else // WIN32
+ struct timeval benchmark_stop_real;
+ gettimeofday(&benchmark_stop_real, NULL);
+ benchmark_real_time_us +=
+ 1000000 * (benchmark_stop_real.tv_sec - benchmark_start_real.tv_sec);
+ benchmark_real_time_us +=
+ (benchmark_stop_real.tv_usec - benchmark_start_real.tv_usec);
+
+ struct rusage benchmark_stop_cpu;
+ if (getrusage(RUSAGE_SELF, &benchmark_stop_cpu) == -1) {
+ perror("getrusage(RUSAGE_SELF)");
+ exit(1);
+ }
+ benchmark_cpu_time_us += 1000000 * (benchmark_stop_cpu.ru_utime.tv_sec -
+ benchmark_start_cpu.ru_utime.tv_sec);
+ benchmark_cpu_time_us += (benchmark_stop_cpu.ru_utime.tv_usec -
+ benchmark_start_cpu.ru_utime.tv_usec);
+#endif // WIN32
+
+ benchmark_running = false;
+}
+
+void SetBenchmarkLabel(const string& str) {
+ if (benchmark_label) {
+ delete benchmark_label;
+ }
+ benchmark_label = new string(str);
+}
+
+void SetBenchmarkBytesProcessed(int64 bytes) {
+ benchmark_bytes_processed = bytes;
+}
+
+struct BenchmarkRun {
+ int64 real_time_us;
+ int64 cpu_time_us;
+};
+
+struct BenchmarkCompareCPUTime {
+ bool operator() (const BenchmarkRun& a, const BenchmarkRun& b) const {
+ return a.cpu_time_us < b.cpu_time_us;
+ }
+};
+
+void Benchmark::Run() {
+ for (int test_case_num = start_; test_case_num <= stop_; ++test_case_num) {
+ // Run a few iterations first to find out approximately how fast
+ // the benchmark is.
+ const int kCalibrateIterations = 100;
+ ResetBenchmarkTiming();
+ StartBenchmarkTiming();
+ (*function_)(kCalibrateIterations, test_case_num);
+ StopBenchmarkTiming();
+
+ // Let each test case run for about 200ms, but at least as many
+ // as we used to calibrate.
+ // Run five times and pick the median.
+ const int kNumRuns = 5;
+ const int kMedianPos = kNumRuns / 2;
+ int num_iterations = 0;
+ if (benchmark_real_time_us > 0) {
+ num_iterations = 200000 * kCalibrateIterations / benchmark_real_time_us;
+ }
+ num_iterations = max(num_iterations, kCalibrateIterations);
+ BenchmarkRun benchmark_runs[kNumRuns];
+
+ for (int run = 0; run < kNumRuns; ++run) {
+ ResetBenchmarkTiming();
+ StartBenchmarkTiming();
+ (*function_)(num_iterations, test_case_num);
+ StopBenchmarkTiming();
+
+ benchmark_runs[run].real_time_us = benchmark_real_time_us;
+ benchmark_runs[run].cpu_time_us = benchmark_cpu_time_us;
+ }
+
+ string heading = StringPrintf("%s/%d", name_.c_str(), test_case_num);
+ string human_readable_speed;
+
+ nth_element(benchmark_runs,
+ benchmark_runs + kMedianPos,
+ benchmark_runs + kNumRuns,
+ BenchmarkCompareCPUTime());
+ int64 real_time_us = benchmark_runs[kMedianPos].real_time_us;
+ int64 cpu_time_us = benchmark_runs[kMedianPos].cpu_time_us;
+ if (cpu_time_us <= 0) {
+ human_readable_speed = "?";
+ } else {
+ int64 bytes_per_second =
+ benchmark_bytes_processed * 1000000 / cpu_time_us;
+ if (bytes_per_second < 1024) {
+ human_readable_speed = StringPrintf("%dB/s", bytes_per_second);
+ } else if (bytes_per_second < 1024 * 1024) {
+ human_readable_speed = StringPrintf(
+ "%.1fkB/s", bytes_per_second / 1024.0f);
+ } else if (bytes_per_second < 1024 * 1024 * 1024) {
+ human_readable_speed = StringPrintf(
+ "%.1fMB/s", bytes_per_second / (1024.0f * 1024.0f));
+ } else {
+ human_readable_speed = StringPrintf(
+ "%.1fGB/s", bytes_per_second / (1024.0f * 1024.0f * 1024.0f));
+ }
+ }
+
+ fprintf(stderr,
+#ifdef WIN32
+ "%-18s %10I64d %10I64d %10d %s %s\n",
+#else
+ "%-18s %10lld %10lld %10d %s %s\n",
+#endif
+ heading.c_str(),
+ static_cast<long long>(real_time_us * 1000 / num_iterations),
+ static_cast<long long>(cpu_time_us * 1000 / num_iterations),
+ num_iterations,
+ human_readable_speed.c_str(),
+ benchmark_label->c_str());
+ }
+}
+
+#ifdef HAVE_LIBZ
+
+ZLib::ZLib()
+ : comp_init_(false),
+ uncomp_init_(false) {
+ Reinit();
+}
+
+ZLib::~ZLib() {
+ if (comp_init_) { deflateEnd(&comp_stream_); }
+ if (uncomp_init_) { inflateEnd(&uncomp_stream_); }
+}
+
+void ZLib::Reinit() {
+ compression_level_ = Z_DEFAULT_COMPRESSION;
+ window_bits_ = MAX_WBITS;
+ mem_level_ = 8; // DEF_MEM_LEVEL
+ if (comp_init_) {
+ deflateEnd(&comp_stream_);
+ comp_init_ = false;
+ }
+ if (uncomp_init_) {
+ inflateEnd(&uncomp_stream_);
+ uncomp_init_ = false;
+ }
+ first_chunk_ = true;
+}
+
+void ZLib::Reset() {
+ first_chunk_ = true;
+}
+
+// --------- COMPRESS MODE
+
+// Initialization method to be called if we hit an error while
+// compressing. On hitting an error, call this method before returning
+// the error.
+void ZLib::CompressErrorInit() {
+ deflateEnd(&comp_stream_);
+ comp_init_ = false;
+ Reset();
+}
+
+int ZLib::DeflateInit() {
+ return deflateInit2(&comp_stream_,
+ compression_level_,
+ Z_DEFLATED,
+ window_bits_,
+ mem_level_,
+ Z_DEFAULT_STRATEGY);
+}
+
+int ZLib::CompressInit(Bytef *dest, uLongf *destLen,
+ const Bytef *source, uLong *sourceLen) {
+ int err;
+
+ comp_stream_.next_in = (Bytef*)source;
+ comp_stream_.avail_in = (uInt)*sourceLen;
+ if ((uLong)comp_stream_.avail_in != *sourceLen) return Z_BUF_ERROR;
+ comp_stream_.next_out = dest;
+ comp_stream_.avail_out = (uInt)*destLen;
+ if ((uLong)comp_stream_.avail_out != *destLen) return Z_BUF_ERROR;
+
+ if ( !first_chunk_ ) // only need to set up stream the first time through
+ return Z_OK;
+
+ if (comp_init_) { // we've already initted it
+ err = deflateReset(&comp_stream_);
+ if (err != Z_OK) {
+ LOG(WARNING) << "ERROR: Can't reset compress object; creating a new one";
+ deflateEnd(&comp_stream_);
+ comp_init_ = false;
+ }
+ }
+ if (!comp_init_) { // first use
+ comp_stream_.zalloc = (alloc_func)0;
+ comp_stream_.zfree = (free_func)0;
+ comp_stream_.opaque = (voidpf)0;
+ err = DeflateInit();
+ if (err != Z_OK) return err;
+ comp_init_ = true;
+ }
+ return Z_OK;
+}
+
+// In a perfect world we'd always have the full buffer to compress
+// when the time came, and we could just call Compress(). Alas, we
+// want to do chunked compression on our webserver. In this
+// application, we compress the header, send it off, then compress the
+// results, send them off, then compress the footer. Thus we need to
+// use the chunked compression features of zlib.
+int ZLib::CompressAtMostOrAll(Bytef *dest, uLongf *destLen,
+ const Bytef *source, uLong *sourceLen,
+ int flush_mode) { // Z_FULL_FLUSH or Z_FINISH
+ int err;
+
+ if ( (err=CompressInit(dest, destLen, source, sourceLen)) != Z_OK )
+ return err;
+
+ // This is used to figure out how many bytes we wrote *this chunk*
+ int compressed_size = comp_stream_.total_out;
+
+ // Some setup happens only for the first chunk we compress in a run
+ if ( first_chunk_ ) {
+ first_chunk_ = false;
+ }
+
+ // flush_mode is Z_FINISH for all mode, Z_SYNC_FLUSH for incremental
+ // compression.
+ err = deflate(&comp_stream_, flush_mode);
+
+ *sourceLen = comp_stream_.avail_in;
+
+ if ((err == Z_STREAM_END || err == Z_OK)
+ && comp_stream_.avail_in == 0
+ && comp_stream_.avail_out != 0 ) {
+ // we processed everything ok and the output buffer was large enough.
+ ;
+ } else if (err == Z_STREAM_END && comp_stream_.avail_in > 0) {
+ return Z_BUF_ERROR; // should never happen
+ } else if (err != Z_OK && err != Z_STREAM_END && err != Z_BUF_ERROR) {
+ // an error happened
+ CompressErrorInit();
+ return err;
+ } else if (comp_stream_.avail_out == 0) { // not enough space
+ err = Z_BUF_ERROR;
+ }
+
+ assert(err == Z_OK || err == Z_STREAM_END || err == Z_BUF_ERROR);
+ if (err == Z_STREAM_END)
+ err = Z_OK;
+
+ // update the crc and other metadata
+ compressed_size = comp_stream_.total_out - compressed_size; // delta
+ *destLen = compressed_size;
+
+ return err;
+}
+
+int ZLib::CompressChunkOrAll(Bytef *dest, uLongf *destLen,
+ const Bytef *source, uLong sourceLen,
+ int flush_mode) { // Z_FULL_FLUSH or Z_FINISH
+ const int ret =
+ CompressAtMostOrAll(dest, destLen, source, &sourceLen, flush_mode);
+ if (ret == Z_BUF_ERROR)
+ CompressErrorInit();
+ return ret;
+}
+
+// This routine only initializes the compression stream once. Thereafter, it
+// just does a deflateReset on the stream, which should be faster.
+int ZLib::Compress(Bytef *dest, uLongf *destLen,
+ const Bytef *source, uLong sourceLen) {
+ int err;
+ if ( (err=CompressChunkOrAll(dest, destLen, source, sourceLen,
+ Z_FINISH)) != Z_OK )
+ return err;
+ Reset(); // reset for next call to Compress
+
+ return Z_OK;
+}
+
+
+// --------- UNCOMPRESS MODE
+
+int ZLib::InflateInit() {
+ return inflateInit2(&uncomp_stream_, MAX_WBITS);
+}
+
+// Initialization method to be called if we hit an error while
+// uncompressing. On hitting an error, call this method before
+// returning the error.
+void ZLib::UncompressErrorInit() {
+ inflateEnd(&uncomp_stream_);
+ uncomp_init_ = false;
+ Reset();
+}
+
+int ZLib::UncompressInit(Bytef *dest, uLongf *destLen,
+ const Bytef *source, uLong *sourceLen) {
+ int err;
+
+ uncomp_stream_.next_in = (Bytef*)source;
+ uncomp_stream_.avail_in = (uInt)*sourceLen;
+ // Check for source > 64K on 16-bit machine:
+ if ((uLong)uncomp_stream_.avail_in != *sourceLen) return Z_BUF_ERROR;
+
+ uncomp_stream_.next_out = dest;
+ uncomp_stream_.avail_out = (uInt)*destLen;
+ if ((uLong)uncomp_stream_.avail_out != *destLen) return Z_BUF_ERROR;
+
+ if ( !first_chunk_ ) // only need to set up stream the first time through
+ return Z_OK;
+
+ if (uncomp_init_) { // we've already initted it
+ err = inflateReset(&uncomp_stream_);
+ if (err != Z_OK) {
+ LOG(WARNING)
+ << "ERROR: Can't reset uncompress object; creating a new one";
+ UncompressErrorInit();
+ }
+ }
+ if (!uncomp_init_) {
+ uncomp_stream_.zalloc = (alloc_func)0;
+ uncomp_stream_.zfree = (free_func)0;
+ uncomp_stream_.opaque = (voidpf)0;
+ err = InflateInit();
+ if (err != Z_OK) return err;
+ uncomp_init_ = true;
+ }
+ return Z_OK;
+}
+
+// If you compressed your data a chunk at a time, with CompressChunk,
+// you can uncompress it a chunk at a time with UncompressChunk.
+// Only difference bewteen chunked and unchunked uncompression
+// is the flush mode we use: Z_SYNC_FLUSH (chunked) or Z_FINISH (unchunked).
+int ZLib::UncompressAtMostOrAll(Bytef *dest, uLongf *destLen,
+ const Bytef *source, uLong *sourceLen,
+ int flush_mode) { // Z_SYNC_FLUSH or Z_FINISH
+ int err = Z_OK;
+
+ if ( (err=UncompressInit(dest, destLen, source, sourceLen)) != Z_OK ) {
+ LOG(WARNING) << "UncompressInit: Error: " << err << " SourceLen: "
+ << *sourceLen;
+ return err;
+ }
+
+ // This is used to figure out how many output bytes we wrote *this chunk*:
+ const uLong old_total_out = uncomp_stream_.total_out;
+
+ // This is used to figure out how many input bytes we read *this chunk*:
+ const uLong old_total_in = uncomp_stream_.total_in;
+
+ // Some setup happens only for the first chunk we compress in a run
+ if ( first_chunk_ ) {
+ first_chunk_ = false; // so we don't do this again
+
+ // For the first chunk *only* (to avoid infinite troubles), we let
+ // there be no actual data to uncompress. This sometimes triggers
+ // when the input is only the gzip header, say.
+ if ( *sourceLen == 0 ) {
+ *destLen = 0;
+ return Z_OK;
+ }
+ }
+
+ // We'll uncompress as much as we can. If we end OK great, otherwise
+ // if we get an error that seems to be the gzip footer, we store the
+ // gzip footer and return OK, otherwise we return the error.
+
+ // flush_mode is Z_SYNC_FLUSH for chunked mode, Z_FINISH for all mode.
+ err = inflate(&uncomp_stream_, flush_mode);
+
+ // Figure out how many bytes of the input zlib slurped up:
+ const uLong bytes_read = uncomp_stream_.total_in - old_total_in;
+ CHECK_LE(source + bytes_read, source + *sourceLen);
+ *sourceLen = uncomp_stream_.avail_in;
+
+ if ((err == Z_STREAM_END || err == Z_OK) // everything went ok
+ && uncomp_stream_.avail_in == 0) { // and we read it all
+ ;
+ } else if (err == Z_STREAM_END && uncomp_stream_.avail_in > 0) {
+ LOG(WARNING)
+ << "UncompressChunkOrAll: Received some extra data, bytes total: "
+ << uncomp_stream_.avail_in << " bytes: "
+ << string(reinterpret_cast<const char *>(uncomp_stream_.next_in),
+ min(int(uncomp_stream_.avail_in), 20));
+ UncompressErrorInit();
+ return Z_DATA_ERROR; // what's the extra data for?
+ } else if (err != Z_OK && err != Z_STREAM_END && err != Z_BUF_ERROR) {
+ // an error happened
+ LOG(WARNING) << "UncompressChunkOrAll: Error: " << err
+ << " avail_out: " << uncomp_stream_.avail_out;
+ UncompressErrorInit();
+ return err;
+ } else if (uncomp_stream_.avail_out == 0) {
+ err = Z_BUF_ERROR;
+ }
+
+ assert(err == Z_OK || err == Z_BUF_ERROR || err == Z_STREAM_END);
+ if (err == Z_STREAM_END)
+ err = Z_OK;
+
+ *destLen = uncomp_stream_.total_out - old_total_out; // size for this call
+
+ return err;
+}
+
+int ZLib::UncompressChunkOrAll(Bytef *dest, uLongf *destLen,
+ const Bytef *source, uLong sourceLen,
+ int flush_mode) { // Z_SYNC_FLUSH or Z_FINISH
+ const int ret =
+ UncompressAtMostOrAll(dest, destLen, source, &sourceLen, flush_mode);
+ if (ret == Z_BUF_ERROR)
+ UncompressErrorInit();
+ return ret;
+}
+
+int ZLib::UncompressAtMost(Bytef *dest, uLongf *destLen,
+ const Bytef *source, uLong *sourceLen) {
+ return UncompressAtMostOrAll(dest, destLen, source, sourceLen, Z_SYNC_FLUSH);
+}
+
+// We make sure we've uncompressed everything, that is, the current
+// uncompress stream is at a compressed-buffer-EOF boundary. In gzip
+// mode, we also check the gzip footer to make sure we pass the gzip
+// consistency checks. We RETURN true iff both types of checks pass.
+bool ZLib::UncompressChunkDone() {
+ assert(!first_chunk_ && uncomp_init_);
+ // Make sure we're at the end-of-compressed-data point. This means
+ // if we call inflate with Z_FINISH we won't consume any input or
+ // write any output
+ Bytef dummyin, dummyout;
+ uLongf dummylen = 0;
+ if ( UncompressChunkOrAll(&dummyout, &dummylen, &dummyin, 0, Z_FINISH)
+ != Z_OK ) {
+ return false;
+ }
+
+ // Make sure that when we exit, we can start a new round of chunks later
+ Reset();
+
+ return true;
+}
+
+// Uncompresses the source buffer into the destination buffer.
+// The destination buffer must be long enough to hold the entire
+// decompressed contents.
+//
+// We only initialize the uncomp_stream once. Thereafter, we use
+// inflateReset, which should be faster.
+//
+// Returns Z_OK on success, otherwise, it returns a zlib error code.
+int ZLib::Uncompress(Bytef *dest, uLongf *destLen,
+ const Bytef *source, uLong sourceLen) {
+ int err;
+ if ( (err=UncompressChunkOrAll(dest, destLen, source, sourceLen,
+ Z_FINISH)) != Z_OK ) {
+ Reset(); // let us try to compress again
+ return err;
+ }
+ if ( !UncompressChunkDone() ) // calls Reset()
+ return Z_DATA_ERROR;
+ return Z_OK; // stream_end is ok
+}
+
+#endif // HAVE_LIBZ
+
+} // namespace snappy
diff --git a/app/snappy/snappy-test.h b/app/snappy/snappy-test.h
new file mode 100644
index 00000000..f7ba79ed
--- /dev/null
+++ b/app/snappy/snappy-test.h
@@ -0,0 +1,580 @@
+// Copyright 2011 Google Inc. All Rights Reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+// Various stubs for the unit tests for the open-source version of Snappy.
+
+#ifndef UTIL_SNAPPY_OPENSOURCE_SNAPPY_TEST_H_
+#define UTIL_SNAPPY_OPENSOURCE_SNAPPY_TEST_H_
+
+#include <iostream>
+#include <string>
+
+#include "snappy-stubs-internal.h"
+
+#include <stdio.h>
+#include <stdarg.h>
+
+#ifdef HAVE_SYS_MMAN_H
+#include <sys/mman.h>
+#endif
+
+#ifdef HAVE_SYS_RESOURCE_H
+#include <sys/resource.h>
+#endif
+
+#ifdef HAVE_SYS_TIME_H
+#include <sys/time.h>
+#endif
+
+#ifdef HAVE_WINDOWS_H
+#define WIN32_LEAN_AND_MEAN
+#include <windows.h>
+#endif
+
+#include <string>
+
+#ifdef HAVE_GTEST
+
+#include <gtest/gtest.h>
+#undef TYPED_TEST
+#define TYPED_TEST TEST
+#define INIT_GTEST(argc, argv) ::testing::InitGoogleTest(argc, *argv)
+
+#else
+
+// Stubs for if the user doesn't have Google Test installed.
+
+#define TEST(test_case, test_subcase) \
+ void Test_ ## test_case ## _ ## test_subcase()
+#define INIT_GTEST(argc, argv)
+
+#define TYPED_TEST TEST
+#define EXPECT_EQ CHECK_EQ
+#define EXPECT_NE CHECK_NE
+#define EXPECT_FALSE(cond) CHECK(!(cond))
+
+#endif
+
+#ifdef HAVE_GFLAGS
+
+#include <gflags/gflags.h>
+
+// This is tricky; both gflags and Google Test want to look at the command line
+// arguments. Google Test seems to be the most happy with unknown arguments,
+// though, so we call it first and hope for the best.
+#define InitGoogle(argv0, argc, argv, remove_flags) \
+ INIT_GTEST(argc, argv); \
+ google::ParseCommandLineFlags(argc, argv, remove_flags);
+
+#else
+
+// If we don't have the gflags package installed, these can only be
+// changed at compile time.
+#define DEFINE_int32(flag_name, default_value, description) \
+ static int FLAGS_ ## flag_name = default_value;
+
+#define InitGoogle(argv0, argc, argv, remove_flags) \
+ INIT_GTEST(argc, argv)
+
+#endif
+
+#ifdef HAVE_LIBZ
+#include "zlib.h"
+#endif
+
+#ifdef HAVE_LIBLZO2
+#include "lzo/lzo1x.h"
+#endif
+
+#ifdef HAVE_LIBLZF
+extern "C" {
+#include "lzf.h"
+}
+#endif
+
+#ifdef HAVE_LIBFASTLZ
+#include "fastlz.h"
+#endif
+
+#ifdef HAVE_LIBQUICKLZ
+#include "quicklz.h"
+#endif
+
+namespace {
+
+namespace File {
+ void Init() { }
+} // namespace File
+
+namespace file {
+ int Defaults() { }
+
+ class DummyStatus {
+ public:
+ void CheckSuccess() { }
+ };
+
+ DummyStatus GetContents(const string& filename, string* data, int unused) {
+ FILE* fp = fopen(filename.c_str(), "rb");
+ if (fp == NULL) {
+ perror(filename.c_str());
+ exit(1);
+ }
+
+ data->clear();
+ while (!feof(fp)) {
+ char buf[4096];
+ size_t ret = fread(buf, 1, 4096, fp);
+ if (ret == 0 && ferror(fp)) {
+ perror("fread");
+ exit(1);
+ }
+ data->append(string(buf, ret));
+ }
+
+ fclose(fp);
+ }
+
+ DummyStatus SetContents(const string& filename,
+ const string& str,
+ int unused) {
+ FILE* fp = fopen(filename.c_str(), "wb");
+ if (fp == NULL) {
+ perror(filename.c_str());
+ exit(1);
+ }
+
+ int ret = fwrite(str.data(), str.size(), 1, fp);
+ if (ret != 1) {
+ perror("fwrite");
+ exit(1);
+ }
+
+ fclose(fp);
+ }
+} // namespace file
+
+} // namespace
+
+namespace snappy {
+
+#define FLAGS_test_random_seed 301
+typedef string TypeParam;
+
+void Test_CorruptedTest_VerifyCorrupted();
+void Test_Snappy_SimpleTests();
+void Test_Snappy_MaxBlowup();
+void Test_Snappy_RandomData();
+void Test_Snappy_FourByteOffset();
+void Test_SnappyCorruption_TruncatedVarint();
+void Test_SnappyCorruption_UnterminatedVarint();
+void Test_Snappy_ReadPastEndOfBuffer();
+void Test_Snappy_FindMatchLength();
+void Test_Snappy_FindMatchLengthRandom();
+
+string ReadTestDataFile(const string& base, size_t size_limit);
+
+string ReadTestDataFile(const string& base);
+
+// A sprintf() variant that returns a std::string.
+// Not safe for general use due to truncation issues.
+string StringPrintf(const char* format, ...);
+
+// A simple, non-cryptographically-secure random generator.
+class ACMRandom {
+ public:
+ explicit ACMRandom(uint32 seed) : seed_(seed) {}
+
+ int32 Next();
+
+ int32 Uniform(int32 n) {
+ return Next() % n;
+ }
+ uint8 Rand8() {
+ return static_cast<uint8>((Next() >> 1) & 0x000000ff);
+ }
+ bool OneIn(int X) { return Uniform(X) == 0; }
+
+ // Skewed: pick "base" uniformly from range [0,max_log] and then
+ // return "base" random bits. The effect is to pick a number in the
+ // range [0,2^max_log-1] with bias towards smaller numbers.
+ int32 Skewed(int max_log);
+
+ private:
+ static const uint32 M = 2147483647L; // 2^31-1
+ uint32 seed_;
+};
+
+inline int32 ACMRandom::Next() {
+ static const uint64 A = 16807; // bits 14, 8, 7, 5, 2, 1, 0
+ // We are computing
+ // seed_ = (seed_ * A) % M, where M = 2^31-1
+ //
+ // seed_ must not be zero or M, or else all subsequent computed values
+ // will be zero or M respectively. For all other values, seed_ will end
+ // up cycling through every number in [1,M-1]
+ uint64 product = seed_ * A;
+
+ // Compute (product % M) using the fact that ((x << 31) % M) == x.
+ seed_ = (product >> 31) + (product & M);
+ // The first reduction may overflow by 1 bit, so we may need to repeat.
+ // mod == M is not possible; using > allows the faster sign-bit-based test.
+ if (seed_ > M) {
+ seed_ -= M;
+ }
+ return seed_;
+}
+
+inline int32 ACMRandom::Skewed(int max_log) {
+ const int32 base = (Next() - 1) % (max_log+1);
+ return (Next() - 1) & ((1u << base)-1);
+}
+
+// A wall-time clock. This stub is not super-accurate, nor resistant to the
+// system time changing.
+class CycleTimer {
+ public:
+ CycleTimer() : real_time_us_(0) {}
+
+ void Start() {
+#ifdef WIN32
+ QueryPerformanceCounter(&start_);
+#else
+ gettimeofday(&start_, NULL);
+#endif
+ }
+
+ void Stop() {
+#ifdef WIN32
+ LARGE_INTEGER stop;
+ LARGE_INTEGER frequency;
+ QueryPerformanceCounter(&stop);
+ QueryPerformanceFrequency(&frequency);
+
+ double elapsed = static_cast<double>(stop.QuadPart - start_.QuadPart) /
+ frequency.QuadPart;
+ real_time_us_ += elapsed * 1e6 + 0.5;
+#else
+ struct timeval stop;
+ gettimeofday(&stop, NULL);
+
+ real_time_us_ += 1000000 * (stop.tv_sec - start_.tv_sec);
+ real_time_us_ += (stop.tv_usec - start_.tv_usec);
+#endif
+ }
+
+ double Get() {
+ return real_time_us_ * 1e-6;
+ }
+
+ private:
+ int64 real_time_us_;
+#ifdef WIN32
+ LARGE_INTEGER start_;
+#else
+ struct timeval start_;
+#endif
+};
+
+// Minimalistic microbenchmark framework.
+
+typedef void (*BenchmarkFunction)(int, int);
+
+class Benchmark {
+ public:
+ Benchmark(const string& name, BenchmarkFunction function) :
+ name_(name), function_(function) {}
+
+ Benchmark* DenseRange(int start, int stop) {
+ start_ = start;
+ stop_ = stop;
+ return this;
+ }
+
+ void Run();
+
+ private:
+ const string name_;
+ const BenchmarkFunction function_;
+ int start_, stop_;
+};
+#define BENCHMARK(benchmark_name) \
+ Benchmark* Benchmark_ ## benchmark_name = \
+ (new Benchmark(#benchmark_name, benchmark_name))
+
+extern Benchmark* Benchmark_BM_UFlat;
+extern Benchmark* Benchmark_BM_UValidate;
+extern Benchmark* Benchmark_BM_ZFlat;
+
+void ResetBenchmarkTiming();
+void StartBenchmarkTiming();
+void StopBenchmarkTiming();
+void SetBenchmarkLabel(const string& str);
+void SetBenchmarkBytesProcessed(int64 bytes);
+
+#ifdef HAVE_LIBZ
+
+// Object-oriented wrapper around zlib.
+class ZLib {
+ public:
+ ZLib();
+ ~ZLib();
+
+ // Wipe a ZLib object to a virgin state. This differs from Reset()
+ // in that it also breaks any state.
+ void Reinit();
+
+ // Call this to make a zlib buffer as good as new. Here's the only
+ // case where they differ:
+ // CompressChunk(a); CompressChunk(b); CompressChunkDone(); vs
+ // CompressChunk(a); Reset(); CompressChunk(b); CompressChunkDone();
+ // You'll want to use Reset(), then, when you interrupt a compress
+ // (or uncompress) in the middle of a chunk and want to start over.
+ void Reset();
+
+ // According to the zlib manual, when you Compress, the destination
+ // buffer must have size at least src + .1%*src + 12. This function
+ // helps you calculate that. Augment this to account for a potential
+ // gzip header and footer, plus a few bytes of slack.
+ static int MinCompressbufSize(int uncompress_size) {
+ return uncompress_size + uncompress_size/1000 + 40;
+ }
+
+ // Compresses the source buffer into the destination buffer.
+ // sourceLen is the byte length of the source buffer.
+ // Upon entry, destLen is the total size of the destination buffer,
+ // which must be of size at least MinCompressbufSize(sourceLen).
+ // Upon exit, destLen is the actual size of the compressed buffer.
+ //
+ // This function can be used to compress a whole file at once if the
+ // input file is mmap'ed.
+ //
+ // Returns Z_OK if success, Z_MEM_ERROR if there was not
+ // enough memory, Z_BUF_ERROR if there was not enough room in the
+ // output buffer. Note that if the output buffer is exactly the same
+ // size as the compressed result, we still return Z_BUF_ERROR.
+ // (check CL#1936076)
+ int Compress(Bytef *dest, uLongf *destLen,
+ const Bytef *source, uLong sourceLen);
+
+ // Uncompresses the source buffer into the destination buffer.
+ // The destination buffer must be long enough to hold the entire
+ // decompressed contents.
+ //
+ // Returns Z_OK on success, otherwise, it returns a zlib error code.
+ int Uncompress(Bytef *dest, uLongf *destLen,
+ const Bytef *source, uLong sourceLen);
+
+ // Uncompress data one chunk at a time -- ie you can call this
+ // more than once. To get this to work you need to call per-chunk
+ // and "done" routines.
+ //
+ // Returns Z_OK if success, Z_MEM_ERROR if there was not
+ // enough memory, Z_BUF_ERROR if there was not enough room in the
+ // output buffer.
+
+ int UncompressAtMost(Bytef *dest, uLongf *destLen,
+ const Bytef *source, uLong *sourceLen);
+
+ // Checks gzip footer information, as needed. Mostly this just
+ // makes sure the checksums match. Whenever you call this, it
+ // will assume the last 8 bytes from the previous UncompressChunk
+ // call are the footer. Returns true iff everything looks ok.
+ bool UncompressChunkDone();
+
+ private:
+ int InflateInit(); // sets up the zlib inflate structure
+ int DeflateInit(); // sets up the zlib deflate structure
+
+ // These init the zlib data structures for compressing/uncompressing
+ int CompressInit(Bytef *dest, uLongf *destLen,
+ const Bytef *source, uLong *sourceLen);
+ int UncompressInit(Bytef *dest, uLongf *destLen,
+ const Bytef *source, uLong *sourceLen);
+ // Initialization method to be called if we hit an error while
+ // uncompressing. On hitting an error, call this method before
+ // returning the error.
+ void UncompressErrorInit();
+
+ // Helper function for Compress
+ int CompressChunkOrAll(Bytef *dest, uLongf *destLen,
+ const Bytef *source, uLong sourceLen,
+ int flush_mode);
+ int CompressAtMostOrAll(Bytef *dest, uLongf *destLen,
+ const Bytef *source, uLong *sourceLen,
+ int flush_mode);
+
+ // Likewise for UncompressAndUncompressChunk
+ int UncompressChunkOrAll(Bytef *dest, uLongf *destLen,
+ const Bytef *source, uLong sourceLen,
+ int flush_mode);
+
+ int UncompressAtMostOrAll(Bytef *dest, uLongf *destLen,
+ const Bytef *source, uLong *sourceLen,
+ int flush_mode);
+
+ // Initialization method to be called if we hit an error while
+ // compressing. On hitting an error, call this method before
+ // returning the error.
+ void CompressErrorInit();
+
+ int compression_level_; // compression level
+ int window_bits_; // log base 2 of the window size used in compression
+ int mem_level_; // specifies the amount of memory to be used by
+ // compressor (1-9)
+ z_stream comp_stream_; // Zlib stream data structure
+ bool comp_init_; // True if we have initialized comp_stream_
+ z_stream uncomp_stream_; // Zlib stream data structure
+ bool uncomp_init_; // True if we have initialized uncomp_stream_
+
+ // These are used only with chunked compression.
+ bool first_chunk_; // true if we need to emit headers with this chunk
+};
+
+#endif // HAVE_LIBZ
+
+} // namespace snappy
+
+DECLARE_bool(run_microbenchmarks);
+
+static void RunSpecifiedBenchmarks() {
+ if (!FLAGS_run_microbenchmarks) {
+ return;
+ }
+
+ fprintf(stderr, "Running microbenchmarks.\n");
+#ifndef NDEBUG
+ fprintf(stderr, "WARNING: Compiled with assertions enabled, will be slow.\n");
+#endif
+#ifndef __OPTIMIZE__
+ fprintf(stderr, "WARNING: Compiled without optimization, will be slow.\n");
+#endif
+ fprintf(stderr, "Benchmark Time(ns) CPU(ns) Iterations\n");
+ fprintf(stderr, "---------------------------------------------------\n");
+
+ snappy::Benchmark_BM_UFlat->Run();
+ snappy::Benchmark_BM_UValidate->Run();
+ snappy::Benchmark_BM_ZFlat->Run();
+
+ fprintf(stderr, "\n");
+}
+
+#ifndef HAVE_GTEST
+
+static inline int RUN_ALL_TESTS() {
+ fprintf(stderr, "Running correctness tests.\n");
+ snappy::Test_CorruptedTest_VerifyCorrupted();
+ snappy::Test_Snappy_SimpleTests();
+ snappy::Test_Snappy_MaxBlowup();
+ snappy::Test_Snappy_RandomData();
+ snappy::Test_Snappy_FourByteOffset();
+ snappy::Test_SnappyCorruption_TruncatedVarint();
+ snappy::Test_SnappyCorruption_UnterminatedVarint();
+ snappy::Test_Snappy_ReadPastEndOfBuffer();
+ snappy::Test_Snappy_FindMatchLength();
+ snappy::Test_Snappy_FindMatchLengthRandom();
+ fprintf(stderr, "All tests passed.\n");
+
+ return 0;
+}
+
+#endif // HAVE_GTEST
+
+// For main().
+namespace snappy {
+
+static void CompressFile(const char* fname);
+static void UncompressFile(const char* fname);
+static void MeasureFile(const char* fname);
+
+// Logging.
+
+#define LOG(level) LogMessage()
+#define VLOG(level) true ? (void)0 : \
+ snappy::LogMessageVoidify() & snappy::LogMessage()
+
+class LogMessage {
+ public:
+ LogMessage() { }
+ ~LogMessage() {
+ cerr << endl;
+ }
+
+ LogMessage& operator<<(const std::string& msg) {
+ cerr << msg;
+ return *this;
+ }
+ LogMessage& operator<<(int x) {
+ cerr << x;
+ return *this;
+ }
+};
+
+// Asserts, both versions activated in debug mode only,
+// and ones that are always active.
+
+#define CRASH_UNLESS(condition) \
+ PREDICT_TRUE(condition) ? (void)0 : \
+ snappy::LogMessageVoidify() & snappy::LogMessageCrash()
+
+class LogMessageCrash : public LogMessage {
+ public:
+ LogMessageCrash() { }
+ ~LogMessageCrash() {
+ cerr << endl;
+ abort();
+ }
+};
+
+// This class is used to explicitly ignore values in the conditional
+// logging macros. This avoids compiler warnings like "value computed
+// is not used" and "statement has no effect".
+
+class LogMessageVoidify {
+ public:
+ LogMessageVoidify() { }
+ // This has to be an operator with a precedence lower than << but
+ // higher than ?:
+ void operator&(const LogMessage&) { }
+};
+
+#define CHECK(cond) CRASH_UNLESS(cond)
+#define CHECK_LE(a, b) CRASH_UNLESS((a) <= (b))
+#define CHECK_GE(a, b) CRASH_UNLESS((a) >= (b))
+#define CHECK_EQ(a, b) CRASH_UNLESS((a) == (b))
+#define CHECK_NE(a, b) CRASH_UNLESS((a) != (b))
+#define CHECK_LT(a, b) CRASH_UNLESS((a) < (b))
+#define CHECK_GT(a, b) CRASH_UNLESS((a) > (b))
+
+} // namespace
+
+using snappy::CompressFile;
+using snappy::UncompressFile;
+using snappy::MeasureFile;
+
+#endif // UTIL_SNAPPY_OPENSOURCE_SNAPPY_TEST_H_
diff --git a/app/snappy/snappy.cc b/app/snappy/snappy.cc
new file mode 100644
index 00000000..1230321f
--- /dev/null
+++ b/app/snappy/snappy.cc
@@ -0,0 +1,1119 @@
+// Copyright 2005 Google Inc. All Rights Reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "snappy.h"
+#include "snappy-internal.h"
+#include "snappy-sinksource.h"
+
+#include <stdio.h>
+
+#include <algorithm>
+#include <string>
+#include <vector>
+
+
+namespace snappy {
+
+// Any hash function will produce a valid compressed bitstream, but a good
+// hash function reduces the number of collisions and thus yields better
+// compression for compressible input, and more speed for incompressible
+// input. Of course, it doesn't hurt if the hash function is reasonably fast
+// either, as it gets called a lot.
+static inline uint32 HashBytes(uint32 bytes, int shift) {
+ uint32 kMul = 0x1e35a7bd;
+ return (bytes * kMul) >> shift;
+}
+static inline uint32 Hash(const char* p, int shift) {
+ return HashBytes(UNALIGNED_LOAD32(p), shift);
+}
+
+size_t MaxCompressedLength(size_t source_len) {
+ // Compressed data can be defined as:
+ // compressed := item* literal*
+ // item := literal* copy
+ //
+ // The trailing literal sequence has a space blowup of at most 62/60
+ // since a literal of length 60 needs one tag byte + one extra byte
+ // for length information.
+ //
+ // Item blowup is trickier to measure. Suppose the "copy" op copies
+ // 4 bytes of data. Because of a special check in the encoding code,
+ // we produce a 4-byte copy only if the offset is < 65536. Therefore
+ // the copy op takes 3 bytes to encode, and this type of item leads
+ // to at most the 62/60 blowup for representing literals.
+ //
+ // Suppose the "copy" op copies 5 bytes of data. If the offset is big
+ // enough, it will take 5 bytes to encode the copy op. Therefore the
+ // worst case here is a one-byte literal followed by a five-byte copy.
+ // I.e., 6 bytes of input turn into 7 bytes of "compressed" data.
+ //
+ // This last factor dominates the blowup, so the final estimate is:
+ return 32 + source_len + source_len/6;
+}
+
+enum {
+ LITERAL = 0,
+ COPY_1_BYTE_OFFSET = 1, // 3 bit length + 3 bits of offset in opcode
+ COPY_2_BYTE_OFFSET = 2,
+ COPY_4_BYTE_OFFSET = 3
+};
+
+// Copy "len" bytes from "src" to "op", one byte at a time. Used for
+// handling COPY operations where the input and output regions may
+// overlap. For example, suppose:
+// src == "ab"
+// op == src + 2
+// len == 20
+// After IncrementalCopy(src, op, len), the result will have
+// eleven copies of "ab"
+// ababababababababababab
+// Note that this does not match the semantics of either memcpy()
+// or memmove().
+static inline void IncrementalCopy(const char* src, char* op, int len) {
+ assert(len > 0);
+ do {
+ *op++ = *src++;
+ } while (--len > 0);
+}
+
+// Equivalent to IncrementalCopy except that it can write up to ten extra
+// bytes after the end of the copy, and that it is faster.
+//
+// The main part of this loop is a simple copy of eight bytes at a time until
+// we've copied (at least) the requested amount of bytes. However, if op and
+// src are less than eight bytes apart (indicating a repeating pattern of
+// length < 8), we first need to expand the pattern in order to get the correct
+// results. For instance, if the buffer looks like this, with the eight-byte
+// <src> and <op> patterns marked as intervals:
+//
+// abxxxxxxxxxxxx
+// [------] src
+// [------] op
+//
+// a single eight-byte copy from <src> to <op> will repeat the pattern once,
+// after which we can move <op> two bytes without moving <src>:
+//
+// ababxxxxxxxxxx
+// [------] src
+// [------] op
+//
+// and repeat the exercise until the two no longer overlap.
+//
+// This allows us to do very well in the special case of one single byte
+// repeated many times, without taking a big hit for more general cases.
+//
+// The worst case of extra writing past the end of the match occurs when
+// op - src == 1 and len == 1; the last copy will read from byte positions
+// [0..7] and write to [4..11], whereas it was only supposed to write to
+// position 1. Thus, ten excess bytes.
+
+namespace {
+
+const int kMaxIncrementCopyOverflow = 10;
+
+} // namespace
+
+static inline void IncrementalCopyFastPath(const char* src, char* op, int len) {
+ while (op - src < 8) {
+ UnalignedCopy64(src, op);
+ len -= op - src;
+ op += op - src;
+ }
+ while (len > 0) {
+ UnalignedCopy64(src, op);
+ src += 8;
+ op += 8;
+ len -= 8;
+ }
+}
+
+static inline char* EmitLiteral(char* op,
+ const char* literal,
+ int len,
+ bool allow_fast_path) {
+ int n = len - 1; // Zero-length literals are disallowed
+ if (n < 60) {
+ // Fits in tag byte
+ *op++ = LITERAL | (n << 2);
+
+ // The vast majority of copies are below 16 bytes, for which a
+ // call to memcpy is overkill. This fast path can sometimes
+ // copy up to 15 bytes too much, but that is okay in the
+ // main loop, since we have a bit to go on for both sides:
+ //
+ // - The input will always have kInputMarginBytes = 15 extra
+ // available bytes, as long as we're in the main loop, and
+ // if not, allow_fast_path = false.
+ // - The output will always have 32 spare bytes (see
+ // MaxCompressedLength).
+ if (allow_fast_path && len <= 16) {
+ UnalignedCopy64(literal, op);
+ UnalignedCopy64(literal + 8, op + 8);
+ return op + len;
+ }
+ } else {
+ // Encode in upcoming bytes
+ char* base = op;
+ int count = 0;
+ op++;
+ while (n > 0) {
+ *op++ = n & 0xff;
+ n >>= 8;
+ count++;
+ }
+ assert(count >= 1);
+ assert(count <= 4);
+ *base = LITERAL | ((59+count) << 2);
+ }
+ memcpy(op, literal, len);
+ return op + len;
+}
+
+static inline char* EmitCopyLessThan64(char* op, size_t offset, int len) {
+ assert(len <= 64);
+ assert(len >= 4);
+ assert(offset < 65536);
+
+ if ((len < 12) && (offset < 2048)) {
+ size_t len_minus_4 = len - 4;
+ assert(len_minus_4 < 8); // Must fit in 3 bits
+ *op++ = COPY_1_BYTE_OFFSET + ((len_minus_4) << 2) + ((offset >> 8) << 5);
+ *op++ = offset & 0xff;
+ } else {
+ *op++ = COPY_2_BYTE_OFFSET + ((len-1) << 2);
+ LittleEndian::Store16(op, offset);
+ op += 2;
+ }
+ return op;
+}
+
+static inline char* EmitCopy(char* op, size_t offset, int len) {
+ // Emit 64 byte copies but make sure to keep at least four bytes reserved
+ while (len >= 68) {
+ op = EmitCopyLessThan64(op, offset, 64);
+ len -= 64;
+ }
+
+ // Emit an extra 60 byte copy if have too much data to fit in one copy
+ if (len > 64) {
+ op = EmitCopyLessThan64(op, offset, 60);
+ len -= 60;
+ }
+
+ // Emit remainder
+ op = EmitCopyLessThan64(op, offset, len);
+ return op;
+}
+
+
+bool GetUncompressedLength(const char* start, size_t n, size_t* result) {
+ uint32 v = 0;
+ const char* limit = start + n;
+ if (Varint::Parse32WithLimit(start, limit, &v) != NULL) {
+ *result = v;
+ return true;
+ } else {
+ return false;
+ }
+}
+
+namespace internal {
+uint16* WorkingMemory::GetHashTable(size_t input_size, int* table_size) {
+ // Use smaller hash table when input.size() is smaller, since we
+ // fill the table, incurring O(hash table size) overhead for
+ // compression, and if the input is short, we won't need that
+ // many hash table entries anyway.
+ assert(kMaxHashTableSize >= 256);
+ size_t htsize = 256;
+ while (htsize < kMaxHashTableSize && htsize < input_size) {
+ htsize <<= 1;
+ }
+
+ uint16* table;
+ if (htsize <= ARRAYSIZE(small_table_)) {
+ table = small_table_;
+ } else {
+ if (large_table_ == NULL) {
+ large_table_ = new uint16[kMaxHashTableSize];
+ }
+ table = large_table_;
+ }
+
+ *table_size = htsize;
+ memset(table, 0, htsize * sizeof(*table));
+ return table;
+}
+} // end namespace internal
+
+// For 0 <= offset <= 4, GetUint32AtOffset(GetEightBytesAt(p), offset) will
+// equal UNALIGNED_LOAD32(p + offset). Motivation: On x86-64 hardware we have
+// empirically found that overlapping loads such as
+// UNALIGNED_LOAD32(p) ... UNALIGNED_LOAD32(p+1) ... UNALIGNED_LOAD32(p+2)
+// are slower than UNALIGNED_LOAD64(p) followed by shifts and casts to uint32.
+//
+// We have different versions for 64- and 32-bit; ideally we would avoid the
+// two functions and just inline the UNALIGNED_LOAD64 call into
+// GetUint32AtOffset, but GCC (at least not as of 4.6) is seemingly not clever
+// enough to avoid loading the value multiple times then. For 64-bit, the load
+// is done when GetEightBytesAt() is called, whereas for 32-bit, the load is
+// done at GetUint32AtOffset() time.
+
+#ifdef ARCH_K8
+
+typedef uint64 EightBytesReference;
+
+static inline EightBytesReference GetEightBytesAt(const char* ptr) {
+ return UNALIGNED_LOAD64(ptr);
+}
+
+static inline uint32 GetUint32AtOffset(uint64 v, int offset) {
+ assert(offset >= 0);
+ assert(offset <= 4);
+ return v >> (LittleEndian::IsLittleEndian() ? 8 * offset : 32 - 8 * offset);
+}
+
+#else
+
+typedef const char* EightBytesReference;
+
+static inline EightBytesReference GetEightBytesAt(const char* ptr) {
+ return ptr;
+}
+
+static inline uint32 GetUint32AtOffset(const char* v, int offset) {
+ assert(offset >= 0);
+ assert(offset <= 4);
+ return UNALIGNED_LOAD32(v + offset);
+}
+
+#endif
+
+// Flat array compression that does not emit the "uncompressed length"
+// prefix. Compresses "input" string to the "*op" buffer.
+//
+// REQUIRES: "input" is at most "kBlockSize" bytes long.
+// REQUIRES: "op" points to an array of memory that is at least
+// "MaxCompressedLength(input.size())" in size.
+// REQUIRES: All elements in "table[0..table_size-1]" are initialized to zero.
+// REQUIRES: "table_size" is a power of two
+//
+// Returns an "end" pointer into "op" buffer.
+// "end - op" is the compressed size of "input".
+namespace internal {
+char* CompressFragment(const char* input,
+ size_t input_size,
+ char* op,
+ uint16* table,
+ const int table_size) {
+ // "ip" is the input pointer, and "op" is the output pointer.
+ const char* ip = input;
+ assert(input_size <= kBlockSize);
+ assert((table_size & (table_size - 1)) == 0); // table must be power of two
+ const int shift = 32 - Bits::Log2Floor(table_size);
+ assert(static_cast<int>(kuint32max >> shift) == table_size - 1);
+ const char* ip_end = input + input_size;
+ const char* base_ip = ip;
+ // Bytes in [next_emit, ip) will be emitted as literal bytes. Or
+ // [next_emit, ip_end) after the main loop.
+ const char* next_emit = ip;
+
+ const size_t kInputMarginBytes = 15;
+ if (PREDICT_TRUE(input_size >= kInputMarginBytes)) {
+ const char* ip_limit = input + input_size - kInputMarginBytes;
+
+ for (uint32 next_hash = Hash(++ip, shift); ; ) {
+ assert(next_emit < ip);
+ // The body of this loop calls EmitLiteral once and then EmitCopy one or
+ // more times. (The exception is that when we're close to exhausting
+ // the input we goto emit_remainder.)
+ //
+ // In the first iteration of this loop we're just starting, so
+ // there's nothing to copy, so calling EmitLiteral once is
+ // necessary. And we only start a new iteration when the
+ // current iteration has determined that a call to EmitLiteral will
+ // precede the next call to EmitCopy (if any).
+ //
+ // Step 1: Scan forward in the input looking for a 4-byte-long match.
+ // If we get close to exhausting the input then goto emit_remainder.
+ //
+ // Heuristic match skipping: If 32 bytes are scanned with no matches
+ // found, start looking only at every other byte. If 32 more bytes are
+ // scanned, look at every third byte, etc.. When a match is found,
+ // immediately go back to looking at every byte. This is a small loss
+ // (~5% performance, ~0.1% density) for compressible data due to more
+ // bookkeeping, but for non-compressible data (such as JPEG) it's a huge
+ // win since the compressor quickly "realizes" the data is incompressible
+ // and doesn't bother looking for matches everywhere.
+ //
+ // The "skip" variable keeps track of how many bytes there are since the
+ // last match; dividing it by 32 (ie. right-shifting by five) gives the
+ // number of bytes to move ahead for each iteration.
+ uint32 skip = 32;
+
+ const char* next_ip = ip;
+ const char* candidate;
+ do {
+ ip = next_ip;
+ uint32 hash = next_hash;
+ assert(hash == Hash(ip, shift));
+ uint32 bytes_between_hash_lookups = skip++ >> 5;
+ next_ip = ip + bytes_between_hash_lookups;
+ if (PREDICT_FALSE(next_ip > ip_limit)) {
+ goto emit_remainder;
+ }
+ next_hash = Hash(next_ip, shift);
+ candidate = base_ip + table[hash];
+ assert(candidate >= base_ip);
+ assert(candidate < ip);
+
+ table[hash] = ip - base_ip;
+ } while (PREDICT_TRUE(UNALIGNED_LOAD32(ip) !=
+ UNALIGNED_LOAD32(candidate)));
+
+ // Step 2: A 4-byte match has been found. We'll later see if more
+ // than 4 bytes match. But, prior to the match, input
+ // bytes [next_emit, ip) are unmatched. Emit them as "literal bytes."
+ assert(next_emit + 16 <= ip_end);
+ op = EmitLiteral(op, next_emit, ip - next_emit, true);
+
+ // Step 3: Call EmitCopy, and then see if another EmitCopy could
+ // be our next move. Repeat until we find no match for the
+ // input immediately after what was consumed by the last EmitCopy call.
+ //
+ // If we exit this loop normally then we need to call EmitLiteral next,
+ // though we don't yet know how big the literal will be. We handle that
+ // by proceeding to the next iteration of the main loop. We also can exit
+ // this loop via goto if we get close to exhausting the input.
+ EightBytesReference input_bytes;
+ uint32 candidate_bytes = 0;
+
+ do {
+ // We have a 4-byte match at ip, and no need to emit any
+ // "literal bytes" prior to ip.
+ const char* base = ip;
+ int matched = 4 + FindMatchLength(candidate + 4, ip + 4, ip_end);
+ ip += matched;
+ size_t offset = base - candidate;
+ assert(0 == memcmp(base, candidate, matched));
+ op = EmitCopy(op, offset, matched);
+ // We could immediately start working at ip now, but to improve
+ // compression we first update table[Hash(ip - 1, ...)].
+ const char* insert_tail = ip - 1;
+ next_emit = ip;
+ if (PREDICT_FALSE(ip >= ip_limit)) {
+ goto emit_remainder;
+ }
+ input_bytes = GetEightBytesAt(insert_tail);
+ uint32 prev_hash = HashBytes(GetUint32AtOffset(input_bytes, 0), shift);
+ table[prev_hash] = ip - base_ip - 1;
+ uint32 cur_hash = HashBytes(GetUint32AtOffset(input_bytes, 1), shift);
+ candidate = base_ip + table[cur_hash];
+ candidate_bytes = UNALIGNED_LOAD32(candidate);
+ table[cur_hash] = ip - base_ip;
+ } while (GetUint32AtOffset(input_bytes, 1) == candidate_bytes);
+
+ next_hash = HashBytes(GetUint32AtOffset(input_bytes, 2), shift);
+ ++ip;
+ }
+ }
+
+ emit_remainder:
+ // Emit the remaining bytes as a literal
+ if (next_emit < ip_end) {
+ op = EmitLiteral(op, next_emit, ip_end - next_emit, false);
+ }
+
+ return op;
+}
+} // end namespace internal
+
+// Signature of output types needed by decompression code.
+// The decompression code is templatized on a type that obeys this
+// signature so that we do not pay virtual function call overhead in
+// the middle of a tight decompression loop.
+//
+// class DecompressionWriter {
+// public:
+// // Called before decompression
+// void SetExpectedLength(size_t length);
+//
+// // Called after decompression
+// bool CheckLength() const;
+//
+// // Called repeatedly during decompression
+// bool Append(const char* ip, size_t length);
+// bool AppendFromSelf(uint32 offset, size_t length);
+//
+// // The difference between TryFastAppend and Append is that TryFastAppend
+// // is allowed to read up to <available> bytes from the input buffer,
+// // whereas Append is allowed to read <length>.
+// //
+// // Also, TryFastAppend is allowed to return false, declining the append,
+// // without it being a fatal error -- just "return false" would be
+// // a perfectly legal implementation of TryFastAppend. The intention
+// // is for TryFastAppend to allow a fast path in the common case of
+// // a small append.
+// //
+// // NOTE(user): TryFastAppend must always return decline (return false)
+// // if <length> is 61 or more, as in this case the literal length is not
+// // decoded fully. In practice, this should not be a big problem,
+// // as it is unlikely that one would implement a fast path accepting
+// // this much data.
+// bool TryFastAppend(const char* ip, size_t available, size_t length);
+// };
+
+// -----------------------------------------------------------------------
+// Lookup table for decompression code. Generated by ComputeTable() below.
+// -----------------------------------------------------------------------
+
+// Mapping from i in range [0,4] to a mask to extract the bottom 8*i bits
+static const uint32 wordmask[] = {
+ 0u, 0xffu, 0xffffu, 0xffffffu, 0xffffffffu
+};
+
+// Data stored per entry in lookup table:
+// Range Bits-used Description
+// ------------------------------------
+// 1..64 0..7 Literal/copy length encoded in opcode byte
+// 0..7 8..10 Copy offset encoded in opcode byte / 256
+// 0..4 11..13 Extra bytes after opcode
+//
+// We use eight bits for the length even though 7 would have sufficed
+// because of efficiency reasons:
+// (1) Extracting a byte is faster than a bit-field
+// (2) It properly aligns copy offset so we do not need a <<8
+static const uint16 char_table[256] = {
+ 0x0001, 0x0804, 0x1001, 0x2001, 0x0002, 0x0805, 0x1002, 0x2002,
+ 0x0003, 0x0806, 0x1003, 0x2003, 0x0004, 0x0807, 0x1004, 0x2004,
+ 0x0005, 0x0808, 0x1005, 0x2005, 0x0006, 0x0809, 0x1006, 0x2006,
+ 0x0007, 0x080a, 0x1007, 0x2007, 0x0008, 0x080b, 0x1008, 0x2008,
+ 0x0009, 0x0904, 0x1009, 0x2009, 0x000a, 0x0905, 0x100a, 0x200a,
+ 0x000b, 0x0906, 0x100b, 0x200b, 0x000c, 0x0907, 0x100c, 0x200c,
+ 0x000d, 0x0908, 0x100d, 0x200d, 0x000e, 0x0909, 0x100e, 0x200e,
+ 0x000f, 0x090a, 0x100f, 0x200f, 0x0010, 0x090b, 0x1010, 0x2010,
+ 0x0011, 0x0a04, 0x1011, 0x2011, 0x0012, 0x0a05, 0x1012, 0x2012,
+ 0x0013, 0x0a06, 0x1013, 0x2013, 0x0014, 0x0a07, 0x1014, 0x2014,
+ 0x0015, 0x0a08, 0x1015, 0x2015, 0x0016, 0x0a09, 0x1016, 0x2016,
+ 0x0017, 0x0a0a, 0x1017, 0x2017, 0x0018, 0x0a0b, 0x1018, 0x2018,
+ 0x0019, 0x0b04, 0x1019, 0x2019, 0x001a, 0x0b05, 0x101a, 0x201a,
+ 0x001b, 0x0b06, 0x101b, 0x201b, 0x001c, 0x0b07, 0x101c, 0x201c,
+ 0x001d, 0x0b08, 0x101d, 0x201d, 0x001e, 0x0b09, 0x101e, 0x201e,
+ 0x001f, 0x0b0a, 0x101f, 0x201f, 0x0020, 0x0b0b, 0x1020, 0x2020,
+ 0x0021, 0x0c04, 0x1021, 0x2021, 0x0022, 0x0c05, 0x1022, 0x2022,
+ 0x0023, 0x0c06, 0x1023, 0x2023, 0x0024, 0x0c07, 0x1024, 0x2024,
+ 0x0025, 0x0c08, 0x1025, 0x2025, 0x0026, 0x0c09, 0x1026, 0x2026,
+ 0x0027, 0x0c0a, 0x1027, 0x2027, 0x0028, 0x0c0b, 0x1028, 0x2028,
+ 0x0029, 0x0d04, 0x1029, 0x2029, 0x002a, 0x0d05, 0x102a, 0x202a,
+ 0x002b, 0x0d06, 0x102b, 0x202b, 0x002c, 0x0d07, 0x102c, 0x202c,
+ 0x002d, 0x0d08, 0x102d, 0x202d, 0x002e, 0x0d09, 0x102e, 0x202e,
+ 0x002f, 0x0d0a, 0x102f, 0x202f, 0x0030, 0x0d0b, 0x1030, 0x2030,
+ 0x0031, 0x0e04, 0x1031, 0x2031, 0x0032, 0x0e05, 0x1032, 0x2032,
+ 0x0033, 0x0e06, 0x1033, 0x2033, 0x0034, 0x0e07, 0x1034, 0x2034,
+ 0x0035, 0x0e08, 0x1035, 0x2035, 0x0036, 0x0e09, 0x1036, 0x2036,
+ 0x0037, 0x0e0a, 0x1037, 0x2037, 0x0038, 0x0e0b, 0x1038, 0x2038,
+ 0x0039, 0x0f04, 0x1039, 0x2039, 0x003a, 0x0f05, 0x103a, 0x203a,
+ 0x003b, 0x0f06, 0x103b, 0x203b, 0x003c, 0x0f07, 0x103c, 0x203c,
+ 0x0801, 0x0f08, 0x103d, 0x203d, 0x1001, 0x0f09, 0x103e, 0x203e,
+ 0x1801, 0x0f0a, 0x103f, 0x203f, 0x2001, 0x0f0b, 0x1040, 0x2040
+};
+
+// In debug mode, allow optional computation of the table at startup.
+// Also, check that the decompression table is correct.
+#ifndef NDEBUG
+DEFINE_bool(snappy_dump_decompression_table, false,
+ "If true, we print the decompression table at startup.");
+
+static uint16 MakeEntry(unsigned int extra,
+ unsigned int len,
+ unsigned int copy_offset) {
+ // Check that all of the fields fit within the allocated space
+ assert(extra == (extra & 0x7)); // At most 3 bits
+ assert(copy_offset == (copy_offset & 0x7)); // At most 3 bits
+ assert(len == (len & 0x7f)); // At most 7 bits
+ return len | (copy_offset << 8) | (extra << 11);
+}
+
+static void ComputeTable() {
+ uint16 dst[256];
+
+ // Place invalid entries in all places to detect missing initialization
+ int assigned = 0;
+ for (int i = 0; i < 256; i++) {
+ dst[i] = 0xffff;
+ }
+
+ // Small LITERAL entries. We store (len-1) in the top 6 bits.
+ for (unsigned int len = 1; len <= 60; len++) {
+ dst[LITERAL | ((len-1) << 2)] = MakeEntry(0, len, 0);
+ assigned++;
+ }
+
+ // Large LITERAL entries. We use 60..63 in the high 6 bits to
+ // encode the number of bytes of length info that follow the opcode.
+ for (unsigned int extra_bytes = 1; extra_bytes <= 4; extra_bytes++) {
+ // We set the length field in the lookup table to 1 because extra
+ // bytes encode len-1.
+ dst[LITERAL | ((extra_bytes+59) << 2)] = MakeEntry(extra_bytes, 1, 0);
+ assigned++;
+ }
+
+ // COPY_1_BYTE_OFFSET.
+ //
+ // The tag byte in the compressed data stores len-4 in 3 bits, and
+ // offset/256 in 5 bits. offset%256 is stored in the next byte.
+ //
+ // This format is used for length in range [4..11] and offset in
+ // range [0..2047]
+ for (unsigned int len = 4; len < 12; len++) {
+ for (unsigned int offset = 0; offset < 2048; offset += 256) {
+ dst[COPY_1_BYTE_OFFSET | ((len-4)<<2) | ((offset>>8)<<5)] =
+ MakeEntry(1, len, offset>>8);
+ assigned++;
+ }
+ }
+
+ // COPY_2_BYTE_OFFSET.
+ // Tag contains len-1 in top 6 bits, and offset in next two bytes.
+ for (unsigned int len = 1; len <= 64; len++) {
+ dst[COPY_2_BYTE_OFFSET | ((len-1)<<2)] = MakeEntry(2, len, 0);
+ assigned++;
+ }
+
+ // COPY_4_BYTE_OFFSET.
+ // Tag contents len-1 in top 6 bits, and offset in next four bytes.
+ for (unsigned int len = 1; len <= 64; len++) {
+ dst[COPY_4_BYTE_OFFSET | ((len-1)<<2)] = MakeEntry(4, len, 0);
+ assigned++;
+ }
+
+ // Check that each entry was initialized exactly once.
+ if (assigned != 256) {
+ fprintf(stderr, "ComputeTable: assigned only %d of 256\n", assigned);
+ abort();
+ }
+ for (int i = 0; i < 256; i++) {
+ if (dst[i] == 0xffff) {
+ fprintf(stderr, "ComputeTable: did not assign byte %d\n", i);
+ abort();
+ }
+ }
+
+ if (FLAGS_snappy_dump_decompression_table) {
+ printf("static const uint16 char_table[256] = {\n ");
+ for (int i = 0; i < 256; i++) {
+ printf("0x%04x%s",
+ dst[i],
+ ((i == 255) ? "\n" : (((i%8) == 7) ? ",\n " : ", ")));
+ }
+ printf("};\n");
+ }
+
+ // Check that computed table matched recorded table
+ for (int i = 0; i < 256; i++) {
+ if (dst[i] != char_table[i]) {
+ fprintf(stderr, "ComputeTable: byte %d: computed (%x), expect (%x)\n",
+ i, static_cast<int>(dst[i]), static_cast<int>(char_table[i]));
+ abort();
+ }
+ }
+}
+#endif /* !NDEBUG */
+
+// Helper class for decompression
+class SnappyDecompressor {
+ private:
+ Source* reader_; // Underlying source of bytes to decompress
+ const char* ip_; // Points to next buffered byte
+ const char* ip_limit_; // Points just past buffered bytes
+ uint32 peeked_; // Bytes peeked from reader (need to skip)
+ bool eof_; // Hit end of input without an error?
+ char scratch_[5]; // Temporary buffer for PeekFast() boundaries
+
+ // Ensure that all of the tag metadata for the next tag is available
+ // in [ip_..ip_limit_-1]. Also ensures that [ip,ip+4] is readable even
+ // if (ip_limit_ - ip_ < 5).
+ //
+ // Returns true on success, false on error or end of input.
+ bool RefillTag();
+
+ public:
+ explicit SnappyDecompressor(Source* reader)
+ : reader_(reader),
+ ip_(NULL),
+ ip_limit_(NULL),
+ peeked_(0),
+ eof_(false) {
+ }
+
+ ~SnappyDecompressor() {
+ // Advance past any bytes we peeked at from the reader
+ reader_->Skip(peeked_);
+ }
+
+ // Returns true iff we have hit the end of the input without an error.
+ bool eof() const {
+ return eof_;
+ }
+
+ // Read the uncompressed length stored at the start of the compressed data.
+ // On succcess, stores the length in *result and returns true.
+ // On failure, returns false.
+ bool ReadUncompressedLength(uint32* result) {
+ assert(ip_ == NULL); // Must not have read anything yet
+ // Length is encoded in 1..5 bytes
+ *result = 0;
+ uint32 shift = 0;
+ while (true) {
+ if (shift >= 32) return false;
+ size_t n;
+ const char* ip = reader_->Peek(&n);
+ if (n == 0) return false;
+ const unsigned char c = *(reinterpret_cast<const unsigned char*>(ip));
+ reader_->Skip(1);
+ *result |= static_cast<uint32>(c & 0x7f) << shift;
+ if (c < 128) {
+ break;
+ }
+ shift += 7;
+ }
+ return true;
+ }
+
+ // Process the next item found in the input.
+ // Returns true if successful, false on error or end of input.
+ template <class Writer>
+ void DecompressAllTags(Writer* writer) {
+ const char* ip = ip_;
+
+ // We could have put this refill fragment only at the beginning of the loop.
+ // However, duplicating it at the end of each branch gives the compiler more
+ // scope to optimize the <ip_limit_ - ip> expression based on the local
+ // context, which overall increases speed.
+ #define MAYBE_REFILL() \
+ if (ip_limit_ - ip < 5) { \
+ ip_ = ip; \
+ if (!RefillTag()) return; \
+ ip = ip_; \
+ }
+
+ MAYBE_REFILL();
+ for ( ;; ) {
+ const unsigned char c = *(reinterpret_cast<const unsigned char*>(ip++));
+
+ if ((c & 0x3) == LITERAL) {
+ size_t literal_length = (c >> 2) + 1u;
+ if (writer->TryFastAppend(ip, ip_limit_ - ip, literal_length)) {
+ assert(literal_length < 61);
+ ip += literal_length;
+ MAYBE_REFILL();
+ continue;
+ }
+ if (PREDICT_FALSE(literal_length >= 61)) {
+ // Long literal.
+ const size_t literal_length_length = literal_length - 60;
+ literal_length =
+ (LittleEndian::Load32(ip) & wordmask[literal_length_length]) + 1;
+ ip += literal_length_length;
+ }
+
+ size_t avail = ip_limit_ - ip;
+ while (avail < literal_length) {
+ if (!writer->Append(ip, avail)) return;
+ literal_length -= avail;
+ reader_->Skip(peeked_);
+ size_t n;
+ ip = reader_->Peek(&n);
+ avail = n;
+ peeked_ = avail;
+ if (avail == 0) return; // Premature end of input
+ ip_limit_ = ip + avail;
+ }
+ if (!writer->Append(ip, literal_length)) {
+ return;
+ }
+ ip += literal_length;
+ MAYBE_REFILL();
+ } else {
+ const uint32 entry = char_table[c];
+ const uint32 trailer = LittleEndian::Load32(ip) & wordmask[entry >> 11];
+ const uint32 length = entry & 0xff;
+ ip += entry >> 11;
+
+ // copy_offset/256 is encoded in bits 8..10. By just fetching
+ // those bits, we get copy_offset (since the bit-field starts at
+ // bit 8).
+ const uint32 copy_offset = entry & 0x700;
+ if (!writer->AppendFromSelf(copy_offset + trailer, length)) {
+ return;
+ }
+ MAYBE_REFILL();
+ }
+ }
+
+#undef MAYBE_REFILL
+ }
+};
+
+bool SnappyDecompressor::RefillTag() {
+ const char* ip = ip_;
+ if (ip == ip_limit_) {
+ // Fetch a new fragment from the reader
+ reader_->Skip(peeked_); // All peeked bytes are used up
+ size_t n;
+ ip = reader_->Peek(&n);
+ peeked_ = n;
+ if (n == 0) {
+ eof_ = true;
+ return false;
+ }
+ ip_limit_ = ip + n;
+ }
+
+ // Read the tag character
+ assert(ip < ip_limit_);
+ const unsigned char c = *(reinterpret_cast<const unsigned char*>(ip));
+ const uint32 entry = char_table[c];
+ const uint32 needed = (entry >> 11) + 1; // +1 byte for 'c'
+ assert(needed <= sizeof(scratch_));
+
+ // Read more bytes from reader if needed
+ uint32 nbuf = ip_limit_ - ip;
+ if (nbuf < needed) {
+ // Stitch together bytes from ip and reader to form the word
+ // contents. We store the needed bytes in "scratch_". They
+ // will be consumed immediately by the caller since we do not
+ // read more than we need.
+ memmove(scratch_, ip, nbuf);
+ reader_->Skip(peeked_); // All peeked bytes are used up
+ peeked_ = 0;
+ while (nbuf < needed) {
+ size_t length;
+ const char* src = reader_->Peek(&length);
+ if (length == 0) return false;
+ uint32 to_add = min<uint32>(needed - nbuf, length);
+ memcpy(scratch_ + nbuf, src, to_add);
+ nbuf += to_add;
+ reader_->Skip(to_add);
+ }
+ assert(nbuf == needed);
+ ip_ = scratch_;
+ ip_limit_ = scratch_ + needed;
+ } else if (nbuf < 5) {
+ // Have enough bytes, but move into scratch_ so that we do not
+ // read past end of input
+ memmove(scratch_, ip, nbuf);
+ reader_->Skip(peeked_); // All peeked bytes are used up
+ peeked_ = 0;
+ ip_ = scratch_;
+ ip_limit_ = scratch_ + nbuf;
+ } else {
+ // Pass pointer to buffer returned by reader_.
+ ip_ = ip;
+ }
+ return true;
+}
+
+template <typename Writer>
+static bool InternalUncompress(Source* r,
+ Writer* writer,
+ uint32 max_len) {
+ // Read the uncompressed length from the front of the compressed input
+ SnappyDecompressor decompressor(r);
+ uint32 uncompressed_len = 0;
+ if (!decompressor.ReadUncompressedLength(&uncompressed_len)) return false;
+ return InternalUncompressAllTags(
+ &decompressor, writer, uncompressed_len, max_len);
+}
+
+template <typename Writer>
+static bool InternalUncompressAllTags(SnappyDecompressor* decompressor,
+ Writer* writer,
+ uint32 uncompressed_len,
+ uint32 max_len) {
+ // Protect against possible DoS attack
+ if (static_cast<uint64>(uncompressed_len) > max_len) {
+ return false;
+ }
+
+ writer->SetExpectedLength(uncompressed_len);
+
+ // Process the entire input
+ decompressor->DecompressAllTags(writer);
+ return (decompressor->eof() && writer->CheckLength());
+}
+
+bool GetUncompressedLength(Source* source, uint32* result) {
+ SnappyDecompressor decompressor(source);
+ return decompressor.ReadUncompressedLength(result);
+}
+
+size_t Compress(Source* reader, Sink* writer) {
+ size_t written = 0;
+ size_t N = reader->Available();
+ char ulength[Varint::kMax32];
+ char* p = Varint::Encode32(ulength, N);
+ writer->Append(ulength, p-ulength);
+ written += (p - ulength);
+
+ internal::WorkingMemory wmem;
+ char* scratch = NULL;
+ char* scratch_output = NULL;
+
+ while (N > 0) {
+ // Get next block to compress (without copying if possible)
+ size_t fragment_size;
+ const char* fragment = reader->Peek(&fragment_size);
+ assert(fragment_size != 0); // premature end of input
+ const size_t num_to_read = min(N, kBlockSize);
+ size_t bytes_read = fragment_size;
+
+ size_t pending_advance = 0;
+ if (bytes_read >= num_to_read) {
+ // Buffer returned by reader is large enough
+ pending_advance = num_to_read;
+ fragment_size = num_to_read;
+ } else {
+ // Read into scratch buffer
+ if (scratch == NULL) {
+ // If this is the last iteration, we want to allocate N bytes
+ // of space, otherwise the max possible kBlockSize space.
+ // num_to_read contains exactly the correct value
+ scratch = new char[num_to_read];
+ }
+ memcpy(scratch, fragment, bytes_read);
+ reader->Skip(bytes_read);
+
+ while (bytes_read < num_to_read) {
+ fragment = reader->Peek(&fragment_size);
+ size_t n = min<size_t>(fragment_size, num_to_read - bytes_read);
+ memcpy(scratch + bytes_read, fragment, n);
+ bytes_read += n;
+ reader->Skip(n);
+ }
+ assert(bytes_read == num_to_read);
+ fragment = scratch;
+ fragment_size = num_to_read;
+ }
+ assert(fragment_size == num_to_read);
+
+ // Get encoding table for compression
+ int table_size;
+ uint16* table = wmem.GetHashTable(num_to_read, &table_size);
+
+ // Compress input_fragment and append to dest
+ const int max_output = MaxCompressedLength(num_to_read);
+
+ // Need a scratch buffer for the output, in case the byte sink doesn't
+ // have room for us directly.
+ if (scratch_output == NULL) {
+ scratch_output = new char[max_output];
+ } else {
+ // Since we encode kBlockSize regions followed by a region
+ // which is <= kBlockSize in length, a previously allocated
+ // scratch_output[] region is big enough for this iteration.
+ }
+ char* dest = writer->GetAppendBuffer(max_output, scratch_output);
+ char* end = internal::CompressFragment(fragment, fragment_size,
+ dest, table, table_size);
+ writer->Append(dest, end - dest);
+ written += (end - dest);
+
+ N -= num_to_read;
+ reader->Skip(pending_advance);
+ }
+
+ delete[] scratch;
+ delete[] scratch_output;
+
+ return written;
+}
+
+// -----------------------------------------------------------------------
+// Flat array interfaces
+// -----------------------------------------------------------------------
+
+// A type that writes to a flat array.
+// Note that this is not a "ByteSink", but a type that matches the
+// Writer template argument to SnappyDecompressor::DecompressAllTags().
+class SnappyArrayWriter {
+ private:
+ char* base_;
+ char* op_;
+ char* op_limit_;
+
+ public:
+ inline explicit SnappyArrayWriter(char* dst)
+ : base_(dst),
+ op_(dst) {
+ }
+
+ inline void SetExpectedLength(size_t len) {
+ op_limit_ = op_ + len;
+ }
+
+ inline bool CheckLength() const {
+ return op_ == op_limit_;
+ }
+
+ inline bool Append(const char* ip, size_t len) {
+ char* op = op_;
+ const size_t space_left = op_limit_ - op;
+ if (space_left < len) {
+ return false;
+ }
+ memcpy(op, ip, len);
+ op_ = op + len;
+ return true;
+ }
+
+ inline bool TryFastAppend(const char* ip, size_t available, size_t len) {
+ char* op = op_;
+ const size_t space_left = op_limit_ - op;
+ if (len <= 16 && available >= 16 && space_left >= 16) {
+ // Fast path, used for the majority (about 95%) of invocations.
+ UnalignedCopy64(ip, op);
+ UnalignedCopy64(ip + 8, op + 8);
+ op_ = op + len;
+ return true;
+ } else {
+ return false;
+ }
+ }
+
+ inline bool AppendFromSelf(size_t offset, size_t len) {
+ char* op = op_;
+ const size_t space_left = op_limit_ - op;
+
+ if (op - base_ <= offset - 1u) { // -1u catches offset==0
+ return false;
+ }
+ if (len <= 16 && offset >= 8 && space_left >= 16) {
+ // Fast path, used for the majority (70-80%) of dynamic invocations.
+ UnalignedCopy64(op - offset, op);
+ UnalignedCopy64(op - offset + 8, op + 8);
+ } else {
+ if (space_left >= len + kMaxIncrementCopyOverflow) {
+ IncrementalCopyFastPath(op - offset, op, len);
+ } else {
+ if (space_left < len) {
+ return false;
+ }
+ IncrementalCopy(op - offset, op, len);
+ }
+ }
+
+ op_ = op + len;
+ return true;
+ }
+};
+
+bool RawUncompress(const char* compressed, size_t n, char* uncompressed) {
+ ByteArraySource reader(compressed, n);
+ return RawUncompress(&reader, uncompressed);
+}
+
+bool RawUncompress(Source* compressed, char* uncompressed) {
+ SnappyArrayWriter output(uncompressed);
+ return InternalUncompress(compressed, &output, kuint32max);
+}
+
+bool Uncompress(const char* compressed, size_t n, string* uncompressed) {
+ size_t ulength;
+ if (!GetUncompressedLength(compressed, n, &ulength)) {
+ return false;
+ }
+ // Protect against possible DoS attack
+ if ((static_cast<uint64>(ulength) + uncompressed->size()) >
+ uncompressed->max_size()) {
+ return false;
+ }
+ STLStringResizeUninitialized(uncompressed, ulength);
+ return RawUncompress(compressed, n, string_as_array(uncompressed));
+}
+
+
+// A Writer that drops everything on the floor and just does validation
+class SnappyDecompressionValidator {
+ private:
+ size_t expected_;
+ size_t produced_;
+
+ public:
+ inline SnappyDecompressionValidator() : produced_(0) { }
+ inline void SetExpectedLength(size_t len) {
+ expected_ = len;
+ }
+ inline bool CheckLength() const {
+ return expected_ == produced_;
+ }
+ inline bool Append(const char* ip, size_t len) {
+ produced_ += len;
+ return produced_ <= expected_;
+ }
+ inline bool TryFastAppend(const char* ip, size_t available, size_t length) {
+ return false;
+ }
+ inline bool AppendFromSelf(size_t offset, size_t len) {
+ if (produced_ <= offset - 1u) return false; // -1u catches offset==0
+ produced_ += len;
+ return produced_ <= expected_;
+ }
+};
+
+bool IsValidCompressedBuffer(const char* compressed, size_t n) {
+ ByteArraySource reader(compressed, n);
+ SnappyDecompressionValidator writer;
+ return InternalUncompress(&reader, &writer, kuint32max);
+}
+
+void RawCompress(const char* input,
+ size_t input_length,
+ char* compressed,
+ size_t* compressed_length) {
+ ByteArraySource reader(input, input_length);
+ UncheckedByteArraySink writer(compressed);
+ Compress(&reader, &writer);
+
+ // Compute how many bytes were added
+ *compressed_length = (writer.CurrentDestination() - compressed);
+}
+
+size_t Compress(const char* input, size_t input_length, string* compressed) {
+ // Pre-grow the buffer to the max length of the compressed output
+ compressed->resize(MaxCompressedLength(input_length));
+
+ size_t compressed_length;
+ RawCompress(input, input_length, string_as_array(compressed),
+ &compressed_length);
+ compressed->resize(compressed_length);
+ return compressed_length;
+}
+
+
+} // end namespace snappy
+
diff --git a/app/snappy/snappy.h b/app/snappy/snappy.h
new file mode 100644
index 00000000..03ef6ce5
--- /dev/null
+++ b/app/snappy/snappy.h
@@ -0,0 +1,163 @@
+// Copyright 2005 and onwards Google Inc.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+// A light-weight compression algorithm. It is designed for speed of
+// compression and decompression, rather than for the utmost in space
+// savings.
+//
+// For getting better compression ratios when you are compressing data
+// with long repeated sequences or compressing data that is similar to
+// other data, while still compressing fast, you might look at first
+// using BMDiff and then compressing the output of BMDiff with
+// Snappy.
+
+#ifndef UTIL_SNAPPY_SNAPPY_H__
+#define UTIL_SNAPPY_SNAPPY_H__
+
+#include <stddef.h>
+#include <string>
+
+#include "snappy-stubs-public.h"
+
+namespace snappy {
+ class Source;
+ class Sink;
+
+ // ------------------------------------------------------------------------
+ // Generic compression/decompression routines.
+ // ------------------------------------------------------------------------
+
+ // Compress the bytes read from "*source" and append to "*sink". Return the
+ // number of bytes written.
+ size_t Compress(Source* source, Sink* sink);
+
+ // Find the uncompressed length of the given stream, as given by the header.
+ // Note that the true length could deviate from this; the stream could e.g.
+ // be truncated.
+ //
+ // Also note that this leaves "*source" in a state that is unsuitable for
+ // further operations, such as RawUncompress(). You will need to rewind
+ // or recreate the source yourself before attempting any further calls.
+ bool GetUncompressedLength(Source* source, uint32* result);
+
+ // ------------------------------------------------------------------------
+ // Higher-level string based routines (should be sufficient for most users)
+ // ------------------------------------------------------------------------
+
+ // Sets "*output" to the compressed version of "input[0,input_length-1]".
+ // Original contents of *output are lost.
+ //
+ // REQUIRES: "input[]" is not an alias of "*output".
+ size_t Compress(const char* input, size_t input_length, string* output);
+
+ // Decompresses "compressed[0,compressed_length-1]" to "*uncompressed".
+ // Original contents of "*uncompressed" are lost.
+ //
+ // REQUIRES: "compressed[]" is not an alias of "*uncompressed".
+ //
+ // returns false if the message is corrupted and could not be decompressed
+ bool Uncompress(const char* compressed, size_t compressed_length,
+ string* uncompressed);
+
+
+ // ------------------------------------------------------------------------
+ // Lower-level character array based routines. May be useful for
+ // efficiency reasons in certain circumstances.
+ // ------------------------------------------------------------------------
+
+ // REQUIRES: "compressed" must point to an area of memory that is at
+ // least "MaxCompressedLength(input_length)" bytes in length.
+ //
+ // Takes the data stored in "input[0..input_length]" and stores
+ // it in the array pointed to by "compressed".
+ //
+ // "*compressed_length" is set to the length of the compressed output.
+ //
+ // Example:
+ // char* output = new char[snappy::MaxCompressedLength(input_length)];
+ // size_t output_length;
+ // RawCompress(input, input_length, output, &output_length);
+ // ... Process(output, output_length) ...
+ // delete [] output;
+ void RawCompress(const char* input,
+ size_t input_length,
+ char* compressed,
+ size_t* compressed_length);
+
+ // Given data in "compressed[0..compressed_length-1]" generated by
+ // calling the Snappy::Compress routine, this routine
+ // stores the uncompressed data to
+ // uncompressed[0..GetUncompressedLength(compressed)-1]
+ // returns false if the message is corrupted and could not be decrypted
+ bool RawUncompress(const char* compressed, size_t compressed_length,
+ char* uncompressed);
+
+ // Given data from the byte source 'compressed' generated by calling
+ // the Snappy::Compress routine, this routine stores the uncompressed
+ // data to
+ // uncompressed[0..GetUncompressedLength(compressed,compressed_length)-1]
+ // returns false if the message is corrupted and could not be decrypted
+ bool RawUncompress(Source* compressed, char* uncompressed);
+
+ // Returns the maximal size of the compressed representation of
+ // input data that is "source_bytes" bytes in length;
+ size_t MaxCompressedLength(size_t source_bytes);
+
+ // REQUIRES: "compressed[]" was produced by RawCompress() or Compress()
+ // Returns true and stores the length of the uncompressed data in
+ // *result normally. Returns false on parsing error.
+ // This operation takes O(1) time.
+ bool GetUncompressedLength(const char* compressed, size_t compressed_length,
+ size_t* result);
+
+ // Returns true iff the contents of "compressed[]" can be uncompressed
+ // successfully. Does not return the uncompressed data. Takes
+ // time proportional to compressed_length, but is usually at least
+ // a factor of four faster than actual decompression.
+ bool IsValidCompressedBuffer(const char* compressed,
+ size_t compressed_length);
+
+ // The size of a compression block. Note that many parts of the compression
+ // code assumes that kBlockSize <= 65536; in particular, the hash table
+ // can only store 16-bit offsets, and EmitCopy() also assumes the offset
+ // is 65535 bytes or less. Note also that if you change this, it will
+ // affect the framing format (see framing_format.txt).
+ //
+ // Note that there might be older data around that is compressed with larger
+ // block sizes, so the decompression code should not rely on the
+ // non-existence of long backreferences.
+ static const int kBlockLog = 16;
+ static const size_t kBlockSize = 1 << kBlockLog;
+
+ static const int kMaxHashTableBits = 14;
+ static const size_t kMaxHashTableSize = 1 << kMaxHashTableBits;
+
+} // end namespace snappy
+
+
+#endif // UTIL_SNAPPY_SNAPPY_H__
diff --git a/app/snappy/snappy_unittest.cc b/app/snappy/snappy_unittest.cc
new file mode 100644
index 00000000..59c108f4
--- /dev/null
+++ b/app/snappy/snappy_unittest.cc
@@ -0,0 +1,1164 @@
+// Copyright 2005 and onwards Google Inc.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+// * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include <math.h>
+#include <stdlib.h>
+
+
+#include <algorithm>
+#include <string>
+#include <vector>
+
+#include "snappy.h"
+#include "snappy-internal.h"
+#include "snappy-test.h"
+#include "snappy-sinksource.h"
+
+DEFINE_int32(start_len, -1,
+ "Starting prefix size for testing (-1: just full file contents)");
+DEFINE_int32(end_len, -1,
+ "Starting prefix size for testing (-1: just full file contents)");
+DEFINE_int32(bytes, 10485760,
+ "How many bytes to compress/uncompress per file for timing");
+
+DEFINE_bool(zlib, false,
+ "Run zlib compression (http://www.zlib.net)");
+DEFINE_bool(lzo, false,
+ "Run LZO compression (http://www.oberhumer.com/opensource/lzo/)");
+DEFINE_bool(quicklz, false,
+ "Run quickLZ compression (http://www.quicklz.com/)");
+DEFINE_bool(liblzf, false,
+ "Run libLZF compression "
+ "(http://www.goof.com/pcg/marc/liblzf.html)");
+DEFINE_bool(fastlz, false,
+ "Run FastLZ compression (http://www.fastlz.org/");
+DEFINE_bool(snappy, true, "Run snappy compression");
+
+
+DEFINE_bool(write_compressed, false,
+ "Write compressed versions of each file to <file>.comp");
+DEFINE_bool(write_uncompressed, false,
+ "Write uncompressed versions of each file to <file>.uncomp");
+
+namespace snappy {
+
+
+#ifdef HAVE_FUNC_MMAP
+
+// To test against code that reads beyond its input, this class copies a
+// string to a newly allocated group of pages, the last of which
+// is made unreadable via mprotect. Note that we need to allocate the
+// memory with mmap(), as POSIX allows mprotect() only on memory allocated
+// with mmap(), and some malloc/posix_memalign implementations expect to
+// be able to read previously allocated memory while doing heap allocations.
+class DataEndingAtUnreadablePage {
+ public:
+ explicit DataEndingAtUnreadablePage(const string& s) {
+ const size_t page_size = getpagesize();
+ const size_t size = s.size();
+ // Round up space for string to a multiple of page_size.
+ size_t space_for_string = (size + page_size - 1) & ~(page_size - 1);
+ alloc_size_ = space_for_string + page_size;
+ mem_ = mmap(NULL, alloc_size_,
+ PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
+ CHECK_NE(MAP_FAILED, mem_);
+ protected_page_ = reinterpret_cast<char*>(mem_) + space_for_string;
+ char* dst = protected_page_ - size;
+ memcpy(dst, s.data(), size);
+ data_ = dst;
+ size_ = size;
+ // Make guard page unreadable.
+ CHECK_EQ(0, mprotect(protected_page_, page_size, PROT_NONE));
+ }
+
+ ~DataEndingAtUnreadablePage() {
+ // Undo the mprotect.
+ CHECK_EQ(0, mprotect(protected_page_, getpagesize(), PROT_READ|PROT_WRITE));
+ CHECK_EQ(0, munmap(mem_, alloc_size_));
+ }
+
+ const char* data() const { return data_; }
+ size_t size() const { return size_; }
+
+ private:
+ size_t alloc_size_;
+ void* mem_;
+ char* protected_page_;
+ const char* data_;
+ size_t size_;
+};
+
+#else // HAVE_FUNC_MMAP
+
+// Fallback for systems without mmap.
+typedef string DataEndingAtUnreadablePage;
+
+#endif
+
+enum CompressorType {
+ ZLIB, LZO, LIBLZF, QUICKLZ, FASTLZ, SNAPPY
+};
+
+const char* names[] = {
+ "ZLIB", "LZO", "LIBLZF", "QUICKLZ", "FASTLZ", "SNAPPY"
+};
+
+static size_t MinimumRequiredOutputSpace(size_t input_size,
+ CompressorType comp) {
+ switch (comp) {
+#ifdef ZLIB_VERSION
+ case ZLIB:
+ return ZLib::MinCompressbufSize(input_size);
+#endif // ZLIB_VERSION
+
+#ifdef LZO_VERSION
+ case LZO:
+ return input_size + input_size/64 + 16 + 3;
+#endif // LZO_VERSION
+
+#ifdef LZF_VERSION
+ case LIBLZF:
+ return input_size;
+#endif // LZF_VERSION
+
+#ifdef QLZ_VERSION_MAJOR
+ case QUICKLZ:
+ return input_size + 36000; // 36000 is used for scratch.
+#endif // QLZ_VERSION_MAJOR
+
+#ifdef FASTLZ_VERSION
+ case FASTLZ:
+ return max(static_cast<int>(ceil(input_size * 1.05)), 66);
+#endif // FASTLZ_VERSION
+
+ case SNAPPY:
+ return snappy::MaxCompressedLength(input_size);
+
+ default:
+ LOG(FATAL) << "Unknown compression type number " << comp;
+ }
+}
+
+// Returns true if we successfully compressed, false otherwise.
+//
+// If compressed_is_preallocated is set, do not resize the compressed buffer.
+// This is typically what you want for a benchmark, in order to not spend
+// time in the memory allocator. If you do set this flag, however,
+// "compressed" must be preinitialized to at least MinCompressbufSize(comp)
+// number of bytes, and may contain junk bytes at the end after return.
+static bool Compress(const char* input, size_t input_size, CompressorType comp,
+ string* compressed, bool compressed_is_preallocated) {
+ if (!compressed_is_preallocated) {
+ compressed->resize(MinimumRequiredOutputSpace(input_size, comp));
+ }
+
+ switch (comp) {
+#ifdef ZLIB_VERSION
+ case ZLIB: {
+ ZLib zlib;
+ uLongf destlen = compressed->size();
+ int ret = zlib.Compress(
+ reinterpret_cast<Bytef*>(string_as_array(compressed)),
+ &destlen,
+ reinterpret_cast<const Bytef*>(input),
+ input_size);
+ CHECK_EQ(Z_OK, ret);
+ if (!compressed_is_preallocated) {
+ compressed->resize(destlen);
+ }
+ return true;
+ }
+#endif // ZLIB_VERSION
+
+#ifdef LZO_VERSION
+ case LZO: {
+ unsigned char* mem = new unsigned char[LZO1X_1_15_MEM_COMPRESS];
+ lzo_uint destlen;
+ int ret = lzo1x_1_15_compress(
+ reinterpret_cast<const uint8*>(input),
+ input_size,
+ reinterpret_cast<uint8*>(string_as_array(compressed)),
+ &destlen,
+ mem);
+ CHECK_EQ(LZO_E_OK, ret);
+ delete[] mem;
+ if (!compressed_is_preallocated) {
+ compressed->resize(destlen);
+ }
+ break;
+ }
+#endif // LZO_VERSION
+
+#ifdef LZF_VERSION
+ case LIBLZF: {
+ int destlen = lzf_compress(input,
+ input_size,
+ string_as_array(compressed),
+ input_size);
+ if (destlen == 0) {
+ // lzf *can* cause lots of blowup when compressing, so they
+ // recommend to limit outsize to insize, and just not compress
+ // if it's bigger. Ideally, we'd just swap input and output.
+ compressed->assign(input, input_size);
+ destlen = input_size;
+ }
+ if (!compressed_is_preallocated) {
+ compressed->resize(destlen);
+ }
+ break;
+ }
+#endif // LZF_VERSION
+
+#ifdef QLZ_VERSION_MAJOR
+ case QUICKLZ: {
+ qlz_state_compress *state_compress = new qlz_state_compress;
+ int destlen = qlz_compress(input,
+ string_as_array(compressed),
+ input_size,
+ state_compress);
+ delete state_compress;
+ CHECK_NE(0, destlen);
+ if (!compressed_is_preallocated) {
+ compressed->resize(destlen);
+ }
+ break;
+ }
+#endif // QLZ_VERSION_MAJOR
+
+#ifdef FASTLZ_VERSION
+ case FASTLZ: {
+ // Use level 1 compression since we mostly care about speed.
+ int destlen = fastlz_compress_level(
+ 1,
+ input,
+ input_size,
+ string_as_array(compressed));
+ if (!compressed_is_preallocated) {
+ compressed->resize(destlen);
+ }
+ CHECK_NE(destlen, 0);
+ break;
+ }
+#endif // FASTLZ_VERSION
+
+ case SNAPPY: {
+ size_t destlen;
+ snappy::RawCompress(input, input_size,
+ string_as_array(compressed),
+ &destlen);
+ CHECK_LE(destlen, snappy::MaxCompressedLength(input_size));
+ if (!compressed_is_preallocated) {
+ compressed->resize(destlen);
+ }
+ break;
+ }
+
+
+ default: {
+ return false; // the asked-for library wasn't compiled in
+ }
+ }
+ return true;
+}
+
+static bool Uncompress(const string& compressed, CompressorType comp,
+ int size, string* output) {
+ switch (comp) {
+#ifdef ZLIB_VERSION
+ case ZLIB: {
+ output->resize(size);
+ ZLib zlib;
+ uLongf destlen = output->size();
+ int ret = zlib.Uncompress(
+ reinterpret_cast<Bytef*>(string_as_array(output)),
+ &destlen,
+ reinterpret_cast<const Bytef*>(compressed.data()),
+ compressed.size());
+ CHECK_EQ(Z_OK, ret);
+ CHECK_EQ(static_cast<uLongf>(size), destlen);
+ break;
+ }
+#endif // ZLIB_VERSION
+
+#ifdef LZO_VERSION
+ case LZO: {
+ output->resize(size);
+ lzo_uint destlen;
+ int ret = lzo1x_decompress(
+ reinterpret_cast<const uint8*>(compressed.data()),
+ compressed.size(),
+ reinterpret_cast<uint8*>(string_as_array(output)),
+ &destlen,
+ NULL);
+ CHECK_EQ(LZO_E_OK, ret);
+ CHECK_EQ(static_cast<lzo_uint>(size), destlen);
+ break;
+ }
+#endif // LZO_VERSION
+
+#ifdef LZF_VERSION
+ case LIBLZF: {
+ output->resize(size);
+ int destlen = lzf_decompress(compressed.data(),
+ compressed.size(),
+ string_as_array(output),
+ output->size());
+ if (destlen == 0) {
+ // This error probably means we had decided not to compress,
+ // and thus have stored input in output directly.
+ output->assign(compressed.data(), compressed.size());
+ destlen = compressed.size();
+ }
+ CHECK_EQ(destlen, size);
+ break;
+ }
+#endif // LZF_VERSION
+
+#ifdef QLZ_VERSION_MAJOR
+ case QUICKLZ: {
+ output->resize(size);
+ qlz_state_decompress *state_decompress = new qlz_state_decompress;
+ int destlen = qlz_decompress(compressed.data(),
+ string_as_array(output),
+ state_decompress);
+ delete state_decompress;
+ CHECK_EQ(destlen, size);
+ break;
+ }
+#endif // QLZ_VERSION_MAJOR
+
+#ifdef FASTLZ_VERSION
+ case FASTLZ: {
+ output->resize(size);
+ int destlen = fastlz_decompress(compressed.data(),
+ compressed.length(),
+ string_as_array(output),
+ size);
+ CHECK_EQ(destlen, size);
+ break;
+ }
+#endif // FASTLZ_VERSION
+
+ case SNAPPY: {
+ snappy::RawUncompress(compressed.data(), compressed.size(),
+ string_as_array(output));
+ break;
+ }
+
+
+ default: {
+ return false; // the asked-for library wasn't compiled in
+ }
+ }
+ return true;
+}
+
+static void Measure(const char* data,
+ size_t length,
+ CompressorType comp,
+ int repeats,
+ int block_size) {
+ // Run tests a few time and pick median running times
+ static const int kRuns = 5;
+ double ctime[kRuns];
+ double utime[kRuns];
+ int compressed_size = 0;
+
+ {
+ // Chop the input into blocks
+ int num_blocks = (length + block_size - 1) / block_size;
+ vector<const char*> input(num_blocks);
+ vector<size_t> input_length(num_blocks);
+ vector<string> compressed(num_blocks);
+ vector<string> output(num_blocks);
+ for (int b = 0; b < num_blocks; b++) {
+ int input_start = b * block_size;
+ int input_limit = min<int>((b+1)*block_size, length);
+ input[b] = data+input_start;
+ input_length[b] = input_limit-input_start;
+
+ // Pre-grow the output buffer so we don't measure string append time.
+ compressed[b].resize(MinimumRequiredOutputSpace(block_size, comp));
+ }
+
+ // First, try one trial compression to make sure the code is compiled in
+ if (!Compress(input[0], input_length[0], comp, &compressed[0], true)) {
+ LOG(WARNING) << "Skipping " << names[comp] << ": "
+ << "library not compiled in";
+ return;
+ }
+
+ for (int run = 0; run < kRuns; run++) {
+ CycleTimer ctimer, utimer;
+
+ for (int b = 0; b < num_blocks; b++) {
+ // Pre-grow the output buffer so we don't measure string append time.
+ compressed[b].resize(MinimumRequiredOutputSpace(block_size, comp));
+ }
+
+ ctimer.Start();
+ for (int b = 0; b < num_blocks; b++)
+ for (int i = 0; i < repeats; i++)
+ Compress(input[b], input_length[b], comp, &compressed[b], true);
+ ctimer.Stop();
+
+ // Compress once more, with resizing, so we don't leave junk
+ // at the end that will confuse the decompressor.
+ for (int b = 0; b < num_blocks; b++) {
+ Compress(input[b], input_length[b], comp, &compressed[b], false);
+ }
+
+ for (int b = 0; b < num_blocks; b++) {
+ output[b].resize(input_length[b]);
+ }
+
+ utimer.Start();
+ for (int i = 0; i < repeats; i++)
+ for (int b = 0; b < num_blocks; b++)
+ Uncompress(compressed[b], comp, input_length[b], &output[b]);
+ utimer.Stop();
+
+ ctime[run] = ctimer.Get();
+ utime[run] = utimer.Get();
+ }
+
+ compressed_size = 0;
+ for (int i = 0; i < compressed.size(); i++) {
+ compressed_size += compressed[i].size();
+ }
+ }
+
+ sort(ctime, ctime + kRuns);
+ sort(utime, utime + kRuns);
+ const int med = kRuns/2;
+
+ float comp_rate = (length / ctime[med]) * repeats / 1048576.0;
+ float uncomp_rate = (length / utime[med]) * repeats / 1048576.0;
+ string x = names[comp];
+ x += ":";
+ string urate = (uncomp_rate >= 0)
+ ? StringPrintf("%.1f", uncomp_rate)
+ : string("?");
+ printf("%-7s [b %dM] bytes %6d -> %6d %4.1f%% "
+ "comp %5.1f MB/s uncomp %5s MB/s\n",
+ x.c_str(),
+ block_size/(1<<20),
+ static_cast<int>(length), static_cast<uint32>(compressed_size),
+ (compressed_size * 100.0) / max<int>(1, length),
+ comp_rate,
+ urate.c_str());
+}
+
+
+static int VerifyString(const string& input) {
+ string compressed;
+ DataEndingAtUnreadablePage i(input);
+ const size_t written = snappy::Compress(i.data(), i.size(), &compressed);
+ CHECK_EQ(written, compressed.size());
+ CHECK_LE(compressed.size(),
+ snappy::MaxCompressedLength(input.size()));
+ CHECK(snappy::IsValidCompressedBuffer(compressed.data(), compressed.size()));
+
+ string uncompressed;
+ DataEndingAtUnreadablePage c(compressed);
+ CHECK(snappy::Uncompress(c.data(), c.size(), &uncompressed));
+ CHECK_EQ(uncompressed, input);
+ return uncompressed.size();
+}
+
+
+// Test that data compressed by a compressor that does not
+// obey block sizes is uncompressed properly.
+static void VerifyNonBlockedCompression(const string& input) {
+ if (input.length() > snappy::kBlockSize) {
+ // We cannot test larger blocks than the maximum block size, obviously.
+ return;
+ }
+
+ string prefix;
+ Varint::Append32(&prefix, input.size());
+
+ // Setup compression table
+ snappy::internal::WorkingMemory wmem;
+ int table_size;
+ uint16* table = wmem.GetHashTable(input.size(), &table_size);
+
+ // Compress entire input in one shot
+ string compressed;
+ compressed += prefix;
+ compressed.resize(prefix.size()+snappy::MaxCompressedLength(input.size()));
+ char* dest = string_as_array(&compressed) + prefix.size();
+ char* end = snappy::internal::CompressFragment(input.data(), input.size(),
+ dest, table, table_size);
+ compressed.resize(end - compressed.data());
+
+ // Uncompress into string
+ string uncomp_str;
+ CHECK(snappy::Uncompress(compressed.data(), compressed.size(), &uncomp_str));
+ CHECK_EQ(uncomp_str, input);
+
+}
+
+// Expand the input so that it is at least K times as big as block size
+static string Expand(const string& input) {
+ static const int K = 3;
+ string data = input;
+ while (data.size() < K * snappy::kBlockSize) {
+ data += input;
+ }
+ return data;
+}
+
+static int Verify(const string& input) {
+ VLOG(1) << "Verifying input of size " << input.size();
+
+ // Compress using string based routines
+ const int result = VerifyString(input);
+
+
+ VerifyNonBlockedCompression(input);
+ if (!input.empty()) {
+ VerifyNonBlockedCompression(Expand(input));
+ }
+
+
+ return result;
+}
+
+// This test checks to ensure that snappy doesn't coredump if it gets
+// corrupted data.
+
+static bool IsValidCompressedBuffer(const string& c) {
+ return snappy::IsValidCompressedBuffer(c.data(), c.size());
+}
+static bool Uncompress(const string& c, string* u) {
+ return snappy::Uncompress(c.data(), c.size(), u);
+}
+
+TYPED_TEST(CorruptedTest, VerifyCorrupted) {
+ string source = "making sure we don't crash with corrupted input";
+ VLOG(1) << source;
+ string dest;
+ TypeParam uncmp;
+ snappy::Compress(source.data(), source.size(), &dest);
+
+ // Mess around with the data. It's hard to simulate all possible
+ // corruptions; this is just one example ...
+ CHECK_GT(dest.size(), 3);
+ dest[1]--;
+ dest[3]++;
+ // this really ought to fail.
+ CHECK(!IsValidCompressedBuffer(TypeParam(dest)));
+ CHECK(!Uncompress(TypeParam(dest), &uncmp));
+
+ // This is testing for a security bug - a buffer that decompresses to 100k
+ // but we lie in the snappy header and only reserve 0 bytes of memory :)
+ source.resize(100000);
+ for (int i = 0; i < source.length(); ++i) {
+ source[i] = 'A';
+ }
+ snappy::Compress(source.data(), source.size(), &dest);
+ dest[0] = dest[1] = dest[2] = dest[3] = 0;
+ CHECK(!IsValidCompressedBuffer(TypeParam(dest)));
+ CHECK(!Uncompress(TypeParam(dest), &uncmp));
+
+ if (sizeof(void *) == 4) {
+ // Another security check; check a crazy big length can't DoS us with an
+ // over-allocation.
+ // Currently this is done only for 32-bit builds. On 64-bit builds,
+ // where 3 GB might be an acceptable allocation size, Uncompress()
+ // attempts to decompress, and sometimes causes the test to run out of
+ // memory.
+ dest[0] = dest[1] = dest[2] = dest[3] = 0xff;
+ // This decodes to a really large size, i.e., about 3 GB.
+ dest[4] = 'k';
+ CHECK(!IsValidCompressedBuffer(TypeParam(dest)));
+ CHECK(!Uncompress(TypeParam(dest), &uncmp));
+ } else {
+ LOG(WARNING) << "Crazy decompression lengths not checked on 64-bit build";
+ }
+
+ // This decodes to about 2 MB; much smaller, but should still fail.
+ dest[0] = dest[1] = dest[2] = 0xff;
+ dest[3] = 0x00;
+ CHECK(!IsValidCompressedBuffer(TypeParam(dest)));
+ CHECK(!Uncompress(TypeParam(dest), &uncmp));
+
+ // try reading stuff in from a bad file.
+ for (int i = 1; i <= 3; ++i) {
+ string data = ReadTestDataFile(StringPrintf("baddata%d.snappy", i).c_str(),
+ 0);
+ string uncmp;
+ // check that we don't return a crazy length
+ size_t ulen;
+ CHECK(!snappy::GetUncompressedLength(data.data(), data.size(), &ulen)
+ || (ulen < (1<<20)));
+ uint32 ulen2;
+ snappy::ByteArraySource source(data.data(), data.size());
+ CHECK(!snappy::GetUncompressedLength(&source, &ulen2) ||
+ (ulen2 < (1<<20)));
+ CHECK(!IsValidCompressedBuffer(TypeParam(data)));
+ CHECK(!Uncompress(TypeParam(data), &uncmp));
+ }
+}
+
+// Helper routines to construct arbitrary compressed strings.
+// These mirror the compression code in snappy.cc, but are copied
+// here so that we can bypass some limitations in the how snappy.cc
+// invokes these routines.
+static void AppendLiteral(string* dst, const string& literal) {
+ if (literal.empty()) return;
+ int n = literal.size() - 1;
+ if (n < 60) {
+ // Fit length in tag byte
+ dst->push_back(0 | (n << 2));
+ } else {
+ // Encode in upcoming bytes
+ char number[4];
+ int count = 0;
+ while (n > 0) {
+ number[count++] = n & 0xff;
+ n >>= 8;
+ }
+ dst->push_back(0 | ((59+count) << 2));
+ *dst += string(number, count);
+ }
+ *dst += literal;
+}
+
+static void AppendCopy(string* dst, int offset, int length) {
+ while (length > 0) {
+ // Figure out how much to copy in one shot
+ int to_copy;
+ if (length >= 68) {
+ to_copy = 64;
+ } else if (length > 64) {
+ to_copy = 60;
+ } else {
+ to_copy = length;
+ }
+ length -= to_copy;
+
+ if ((to_copy < 12) && (offset < 2048)) {
+ assert(to_copy-4 < 8); // Must fit in 3 bits
+ dst->push_back(1 | ((to_copy-4) << 2) | ((offset >> 8) << 5));
+ dst->push_back(offset & 0xff);
+ } else if (offset < 65536) {
+ dst->push_back(2 | ((to_copy-1) << 2));
+ dst->push_back(offset & 0xff);
+ dst->push_back(offset >> 8);
+ } else {
+ dst->push_back(3 | ((to_copy-1) << 2));
+ dst->push_back(offset & 0xff);
+ dst->push_back((offset >> 8) & 0xff);
+ dst->push_back((offset >> 16) & 0xff);
+ dst->push_back((offset >> 24) & 0xff);
+ }
+ }
+}
+
+TEST(Snappy, SimpleTests) {
+ Verify("");
+ Verify("a");
+ Verify("ab");
+ Verify("abc");
+
+ Verify("aaaaaaa" + string(16, 'b') + string("aaaaa") + "abc");
+ Verify("aaaaaaa" + string(256, 'b') + string("aaaaa") + "abc");
+ Verify("aaaaaaa" + string(2047, 'b') + string("aaaaa") + "abc");
+ Verify("aaaaaaa" + string(65536, 'b') + string("aaaaa") + "abc");
+ Verify("abcaaaaaaa" + string(65536, 'b') + string("aaaaa") + "abc");
+}
+
+// Verify max blowup (lots of four-byte copies)
+TEST(Snappy, MaxBlowup) {
+ string input;
+ for (int i = 0; i < 20000; i++) {
+ ACMRandom rnd(i);
+ uint32 bytes = static_cast<uint32>(rnd.Next());
+ input.append(reinterpret_cast<char*>(&bytes), sizeof(bytes));
+ }
+ for (int i = 19999; i >= 0; i--) {
+ ACMRandom rnd(i);
+ uint32 bytes = static_cast<uint32>(rnd.Next());
+ input.append(reinterpret_cast<char*>(&bytes), sizeof(bytes));
+ }
+ Verify(input);
+}
+
+TEST(Snappy, RandomData) {
+ ACMRandom rnd(FLAGS_test_random_seed);
+
+ const int num_ops = 20000;
+ for (int i = 0; i < num_ops; i++) {
+ if ((i % 1000) == 0) {
+ VLOG(0) << "Random op " << i << " of " << num_ops;
+ }
+
+ string x;
+ int len = rnd.Uniform(4096);
+ if (i < 100) {
+ len = 65536 + rnd.Uniform(65536);
+ }
+ while (x.size() < len) {
+ int run_len = 1;
+ if (rnd.OneIn(10)) {
+ run_len = rnd.Skewed(8);
+ }
+ char c = (i < 100) ? rnd.Uniform(256) : rnd.Skewed(3);
+ while (run_len-- > 0 && x.size() < len) {
+ x += c;
+ }
+ }
+
+ Verify(x);
+ }
+}
+
+TEST(Snappy, FourByteOffset) {
+ // The new compressor cannot generate four-byte offsets since
+ // it chops up the input into 32KB pieces. So we hand-emit the
+ // copy manually.
+
+ // The two fragments that make up the input string.
+ string fragment1 = "012345689abcdefghijklmnopqrstuvwxyz";
+ string fragment2 = "some other string";
+
+ // How many times each fragment is emitted.
+ const int n1 = 2;
+ const int n2 = 100000 / fragment2.size();
+ const int length = n1 * fragment1.size() + n2 * fragment2.size();
+
+ string compressed;
+ Varint::Append32(&compressed, length);
+
+ AppendLiteral(&compressed, fragment1);
+ string src = fragment1;
+ for (int i = 0; i < n2; i++) {
+ AppendLiteral(&compressed, fragment2);
+ src += fragment2;
+ }
+ AppendCopy(&compressed, src.size(), fragment1.size());
+ src += fragment1;
+ CHECK_EQ(length, src.size());
+
+ string uncompressed;
+ CHECK(snappy::IsValidCompressedBuffer(compressed.data(), compressed.size()));
+ CHECK(snappy::Uncompress(compressed.data(), compressed.size(),
+ &uncompressed));
+ CHECK_EQ(uncompressed, src);
+}
+
+
+static bool CheckUncompressedLength(const string& compressed,
+ size_t* ulength) {
+ const bool result1 = snappy::GetUncompressedLength(compressed.data(),
+ compressed.size(),
+ ulength);
+
+ snappy::ByteArraySource source(compressed.data(), compressed.size());
+ uint32 length;
+ const bool result2 = snappy::GetUncompressedLength(&source, &length);
+ CHECK_EQ(result1, result2);
+ return result1;
+}
+
+TEST(SnappyCorruption, TruncatedVarint) {
+ string compressed, uncompressed;
+ size_t ulength;
+ compressed.push_back('\xf0');
+ CHECK(!CheckUncompressedLength(compressed, &ulength));
+ CHECK(!snappy::IsValidCompressedBuffer(compressed.data(), compressed.size()));
+ CHECK(!snappy::Uncompress(compressed.data(), compressed.size(),
+ &uncompressed));
+}
+
+TEST(SnappyCorruption, UnterminatedVarint) {
+ string compressed, uncompressed;
+ size_t ulength;
+ compressed.push_back(128);
+ compressed.push_back(128);
+ compressed.push_back(128);
+ compressed.push_back(128);
+ compressed.push_back(128);
+ compressed.push_back(10);
+ CHECK(!CheckUncompressedLength(compressed, &ulength));
+ CHECK(!snappy::IsValidCompressedBuffer(compressed.data(), compressed.size()));
+ CHECK(!snappy::Uncompress(compressed.data(), compressed.size(),
+ &uncompressed));
+}
+
+TEST(Snappy, ReadPastEndOfBuffer) {
+ // Check that we do not read past end of input
+
+ // Make a compressed string that ends with a single-byte literal
+ string compressed;
+ Varint::Append32(&compressed, 1);
+ AppendLiteral(&compressed, "x");
+
+ string uncompressed;
+ DataEndingAtUnreadablePage c(compressed);
+ CHECK(snappy::Uncompress(c.data(), c.size(), &uncompressed));
+ CHECK_EQ(uncompressed, string("x"));
+}
+
+// Check for an infinite loop caused by a copy with offset==0
+TEST(Snappy, ZeroOffsetCopy) {
+ const char* compressed = "\x40\x12\x00\x00";
+ // \x40 Length (must be > kMaxIncrementCopyOverflow)
+ // \x12\x00\x00 Copy with offset==0, length==5
+ char uncompressed[100];
+ EXPECT_FALSE(snappy::RawUncompress(compressed, 4, uncompressed));
+}
+
+TEST(Snappy, ZeroOffsetCopyValidation) {
+ const char* compressed = "\x05\x12\x00\x00";
+ // \x05 Length
+ // \x12\x00\x00 Copy with offset==0, length==5
+ EXPECT_FALSE(snappy::IsValidCompressedBuffer(compressed, 4));
+}
+
+
+namespace {
+
+int TestFindMatchLength(const char* s1, const char *s2, unsigned length) {
+ return snappy::internal::FindMatchLength(s1, s2, s2 + length);
+}
+
+} // namespace
+
+TEST(Snappy, FindMatchLength) {
+ // Exercise all different code paths through the function.
+ // 64-bit version:
+
+ // Hit s1_limit in 64-bit loop, hit s1_limit in single-character loop.
+ EXPECT_EQ(6, TestFindMatchLength("012345", "012345", 6));
+ EXPECT_EQ(11, TestFindMatchLength("01234567abc", "01234567abc", 11));
+
+ // Hit s1_limit in 64-bit loop, find a non-match in single-character loop.
+ EXPECT_EQ(9, TestFindMatchLength("01234567abc", "01234567axc", 9));
+
+ // Same, but edge cases.
+ EXPECT_EQ(11, TestFindMatchLength("01234567abc!", "01234567abc!", 11));
+ EXPECT_EQ(11, TestFindMatchLength("01234567abc!", "01234567abc?", 11));
+
+ // Find non-match at once in first loop.
+ EXPECT_EQ(0, TestFindMatchLength("01234567xxxxxxxx", "?1234567xxxxxxxx", 16));
+ EXPECT_EQ(1, TestFindMatchLength("01234567xxxxxxxx", "0?234567xxxxxxxx", 16));
+ EXPECT_EQ(4, TestFindMatchLength("01234567xxxxxxxx", "01237654xxxxxxxx", 16));
+ EXPECT_EQ(7, TestFindMatchLength("01234567xxxxxxxx", "0123456?xxxxxxxx", 16));
+
+ // Find non-match in first loop after one block.
+ EXPECT_EQ(8, TestFindMatchLength("abcdefgh01234567xxxxxxxx",
+ "abcdefgh?1234567xxxxxxxx", 24));
+ EXPECT_EQ(9, TestFindMatchLength("abcdefgh01234567xxxxxxxx",
+ "abcdefgh0?234567xxxxxxxx", 24));
+ EXPECT_EQ(12, TestFindMatchLength("abcdefgh01234567xxxxxxxx",
+ "abcdefgh01237654xxxxxxxx", 24));
+ EXPECT_EQ(15, TestFindMatchLength("abcdefgh01234567xxxxxxxx",
+ "abcdefgh0123456?xxxxxxxx", 24));
+
+ // 32-bit version:
+
+ // Short matches.
+ EXPECT_EQ(0, TestFindMatchLength("01234567", "?1234567", 8));
+ EXPECT_EQ(1, TestFindMatchLength("01234567", "0?234567", 8));
+ EXPECT_EQ(2, TestFindMatchLength("01234567", "01?34567", 8));
+ EXPECT_EQ(3, TestFindMatchLength("01234567", "012?4567", 8));
+ EXPECT_EQ(4, TestFindMatchLength("01234567", "0123?567", 8));
+ EXPECT_EQ(5, TestFindMatchLength("01234567", "01234?67", 8));
+ EXPECT_EQ(6, TestFindMatchLength("01234567", "012345?7", 8));
+ EXPECT_EQ(7, TestFindMatchLength("01234567", "0123456?", 8));
+ EXPECT_EQ(7, TestFindMatchLength("01234567", "0123456?", 7));
+ EXPECT_EQ(7, TestFindMatchLength("01234567!", "0123456??", 7));
+
+ // Hit s1_limit in 32-bit loop, hit s1_limit in single-character loop.
+ EXPECT_EQ(10, TestFindMatchLength("xxxxxxabcd", "xxxxxxabcd", 10));
+ EXPECT_EQ(10, TestFindMatchLength("xxxxxxabcd?", "xxxxxxabcd?", 10));
+ EXPECT_EQ(13, TestFindMatchLength("xxxxxxabcdef", "xxxxxxabcdef", 13));
+
+ // Same, but edge cases.
+ EXPECT_EQ(12, TestFindMatchLength("xxxxxx0123abc!", "xxxxxx0123abc!", 12));
+ EXPECT_EQ(12, TestFindMatchLength("xxxxxx0123abc!", "xxxxxx0123abc?", 12));
+
+ // Hit s1_limit in 32-bit loop, find a non-match in single-character loop.
+ EXPECT_EQ(11, TestFindMatchLength("xxxxxx0123abc", "xxxxxx0123axc", 13));
+
+ // Find non-match at once in first loop.
+ EXPECT_EQ(6, TestFindMatchLength("xxxxxx0123xxxxxxxx",
+ "xxxxxx?123xxxxxxxx", 18));
+ EXPECT_EQ(7, TestFindMatchLength("xxxxxx0123xxxxxxxx",
+ "xxxxxx0?23xxxxxxxx", 18));
+ EXPECT_EQ(8, TestFindMatchLength("xxxxxx0123xxxxxxxx",
+ "xxxxxx0132xxxxxxxx", 18));
+ EXPECT_EQ(9, TestFindMatchLength("xxxxxx0123xxxxxxxx",
+ "xxxxxx012?xxxxxxxx", 18));
+
+ // Same, but edge cases.
+ EXPECT_EQ(6, TestFindMatchLength("xxxxxx0123", "xxxxxx?123", 10));
+ EXPECT_EQ(7, TestFindMatchLength("xxxxxx0123", "xxxxxx0?23", 10));
+ EXPECT_EQ(8, TestFindMatchLength("xxxxxx0123", "xxxxxx0132", 10));
+ EXPECT_EQ(9, TestFindMatchLength("xxxxxx0123", "xxxxxx012?", 10));
+
+ // Find non-match in first loop after one block.
+ EXPECT_EQ(10, TestFindMatchLength("xxxxxxabcd0123xx",
+ "xxxxxxabcd?123xx", 16));
+ EXPECT_EQ(11, TestFindMatchLength("xxxxxxabcd0123xx",
+ "xxxxxxabcd0?23xx", 16));
+ EXPECT_EQ(12, TestFindMatchLength("xxxxxxabcd0123xx",
+ "xxxxxxabcd0132xx", 16));
+ EXPECT_EQ(13, TestFindMatchLength("xxxxxxabcd0123xx",
+ "xxxxxxabcd012?xx", 16));
+
+ // Same, but edge cases.
+ EXPECT_EQ(10, TestFindMatchLength("xxxxxxabcd0123", "xxxxxxabcd?123", 14));
+ EXPECT_EQ(11, TestFindMatchLength("xxxxxxabcd0123", "xxxxxxabcd0?23", 14));
+ EXPECT_EQ(12, TestFindMatchLength("xxxxxxabcd0123", "xxxxxxabcd0132", 14));
+ EXPECT_EQ(13, TestFindMatchLength("xxxxxxabcd0123", "xxxxxxabcd012?", 14));
+}
+
+TEST(Snappy, FindMatchLengthRandom) {
+ const int kNumTrials = 10000;
+ const int kTypicalLength = 10;
+ ACMRandom rnd(FLAGS_test_random_seed);
+
+ for (int i = 0; i < kNumTrials; i++) {
+ string s, t;
+ char a = rnd.Rand8();
+ char b = rnd.Rand8();
+ while (!rnd.OneIn(kTypicalLength)) {
+ s.push_back(rnd.OneIn(2) ? a : b);
+ t.push_back(rnd.OneIn(2) ? a : b);
+ }
+ DataEndingAtUnreadablePage u(s);
+ DataEndingAtUnreadablePage v(t);
+ int matched = snappy::internal::FindMatchLength(
+ u.data(), v.data(), v.data() + t.size());
+ if (matched == t.size()) {
+ EXPECT_EQ(s, t);
+ } else {
+ EXPECT_NE(s[matched], t[matched]);
+ for (int j = 0; j < matched; j++) {
+ EXPECT_EQ(s[j], t[j]);
+ }
+ }
+ }
+}
+
+
+static void CompressFile(const char* fname) {
+ string fullinput;
+ file::GetContents(fname, &fullinput, file::Defaults()).CheckSuccess();
+
+ string compressed;
+ Compress(fullinput.data(), fullinput.size(), SNAPPY, &compressed, false);
+
+ file::SetContents(string(fname).append(".comp"), compressed, file::Defaults())
+ .CheckSuccess();
+}
+
+static void UncompressFile(const char* fname) {
+ string fullinput;
+ file::GetContents(fname, &fullinput, file::Defaults()).CheckSuccess();
+
+ size_t uncompLength;
+ CHECK(CheckUncompressedLength(fullinput, &uncompLength));
+
+ string uncompressed;
+ uncompressed.resize(uncompLength);
+ CHECK(snappy::Uncompress(fullinput.data(), fullinput.size(), &uncompressed));
+
+ file::SetContents(string(fname).append(".uncomp"), uncompressed,
+ file::Defaults()).CheckSuccess();
+}
+
+static void MeasureFile(const char* fname) {
+ string fullinput;
+ file::GetContents(fname, &fullinput, file::Defaults()).CheckSuccess();
+ printf("%-40s :\n", fname);
+
+ int start_len = (FLAGS_start_len < 0) ? fullinput.size() : FLAGS_start_len;
+ int end_len = fullinput.size();
+ if (FLAGS_end_len >= 0) {
+ end_len = min<int>(fullinput.size(), FLAGS_end_len);
+ }
+ for (int len = start_len; len <= end_len; len++) {
+ const char* const input = fullinput.data();
+ int repeats = (FLAGS_bytes + len) / (len + 1);
+ if (FLAGS_zlib) Measure(input, len, ZLIB, repeats, 1024<<10);
+ if (FLAGS_lzo) Measure(input, len, LZO, repeats, 1024<<10);
+ if (FLAGS_liblzf) Measure(input, len, LIBLZF, repeats, 1024<<10);
+ if (FLAGS_quicklz) Measure(input, len, QUICKLZ, repeats, 1024<<10);
+ if (FLAGS_fastlz) Measure(input, len, FASTLZ, repeats, 1024<<10);
+ if (FLAGS_snappy) Measure(input, len, SNAPPY, repeats, 4096<<10);
+
+ // For block-size based measurements
+ if (0 && FLAGS_snappy) {
+ Measure(input, len, SNAPPY, repeats, 8<<10);
+ Measure(input, len, SNAPPY, repeats, 16<<10);
+ Measure(input, len, SNAPPY, repeats, 32<<10);
+ Measure(input, len, SNAPPY, repeats, 64<<10);
+ Measure(input, len, SNAPPY, repeats, 256<<10);
+ Measure(input, len, SNAPPY, repeats, 1024<<10);
+ }
+ }
+}
+
+static struct {
+ const char* label;
+ const char* filename;
+ size_t size_limit;
+} files[] = {
+ { "html", "html", 0 },
+ { "urls", "urls.10K", 0 },
+ { "jpg", "house.jpg", 0 },
+ { "jpg_200", "house.jpg", 200 },
+ { "pdf", "mapreduce-osdi-1.pdf", 0 },
+ { "html4", "html_x_4", 0 },
+ { "cp", "cp.html", 0 },
+ { "c", "fields.c", 0 },
+ { "lsp", "grammar.lsp", 0 },
+ { "xls", "kennedy.xls", 0 },
+ { "xls_200", "kennedy.xls", 200 },
+ { "txt1", "alice29.txt", 0 },
+ { "txt2", "asyoulik.txt", 0 },
+ { "txt3", "lcet10.txt", 0 },
+ { "txt4", "plrabn12.txt", 0 },
+ { "bin", "ptt5", 0 },
+ { "bin_200", "ptt5", 200 },
+ { "sum", "sum", 0 },
+ { "man", "xargs.1", 0 },
+ { "pb", "geo.protodata", 0 },
+ { "gaviota", "kppkn.gtb", 0 },
+};
+
+static void BM_UFlat(int iters, int arg) {
+ StopBenchmarkTiming();
+
+ // Pick file to process based on "arg"
+ CHECK_GE(arg, 0);
+ CHECK_LT(arg, ARRAYSIZE(files));
+ string contents = ReadTestDataFile(files[arg].filename,
+ files[arg].size_limit);
+
+ string zcontents;
+ snappy::Compress(contents.data(), contents.size(), &zcontents);
+ char* dst = new char[contents.size()];
+
+ SetBenchmarkBytesProcessed(static_cast<int64>(iters) *
+ static_cast<int64>(contents.size()));
+ SetBenchmarkLabel(files[arg].label);
+ StartBenchmarkTiming();
+ while (iters-- > 0) {
+ CHECK(snappy::RawUncompress(zcontents.data(), zcontents.size(), dst));
+ }
+ StopBenchmarkTiming();
+
+ delete[] dst;
+}
+BENCHMARK(BM_UFlat)->DenseRange(0, ARRAYSIZE(files) - 1);
+
+static void BM_UValidate(int iters, int arg) {
+ StopBenchmarkTiming();
+
+ // Pick file to process based on "arg"
+ CHECK_GE(arg, 0);
+ CHECK_LT(arg, ARRAYSIZE(files));
+ string contents = ReadTestDataFile(files[arg].filename,
+ files[arg].size_limit);
+
+ string zcontents;
+ snappy::Compress(contents.data(), contents.size(), &zcontents);
+
+ SetBenchmarkBytesProcessed(static_cast<int64>(iters) *
+ static_cast<int64>(contents.size()));
+ SetBenchmarkLabel(files[arg].label);
+ StartBenchmarkTiming();
+ while (iters-- > 0) {
+ CHECK(snappy::IsValidCompressedBuffer(zcontents.data(), zcontents.size()));
+ }
+ StopBenchmarkTiming();
+}
+BENCHMARK(BM_UValidate)->DenseRange(0, 4);
+
+
+static void BM_ZFlat(int iters, int arg) {
+ StopBenchmarkTiming();
+
+ // Pick file to process based on "arg"
+ CHECK_GE(arg, 0);
+ CHECK_LT(arg, ARRAYSIZE(files));
+ string contents = ReadTestDataFile(files[arg].filename,
+ files[arg].size_limit);
+
+ char* dst = new char[snappy::MaxCompressedLength(contents.size())];
+
+ SetBenchmarkBytesProcessed(static_cast<int64>(iters) *
+ static_cast<int64>(contents.size()));
+ StartBenchmarkTiming();
+
+ size_t zsize = 0;
+ while (iters-- > 0) {
+ snappy::RawCompress(contents.data(), contents.size(), dst, &zsize);
+ }
+ StopBenchmarkTiming();
+ const double compression_ratio =
+ static_cast<double>(zsize) / std::max<size_t>(1, contents.size());
+ SetBenchmarkLabel(StringPrintf("%s (%.2f %%)",
+ files[arg].label, 100.0 * compression_ratio));
+ VLOG(0) << StringPrintf("compression for %s: %zd -> %zd bytes",
+ files[arg].label, contents.size(), zsize);
+ delete[] dst;
+}
+BENCHMARK(BM_ZFlat)->DenseRange(0, ARRAYSIZE(files) - 1);
+
+
+} // namespace snappy
+
+
+int main(int argc, char** argv) {
+ InitGoogle(argv[0], &argc, &argv, true);
+ File::Init();
+ RunSpecifiedBenchmarks();
+
+
+ if (argc >= 2) {
+ for (int arg = 1; arg < argc; arg++) {
+ if (FLAGS_write_compressed) {
+ CompressFile(argv[arg]);
+ } else if (FLAGS_write_uncompressed) {
+ UncompressFile(argv[arg]);
+ } else {
+ MeasureFile(argv[arg]);
+ }
+ }
+ return 0;
+ }
+
+ return RUN_ALL_TESTS();
+}