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authorHans-Christoph Steiner <hans@eds.org>2012-03-30 20:42:12 -0400
committerHans-Christoph Steiner <hans@eds.org>2012-03-30 20:42:12 -0400
commit7bb481fda9ecb134804b49c2ce77ca28f7eea583 (patch)
tree31b520b9914d3e2453968abe375f2c102772c3dc /tool/showjournal.c
Imported Upstream version 2.0.3
Diffstat (limited to 'tool/showjournal.c')
-rw-r--r--tool/showjournal.c139
1 files changed, 139 insertions, 0 deletions
diff --git a/tool/showjournal.c b/tool/showjournal.c
new file mode 100644
index 0000000..5724f52
--- /dev/null
+++ b/tool/showjournal.c
@@ -0,0 +1,139 @@
+/*
+** A utility for printing an SQLite database journal.
+*/
+#include <stdio.h>
+#include <ctype.h>
+#include <stdlib.h>
+#include <string.h>
+
+/*
+** state information
+*/
+static int pageSize = 1024;
+static int sectorSize = 512;
+static FILE *db = 0;
+static int showPageContent = 0;
+static int fileSize = 0;
+static unsigned cksumNonce = 0;
+
+/* Report a memory allocation error */
+static void out_of_memory(void){
+ fprintf(stderr,"Out of memory...\n");
+ exit(1);
+}
+
+/*
+** Read N bytes of memory starting at iOfst into space obtained
+** from malloc().
+*/
+static char *read_content(int N, int iOfst){
+ int got;
+ char *pBuf = malloc(N);
+ if( pBuf==0 ) out_of_memory();
+ fseek(db, iOfst, SEEK_SET);
+ got = fread(pBuf, 1, N, db);
+ if( got<0 ){
+ fprintf(stderr, "I/O error reading %d bytes from %d\n", N, iOfst);
+ memset(pBuf, 0, N);
+ }else if( got<N ){
+ fprintf(stderr, "Short read: got only %d of %d bytes from %d\n",
+ got, N, iOfst);
+ memset(&pBuf[got], 0, N-got);
+ }
+ return pBuf;
+}
+
+/* Print a line of decode output showing a 4-byte integer.
+*/
+static unsigned print_decode_line(
+ unsigned char *aData, /* Content being decoded */
+ int ofst, int nByte, /* Start and size of decode */
+ const char *zMsg /* Message to append */
+){
+ int i, j;
+ unsigned val = aData[ofst];
+ char zBuf[100];
+ sprintf(zBuf, " %03x: %02x", ofst, aData[ofst]);
+ i = strlen(zBuf);
+ for(j=1; j<4; j++){
+ if( j>=nByte ){
+ sprintf(&zBuf[i], " ");
+ }else{
+ sprintf(&zBuf[i], " %02x", aData[ofst+j]);
+ val = val*256 + aData[ofst+j];
+ }
+ i += strlen(&zBuf[i]);
+ }
+ sprintf(&zBuf[i], " %10u", val);
+ printf("%s %s\n", zBuf, zMsg);
+ return val;
+}
+
+/*
+** Read and print a journal header. Store key information (page size, etc)
+** in global variables.
+*/
+static unsigned decode_journal_header(int iOfst){
+ char *pHdr = read_content(64, iOfst);
+ unsigned nPage;
+ printf("Header at offset %d:\n", iOfst);
+ print_decode_line(pHdr, 0, 4, "Header part 1 (3654616569)");
+ print_decode_line(pHdr, 4, 4, "Header part 2 (547447767)");
+ nPage =
+ print_decode_line(pHdr, 8, 4, "page count");
+ cksumNonce =
+ print_decode_line(pHdr, 12, 4, "chksum nonce");
+ print_decode_line(pHdr, 16, 4, "initial database size in pages");
+ sectorSize =
+ print_decode_line(pHdr, 20, 4, "sector size");
+ pageSize =
+ print_decode_line(pHdr, 24, 4, "page size");
+ print_decode_line(pHdr, 28, 4, "zero");
+ print_decode_line(pHdr, 32, 4, "zero");
+ print_decode_line(pHdr, 36, 4, "zero");
+ print_decode_line(pHdr, 40, 4, "zero");
+ free(pHdr);
+ return nPage;
+}
+
+static void print_page(int iOfst){
+ unsigned char *aData;
+ char zTitle[50];
+ aData = read_content(pageSize+8, iOfst);
+ sprintf(zTitle, "page number for page at offset %d", iOfst);
+ print_decode_line(aData, 0, 4, zTitle);
+ free(aData);
+}
+
+int main(int argc, char **argv){
+ int rc;
+ int nPage, cnt;
+ int iOfst;
+ if( argc!=2 ){
+ fprintf(stderr,"Usage: %s FILENAME\n", argv[0]);
+ exit(1);
+ }
+ db = fopen(argv[1], "rb");
+ if( db==0 ){
+ fprintf(stderr,"%s: can't open %s\n", argv[0], argv[1]);
+ exit(1);
+ }
+ fseek(db, 0, SEEK_END);
+ fileSize = ftell(db);
+ printf("journal file size: %d bytes\n", fileSize);
+ fseek(db, 0, SEEK_SET);
+ iOfst = 0;
+ while( iOfst<fileSize ){
+ cnt = nPage = (int)decode_journal_header(iOfst);
+ if( cnt==0 ){
+ cnt = (fileSize - sectorSize)/(pageSize+8);
+ }
+ iOfst += sectorSize;
+ while( cnt && iOfst<fileSize ){
+ print_page(iOfst);
+ iOfst += pageSize+8;
+ }
+ iOfst = (iOfst/sectorSize + 1)*sectorSize;
+ }
+ fclose(db);
+}