diff options
author | Hans-Christoph Steiner <hans@eds.org> | 2012-03-30 20:42:12 -0400 |
---|---|---|
committer | Hans-Christoph Steiner <hans@eds.org> | 2012-03-30 20:42:12 -0400 |
commit | 7bb481fda9ecb134804b49c2ce77ca28f7eea583 (patch) | |
tree | 31b520b9914d3e2453968abe375f2c102772c3dc /src/test_quota.c |
Imported Upstream version 2.0.3
Diffstat (limited to 'src/test_quota.c')
-rw-r--r-- | src/test_quota.c | 1105 |
1 files changed, 1105 insertions, 0 deletions
diff --git a/src/test_quota.c b/src/test_quota.c new file mode 100644 index 0000000..74d1a6d --- /dev/null +++ b/src/test_quota.c @@ -0,0 +1,1105 @@ +/* +** 2010 September 31 +** +** The author disclaims copyright to this source code. In place of +** a legal notice, here is a blessing: +** +** May you do good and not evil. +** May you find forgiveness for yourself and forgive others. +** May you share freely, never taking more than you give. +** +************************************************************************* +** +** This file contains a VFS "shim" - a layer that sits in between the +** pager and the real VFS. +** +** This particular shim enforces a quota system on files. One or more +** database files are in a "quota group" that is defined by a GLOB +** pattern. A quota is set for the combined size of all files in the +** the group. A quota of zero means "no limit". If the total size +** of all files in the quota group is greater than the limit, then +** write requests that attempt to enlarge a file fail with SQLITE_FULL. +** +** However, before returning SQLITE_FULL, the write requests invoke +** a callback function that is configurable for each quota group. +** This callback has the opportunity to enlarge the quota. If the +** callback does enlarge the quota such that the total size of all +** files within the group is less than the new quota, then the write +** continues as if nothing had happened. +*/ +#include "sqlite3.h" +#include <string.h> +#include <assert.h> + +/* +** For an build without mutexes, no-op the mutex calls. +*/ +#if defined(SQLITE_THREADSAFE) && SQLITE_THREADSAFE==0 +#define sqlite3_mutex_alloc(X) ((sqlite3_mutex*)8) +#define sqlite3_mutex_free(X) +#define sqlite3_mutex_enter(X) +#define sqlite3_mutex_try(X) SQLITE_OK +#define sqlite3_mutex_leave(X) +#define sqlite3_mutex_held(X) ((void)(X),1) +#define sqlite3_mutex_notheld(X) ((void)(X),1) +#endif /* SQLITE_THREADSAFE==0 */ + + +/************************ Object Definitions ******************************/ + +/* Forward declaration of all object types */ +typedef struct quotaGroup quotaGroup; +typedef struct quotaConn quotaConn; +typedef struct quotaFile quotaFile; + +/* +** A "quota group" is a collection of files whose collective size we want +** to limit. Each quota group is defined by a GLOB pattern. +** +** There is an instance of the following object for each defined quota +** group. This object records the GLOB pattern that defines which files +** belong to the quota group. The object also remembers the size limit +** for the group (the quota) and the callback to be invoked when the +** sum of the sizes of the files within the group goes over the limit. +** +** A quota group must be established (using sqlite3_quota_set(...)) +** prior to opening any of the database connections that access files +** within the quota group. +*/ +struct quotaGroup { + const char *zPattern; /* Filename pattern to be quotaed */ + sqlite3_int64 iLimit; /* Upper bound on total file size */ + sqlite3_int64 iSize; /* Current size of all files */ + void (*xCallback)( /* Callback invoked when going over quota */ + const char *zFilename, /* Name of file whose size increases */ + sqlite3_int64 *piLimit, /* IN/OUT: The current limit */ + sqlite3_int64 iSize, /* Total size of all files in the group */ + void *pArg /* Client data */ + ); + void *pArg; /* Third argument to the xCallback() */ + void (*xDestroy)(void*); /* Optional destructor for pArg */ + quotaGroup *pNext, **ppPrev; /* Doubly linked list of all quota objects */ + quotaFile *pFiles; /* Files within this group */ +}; + +/* +** An instance of this structure represents a single file that is part +** of a quota group. A single file can be opened multiple times. In +** order keep multiple openings of the same file from causing the size +** of the file to count against the quota multiple times, each file +** has a unique instance of this object and multiple open connections +** to the same file each point to a single instance of this object. +*/ +struct quotaFile { + char *zFilename; /* Name of this file */ + quotaGroup *pGroup; /* Quota group to which this file belongs */ + sqlite3_int64 iSize; /* Current size of this file */ + int nRef; /* Number of times this file is open */ + int deleteOnClose; /* True to delete this file when it closes */ + quotaFile *pNext, **ppPrev; /* Linked list of files in the same group */ +}; + +/* +** An instance of the following object represents each open connection +** to a file that participates in quota tracking. This object is a +** subclass of sqlite3_file. The sqlite3_file object for the underlying +** VFS is appended to this structure. +*/ +struct quotaConn { + sqlite3_file base; /* Base class - must be first */ + quotaFile *pFile; /* The underlying file */ + /* The underlying VFS sqlite3_file is appended to this object */ +}; + +/************************* Global Variables **********************************/ +/* +** All global variables used by this file are containing within the following +** gQuota structure. +*/ +static struct { + /* The pOrigVfs is the real, original underlying VFS implementation. + ** Most operations pass-through to the real VFS. This value is read-only + ** during operation. It is only modified at start-time and thus does not + ** require a mutex. + */ + sqlite3_vfs *pOrigVfs; + + /* The sThisVfs is the VFS structure used by this shim. It is initialized + ** at start-time and thus does not require a mutex + */ + sqlite3_vfs sThisVfs; + + /* The sIoMethods defines the methods used by sqlite3_file objects + ** associated with this shim. It is initialized at start-time and does + ** not require a mutex. + ** + ** When the underlying VFS is called to open a file, it might return + ** either a version 1 or a version 2 sqlite3_file object. This shim + ** has to create a wrapper sqlite3_file of the same version. Hence + ** there are two I/O method structures, one for version 1 and the other + ** for version 2. + */ + sqlite3_io_methods sIoMethodsV1; + sqlite3_io_methods sIoMethodsV2; + + /* True when this shim as been initialized. + */ + int isInitialized; + + /* For run-time access any of the other global data structures in this + ** shim, the following mutex must be held. + */ + sqlite3_mutex *pMutex; + + /* List of quotaGroup objects. + */ + quotaGroup *pGroup; + +} gQuota; + +/************************* Utility Routines *********************************/ +/* +** Acquire and release the mutex used to serialize access to the +** list of quotaGroups. +*/ +static void quotaEnter(void){ sqlite3_mutex_enter(gQuota.pMutex); } +static void quotaLeave(void){ sqlite3_mutex_leave(gQuota.pMutex); } + +/* Count the number of open files in a quotaGroup +*/ +static int quotaGroupOpenFileCount(quotaGroup *pGroup){ + int N = 0; + quotaFile *pFile = pGroup->pFiles; + while( pFile ){ + if( pFile->nRef ) N++; + pFile = pFile->pNext; + } + return N; +} + +/* Remove a file from a quota group. +*/ +static void quotaRemoveFile(quotaFile *pFile){ + quotaGroup *pGroup = pFile->pGroup; + pGroup->iSize -= pFile->iSize; + *pFile->ppPrev = pFile->pNext; + if( pFile->pNext ) pFile->pNext->ppPrev = pFile->ppPrev; + sqlite3_free(pFile); +} + +/* Remove all files from a quota group. It is always the case that +** all files will be closed when this routine is called. +*/ +static void quotaRemoveAllFiles(quotaGroup *pGroup){ + while( pGroup->pFiles ){ + assert( pGroup->pFiles->nRef==0 ); + quotaRemoveFile(pGroup->pFiles); + } +} + + +/* If the reference count and threshold for a quotaGroup are both +** zero, then destroy the quotaGroup. +*/ +static void quotaGroupDeref(quotaGroup *pGroup){ + if( pGroup->iLimit==0 && quotaGroupOpenFileCount(pGroup)==0 ){ + quotaRemoveAllFiles(pGroup); + *pGroup->ppPrev = pGroup->pNext; + if( pGroup->pNext ) pGroup->pNext->ppPrev = pGroup->ppPrev; + if( pGroup->xDestroy ) pGroup->xDestroy(pGroup->pArg); + sqlite3_free(pGroup); + } +} + +/* +** Return TRUE if string z matches glob pattern zGlob. +** +** Globbing rules: +** +** '*' Matches any sequence of zero or more characters. +** +** '?' Matches exactly one character. +** +** [...] Matches one character from the enclosed list of +** characters. +** +** [^...] Matches one character not in the enclosed list. +** +*/ +static int quotaStrglob(const char *zGlob, const char *z){ + int c, c2; + int invert; + int seen; + + while( (c = (*(zGlob++)))!=0 ){ + if( c=='*' ){ + while( (c=(*(zGlob++))) == '*' || c=='?' ){ + if( c=='?' && (*(z++))==0 ) return 0; + } + if( c==0 ){ + return 1; + }else if( c=='[' ){ + while( *z && quotaStrglob(zGlob-1,z)==0 ){ + z++; + } + return (*z)!=0; + } + while( (c2 = (*(z++)))!=0 ){ + while( c2!=c ){ + c2 = *(z++); + if( c2==0 ) return 0; + } + if( quotaStrglob(zGlob,z) ) return 1; + } + return 0; + }else if( c=='?' ){ + if( (*(z++))==0 ) return 0; + }else if( c=='[' ){ + int prior_c = 0; + seen = 0; + invert = 0; + c = *(z++); + if( c==0 ) return 0; + c2 = *(zGlob++); + if( c2=='^' ){ + invert = 1; + c2 = *(zGlob++); + } + if( c2==']' ){ + if( c==']' ) seen = 1; + c2 = *(zGlob++); + } + while( c2 && c2!=']' ){ + if( c2=='-' && zGlob[0]!=']' && zGlob[0]!=0 && prior_c>0 ){ + c2 = *(zGlob++); + if( c>=prior_c && c<=c2 ) seen = 1; + prior_c = 0; + }else{ + if( c==c2 ){ + seen = 1; + } + prior_c = c2; + } + c2 = *(zGlob++); + } + if( c2==0 || (seen ^ invert)==0 ) return 0; + }else{ + if( c!=(*(z++)) ) return 0; + } + } + return *z==0; +} + + +/* Find a quotaGroup given the filename. +** +** Return a pointer to the quotaGroup object. Return NULL if not found. +*/ +static quotaGroup *quotaGroupFind(const char *zFilename){ + quotaGroup *p; + for(p=gQuota.pGroup; p && quotaStrglob(p->zPattern, zFilename)==0; + p=p->pNext){} + return p; +} + +/* Translate an sqlite3_file* that is really a quotaConn* into +** the sqlite3_file* for the underlying original VFS. +*/ +static sqlite3_file *quotaSubOpen(sqlite3_file *pConn){ + quotaConn *p = (quotaConn*)pConn; + return (sqlite3_file*)&p[1]; +} + +/* Find a file in a quota group and return a pointer to that file. +** Return NULL if the file is not in the group. +*/ +static quotaFile *quotaFindFile(quotaGroup *pGroup, const char *zName){ + quotaFile *pFile = pGroup->pFiles; + while( pFile && strcmp(pFile->zFilename, zName)!=0 ){ + pFile = pFile->pNext; + } + return pFile; +} + +/************************* VFS Method Wrappers *****************************/ +/* +** This is the xOpen method used for the "quota" VFS. +** +** Most of the work is done by the underlying original VFS. This method +** simply links the new file into the appropriate quota group if it is a +** file that needs to be tracked. +*/ +static int quotaOpen( + sqlite3_vfs *pVfs, /* The quota VFS */ + const char *zName, /* Name of file to be opened */ + sqlite3_file *pConn, /* Fill in this file descriptor */ + int flags, /* Flags to control the opening */ + int *pOutFlags /* Flags showing results of opening */ +){ + int rc; /* Result code */ + quotaConn *pQuotaOpen; /* The new quota file descriptor */ + quotaFile *pFile; /* Corresponding quotaFile obj */ + quotaGroup *pGroup; /* The group file belongs to */ + sqlite3_file *pSubOpen; /* Real file descriptor */ + sqlite3_vfs *pOrigVfs = gQuota.pOrigVfs; /* Real VFS */ + + /* If the file is not a main database file or a WAL, then use the + ** normal xOpen method. + */ + if( (flags & (SQLITE_OPEN_MAIN_DB|SQLITE_OPEN_WAL))==0 ){ + return pOrigVfs->xOpen(pOrigVfs, zName, pConn, flags, pOutFlags); + } + + /* If the name of the file does not match any quota group, then + ** use the normal xOpen method. + */ + quotaEnter(); + pGroup = quotaGroupFind(zName); + if( pGroup==0 ){ + rc = pOrigVfs->xOpen(pOrigVfs, zName, pConn, flags, pOutFlags); + }else{ + /* If we get to this point, it means the file needs to be quota tracked. + */ + pQuotaOpen = (quotaConn*)pConn; + pSubOpen = quotaSubOpen(pConn); + rc = pOrigVfs->xOpen(pOrigVfs, zName, pSubOpen, flags, pOutFlags); + if( rc==SQLITE_OK ){ + pFile = quotaFindFile(pGroup, zName); + if( pFile==0 ){ + int nName = strlen(zName); + pFile = (quotaFile *)sqlite3_malloc( sizeof(*pFile) + nName + 1 ); + if( pFile==0 ){ + quotaLeave(); + pSubOpen->pMethods->xClose(pSubOpen); + return SQLITE_NOMEM; + } + memset(pFile, 0, sizeof(*pFile)); + pFile->zFilename = (char*)&pFile[1]; + memcpy(pFile->zFilename, zName, nName+1); + pFile->pNext = pGroup->pFiles; + if( pGroup->pFiles ) pGroup->pFiles->ppPrev = &pFile->pNext; + pFile->ppPrev = &pGroup->pFiles; + pGroup->pFiles = pFile; + pFile->pGroup = pGroup; + pFile->deleteOnClose = (flags & SQLITE_OPEN_DELETEONCLOSE)!=0; + } + pFile->nRef++; + pQuotaOpen->pFile = pFile; + if( pSubOpen->pMethods->iVersion==1 ){ + pQuotaOpen->base.pMethods = &gQuota.sIoMethodsV1; + }else{ + pQuotaOpen->base.pMethods = &gQuota.sIoMethodsV2; + } + } + } + quotaLeave(); + return rc; +} + +/* +** This is the xDelete method used for the "quota" VFS. +** +** If the file being deleted is part of the quota group, then reduce +** the size of the quota group accordingly. And remove the file from +** the set of files in the quota group. +*/ +static int quotaDelete( + sqlite3_vfs *pVfs, /* The quota VFS */ + const char *zName, /* Name of file to be deleted */ + int syncDir /* Do a directory sync after deleting */ +){ + int rc; /* Result code */ + quotaFile *pFile; /* Files in the quota */ + quotaGroup *pGroup; /* The group file belongs to */ + sqlite3_vfs *pOrigVfs = gQuota.pOrigVfs; /* Real VFS */ + + /* Do the actual file delete */ + rc = pOrigVfs->xDelete(pOrigVfs, zName, syncDir); + + /* If the file just deleted is a member of a quota group, then remove + ** it from that quota group. + */ + if( rc==SQLITE_OK ){ + quotaEnter(); + pGroup = quotaGroupFind(zName); + if( pGroup ){ + pFile = quotaFindFile(pGroup, zName); + if( pFile ){ + if( pFile->nRef ){ + pFile->deleteOnClose = 1; + }else{ + quotaRemoveFile(pFile); + quotaGroupDeref(pGroup); + } + } + } + quotaLeave(); + } + return rc; +} + + +/************************ I/O Method Wrappers *******************************/ + +/* xClose requests get passed through to the original VFS. But we +** also have to unlink the quotaConn from the quotaFile and quotaGroup. +** The quotaFile and/or quotaGroup are freed if they are no longer in use. +*/ +static int quotaClose(sqlite3_file *pConn){ + quotaConn *p = (quotaConn*)pConn; + quotaFile *pFile = p->pFile; + sqlite3_file *pSubOpen = quotaSubOpen(pConn); + int rc; + rc = pSubOpen->pMethods->xClose(pSubOpen); + quotaEnter(); + pFile->nRef--; + if( pFile->nRef==0 ){ + quotaGroup *pGroup = pFile->pGroup; + if( pFile->deleteOnClose ) quotaRemoveFile(pFile); + quotaGroupDeref(pGroup); + } + quotaLeave(); + return rc; +} + +/* Pass xRead requests directory thru to the original VFS without +** further processing. +*/ +static int quotaRead( + sqlite3_file *pConn, + void *pBuf, + int iAmt, + sqlite3_int64 iOfst +){ + sqlite3_file *pSubOpen = quotaSubOpen(pConn); + return pSubOpen->pMethods->xRead(pSubOpen, pBuf, iAmt, iOfst); +} + +/* Check xWrite requests to see if they expand the file. If they do, +** the perform a quota check before passing them through to the +** original VFS. +*/ +static int quotaWrite( + sqlite3_file *pConn, + const void *pBuf, + int iAmt, + sqlite3_int64 iOfst +){ + quotaConn *p = (quotaConn*)pConn; + sqlite3_file *pSubOpen = quotaSubOpen(pConn); + sqlite3_int64 iEnd = iOfst+iAmt; + quotaGroup *pGroup; + quotaFile *pFile = p->pFile; + sqlite3_int64 szNew; + + if( pFile->iSize<iEnd ){ + pGroup = pFile->pGroup; + quotaEnter(); + szNew = pGroup->iSize - pFile->iSize + iEnd; + if( szNew>pGroup->iLimit && pGroup->iLimit>0 ){ + if( pGroup->xCallback ){ + pGroup->xCallback(pFile->zFilename, &pGroup->iLimit, szNew, + pGroup->pArg); + } + if( szNew>pGroup->iLimit && pGroup->iLimit>0 ){ + quotaLeave(); + return SQLITE_FULL; + } + } + pGroup->iSize = szNew; + pFile->iSize = iEnd; + quotaLeave(); + } + return pSubOpen->pMethods->xWrite(pSubOpen, pBuf, iAmt, iOfst); +} + +/* Pass xTruncate requests thru to the original VFS. If the +** success, update the file size. +*/ +static int quotaTruncate(sqlite3_file *pConn, sqlite3_int64 size){ + quotaConn *p = (quotaConn*)pConn; + sqlite3_file *pSubOpen = quotaSubOpen(pConn); + int rc = pSubOpen->pMethods->xTruncate(pSubOpen, size); + quotaFile *pFile = p->pFile; + quotaGroup *pGroup; + if( rc==SQLITE_OK ){ + quotaEnter(); + pGroup = pFile->pGroup; + pGroup->iSize -= pFile->iSize; + pFile->iSize = size; + pGroup->iSize += size; + quotaLeave(); + } + return rc; +} + +/* Pass xSync requests through to the original VFS without change +*/ +static int quotaSync(sqlite3_file *pConn, int flags){ + sqlite3_file *pSubOpen = quotaSubOpen(pConn); + return pSubOpen->pMethods->xSync(pSubOpen, flags); +} + +/* Pass xFileSize requests through to the original VFS but then +** update the quotaGroup with the new size before returning. +*/ +static int quotaFileSize(sqlite3_file *pConn, sqlite3_int64 *pSize){ + quotaConn *p = (quotaConn*)pConn; + sqlite3_file *pSubOpen = quotaSubOpen(pConn); + quotaFile *pFile = p->pFile; + quotaGroup *pGroup; + sqlite3_int64 sz; + int rc; + + rc = pSubOpen->pMethods->xFileSize(pSubOpen, &sz); + if( rc==SQLITE_OK ){ + quotaEnter(); + pGroup = pFile->pGroup; + pGroup->iSize -= pFile->iSize; + pFile->iSize = sz; + pGroup->iSize += sz; + quotaLeave(); + *pSize = sz; + } + return rc; +} + +/* Pass xLock requests through to the original VFS unchanged. +*/ +static int quotaLock(sqlite3_file *pConn, int lock){ + sqlite3_file *pSubOpen = quotaSubOpen(pConn); + return pSubOpen->pMethods->xLock(pSubOpen, lock); +} + +/* Pass xUnlock requests through to the original VFS unchanged. +*/ +static int quotaUnlock(sqlite3_file *pConn, int lock){ + sqlite3_file *pSubOpen = quotaSubOpen(pConn); + return pSubOpen->pMethods->xUnlock(pSubOpen, lock); +} + +/* Pass xCheckReservedLock requests through to the original VFS unchanged. +*/ +static int quotaCheckReservedLock(sqlite3_file *pConn, int *pResOut){ + sqlite3_file *pSubOpen = quotaSubOpen(pConn); + return pSubOpen->pMethods->xCheckReservedLock(pSubOpen, pResOut); +} + +/* Pass xFileControl requests through to the original VFS unchanged. +*/ +static int quotaFileControl(sqlite3_file *pConn, int op, void *pArg){ + sqlite3_file *pSubOpen = quotaSubOpen(pConn); + return pSubOpen->pMethods->xFileControl(pSubOpen, op, pArg); +} + +/* Pass xSectorSize requests through to the original VFS unchanged. +*/ +static int quotaSectorSize(sqlite3_file *pConn){ + sqlite3_file *pSubOpen = quotaSubOpen(pConn); + return pSubOpen->pMethods->xSectorSize(pSubOpen); +} + +/* Pass xDeviceCharacteristics requests through to the original VFS unchanged. +*/ +static int quotaDeviceCharacteristics(sqlite3_file *pConn){ + sqlite3_file *pSubOpen = quotaSubOpen(pConn); + return pSubOpen->pMethods->xDeviceCharacteristics(pSubOpen); +} + +/* Pass xShmMap requests through to the original VFS unchanged. +*/ +static int quotaShmMap( + sqlite3_file *pConn, /* Handle open on database file */ + int iRegion, /* Region to retrieve */ + int szRegion, /* Size of regions */ + int bExtend, /* True to extend file if necessary */ + void volatile **pp /* OUT: Mapped memory */ +){ + sqlite3_file *pSubOpen = quotaSubOpen(pConn); + return pSubOpen->pMethods->xShmMap(pSubOpen, iRegion, szRegion, bExtend, pp); +} + +/* Pass xShmLock requests through to the original VFS unchanged. +*/ +static int quotaShmLock( + sqlite3_file *pConn, /* Database file holding the shared memory */ + int ofst, /* First lock to acquire or release */ + int n, /* Number of locks to acquire or release */ + int flags /* What to do with the lock */ +){ + sqlite3_file *pSubOpen = quotaSubOpen(pConn); + return pSubOpen->pMethods->xShmLock(pSubOpen, ofst, n, flags); +} + +/* Pass xShmBarrier requests through to the original VFS unchanged. +*/ +static void quotaShmBarrier(sqlite3_file *pConn){ + sqlite3_file *pSubOpen = quotaSubOpen(pConn); + pSubOpen->pMethods->xShmBarrier(pSubOpen); +} + +/* Pass xShmUnmap requests through to the original VFS unchanged. +*/ +static int quotaShmUnmap(sqlite3_file *pConn, int deleteFlag){ + sqlite3_file *pSubOpen = quotaSubOpen(pConn); + return pSubOpen->pMethods->xShmUnmap(pSubOpen, deleteFlag); +} + +/************************** Public Interfaces *****************************/ +/* +** Initialize the quota VFS shim. Use the VFS named zOrigVfsName +** as the VFS that does the actual work. Use the default if +** zOrigVfsName==NULL. +** +** The quota VFS shim is named "quota". It will become the default +** VFS if makeDefault is non-zero. +** +** THIS ROUTINE IS NOT THREADSAFE. Call this routine exactly once +** during start-up. +*/ +int sqlite3_quota_initialize(const char *zOrigVfsName, int makeDefault){ + sqlite3_vfs *pOrigVfs; + if( gQuota.isInitialized ) return SQLITE_MISUSE; + pOrigVfs = sqlite3_vfs_find(zOrigVfsName); + if( pOrigVfs==0 ) return SQLITE_ERROR; + assert( pOrigVfs!=&gQuota.sThisVfs ); + gQuota.pMutex = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST); + if( !gQuota.pMutex ){ + return SQLITE_NOMEM; + } + gQuota.isInitialized = 1; + gQuota.pOrigVfs = pOrigVfs; + gQuota.sThisVfs = *pOrigVfs; + gQuota.sThisVfs.xOpen = quotaOpen; + gQuota.sThisVfs.xDelete = quotaDelete; + gQuota.sThisVfs.szOsFile += sizeof(quotaConn); + gQuota.sThisVfs.zName = "quota"; + gQuota.sIoMethodsV1.iVersion = 1; + gQuota.sIoMethodsV1.xClose = quotaClose; + gQuota.sIoMethodsV1.xRead = quotaRead; + gQuota.sIoMethodsV1.xWrite = quotaWrite; + gQuota.sIoMethodsV1.xTruncate = quotaTruncate; + gQuota.sIoMethodsV1.xSync = quotaSync; + gQuota.sIoMethodsV1.xFileSize = quotaFileSize; + gQuota.sIoMethodsV1.xLock = quotaLock; + gQuota.sIoMethodsV1.xUnlock = quotaUnlock; + gQuota.sIoMethodsV1.xCheckReservedLock = quotaCheckReservedLock; + gQuota.sIoMethodsV1.xFileControl = quotaFileControl; + gQuota.sIoMethodsV1.xSectorSize = quotaSectorSize; + gQuota.sIoMethodsV1.xDeviceCharacteristics = quotaDeviceCharacteristics; + gQuota.sIoMethodsV2 = gQuota.sIoMethodsV1; + gQuota.sIoMethodsV2.iVersion = 2; + gQuota.sIoMethodsV2.xShmMap = quotaShmMap; + gQuota.sIoMethodsV2.xShmLock = quotaShmLock; + gQuota.sIoMethodsV2.xShmBarrier = quotaShmBarrier; + gQuota.sIoMethodsV2.xShmUnmap = quotaShmUnmap; + sqlite3_vfs_register(&gQuota.sThisVfs, makeDefault); + return SQLITE_OK; +} + +/* +** Shutdown the quota system. +** +** All SQLite database connections must be closed before calling this +** routine. +** +** THIS ROUTINE IS NOT THREADSAFE. Call this routine exactly once while +** shutting down in order to free all remaining quota groups. +*/ +int sqlite3_quota_shutdown(void){ + quotaGroup *pGroup; + if( gQuota.isInitialized==0 ) return SQLITE_MISUSE; + for(pGroup=gQuota.pGroup; pGroup; pGroup=pGroup->pNext){ + if( quotaGroupOpenFileCount(pGroup)>0 ) return SQLITE_MISUSE; + } + while( gQuota.pGroup ){ + pGroup = gQuota.pGroup; + gQuota.pGroup = pGroup->pNext; + pGroup->iLimit = 0; + assert( quotaGroupOpenFileCount(pGroup)==0 ); + quotaGroupDeref(pGroup); + } + gQuota.isInitialized = 0; + sqlite3_mutex_free(gQuota.pMutex); + sqlite3_vfs_unregister(&gQuota.sThisVfs); + memset(&gQuota, 0, sizeof(gQuota)); + return SQLITE_OK; +} + +/* +** Create or destroy a quota group. +** +** The quota group is defined by the zPattern. When calling this routine +** with a zPattern for a quota group that already exists, this routine +** merely updates the iLimit, xCallback, and pArg values for that quota +** group. If zPattern is new, then a new quota group is created. +** +** If the iLimit for a quota group is set to zero, then the quota group +** is disabled and will be deleted when the last database connection using +** the quota group is closed. +** +** Calling this routine on a zPattern that does not exist and with a +** zero iLimit is a no-op. +** +** A quota group must exist with a non-zero iLimit prior to opening +** database connections if those connections are to participate in the +** quota group. Creating a quota group does not affect database connections +** that are already open. +*/ +int sqlite3_quota_set( + const char *zPattern, /* The filename pattern */ + sqlite3_int64 iLimit, /* New quota to set for this quota group */ + void (*xCallback)( /* Callback invoked when going over quota */ + const char *zFilename, /* Name of file whose size increases */ + sqlite3_int64 *piLimit, /* IN/OUT: The current limit */ + sqlite3_int64 iSize, /* Total size of all files in the group */ + void *pArg /* Client data */ + ), + void *pArg, /* client data passed thru to callback */ + void (*xDestroy)(void*) /* Optional destructor for pArg */ +){ + quotaGroup *pGroup; + quotaEnter(); + pGroup = gQuota.pGroup; + while( pGroup && strcmp(pGroup->zPattern, zPattern)!=0 ){ + pGroup = pGroup->pNext; + } + if( pGroup==0 ){ + int nPattern = strlen(zPattern); + if( iLimit<=0 ){ + quotaLeave(); + return SQLITE_OK; + } + pGroup = (quotaGroup *)sqlite3_malloc( sizeof(*pGroup) + nPattern + 1 ); + if( pGroup==0 ){ + quotaLeave(); + return SQLITE_NOMEM; + } + memset(pGroup, 0, sizeof(*pGroup)); + pGroup->zPattern = (char*)&pGroup[1]; + memcpy((char *)pGroup->zPattern, zPattern, nPattern+1); + if( gQuota.pGroup ) gQuota.pGroup->ppPrev = &pGroup->pNext; + pGroup->pNext = gQuota.pGroup; + pGroup->ppPrev = &gQuota.pGroup; + gQuota.pGroup = pGroup; + } + pGroup->iLimit = iLimit; + pGroup->xCallback = xCallback; + if( pGroup->xDestroy && pGroup->pArg!=pArg ){ + pGroup->xDestroy(pGroup->pArg); + } + pGroup->pArg = pArg; + pGroup->xDestroy = xDestroy; + quotaGroupDeref(pGroup); + quotaLeave(); + return SQLITE_OK; +} + +/* +** Bring the named file under quota management. Or if it is already under +** management, update its size. +*/ +int sqlite3_quota_file(const char *zFilename){ + char *zFull; + sqlite3_file *fd; + int rc; + int outFlags = 0; + sqlite3_int64 iSize; + fd = sqlite3_malloc(gQuota.sThisVfs.szOsFile + gQuota.sThisVfs.mxPathname+1); + if( fd==0 ) return SQLITE_NOMEM; + zFull = gQuota.sThisVfs.szOsFile + (char*)fd; + rc = gQuota.pOrigVfs->xFullPathname(gQuota.pOrigVfs, zFilename, + gQuota.sThisVfs.mxPathname+1, zFull); + if( rc==SQLITE_OK ){ + rc = quotaOpen(&gQuota.sThisVfs, zFull, fd, + SQLITE_OPEN_READONLY | SQLITE_OPEN_MAIN_DB, &outFlags); + } + if( rc==SQLITE_OK ){ + fd->pMethods->xFileSize(fd, &iSize); + fd->pMethods->xClose(fd); + }else if( rc==SQLITE_CANTOPEN ){ + quotaGroup *pGroup; + quotaFile *pFile; + quotaEnter(); + pGroup = quotaGroupFind(zFull); + if( pGroup ){ + pFile = quotaFindFile(pGroup, zFull); + if( pFile ) quotaRemoveFile(pFile); + } + quotaLeave(); + } + sqlite3_free(fd); + return rc; +} + + +/***************************** Test Code ***********************************/ +#ifdef SQLITE_TEST +#include <tcl.h> + +/* +** Argument passed to a TCL quota-over-limit callback. +*/ +typedef struct TclQuotaCallback TclQuotaCallback; +struct TclQuotaCallback { + Tcl_Interp *interp; /* Interpreter in which to run the script */ + Tcl_Obj *pScript; /* Script to be run */ +}; + +extern const char *sqlite3TestErrorName(int); + + +/* +** This is the callback from a quota-over-limit. +*/ +static void tclQuotaCallback( + const char *zFilename, /* Name of file whose size increases */ + sqlite3_int64 *piLimit, /* IN/OUT: The current limit */ + sqlite3_int64 iSize, /* Total size of all files in the group */ + void *pArg /* Client data */ +){ + TclQuotaCallback *p; /* Callback script object */ + Tcl_Obj *pEval; /* Script to evaluate */ + Tcl_Obj *pVarname; /* Name of variable to pass as 2nd arg */ + unsigned int rnd; /* Random part of pVarname */ + int rc; /* Tcl error code */ + + p = (TclQuotaCallback *)pArg; + if( p==0 ) return; + + pVarname = Tcl_NewStringObj("::piLimit_", -1); + Tcl_IncrRefCount(pVarname); + sqlite3_randomness(sizeof(rnd), (void *)&rnd); + Tcl_AppendObjToObj(pVarname, Tcl_NewIntObj((int)(rnd&0x7FFFFFFF))); + Tcl_ObjSetVar2(p->interp, pVarname, 0, Tcl_NewWideIntObj(*piLimit), 0); + + pEval = Tcl_DuplicateObj(p->pScript); + Tcl_IncrRefCount(pEval); + Tcl_ListObjAppendElement(0, pEval, Tcl_NewStringObj(zFilename, -1)); + Tcl_ListObjAppendElement(0, pEval, pVarname); + Tcl_ListObjAppendElement(0, pEval, Tcl_NewWideIntObj(iSize)); + rc = Tcl_EvalObjEx(p->interp, pEval, TCL_EVAL_GLOBAL); + + if( rc==TCL_OK ){ + Tcl_Obj *pLimit = Tcl_ObjGetVar2(p->interp, pVarname, 0, 0); + rc = Tcl_GetWideIntFromObj(p->interp, pLimit, piLimit); + Tcl_UnsetVar(p->interp, Tcl_GetString(pVarname), 0); + } + + Tcl_DecrRefCount(pEval); + Tcl_DecrRefCount(pVarname); + if( rc!=TCL_OK ) Tcl_BackgroundError(p->interp); +} + +/* +** Destructor for a TCL quota-over-limit callback. +*/ +static void tclCallbackDestructor(void *pObj){ + TclQuotaCallback *p = (TclQuotaCallback*)pObj; + if( p ){ + Tcl_DecrRefCount(p->pScript); + sqlite3_free((char *)p); + } +} + +/* +** tclcmd: sqlite3_quota_initialize NAME MAKEDEFAULT +*/ +static int test_quota_initialize( + void * clientData, + Tcl_Interp *interp, + int objc, + Tcl_Obj *CONST objv[] +){ + const char *zName; /* Name of new quota VFS */ + int makeDefault; /* True to make the new VFS the default */ + int rc; /* Value returned by quota_initialize() */ + + /* Process arguments */ + if( objc!=3 ){ + Tcl_WrongNumArgs(interp, 1, objv, "NAME MAKEDEFAULT"); + return TCL_ERROR; + } + zName = Tcl_GetString(objv[1]); + if( Tcl_GetBooleanFromObj(interp, objv[2], &makeDefault) ) return TCL_ERROR; + if( zName[0]=='\0' ) zName = 0; + + /* Call sqlite3_quota_initialize() */ + rc = sqlite3_quota_initialize(zName, makeDefault); + Tcl_SetResult(interp, (char *)sqlite3TestErrorName(rc), TCL_STATIC); + + return TCL_OK; +} + +/* +** tclcmd: sqlite3_quota_shutdown +*/ +static int test_quota_shutdown( + void * clientData, + Tcl_Interp *interp, + int objc, + Tcl_Obj *CONST objv[] +){ + int rc; /* Value returned by quota_shutdown() */ + + if( objc!=1 ){ + Tcl_WrongNumArgs(interp, 1, objv, ""); + return TCL_ERROR; + } + + /* Call sqlite3_quota_shutdown() */ + rc = sqlite3_quota_shutdown(); + Tcl_SetResult(interp, (char *)sqlite3TestErrorName(rc), TCL_STATIC); + + return TCL_OK; +} + +/* +** tclcmd: sqlite3_quota_set PATTERN LIMIT SCRIPT +*/ +static int test_quota_set( + void * clientData, + Tcl_Interp *interp, + int objc, + Tcl_Obj *CONST objv[] +){ + const char *zPattern; /* File pattern to configure */ + sqlite3_int64 iLimit; /* Initial quota in bytes */ + Tcl_Obj *pScript; /* Tcl script to invoke to increase quota */ + int rc; /* Value returned by quota_set() */ + TclQuotaCallback *p; /* Callback object */ + int nScript; /* Length of callback script */ + void (*xDestroy)(void*); /* Optional destructor for pArg */ + void (*xCallback)(const char *, sqlite3_int64 *, sqlite3_int64, void *); + + /* Process arguments */ + if( objc!=4 ){ + Tcl_WrongNumArgs(interp, 1, objv, "PATTERN LIMIT SCRIPT"); + return TCL_ERROR; + } + zPattern = Tcl_GetString(objv[1]); + if( Tcl_GetWideIntFromObj(interp, objv[2], &iLimit) ) return TCL_ERROR; + pScript = objv[3]; + Tcl_GetStringFromObj(pScript, &nScript); + + if( nScript>0 ){ + /* Allocate a TclQuotaCallback object */ + p = (TclQuotaCallback *)sqlite3_malloc(sizeof(TclQuotaCallback)); + if( !p ){ + Tcl_SetResult(interp, (char *)"SQLITE_NOMEM", TCL_STATIC); + return TCL_OK; + } + memset(p, 0, sizeof(TclQuotaCallback)); + p->interp = interp; + Tcl_IncrRefCount(pScript); + p->pScript = pScript; + xDestroy = tclCallbackDestructor; + xCallback = tclQuotaCallback; + }else{ + p = 0; + xDestroy = 0; + xCallback = 0; + } + + /* Invoke sqlite3_quota_set() */ + rc = sqlite3_quota_set(zPattern, iLimit, xCallback, (void*)p, xDestroy); + + Tcl_SetResult(interp, (char *)sqlite3TestErrorName(rc), TCL_STATIC); + return TCL_OK; +} + +/* +** tclcmd: sqlite3_quota_file FILENAME +*/ +static int test_quota_file( + void * clientData, + Tcl_Interp *interp, + int objc, + Tcl_Obj *CONST objv[] +){ + const char *zFilename; /* File pattern to configure */ + int rc; /* Value returned by quota_file() */ + + /* Process arguments */ + if( objc!=2 ){ + Tcl_WrongNumArgs(interp, 1, objv, "FILENAME"); + return TCL_ERROR; + } + zFilename = Tcl_GetString(objv[1]); + + /* Invoke sqlite3_quota_file() */ + rc = sqlite3_quota_file(zFilename); + + Tcl_SetResult(interp, (char *)sqlite3TestErrorName(rc), TCL_STATIC); + return TCL_OK; +} + +/* +** tclcmd: sqlite3_quota_dump +*/ +static int test_quota_dump( + void * clientData, + Tcl_Interp *interp, + int objc, + Tcl_Obj *CONST objv[] +){ + Tcl_Obj *pResult; + Tcl_Obj *pGroupTerm; + Tcl_Obj *pFileTerm; + quotaGroup *pGroup; + quotaFile *pFile; + + pResult = Tcl_NewObj(); + quotaEnter(); + for(pGroup=gQuota.pGroup; pGroup; pGroup=pGroup->pNext){ + pGroupTerm = Tcl_NewObj(); + Tcl_ListObjAppendElement(interp, pGroupTerm, + Tcl_NewStringObj(pGroup->zPattern, -1)); + Tcl_ListObjAppendElement(interp, pGroupTerm, + Tcl_NewWideIntObj(pGroup->iLimit)); + Tcl_ListObjAppendElement(interp, pGroupTerm, + Tcl_NewWideIntObj(pGroup->iSize)); + for(pFile=pGroup->pFiles; pFile; pFile=pFile->pNext){ + pFileTerm = Tcl_NewObj(); + Tcl_ListObjAppendElement(interp, pFileTerm, + Tcl_NewStringObj(pFile->zFilename, -1)); + Tcl_ListObjAppendElement(interp, pFileTerm, + Tcl_NewWideIntObj(pFile->iSize)); + Tcl_ListObjAppendElement(interp, pFileTerm, + Tcl_NewWideIntObj(pFile->nRef)); + Tcl_ListObjAppendElement(interp, pFileTerm, + Tcl_NewWideIntObj(pFile->deleteOnClose)); + Tcl_ListObjAppendElement(interp, pGroupTerm, pFileTerm); + } + Tcl_ListObjAppendElement(interp, pResult, pGroupTerm); + } + quotaLeave(); + Tcl_SetObjResult(interp, pResult); + return TCL_OK; +} + +/* +** This routine registers the custom TCL commands defined in this +** module. This should be the only procedure visible from outside +** of this module. +*/ +int Sqlitequota_Init(Tcl_Interp *interp){ + static struct { + char *zName; + Tcl_ObjCmdProc *xProc; + } aCmd[] = { + { "sqlite3_quota_initialize", test_quota_initialize }, + { "sqlite3_quota_shutdown", test_quota_shutdown }, + { "sqlite3_quota_set", test_quota_set }, + { "sqlite3_quota_file", test_quota_file }, + { "sqlite3_quota_dump", test_quota_dump }, + }; + int i; + + for(i=0; i<sizeof(aCmd)/sizeof(aCmd[0]); i++){ + Tcl_CreateObjCommand(interp, aCmd[i].zName, aCmd[i].xProc, 0, 0); + } + + return TCL_OK; +} +#endif |