/*
** 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 */
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); }
/* If the reference count and threshold for a quotaGroup are both
** zero, then destroy the quotaGroup.
*/
static void quotaGroupDeref(quotaGroup *pGroup){
if( pGroup->pFiles==0 && pGroup->iLimit==0 ){
*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];
}
/************************* 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 ){
for(pFile=pGroup->pFiles; pFile && strcmp(pFile->zFilename, zName);
pFile=pFile->pNext){}
if( pFile==0 ){
int nName = strlen(zName);
pFile = 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->nRef++;
pQuotaOpen->pFile = pFile;
if( pSubOpen->pMethods->iVersion==1 ){
pQuotaOpen->base.pMethods = &gQuota.sIoMethodsV1;
}else{
pQuotaOpen->base.pMethods = &gQuota.sIoMethodsV2;
}
}
}
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;
pGroup->iSize -= pFile->iSize;
if( pFile->pNext ) pFile->pNext->ppPrev = pFile->ppPrev;
*pFile->ppPrev = pFile->pNext;
quotaGroupDeref(pGroup);
sqlite3_free(pFile);
}
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.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 one 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( pGroup->pFiles ) return SQLITE_MISUSE;
}
while( gQuota.pGroup ){
pGroup = gQuota.pGroup;
gQuota.pGroup = pGroup->pNext;
pGroup->iLimit = 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 = 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;
}
/***************************** 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_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, 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_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