ds@1952:  /*
ds@1952: ** 2005 November 29
ds@1952: **
ds@1952: ** The author disclaims copyright to this source code.  In place of
ds@1952: ** a legal notice, here is a blessing:
ds@1952: **
ds@1952: **    May you do good and not evil.
ds@1952: **    May you find forgiveness for yourself and forgive others.
ds@1952: **    May you share freely, never taking more than you give.
ds@1952: **
ds@1952: ******************************************************************************
ds@1952: **
ds@1952: ** This file contains OS interface code that is common to all
ds@1952: ** architectures.
ds@1952: */
ds@1952: #define _SQLITE_OS_C_ 1
ds@1952: #include "sqliteInt.h"
ds@1952: #undef _SQLITE_OS_C_
ds@1952: 
ds@1952: /*
ds@1952: ** The default SQLite sqlite3_vfs implementations do not allocate
ds@1952: ** memory (actually, os_unix.c allocates a small amount of memory
ds@1952: ** from within OsOpen()), but some third-party implementations may.
ds@1952: ** So we test the effects of a malloc() failing and the sqlite3OsXXX()
ds@1952: ** function returning SQLITE_IOERR_NOMEM using the DO_OS_MALLOC_TEST macro.
ds@1952: **
ds@1952: ** The following functions are instrumented for malloc() failure 
ds@1952: ** testing:
ds@1952: **
ds@1952: **     sqlite3OsOpen()
ds@1952: **     sqlite3OsRead()
ds@1952: **     sqlite3OsWrite()
ds@1952: **     sqlite3OsSync()
ds@1952: **     sqlite3OsLock()
ds@1952: **
ds@1952: */
ds@1952: #ifdef SQLITE_TEST
ds@1952:   #define DO_OS_MALLOC_TEST if (1) {            \
ds@1952:     void *pTstAlloc = sqlite3_malloc(10);       \
ds@1952:     if (!pTstAlloc) return SQLITE_IOERR_NOMEM;  \
ds@1952:     sqlite3_free(pTstAlloc);                    \
ds@1952:   }
ds@1952: #else
ds@1952:   #define DO_OS_MALLOC_TEST
ds@1952: #endif
ds@1952: 
ds@1952: /*
ds@1952: ** The following routines are convenience wrappers around methods
ds@1952: ** of the sqlite3_file object.  This is mostly just syntactic sugar. All
ds@1952: ** of this would be completely automatic if SQLite were coded using
ds@1952: ** C++ instead of plain old C.
ds@1952: */
ds@1952: int sqlite3OsClose(sqlite3_file *pId){
ds@1952:   int rc = SQLITE_OK;
ds@1952:   if( pId->pMethods ){
ds@1952:     rc = pId->pMethods->xClose(pId);
ds@1952:     pId->pMethods = 0;
ds@1952:   }
ds@1952:   return rc;
ds@1952: }
ds@1952: int sqlite3OsRead(sqlite3_file *id, void *pBuf, int amt, i64 offset){
ds@1952:   DO_OS_MALLOC_TEST;
ds@1952:   return id->pMethods->xRead(id, pBuf, amt, offset);
ds@1952: }
ds@1952: int sqlite3OsWrite(sqlite3_file *id, const void *pBuf, int amt, i64 offset){
ds@1952:   DO_OS_MALLOC_TEST;
ds@1952:   return id->pMethods->xWrite(id, pBuf, amt, offset);
ds@1952: }
ds@1952: int sqlite3OsTruncate(sqlite3_file *id, i64 size){
ds@1952:   return id->pMethods->xTruncate(id, size);
ds@1952: }
ds@1952: int sqlite3OsSync(sqlite3_file *id, int flags){
ds@1952:   DO_OS_MALLOC_TEST;
ds@1952:   return id->pMethods->xSync(id, flags);
ds@1952: }
ds@1952: int sqlite3OsFileSize(sqlite3_file *id, i64 *pSize){
ds@1952:   return id->pMethods->xFileSize(id, pSize);
ds@1952: }
ds@1952: int sqlite3OsLock(sqlite3_file *id, int lockType){
ds@1952:   DO_OS_MALLOC_TEST;
ds@1952:   return id->pMethods->xLock(id, lockType);
ds@1952: }
ds@1952: int sqlite3OsUnlock(sqlite3_file *id, int lockType){
ds@1952:   return id->pMethods->xUnlock(id, lockType);
ds@1952: }
ds@1952: int sqlite3OsCheckReservedLock(sqlite3_file *id){
ds@1952:   return id->pMethods->xCheckReservedLock(id);
ds@1952: }
ds@1952: int sqlite3OsFileControl(sqlite3_file *id, int op, void *pArg){
ds@1952:   return id->pMethods->xFileControl(id,op,pArg);
ds@1952: }
ds@1952: 
ds@1952: #ifdef SQLITE_TEST
ds@1952:   /* The following two variables are used to override the values returned
ds@1952:   ** by the xSectorSize() and xDeviceCharacteristics() vfs methods for
ds@1952:   ** testing purposes. They are usually set by a test command implemented
ds@1952:   ** in test6.c.
ds@1952:   */
ds@1952:   int sqlite3_test_sector_size = 0;
ds@1952:   int sqlite3_test_device_characteristics = 0;
ds@1952:   int sqlite3OsDeviceCharacteristics(sqlite3_file *id){
ds@1952:     int dc = id->pMethods->xDeviceCharacteristics(id);
ds@1952:     return dc | sqlite3_test_device_characteristics;
ds@1952:   }
ds@1952:   int sqlite3OsSectorSize(sqlite3_file *id){
ds@1952:     if( sqlite3_test_sector_size==0 ){
ds@1952:       int (*xSectorSize)(sqlite3_file*) = id->pMethods->xSectorSize;
ds@1952:       return (xSectorSize ? xSectorSize(id) : SQLITE_DEFAULT_SECTOR_SIZE);
ds@1952:     }
ds@1952:     return sqlite3_test_sector_size;
ds@1952:   }
ds@1952: #else
ds@1952:   int sqlite3OsSectorSize(sqlite3_file *id){
ds@1952:     int (*xSectorSize)(sqlite3_file*) = id->pMethods->xSectorSize;
ds@1952:     return (xSectorSize ? xSectorSize(id) : SQLITE_DEFAULT_SECTOR_SIZE);
ds@1952:   }
ds@1952:   int sqlite3OsDeviceCharacteristics(sqlite3_file *id){
ds@1952:     return id->pMethods->xDeviceCharacteristics(id);
ds@1952:   }
ds@1952: #endif
ds@1952: 
ds@1952: /*
ds@1952: ** The next group of routines are convenience wrappers around the
ds@1952: ** VFS methods.
ds@1952: */
ds@1952: int sqlite3OsOpen(
ds@1952:   sqlite3_vfs *pVfs, 
ds@1952:   const char *zPath, 
ds@1952:   sqlite3_file *pFile, 
ds@1952:   int flags, 
ds@1952:   int *pFlagsOut
ds@1952: ){
ds@1952:   DO_OS_MALLOC_TEST;
ds@1952:   return pVfs->xOpen(pVfs, zPath, pFile, flags, pFlagsOut);
ds@1952: }
ds@1952: int sqlite3OsDelete(sqlite3_vfs *pVfs, const char *zPath, int dirSync){
ds@1952:   return pVfs->xDelete(pVfs, zPath, dirSync);
ds@1952: }
ds@1952: int sqlite3OsAccess(sqlite3_vfs *pVfs, const char *zPath, int flags){
ds@1952:   return pVfs->xAccess(pVfs, zPath, flags);
ds@1952: }
ds@1952: int sqlite3OsGetTempname(sqlite3_vfs *pVfs, int nBufOut, char *zBufOut){
ds@1952:   return pVfs->xGetTempname(pVfs, nBufOut, zBufOut);
ds@1952: }
ds@1952: int sqlite3OsFullPathname(
ds@1952:   sqlite3_vfs *pVfs, 
ds@1952:   const char *zPath, 
ds@1952:   int nPathOut, 
ds@1952:   char *zPathOut
ds@1952: ){
ds@1952:   return pVfs->xFullPathname(pVfs, zPath, nPathOut, zPathOut);
ds@1952: }
ds@1952: void *sqlite3OsDlOpen(sqlite3_vfs *pVfs, const char *zPath){
ds@1952:   return pVfs->xDlOpen(pVfs, zPath);
ds@1952: }
ds@1952: void sqlite3OsDlError(sqlite3_vfs *pVfs, int nByte, char *zBufOut){
ds@1952:   pVfs->xDlError(pVfs, nByte, zBufOut);
ds@1952: }
ds@1952: void *sqlite3OsDlSym(sqlite3_vfs *pVfs, void *pHandle, const char *zSymbol){
ds@1952:   return pVfs->xDlSym(pVfs, pHandle, zSymbol);
ds@1952: }
ds@1952: void sqlite3OsDlClose(sqlite3_vfs *pVfs, void *pHandle){
ds@1952:   pVfs->xDlClose(pVfs, pHandle);
ds@1952: }
ds@1952: int sqlite3OsRandomness(sqlite3_vfs *pVfs, int nByte, char *zBufOut){
ds@1952:   return pVfs->xRandomness(pVfs, nByte, zBufOut);
ds@1952: }
ds@1952: int sqlite3OsSleep(sqlite3_vfs *pVfs, int nMicro){
ds@1952:   return pVfs->xSleep(pVfs, nMicro);
ds@1952: }
ds@1952: int sqlite3OsCurrentTime(sqlite3_vfs *pVfs, double *pTimeOut){
ds@1952:   return pVfs->xCurrentTime(pVfs, pTimeOut);
ds@1952: }
ds@1952: 
ds@1952: int sqlite3OsOpenMalloc(
ds@1952:   sqlite3_vfs *pVfs, 
ds@1952:   const char *zFile, 
ds@1952:   sqlite3_file **ppFile, 
ds@1952:   int flags,
ds@1952:   int *pOutFlags
ds@1952: ){
ds@1952:   int rc = SQLITE_NOMEM;
ds@1952:   sqlite3_file *pFile;
ds@1952:   pFile = (sqlite3_file *)sqlite3_malloc(pVfs->szOsFile);
ds@1952:   if( pFile ){
ds@1952:     rc = sqlite3OsOpen(pVfs, zFile, pFile, flags, pOutFlags);
ds@1952:     if( rc!=SQLITE_OK ){
ds@1952:       sqlite3_free(pFile);
ds@1952:     }else{
ds@1952:       *ppFile = pFile;
ds@1952:     }
ds@1952:   }
ds@1952:   return rc;
ds@1952: }
ds@1952: int sqlite3OsCloseFree(sqlite3_file *pFile){
ds@1952:   int rc = SQLITE_OK;
ds@1952:   if( pFile ){
ds@1952:     rc = sqlite3OsClose(pFile);
ds@1952:     sqlite3_free(pFile);
ds@1952:   }
ds@1952:   return rc;
ds@1952: }
ds@1952: 
ds@1952: /*
ds@1952: ** The list of all registered VFS implementations.  This list is
ds@1952: ** initialized to the single VFS returned by sqlite3OsDefaultVfs()
ds@1952: ** upon the first call to sqlite3_vfs_find().
ds@1952: */
ds@1952: static sqlite3_vfs *vfsList = 0;
ds@1952: 
ds@1952: /*
ds@1952: ** Locate a VFS by name.  If no name is given, simply return the
ds@1952: ** first VFS on the list.
ds@1952: */
ds@1952: sqlite3_vfs *sqlite3_vfs_find(const char *zVfs){
ds@1952:   sqlite3_mutex *mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);
ds@1952:   sqlite3_vfs *pVfs;
ds@1952:   static int isInit = 0;
ds@1952:   sqlite3_mutex_enter(mutex);
ds@1952:   if( !isInit ){
ds@1952:     vfsList = sqlite3OsDefaultVfs();
ds@1952:     isInit = 1;
ds@1952:   }
ds@1952:   for(pVfs = vfsList; pVfs; pVfs=pVfs->pNext){
ds@1952:     if( zVfs==0 ) break;
ds@1952:     if( strcmp(zVfs, pVfs->zName)==0 ) break;
ds@1952:   }
ds@1952:   sqlite3_mutex_leave(mutex);
ds@1952:   return pVfs;
ds@1952: }
ds@1952: 
ds@1952: /*
ds@1952: ** Unlink a VFS from the linked list
ds@1952: */
ds@1952: static void vfsUnlink(sqlite3_vfs *pVfs){
ds@1952:   assert( sqlite3_mutex_held(sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER)) );
ds@1952:   if( vfsList==pVfs ){
ds@1952:     vfsList = pVfs->pNext;
ds@1952:   }else{
ds@1952:     sqlite3_vfs *p = vfsList;
ds@1952:     while( p->pNext && p->pNext!=pVfs ){
ds@1952:       p = p->pNext;
ds@1952:     }
ds@1952:     if( p->pNext==pVfs ){
ds@1952:       p->pNext = pVfs->pNext;
ds@1952:     }
ds@1952:   }
ds@1952: }
ds@1952: 
ds@1952: /*
ds@1952: ** Register a VFS with the system.  It is harmless to register the same
ds@1952: ** VFS multiple times.  The new VFS becomes the default if makeDflt is
ds@1952: ** true.
ds@1952: */
ds@1952: int sqlite3_vfs_register(sqlite3_vfs *pVfs, int makeDflt){
ds@1952:   sqlite3_mutex *mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);
ds@1952:   sqlite3_vfs_find(0);  /* Make sure we are initialized */
ds@1952:   sqlite3_mutex_enter(mutex);
ds@1952:   vfsUnlink(pVfs);
ds@1952:   if( makeDflt || vfsList==0 ){
ds@1952:     pVfs->pNext = vfsList;
ds@1952:     vfsList = pVfs;
ds@1952:   }else{
ds@1952:     pVfs->pNext = vfsList->pNext;
ds@1952:     vfsList->pNext = pVfs;
ds@1952:   }
ds@1952:   assert(vfsList);
ds@1952:   sqlite3_mutex_leave(mutex);
ds@1952:   return SQLITE_OK;
ds@1952: }
ds@1952: 
ds@1952: /*
ds@1952: ** Unregister a VFS so that it is no longer accessible.
ds@1952: */
ds@1952: int sqlite3_vfs_unregister(sqlite3_vfs *pVfs){
ds@1952:   sqlite3_mutex *mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);
ds@1952:   sqlite3_mutex_enter(mutex);
ds@1952:   vfsUnlink(pVfs);
ds@1952:   assert(vfsList);
ds@1952:   sqlite3_mutex_leave(mutex);
ds@1952:   return SQLITE_OK;
ds@1952: }