*/
#include "os_common.h"
+/* Forward references */
+typedef struct os2File os2File; /* The file structure */
+typedef struct os2ShmNode os2ShmNode; /* A shared descritive memory node */
+typedef struct os2ShmLink os2ShmLink; /* A connection to shared-memory */
+
/*
** The os2File structure is subclass of sqlite3_file specific for the OS/2
** protability layer.
*/
-typedef struct os2File os2File;
struct os2File {
const sqlite3_io_methods *pMethod; /* Always the first entry */
HFILE h; /* Handle for accessing the file */
- char* pathToDel; /* Name of file to delete on close, NULL if not */
- unsigned char locktype; /* Type of lock currently held on this file */
+ int flags; /* Flags provided to os2Open() */
+ int locktype; /* Type of lock currently held on this file */
+ int szChunk; /* Chunk size configured by FCNTL_CHUNK_SIZE */
+ char *zFullPathCp; /* Full path name of this file */
+ os2ShmLink *pShmLink; /* Instance of shared memory on this file */
};
#define LOCK_TIMEOUT 10L /* the default locking timeout */
+/*
+** Missing from some versions of the OS/2 toolkit -
+** used to allocate from high memory if possible
+*/
+#ifndef OBJ_ANY
+# define OBJ_ANY 0x00000400
+#endif
+
/*****************************************************************************
** The next group of routines implement the I/O methods specified
** by the sqlite3_io_methods object.
** Close a file.
*/
static int os2Close( sqlite3_file *id ){
- APIRET rc = NO_ERROR;
- os2File *pFile;
- if( id && (pFile = (os2File*)id) != 0 ){
- OSTRACE(( "CLOSE %d\n", pFile->h ));
- rc = DosClose( pFile->h );
- pFile->locktype = NO_LOCK;
- if( pFile->pathToDel != NULL ){
- rc = DosForceDelete( (PSZ)pFile->pathToDel );
- free( pFile->pathToDel );
- pFile->pathToDel = NULL;
- }
- id = 0;
- OpenCounter( -1 );
- }
+ APIRET rc;
+ os2File *pFile = (os2File*)id;
+
+ assert( id!=0 );
+ OSTRACE(( "CLOSE %d (%s)\n", pFile->h, pFile->zFullPathCp ));
+
+ rc = DosClose( pFile->h );
+ if( pFile->flags & SQLITE_OPEN_DELETEONCLOSE )
+ DosForceDelete( (PSZ)pFile->zFullPathCp );
+
+ free( pFile->zFullPathCp );
+ pFile->zFullPathCp = NULL;
+ pFile->locktype = NO_LOCK;
+ pFile->h = (HFILE)-1;
+ pFile->flags = 0;
+
+ OpenCounter( -1 );
return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR;
}
** Truncate an open file to a specified size
*/
static int os2Truncate( sqlite3_file *id, i64 nByte ){
- APIRET rc = NO_ERROR;
+ APIRET rc;
os2File *pFile = (os2File*)id;
+ assert( id!=0 );
OSTRACE(( "TRUNCATE %d %lld\n", pFile->h, nByte ));
SimulateIOError( return SQLITE_IOERR_TRUNCATE );
+
+ /* If the user has configured a chunk-size for this file, truncate the
+ ** file so that it consists of an integer number of chunks (i.e. the
+ ** actual file size after the operation may be larger than the requested
+ ** size).
+ */
+ if( pFile->szChunk ){
+ nByte = ((nByte + pFile->szChunk - 1)/pFile->szChunk) * pFile->szChunk;
+ }
+
rc = DosSetFileSize( pFile->h, nByte );
return rc == NO_ERROR ? SQLITE_OK : SQLITE_IOERR_TRUNCATE;
}
((os2File*)id)->h, ((os2File*)id)->locktype ));
return SQLITE_OK;
}
+ case SQLITE_FCNTL_CHUNK_SIZE: {
+ ((os2File*)id)->szChunk = *(int*)pArg;
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_SIZE_HINT: {
+ sqlite3_int64 sz = *(sqlite3_int64*)pArg;
+ SimulateIOErrorBenign(1);
+ os2Truncate(id, sz);
+ SimulateIOErrorBenign(0);
+ return SQLITE_OK;
+ }
+ case SQLITE_FCNTL_SYNC_OMITTED: {
+ return SQLITE_OK;
+ }
}
return SQLITE_NOTFOUND;
}
** same for both.
*/
static int os2SectorSize(sqlite3_file *id){
+ UNUSED_PARAMETER(id);
return SQLITE_DEFAULT_SECTOR_SIZE;
}
** Return a vector of device characteristics.
*/
static int os2DeviceCharacteristics(sqlite3_file *id){
- return 0;
+ UNUSED_PARAMETER(id);
+ return SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN;
}
return out;
}
+
+#ifndef SQLITE_OMIT_WAL
+
+/*
+** Use main database file for interprocess locking. If un-defined
+** a separate file is created for this purpose. The file will be
+** used only to set file locks. There will be no data written to it.
+*/
+#define SQLITE_OS2_NO_WAL_LOCK_FILE
+
+#if 0
+static void _ERR_TRACE( const char *fmt, ... ) {
+ va_list ap;
+ va_start(ap, fmt);
+ vfprintf(stderr, fmt, ap);
+ fflush(stderr);
+}
+#define ERR_TRACE(rc, msg) \
+ if( (rc) != SQLITE_OK ) _ERR_TRACE msg;
+#else
+#define ERR_TRACE(rc, msg)
+#endif
+
+/*
+** Helper functions to obtain and relinquish the global mutex. The
+** global mutex is used to protect os2ShmNodeList.
+**
+** Function os2ShmMutexHeld() is used to assert() that the global mutex
+** is held when required. This function is only used as part of assert()
+** statements. e.g.
+**
+** os2ShmEnterMutex()
+** assert( os2ShmMutexHeld() );
+** os2ShmLeaveMutex()
+*/
+static void os2ShmEnterMutex(void){
+ sqlite3_mutex_enter(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
+}
+static void os2ShmLeaveMutex(void){
+ sqlite3_mutex_leave(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
+}
+#ifdef SQLITE_DEBUG
+static int os2ShmMutexHeld(void) {
+ return sqlite3_mutex_held(sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER));
+}
+int GetCurrentProcessId(void) {
+ PPIB pib;
+ DosGetInfoBlocks(NULL, &pib);
+ return (int)pib->pib_ulpid;
+}
+#endif
+
+/*
+** Object used to represent a the shared memory area for a single log file.
+** When multiple threads all reference the same log-summary, each thread has
+** its own os2File object, but they all point to a single instance of this
+** object. In other words, each log-summary is opened only once per process.
+**
+** os2ShmMutexHeld() must be true when creating or destroying
+** this object or while reading or writing the following fields:
+**
+** nRef
+** pNext
+**
+** The following fields are read-only after the object is created:
+**
+** szRegion
+** hLockFile
+** shmBaseName
+**
+** Either os2ShmNode.mutex must be held or os2ShmNode.nRef==0 and
+** os2ShmMutexHeld() is true when reading or writing any other field
+** in this structure.
+**
+*/
+struct os2ShmNode {
+ sqlite3_mutex *mutex; /* Mutex to access this object */
+ os2ShmNode *pNext; /* Next in list of all os2ShmNode objects */
+
+ int szRegion; /* Size of shared-memory regions */
+
+ int nRegion; /* Size of array apRegion */
+ void **apRegion; /* Array of pointers to shared-memory regions */
+
+ int nRef; /* Number of os2ShmLink objects pointing to this */
+ os2ShmLink *pFirst; /* First os2ShmLink object pointing to this */
+
+ HFILE hLockFile; /* File used for inter-process memory locking */
+ char shmBaseName[1]; /* Name of the memory object !!! must last !!! */
+};
+
+
+/*
+** Structure used internally by this VFS to record the state of an
+** open shared memory connection.
+**
+** The following fields are initialized when this object is created and
+** are read-only thereafter:
+**
+** os2Shm.pShmNode
+** os2Shm.id
+**
+** All other fields are read/write. The os2Shm.pShmNode->mutex must be held
+** while accessing any read/write fields.
+*/
+struct os2ShmLink {
+ os2ShmNode *pShmNode; /* The underlying os2ShmNode object */
+ os2ShmLink *pNext; /* Next os2Shm with the same os2ShmNode */
+ u32 sharedMask; /* Mask of shared locks held */
+ u32 exclMask; /* Mask of exclusive locks held */
+#ifdef SQLITE_DEBUG
+ u8 id; /* Id of this connection with its os2ShmNode */
+#endif
+};
+
+
+/*
+** A global list of all os2ShmNode objects.
+**
+** The os2ShmMutexHeld() must be true while reading or writing this list.
+*/
+static os2ShmNode *os2ShmNodeList = NULL;
+
+/*
+** Constants used for locking
+*/
+#ifdef SQLITE_OS2_NO_WAL_LOCK_FILE
+#define OS2_SHM_BASE (PENDING_BYTE + 0x10000) /* first lock byte */
+#else
+#define OS2_SHM_BASE ((22+SQLITE_SHM_NLOCK)*4) /* first lock byte */
+#endif
+
+#define OS2_SHM_DMS (OS2_SHM_BASE+SQLITE_SHM_NLOCK) /* deadman switch */
+
+/*
+** Apply advisory locks for all n bytes beginning at ofst.
+*/
+#define _SHM_UNLCK 1 /* no lock */
+#define _SHM_RDLCK 2 /* shared lock, no wait */
+#define _SHM_WRLCK 3 /* exlusive lock, no wait */
+#define _SHM_WRLCK_WAIT 4 /* exclusive lock, wait */
+static int os2ShmSystemLock(
+ os2ShmNode *pNode, /* Apply locks to this open shared-memory segment */
+ int lockType, /* _SHM_UNLCK, _SHM_RDLCK, _SHM_WRLCK or _SHM_WRLCK_WAIT */
+ int ofst, /* Offset to first byte to be locked/unlocked */
+ int nByte /* Number of bytes to lock or unlock */
+){
+ APIRET rc;
+ FILELOCK area;
+ ULONG mode, timeout;
+
+ /* Access to the os2ShmNode object is serialized by the caller */
+ assert( sqlite3_mutex_held(pNode->mutex) || pNode->nRef==0 );
+
+ mode = 1; /* shared lock */
+ timeout = 0; /* no wait */
+ area.lOffset = ofst;
+ area.lRange = nByte;
+
+ switch( lockType ) {
+ case _SHM_WRLCK_WAIT:
+ timeout = (ULONG)-1; /* wait forever */
+ case _SHM_WRLCK:
+ mode = 0; /* exclusive lock */
+ case _SHM_RDLCK:
+ rc = DosSetFileLocks(pNode->hLockFile,
+ NULL, &area, timeout, mode);
+ break;
+ /* case _SHM_UNLCK: */
+ default:
+ rc = DosSetFileLocks(pNode->hLockFile,
+ &area, NULL, 0, 0);
+ break;
+ }
+
+ OSTRACE(("SHM-LOCK %d %s %s 0x%08lx\n",
+ pNode->hLockFile,
+ rc==SQLITE_OK ? "ok" : "failed",
+ lockType==_SHM_UNLCK ? "Unlock" : "Lock",
+ rc));
+
+ ERR_TRACE(rc, ("os2ShmSystemLock: %d %s\n", rc, pNode->shmBaseName))
+
+ return ( rc == 0 ) ? SQLITE_OK : SQLITE_BUSY;
+}
+
+/*
+** Find an os2ShmNode in global list or allocate a new one, if not found.
+**
+** This is not a VFS shared-memory method; it is a utility function called
+** by VFS shared-memory methods.
+*/
+static int os2OpenSharedMemory( os2File *fd, int szRegion ) {
+ os2ShmLink *pLink;
+ os2ShmNode *pNode;
+ int cbShmName, rc = SQLITE_OK;
+ char shmName[CCHMAXPATH + 30];
+#ifndef SQLITE_OS2_NO_WAL_LOCK_FILE
+ ULONG action;
+#endif
+
+ /* We need some additional space at the end to append the region number */
+ cbShmName = sprintf(shmName, "\\SHAREMEM\\%s", fd->zFullPathCp );
+ if( cbShmName >= CCHMAXPATH-8 )
+ return SQLITE_IOERR_SHMOPEN;
+
+ /* Replace colon in file name to form a valid shared memory name */
+ shmName[10+1] = '!';
+
+ /* Allocate link object (we free it later in case of failure) */
+ pLink = sqlite3_malloc( sizeof(*pLink) );
+ if( !pLink )
+ return SQLITE_NOMEM;
+
+ /* Access node list */
+ os2ShmEnterMutex();
+
+ /* Find node by it's shared memory base name */
+ for( pNode = os2ShmNodeList;
+ pNode && stricmp(shmName, pNode->shmBaseName) != 0;
+ pNode = pNode->pNext ) ;
+
+ /* Not found: allocate a new node */
+ if( !pNode ) {
+ pNode = sqlite3_malloc( sizeof(*pNode) + cbShmName );
+ if( pNode ) {
+ memset(pNode, 0, sizeof(*pNode) );
+ pNode->szRegion = szRegion;
+ pNode->hLockFile = (HFILE)-1;
+ strcpy(pNode->shmBaseName, shmName);
+
+#ifdef SQLITE_OS2_NO_WAL_LOCK_FILE
+ if( DosDupHandle(fd->h, &pNode->hLockFile) != 0 ) {
+#else
+ sprintf(shmName, "%s-lck", fd->zFullPathCp);
+ if( DosOpen((PSZ)shmName, &pNode->hLockFile, &action, 0, FILE_NORMAL,
+ OPEN_ACTION_OPEN_IF_EXISTS | OPEN_ACTION_CREATE_IF_NEW,
+ OPEN_ACCESS_READWRITE | OPEN_SHARE_DENYNONE |
+ OPEN_FLAGS_NOINHERIT | OPEN_FLAGS_FAIL_ON_ERROR,
+ NULL) != 0 ) {
+#endif
+ sqlite3_free(pNode);
+ rc = SQLITE_IOERR;
+ } else {
+ pNode->mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_FAST);
+ if( !pNode->mutex ) {
+ sqlite3_free(pNode);
+ rc = SQLITE_NOMEM;
+ }
+ }
+ } else {
+ rc = SQLITE_NOMEM;
+ }
+
+ if( rc == SQLITE_OK ) {
+ pNode->pNext = os2ShmNodeList;
+ os2ShmNodeList = pNode;
+ } else {
+ pNode = NULL;
+ }
+ } else if( pNode->szRegion != szRegion ) {
+ rc = SQLITE_IOERR_SHMSIZE;
+ pNode = NULL;
+ }
+
+ if( pNode ) {
+ sqlite3_mutex_enter(pNode->mutex);
+
+ memset(pLink, 0, sizeof(*pLink));
+
+ pLink->pShmNode = pNode;
+ pLink->pNext = pNode->pFirst;
+ pNode->pFirst = pLink;
+ pNode->nRef++;
+
+ fd->pShmLink = pLink;
+
+ sqlite3_mutex_leave(pNode->mutex);
+
+ } else {
+ /* Error occured. Free our link object. */
+ sqlite3_free(pLink);
+ }
+
+ os2ShmLeaveMutex();
+
+ ERR_TRACE(rc, ("os2OpenSharedMemory: %d %s\n", rc, fd->zFullPathCp))
+
+ return rc;
+}
+
+/*
+** Purge the os2ShmNodeList list of all entries with nRef==0.
+**
+** This is not a VFS shared-memory method; it is a utility function called
+** by VFS shared-memory methods.
+*/
+static void os2PurgeShmNodes( int deleteFlag ) {
+ os2ShmNode *pNode;
+ os2ShmNode **ppNode;
+
+ os2ShmEnterMutex();
+
+ ppNode = &os2ShmNodeList;
+
+ while( *ppNode ) {
+ pNode = *ppNode;
+
+ if( pNode->nRef == 0 ) {
+ *ppNode = pNode->pNext;
+
+ if( pNode->apRegion ) {
+ /* Prevent other processes from resizing the shared memory */
+ os2ShmSystemLock(pNode, _SHM_WRLCK_WAIT, OS2_SHM_DMS, 1);
+
+ while( pNode->nRegion-- ) {
+#ifdef SQLITE_DEBUG
+ int rc =
+#endif
+ DosFreeMem(pNode->apRegion[pNode->nRegion]);
+
+ OSTRACE(("SHM-PURGE pid-%d unmap region=%d %s\n",
+ (int)GetCurrentProcessId(), pNode->nRegion,
+ rc == 0 ? "ok" : "failed"));
+ }
+
+ /* Allow other processes to resize the shared memory */
+ os2ShmSystemLock(pNode, _SHM_UNLCK, OS2_SHM_DMS, 1);
+
+ sqlite3_free(pNode->apRegion);
+ }
+
+ DosClose(pNode->hLockFile);
+
+#ifndef SQLITE_OS2_NO_WAL_LOCK_FILE
+ if( deleteFlag ) {
+ char fileName[CCHMAXPATH];
+ /* Skip "\\SHAREMEM\\" */
+ sprintf(fileName, "%s-lck", pNode->shmBaseName + 10);
+ /* restore colon */
+ fileName[1] = ':';
+
+ DosForceDelete(fileName);
+ }
+#endif
+
+ sqlite3_mutex_free(pNode->mutex);
+
+ sqlite3_free(pNode);
+
+ } else {
+ ppNode = &pNode->pNext;
+ }
+ }
+
+ os2ShmLeaveMutex();
+}
+
+/*
+** This function is called to obtain a pointer to region iRegion of the
+** shared-memory associated with the database file id. Shared-memory regions
+** are numbered starting from zero. Each shared-memory region is szRegion
+** bytes in size.
+**
+** If an error occurs, an error code is returned and *pp is set to NULL.
+**
+** Otherwise, if the bExtend parameter is 0 and the requested shared-memory
+** region has not been allocated (by any client, including one running in a
+** separate process), then *pp is set to NULL and SQLITE_OK returned. If
+** bExtend is non-zero and the requested shared-memory region has not yet
+** been allocated, it is allocated by this function.
+**
+** If the shared-memory region has already been allocated or is allocated by
+** this call as described above, then it is mapped into this processes
+** address space (if it is not already), *pp is set to point to the mapped
+** memory and SQLITE_OK returned.
+*/
+static int os2ShmMap(
+ sqlite3_file *id, /* Handle open on database file */
+ int iRegion, /* Region to retrieve */
+ int szRegion, /* Size of regions */
+ int bExtend, /* True to extend block if necessary */
+ void volatile **pp /* OUT: Mapped memory */
+){
+ PVOID pvTemp;
+ void **apRegion;
+ os2ShmNode *pNode;
+ int n, rc = SQLITE_OK;
+ char shmName[CCHMAXPATH];
+ os2File *pFile = (os2File*)id;
+
+ *pp = NULL;
+
+ if( !pFile->pShmLink )
+ rc = os2OpenSharedMemory( pFile, szRegion );
+
+ if( rc == SQLITE_OK ) {
+ pNode = pFile->pShmLink->pShmNode ;
+
+ sqlite3_mutex_enter(pNode->mutex);
+
+ assert( szRegion==pNode->szRegion );
+
+ /* Unmapped region ? */
+ if( iRegion >= pNode->nRegion ) {
+ /* Prevent other processes from resizing the shared memory */
+ os2ShmSystemLock(pNode, _SHM_WRLCK_WAIT, OS2_SHM_DMS, 1);
+
+ apRegion = sqlite3_realloc(
+ pNode->apRegion, (iRegion + 1) * sizeof(apRegion[0]));
+
+ if( apRegion ) {
+ pNode->apRegion = apRegion;
+
+ while( pNode->nRegion <= iRegion ) {
+ sprintf(shmName, "%s-%u",
+ pNode->shmBaseName, pNode->nRegion);
+
+ if( DosGetNamedSharedMem(&pvTemp, (PSZ)shmName,
+ PAG_READ | PAG_WRITE) != NO_ERROR ) {
+ if( !bExtend )
+ break;
+
+ if( DosAllocSharedMem(&pvTemp, (PSZ)shmName, szRegion,
+ PAG_READ | PAG_WRITE | PAG_COMMIT | OBJ_ANY) != NO_ERROR &&
+ DosAllocSharedMem(&pvTemp, (PSZ)shmName, szRegion,
+ PAG_READ | PAG_WRITE | PAG_COMMIT) != NO_ERROR ) {
+ rc = SQLITE_NOMEM;
+ break;
+ }
+ }
+
+ apRegion[pNode->nRegion++] = pvTemp;
+ }
+
+ /* zero out remaining entries */
+ for( n = pNode->nRegion; n <= iRegion; n++ )
+ pNode->apRegion[n] = NULL;
+
+ /* Return this region (maybe zero) */
+ *pp = pNode->apRegion[iRegion];
+ } else {
+ rc = SQLITE_NOMEM;
+ }
+
+ /* Allow other processes to resize the shared memory */
+ os2ShmSystemLock(pNode, _SHM_UNLCK, OS2_SHM_DMS, 1);
+
+ } else {
+ /* Region has been mapped previously */
+ *pp = pNode->apRegion[iRegion];
+ }
+
+ sqlite3_mutex_leave(pNode->mutex);
+ }
+
+ ERR_TRACE(rc, ("os2ShmMap: %s iRgn = %d, szRgn = %d, bExt = %d : %d\n",
+ pFile->zFullPathCp, iRegion, szRegion, bExtend, rc))
+
+ return rc;
+}
+
+/*
+** Close a connection to shared-memory. Delete the underlying
+** storage if deleteFlag is true.
+**
+** If there is no shared memory associated with the connection then this
+** routine is a harmless no-op.
+*/
+static int os2ShmUnmap(
+ sqlite3_file *id, /* The underlying database file */
+ int deleteFlag /* Delete shared-memory if true */
+){
+ os2File *pFile = (os2File*)id;
+ os2ShmLink *pLink = pFile->pShmLink;
+
+ if( pLink ) {
+ int nRef = -1;
+ os2ShmLink **ppLink;
+ os2ShmNode *pNode = pLink->pShmNode;
+
+ sqlite3_mutex_enter(pNode->mutex);
+
+ for( ppLink = &pNode->pFirst;
+ *ppLink && *ppLink != pLink;
+ ppLink = &(*ppLink)->pNext ) ;
+
+ assert(*ppLink);
+
+ if( *ppLink ) {
+ *ppLink = pLink->pNext;
+ nRef = --pNode->nRef;
+ } else {
+ ERR_TRACE(1, ("os2ShmUnmap: link not found ! %s\n",
+ pNode->shmBaseName))
+ }
+
+ pFile->pShmLink = NULL;
+ sqlite3_free(pLink);
+
+ sqlite3_mutex_leave(pNode->mutex);
+
+ if( nRef == 0 )
+ os2PurgeShmNodes( deleteFlag );
+ }
+
+ return SQLITE_OK;
+}
+
+/*
+** Change the lock state for a shared-memory segment.
+**
+** Note that the relationship between SHAREd and EXCLUSIVE locks is a little
+** different here than in posix. In xShmLock(), one can go from unlocked
+** to shared and back or from unlocked to exclusive and back. But one may
+** not go from shared to exclusive or from exclusive to shared.
+*/
+static int os2ShmLock(
+ sqlite3_file *id, /* 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 */
+){
+ u32 mask; /* Mask of locks to take or release */
+ int rc = SQLITE_OK; /* Result code */
+ os2File *pFile = (os2File*)id;
+ os2ShmLink *p = pFile->pShmLink; /* The shared memory being locked */
+ os2ShmLink *pX; /* For looping over all siblings */
+ os2ShmNode *pShmNode = p->pShmNode; /* Our node */
+
+ assert( ofst>=0 && ofst+n<=SQLITE_SHM_NLOCK );
+ assert( n>=1 );
+ assert( flags==(SQLITE_SHM_LOCK | SQLITE_SHM_SHARED)
+ || flags==(SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE)
+ || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED)
+ || flags==(SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE) );
+ assert( n==1 || (flags & SQLITE_SHM_EXCLUSIVE)!=0 );
+
+ mask = (u32)((1U<<(ofst+n)) - (1U<<ofst));
+ assert( n>1 || mask==(1<<ofst) );
+
+
+ sqlite3_mutex_enter(pShmNode->mutex);
+
+ if( flags & SQLITE_SHM_UNLOCK ){
+ u32 allMask = 0; /* Mask of locks held by siblings */
+
+ /* See if any siblings hold this same lock */
+ for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+ if( pX==p ) continue;
+ assert( (pX->exclMask & (p->exclMask|p->sharedMask))==0 );
+ allMask |= pX->sharedMask;
+ }
+
+ /* Unlock the system-level locks */
+ if( (mask & allMask)==0 ){
+ rc = os2ShmSystemLock(pShmNode, _SHM_UNLCK, ofst+OS2_SHM_BASE, n);
+ }else{
+ rc = SQLITE_OK;
+ }
+
+ /* Undo the local locks */
+ if( rc==SQLITE_OK ){
+ p->exclMask &= ~mask;
+ p->sharedMask &= ~mask;
+ }
+ }else if( flags & SQLITE_SHM_SHARED ){
+ u32 allShared = 0; /* Union of locks held by connections other than "p" */
+
+ /* Find out which shared locks are already held by sibling connections.
+ ** If any sibling already holds an exclusive lock, go ahead and return
+ ** SQLITE_BUSY.
+ */
+ for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+ if( (pX->exclMask & mask)!=0 ){
+ rc = SQLITE_BUSY;
+ break;
+ }
+ allShared |= pX->sharedMask;
+ }
+
+ /* Get shared locks at the system level, if necessary */
+ if( rc==SQLITE_OK ){
+ if( (allShared & mask)==0 ){
+ rc = os2ShmSystemLock(pShmNode, _SHM_RDLCK, ofst+OS2_SHM_BASE, n);
+ }else{
+ rc = SQLITE_OK;
+ }
+ }
+
+ /* Get the local shared locks */
+ if( rc==SQLITE_OK ){
+ p->sharedMask |= mask;
+ }
+ }else{
+ /* Make sure no sibling connections hold locks that will block this
+ ** lock. If any do, return SQLITE_BUSY right away.
+ */
+ for(pX=pShmNode->pFirst; pX; pX=pX->pNext){
+ if( (pX->exclMask & mask)!=0 || (pX->sharedMask & mask)!=0 ){
+ rc = SQLITE_BUSY;
+ break;
+ }
+ }
+
+ /* Get the exclusive locks at the system level. Then if successful
+ ** also mark the local connection as being locked.
+ */
+ if( rc==SQLITE_OK ){
+ rc = os2ShmSystemLock(pShmNode, _SHM_WRLCK, ofst+OS2_SHM_BASE, n);
+ if( rc==SQLITE_OK ){
+ assert( (p->sharedMask & mask)==0 );
+ p->exclMask |= mask;
+ }
+ }
+ }
+
+ sqlite3_mutex_leave(pShmNode->mutex);
+
+ OSTRACE(("SHM-LOCK shmid-%d, pid-%d got %03x,%03x %s\n",
+ p->id, (int)GetCurrentProcessId(), p->sharedMask, p->exclMask,
+ rc ? "failed" : "ok"));
+
+ ERR_TRACE(rc, ("os2ShmLock: ofst = %d, n = %d, flags = 0x%x -> %d \n",
+ ofst, n, flags, rc))
+
+ return rc;
+}
+
+/*
+** Implement a memory barrier or memory fence on shared memory.
+**
+** All loads and stores begun before the barrier must complete before
+** any load or store begun after the barrier.
+*/
+static void os2ShmBarrier(
+ sqlite3_file *id /* Database file holding the shared memory */
+){
+ UNUSED_PARAMETER(id);
+ os2ShmEnterMutex();
+ os2ShmLeaveMutex();
+}
+
+#else
+# define os2ShmMap 0
+# define os2ShmLock 0
+# define os2ShmBarrier 0
+# define os2ShmUnmap 0
+#endif /* #ifndef SQLITE_OMIT_WAL */
+
+
/*
** This vector defines all the methods that can operate on an
** sqlite3_file for os2.
*/
static const sqlite3_io_methods os2IoMethod = {
- 1, /* iVersion */
+ 2, /* iVersion */
os2Close, /* xClose */
os2Read, /* xRead */
os2Write, /* xWrite */
os2FileControl, /* xFileControl */
os2SectorSize, /* xSectorSize */
os2DeviceCharacteristics, /* xDeviceCharacteristics */
- 0, /* xShmMap */
- 0, /* xShmLock */
- 0, /* xShmBarrier */
- 0 /* xShmUnmap */
+ os2ShmMap, /* xShmMap */
+ os2ShmLock, /* xShmLock */
+ os2ShmBarrier, /* xShmBarrier */
+ os2ShmUnmap /* xShmUnmap */
};
+
/***************************************************************************
** Here ends the I/O methods that form the sqlite3_io_methods object.
**
** hold at pVfs->mxPathname characters.
*/
static int getTempname(int nBuf, char *zBuf ){
- static const unsigned char zChars[] =
+ static const char zChars[] =
"abcdefghijklmnopqrstuvwxyz"
"ABCDEFGHIJKLMNOPQRSTUVWXYZ"
"0123456789";
int i, j;
- char zTempPathBuf[3];
- PSZ zTempPath = (PSZ)&zTempPathBuf;
- if( sqlite3_temp_directory ){
- zTempPath = sqlite3_temp_directory;
- }else{
- if( DosScanEnv( (PSZ)"TEMP", &zTempPath ) ){
- if( DosScanEnv( (PSZ)"TMP", &zTempPath ) ){
- if( DosScanEnv( (PSZ)"TMPDIR", &zTempPath ) ){
- ULONG ulDriveNum = 0, ulDriveMap = 0;
- DosQueryCurrentDisk( &ulDriveNum, &ulDriveMap );
- sprintf( (char*)zTempPath, "%c:", (char)( 'A' + ulDriveNum - 1 ) );
- }
- }
- }
+ PSZ zTempPathCp;
+ char zTempPath[CCHMAXPATH];
+ ULONG ulDriveNum, ulDriveMap;
+
+ /* It's odd to simulate an io-error here, but really this is just
+ ** using the io-error infrastructure to test that SQLite handles this
+ ** function failing.
+ */
+ SimulateIOError( return SQLITE_IOERR );
+
+ if( sqlite3_temp_directory ) {
+ sqlite3_snprintf(CCHMAXPATH-30, zTempPath, "%s", sqlite3_temp_directory);
+ } else if( DosScanEnv( (PSZ)"TEMP", &zTempPathCp ) == NO_ERROR ||
+ DosScanEnv( (PSZ)"TMP", &zTempPathCp ) == NO_ERROR ||
+ DosScanEnv( (PSZ)"TMPDIR", &zTempPathCp ) == NO_ERROR ) {
+ char *zTempPathUTF = convertCpPathToUtf8( (char *)zTempPathCp );
+ sqlite3_snprintf(CCHMAXPATH-30, zTempPath, "%s", zTempPathUTF);
+ free( zTempPathUTF );
+ } else if( DosQueryCurrentDisk( &ulDriveNum, &ulDriveMap ) == NO_ERROR ) {
+ zTempPath[0] = (char)('A' + ulDriveNum - 1);
+ zTempPath[1] = ':';
+ zTempPath[2] = '\0';
+ } else {
+ zTempPath[0] = '\0';
}
+
/* Strip off a trailing slashes or backslashes, otherwise we would get *
* multiple (back)slashes which causes DosOpen() to fail. *
* Trailing spaces are not allowed, either. */
j = sqlite3Strlen30(zTempPath);
- while( j > 0 && ( zTempPath[j-1] == '\\' || zTempPath[j-1] == '/'
- || zTempPath[j-1] == ' ' ) ){
+ while( j > 0 && ( zTempPath[j-1] == '\\' || zTempPath[j-1] == '/' ||
+ zTempPath[j-1] == ' ' ) ){
j--;
}
zTempPath[j] = '\0';
- if( !sqlite3_temp_directory ){
- char *zTempPathUTF = convertCpPathToUtf8( zTempPath );
- sqlite3_snprintf( nBuf-30, zBuf,
- "%s\\"SQLITE_TEMP_FILE_PREFIX, zTempPathUTF );
- free( zTempPathUTF );
- }else{
- sqlite3_snprintf( nBuf-30, zBuf,
- "%s\\"SQLITE_TEMP_FILE_PREFIX, zTempPath );
- }
- j = sqlite3Strlen30( zBuf );
+
+ /* We use 20 bytes to randomize the name */
+ sqlite3_snprintf(nBuf-22, zBuf,
+ "%s\\"SQLITE_TEMP_FILE_PREFIX, zTempPath);
+ j = sqlite3Strlen30(zBuf);
sqlite3_randomness( 20, &zBuf[j] );
for( i = 0; i < 20; i++, j++ ){
- zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
+ zBuf[j] = zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
}
zBuf[j] = 0;
+
OSTRACE(( "TEMP FILENAME: %s\n", zBuf ));
return SQLITE_OK;
}
char *zRelativeCp = convertUtf8PathToCp( zRelative );
char zFullCp[CCHMAXPATH] = "\0";
char *zFullUTF;
- APIRET rc = DosQueryPathInfo( zRelativeCp, FIL_QUERYFULLNAME, zFullCp,
- CCHMAXPATH );
+ APIRET rc = DosQueryPathInfo( (PSZ)zRelativeCp, FIL_QUERYFULLNAME,
+ zFullCp, CCHMAXPATH );
free( zRelativeCp );
zFullUTF = convertCpPathToUtf8( zFullCp );
sqlite3_snprintf( nFull, zFull, zFullUTF );
char zTmpname[CCHMAXPATH];
int isExclusive = (flags & SQLITE_OPEN_EXCLUSIVE);
- int isDelete = (flags & SQLITE_OPEN_DELETEONCLOSE);
int isCreate = (flags & SQLITE_OPEN_CREATE);
int isReadWrite = (flags & SQLITE_OPEN_READWRITE);
#ifndef NDEBUG
+ int isDelete = (flags & SQLITE_OPEN_DELETEONCLOSE);
int isReadonly = (flags & SQLITE_OPEN_READONLY);
int eType = (flags & 0xFFFFFF00);
int isOpenJournal = (isCreate && (
);
memset( pFile, 0, sizeof(*pFile) );
- pFile->pMethod = &os2IoMethod;
+ pFile->h = (HFILE)-1;
/* If the second argument to this function is NULL, generate a
** temporary file name to use
/* Open in random access mode for possibly better speed. Allow full
** sharing because file locks will provide exclusive access when needed.
+ ** The handle should not be inherited by child processes and we don't
+ ** want popups from the critical error handler.
*/
- ulOpenMode |= OPEN_FLAGS_RANDOM;
- ulOpenMode |= OPEN_FLAGS_FAIL_ON_ERROR;
- ulOpenMode |= OPEN_FLAGS_NOINHERIT;
- ulOpenMode |= OPEN_SHARE_DENYNONE;
+ ulOpenMode |= OPEN_FLAGS_RANDOM | OPEN_SHARE_DENYNONE |
+ OPEN_FLAGS_NOINHERIT | OPEN_FLAGS_FAIL_ON_ERROR;
/* SQLITE_OPEN_EXCLUSIVE is used to make sure that a new file is
** created. SQLite doesn't use it to indicate "exclusive access"
ulOpenFlags |= OPEN_ACTION_FAIL_IF_NEW | OPEN_ACTION_OPEN_IF_EXISTS;
}
- /* For DELETEONCLOSE, save a pointer to the converted filename */
- if( isDelete ){
- char pathUtf8[CCHMAXPATH];
- os2FullPathname( pVfs, zUtf8Name, CCHMAXPATH, pathUtf8 );
- pFile->pathToDel = convertUtf8PathToCp( pathUtf8 );
- }
-
zNameCp = convertUtf8PathToCp( zUtf8Name );
rc = DosOpen( (PSZ)zNameCp,
&h,
if( rc != NO_ERROR ){
OSTRACE(( "OPEN Invalid handle rc=%d: zName=%s, ulAction=%#lx, ulFlags=%#lx, ulMode=%#lx\n",
rc, zUtf8Name, ulAction, ulOpenFlags, ulOpenMode ));
- if( pFile->pathToDel )
- free( pFile->pathToDel );
- pFile->pathToDel = NULL;
if( isReadWrite ){
return os2Open( pVfs, zName, id,
*pOutFlags = isReadWrite ? SQLITE_OPEN_READWRITE : SQLITE_OPEN_READONLY;
}
+ os2FullPathname( pVfs, zUtf8Name, sizeof( zTmpname ), zTmpname );
+ pFile->zFullPathCp = convertUtf8PathToCp( zTmpname );
+ pFile->pMethod = &os2IoMethod;
+ pFile->flags = flags;
pFile->h = h;
+
OpenCounter(+1);
OSTRACE(( "OPEN %d pOutFlags=%d\n", pFile->h, pOutFlags ));
return SQLITE_OK;
int flags, /* Type of test to make on this file */
int *pOut /* Write results here */
){
+ APIRET rc;
FILESTATUS3 fsts3ConfigInfo;
- APIRET rc = NO_ERROR;
- char *zFilenameCp = convertUtf8PathToCp( zFilename );
+ char *zFilenameCp;
- memset( &fsts3ConfigInfo, 0, sizeof(fsts3ConfigInfo) );
+ UNUSED_PARAMETER(pVfs);
+ SimulateIOError( return SQLITE_IOERR_ACCESS; );
+
+ zFilenameCp = convertUtf8PathToCp( zFilename );
rc = DosQueryPathInfo( (PSZ)zFilenameCp, FIL_STANDARD,
&fsts3ConfigInfo, sizeof(FILESTATUS3) );
free( zFilenameCp );
OSTRACE(( "ACCESS fsts3ConfigInfo.attrFile=%d flags=%d rc=%d\n",
fsts3ConfigInfo.attrFile, flags, rc ));
+
switch( flags ){
- case SQLITE_ACCESS_READ:
case SQLITE_ACCESS_EXISTS:
- rc = (rc == NO_ERROR);
- OSTRACE(( "ACCESS %s access of read and exists rc=%d\n", zFilename, rc));
+ /* For an SQLITE_ACCESS_EXISTS query, treat a zero-length file
+ ** as if it does not exist.
+ */
+ if( fsts3ConfigInfo.cbFile == 0 )
+ rc = ERROR_FILE_NOT_FOUND;
+ break;
+ case SQLITE_ACCESS_READ:
break;
case SQLITE_ACCESS_READWRITE:
- rc = (rc == NO_ERROR) && ( (fsts3ConfigInfo.attrFile & FILE_READONLY) == 0 );
- OSTRACE(( "ACCESS %s access of read/write rc=%d\n", zFilename, rc ));
+ if( fsts3ConfigInfo.attrFile & FILE_READONLY )
+ rc = ERROR_ACCESS_DENIED;
break;
default:
+ rc = ERROR_FILE_NOT_FOUND;
assert( !"Invalid flags argument" );
}
- *pOut = rc;
+
+ *pOut = (rc == NO_ERROR);
+ OSTRACE(( "ACCESS %s flags %d: rc=%d\n", zFilename, flags, *pOut ));
+
return SQLITE_OK;
}
** within the shared library, and closing the shared library.
*/
static void *os2DlOpen(sqlite3_vfs *pVfs, const char *zFilename){
- UCHAR loadErr[256];
HMODULE hmod;
APIRET rc;
char *zFilenameCp = convertUtf8PathToCp(zFilename);
- rc = DosLoadModule((PSZ)loadErr, sizeof(loadErr), zFilenameCp, &hmod);
+ rc = DosLoadModule(NULL, 0, (PSZ)zFilenameCp, &hmod);
free(zFilenameCp);
return rc != NO_ERROR ? 0 : (void*)hmod;
}
static void (*os2DlSym(sqlite3_vfs *pVfs, void *pHandle, const char *zSymbol))(void){
PFN pfn;
APIRET rc;
- rc = DosQueryProcAddr((HMODULE)pHandle, 0L, zSymbol, &pfn);
+ rc = DosQueryProcAddr((HMODULE)pHandle, 0L, (PSZ)zSymbol, &pfn);
if( rc != NO_ERROR ){
/* if the symbol itself was not found, search again for the same
* symbol with an extra underscore, that might be needed depending
* on the calling convention */
char _zSymbol[256] = "_";
- strncat(_zSymbol, zSymbol, 255);
- rc = DosQueryProcAddr((HMODULE)pHandle, 0L, _zSymbol, &pfn);
+ strncat(_zSymbol, zSymbol, 254);
+ rc = DosQueryProcAddr((HMODULE)pHandle, 0L, (PSZ)_zSymbol, &pfn);
}
return rc != NO_ERROR ? 0 : (void(*)(void))pfn;
}
n = nBuf;
memset(zBuf, 0, nBuf);
#else
- int sizeofULong = sizeof(ULONG);
- if( (int)sizeof(DATETIME) <= nBuf - n ){
- DATETIME x;
- DosGetDateTime(&x);
- memcpy(&zBuf[n], &x, sizeof(x));
- n += sizeof(x);
- }
-
- if( sizeofULong <= nBuf - n ){
- PPIB ppib;
- DosGetInfoBlocks(NULL, &ppib);
- memcpy(&zBuf[n], &ppib->pib_ulpid, sizeofULong);
- n += sizeofULong;
+ int i;
+ PPIB ppib;
+ PTIB ptib;
+ DATETIME dt;
+ static unsigned c = 0;
+ /* Ordered by variation probability */
+ static ULONG svIdx[6] = { QSV_MS_COUNT, QSV_TIME_LOW,
+ QSV_MAXPRMEM, QSV_MAXSHMEM,
+ QSV_TOTAVAILMEM, QSV_TOTRESMEM };
+
+ /* 8 bytes; timezone and weekday don't increase the randomness much */
+ if( (int)sizeof(dt)-3 <= nBuf - n ){
+ c += 0x0100;
+ DosGetDateTime(&dt);
+ dt.year = (USHORT)((dt.year - 1900) | c);
+ memcpy(&zBuf[n], &dt, sizeof(dt)-3);
+ n += sizeof(dt)-3;
}
- if( sizeofULong <= nBuf - n ){
- PTIB ptib;
- DosGetInfoBlocks(&ptib, NULL);
- memcpy(&zBuf[n], &ptib->tib_ptib2->tib2_ultid, sizeofULong);
- n += sizeofULong;
+ /* 4 bytes; PIDs and TIDs are 16 bit internally, so combine them */
+ if( (int)sizeof(ULONG) <= nBuf - n ){
+ DosGetInfoBlocks(&ptib, &ppib);
+ *(PULONG)&zBuf[n] = MAKELONG(ppib->pib_ulpid,
+ ptib->tib_ptib2->tib2_ultid);
+ n += sizeof(ULONG);
}
- /* if we still haven't filled the buffer yet the following will */
- /* grab everything once instead of making several calls for a single item */
- if( sizeofULong <= nBuf - n ){
- ULONG ulSysInfo[QSV_MAX];
- DosQuerySysInfo(1L, QSV_MAX, ulSysInfo, sizeofULong * QSV_MAX);
-
- memcpy(&zBuf[n], &ulSysInfo[QSV_MS_COUNT - 1], sizeofULong);
- n += sizeofULong;
-
- if( sizeofULong <= nBuf - n ){
- memcpy(&zBuf[n], &ulSysInfo[QSV_TIMER_INTERVAL - 1], sizeofULong);
- n += sizeofULong;
- }
- if( sizeofULong <= nBuf - n ){
- memcpy(&zBuf[n], &ulSysInfo[QSV_TIME_LOW - 1], sizeofULong);
- n += sizeofULong;
- }
- if( sizeofULong <= nBuf - n ){
- memcpy(&zBuf[n], &ulSysInfo[QSV_TIME_HIGH - 1], sizeofULong);
- n += sizeofULong;
- }
- if( sizeofULong <= nBuf - n ){
- memcpy(&zBuf[n], &ulSysInfo[QSV_TOTAVAILMEM - 1], sizeofULong);
- n += sizeofULong;
- }
- }
+ /* Up to 6 * 4 bytes; variables depend on the system state */
+ for( i = 0; i < 6 && (int)sizeof(ULONG) <= nBuf - n; i++ ){
+ DosQuerySysInfo(svIdx[i], svIdx[i],
+ (PULONG)&zBuf[n], sizeof(ULONG));
+ n += sizeof(ULONG);
+ }
#endif
return n;
#endif
/*
-** Find the current time (in Universal Coordinated Time). Write the
-** current time and date as a Julian Day number into *prNow and
-** return 0. Return 1 if the time and date cannot be found.
+** Find the current time (in Universal Coordinated Time). Write into *piNow
+** the current time and date as a Julian Day number times 86_400_000. In
+** other words, write into *piNow the number of milliseconds since the Julian
+** epoch of noon in Greenwich on November 24, 4714 B.C according to the
+** proleptic Gregorian calendar.
+**
+** On success, return 0. Return 1 if the time and date cannot be found.
*/
-int os2CurrentTime( sqlite3_vfs *pVfs, double *prNow ){
- double now;
- SHORT minute; /* needs to be able to cope with negative timezone offset */
- USHORT hundredths, second, hour,
- day, month, year;
+static int os2CurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *piNow){
+#ifdef SQLITE_TEST
+ static const sqlite3_int64 unixEpoch = 24405875*(sqlite3_int64)8640000;
+#endif
+ int year, month, datepart, timepart;
+
DATETIME dt;
DosGetDateTime( &dt );
- hundredths = (USHORT)dt.hundredths;
- second = (USHORT)dt.seconds;
- minute = (SHORT)dt.minutes + dt.timezone;
- hour = (USHORT)dt.hours;
- day = (USHORT)dt.day;
- month = (USHORT)dt.month;
- year = (USHORT)dt.year;
+
+ year = dt.year;
+ month = dt.month;
/* Calculations from http://www.astro.keele.ac.uk/~rno/Astronomy/hjd.html
- http://www.astro.keele.ac.uk/~rno/Astronomy/hjd-0.1.c */
- /* Calculate the Julian days */
- now = day - 32076 +
+ ** http://www.astro.keele.ac.uk/~rno/Astronomy/hjd-0.1.c
+ ** Calculate the Julian days
+ */
+ datepart = (int)dt.day - 32076 +
1461*(year + 4800 + (month - 14)/12)/4 +
367*(month - 2 - (month - 14)/12*12)/12 -
3*((year + 4900 + (month - 14)/12)/100)/4;
- /* Add the fractional hours, mins and seconds */
- now += (hour + 12.0)/24.0;
- now += minute/1440.0;
- now += second/86400.0;
- now += hundredths/8640000.0;
- *prNow = now;
+ /* Time in milliseconds, hours to noon added */
+ timepart = 12*3600*1000 + dt.hundredths*10 + dt.seconds*1000 +
+ ((int)dt.minutes + dt.timezone)*60*1000 + dt.hours*3600*1000;
+
+ *piNow = (sqlite3_int64)datepart*86400*1000 + timepart;
+
#ifdef SQLITE_TEST
if( sqlite3_current_time ){
- *prNow = sqlite3_current_time/86400.0 + 2440587.5;
+ *piNow = 1000*(sqlite3_int64)sqlite3_current_time + unixEpoch;
}
#endif
+
+ UNUSED_PARAMETER(pVfs);
return 0;
}
/*
-** Find the current time (in Universal Coordinated Time). Write into *piNow
-** the current time and date as a Julian Day number times 86_400_000. In
-** other words, write into *piNow the number of milliseconds since the Julian
-** epoch of noon in Greenwich on November 24, 4714 B.C according to the
-** proleptic Gregorian calendar.
-**
-** On success, return 0. Return 1 if the time and date cannot be found.
+** Find the current time (in Universal Coordinated Time). Write the
+** current time and date as a Julian Day number into *prNow and
+** return 0. Return 1 if the time and date cannot be found.
*/
-static int os2CurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *piNow){
- double now;
- os2CurrentTime(pVfs, &now);
- *piNow = now * 86400000;
- return 0;
+int os2CurrentTime( sqlite3_vfs *pVfs, double *prNow ){
+ int rc;
+ sqlite3_int64 i;
+ rc = os2CurrentTimeInt64(pVfs, &i);
+ if( !rc ){
+ *prNow = i/86400000.0;
+ }
+ return rc;
}
+/*
+** The idea is that this function works like a combination of
+** GetLastError() and FormatMessage() on windows (or errno and
+** strerror_r() on unix). After an error is returned by an OS
+** function, SQLite calls this function with zBuf pointing to
+** a buffer of nBuf bytes. The OS layer should populate the
+** buffer with a nul-terminated UTF-8 encoded error message
+** describing the last IO error to have occurred within the calling
+** thread.
+**
+** If the error message is too large for the supplied buffer,
+** it should be truncated. The return value of xGetLastError
+** is zero if the error message fits in the buffer, or non-zero
+** otherwise (if the message was truncated). If non-zero is returned,
+** then it is not necessary to include the nul-terminator character
+** in the output buffer.
+**
+** Not supplying an error message will have no adverse effect
+** on SQLite. It is fine to have an implementation that never
+** returns an error message:
+**
+** int xGetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
+** assert(zBuf[0]=='\0');
+** return 0;
+** }
+**
+** However if an error message is supplied, it will be incorporated
+** by sqlite into the error message available to the user using
+** sqlite3_errmsg(), possibly making IO errors easier to debug.
+*/
static int os2GetLastError(sqlite3_vfs *pVfs, int nBuf, char *zBuf){
+ assert(zBuf[0]=='\0');
return 0;
}
os2Sleep, /* xSleep */
os2CurrentTime, /* xCurrentTime */
os2GetLastError, /* xGetLastError */
- os2CurrentTimeInt64 /* xCurrentTimeInt64 */
+ os2CurrentTimeInt64, /* xCurrentTimeInt64 */
0, /* xSetSystemCall */
0, /* xGetSystemCall */
- 0, /* xNextSystemCall */
+ 0 /* xNextSystemCall */
};
sqlite3_vfs_register(&os2Vfs, 1);
initUconvObjects();
+/* sqlite3OSTrace = 1; */
return SQLITE_OK;
}
int sqlite3_os_end(void){
projects / thirdparty / sqlite.git / commitdiff
