int nRead; /* Database pages read */
#endif
void (*xReiniter)(DbPage*); /* Call this routine when reloading pages */
+ int (*xGet)(Pager*,Pgno,DbPage**,int); /* Routine to fetch a patch */
#ifdef SQLITE_HAS_CODEC
void *(*xCodec)(void*,void*,Pgno,int); /* Routine for en/decoding data */
void (*xCodecSizeChng)(void*,int,int); /* Notify of page size changes */
}
#endif
+/* Forward references to the various page getters */
+static int getPageNormal(Pager*,Pgno,DbPage**,int);
+static int getPageMMap(Pager*,Pgno,DbPage**,int);
+static int getPageError(Pager*,Pgno,DbPage**,int);
+
+/*
+** Set the Pager.xGet method for the appropriate routine used to fetch
+** content from the pager.
+*/
+static void setGetterMethod(Pager *pPager){
+ if( pPager->errCode ){
+ pPager->xGet = getPageError;
+ }else if( USEFETCH(pPager)
+#ifdef SQLITE_HAS_CODEC
+ && pPager->xCodec==0
+#endif
+ ){
+ pPager->xGet = getPageMMap;
+ }else{
+ pPager->xGet = getPageNormal;
+ }
+}
+
/*
** Return true if it is necessary to write page *pPg into the sub-journal.
** A page needs to be written into the sub-journal if there exists one
}
if( USEFETCH(pPager) ) sqlite3OsUnfetch(pPager->fd, 0, 0);
pPager->errCode = SQLITE_OK;
+ setGetterMethod(pPager);
}
pPager->journalOff = 0;
if( rc2==SQLITE_FULL || rc2==SQLITE_IOERR ){
pPager->errCode = rc;
pPager->eState = PAGER_ERROR;
+ setGetterMethod(pPager);
}
return rc;
}
sqlite3_int64 sz;
sz = pPager->szMmap;
pPager->bUseFetch = (sz>0);
+ setGetterMethod(pPager);
sqlite3OsFileControlHint(pPager->fd, SQLITE_FCNTL_MMAP_SIZE, &sz);
}
#endif
/* pPager->xBusyHandler = 0; */
/* pPager->pBusyHandlerArg = 0; */
pPager->xReiniter = xReinit;
+ setGetterMethod(pPager);
/* memset(pPager->aHash, 0, sizeof(pPager->aHash)); */
/* pPager->szMmap = SQLITE_DEFAULT_MMAP_SIZE // will be set by btree.c */
** Since Lookup() never goes to disk, it never has to deal with locks
** or journal files.
*/
-int sqlite3PagerGet(
+static int getPageNormal(
Pager *pPager, /* The pager open on the database file */
Pgno pgno, /* Page number to fetch */
DbPage **ppPage, /* Write a pointer to the page here */
PgHdr *pPg = 0;
u32 iFrame = 0; /* Frame to read from WAL file */
const int noContent = (flags & PAGER_GET_NOCONTENT);
+ sqlite3_pcache_page *pBase;
- /* It is acceptable to use a read-only (mmap) page for any page except
- ** page 1 if there is no write-transaction open or the ACQUIRE_READONLY
- ** flag was specified by the caller. And so long as the db is not a
- ** temporary or in-memory database. */
- const int bMmapOk = (pgno>1 && USEFETCH(pPager)
- && (pPager->eState==PAGER_READER || (flags & PAGER_GET_READONLY))
-#ifdef SQLITE_HAS_CODEC
- && pPager->xCodec==0
-#endif
- );
-
- /* Optimization note: Adding the "pgno<=1" term before "pgno==0" here
- ** allows the compiler optimizer to reuse the results of the "pgno>1"
- ** test in the previous statement, and avoid testing pgno==0 in the
- ** common case where pgno is large. */
- if( pgno<=1 && pgno==0 ){
+ if( pgno==0 ){
return SQLITE_CORRUPT_BKPT;
}
+ assert( pPager->errCode==SQLITE_OK );
assert( pPager->eState>=PAGER_READER );
assert( assert_pager_state(pPager) );
- assert( noContent==0 || bMmapOk==0 );
-
assert( pPager->hasHeldSharedLock==1 );
- /* If the pager is in the error state, return an error immediately.
- ** Otherwise, request the page from the PCache layer. */
- if( pPager->errCode!=SQLITE_OK ){
- rc = pPager->errCode;
- }else{
- if( bMmapOk && pagerUseWal(pPager) ){
- rc = sqlite3WalFindFrame(pPager->pWal, pgno, &iFrame);
- if( rc!=SQLITE_OK ) goto pager_acquire_err;
- }
-
- if( bMmapOk && iFrame==0 ){
- void *pData = 0;
-
- rc = sqlite3OsFetch(pPager->fd,
- (i64)(pgno-1) * pPager->pageSize, pPager->pageSize, &pData
- );
-
- if( rc==SQLITE_OK && pData ){
- if( pPager->eState>PAGER_READER || pPager->tempFile ){
- pPg = sqlite3PagerLookup(pPager, pgno);
- }
- if( pPg==0 ){
- rc = pagerAcquireMapPage(pPager, pgno, pData, &pPg);
- }else{
- sqlite3OsUnfetch(pPager->fd, (i64)(pgno-1)*pPager->pageSize, pData);
- }
- if( pPg ){
- assert( rc==SQLITE_OK );
- *ppPage = pPg;
- return SQLITE_OK;
- }
- }
- if( rc!=SQLITE_OK ){
- goto pager_acquire_err;
- }
- }
- {
- sqlite3_pcache_page *pBase;
- pBase = sqlite3PcacheFetch(pPager->pPCache, pgno, 3);
- if( pBase==0 ){
- rc = sqlite3PcacheFetchStress(pPager->pPCache, pgno, &pBase);
- if( rc!=SQLITE_OK ) goto pager_acquire_err;
- if( pBase==0 ){
- pPg = *ppPage = 0;
- rc = SQLITE_NOMEM_BKPT;
- goto pager_acquire_err;
- }
- }
- pPg = *ppPage = sqlite3PcacheFetchFinish(pPager->pPCache, pgno, pBase);
- assert( pPg!=0 );
+ pBase = sqlite3PcacheFetch(pPager->pPCache, pgno, 3);
+ if( pBase==0 ){
+ rc = sqlite3PcacheFetchStress(pPager->pPCache, pgno, &pBase);
+ if( rc!=SQLITE_OK ) goto pager_acquire_err;
+ if( pBase==0 ){
+ pPg = *ppPage = 0;
+ rc = SQLITE_NOMEM_BKPT;
+ goto pager_acquire_err;
}
}
-
- if( rc!=SQLITE_OK ){
- /* Either the call to sqlite3PcacheFetch() returned an error or the
- ** pager was already in the error-state when this function was called.
- ** Set pPg to 0 and jump to the exception handler. */
- pPg = 0;
- goto pager_acquire_err;
- }
+ pPg = *ppPage = sqlite3PcacheFetchFinish(pPager->pPCache, pgno, pBase);
assert( pPg==(*ppPage) );
assert( pPg->pgno==pgno );
assert( pPg->pPager==pPager || pPg->pPager==0 );
memset(pPg->pData, 0, pPager->pageSize);
IOTRACE(("ZERO %p %d\n", pPager, pgno));
}else{
- if( pagerUseWal(pPager) && bMmapOk==0 ){
+ if( pagerUseWal(pPager) /*&& bMmapOk==0*/ ){
rc = sqlite3WalFindFrame(pPager->pWal, pgno, &iFrame);
if( rc!=SQLITE_OK ) goto pager_acquire_err;
}
}
pager_set_pagehash(pPg);
}
-
return SQLITE_OK;
pager_acquire_err:
sqlite3PcacheDrop(pPg);
}
pagerUnlockIfUnused(pPager);
-
*ppPage = 0;
return rc;
}
+/* The page getter for when memory-mapped I/O is enabled */
+static int getPageMMap(
+ Pager *pPager, /* The pager open on the database file */
+ Pgno pgno, /* Page number to fetch */
+ DbPage **ppPage, /* Write a pointer to the page here */
+ int flags /* PAGER_GET_XXX flags */
+){
+ int rc = SQLITE_OK;
+ PgHdr *pPg = 0;
+ u32 iFrame = 0; /* Frame to read from WAL file */
+
+ assert( USEFETCH(pPager) );
+#ifdef SQLITE_HAS_CODEC
+ assert( pPager->xCodec==0 );
+#endif
+
+ /* It is acceptable to use a read-only (mmap) page for any page except
+ ** page 1 if there is no write-transaction open or the ACQUIRE_READONLY
+ ** flag was specified by the caller. And so long as the db is not a
+ ** temporary or in-memory database. */
+ const int bMmapOk = (pgno>1
+ && (pPager->eState==PAGER_READER || (flags & PAGER_GET_READONLY))
+ );
+
+ /* Optimization note: Adding the "pgno<=1" term before "pgno==0" here
+ ** allows the compiler optimizer to reuse the results of the "pgno>1"
+ ** test in the previous statement, and avoid testing pgno==0 in the
+ ** common case where pgno is large. */
+ if( pgno<=1 && pgno==0 ){
+ return SQLITE_CORRUPT_BKPT;
+ }
+ assert( pPager->eState>=PAGER_READER );
+ assert( assert_pager_state(pPager) );
+ assert( pPager->hasHeldSharedLock==1 );
+ assert( pPager->errCode==SQLITE_OK );
+
+ if( bMmapOk && pagerUseWal(pPager) ){
+ rc = sqlite3WalFindFrame(pPager->pWal, pgno, &iFrame);
+ if( rc!=SQLITE_OK ){
+ *ppPage = 0;
+ return rc;
+ }
+ }
+ if( bMmapOk && iFrame==0 ){
+ void *pData = 0;
+ rc = sqlite3OsFetch(pPager->fd,
+ (i64)(pgno-1) * pPager->pageSize, pPager->pageSize, &pData
+ );
+ if( rc==SQLITE_OK && pData ){
+ if( pPager->eState>PAGER_READER || pPager->tempFile ){
+ pPg = sqlite3PagerLookup(pPager, pgno);
+ }
+ if( pPg==0 ){
+ rc = pagerAcquireMapPage(pPager, pgno, pData, &pPg);
+ }else{
+ sqlite3OsUnfetch(pPager->fd, (i64)(pgno-1)*pPager->pageSize, pData);
+ }
+ if( pPg ){
+ assert( rc==SQLITE_OK );
+ *ppPage = pPg;
+ return SQLITE_OK;
+ }
+ }
+ if( rc!=SQLITE_OK ){
+ *ppPage = 0;
+ return rc;
+ }
+ }
+ return getPageNormal(pPager, pgno, ppPage, flags);
+}
+
+/* The page getter method for when the pager is an error state */
+static int getPageError(
+ Pager *pPager, /* The pager open on the database file */
+ Pgno pgno, /* Page number to fetch */
+ DbPage **ppPage, /* Write a pointer to the page here */
+ int flags /* PAGER_GET_XXX flags */
+){
+ assert( pPager->errCode!=SQLITE_OK );
+ *ppPage = 0;
+ return pPager->errCode;
+}
+
+
+/* Dispatch all page fetch requests to the appropriate getter method.
+*/
+int sqlite3PagerGet(
+ Pager *pPager, /* The pager open on the database file */
+ Pgno pgno, /* Page number to fetch */
+ DbPage **ppPage, /* Write a pointer to the page here */
+ int flags /* PAGER_GET_XXX flags */
+){
+ return pPager->xGet(pPager, pgno, ppPage, flags);
+}
+
/*
** Acquire a page if it is already in the in-memory cache. Do
** not read the page from disk. Return a pointer to the page,
*/
pPager->errCode = SQLITE_ABORT;
pPager->eState = PAGER_ERROR;
+ setGetterMethod(pPager);
return rc;
}
}else{
){
pPager->errCode = SQLITE_ABORT;
pPager->eState = PAGER_ERROR;
+ setGettterMethod(pPager);
}
#endif
}
pPager->xCodecSizeChng = xCodecSizeChng;
pPager->xCodecFree = xCodecFree;
pPager->pCodec = pCodec;
+ setGetterMethod(pPager);
pagerReportSize(pPager);
}
void *sqlite3PagerGetCodec(Pager *pPager){
projects / thirdparty / sqlite.git / commitdiff
