diff options
Diffstat (limited to 'src/vdbeblob.c')
-rw-r--r-- | src/vdbeblob.c | 174 |
1 files changed, 117 insertions, 57 deletions
diff --git a/src/vdbeblob.c b/src/vdbeblob.c index b2b9f0ed0..f7ee670f2 100644 --- a/src/vdbeblob.c +++ b/src/vdbeblob.c @@ -26,11 +26,61 @@ struct Incrblob { int flags; /* Copy of "flags" passed to sqlite3_blob_open() */ int nByte; /* Size of open blob, in bytes */ int iOffset; /* Byte offset of blob in cursor data */ + int iCol; /* Table column this handle is open on */ BtCursor *pCsr; /* Cursor pointing at blob row */ sqlite3_stmt *pStmt; /* Statement holding cursor open */ sqlite3 *db; /* The associated database */ }; + +static int blobSeekToRow(Incrblob *p, sqlite3_int64 iRow, char **pzErr){ + int rc; /* Error code */ + char *zErr = 0; /* Error message */ + Vdbe *v = (Vdbe *)p->pStmt; + + v->aVar[0].u.i = iRow; + rc = sqlite3_step(p->pStmt); + + if( rc==SQLITE_ROW ){ + Vdbe *v = (Vdbe *)p->pStmt; + u32 type = v->apCsr[0]->aType[p->iCol]; + if( type<12 ){ + zErr = sqlite3MPrintf(p->db, "cannot open value of type %s", + type==0?"null": type==7?"real": "integer" + ); + rc = SQLITE_ERROR; + sqlite3_finalize(p->pStmt); + p->pStmt = 0; + }else{ + p->iOffset = v->apCsr[0]->aOffset[p->iCol]; + p->nByte = sqlite3VdbeSerialTypeLen(type); + p->pCsr = v->apCsr[0]->pCursor; + sqlite3BtreeEnterCursor(p->pCsr); + sqlite3BtreeCacheOverflow(p->pCsr); + sqlite3BtreeLeaveCursor(p->pCsr); + } + } + + if( rc==SQLITE_ROW ){ + rc = SQLITE_OK; + }else if( p->pStmt ){ + rc = sqlite3_finalize(p->pStmt); + p->pStmt = 0; + if( rc==SQLITE_OK ){ + zErr = sqlite3MPrintf(p->db, "no such rowid: %lld", iRow); + rc = SQLITE_ERROR; + }else{ + zErr = sqlite3MPrintf(p->db, "%s", sqlite3_errmsg(p->db)); + } + } + + assert( rc!=SQLITE_OK || zErr==0 ); + assert( rc!=SQLITE_ROW && rc!=SQLITE_DONE ); + + *pzErr = zErr; + return rc; +} + /* ** Open a blob handle. */ @@ -71,11 +121,12 @@ int sqlite3_blob_open( {OP_OpenWrite, 0, 0, 0}, /* 4: Open cursor 0 for read/write */ {OP_Variable, 1, 1, 1}, /* 5: Push the rowid to the stack */ - {OP_NotExists, 0, 9, 1}, /* 6: Seek the cursor */ + {OP_NotExists, 0, 10, 1}, /* 6: Seek the cursor */ {OP_Column, 0, 0, 1}, /* 7 */ {OP_ResultRow, 1, 0, 0}, /* 8 */ - {OP_Close, 0, 0, 0}, /* 9 */ - {OP_Halt, 0, 0, 0}, /* 10 */ + {OP_Goto, 0, 5, 0}, /* 9 */ + {OP_Close, 0, 0, 0}, /* 10 */ + {OP_Halt, 0, 0, 0}, /* 11 */ }; Vdbe *v = 0; @@ -83,14 +134,20 @@ int sqlite3_blob_open( char *zErr = 0; Table *pTab; Parse *pParse; + Incrblob *pBlob; + flags = !!flags; /* flags = (flags ? 1 : 0); */ *ppBlob = 0; + sqlite3_mutex_enter(db->mutex); + + pBlob = (Incrblob *)sqlite3DbMallocZero(db, sizeof(Incrblob)); pParse = sqlite3StackAllocRaw(db, sizeof(*pParse)); - if( pParse==0 ){ - rc = SQLITE_NOMEM; + if( pParse==0 || pBlob==0 ){ + assert( db->mallocFailed ); goto blob_open_out; } + do { memset(pParse, 0, sizeof(Parse)); pParse->db = db; @@ -177,7 +234,6 @@ int sqlite3_blob_open( if( v ){ int iDb = sqlite3SchemaToIndex(db, pTab->pSchema); sqlite3VdbeAddOpList(v, sizeof(openBlob)/sizeof(VdbeOpList), openBlob); - flags = !!flags; /* flags = (flags ? 1 : 0); */ /* Configure the OP_Transaction */ sqlite3VdbeChangeP1(v, 0, iDb); @@ -220,65 +276,30 @@ int sqlite3_blob_open( } } + pBlob->flags = flags; + pBlob->pStmt = (sqlite3_stmt *)v; + pBlob->iCol = iCol; + pBlob->db = db; sqlite3BtreeLeaveAll(db); + v = 0; if( db->mallocFailed ){ goto blob_open_out; } - sqlite3_bind_int64((sqlite3_stmt *)v, 1, iRow); - rc = sqlite3_step((sqlite3_stmt *)v); - if( rc!=SQLITE_ROW ){ - nAttempt++; - rc = sqlite3_finalize((sqlite3_stmt *)v); - sqlite3DbFree(db, zErr); - zErr = sqlite3MPrintf(db, sqlite3_errmsg(db)); - v = 0; - } - } while( nAttempt<5 && rc==SQLITE_SCHEMA ); - - if( rc==SQLITE_ROW ){ - /* The row-record has been opened successfully. Check that the - ** column in question contains text or a blob. If it contains - ** text, it is up to the caller to get the encoding right. - */ - Incrblob *pBlob; - u32 type = v->apCsr[0]->aType[iCol]; + sqlite3_bind_int64(pBlob->pStmt, 1, iRow); + rc = blobSeekToRow(pBlob, iRow, &zErr); + } while( (++nAttempt)<5 && rc==SQLITE_SCHEMA ); - if( type<12 ){ - sqlite3DbFree(db, zErr); - zErr = sqlite3MPrintf(db, "cannot open value of type %s", - type==0?"null": type==7?"real": "integer" - ); - rc = SQLITE_ERROR; - goto blob_open_out; - } - pBlob = (Incrblob *)sqlite3DbMallocZero(db, sizeof(Incrblob)); - if( db->mallocFailed ){ - sqlite3DbFree(db, pBlob); - goto blob_open_out; - } - pBlob->flags = flags; - pBlob->pCsr = v->apCsr[0]->pCursor; - sqlite3BtreeEnterCursor(pBlob->pCsr); - sqlite3BtreeCacheOverflow(pBlob->pCsr); - sqlite3BtreeLeaveCursor(pBlob->pCsr); - pBlob->pStmt = (sqlite3_stmt *)v; - pBlob->iOffset = v->apCsr[0]->aOffset[iCol]; - pBlob->nByte = sqlite3VdbeSerialTypeLen(type); - pBlob->db = db; +blob_open_out: + if( rc==SQLITE_OK && db->mallocFailed==0 ){ *ppBlob = (sqlite3_blob *)pBlob; - rc = SQLITE_OK; - }else if( rc==SQLITE_OK ){ - sqlite3DbFree(db, zErr); - zErr = sqlite3MPrintf(db, "no such rowid: %lld", iRow); - rc = SQLITE_ERROR; + }else{ + if( v ) sqlite3VdbeFinalize(v); + if( pBlob && pBlob->pStmt ) sqlite3VdbeFinalize((Vdbe *)pBlob->pStmt); + sqlite3DbFree(db, pBlob); } -blob_open_out: - if( v && (rc!=SQLITE_OK || db->mallocFailed) ){ - sqlite3VdbeFinalize(v); - } - sqlite3Error(db, rc, zErr); + sqlite3Error(db, rc, (zErr ? "%s" : 0), zErr); sqlite3DbFree(db, zErr); sqlite3StackFree(db, pParse); rc = sqlite3ApiExit(db, rc); @@ -331,7 +352,7 @@ static int blobReadWrite( /* Request is out of range. Return a transient error. */ rc = SQLITE_ERROR; sqlite3Error(db, SQLITE_ERROR, 0); - } else if( v==0 ){ + }else if( v==0 ){ /* If there is no statement handle, then the blob-handle has ** already been invalidated. Return SQLITE_ABORT in this case. */ @@ -382,4 +403,43 @@ int sqlite3_blob_bytes(sqlite3_blob *pBlob){ return p ? p->nByte : 0; } +/* +** Move an existing blob handle to point to a different row of the same +** database table. +** +** If an error occurs, or if the specified row does not exist or does not +** contain a blob or text value, then an error code is returned and the +** database handle error code and message set. If this happens, then all +** subsequent calls to sqlite3_blob_xxx() functions (except blob_close()) +** immediately return SQLITE_ABORT. +*/ +int sqlite3_blob_reopen(sqlite3_blob *pBlob, sqlite3_int64 iRow){ + int rc; + Incrblob *p = (Incrblob *)pBlob; + sqlite3 *db; + + if( p==0 ) return SQLITE_MISUSE_BKPT; + db = p->db; + sqlite3_mutex_enter(db->mutex); + + if( p->pStmt==0 ){ + /* If there is no statement handle, then the blob-handle has + ** already been invalidated. Return SQLITE_ABORT in this case. + */ + rc = SQLITE_ABORT; + }else{ + char *zErr; + rc = blobSeekToRow(p, iRow, &zErr); + if( rc!=SQLITE_OK ){ + sqlite3Error(db, rc, (zErr ? "%s" : 0), zErr); + sqlite3DbFree(db, zErr); + } + assert( rc!=SQLITE_SCHEMA ); + } + + rc = sqlite3ApiExit(db, rc); + sqlite3_mutex_leave(db->mutex); + return rc; +} + #endif /* #ifndef SQLITE_OMIT_INCRBLOB */ |