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Diffstat (limited to 'lib/libsqlite3/src/vdbeblob.c')
-rw-r--r-- | lib/libsqlite3/src/vdbeblob.c | 476 |
1 files changed, 0 insertions, 476 deletions
diff --git a/lib/libsqlite3/src/vdbeblob.c b/lib/libsqlite3/src/vdbeblob.c deleted file mode 100644 index 30a329189e6..00000000000 --- a/lib/libsqlite3/src/vdbeblob.c +++ /dev/null @@ -1,476 +0,0 @@ -/* -** 2007 May 1 -** -** 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 code used to implement incremental BLOB I/O. -*/ - -#include "sqliteInt.h" -#include "vdbeInt.h" - -#ifndef SQLITE_OMIT_INCRBLOB - -/* -** Valid sqlite3_blob* handles point to Incrblob structures. -*/ -typedef struct Incrblob Incrblob; -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 */ -}; - - -/* -** This function is used by both blob_open() and blob_reopen(). It seeks -** the b-tree cursor associated with blob handle p to point to row iRow. -** If successful, SQLITE_OK is returned and subsequent calls to -** sqlite3_blob_read() or sqlite3_blob_write() access the specified row. -** -** If an error occurs, or if the specified row does not exist or does not -** contain a value of type TEXT or BLOB in the column nominated when the -** blob handle was opened, then an error code is returned and *pzErr may -** be set to point to a buffer containing an error message. It is the -** responsibility of the caller to free the error message buffer using -** sqlite3DbFree(). -** -** If an error does occur, then the b-tree cursor is closed. All subsequent -** calls to sqlite3_blob_read(), blob_write() or blob_reopen() will -** immediately return SQLITE_ABORT. -*/ -static int blobSeekToRow(Incrblob *p, sqlite3_int64 iRow, char **pzErr){ - int rc; /* Error code */ - char *zErr = 0; /* Error message */ - Vdbe *v = (Vdbe *)p->pStmt; - - /* Set the value of the SQL statements only variable to integer iRow. - ** This is done directly instead of using sqlite3_bind_int64() to avoid - ** triggering asserts related to mutexes. - */ - assert( v->aVar[0].flags&MEM_Int ); - v->aVar[0].u.i = iRow; - - rc = sqlite3_step(p->pStmt); - if( rc==SQLITE_ROW ){ - VdbeCursor *pC = v->apCsr[0]; - u32 type = pC->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 = pC->aType[p->iCol + pC->nField]; - p->nByte = sqlite3VdbeSerialTypeLen(type); - p->pCsr = pC->pCursor; - sqlite3BtreeIncrblobCursor(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. -*/ -int sqlite3_blob_open( - sqlite3* db, /* The database connection */ - const char *zDb, /* The attached database containing the blob */ - const char *zTable, /* The table containing the blob */ - const char *zColumn, /* The column containing the blob */ - sqlite_int64 iRow, /* The row containing the glob */ - int flags, /* True -> read/write access, false -> read-only */ - sqlite3_blob **ppBlob /* Handle for accessing the blob returned here */ -){ - int nAttempt = 0; - int iCol; /* Index of zColumn in row-record */ - - /* This VDBE program seeks a btree cursor to the identified - ** db/table/row entry. The reason for using a vdbe program instead - ** of writing code to use the b-tree layer directly is that the - ** vdbe program will take advantage of the various transaction, - ** locking and error handling infrastructure built into the vdbe. - ** - ** After seeking the cursor, the vdbe executes an OP_ResultRow. - ** Code external to the Vdbe then "borrows" the b-tree cursor and - ** uses it to implement the blob_read(), blob_write() and - ** blob_bytes() functions. - ** - ** The sqlite3_blob_close() function finalizes the vdbe program, - ** which closes the b-tree cursor and (possibly) commits the - ** transaction. - */ - static const int iLn = VDBE_OFFSET_LINENO(4); - static const VdbeOpList openBlob[] = { - /* {OP_Transaction, 0, 0, 0}, // 0: Inserted separately */ - {OP_TableLock, 0, 0, 0}, /* 1: Acquire a read or write lock */ - /* One of the following two instructions is replaced by an OP_Noop. */ - {OP_OpenRead, 0, 0, 0}, /* 2: Open cursor 0 for reading */ - {OP_OpenWrite, 0, 0, 0}, /* 3: Open cursor 0 for read/write */ - {OP_Variable, 1, 1, 1}, /* 4: Push the rowid to the stack */ - {OP_NotExists, 0, 10, 1}, /* 5: Seek the cursor */ - {OP_Column, 0, 0, 1}, /* 6 */ - {OP_ResultRow, 1, 0, 0}, /* 7 */ - {OP_Goto, 0, 4, 0}, /* 8 */ - {OP_Close, 0, 0, 0}, /* 9 */ - {OP_Halt, 0, 0, 0}, /* 10 */ - }; - - int rc = SQLITE_OK; - char *zErr = 0; - Table *pTab; - Parse *pParse = 0; - Incrblob *pBlob = 0; - -#ifdef SQLITE_ENABLE_API_ARMOR - if( ppBlob==0 ){ - return SQLITE_MISUSE_BKPT; - } -#endif - *ppBlob = 0; -#ifdef SQLITE_ENABLE_API_ARMOR - if( !sqlite3SafetyCheckOk(db) || zTable==0 ){ - return SQLITE_MISUSE_BKPT; - } -#endif - flags = !!flags; /* flags = (flags ? 1 : 0); */ - - sqlite3_mutex_enter(db->mutex); - - pBlob = (Incrblob *)sqlite3DbMallocZero(db, sizeof(Incrblob)); - if( !pBlob ) goto blob_open_out; - pParse = sqlite3StackAllocRaw(db, sizeof(*pParse)); - if( !pParse ) goto blob_open_out; - - do { - memset(pParse, 0, sizeof(Parse)); - pParse->db = db; - sqlite3DbFree(db, zErr); - zErr = 0; - - sqlite3BtreeEnterAll(db); - pTab = sqlite3LocateTable(pParse, 0, zTable, zDb); - if( pTab && IsVirtual(pTab) ){ - pTab = 0; - sqlite3ErrorMsg(pParse, "cannot open virtual table: %s", zTable); - } - if( pTab && !HasRowid(pTab) ){ - pTab = 0; - sqlite3ErrorMsg(pParse, "cannot open table without rowid: %s", zTable); - } -#ifndef SQLITE_OMIT_VIEW - if( pTab && pTab->pSelect ){ - pTab = 0; - sqlite3ErrorMsg(pParse, "cannot open view: %s", zTable); - } -#endif - if( !pTab ){ - if( pParse->zErrMsg ){ - sqlite3DbFree(db, zErr); - zErr = pParse->zErrMsg; - pParse->zErrMsg = 0; - } - rc = SQLITE_ERROR; - sqlite3BtreeLeaveAll(db); - goto blob_open_out; - } - - /* Now search pTab for the exact column. */ - for(iCol=0; iCol<pTab->nCol; iCol++) { - if( sqlite3StrICmp(pTab->aCol[iCol].zName, zColumn)==0 ){ - break; - } - } - if( iCol==pTab->nCol ){ - sqlite3DbFree(db, zErr); - zErr = sqlite3MPrintf(db, "no such column: \"%s\"", zColumn); - rc = SQLITE_ERROR; - sqlite3BtreeLeaveAll(db); - goto blob_open_out; - } - - /* If the value is being opened for writing, check that the - ** column is not indexed, and that it is not part of a foreign key. - ** It is against the rules to open a column to which either of these - ** descriptions applies for writing. */ - if( flags ){ - const char *zFault = 0; - Index *pIdx; -#ifndef SQLITE_OMIT_FOREIGN_KEY - if( db->flags&SQLITE_ForeignKeys ){ - /* Check that the column is not part of an FK child key definition. It - ** is not necessary to check if it is part of a parent key, as parent - ** key columns must be indexed. The check below will pick up this - ** case. */ - FKey *pFKey; - for(pFKey=pTab->pFKey; pFKey; pFKey=pFKey->pNextFrom){ - int j; - for(j=0; j<pFKey->nCol; j++){ - if( pFKey->aCol[j].iFrom==iCol ){ - zFault = "foreign key"; - } - } - } - } -#endif - for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){ - int j; - for(j=0; j<pIdx->nKeyCol; j++){ - /* FIXME: Be smarter about indexes that use expressions */ - if( pIdx->aiColumn[j]==iCol || pIdx->aiColumn[j]==XN_EXPR ){ - zFault = "indexed"; - } - } - } - if( zFault ){ - sqlite3DbFree(db, zErr); - zErr = sqlite3MPrintf(db, "cannot open %s column for writing", zFault); - rc = SQLITE_ERROR; - sqlite3BtreeLeaveAll(db); - goto blob_open_out; - } - } - - pBlob->pStmt = (sqlite3_stmt *)sqlite3VdbeCreate(pParse); - assert( pBlob->pStmt || db->mallocFailed ); - if( pBlob->pStmt ){ - Vdbe *v = (Vdbe *)pBlob->pStmt; - int iDb = sqlite3SchemaToIndex(db, pTab->pSchema); - - - sqlite3VdbeAddOp4Int(v, OP_Transaction, iDb, flags, - pTab->pSchema->schema_cookie, - pTab->pSchema->iGeneration); - sqlite3VdbeChangeP5(v, 1); - sqlite3VdbeAddOpList(v, ArraySize(openBlob), openBlob, iLn); - - /* Make sure a mutex is held on the table to be accessed */ - sqlite3VdbeUsesBtree(v, iDb); - - /* Configure the OP_TableLock instruction */ -#ifdef SQLITE_OMIT_SHARED_CACHE - sqlite3VdbeChangeToNoop(v, 1); -#else - sqlite3VdbeChangeP1(v, 1, iDb); - sqlite3VdbeChangeP2(v, 1, pTab->tnum); - sqlite3VdbeChangeP3(v, 1, flags); - sqlite3VdbeChangeP4(v, 1, pTab->zName, P4_TRANSIENT); -#endif - - /* Remove either the OP_OpenWrite or OpenRead. Set the P2 - ** parameter of the other to pTab->tnum. */ - sqlite3VdbeChangeToNoop(v, 3 - flags); - sqlite3VdbeChangeP2(v, 2 + flags, pTab->tnum); - sqlite3VdbeChangeP3(v, 2 + flags, iDb); - - /* Configure the number of columns. Configure the cursor to - ** think that the table has one more column than it really - ** does. An OP_Column to retrieve this imaginary column will - ** always return an SQL NULL. This is useful because it means - ** we can invoke OP_Column to fill in the vdbe cursors type - ** and offset cache without causing any IO. - */ - sqlite3VdbeChangeP4(v, 2+flags, SQLITE_INT_TO_PTR(pTab->nCol+1),P4_INT32); - sqlite3VdbeChangeP2(v, 6, pTab->nCol); - if( !db->mallocFailed ){ - pParse->nVar = 1; - pParse->nMem = 1; - pParse->nTab = 1; - sqlite3VdbeMakeReady(v, pParse); - } - } - - pBlob->flags = flags; - pBlob->iCol = iCol; - pBlob->db = db; - sqlite3BtreeLeaveAll(db); - if( db->mallocFailed ){ - goto blob_open_out; - } - sqlite3_bind_int64(pBlob->pStmt, 1, iRow); - rc = blobSeekToRow(pBlob, iRow, &zErr); - } while( (++nAttempt)<SQLITE_MAX_SCHEMA_RETRY && rc==SQLITE_SCHEMA ); - -blob_open_out: - if( rc==SQLITE_OK && db->mallocFailed==0 ){ - *ppBlob = (sqlite3_blob *)pBlob; - }else{ - if( pBlob && pBlob->pStmt ) sqlite3VdbeFinalize((Vdbe *)pBlob->pStmt); - sqlite3DbFree(db, pBlob); - } - sqlite3ErrorWithMsg(db, rc, (zErr ? "%s" : 0), zErr); - sqlite3DbFree(db, zErr); - sqlite3ParserReset(pParse); - sqlite3StackFree(db, pParse); - rc = sqlite3ApiExit(db, rc); - sqlite3_mutex_leave(db->mutex); - return rc; -} - -/* -** Close a blob handle that was previously created using -** sqlite3_blob_open(). -*/ -int sqlite3_blob_close(sqlite3_blob *pBlob){ - Incrblob *p = (Incrblob *)pBlob; - int rc; - sqlite3 *db; - - if( p ){ - db = p->db; - sqlite3_mutex_enter(db->mutex); - rc = sqlite3_finalize(p->pStmt); - sqlite3DbFree(db, p); - sqlite3_mutex_leave(db->mutex); - }else{ - rc = SQLITE_OK; - } - return rc; -} - -/* -** Perform a read or write operation on a blob -*/ -static int blobReadWrite( - sqlite3_blob *pBlob, - void *z, - int n, - int iOffset, - int (*xCall)(BtCursor*, u32, u32, void*) -){ - int rc; - Incrblob *p = (Incrblob *)pBlob; - Vdbe *v; - sqlite3 *db; - - if( p==0 ) return SQLITE_MISUSE_BKPT; - db = p->db; - sqlite3_mutex_enter(db->mutex); - v = (Vdbe*)p->pStmt; - - if( n<0 || iOffset<0 || ((sqlite3_int64)iOffset+n)>p->nByte ){ - /* Request is out of range. Return a transient error. */ - rc = SQLITE_ERROR; - }else if( v==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{ - /* Call either BtreeData() or BtreePutData(). If SQLITE_ABORT is - ** returned, clean-up the statement handle. - */ - assert( db == v->db ); - sqlite3BtreeEnterCursor(p->pCsr); - rc = xCall(p->pCsr, iOffset+p->iOffset, n, z); - sqlite3BtreeLeaveCursor(p->pCsr); - if( rc==SQLITE_ABORT ){ - sqlite3VdbeFinalize(v); - p->pStmt = 0; - }else{ - v->rc = rc; - } - } - sqlite3Error(db, rc); - rc = sqlite3ApiExit(db, rc); - sqlite3_mutex_leave(db->mutex); - return rc; -} - -/* -** Read data from a blob handle. -*/ -int sqlite3_blob_read(sqlite3_blob *pBlob, void *z, int n, int iOffset){ - return blobReadWrite(pBlob, z, n, iOffset, sqlite3BtreeData); -} - -/* -** Write data to a blob handle. -*/ -int sqlite3_blob_write(sqlite3_blob *pBlob, const void *z, int n, int iOffset){ - return blobReadWrite(pBlob, (void *)z, n, iOffset, sqlite3BtreePutData); -} - -/* -** Query a blob handle for the size of the data. -** -** The Incrblob.nByte field is fixed for the lifetime of the Incrblob -** so no mutex is required for access. -*/ -int sqlite3_blob_bytes(sqlite3_blob *pBlob){ - Incrblob *p = (Incrblob *)pBlob; - return (p && p->pStmt) ? 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 ){ - sqlite3ErrorWithMsg(db, rc, (zErr ? "%s" : 0), zErr); - sqlite3DbFree(db, zErr); - } - assert( rc!=SQLITE_SCHEMA ); - } - - rc = sqlite3ApiExit(db, rc); - assert( rc==SQLITE_OK || p->pStmt==0 ); - sqlite3_mutex_leave(db->mutex); - return rc; -} - -#endif /* #ifndef SQLITE_OMIT_INCRBLOB */ |