| /* |
| ** 2003 April 6 |
| ** |
| ** 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 the ATTACH and DETACH commands. |
| */ |
| #include "sqliteInt.h" |
| |
| #ifndef SQLITE_OMIT_ATTACH |
| /* |
| ** Resolve an expression that was part of an ATTACH or DETACH statement. This |
| ** is slightly different from resolving a normal SQL expression, because simple |
| ** identifiers are treated as strings, not possible column names or aliases. |
| ** |
| ** i.e. if the parser sees: |
| ** |
| ** ATTACH DATABASE abc AS def |
| ** |
| ** it treats the two expressions as literal strings 'abc' and 'def' instead of |
| ** looking for columns of the same name. |
| ** |
| ** This only applies to the root node of pExpr, so the statement: |
| ** |
| ** ATTACH DATABASE abc||def AS 'db2' |
| ** |
| ** will fail because neither abc or def can be resolved. |
| */ |
| static int resolveAttachExpr(NameContext *pName, Expr *pExpr) |
| { |
| int rc = SQLITE_OK; |
| if( pExpr ){ |
| if( pExpr->op!=TK_ID ){ |
| rc = sqlite3ResolveExprNames(pName, pExpr); |
| if( rc==SQLITE_OK && !sqlite3ExprIsConstant(pExpr) ){ |
| sqlite3ErrorMsg(pName->pParse, "invalid name: \"%s\"", pExpr->u.zToken); |
| return SQLITE_ERROR; |
| } |
| }else{ |
| pExpr->op = TK_STRING; |
| } |
| } |
| return rc; |
| } |
| |
| /* |
| ** An SQL user-function registered to do the work of an ATTACH statement. The |
| ** three arguments to the function come directly from an attach statement: |
| ** |
| ** ATTACH DATABASE x AS y KEY z |
| ** |
| ** SELECT sqlite_attach(x, y, z) |
| ** |
| ** If the optional "KEY z" syntax is omitted, an SQL NULL is passed as the |
| ** third argument. |
| */ |
| static void attachFunc( |
| sqlite3_context *context, |
| int NotUsed, |
| sqlite3_value **argv |
| ){ |
| int i; |
| int rc = 0; |
| sqlite3 *db = sqlite3_context_db_handle(context); |
| const char *zName; |
| const char *zFile; |
| Db *aNew; |
| char *zErrDyn = 0; |
| |
| UNUSED_PARAMETER(NotUsed); |
| |
| zFile = (const char *)sqlite3_value_text(argv[0]); |
| zName = (const char *)sqlite3_value_text(argv[1]); |
| if( zFile==0 ) zFile = ""; |
| if( zName==0 ) zName = ""; |
| |
| /* Check for the following errors: |
| ** |
| ** * Too many attached databases, |
| ** * Transaction currently open |
| ** * Specified database name already being used. |
| */ |
| if( db->nDb>=db->aLimit[SQLITE_LIMIT_ATTACHED]+2 ){ |
| zErrDyn = sqlite3MPrintf(db, "too many attached databases - max %d", |
| db->aLimit[SQLITE_LIMIT_ATTACHED] |
| ); |
| goto attach_error; |
| } |
| if( !db->autoCommit ){ |
| zErrDyn = sqlite3MPrintf(db, "cannot ATTACH database within transaction"); |
| goto attach_error; |
| } |
| for(i=0; i<db->nDb; i++){ |
| char *z = db->aDb[i].zName; |
| assert( z && zName ); |
| if( sqlite3StrICmp(z, zName)==0 ){ |
| zErrDyn = sqlite3MPrintf(db, "database %s is already in use", zName); |
| goto attach_error; |
| } |
| } |
| |
| /* Allocate the new entry in the db->aDb[] array and initialise the schema |
| ** hash tables. |
| */ |
| if( db->aDb==db->aDbStatic ){ |
| aNew = sqlite3DbMallocRaw(db, sizeof(db->aDb[0])*3 ); |
| if( aNew==0 ) return; |
| memcpy(aNew, db->aDb, sizeof(db->aDb[0])*2); |
| }else{ |
| aNew = sqlite3DbRealloc(db, db->aDb, sizeof(db->aDb[0])*(db->nDb+1) ); |
| if( aNew==0 ) return; |
| } |
| db->aDb = aNew; |
| aNew = &db->aDb[db->nDb]; |
| memset(aNew, 0, sizeof(*aNew)); |
| |
| /* Open the database file. If the btree is successfully opened, use |
| ** it to obtain the database schema. At this point the schema may |
| ** or may not be initialised. |
| */ |
| rc = sqlite3BtreeOpen(zFile, db, &aNew->pBt, 0, |
| db->openFlags | SQLITE_OPEN_MAIN_DB); |
| db->nDb++; |
| if( rc==SQLITE_CONSTRAINT ){ |
| rc = SQLITE_ERROR; |
| zErrDyn = sqlite3MPrintf(db, "database is already attached"); |
| }else if( rc==SQLITE_OK ){ |
| Pager *pPager; |
| aNew->pSchema = sqlite3SchemaGet(db, aNew->pBt); |
| if( !aNew->pSchema ){ |
| rc = SQLITE_NOMEM; |
| }else if( aNew->pSchema->file_format && aNew->pSchema->enc!=ENC(db) ){ |
| zErrDyn = sqlite3MPrintf(db, |
| "attached databases must use the same text encoding as main database"); |
| rc = SQLITE_ERROR; |
| } |
| pPager = sqlite3BtreePager(aNew->pBt); |
| sqlite3PagerLockingMode(pPager, db->dfltLockMode); |
| sqlite3BtreeSecureDelete(aNew->pBt, |
| sqlite3BtreeSecureDelete(db->aDb[0].pBt,-1) ); |
| } |
| aNew->safety_level = 3; |
| aNew->zName = sqlite3DbStrDup(db, zName); |
| if( rc==SQLITE_OK && aNew->zName==0 ){ |
| rc = SQLITE_NOMEM; |
| } |
| |
| |
| #ifdef SQLITE_HAS_CODEC |
| if( rc==SQLITE_OK ){ |
| extern int sqlite3CodecAttach(sqlite3*, int, const void*, int); |
| extern void sqlite3CodecGetKey(sqlite3*, int, void**, int*); |
| int nKey; |
| char *zKey; |
| int t = sqlite3_value_type(argv[2]); |
| switch( t ){ |
| case SQLITE_INTEGER: |
| case SQLITE_FLOAT: |
| zErrDyn = sqlite3DbStrDup(db, "Invalid key value"); |
| rc = SQLITE_ERROR; |
| break; |
| |
| case SQLITE_TEXT: |
| case SQLITE_BLOB: |
| nKey = sqlite3_value_bytes(argv[2]); |
| zKey = (char *)sqlite3_value_blob(argv[2]); |
| rc = sqlite3CodecAttach(db, db->nDb-1, zKey, nKey); |
| break; |
| |
| case SQLITE_NULL: |
| /* No key specified. Use the key from the main database */ |
| sqlite3CodecGetKey(db, 0, (void**)&zKey, &nKey); |
| if( nKey>0 || sqlite3BtreeGetReserve(db->aDb[0].pBt)>0 ){ |
| rc = sqlite3CodecAttach(db, db->nDb-1, zKey, nKey); |
| } |
| break; |
| } |
| } |
| #endif |
| |
| /* If the file was opened successfully, read the schema for the new database. |
| ** If this fails, or if opening the file failed, then close the file and |
| ** remove the entry from the db->aDb[] array. i.e. put everything back the way |
| ** we found it. |
| */ |
| if( rc==SQLITE_OK ){ |
| sqlite3BtreeEnterAll(db); |
| rc = sqlite3Init(db, &zErrDyn); |
| sqlite3BtreeLeaveAll(db); |
| } |
| if( rc ){ |
| int iDb = db->nDb - 1; |
| assert( iDb>=2 ); |
| if( db->aDb[iDb].pBt ){ |
| sqlite3BtreeClose(db->aDb[iDb].pBt); |
| db->aDb[iDb].pBt = 0; |
| db->aDb[iDb].pSchema = 0; |
| } |
| sqlite3ResetInternalSchema(db, -1); |
| db->nDb = iDb; |
| if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){ |
| db->mallocFailed = 1; |
| sqlite3DbFree(db, zErrDyn); |
| zErrDyn = sqlite3MPrintf(db, "out of memory"); |
| }else if( zErrDyn==0 ){ |
| zErrDyn = sqlite3MPrintf(db, "unable to open database: %s", zFile); |
| } |
| goto attach_error; |
| } |
| |
| return; |
| |
| attach_error: |
| /* Return an error if we get here */ |
| if( zErrDyn ){ |
| sqlite3_result_error(context, zErrDyn, -1); |
| sqlite3DbFree(db, zErrDyn); |
| } |
| if( rc ) sqlite3_result_error_code(context, rc); |
| } |
| |
| /* |
| ** An SQL user-function registered to do the work of an DETACH statement. The |
| ** three arguments to the function come directly from a detach statement: |
| ** |
| ** DETACH DATABASE x |
| ** |
| ** SELECT sqlite_detach(x) |
| */ |
| static void detachFunc( |
| sqlite3_context *context, |
| int NotUsed, |
| sqlite3_value **argv |
| ){ |
| const char *zName = (const char *)sqlite3_value_text(argv[0]); |
| sqlite3 *db = sqlite3_context_db_handle(context); |
| int i; |
| Db *pDb = 0; |
| char zErr[128]; |
| |
| UNUSED_PARAMETER(NotUsed); |
| |
| if( zName==0 ) zName = ""; |
| for(i=0; i<db->nDb; i++){ |
| pDb = &db->aDb[i]; |
| if( pDb->pBt==0 ) continue; |
| if( sqlite3StrICmp(pDb->zName, zName)==0 ) break; |
| } |
| |
| if( i>=db->nDb ){ |
| sqlite3_snprintf(sizeof(zErr),zErr, "no such database: %s", zName); |
| goto detach_error; |
| } |
| if( i<2 ){ |
| sqlite3_snprintf(sizeof(zErr),zErr, "cannot detach database %s", zName); |
| goto detach_error; |
| } |
| if( !db->autoCommit ){ |
| sqlite3_snprintf(sizeof(zErr), zErr, |
| "cannot DETACH database within transaction"); |
| goto detach_error; |
| } |
| if( sqlite3BtreeIsInReadTrans(pDb->pBt) || sqlite3BtreeIsInBackup(pDb->pBt) ){ |
| sqlite3_snprintf(sizeof(zErr),zErr, "database %s is locked", zName); |
| goto detach_error; |
| } |
| |
| sqlite3BtreeClose(pDb->pBt); |
| pDb->pBt = 0; |
| pDb->pSchema = 0; |
| sqlite3ResetInternalSchema(db, -1); |
| return; |
| |
| detach_error: |
| sqlite3_result_error(context, zErr, -1); |
| } |
| |
| /* |
| ** This procedure generates VDBE code for a single invocation of either the |
| ** sqlite_detach() or sqlite_attach() SQL user functions. |
| */ |
| static void codeAttach( |
| Parse *pParse, /* The parser context */ |
| int type, /* Either SQLITE_ATTACH or SQLITE_DETACH */ |
| FuncDef const *pFunc,/* FuncDef wrapper for detachFunc() or attachFunc() */ |
| Expr *pAuthArg, /* Expression to pass to authorization callback */ |
| Expr *pFilename, /* Name of database file */ |
| Expr *pDbname, /* Name of the database to use internally */ |
| Expr *pKey /* Database key for encryption extension */ |
| ){ |
| int rc; |
| NameContext sName; |
| Vdbe *v; |
| sqlite3* db = pParse->db; |
| int regArgs; |
| |
| memset(&sName, 0, sizeof(NameContext)); |
| sName.pParse = pParse; |
| |
| if( |
| SQLITE_OK!=(rc = resolveAttachExpr(&sName, pFilename)) || |
| SQLITE_OK!=(rc = resolveAttachExpr(&sName, pDbname)) || |
| SQLITE_OK!=(rc = resolveAttachExpr(&sName, pKey)) |
| ){ |
| pParse->nErr++; |
| goto attach_end; |
| } |
| |
| #ifndef SQLITE_OMIT_AUTHORIZATION |
| if( pAuthArg ){ |
| char *zAuthArg; |
| if( pAuthArg->op==TK_STRING ){ |
| zAuthArg = pAuthArg->u.zToken; |
| }else{ |
| zAuthArg = 0; |
| } |
| rc = sqlite3AuthCheck(pParse, type, zAuthArg, 0, 0); |
| if(rc!=SQLITE_OK ){ |
| goto attach_end; |
| } |
| } |
| #endif /* SQLITE_OMIT_AUTHORIZATION */ |
| |
| |
| v = sqlite3GetVdbe(pParse); |
| regArgs = sqlite3GetTempRange(pParse, 4); |
| sqlite3ExprCode(pParse, pFilename, regArgs); |
| sqlite3ExprCode(pParse, pDbname, regArgs+1); |
| sqlite3ExprCode(pParse, pKey, regArgs+2); |
| |
| assert( v || db->mallocFailed ); |
| if( v ){ |
| sqlite3VdbeAddOp3(v, OP_Function, 0, regArgs+3-pFunc->nArg, regArgs+3); |
| assert( pFunc->nArg==-1 || (pFunc->nArg&0xff)==pFunc->nArg ); |
| sqlite3VdbeChangeP5(v, (u8)(pFunc->nArg)); |
| sqlite3VdbeChangeP4(v, -1, (char *)pFunc, P4_FUNCDEF); |
| |
| /* Code an OP_Expire. For an ATTACH statement, set P1 to true (expire this |
| ** statement only). For DETACH, set it to false (expire all existing |
| ** statements). |
| */ |
| sqlite3VdbeAddOp1(v, OP_Expire, (type==SQLITE_ATTACH)); |
| } |
| |
| attach_end: |
| sqlite3ExprDelete(db, pFilename); |
| sqlite3ExprDelete(db, pDbname); |
| sqlite3ExprDelete(db, pKey); |
| } |
| |
| /* |
| ** Called by the parser to compile a DETACH statement. |
| ** |
| ** DETACH pDbname |
| */ |
| void sqlite3Detach(Parse *pParse, Expr *pDbname){ |
| static const FuncDef detach_func = { |
| 1, /* nArg */ |
| SQLITE_UTF8, /* iPrefEnc */ |
| 0, /* flags */ |
| 0, /* pUserData */ |
| 0, /* pNext */ |
| detachFunc, /* xFunc */ |
| 0, /* xStep */ |
| 0, /* xFinalize */ |
| "sqlite_detach", /* zName */ |
| 0, /* pHash */ |
| 0 /* pDestructor */ |
| }; |
| codeAttach(pParse, SQLITE_DETACH, &detach_func, pDbname, 0, 0, pDbname); |
| } |
| |
| /* |
| ** Called by the parser to compile an ATTACH statement. |
| ** |
| ** ATTACH p AS pDbname KEY pKey |
| */ |
| void sqlite3Attach(Parse *pParse, Expr *p, Expr *pDbname, Expr *pKey){ |
| static const FuncDef attach_func = { |
| 3, /* nArg */ |
| SQLITE_UTF8, /* iPrefEnc */ |
| 0, /* flags */ |
| 0, /* pUserData */ |
| 0, /* pNext */ |
| attachFunc, /* xFunc */ |
| 0, /* xStep */ |
| 0, /* xFinalize */ |
| "sqlite_attach", /* zName */ |
| 0, /* pHash */ |
| 0 /* pDestructor */ |
| }; |
| codeAttach(pParse, SQLITE_ATTACH, &attach_func, p, p, pDbname, pKey); |
| } |
| #endif /* SQLITE_OMIT_ATTACH */ |
| |
| /* |
| ** Initialize a DbFixer structure. This routine must be called prior |
| ** to passing the structure to one of the sqliteFixAAAA() routines below. |
| ** |
| ** The return value indicates whether or not fixation is required. TRUE |
| ** means we do need to fix the database references, FALSE means we do not. |
| */ |
| int sqlite3FixInit( |
| DbFixer *pFix, /* The fixer to be initialized */ |
| Parse *pParse, /* Error messages will be written here */ |
| int iDb, /* This is the database that must be used */ |
| const char *zType, /* "view", "trigger", or "index" */ |
| const Token *pName /* Name of the view, trigger, or index */ |
| ){ |
| sqlite3 *db; |
| |
| if( NEVER(iDb<0) || iDb==1 ) return 0; |
| db = pParse->db; |
| assert( db->nDb>iDb ); |
| pFix->pParse = pParse; |
| pFix->zDb = db->aDb[iDb].zName; |
| pFix->zType = zType; |
| pFix->pName = pName; |
| return 1; |
| } |
| |
| /* |
| ** The following set of routines walk through the parse tree and assign |
| ** a specific database to all table references where the database name |
| ** was left unspecified in the original SQL statement. The pFix structure |
| ** must have been initialized by a prior call to sqlite3FixInit(). |
| ** |
| ** These routines are used to make sure that an index, trigger, or |
| ** view in one database does not refer to objects in a different database. |
| ** (Exception: indices, triggers, and views in the TEMP database are |
| ** allowed to refer to anything.) If a reference is explicitly made |
| ** to an object in a different database, an error message is added to |
| ** pParse->zErrMsg and these routines return non-zero. If everything |
| ** checks out, these routines return 0. |
| */ |
| int sqlite3FixSrcList( |
| DbFixer *pFix, /* Context of the fixation */ |
| SrcList *pList /* The Source list to check and modify */ |
| ){ |
| int i; |
| const char *zDb; |
| struct SrcList_item *pItem; |
| |
| if( NEVER(pList==0) ) return 0; |
| zDb = pFix->zDb; |
| for(i=0, pItem=pList->a; i<pList->nSrc; i++, pItem++){ |
| if( pItem->zDatabase==0 ){ |
| pItem->zDatabase = sqlite3DbStrDup(pFix->pParse->db, zDb); |
| }else if( sqlite3StrICmp(pItem->zDatabase,zDb)!=0 ){ |
| sqlite3ErrorMsg(pFix->pParse, |
| "%s %T cannot reference objects in database %s", |
| pFix->zType, pFix->pName, pItem->zDatabase); |
| return 1; |
| } |
| #if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER) |
| if( sqlite3FixSelect(pFix, pItem->pSelect) ) return 1; |
| if( sqlite3FixExpr(pFix, pItem->pOn) ) return 1; |
| #endif |
| } |
| return 0; |
| } |
| #if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER) |
| int sqlite3FixSelect( |
| DbFixer *pFix, /* Context of the fixation */ |
| Select *pSelect /* The SELECT statement to be fixed to one database */ |
| ){ |
| while( pSelect ){ |
| if( sqlite3FixExprList(pFix, pSelect->pEList) ){ |
| return 1; |
| } |
| if( sqlite3FixSrcList(pFix, pSelect->pSrc) ){ |
| return 1; |
| } |
| if( sqlite3FixExpr(pFix, pSelect->pWhere) ){ |
| return 1; |
| } |
| if( sqlite3FixExpr(pFix, pSelect->pHaving) ){ |
| return 1; |
| } |
| pSelect = pSelect->pPrior; |
| } |
| return 0; |
| } |
| int sqlite3FixExpr( |
| DbFixer *pFix, /* Context of the fixation */ |
| Expr *pExpr /* The expression to be fixed to one database */ |
| ){ |
| while( pExpr ){ |
| if( ExprHasAnyProperty(pExpr, EP_TokenOnly) ) break; |
| if( ExprHasProperty(pExpr, EP_xIsSelect) ){ |
| if( sqlite3FixSelect(pFix, pExpr->x.pSelect) ) return 1; |
| }else{ |
| if( sqlite3FixExprList(pFix, pExpr->x.pList) ) return 1; |
| } |
| if( sqlite3FixExpr(pFix, pExpr->pRight) ){ |
| return 1; |
| } |
| pExpr = pExpr->pLeft; |
| } |
| return 0; |
| } |
| int sqlite3FixExprList( |
| DbFixer *pFix, /* Context of the fixation */ |
| ExprList *pList /* The expression to be fixed to one database */ |
| ){ |
| int i; |
| struct ExprList_item *pItem; |
| if( pList==0 ) return 0; |
| for(i=0, pItem=pList->a; i<pList->nExpr; i++, pItem++){ |
| if( sqlite3FixExpr(pFix, pItem->pExpr) ){ |
| return 1; |
| } |
| } |
| return 0; |
| } |
| #endif |
| |
| #ifndef SQLITE_OMIT_TRIGGER |
| int sqlite3FixTriggerStep( |
| DbFixer *pFix, /* Context of the fixation */ |
| TriggerStep *pStep /* The trigger step be fixed to one database */ |
| ){ |
| while( pStep ){ |
| if( sqlite3FixSelect(pFix, pStep->pSelect) ){ |
| return 1; |
| } |
| if( sqlite3FixExpr(pFix, pStep->pWhere) ){ |
| return 1; |
| } |
| if( sqlite3FixExprList(pFix, pStep->pExprList) ){ |
| return 1; |
| } |
| pStep = pStep->pNext; |
| } |
| return 0; |
| } |
| #endif |