engine/sqlite/src/attach.cpp
changeset 71 fbd95db6a4e1
parent 69 4a65cc85c4f3
child 72 2e267e7da513
--- a/engine/sqlite/src/attach.cpp	Wed Apr 28 13:20:05 2010 +0100
+++ /dev/null	Thu Jan 01 00:00:00 1970 +0000
@@ -1,521 +0,0 @@
-/*
-** 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.
-**
-** $Id: attach.cpp 1282 2008-11-13 09:31:33Z LarsPson $
-*/
-#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 = sqlite3ExprResolveNames(pName, pExpr);
-      if( rc==SQLITE_OK && !sqlite3ExprIsConstant(pExpr) ){
-        sqlite3ErrorMsg(pName->pParse, "invalid name: \"%T\"", &pExpr->span);
-        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 argc,
-  sqlite3_value **argv
-){
-  int i;
-  int rc = 0;
-  sqlite3 *db = (sqlite3 *)sqlite3_user_data(context);
-  const char *zName;
-  const char *zFile;
-  Db *aNew;
-  char *zErrDyn = 0;
-  char zErr[128];
-
-  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>=SQLITE_MAX_ATTACHED+2 ){
-    sqlite3_snprintf(
-      sizeof(zErr), zErr, "too many attached databases - max %d", 
-      SQLITE_MAX_ATTACHED
-    );
-    goto attach_error;
-  }
-  if( !db->autoCommit ){
-    sqlite3_snprintf(sizeof(zErr), zErr,
-                     "cannot ATTACH database within transaction");
-    goto attach_error;
-  }
-  for(i=0; i<db->nDb; i++){
-    char *z = db->aDb[i].zName;
-    if( z && zName && sqlite3StrICmp(z, zName)==0 ){
-      sqlite3_snprintf(sizeof(zErr), zErr, 
-                       "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 = (Db*)sqlite3_malloc( sizeof(db->aDb[0])*3 );
-    if( aNew==0 ){
-      db->mallocFailed = 1;
-      return;
-    }
-    memcpy(aNew, db->aDb, sizeof(db->aDb[0])*2);
-  }else{
-    aNew = (Db*)sqlite3_realloc(db->aDb, sizeof(db->aDb[0])*(db->nDb+1) );
-    if( aNew==0 ){
-      db->mallocFailed = 1;
-      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 = sqlite3BtreeFactory(db, zFile, 0, SQLITE_DEFAULT_CACHE_SIZE,
-                           db->openFlags | SQLITE_OPEN_MAIN_DB,
-                           &aNew->pBt);
-  if( rc==SQLITE_OK ){
-    aNew->pSchema = sqlite3SchemaGet(db, aNew->pBt);
-    if( !aNew->pSchema ){
-      rc = SQLITE_NOMEM;
-    }else if( aNew->pSchema->file_format && aNew->pSchema->enc!=ENC(db) ){
-      sqlite3_snprintf(sizeof(zErr), zErr, 
-        "attached databases must use the same text encoding as main database");
-      goto attach_error;
-    }
-    sqlite3PagerLockingMode(sqlite3BtreePager(aNew->pBt), db->dfltLockMode);
-  }
-  aNew->zName = sqlite3DbStrDup(db, zName);
-  aNew->safety_level = 3;
-
-#if SQLITE_HAS_CODEC
-  {
-    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]);
-        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);
-        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 ){
-    sqlite3SafetyOn(db);
-    rc = sqlite3Init(db, &zErrDyn);
-    sqlite3SafetyOff(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, 0);
-    db->nDb = iDb;
-    if( rc==SQLITE_NOMEM || rc==SQLITE_IOERR_NOMEM ){
-      db->mallocFailed = 1;
-      sqlite3_snprintf(sizeof(zErr),zErr, "out of memory");
-    }else{
-      sqlite3_snprintf(sizeof(zErr),zErr, "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);
-    sqlite3_free(zErrDyn);
-  }else{
-    zErr[sizeof(zErr)-1] = 0;
-    sqlite3_result_error(context, zErr, -1);
-  }
-}
-
-/*
-** 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 argc,
-  sqlite3_value **argv
-){
-  const char *zName = (const char *)sqlite3_value_text(argv[0]);
-  sqlite3 *db = (sqlite3 *)sqlite3_user_data(context);
-  int i;
-  Db *pDb = 0;
-  char zErr[128];
-
-  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) ){
-    sqlite3_snprintf(sizeof(zErr),zErr, "database %s is locked", zName);
-    goto detach_error;
-  }
-
-  sqlite3BtreeClose(pDb->pBt);
-  pDb->pBt = 0;
-  pDb->pSchema = 0;
-  sqlite3ResetInternalSchema(db, 0);
-  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 */
-  const char *zFunc,   /* Either "sqlite_attach" or "sqlite_detach */
-  int nFunc,           /* Number of args to pass to zFunc */
-  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;
-  FuncDef *pFunc;
-  sqlite3* db = pParse->db;
-
-#ifndef SQLITE_OMIT_AUTHORIZATION
-  assert( db->mallocFailed || pAuthArg );
-  if( pAuthArg ){
-    char *zAuthArg = sqlite3NameFromToken(db, &pAuthArg->span);
-    if( !zAuthArg ){
-      goto attach_end;
-    }
-    rc = sqlite3AuthCheck(pParse, type, zAuthArg, 0, 0);
-    sqlite3_free(zAuthArg);
-    if(rc!=SQLITE_OK ){
-      goto attach_end;
-    }
-  }
-#endif /* SQLITE_OMIT_AUTHORIZATION */
-
-  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;
-  }
-
-  v = sqlite3GetVdbe(pParse);
-  sqlite3ExprCode(pParse, pFilename);
-  sqlite3ExprCode(pParse, pDbname);
-  sqlite3ExprCode(pParse, pKey);
-
-  assert( v || db->mallocFailed );
-  if( v ){
-    sqlite3VdbeAddOp(v, OP_Function, 0, nFunc);
-    pFunc = sqlite3FindFunction(db, zFunc, strlen(zFunc), nFunc, SQLITE_UTF8,0);
-    sqlite3VdbeChangeP3(v, -1, (char *)pFunc, P3_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).
-    */
-    sqlite3VdbeAddOp(v, OP_Expire, (type==SQLITE_ATTACH), 0);
-  }
-  
-attach_end:
-  sqlite3ExprDelete(pFilename);
-  sqlite3ExprDelete(pDbname);
-  sqlite3ExprDelete(pKey);
-}
-
-/*
-** Called by the parser to compile a DETACH statement.
-**
-**     DETACH pDbname
-*/
-void sqlite3Detach(Parse *pParse, Expr *pDbname){
-  codeAttach(pParse, SQLITE_DETACH, "sqlite_detach", 1, 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){
-  codeAttach(pParse, SQLITE_ATTACH, "sqlite_attach", 3, p, p, pDbname, pKey);
-}
-#endif /* SQLITE_OMIT_ATTACH */
-
-/*
-** Register the functions sqlite_attach and sqlite_detach.
-*/
-void sqlite3AttachFunctions(sqlite3 *db){
-#ifndef SQLITE_OMIT_ATTACH
-  static const int enc = SQLITE_UTF8;
-  sqlite3CreateFunc(db, "sqlite_attach", 3, enc, db, attachFunc, 0, 0);
-  sqlite3CreateFunc(db, "sqlite_detach", 1, enc, db, detachFunc, 0, 0);
-#endif
-}
-
-/*
-** 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( 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;
-  SrcList::SrcList_item *pItem;
-
-  if( 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( sqlite3FixSelect(pFix, pExpr->pSelect) ){
-      return 1;
-    }
-    if( sqlite3FixExprList(pFix, pExpr->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;
-  ExprList::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