Get the temp_store and default_temp_store pragmas working. Update the

documentation.  Also fix a malloc problem that popped up during the regression
testing. (CVS 1302)

FossilOrigin-Name: 7ace576215367101904677bd69951755ee9cb1a1

5 files changed, 84 insertions, 27 deletions

diff --git a/src/build.c b/src/build.c
index 87c88346b..3d74322b3 100644
--- a/src/build.c
+++ b/src/build.c
@@ -23,7 +23,7 @@
 **     ROLLBACK
 **     PRAGMA
 **
-** $Id: build.c,v 1.175 2004/02/24 01:04:12 drh Exp $
+** $Id: build.c,v 1.176 2004/04/23 17:04:44 drh Exp $
 */
 #include "sqliteInt.h"
 #include <ctype.h>
@@ -484,7 +484,6 @@ void sqliteStartTable(
       if( rc!=SQLITE_OK ){
         sqliteErrorMsg(pParse, "unable to get a write lock on "
           "the temporary database file");
-        pParse->nErr++;
         return;
       }
     }
diff --git a/src/expr.c b/src/expr.c
index eafc50ce8..f92dbc078 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -12,7 +12,7 @@
 ** This file contains routines used for analyzing expressions and
 ** for generating VDBE code that evaluates expressions in SQLite.
 **
-** $Id: expr.c,v 1.113 2004/03/17 23:32:08 drh Exp $
+** $Id: expr.c,v 1.114 2004/04/23 17:04:45 drh Exp $
 */
 #include "sqliteInt.h"
 #include <ctype.h>
@@ -155,7 +155,8 @@ ExprList *sqliteExprListDup(ExprList *p){
   if( pNew==0 ) return 0;
   pNew->nExpr = pNew->nAlloc = p->nExpr;
   pNew->a = pItem = sqliteMalloc( p->nExpr*sizeof(p->a[0]) );
-  for(i=0; pItem && i<p->nExpr; i++, pItem++){
+  if( pItem==0 ) return 0;  /* Leaks memory after a malloc failure */
+  for(i=0; i<p->nExpr; i++, pItem++){
     Expr *pNewExpr, *pOldExpr;
     pItem->pExpr = pNewExpr = sqliteExprDup(pOldExpr = p->a[i].pExpr);
     if( pOldExpr->span.z!=0 && pNewExpr ){
@@ -278,6 +279,8 @@ ExprList *sqliteExprListAppend(ExprList *pList, Expr *pExpr, Token *pName){
 void sqliteExprListDelete(ExprList *pList){
   int i;
   if( pList==0 ) return;
+  assert( pList->a!=0 || (pList->nExpr==0 && pList->nAlloc==0) );
+  assert( pList->nExpr<=pList->nAlloc );
   for(i=0; i<pList->nExpr; i++){
     sqliteExprDelete(pList->a[i].pExpr);
     sqliteFree(pList->a[i].zName);
diff --git a/src/main.c b/src/main.c
index bf8b66673..27f237f7c 100644
--- a/src/main.c
+++ b/src/main.c
@@ -14,7 +14,7 @@
 ** other files are for internal use by SQLite and should not be
 ** accessed by users of the library.
 **
-** $Id: main.c,v 1.163 2004/03/17 18:44:47 drh Exp $
+** $Id: main.c,v 1.164 2004/04/23 17:04:45 drh Exp $
 */
 #include "sqliteInt.h"
 #include "os.h"
@@ -300,6 +300,9 @@ static int sqliteInitOne(sqlite *db, int iDb, char **pzErrMsg){
     if( size==0 ){ size = MAX_PAGES; }
     db->cache_size = size;
     db->safety_level = meta[4];
+    if( meta[6]>0 && meta[6]<=2 && db->temp_store==0 ){
+      db->temp_store = meta[6];
+    }
     if( db->safety_level==0 ) db->safety_level = 2;
 
     /*
diff --git a/src/pragma.c b/src/pragma.c
index d9cf6354a..a002c7dc2 100644
--- a/src/pragma.c
+++ b/src/pragma.c
@@ -11,7 +11,7 @@
 *************************************************************************
 ** This file contains code used to implement the PRAGMA command.
 **
-** $Id: pragma.c,v 1.18 2004/02/22 20:05:01 drh Exp $
+** $Id: pragma.c,v 1.19 2004/04/23 17:04:45 drh Exp $
 */
 #include "sqliteInt.h"
 #include <ctype.h>
@@ -71,8 +71,8 @@ static int getSafetyLevel(char *z){
 ** backed temporary databases, 2 for the Red-Black tree in memory database
 ** and 0 to use the compile-time default.
 */
-static int getTempStore(char *z){
-  if( z[0]>='0' || z[0]<='2' ){
+static int getTempStore(const char *z){
+  if( z[0]>='0' && z[0]<='2' ){
     return z[0] - '0';
   }else if( sqliteStrICmp(z, "file")==0 ){
     return 1;
@@ -84,6 +84,29 @@ static int getTempStore(char *z){
 }
 
 /*
+** If the TEMP database is open, close it and mark the database schema
+** as needing reloading.  This must be done when using the TEMP_STORE
+** or DEFAULT_TEMP_STORE pragmas.
+*/
+static int changeTempStorage(Parse *pParse, const char *zStorageType){
+  int ts = getTempStore(zStorageType);
+  sqlite *db = pParse->db;
+  if( db->temp_store==ts ) return SQLITE_OK;
+  if( db->aDb[1].pBt!=0 ){
+    if( db->flags & SQLITE_InTrans ){
+      sqliteErrorMsg(pParse, "temporary storage cannot be changed "
+        "from within a transaction");
+      return SQLITE_ERROR;
+    }
+    sqliteBtreeClose(db->aDb[1].pBt);
+    db->aDb[1].pBt = 0;
+    sqliteResetInternalSchema(db, 0);
+  }
+  db->temp_store = ts;
+  return SQLITE_OK;
+}
+
+/*
 ** Check to see if zRight and zLeft refer to a pragma that queries
 ** or changes one of the flags in db->flags.  Return 1 if so and 0 if not.
 ** Also, implement the pragma.
@@ -498,12 +521,7 @@ void sqlitePragma(Parse *pParse, Token *pLeft, Token *pRight, int minusFlag){
       sqliteVdbeAddOp(v, OP_Integer, db->temp_store, 0);
       sqliteVdbeAddOpList(v, ArraySize(getTmpDbLoc), getTmpDbLoc);
     }else{
-      if (&db->aDb[1].pBt != 0) {
-	sqliteErrorMsg(pParse, "The temporary database already exists - "
-          "its location cannot now be changed");
-      } else {
-	db->temp_store = getTempStore(zRight);
-      }
+      changeTempStorage(pParse, zRight);
     }
   }else
 
@@ -511,8 +529,9 @@ void sqlitePragma(Parse *pParse, Token *pLeft, Token *pRight, int minusFlag){
   **   PRAGMA default_temp_store
   **   PRAGMA default_temp_store = "default"|"memory"|"file"
   **
-  ** Return or set the value of the persistent temp_store flag (as
-  ** well as the value currently in force).
+  ** Return or set the value of the persistent temp_store flag.  Any
+  ** change does not take effect until the next time the database is
+  ** opened.
   **
   ** Note that it is possible for the library compile-time options to
   ** override this setting
@@ -525,16 +544,10 @@ void sqlitePragma(Parse *pParse, Token *pLeft, Token *pRight, int minusFlag){
     if( pRight->z==pLeft->z ){
       sqliteVdbeAddOpList(v, ArraySize(getTmpDbLoc), getTmpDbLoc);
     }else{
-      if (&db->aDb[1].pBt != 0) {
-	sqliteErrorMsg(pParse, "The temporary database already exists - "
-            "its location cannot now be changed");
-      } else {
-	sqliteBeginWriteOperation(pParse, 0, 0);
-	db->temp_store = getTempStore(zRight);
-	sqliteVdbeAddOp(v, OP_Integer, db->temp_store, 0);
-	sqliteVdbeAddOp(v, OP_SetCookie, 0, 5);
-	sqliteEndWriteOperation(pParse);
-      }
+      sqliteBeginWriteOperation(pParse, 0, 0);
+      sqliteVdbeAddOp(v, OP_Integer, getTempStore(zRight), 0);
+      sqliteVdbeAddOp(v, OP_SetCookie, 0, 5);
+      sqliteEndWriteOperation(pParse);
     }
   }else
 
diff --git a/src/test4.c b/src/test4.c
index 3389f3eae..2966a6756 100644
--- a/src/test4.c
+++ b/src/test4.c
@@ -11,7 +11,7 @@
 *************************************************************************
 ** Code for testing the the SQLite library in a multithreaded environment.
 **
-** $Id: test4.c,v 1.2 2003/12/20 04:00:53 drh Exp $
+** $Id: test4.c,v 1.3 2004/04/23 17:04:45 drh Exp $
 */
 #include "sqliteInt.h"
 #include "tcl.h"
@@ -564,6 +564,44 @@ static int tcl_thread_finalize(
 }
 
 /*
+** Usage: thread_swap ID ID
+**
+** Interchange the sqlite* pointer between two threads.
+*/
+static int tcl_thread_swap(
+  void *NotUsed,
+  Tcl_Interp *interp,    /* The TCL interpreter that invoked this command */
+  int argc,              /* Number of arguments */
+  const char **argv      /* Text of each argument */
+){
+  int i, j;
+  sqlite *temp;
+  if( argc!=3 ){
+    Tcl_AppendResult(interp, "wrong # args: should be \"", argv[0],
+       " ID1 ID2", 0);
+    return TCL_ERROR;
+  }
+  i = parse_thread_id(interp, argv[1]);
+  if( i<0 ) return TCL_ERROR;
+  if( !threadset[i].busy ){
+    Tcl_AppendResult(interp, "no such thread", 0);
+    return TCL_ERROR;
+  }
+  thread_wait(&threadset[i]);
+  j = parse_thread_id(interp, argv[2]);
+  if( j<0 ) return TCL_ERROR;
+  if( !threadset[j].busy ){
+    Tcl_AppendResult(interp, "no such thread", 0);
+    return TCL_ERROR;
+  }
+  thread_wait(&threadset[j]);
+  temp = threadset[i].db;
+  threadset[i].db = threadset[j].db;
+  threadset[j].db = temp;
+  return TCL_OK;
+}
+
+/*
 ** Register commands with the TCL interpreter.
 */
 int Sqlitetest4_Init(Tcl_Interp *interp){
@@ -582,6 +620,7 @@ int Sqlitetest4_Init(Tcl_Interp *interp){
      { "thread_compile",    (Tcl_CmdProc*)tcl_thread_compile    },
      { "thread_step",       (Tcl_CmdProc*)tcl_thread_step       },
      { "thread_finalize",   (Tcl_CmdProc*)tcl_thread_finalize   },
+     { "thread_swap",       (Tcl_CmdProc*)tcl_thread_swap       },
   };
   int i;