Allow xDestroy methods to execute "DROP TABLE" statements. (CVS 3287)

FossilOrigin-Name: a56bfa560425a5dc9273229f8838471dfc402024

manifest

@@ -1,5 +1,5 @@
-C Fix\ssome\smemory\sleaks\sthat\soccur\swhen\smalloc()\sfails.\s(CVS\s3286)
-D 2006-06-23T11:34:55
+C Allow\sxDestroy\smethods\sto\sexecute\s"DROP\sTABLE"\sstatements.\s(CVS\s3287)
+D 2006-06-23T14:32:08
 F Makefile.in f839b470345d3cb4b0644068474623fe2464b5d3
 F Makefile.linux-gcc 2d8574d1ba75f129aba2019f0b959db380a90935
 F README 9c4e2d6706bdcc3efdd773ce752a8cdab4f90028
@@ -84,7 +84,7 @@ F src/test4.c 8b784cd82de158a2317cb4ac4bc86f91ad315e25
 F src/test5.c 7162f8526affb771c4ed256826eee7bb9eca265f
 F src/test6.c 60a02961ceb7b3edc25f5dc5c1ac2556622a76de
 F src/test7.c 03fa8d787f6aebc6d1f72504d52f33013ad2c8e3
-F src/test8.c 9ea0fd1708d714205b2db044d9d1e081182602a1
+F src/test8.c 054989bf4b6f10ffac090e24ce6843662ebb9b91
 F src/test_async.c e3deaedd4d86a56391b81808fde9e44fbd92f1d3
 F src/test_loadext.c 22065d601a18878e5542191001f0eaa5d77c0ed8
 F src/test_md5.c 6c42bc0a3c0b54be34623ff77a0eec32b2fa96e3
@@ -97,9 +97,9 @@ F src/update.c 686b13db8b28a129a2407aaffc8b7588d1104e0b
 F src/utf.c ab81ac59084ff1c07d421eb1a0a84ec809603b44
 F src/util.c ca6ee72772c0f5dc04d2e0ab1973fd3b6a9bf79d
 F src/vacuum.c 5b37d0f436f8e1ffacd17934e44720b38d2247f9
-F src/vdbe.c 1e16fbc5ba4d84f2310ebac4cc61e387ab4da130
+F src/vdbe.c 294e2f35fbd81f5b1e4bd918d2d0bb38313d4b11
 F src/vdbe.h 258b5d1c0aaa72192f09ff0568ce42b383f156fa
-F src/vdbeInt.h de89a3475a0a914c49f92e51c303f7dd6f2b21fe
+F src/vdbeInt.h be3396aa33e7587c96f8c8c264100623a071a3d0
 F src/vdbeapi.c 6af0e7160af260052a7a4500464221a03dada75f
 F src/vdbeaux.c 1144cee0a5644c26f63e7fa34574dcd9349ac799
 F src/vdbefifo.c 9efb94c8c3f4c979ebd0028219483f88e57584f5
@@ -291,7 +291,7 @@ F test/vacuum.test 37f998b841cb335397c26d9bbc3457182af2565f
 F test/vacuum2.test 5aea8c88a65cb29f7d175296e7c819c6158d838c
 F test/varint.test ab7b110089a08b9926ed7390e7e97bdefeb74102
 F test/view.test 16e2774fe35e47a07ac4471b7f0bcc948b1aa6d5
-F test/vtab1.test 3f21d81e599afd100e60830f5f0426c1f74febda
+F test/vtab1.test 55c7415e8b6c05a648c57434b97dcd709bec4e53
 F test/vtab2.test e57f9865368df26ef5eb8bc630962d82086f174b
 F test/vtab3.test f38d6d7d19f08bffdadce4d5b8cba078f8118587
 F test/vtab4.test 4b4293341443839ef6dc02f8d9e614702a6c67ff
@@ -373,7 +373,7 @@ F www/tclsqlite.tcl bb0d1357328a42b1993d78573e587c6dcbc964b9
 F www/vdbe.tcl 87a31ace769f20d3627a64fa1fade7fed47b90d0
 F www/version3.tcl 890248cf7b70e60c383b0e84d77d5132b3ead42b
 F www/whentouse.tcl 97e2b5cd296f7d8057e11f44427dea8a4c2db513
-P 5d1d907189ff3ca7afada83033280cf258984ac0
-R 9aaa96fd253428f51eb81ad079eb4637
+P b56cc035f2be5c1a3f63efbb4c181e405a140fbb
+R d196b750d3fe8f695cd7b6908a213779
 U danielk1977
-Z 5fb128a15d49c4268bc0417c4ae9ed76
+Z 3dbe3cb63d42318e08050a7c6163ebb3

manifest.uuid

@@ -1 +1 @@
-b56cc035f2be5c1a3f63efbb4c181e405a140fbb
+a56bfa560425a5dc9273229f8838471dfc402024

src/test8.c

@@ -13,7 +13,7 @@
 ** is not included in the SQLite library.  It is used for automated
 ** testing of the SQLite library.
 **
-** $Id: test8.c,v 1.33 2006/06/23 11:34:55 danielk1977 Exp $
+** $Id: test8.c,v 1.34 2006/06/23 14:32:08 danielk1977 Exp $
 */
 #include "sqliteInt.h"
 #include "tcl.h"
@@ -238,6 +238,7 @@ static int echoDestructor(sqlite3_vtab *pVtab){
   }
   sqliteFree(p->aCol);
   sqliteFree(p->zTableName);
+  sqliteFree(p->zLogName);
   sqliteFree(p);
   return 0;
 }
@@ -286,7 +287,7 @@ static int echoCreate(
   int rc = SQLITE_OK;
   appendToEchoModule((Tcl_Interp *)(pAux), "xCreate");
   rc = echoConstructor(db, pAux, argc, argv, ppVtab);
-#if 0
+#if 1
   if( rc==SQLITE_OK && argc==5 ){
     char *zSql;
     echo_vtab *pVtab = *(echo_vtab **)ppVtab;
@@ -316,7 +317,7 @@ static int echoDestroy(sqlite3_vtab *pVtab){
   int rc = SQLITE_OK;
   echo_vtab *p = (echo_vtab *)pVtab;
   appendToEchoModule(((echo_vtab *)pVtab)->interp, "xDestroy");
-#if 0
+#if 1
   if( p && p->zLogName ){
     char *zSql;
     zSql = sqlite3MPrintf("DROP TABLE %Q", p->zLogName);

src/vdbe.c

@@ -43,7 +43,7 @@
 ** in this file for details.  If in doubt, do not deviate from existing
 ** commenting and indentation practices when changing or adding code.
 **
-** $Id: vdbe.c,v 1.567 2006/06/23 11:34:55 danielk1977 Exp $
+** $Id: vdbe.c,v 1.568 2006/06/23 14:32:08 danielk1977 Exp $
 */
 #include "sqliteInt.h"
 #include "os.h"
@@ -3894,10 +3894,20 @@ case OP_IdxIsNull: {        /* no-push */
 */
 case OP_Destroy: {
   int iMoved;
-  if( db->activeVdbeCnt>1 ){
+  Vdbe *pVdbe;
+  int iCnt = db->activeVdbeCnt;
+#ifndef SQLITE_OMIT_VIRTUALTABLE
+  iCnt = 0;
+  for(pVdbe=db->pVdbe; pVdbe; pVdbe=pVdbe->pNext){
+    if( pVdbe->magic==VDBE_MAGIC_RUN && pVdbe->inVtabMethod<2 && pVdbe->pc>=0 ){
+      iCnt++;
+    }
+  }
+#endif
+  if( iCnt>1 ){
     rc = SQLITE_LOCKED;
   }else{
-    assert( db->activeVdbeCnt==1 );
+    assert( iCnt==1 );
     rc = sqlite3BtreeDropTable(db->aDb[pOp->p2].pBt, pOp->p1, &iMoved);
     pTos++;
     pTos->flags = MEM_Int;
@@ -4568,7 +4578,9 @@ case OP_VCreate: {   /* no-push */
 ** of that table.
 */
 case OP_VDestroy: {   /* no-push */
+  p->inVtabMethod = 2;
   rc = sqlite3VtabCallDestroy(db, pOp->p1, pOp->p3);
+  p->inVtabMethod = 0;
   break;
 }
 #endif /* SQLITE_OMIT_VIRTUALTABLE */

src/vdbeInt.h

@@ -272,6 +272,14 @@ struct Context {
 **
 ** The "sqlite3_stmt" structure pointer that is returned by sqlite3_compile()
 ** is really a pointer to an instance of this structure.
+**
+** The Vdbe.inVtabMethod variable is set to non-zero for the duration of
+** any virtual table method invocations made by the vdbe program. It is
+** set to 2 for xDestroy method calls and 1 for all other methods. This
+** variable is used for two purposes: to allow xDestroy methods to execute
+** "DROP TABLE" statements and to prevent some nasty side effects of
+** malloc failure when SQLite is invoked recursively by a virtual table 
+** method function.
 */
 struct Vdbe {
   sqlite3 *db;        /* The whole database */
@@ -326,7 +334,7 @@ struct Vdbe {
   int lru;              /* Counter used for LRU cache replacement */
 #endif
 #ifndef SQLITE_OMIT_VIRTUALTABLE
-  int inVtabMethod;
+  int inVtabMethod;     /* See comments above */
 #endif
 };
 

test/vtab1.test

@@ -11,7 +11,7 @@
 # This file implements regression tests for SQLite library.  The
 # focus of this file is creating and dropping virtual tables.
 #
-# $Id: vtab1.test,v 1.29 2006/06/22 09:53:50 danielk1977 Exp $
+# $Id: vtab1.test,v 1.30 2006/06/23 14:32:09 danielk1977 Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
@@ -748,26 +748,20 @@ do_test vtab1.8-2 {
   }
 } {}
 
-if 0 {
-  do_test vtab1.9-1 {
-    set echo_module ""
-    execsql {
-      CREATE TABLE r(a, b, c);
-      CREATE VIRTUAL TABLE e USING echo(r, e_log);
-      SELECT name FROM sqlite_master;
-    }
-  } {r e e_log}
-  do_test vtab1.9-2 {
-    explain {
-      DROP TABLE e;
-    }
-    execsql {
-      PRAGMA vdbe_trace = 1;
-      DROP TABLE e;
-      SELECT name FROM sqlite_master;
-    }
-  } {r}
-}
+do_test vtab1.9-1 {
+  set echo_module ""
+  execsql {
+    CREATE TABLE r(a, b, c);
+    CREATE VIRTUAL TABLE e USING echo(r, e_log);
+    SELECT name FROM sqlite_master;
+  }
+} {r e e_log}
+do_test vtab1.9-2 {
+  execsql {
+    DROP TABLE e;
+    SELECT name FROM sqlite_master;
+  }
+} {r}
 
 finish_test