[patch] Patch to fix the ALTER memory coruption bug.

sqlite-3.2.0-alter_mem_coruption.patch (text/plain), 1.72 KB, created by Dizzy on 2005-03-27 05:22:34 UTC

--- sqlite-3.2.0.orig/src/alter.c	2005/03/19 14:45:49	1.4
+++ sqlite-3.2.0/src/alter.c	2005/03/27 01:56:31	1.5
@@ -521,7 +521,9 @@
   if( !pNew ) goto exit_begin_add_column;
   pParse->pNewTable = pNew;
   pNew->nCol = pTab->nCol;
-  nAlloc = ((pNew->nCol)/8)+8;
+  assert( pNew->nCol>0 );
+  nAlloc = (((pNew->nCol-1)/8)*8)+8;
+  assert( nAlloc>=pNew->nCol && nAlloc%8==0 && nAlloc-pNew->nCol<8 );
   pNew->aCol = (Column *)sqliteMalloc(sizeof(Column)*nAlloc);
   pNew->zName = sqliteStrDup(pTab->zName);
   if( !pNew->aCol || !pNew->zName ){
--- sqlite-3.2.0.orig/test/alter3.test	2005/03/17 12:33:14	1.3
+++ sqlite-3.2.0/test/alter3.test	2005/03/27 01:56:31	1.4
@@ -13,19 +13,19 @@
 # file format change that may be used in the future to implement
 # "ALTER TABLE ... ADD COLUMN".
 #
-# $Id: alter3.test,v 1.3 2005/03/17 12:33:14 drh Exp $
+# $Id: alter3.test,v 1.4 2005/03/27 01:56:31 danielk1977 Exp $
 #
 
 set testdir [file dirname $argv0]
 
+source $testdir/tester.tcl
+
 # If SQLITE_OMIT_ALTERTABLE is defined, omit this file.
 ifcapable !altertable {
   finish_test
   return
 }
 
-source $testdir/tester.tcl
-
 # Test Organisation:
 # ------------------
 #
@@ -336,4 +336,29 @@
   } {1}
 }
 
+# Ticket #1183 - Make sure adding columns to large tables does not cause
+# memory corruption (as was the case before this bug was fixed).
+do_test alter3-8.1 {
+  execsql {
+    CREATE TABLE t4(c1);
+  }
+} {}
+do_test alter3-8.2 {
+  set cols c1
+  for {set i 2} {$i < 100} {incr i} {
+    execsql "
+      ALTER TABLE t4 ADD c$i
+    "
+    lappend cols c$i
+  }
+  set ::sql "CREATE TABLE t4([join $cols {, }])"
+  list 
+} {}
+do_test alter3-8.2 {
+  execsql {
+    SELECT sql FROM sqlite_master WHERE name = 't4';
+  }
+} [list $::sql]
+
 finish_test
+