From 1fab7b6664b9e90b477213681a8d0428fc03f806 Mon Sep 17 00:00:00 2001
From: danielk1977 <danielk1977@noemail.net>
Date: Wed, 7 Jan 2009 10:35:18 +0000
Subject: [PATCH] Fix a problem with reverting a 'DROP TABLE' command executed
 inside of a savepoint on an auto-vacuum database. (CVS 6129)

FossilOrigin-Name: 3a4bb83235e9a79297e7d5d47ac7674c9df960bf
---
 manifest            | 14 +++++++-------
 manifest.uuid       |  2 +-
 src/pager.c         | 25 +++++++++++++++++++++++--
 test/savepoint.test | 33 +++++++++++++++++++++++++++++++--
 4 files changed, 62 insertions(+), 12 deletions(-)

diff --git a/manifest b/manifest
index b19adb7a1c..fc7c841213 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Fix\ssavepoint\srelated\sbugs.\sA\srollback\scaused\sby\san\sIO\serror\sor\s"OR\sROLLBACK"\sclause\swhile\sone\sor\smore\ssavepoints\swere\sopen\swas\sleaving\sthe\ssqlite3\sstructure\sin\san\sinvalid\sstate.\s(CVS\s6128)
-D 2009-01-07T08:12:16
+C Fix\sa\sproblem\swith\sreverting\sa\s'DROP\sTABLE'\scommand\sexecuted\sinside\sof\sa\ssavepoint\son\san\sauto-vacuum\sdatabase.\s(CVS\s6129)
+D 2009-01-07T10:35:19
 F Makefile.arm-wince-mingw32ce-gcc fcd5e9cd67fe88836360bb4f9ef4cb7f8e2fb5a0
 F Makefile.in 05461a9b5803d5ad10c79f989801e9fd2cc3e592
 F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
@@ -142,7 +142,7 @@ F src/os_common.h 24525d8b7bce66c374dfc1810a6c9043f3359b60
 F src/os_os2.c bed77dc26e3a95ce4a204936b9a1ca6fe612fcc5
 F src/os_unix.c e6eacc7ec735ded605fefcbaf250058baa8feb12
 F src/os_win.c 496e3ceb499aedc63622a89ef76f7af2dd902709
-F src/pager.c b2a42a1d06813daf423848d8245da00fc8de44d3
+F src/pager.c 59a70fae1d6594734c652ad33c97afd9ebc29268
 F src/pager.h 0793c5e4faed6c278037eb22b2434b318687d615
 F src/parse.y 4d0e33a702dc3ea7b69d8ae1914b3fbd32e46057
 F src/pcache.c 16dc8da6e6ba6250f8dfd9ee46036db1cbceedc6
@@ -493,7 +493,7 @@ F test/rollback.test 1f70ab4301d8d105d41438a436cad1fc8897f5e5
 F test/rowid.test 1c8fc43c60d273e6ea44dfb992db587f3164312c
 F test/rtree.test b85fd4f0861a40ca366ac195e363be2528dcfadf
 F test/safety.test b69e2b2dd5d52a3f78e216967086884bbc1a09c6
-F test/savepoint.test b5ce04cc17d93b73065fec81eb795c131f168b42
+F test/savepoint.test 2ffa8b0526b5b4a857abc9cc57fe4d7d0474ded0
 F test/savepoint2.test 18f6c75d5c133b93838019df8988b8cdf379d3de
 F test/savepoint3.test 0c6c6cf208a2865301d125bf962b8f8a12f58b70
 F test/savepoint4.test fd8850063e3c40565545f5c291e7f79a30591670
@@ -692,7 +692,7 @@ F tool/speedtest16.c c8a9c793df96db7e4933f0852abb7a03d48f2e81
 F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
 F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
-P e426860b94f5b47e3a265549dbac64a421cae425
-R eefa8be568f0cc6f54700fdfc1171597
+P e5d42c69a3b325ca12f53184e33964230acbdd1f
+R a5a8625aaf9e409d433ca7b188e79539
 U danielk1977
-Z 6c956af5da49349b5b9902fd748769e9
+Z de63ae952f3922615c231e9860293c66
diff --git a/manifest.uuid b/manifest.uuid
index 15c7bd91ae..a2524046cb 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-e5d42c69a3b325ca12f53184e33964230acbdd1f
\ No newline at end of file
+3a4bb83235e9a79297e7d5d47ac7674c9df960bf
\ No newline at end of file
diff --git a/src/pager.c b/src/pager.c
index f7b5055ed7..14776d4406 100644
--- a/src/pager.c
+++ b/src/pager.c
@@ -18,7 +18,7 @@
 ** file simultaneously, or one process from reading the database while
 ** another is writing.
 **
-** @(#) $Id: pager.c,v 1.535 2009/01/07 02:03:35 drh Exp $
+** @(#) $Id: pager.c,v 1.536 2009/01/07 10:35:19 danielk1977 Exp $
 */
 #ifndef SQLITE_OMIT_DISKIO
 #include "sqliteInt.h"
@@ -4303,9 +4303,31 @@ void sqlite3PagerSetCodec(
 int sqlite3PagerMovepage(Pager *pPager, DbPage *pPg, Pgno pgno, int isCommit){
   PgHdr *pPgOld;  /* The page being overwritten. */
   Pgno needSyncPgno = 0;
+  int rc;
 
   assert( pPg->nRef>0 );
 
+  /* If the page being moved is dirty and has not been saved by the latest
+  ** savepoint, then save the current contents of the page into the 
+  ** sub-journal now. This is required to handle the following scenario:
+  **
+  **   BEGIN;
+  **     <journal page X, then modify it in memory>
+  **     SAVEPOINT one;
+  **       <Move page X to location Y>
+  **     ROLLBACK TO one;
+  **
+  ** If page X were not written to the sub-journal here, it would not
+  ** be possible to restore its contents when the "ROLLBACK TO one"
+  ** statement were processed.
+  */
+  if( pPg->flags&PGHDR_DIRTY 
+   && subjRequiresPage(pPg)
+   && SQLITE_OK!=(rc = subjournalPage(pPg))
+  ){
+    return rc;
+  }
+
   PAGERTRACE(("MOVE %d page %d (needSync=%d) moves to %d\n", 
       PAGERID(pPager), pPg->pgno, (pPg->flags&PGHDR_NEED_SYNC)?1:0, pgno));
   IOTRACE(("MOVE %p %d %d\n", pPager, pPg->pgno, pgno))
@@ -4365,7 +4387,6 @@ int sqlite3PagerMovepage(Pager *pPager, DbPage *pPg, Pgno pgno, int isCommit){
     ** The sqlite3PagerGet() call may cause the journal to sync. So make
     ** sure the Pager.needSync flag is set too.
     */
-    int rc;
     PgHdr *pPgHdr;
     assert( pPager->needSync );
     rc = sqlite3PagerGet(pPager, needSyncPgno, &pPgHdr);
diff --git a/test/savepoint.test b/test/savepoint.test
index df1a15f5f5..4d21e81d19 100644
--- a/test/savepoint.test
+++ b/test/savepoint.test
@@ -9,7 +9,7 @@
 #
 #***********************************************************************
 #
-# $Id: savepoint.test,v 1.9 2009/01/07 08:12:16 danielk1977 Exp $
+# $Id: savepoint.test,v 1.10 2009/01/07 10:35:19 danielk1977 Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
@@ -740,11 +740,40 @@ do_test savepoint-11.6 {
   }
 } {}
 integrity_check savepoint-11.7
-do_test savepoint-11.6 {
+do_test savepoint-11.8 {
   execsql { ROLLBACK }
   file size test.db
 } {8192}
 
+
+do_test savepoint-11.9 {
+  execsql {
+    DROP TABLE IF EXISTS t1;
+    DROP TABLE IF EXISTS t2;
+    DROP TABLE IF EXISTS t3;
+  }
+} {}
+do_test savepoint-11.10 {
+  execsql {
+    BEGIN;
+      CREATE TABLE t1(a, b);
+      CREATE TABLE t2(x, y);
+      INSERT INTO t2 VALUES(1, 2);
+      SAVEPOINT one;
+        INSERT INTO t2 VALUES(3, 4);
+        SAVEPOINT two;
+          DROP TABLE t1;
+        ROLLBACK TO two;
+  }
+  execsql {SELECT * FROM t2}
+} {1 2 3 4}
+do_test savepoint-11.11 {
+  execsql COMMIT
+} {}
+do_test savepoint-11.12 {
+  execsql {SELECT * FROM t2}
+} {1 2 3 4}
+
 #-------------------------------------------------------------------------
 # The following tests - savepoint-12.* - test the interaction of 
 # savepoints and "ON CONFLICT ROLLBACK" clauses.