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Overview
Comment:Avoid 32-bit overflow when calculating the byte offset of an overflow page in SQLITE_DIRECT_OVERFLOW_READ code. Fix for [ac0ff496b7].
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SHA1: c5256b59ad70104c1e181b9f49d1d712cf4cc9f6
User & Date: dan 2011-12-21 17:00:16
References
2011-12-21
23:38
Cherry-pick the SQLITE_DIRECT_OVERFLOW_READ fix for ticket [ac0ff496b7e] of changes [c5256b59ad] and [c723e3e18a] into the nx-devkit branch. check-in: 42f31f19 user: drh tags: nx-devkit
Context
2011-12-21
18:04
Fix other problems where 32-bit integer overflow may cause a problem. Two that require an improbably large sub-journal and two in test harness code. Ticket [ac0ff496b7e2] check-in: c723e3e1 user: dan tags: trunk
17:00
Avoid 32-bit overflow when calculating the byte offset of an overflow page in SQLITE_DIRECT_OVERFLOW_READ code. Fix for [ac0ff496b7]. check-in: c5256b59 user: dan tags: trunk
2011-12-20
13:13
Assert that the isCommit parameter to sqlite3WalFrames() is zero if and only if the nTruncate parameter is zero. check-in: 979daf92 user: drh tags: trunk
Changes
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Changes to src/btree.c.

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         && pBt->inTransaction==TRANS_READ                     /* (4) */
         && (fd = sqlite3PagerFile(pBt->pPager))->pMethods     /* (3) */
         && pBt->pPage1->aData[19]==0x01                       /* (5) */
        ){
          u8 aSave[4];
          u8 *aWrite = &pBuf[-4];
          memcpy(aSave, aWrite, 4);
          rc = sqlite3OsRead(fd, aWrite, a+4, pBt->pageSize * (nextPage-1));
          nextPage = get4byte(aWrite);
          memcpy(aWrite, aSave, 4);
        }else
#endif

        {
          DbPage *pDbPage;







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         && pBt->inTransaction==TRANS_READ                     /* (4) */
         && (fd = sqlite3PagerFile(pBt->pPager))->pMethods     /* (3) */
         && pBt->pPage1->aData[19]==0x01                       /* (5) */
        ){
          u8 aSave[4];
          u8 *aWrite = &pBuf[-4];
          memcpy(aSave, aWrite, 4);
          rc = sqlite3OsRead(fd, aWrite, a+4, (i64)pBt->pageSize*(nextPage-1));
          nextPage = get4byte(aWrite);
          memcpy(aWrite, aSave, 4);
        }else
#endif

        {
          DbPage *pDbPage;

Added test/bigfile2.test.























































































































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# 2011 December 20
#
# 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 implements regression tests for SQLite library.  The
# focus of this script testing the ability of SQLite to handle database
# files larger than 4GB.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
set testprefix bigfile2

# Create a small database.
#
do_execsql_test 1.1 {
  CREATE TABLE t1(a, b);
  INSERT INTO t1 VALUES(1, 2);
}

# Pad the file out to 4GB in size. Then clear the file-size field in the
# db header. This will cause SQLite to assume that the first 4GB of pages
# are actually in use and new pages will be appended to the file.
#
db close
if {[catch {fake_big_file 4096 [pwd]/test.db} msg]} {
  puts "**** Unable to create a file larger than 4096 MB. *****"
  finish_test
  return
}
hexio_write test.db 28 00000000

do_test 1.2 {
  file size test.db
} [expr 14 + 4096 * (1<<20)]

# Now insert a large row. The overflow pages will be located past the 4GB
# boundary. Then, after opening and closing the database, test that the row
# can be read back in. 
# 
set str [string repeat k 30000]
do_test 1.3 {
  sqlite3 db test.db
  execsql { INSERT INTO t1 VALUES(3, $str) }
  db close
  sqlite3 db test.db
  db one { SELECT b FROM t1 WHERE a = 3 }
} $str

db close
file delete test.db

finish_test