SQLite

Check-in [859792958b]
Login

Many hyperlinks are disabled.
Use anonymous login to enable hyperlinks.

Overview
Comment:Remove an unreachable branch from lockBtree(). Add comments. (CVS 6428)
Downloads: Tarball | ZIP archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1: 859792958b4d4a3623d68526ff773f778bdf3f0d
User & Date: danielk1977 2009-04-01 19:07:04.000
Context
2009-04-01
19:35
Change an unreachable error condition test to an assert() in rowset.c. (CVS 6429) (check-in: 36115e4073 user: drh tags: trunk)
19:07
Remove an unreachable branch from lockBtree(). Add comments. (CVS 6428) (check-in: 859792958b user: danielk1977 tags: trunk)
18:40
Fix a bug in the sqlite3Utf16ByteLen() function so that it computes the correct length even for strings that contain surrogate pairs. Ticket #3766. (CVS 6427) (check-in: 766bb7e59c user: drh tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to src/btree.c.
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
/*
** 2004 April 6
**
** 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.
**
*************************************************************************
** $Id: btree.c,v 1.586 2009/04/01 18:03:01 danielk1977 Exp $
**
** This file implements a external (disk-based) database using BTrees.
** See the header comment on "btreeInt.h" for additional information.
** Including a description of file format and an overview of operation.
*/
#include "btreeInt.h"












|







1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
/*
** 2004 April 6
**
** 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.
**
*************************************************************************
** $Id: btree.c,v 1.587 2009/04/01 19:07:04 danielk1977 Exp $
**
** This file implements a external (disk-based) database using BTrees.
** See the header comment on "btreeInt.h" for additional information.
** Including a description of file format and an overview of operation.
*/
#include "btreeInt.h"

1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
*/
static int lockBtree(BtShared *pBt){
  int rc;
  MemPage *pPage1;
  int nPage;

  assert( sqlite3_mutex_held(pBt->mutex) );
  if( pBt->pPage1 ) return SQLITE_OK;
  rc = sqlite3BtreeGetPage(pBt, 1, &pPage1, 0);
  if( rc!=SQLITE_OK ) return rc;

  /* Do some checking to help insure the file we opened really is
  ** a valid database file. 
  */
  rc = sqlite3PagerPagecount(pBt->pPager, &nPage);







|







1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
*/
static int lockBtree(BtShared *pBt){
  int rc;
  MemPage *pPage1;
  int nPage;

  assert( sqlite3_mutex_held(pBt->mutex) );
  assert( pBt->pPage1==0 );
  rc = sqlite3BtreeGetPage(pBt, 1, &pPage1, 0);
  if( rc!=SQLITE_OK ) return rc;

  /* Do some checking to help insure the file we opened really is
  ** a valid database file. 
  */
  rc = sqlite3PagerPagecount(pBt->pPager, &nPage);
2151
2152
2153
2154
2155
2156
2157
2158
2159


2160


2161
2162
2163
2164
2165
2166
2167
2168
2169
    sqlite3ConnectionBlocked(p->db, pBlock);
    rc = SQLITE_LOCKED_SHAREDCACHE;
    goto trans_begun;
  }
#endif

  do {
    if( pBt->pPage1==0 ){
      do{


        rc = lockBtree(pBt);


      }while( pBt->pPage1==0 && rc==SQLITE_OK );
    }

    if( rc==SQLITE_OK && wrflag ){
      if( pBt->readOnly ){
        rc = SQLITE_READONLY;
      }else{
        rc = sqlite3PagerBegin(pBt->pPager, wrflag>1);
        if( rc==SQLITE_OK ){







|
|
>
>
|
>
>
|
<







2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165

2166
2167
2168
2169
2170
2171
2172
    sqlite3ConnectionBlocked(p->db, pBlock);
    rc = SQLITE_LOCKED_SHAREDCACHE;
    goto trans_begun;
  }
#endif

  do {
    /* Call lockBtree() until either pBt->pPage1 is populated or
    ** lockBtree() returns something other than SQLITE_OK. lockBtree()
    ** may return SQLITE_OK but leave pBt->pPage1 set to 0 if after
    ** reading page 1 it discovers that the page-size of the database 
    ** file is not pBt->pageSize. In this case lockBtree() will update
    ** pBt->pageSize to the page-size of the file on disk.
    */
    while( pBt->pPage1==0 && SQLITE_OK==(rc = lockBtree(pBt)) );


    if( rc==SQLITE_OK && wrflag ){
      if( pBt->readOnly ){
        rc = SQLITE_READONLY;
      }else{
        rc = sqlite3PagerBegin(pBt->pPager, wrflag>1);
        if( rc==SQLITE_OK ){