SQLite

Check-in [e75b52d156]
Login

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

Overview
Comment:In shared-cache mode, do not allow one connection to checkpoint a database while a second connection is reading or writing the same shared-cache.
Downloads: Tarball | ZIP archive
Timelines: family | ancestors | descendants | both | trunk
Files: files | file ages | folders
SHA1: e75b52d156905ce16bedb94f65c01a4640bdfa75
User & Date: dan 2010-08-02 10:47:06.000
Context
2010-08-02
10:59
Modify wal2.test to disable tests requiring TCL 8.5 if the test harness is compiled using TCL 8.4. (check-in: 016486c7d5 user: drh tags: trunk)
10:47
In shared-cache mode, do not allow one connection to checkpoint a database while a second connection is reading or writing the same shared-cache. (check-in: e75b52d156 user: dan tags: trunk)
2010-08-01
22:41
Fix a typo in an error message of the TCL interface. (check-in: 8eadd7b87b user: drh tags: trunk)
Changes
Unified Diff Ignore Whitespace Patch
Changes to src/btree.c.
︙︙
7843
7844
7845
7846
7847
7848
7849























7850
7851
7852
7853
7854
7855
7856

/*
** Return non-zero if a transaction is active.
*/
int sqlite3BtreeIsInTrans(Btree *p){
  assert( p==0 || sqlite3_mutex_held(p->db->mutex) );
  return (p && (p->inTrans==TRANS_WRITE));
}
























/*
** Return non-zero if a read (or write) transaction is active.
*/
int sqlite3BtreeIsInReadTrans(Btree *p){
  assert( p );
  assert( sqlite3_mutex_held(p->db->mutex) );








>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>








7843
7844
7845
7846
7847
7848
7849
7850
7851
7852
7853
7854
7855
7856
7857
7858
7859
7860
7861
7862
7863
7864
7865
7866
7867
7868
7869
7870
7871
7872
7873
7874
7875
7876
7877
7878
7879

/*
** Return non-zero if a transaction is active.
*/
int sqlite3BtreeIsInTrans(Btree *p){
  assert( p==0 || sqlite3_mutex_held(p->db->mutex) );
  return (p && (p->inTrans==TRANS_WRITE));
}

#ifndef SQLITE_OMIT_WAL
/*
** Run a checkpoint on the Btree passed as the first argument.
**
** Return SQLITE_LOCKED if this or any other connection has an open 
** transaction on the shared-cache the argument Btree is connected to.
*/
int sqlite3BtreeCheckpoint(Btree *p){
  int rc = SQLITE_OK;
  if( p ){
    BtShared *pBt = p->pBt;
    sqlite3BtreeEnter(p);
    if( pBt->inTransaction!=TRANS_NONE ){
      rc = SQLITE_LOCKED;
    }else{
      rc = sqlite3PagerCheckpoint(pBt->pPager);
    }
    sqlite3BtreeLeave(p);
  }
  return rc;
}
#endif

/*
** Return non-zero if a read (or write) transaction is active.
*/
int sqlite3BtreeIsInReadTrans(Btree *p){
  assert( p );
  assert( sqlite3_mutex_held(p->db->mutex) );
︙︙
Changes to src/btree.h.
︙︙
196
197
198
199
200
201
202




203
204
205
206
207
208
209

int sqlite3BtreeCount(BtCursor *, i64 *);
#endif

#ifdef SQLITE_TEST
int sqlite3BtreeCursorInfo(BtCursor*, int*, int);
void sqlite3BtreeCursorList(Btree*);
#endif





/*
** If we are not using shared cache, then there is no need to
** use mutexes to access the BtShared structures.  So make the
** Enter and Leave procedures no-ops.
*/
#ifndef SQLITE_OMIT_SHARED_CACHE








>
>
>
>








196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213

int sqlite3BtreeCount(BtCursor *, i64 *);
#endif

#ifdef SQLITE_TEST
int sqlite3BtreeCursorInfo(BtCursor*, int*, int);
void sqlite3BtreeCursorList(Btree*);
#endif

#ifndef SQLITE_OMIT_WAL
  int sqlite3BtreeCheckpoint(Btree*);
#endif

/*
** If we are not using shared cache, then there is no need to
** use mutexes to access the BtShared structures.  So make the
** Enter and Leave procedures no-ops.
*/
#ifndef SQLITE_OMIT_SHARED_CACHE
︙︙
Changes to src/main.c.
︙︙
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327

  int rc = SQLITE_OK;             /* Return code */
  int i;                          /* Used to iterate through attached dbs */

  assert( sqlite3_mutex_held(db->mutex) );

  for(i=0; i<db->nDb && rc==SQLITE_OK; i++){
    if( i==iDb || iDb==SQLITE_MAX_ATTACHED ){
      Btree *pBt = db->aDb[i].pBt;
      if( pBt ){
        if( sqlite3BtreeIsInReadTrans(pBt) ){
          rc = SQLITE_LOCKED;
        }else{
          sqlite3BtreeEnter(pBt);
          rc = sqlite3PagerCheckpoint(sqlite3BtreePager(pBt));
          sqlite3BtreeLeave(pBt);
        }
      }
    }
  }

  return rc;
}
#endif /* SQLITE_OMIT_WAL */









|
<
<
<
<
<
<
<
<
<








1304
1305
1306
1307
1308
1309
1310
1311









1312
1313
1314
1315
1316
1317
1318

  int rc = SQLITE_OK;             /* Return code */
  int i;                          /* Used to iterate through attached dbs */

  assert( sqlite3_mutex_held(db->mutex) );

  for(i=0; i<db->nDb && rc==SQLITE_OK; i++){
    if( i==iDb || iDb==SQLITE_MAX_ATTACHED ){
      rc = sqlite3BtreeCheckpoint(db->aDb[i].pBt);









    }
  }

  return rc;
}
#endif /* SQLITE_OMIT_WAL */
︙︙
Added test/walshared.test. 


























































































































>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>
>

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60

# 2010 August 2
#
# 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 file is testing the operation of the library in
# "PRAGMA journal_mode=WAL" mode with shared-cache turned on.
#

set testdir [file dirname $argv0]
source $testdir/tester.tcl
db close
set ::enable_shared_cache [sqlite3_enable_shared_cache 1]

sqlite3 db  test.db
sqlite3 db2 test.db

do_test walshared-1.0 {
  execsql {
    PRAGMA cache_size = 10;
    PRAGMA journal_mode = WAL;
    CREATE TABLE t1(a PRIMARY KEY, b UNIQUE);
    INSERT INTO t1 VALUES(randomblob(100), randomblob(200));
  }
} {wal}

do_test walshared-1.1 {
  execsql {
    BEGIN;
      INSERT INTO t1 VALUES(randomblob(100), randomblob(200));
      INSERT INTO t1 SELECT randomblob(100), randomblob(200) FROM t1;
      INSERT INTO t1 SELECT randomblob(100), randomblob(200) FROM t1;
      INSERT INTO t1 SELECT randomblob(100), randomblob(200) FROM t1;
  }
} {}

do_test walshared-1.2 {
  catchsql { PRAGMA wal_checkpoint }
} {1 {database table is locked}}

do_test walshared-1.3 {
  catchsql { PRAGMA wal_checkpoint } db2
} {1 {database table is locked}}

do_test walshared-1.4 {
  execsql { COMMIT }
  execsql { PRAGMA integrity_check } db2
} {ok}



sqlite3_enable_shared_cache $::enable_shared_cache
finish_test