Do not invoke the busy callback when trying to promote a lock from SHARED

to RESERVED.  This avoids a deadlock. (CVS 1879)

FossilOrigin-Name: d33771a303d9c20dd477b1a973024ff763203211

manifest

@@ -1,5 +1,5 @@
-C Fix\sa\sbug\sin\sthe\slogic\sthat\sconverts\snumbers\sinto\sstrings\sinside\sthe\sVM.\nTicket\s#844\s(CVS\s1878)
-D 2004-08-06T17:00:41
+C Do\snot\sinvoke\sthe\sbusy\scallback\swhen\strying\sto\spromote\sa\slock\sfrom\sSHARED\nto\sRESERVED.\s\sThis\savoids\sa\sdeadlock.\s(CVS\s1879)
+D 2004-08-07T23:54:48
 F Makefile.in 4a5e570a9e2d35b09c31b3cf01b78cea764ade4b
 F Makefile.linux-gcc a9e5a0d309fa7c38e7c14d3ecf7690879d3a5457
 F README f1de682fbbd94899d50aca13d387d1b3fd3be2dd
@@ -51,7 +51,7 @@ F src/os_unix.c d084e3443211e1556f1a33fe48580e135facbcf7
 F src/os_unix.h f3097815e041e82e24d92505e1ff61ba24172d13
 F src/os_win.c 54181eb73cb4783c4241feca9eaa490768b39008
 F src/os_win.h babd4e912967c6b09088cfe38a45e8005a07ba44
-F src/pager.c e0865a9afa64f59c6dc1cc1ab50bc700f67ee28b
+F src/pager.c 37b2159056b4c965eb055b544b301d0e7cd561dd
 F src/pager.h 67739fe649f33be55dba522ca8a9cc4e42d14f71
 F src/parse.y 589b1a39b23092888adfa9ec1f3ded8a35e8e006
 F src/pragma.c c8be18093f0492f9983406647808781ca0073d8b
@@ -60,7 +60,7 @@ F src/random.c eff68e3f257e05e81eae6c4d50a51eb88beb4ff3
 F src/select.c cbed45f4af76ad7fdfc0a0df6878b2b3827ae1d4
 F src/shell.c 4b40fac1a07512d6b8dbdf8abe0b4660d777c9ce
 F src/sqlite.h.in c340a12b4d0521efb474dd000fba3bdfb18d76da
-F src/sqliteInt.h 7a8dec83364d940372507ca4d4ff0c96bce05300
+F src/sqliteInt.h e408fb63f54c74e91ff8da1998e55b7040e57c2b
 F src/table.c 4521c278892f60e4d630788c0ea5cf4db1e75c49
 F src/tclsqlite.c cece44ee1d4427185e4ac85ddec79f31ac26965a
 F src/test1.c 9389fafc3c3a2a3b6bf4f7cffe1c7e8ccdd0be38
@@ -74,7 +74,7 @@ F src/update.c b66b1896c9da54678ba3eff2bf0b4d291a95986a
 F src/utf.c f03535db72bfa09e24202ccdd245f21d2fc65f0a
 F src/util.c 2aacc79b7bf5df5859813dafd3bf3258f67a5234
 F src/vacuum.c 9978a5760c2c430bc5b5e66505a02dad76f25813
-F src/vdbe.c f40f4ca4d9a7ba7c330e5673419f32dd3512547c
+F src/vdbe.c 6eb69df6de99f69efcb2b50a914ebbb5cad867de
 F src/vdbe.h 75b241c02431b9c0f16eaa9cdbb34146c6287f52
 F src/vdbeInt.h 3d8e08c54dcb5ca2169db8bb3a37b81a12efaecd
 F src/vdbeapi.c 3be4ccab4ba6c21d60feffc48e22cf8c1643c6d5
@@ -87,7 +87,7 @@ F test/attach2.test b175333059e86c82dbf593fc922522ecb0f8aff8
 F test/attach3.test 6d060986ff004ebb89e1876a331d96c6bb62269e
 F test/auth.test e74b015545f608c06d5b84d17acdf7146eb818af
 F test/bigfile.test 62722ac4b420dfbcdceb137b8634e2cf2865fe27
-F test/bigrow.test 8ab252dba108f12ad64e337b0f2ff31a807ac578
+F test/bigrow.test f0aeb7573dcb8caaafea76454be3ade29b7fc747
 F test/bind.test 94c3df3da774b48c6946c81b1d7f1b1646e0bd46
 F test/blob.test 8727a7b46b2073a369cfc9bcb6f54dd366b9d884
 F test/btree.test 973791eb269ab320c1a2bf0c440adee28ea936d2
@@ -130,7 +130,7 @@ F test/join4.test 8dec387d06b3a4685e1104048065cf5236b99b93
 F test/lastinsert.test 31382f88b9b0270333ac9e4a17f2c2f4732da718
 F test/laststmtchanges.test 417aa27eb2b5cdfafb46e390e2c9ddd0a20eba43
 F test/limit.test e4ee72ab4869992950f8cfce256e04a0a2a98b23
-F test/lock.test 1dbf1d06b0a7eb36237b4f107cfb3da9726b449e
+F test/lock.test 7cb9395919a0986ee4dd08bd49d34df93c8fc4fe
 F test/lock2.test 2213590d442147d09fd2334c905a755586c1c398
 F test/main.test e8c4d9ca6d1e5f5e55e6550d31aec488883b2ed9
 F test/malloc.test 769b240d89a7ef3320d88919fdb6765f9395a51f
@@ -241,7 +241,7 @@ F www/tclsqlite.tcl 06a86cba4d7fc88e2bcd633b57702d3d16abebb5
 F www/vdbe.tcl 59288db1ac5c0616296b26dce071c36cb611dfe9
 F www/version3.tcl 092a01f5ef430d2c4acc0ae558d74c4bb89638a0
 F www/whentouse.tcl a8335bce47cc2fddb07f19052cb0cb4d9129a8e4
-P ed489f776aed2de2f16e5c4b93ec6bc872118fb2
-R 1933144a8249667917769df988afd9c1
+P 863540be248d3079e1a997349be6c74199149511
+R 537860faa651d2512143eecc05e62317
 U drh
-Z 30e88cd8d59cb46c1aab06cd7ac96696
+Z a6e6f8dc54fe5cdf4e420d0a0243394b

manifest.uuid

@@ -1 +1 @@
-863540be248d3079e1a997349be6c74199149511
+d33771a303d9c20dd477b1a973024ff763203211

src/pager.c

@@ -18,7 +18,7 @@
 ** file simultaneously, or one process from reading the database while
 ** another is writing.
 **
-** @(#) $Id: pager.c,v 1.153 2004/07/22 15:02:25 drh Exp $
+** @(#) $Id: pager.c,v 1.154 2004/08/07 23:54:48 drh Exp $
 */
 #include "os.h"         /* Must be first to enable large file support */
 #include "sqliteInt.h"
@@ -2414,6 +2414,7 @@ int sqlite3pager_begin(void *pData){
       pPager->state = PAGER_EXCLUSIVE;
       pPager->origDbSize = pPager->dbSize;
     }else{
+#if 0
       int busy = 1;
       do {
         rc = sqlite3OsLock(&pPager->fd, RESERVED_LOCK);
@@ -2422,7 +2423,16 @@ int sqlite3pager_begin(void *pData){
           pPager->pBusyHandler->xFunc && 
           pPager->pBusyHandler->xFunc(pPager->pBusyHandler->pArg, busy++)
       );
+#endif
+      rc = sqlite3OsLock(&pPager->fd, RESERVED_LOCK);
       if( rc!=SQLITE_OK ){
+        /* We do not call the busy handler when we fail to get a reserved lock.
+        ** The only reason we might fail is because another process is holding
+        ** the reserved lock.  But the other process will not be able to
+        ** release its reserved lock until this process releases its shared
+        ** lock.  So we might as well fail in this process, let it release
+        ** its shared lock so that the other process can commit.
+        */
         return rc;
       }
       pPager->state = PAGER_RESERVED;

src/sqliteInt.h

@@ -11,7 +11,7 @@
 *************************************************************************
 ** Internal interface definitions for SQLite.
 **
-** @(#) $Id: sqliteInt.h,v 1.313 2004/08/04 14:29:23 drh Exp $
+** @(#) $Id: sqliteInt.h,v 1.314 2004/08/07 23:54:48 drh Exp $
 */
 #ifndef _SQLITEINT_H_
 #define _SQLITEINT_H_
@@ -173,18 +173,6 @@ struct BusyHandler {
 */
 #define Addr(X)  ((uptr)X)
 
-/*
-** The maximum number of bytes of data that can be put into a single
-** row of a single table.  The upper bound on this limit is
-** 9223372036854775808 bytes (or 2**63).  We have arbitrarily set the
-** limit to just 1MB here because the overflow page chain is inefficient
-** for really big records and we want to discourage people from thinking that 
-** multi-megabyte records are OK.  If your needs are different, you can
-** change this define and recompile to increase or decrease the record
-** size.
-*/
-#define MAX_BYTES_PER_ROW  1048576
-
 /*
 ** If memory allocation problems are found, recompile with
 **

src/vdbe.c

@@ -43,7 +43,7 @@
 ** in this file for details.  If in doubt, do not deviate from existing
 ** commenting and indentation practices when changing or adding code.
 **
-** $Id: vdbe.c,v 1.406 2004/07/24 17:38:29 drh Exp $
+** $Id: vdbe.c,v 1.407 2004/08/07 23:54:48 drh Exp $
 */
 #include "sqliteInt.h"
 #include "os.h"
@@ -2080,11 +2080,6 @@ case OP_MakeRecord: {
   nHdr += sqlite3VarintLen(nHdr);
   nByte = nHdr+nData;
 
-  if( nByte>MAX_BYTES_PER_ROW ){
-    rc = SQLITE_TOOBIG;
-    goto abort_due_to_error;
-  }
-
   /* Allocate space for the new record. */
   if( nByte>sizeof(zTemp) ){
     zNewRecord = sqliteMallocRaw(nByte);

test/bigrow.test

@@ -12,7 +12,7 @@
 # focus of this file is stressing the library by putting large amounts
 # of data in a single row of a table.
 #
-# $Id: bigrow.test,v 1.4 2001/11/24 00:31:47 drh Exp $
+# $Id: bigrow.test,v 1.5 2004/08/07 23:54:48 drh Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
@@ -205,10 +205,18 @@ for {set sz 60} {$sz<1048560} {incr sz $sz} {
   incr i
 }
 do_test bigrow-5.3 {
-  set r [catch {execsql {UPDATE t1 SET b=b||b}} msg]
-  lappend r $msg
-} {1 {too much data for one table row}}
+  catchsql {UPDATE t1 SET b=b||b}
+} {0 {}}
 do_test bigrow-5.4 {
+  execsql {SELECT length(b) FROM t1}
+} 1966080
+do_test bigrow-5.5 {
+  catchsql {UPDATE t1 SET b=b||b}
+} {0 {}}
+do_test bigrow-5.6 {
+  execsql {SELECT length(b) FROM t1}
+} 3932160
+do_test bigrow-5.99 {
   execsql {DROP TABLE t1}
 } {}
 

test/lock.test

@@ -11,7 +11,7 @@
 # This file implements regression tests for SQLite library.  The
 # focus of this script is database locks.
 #
-# $Id: lock.test,v 1.26 2004/06/19 00:16:31 drh Exp $
+# $Id: lock.test,v 1.27 2004/08/07 23:54:48 drh Exp $
 
 
 set testdir [file dirname $argv0]
@@ -170,7 +170,7 @@ do_test lock-2.2 {
 } {0 {9 8}}
 
 # If the other thread (the one that does not hold the transaction with
-# a RESERVED lock) tries to get a RESERVED lock, we get a busy callback.
+# a RESERVED lock) tries to get a RESERVED lock, we do not get a busy callback.
 #
 do_test lock-2.3 {
   proc callback {count} {
@@ -182,7 +182,7 @@ do_test lock-2.3 {
   set r [catch {execsql {UPDATE t1 SET a=b, b=a} db2} msg]
   lappend r $msg
   lappend r $::callback_value
-} {1 {database is locked} 1}
+} {1 {database is locked} {}}
 do_test lock-2.4 {
   proc callback {count} {
     lappend ::callback_value $count
@@ -193,7 +193,7 @@ do_test lock-2.4 {
   set r [catch {execsql {UPDATE t1 SET a=b, b=a} db2} msg]
   lappend r $msg
   lappend r $::callback_value
-} {1 {database is locked} {1 2 3 4 5}}
+} {1 {database is locked} {}}
 do_test lock-2.5 {
   proc callback {count} {
     lappend ::callback_value $count
@@ -205,39 +205,7 @@ do_test lock-2.5 {
   lappend r $msg
   lappend r $::callback_value
 } {0 {2 1} {}}
-
-# In this test, the 3rd invocation of the busy callback causes
-# the first thread to release its transaction.  That allows the
-# second thread to continue.
-#
-do_test lock-2.6 {
-  proc callback {count} {
-    lappend ::callback_value $count
-    if {$count>2} {
-      execsql {ROLLBACK}
-    }
-  }
-  set ::callback_value {}
-  db2 busy callback
-  set r [catch {execsql {SELECT * FROM t2} db2} msg]
-  lappend r $msg
-  lappend r $::callback_value
-} {0 {9 8} {}}
-do_test lock-2.7 {
-  proc callback {count} {
-    lappend ::callback_value $count
-    if {$count>2} {
-      execsql {ROLLBACK}
-    }
-  }
-  set ::callback_value {}
-  db2 busy callback
-  execsql {BEGIN TRANSACTION} db2
-  set r [catch {execsql {UPDATE t1 SET a = 0 WHERE 0} db2} msg]
-  execsql {ROLLBACK} db2
-  lappend r $msg
-  lappend r $::callback_value
-} {0 {} {1 2 3}}
+execsql {ROLLBACK}
 
 # Test the built-in busy timeout handler
 #
@@ -245,7 +213,7 @@ do_test lock-2.8 {
   db2 timeout 400
   execsql BEGIN
   execsql {UPDATE t1 SET a = 0 WHERE 0}
-  catchsql BEGIN db2
+  # catchsql BEGIN db2
   catchsql {UPDATE t1 SET a = 0 WHERE 0} db2
 } {1 {database is locked}}
 do_test lock-2.9 {
@@ -289,7 +257,7 @@ do_test lock-4.3 {
   db2 busy callback
   set rc [catch {db2 eval {UPDATE t1 SET a=0}} msg]
   lappend rc $msg $::callback_value
-} {1 {database is locked} {1 2 3 4 5}}
+} {1 {database is locked} {}}
 execsql {ROLLBACK}
 
 # When one thread is writing, other threads cannot read.  Except if the