Add the SQLITE_CONFIG_MUTEX symbol for use with sqlite3_config(). (CVS 5228)

FossilOrigin-Name: af1835bb5f5e3fb78d782c7c287e20db169e883f

diff --git a/manifest b/manifest
index cff7a42fe9e4d5ec7712f4e69f2b94fc0d930f85..b6ec63d3393e208c1ee1270ec39795f4a9bc22ea 100644 (file)
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Change\sthe\smutex\sinterface\sto\sbe\spluggable.\sThis\sis\san\sincremental\scheckin,\sthere\sare\sstill\schanges\sto\scome.\s(CVS\s5227)
-D 2008-06-17T17:21:18
+C Add\sthe\sSQLITE_CONFIG_MUTEX\ssymbol\sfor\suse\swith\ssqlite3_config().\s(CVS\s5228)
+D 2008-06-17T18:57:49
 F Makefile.arm-wince-mingw32ce-gcc ac5f7b2cef0cd850d6f755ba6ee4ab961b1fadf7
 F Makefile.in dc5608df93faf4406cfd7a1c8ed9ab93d8bfbfd5
 F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
@@ -115,7 +115,7 @@ F src/insert.c c2ead6c36566de8e3f130e7ab1431723a269d5d7
 F src/journal.c cffd2cd214e58c0e99c3ff632b3bee6c7cbb260e
 F src/legacy.c 3626c71fb70912abec9a4312beba753a9ce800df
 F src/loadext.c f99a75534a53e281fa2461239ee4a4b4bf6ad564
-F src/main.c 1f65b285a87f237e9e63c9628f220d10aef36b81
+F src/main.c 02f11264d00bec0a450b3570a7232eec6a4cdf5d
 F src/malloc.c 7b622d22f29e3be56d271a5a921f3b5788330189
 F src/md5.c 008216bbb5d34c6fbab5357aa68575ad8a31516a
 F src/mem1.c 159f10e280f2d9aea597cf938851e61652dd5c3d
@@ -123,7 +123,7 @@ F src/mem2.c 594270b8f0ed6c09ae5fb729eca2864139f9e293
 F src/mem3.c 617c2e2a72a10ecc5c01af14efc8c2596d2c2e87
 F src/mem4.c 45c328ec6dcb7e8d319cb383615b5fe547ca5409
 F src/mem5.c 3d2ff00c6e3bc37f5d82cd82e1a123b246fb7b39
-F src/mutex.c cbdaeeed05e3debdaf3ab4465ba32203cae44656
+F src/mutex.c d367b079d61f4b4c2925e321209da04fe226590f
 F src/mutex.h b9b9baf7050f3bb1c723e1d22088a704783a2927
 F src/mutex_os2.c b8c1231319e966875f251a7ec137bea353546b87
 F src/mutex_unix.c 74a6755912ad2a924026b54b4b5a64d327748aa5
@@ -143,7 +143,7 @@ F src/printf.c 8b063da9dcde26b7c500a01444b718d86f21bc6e
 F src/random.c 2b2db2de4ab491f5a14d3480466f8f4b5a5db74a
 F src/select.c 669687459e7d0193c89de06c5dbed55b4a41191c
 F src/shell.c a12ea645271b7876c8f080146f48e20b00d367ec
-F src/sqlite.h.in b0aacae57d08cd3909f999a0801f764287b1817f
+F src/sqlite.h.in d77f7a34f7655721cd887728874b8931a046fabb
 F src/sqlite3ext.h faacd0e6a81aabee0861c6d7883c9172e74ef5b3
 F src/sqliteInt.h f465a6d45e9cabadad5c6c097d17df3c054616d0
 F src/sqliteLimit.h f435e728c6b620ef7312814d660a81f9356eb5c8
@@ -594,7 +594,7 @@ F tool/speedtest16.c c8a9c793df96db7e4933f0852abb7a03d48f2e81
 F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
 F tool/speedtest8.c 1dbced29de5f59ba2ebf877edcadf171540374d1
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
-P 3e797d0ffe1af6f7512b3fb7b387418ac05671e0
-R e1c01b11e23adfbe56a06238817523c5
+P 597283637bcdc2398bf249b2bbc6ded47ad2de22
+R c6d0203337799c1a8192ac6a1f7c93df
 U danielk1977
-Z 7e1766078375e85380a4af4034e888e3
+Z 44fe1d3a2cecd4882d9cfff45340b7b9

diff --git a/manifest.uuid b/manifest.uuid
index e96ed556087fedf43ab674e72f57bfd990cb6022..433fcd98e97ef04104a00ed4f5868c1952f955c3 100644 (file)
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-597283637bcdc2398bf249b2bbc6ded47ad2de22
\ No newline at end of file
+af1835bb5f5e3fb78d782c7c287e20db169e883f
\ No newline at end of file

diff --git a/src/main.c b/src/main.c
index 803c0ec4bdc7b96163b5599e773525c619188e71..af2576e458c81e0be004245567722a2a3505f604 100644 (file)
--- a/src/main.c
+++ b/src/main.c
@@ -14,7 +14,7 @@
 ** other files are for internal use by SQLite and should not be
 ** accessed by users of the library.
 **
-** $Id: main.c,v 1.445 2008/06/16 20:51:16 drh Exp $
+** $Id: main.c,v 1.446 2008/06/17 18:57:49 danielk1977 Exp $
 */
 #include "sqliteInt.h"
 #include <ctype.h>
@@ -76,9 +76,7 @@ int sqlite3_initialize(void){
   if( sqlite3IsInit ) return SQLITE_OK;
   rc = sqlite3_mutex_init();
   if( rc==SQLITE_OK ){
-#ifndef SQLITE_MUTEX_NOOP
     sqlite3_mutex *pMutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);
-#endif
     sqlite3_mutex_enter(pMutex);
     if( sqlite3IsInit==0 ){
       sqlite3IsInit = 1;
@@ -153,6 +151,11 @@ int sqlite3_config(int op, ...){
       sqlite3Config.m = *va_arg(ap, sqlite3_mem_methods*);
       break;
     }
+    case SQLITE_CONFIG_MUTEX: {
+      /* Specify an alternative mutex implementation */
+      sqlite3Config.mutex = *va_arg(ap, sqlite3_mutex_methods*);
+      break;
+    }
     case SQLITE_CONFIG_MEMSTATUS: {
       /* Enable or disable the malloc status collection */
       sqlite3Config.bMemstat = va_arg(ap, int);

diff --git a/src/mutex.c b/src/mutex.c
index 3eded653bb67b0cc67b16527f4b15bbfa1f29084..46bb82d715943815de160df5b00ba8ae042c64e1 100644 (file)
--- a/src/mutex.c
+++ b/src/mutex.c
@@ -19,7 +19,7 @@
 ** implementation is suitable for testing.
 ** debugging purposes
 **
-** $Id: mutex.c,v 1.21 2008/06/17 17:21:18 danielk1977 Exp $
+** $Id: mutex.c,v 1.22 2008/06/17 18:57:49 danielk1977 Exp $
 */
 #include "sqliteInt.h"
 
@@ -30,12 +30,24 @@
 int sqlite3_mutex_init(void){ 
   int rc;
   if( !sqlite3Config.mutex.xMutexAlloc ){
+    /* If the xMutexAlloc method has not been set, then the user did not
+    ** install a mutex implementation via sqlite3_config() prior to 
+    ** sqlite3_initialize() being called. This block copies pointers to
+    ** the default implementation into the sqlite3Config structure.
+    **
+    ** The danger is that although sqlite3_config() is not a threadsafe
+    ** API, sqlite3_initialize() is, and so multiple threads may be
+    ** attempting to run this function simultaneously. To guard write
+    ** access to the sqlite3Config structure, the 'MASTER' static mutex
+    ** is obtained before modifying it.
+    */
     sqlite3_mutex_methods *p = sqlite3DefaultMutex();
     sqlite3_mutex *pMaster;
 
     rc = p->xMutexInit();
     if( rc==SQLITE_OK ){
       pMaster = p->xMutexAlloc(SQLITE_MUTEX_STATIC_MASTER);
+      assert(pMaster);
       p->xMutexEnter(pMaster);
       assert( sqlite3Config.mutex.xMutexAlloc==0 
            || sqlite3Config.mutex.xMutexAlloc==p->xMutexAlloc
@@ -45,7 +57,6 @@ int sqlite3_mutex_init(void){
       }
       p->xMutexLeave(pMaster);
     }
-
   }else{
     rc = sqlite3Config.mutex.xMutexInit();
   }

diff --git a/src/sqlite.h.in b/src/sqlite.h.in
index 592b1e17490976c3c250f437e0b8a6b07e7c47ab..d9b8921aa18f8fffe881496ba87cc1761ca46443 100644 (file)
--- a/src/sqlite.h.in
+++ b/src/sqlite.h.in
@@ -30,7 +30,7 @@
 ** the version number) and changes its name to "sqlite3.h" as
 ** part of the build process.
 **
-** @(#) $Id: sqlite.h.in,v 1.330 2008/06/17 17:21:18 danielk1977 Exp $
+** @(#) $Id: sqlite.h.in,v 1.331 2008/06/17 18:57:49 danielk1977 Exp $
 */
 #ifndef _SQLITE3_H_
 #define _SQLITE3_H_
@@ -1050,6 +1050,7 @@ struct sqlite3_mem_methods {
 #define SQLITE_CONFIG_SERIALIZED    3  /* nil */
 #define SQLITE_CONFIG_MALLOC        4  /* sqlite3_mem_methods* */
 #define SQLITE_CONFIG_MEMSTATUS     5  /* boolean */
+#define SQLITE_CONFIG_MUTEX         6  /* sqlite3_mutex_methods* */
 
 /* These options are to be added later.  Currently unused and undocumented. */
 #define SQLITE_CONFIG_HEAP          6  /* void*, int64, min, max, tmp */