Change the OP_JournalMode implementation so that it works even if a

substitute sqlite3PagerFilename() that might return NULL is used.

FossilOrigin-Name: 491ff5fb2504173d6905e38b8ea35737338aaa84

manifest

@@ -1,5 +1,5 @@
-C Avoid\s32-bit\sinteger\soverflow\swhen\sevaluating\sthe\sexponent\sof\sa\sfloating\spoint\nvalue\sduring\sascii\sto\sbinary\sconversion.
-D 2011-10-17T20:41:46.844
+C Change\sthe\sOP_JournalMode\simplementation\sso\sthat\sit\sworks\seven\sif\sa\nsubstitute\ssqlite3PagerFilename()\sthat\smight\sreturn\sNULL\sis\sused.
+D 2011-10-17T23:15:31.767
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in a162fe39e249b8ed4a65ee947c30152786cfe897
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -238,7 +238,7 @@ F src/update.c 25e046a8f69d5e557aabde2000487b8545509d8d
 F src/utf.c 890c67dcfcc7a74623c95baac7535aadfe265e84
 F src/util.c df83983bd57057df4951516880066b42b7055269
 F src/vacuum.c 0c0ba2242355c6048d65e2b333abe0f7c06348fa
-F src/vdbe.c 75e626a6e6aefbd35b25ccab8bff533a65354638
+F src/vdbe.c 054e1d52587718605ac482e45cd93e0eae673298
 F src/vdbe.h f0725ee997db869ecae5bb70a71612aabeca7755
 F src/vdbeInt.h 693d6ac6810298fc6b4c503cfbe3f99a240f40af
 F src/vdbeapi.c 11dc47987abacb76ad016dcf5abc0dc422482a98
@@ -970,7 +970,7 @@ F tool/tostr.awk e75472c2f98dd76e06b8c9c1367f4ab07e122d06
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
 F tool/warnings-clang.sh 9f406d66e750e8ac031c63a9ef3248aaa347ef2a
 F tool/warnings.sh fbc018d67fd7395f440c28f33ef0f94420226381
-P 59bb999c8ba5e4ee7a4e388fc724b8606136d60c
-R 6b0f73ca59012aaddad5825c810302fc
+P 4becc47eb4d48686faca4f61e93e5f379b227fcc
+R 39fd2a2cf30de71b2b3450062d311602
 U drh
-Z c15000514b2d7c59bec3a3398b3cbf62
+Z 7b2456baf32ad39dc2142b8f75916654

manifest.uuid

@@ -1 +1 @@
-4becc47eb4d48686faca4f61e93e5f379b227fcc
+491ff5fb2504173d6905e38b8ea35737338aaa84

src/vdbe.c

@@ -5467,7 +5467,7 @@ case OP_JournalMode: {    /* out2-prerelease */
   ** in temporary storage or if the VFS does not support shared memory 
   */
   if( eNew==PAGER_JOURNALMODE_WAL
-   && (zFilename[0]==0                         /* Temp file */
+   && (sqlite3Strlen30(zFilename)==0           /* Temp file */
        || !sqlite3PagerWalSupported(pPager))   /* No shared-memory support */
   ){
     eNew = eOld;