Change the xShmSize() implementation in os_unix.c so that it will only
increase and never decrease the size of a shared-memory segment.
FossilOrigin-Name: 149d2ae4a6fe2f86822f286d2a7092c51bec7ebb
diff --git a/manifest b/manifest
index d8efdf0..c850c8b 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,8 @@
-C Fix\sfor\sa\ssegfault\sthat\scan\sfollow\sa\smalloc\sfailure.
-D 2010-05-13T07:08:54
+-----BEGIN PGP SIGNED MESSAGE-----
+Hash: SHA1
+
+C Change\sthe\sxShmSize()\simplementation\sin\sos_unix.c\sso\sthat\sit\swill\sonly\nincrease\sand\snever\sdecrease\sthe\ssize\sof\sa\sshared-memory\ssegment.
+D 2010-05-13T08:33:36
F Makefile.arm-wince-mingw32ce-gcc fcd5e9cd67fe88836360bb4f9ef4cb7f8e2fb5a0
F Makefile.in a5cad1f8f3e021356bfcc6c77dc16f6f1952bbc3
F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
@@ -152,7 +155,7 @@
F src/os.h 8a7e2456237ecf3a2e55b02f9fe6091f1ad36902
F src/os_common.h 0d6ee583b6ee3185eb9d951f890c6dd03021a08d
F src/os_os2.c 8ad77a418630d7dee91d1bb04f79c2096301d3a0
-F src/os_unix.c c7ff5a947fc0a09de1c9c2008e3646551a1a8137
+F src/os_unix.c a65eb0c527306fbf8d5818c068cccb4179e2c187
F src/os_win.c a8fc01d8483be472e495793c01064fd87e56a5c1
F src/pager.c 1e163a82ae8405433dca559831caa06aafbba3b0
F src/pager.h 76466c3a5af56943537f68b1f16567101a0cd1d0
@@ -814,7 +817,14 @@
F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
-P 25e72f81561575051c63e9bf5d2c8e76f9fcf5c6
-R d6f93e9926f16286e5aafb3fc350bd84
-U dan
-Z c60bce3aa77615040a5ca2d947852fe0
+P 3cab9022457ce50f82c5822d8ba6c04a3a85cb6a
+R 8a7d44076bf0e05c11800be3998eddd6
+U drh
+Z 3a36caf9fe5b6632b303e603e184218b
+-----BEGIN PGP SIGNATURE-----
+Version: GnuPG v1.4.6 (GNU/Linux)
+
+iD8DBQFL67ljoxKgR168RlERAvKRAJ9jAZ2qvV6Q9GpsBE6wLhS3nq7pbACfcnYP
+hXJABDPCTP9dztwWLTfVSAc=
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diff --git a/manifest.uuid b/manifest.uuid
index 7b1e6c3..46bd746 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-3cab9022457ce50f82c5822d8ba6c04a3a85cb6a
\ No newline at end of file
+149d2ae4a6fe2f86822f286d2a7092c51bec7ebb
\ No newline at end of file
diff --git a/src/os_unix.c b/src/os_unix.c
index ff967ca..4ddff19 100644
--- a/src/os_unix.c
+++ b/src/os_unix.c
@@ -3957,16 +3957,25 @@
int rc = SQLITE_OK;
struct stat sStat;
- if( reqSize>=0 ){
+ /* On a query, this loop runs once. When reqSize>=0, the loop potentially
+ ** runs twice, except if the actual size is already greater than or equal
+ ** to the requested size, reqSize is set to -1 on the first iteration and
+ ** the loop only runs once.
+ */
+ while( 1 ){
+ if( fstat(pFile->h, &sStat)==0 ){
+ *pNewSize = (int)sStat.st_size;
+ if( reqSize>=0 && reqSize<=(int)sStat.st_size ) break;
+ }else{
+ *pNewSize = 0;
+ rc = SQLITE_IOERR;
+ break;
+ }
+ if( reqSize<0 ) break;
reqSize = (reqSize + SQLITE_UNIX_SHM_INCR - 1)/SQLITE_UNIX_SHM_INCR;
reqSize *= SQLITE_UNIX_SHM_INCR;
rc = ftruncate(pFile->h, reqSize);
- }
- if( fstat(pFile->h, &sStat)==0 ){
- *pNewSize = (int)sStat.st_size;
- }else{
- *pNewSize = 0;
- rc = SQLITE_IOERR;
+ reqSize = -1;
}
return rc;
}