From: drh <drh@noemail.net>
Date: Fri, 28 Jan 2011 15:46:14 +0000 (+0000)
Subject: Change pager_truncate() to a different method for extending files while
X-Git-Tag: version-3.7.5~2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=bd1334dfd9311683b489e29427d67f5497a363bf;p=thirdparty%2Fsqlite.git

Change pager_truncate() to a different method for extending files while
also ensuring that writes are page-size and page-aligned.

FossilOrigin-Name: 874bc8844f6494cdbf700bd884dee67d40f11fc0
---

diff --git a/manifest b/manifest
index 1a0fcdfffb..546ad98ff0 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,8 @@
-C When\sextending\sa\sdatabase\sfile,\sdo\sso\sby\swriting\sone\sor\smore\spage-size\schunks\sof\sdata\sto\sthe\sfile,\sinstead\sof\sjust\sa\ssingle\sbyte\sto\sthe\send.
-D 2011-01-28T15:07:56
+-----BEGIN PGP SIGNED MESSAGE-----
+Hash: SHA1
+
+C Change\spager_truncate()\sto\sa\sdifferent\smethod\sfor\sextending\sfiles\swhile\nalso\sensuring\sthat\swrites\sare\spage-size\sand\spage-aligned.
+D 2011-01-28T15:46:14.305
 F Makefile.arm-wince-mingw32ce-gcc d6df77f1f48d690bd73162294bbba7f59507c72f
 F Makefile.in de6498556d536ae60bb8bb10e8c1ba011448658c
 F Makefile.linux-gcc 91d710bdc4998cb015f39edf3cb314ec4f4d7e23
@@ -162,7 +165,7 @@ F src/os_common.h a8f95b81eca8a1ab8593d23e94f8a35f35d4078f
 F src/os_os2.c 2e452c9f2ca507623ad351c33a8a8b27849b1863
 F src/os_unix.c 1be46a35bad4bec5171e4de88aaff817260eb378
 F src/os_win.c 9abdcdd925416d854eabb0996c96debd92abfef5
-F src/pager.c 3327c903932466adead8b4f4e9c6e5f958cae2a9
+F src/pager.c b0fcbe3038fd08b111e1cf1deddd5f42418004d8
 F src/pager.h 0ea59db2a33bc6c2c02cae34de33367e1effdf76
 F src/parse.y 12b7ebd61ea54f0e1b1083ff69cc2c8ce9353d58
 F src/pcache.c 09d38c44ab275db581f7a2f6ff8b9bc7f8c0faaa
@@ -897,7 +900,14 @@ F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
 F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
 F tool/vdbe-compress.tcl d70ea6d8a19e3571d7ab8c9b75cba86d1173ff0f
-P 35ac78f55159705af140b949ee33852aedd62816
-R 5a38d0e5da35229b881ee437e0399faf
-U dan
-Z ba9abebf804867e3ebdd758398513a6b
+P 58577135a81d3f19667b1de6167d2e3f1b74cd53
+R a0c65f35bd8df31841c75a033fdc54e1
+U drh
+Z afe8bfe1fbfd780cf630a681a38fd2a0
+-----BEGIN PGP SIGNATURE-----
+Version: GnuPG v1.4.6 (GNU/Linux)
+
+iD8DBQFNQuTKoxKgR168RlERArXfAJ9CQ6LWQKMuWD1biGnn8WGHHeKjNwCdFcPT
+8yNpIIrDf9AAFFFQY8m1usg=
+=moCk
+-----END PGP SIGNATURE-----
diff --git a/manifest.uuid b/manifest.uuid
index 48857721c8..5637a09f93 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-58577135a81d3f19667b1de6167d2e3f1b74cd53
\ No newline at end of file
+874bc8844f6494cdbf700bd884dee67d40f11fc0
\ No newline at end of file
diff --git a/src/pager.c b/src/pager.c
index 1378323126..80f3b0e771 100644
--- a/src/pager.c
+++ b/src/pager.c
@@ -2477,20 +2477,21 @@ static int pager_truncate(Pager *pPager, Pgno nPage){
    && (pPager->eState>=PAGER_WRITER_DBMOD || pPager->eState==PAGER_OPEN) 
   ){
     i64 currentSize, newSize;
+    int szPage = pPager->pageSize;
     assert( pPager->eLock==EXCLUSIVE_LOCK );
     /* TODO: Is it safe to use Pager.dbFileSize here? */
     rc = sqlite3OsFileSize(pPager->fd, &currentSize);
-    newSize = pPager->pageSize*(i64)nPage;
+    newSize = szPage*(i64)nPage;
     if( rc==SQLITE_OK && currentSize!=newSize ){
       if( currentSize>newSize ){
         rc = sqlite3OsTruncate(pPager->fd, newSize);
       }else{
         char *pTmp = pPager->pTmpSpace;
-        memset(pTmp, 0, pPager->pageSize);
-        while( currentSize<newSize ){
-          rc = sqlite3OsWrite(pPager->fd, pTmp, pPager->pageSize, currentSize);
-          currentSize += pPager->pageSize;
-        }
+        memset(pTmp, 0, szPage);
+        testcase( (newSize-szPage) <  currentSize );
+        testcase( (newSize-szPage) == currentSize );
+        testcase( (newSize-szPage) >  currentSize );
+        rc = sqlite3OsWrite(pPager->fd, pTmp, szPage, newSize-szPage);
       }
       if( rc==SQLITE_OK ){
         pPager->dbFileSize = nPage;