Avoid harmless integer overflow in pager status statistics gathering.

Response to [forum:/forumpost/7f4cdf23f9|forum post 7f4cdf23f9].

FossilOrigin-Name: 206d8c650d937bc700946c40a82a62ea6bc4a80e5f3fb42d0ae2968de25f0644

manifest

@@ -1,5 +1,5 @@
-C In\sJSON\s-\sminor\scode\scleanup\sand\srefactoring\swith\sa\ssmall\ssize\sreduction\nand\sperformance\sincrease.
-D 2023-12-19T21:39:58.157
+C Avoid\sharmless\sinteger\soverflow\sin\spager\sstatus\sstatistics\sgathering.\nResponse\sto\s[forum:/forumpost/7f4cdf23f9|forum\spost\s7f4cdf23f9].
+D 2023-12-20T11:34:17.563
 F .fossil-settings/empty-dirs dbb81e8fc0401ac46a1491ab34a7f2c7c0452f2f06b54ebb845d024ca8283ef1
 F .fossil-settings/ignore-glob 35175cdfcf539b2318cb04a9901442804be81cd677d8b889fcc9149c21f239ea
 F LICENSE.md df5091916dbb40e6e9686186587125e1b2ff51f022cc334e886c19a0e9982724
@@ -723,8 +723,8 @@ F src/os_setup.h 6011ad7af5db4e05155f385eb3a9b4470688de6f65d6166b8956e58a3d87210
 F src/os_unix.c 97bdcd43315da7aaec9fea2da1ff7c9de458f93dd363e073f2742403a7f2e011
 F src/os_win.c 4a50a154aeebc66a1f8fb79c1ff6dd5fe3d005556533361e0d460d41cb6a45a8
 F src/os_win.h 7b073010f1451abe501be30d12f6bc599824944a
-F src/pager.c 987ab3a2cd9065d62e9955474470ff733445e2357432a67e3d0f5a8f9313e334
-F src/pager.h f4d33fec8052603758792045493423b8871a996da2d0973927b7d36cd6070473
+F src/pager.c dc0cccda12d1675f461ef47090ec6bd7bb7611e77dbf5e0796667120d9b67f37
+F src/pager.h 4b1140d691860de0be1347474c51fee07d5420bd7f802d38cbab8ea4ab9f538a
 F src/parse.y 020d80386eb216ec9520549106353c517d2bbc89be28752ffdca649a9eaf56ec
 F src/pcache.c 040b165f30622a21b7a9a77c6f2e4877a32fb7f22d4c7f0d2a6fa6833a156a75
 F src/pcache.h 1497ce1b823cf00094bb0cf3bac37b345937e6f910890c626b16512316d3abf5
@@ -743,7 +743,7 @@ F src/sqlite3.rc 5121c9e10c3964d5755191c80dd1180c122fc3a8
 F src/sqlite3ext.h 3f046c04ea3595d6bfda99b781926b17e672fd6d27da2ba6d8d8fc39981dcb54
 F src/sqliteInt.h 134457f62bb1d0ff1dd037cc23dd46b1d16efbbfc2211dc2b15c380af731d9ac
 F src/sqliteLimit.h 33b1c9baba578d34efe7dfdb43193b366111cdf41476b1e82699e14c11ee1fb6
-F src/status.c 160c445d7d28c984a0eae38c144f6419311ed3eace59b44ac6dafc20db4af749
+F src/status.c cb11f8589a6912af2da3bb1ec509a94dd8ef27df4d4c1a97e0bcf2309ece972b
 F src/table.c 0f141b58a16de7e2fbe81c308379e7279f4c6b50eb08efeec5892794a0ba30d1
 F src/tclsqlite.c ecbc3c99c0d0c3ed122a913f143026c26d38d57f33e06bb71185dd5c1efe37cd
 F src/test1.c ac6542cddd1f405e332d869946b977b2ce8b4dc28b9f7cc61df38abe1fe49bc3
@@ -2155,8 +2155,8 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P 257f96a2d22c605885fa66220c28cf7dc5941c330bccee3f132b9e7b70d89d30
-R 1e43c523c137344cae8cdc90cc8b1706
+P 215fabda38daecdbd38b1eca5a6aafbc61b6a36a8303f1d7164d5a1138e63134
+R d4f2caa7842856e1d7a2268ee871a371
 U drh
-Z 35aaca72ca93a246000bef5de54a54bb
+Z 1d76cf71ba5b0710fab4dfb939c1e975
 # Remove this line to create a well-formed Fossil manifest.

manifest.uuid

@@ -1 +1 @@
-215fabda38daecdbd38b1eca5a6aafbc61b6a36a8303f1d7164d5a1138e63134
+206d8c650d937bc700946c40a82a62ea6bc4a80e5f3fb42d0ae2968de25f0644

src/pager.c

@@ -688,7 +688,7 @@ struct Pager {
   char *zJournal;             /* Name of the journal file */
   int (*xBusyHandler)(void*); /* Function to call when busy */
   void *pBusyHandlerArg;      /* Context argument for xBusyHandler */
-  int aStat[4];               /* Total cache hits, misses, writes, spills */
+  u32 aStat[4];               /* Total cache hits, misses, writes, spills */
 #ifdef SQLITE_TEST
   int nRead;                  /* Database pages read */
 #endif
@@ -6832,11 +6832,11 @@ int *sqlite3PagerStats(Pager *pPager){
   a[3] = pPager->eState==PAGER_OPEN ? -1 : (int) pPager->dbSize;
   a[4] = pPager->eState;
   a[5] = pPager->errCode;
-  a[6] = pPager->aStat[PAGER_STAT_HIT];
-  a[7] = pPager->aStat[PAGER_STAT_MISS];
+  a[6] = (int)pPager->aStat[PAGER_STAT_HIT] & 0x7fffffff;
+  a[7] = (int)pPager->aStat[PAGER_STAT_MISS] & 0x7fffffff;
   a[8] = 0;  /* Used to be pPager->nOvfl */
   a[9] = pPager->nRead;
-  a[10] = pPager->aStat[PAGER_STAT_WRITE];
+  a[10] = (int)pPager->aStat[PAGER_STAT_WRITE] & 0x7fffffff;
   return a;
 }
 #endif
@@ -6852,7 +6852,7 @@ int *sqlite3PagerStats(Pager *pPager){
 ** reset parameter is non-zero, the cache hit or miss count is zeroed before
 ** returning.
 */
-void sqlite3PagerCacheStat(Pager *pPager, int eStat, int reset, int *pnVal){
+void sqlite3PagerCacheStat(Pager *pPager, int eStat, int reset, u64 *pnVal){
 
   assert( eStat==SQLITE_DBSTATUS_CACHE_HIT
        || eStat==SQLITE_DBSTATUS_CACHE_MISS

src/pager.h

@@ -216,7 +216,7 @@ sqlite3_file *sqlite3PagerJrnlFile(Pager*);
 const char *sqlite3PagerJournalname(Pager*);
 void *sqlite3PagerTempSpace(Pager*);
 int sqlite3PagerIsMemdb(Pager*);
-void sqlite3PagerCacheStat(Pager *, int, int, int *);
+void sqlite3PagerCacheStat(Pager *, int, int, u64*);
 void sqlite3PagerClearCache(Pager*);
 int sqlite3SectorSize(sqlite3_file *);
 

src/status.c

@@ -362,7 +362,7 @@ int sqlite3_db_status(
     case SQLITE_DBSTATUS_CACHE_MISS:
     case SQLITE_DBSTATUS_CACHE_WRITE:{
       int i;
-      int nRet = 0;
+      u64 nRet = 0;
       assert( SQLITE_DBSTATUS_CACHE_MISS==SQLITE_DBSTATUS_CACHE_HIT+1 );
       assert( SQLITE_DBSTATUS_CACHE_WRITE==SQLITE_DBSTATUS_CACHE_HIT+2 );
 
@@ -375,7 +375,7 @@ int sqlite3_db_status(
       *pHighwater = 0; /* IMP: R-42420-56072 */
                        /* IMP: R-54100-20147 */
                        /* IMP: R-29431-39229 */
-      *pCurrent = nRet;
+      *pCurrent = (int)nRet & 0x7fffffff;
       break;
     }