Import SQLite 3.7.6.3.

third_party/sqlite/src/ext/async/sqlite3async.c

Index: third_party/sqlite/src/ext/async/sqlite3async.c
diff --git a/third_party/sqlite/src/ext/async/sqlite3async.c b/third_party/sqlite/src/ext/async/sqlite3async.c
index 11a4761298cffd4c4c9510a0aecc25bccfd75083..a351eaa92261ebc48177fe716713f2207edae419 100644
--- a/third_party/sqlite/src/ext/async/sqlite3async.c
+++ b/third_party/sqlite/src/ext/async/sqlite3async.c
@@ -667,9 +667,9 @@ static int asyncRead(
 ){
   AsyncFileData *p = ((AsyncFile *)pFile)->pData;
   int rc = SQLITE_OK;
-  sqlite3_int64 filesize;
-  int nRead;
+  sqlite3_int64 filesize = 0;
   sqlite3_file *pBase = p->pBaseRead;
+  sqlite3_int64 iAmt64 = (sqlite3_int64)iAmt;
 
   /* Grab the write queue mutex for the duration of the call */
   async_mutex_enter(ASYNC_MUTEX_QUEUE);
@@ -683,13 +683,14 @@ static int asyncRead(
   }
 
   if( pBase->pMethods ){
+    sqlite3_int64 nRead;
     rc = pBase->pMethods->xFileSize(pBase, &filesize);
     if( rc!=SQLITE_OK ){
       goto asyncread_out;
     }
-    nRead = (int)MIN(filesize - iOffset, iAmt);
+    nRead = MIN(filesize - iOffset, iAmt64);
     if( nRead>0 ){
-      rc = pBase->pMethods->xRead(pBase, zOut, nRead, iOffset);
+      rc = pBase->pMethods->xRead(pBase, zOut, (int)nRead, iOffset);
       ASYNC_TRACE(("READ %s %d bytes at %d\n", p->zName, nRead, iOffset));
     }
   }
@@ -703,16 +704,24 @@ static int asyncRead(
         (pWrite->pFileData==p) ||
         (zName && pWrite->pFileData->zName==zName)
       )){
+        sqlite3_int64 nCopy;
+        sqlite3_int64 nByte64 = (sqlite3_int64)pWrite->nByte;
+
+        /* Set variable iBeginIn to the offset in buffer pWrite->zBuf[] from
+        ** which data should be copied. Set iBeginOut to the offset within
+        ** the output buffer to which data should be copied. If either of
+        ** these offsets is a negative number, set them to 0.
+        */
         sqlite3_int64 iBeginOut = (pWrite->iOffset-iOffset);
         sqlite3_int64 iBeginIn = -iBeginOut;
-        int nCopy;
-
         if( iBeginIn<0 ) iBeginIn = 0;
         if( iBeginOut<0 ) iBeginOut = 0;
-        nCopy = (int)MIN(pWrite->nByte-iBeginIn, iAmt-iBeginOut);
 
+        filesize = MAX(filesize, pWrite->iOffset+nByte64);
+
+        nCopy = MIN(nByte64-iBeginIn, iAmt64-iBeginOut);
         if( nCopy>0 ){
-          memcpy(&((char *)zOut)[iBeginOut], &pWrite->zBuf[iBeginIn], nCopy);
+          memcpy(&((char *)zOut)[iBeginOut], &pWrite->zBuf[iBeginIn], (size_t)nCopy);
           ASYNC_TRACE(("OVERREAD %d bytes at %d\n", nCopy, iBeginOut+iOffset));
         }
       }
@@ -721,6 +730,9 @@ static int asyncRead(
 
 asyncread_out:
   async_mutex_leave(ASYNC_MUTEX_QUEUE);
+  if( rc==SQLITE_OK && filesize<(iOffset+iAmt) ){
+    rc = SQLITE_IOERR_SHORT_READ;
+  }
   return rc;
 }
 
@@ -1131,7 +1143,6 @@ static int asyncOpen(
   async_mutex_leave(ASYNC_MUTEX_LOCK);
 
   if( rc==SQLITE_OK ){
-    incrOpenFileCount();
     pData->pLock = pLock;
   }
 
@@ -1148,7 +1159,10 @@ static int asyncOpen(
   }
   if( rc!=SQLITE_OK ){
     p->pMethod = 0;
+  }else{
+    incrOpenFileCount();
   }
+
   return rc;
 }
 
@@ -1224,8 +1238,8 @@ static int asyncFullPathname(
   */
   if( rc==SQLITE_OK ){
     int i, j;
-    int n = nPathOut;
     char *z = zPathOut;
+    int n = (int)strlen(z);
     while( n>1 && z[n-1]=='/' ){ n--; }
     for(i=j=0; i<n; i++){
       if( z[i]=='/' ){