[sql] Rewrite sqlite patching "system".

third_party/sqlite/amalgamation/sqlite3.c

Index: third_party/sqlite/amalgamation/sqlite3.c
diff --git a/third_party/sqlite/amalgamation/sqlite3.c b/third_party/sqlite/amalgamation/sqlite3.c
index 16a136b32481d3be473fbbad824027ed12765dcc..22092947bb57ea0d87af037357ed594e66bcfa90 100644
--- a/third_party/sqlite/amalgamation/sqlite3.c
+++ b/third_party/sqlite/amalgamation/sqlite3.c
@@ -82813,7 +82813,7 @@ static void trimFunc(
       }
     }
     if( zCharSet ){
-      sqlite3_free((void*)azChar);
+      sqlite3_free(azChar);
     }
   }
   sqlite3_result_text(context, (char*)zIn, nIn, SQLITE_TRANSIENT);
@@ -109241,6 +109241,14 @@ static int openDatabase(
   }
 #endif
 
+#ifdef DEFAULT_ENABLE_RECOVER
+  /* Initialize recover virtual table for testing. */
+  extern int recoverVtableInit(sqlite3 *db);
+  if( !db->mallocFailed && rc==SQLITE_OK ){
+    rc = recoverVtableInit(db);
+  }
+#endif
+
 #ifdef SQLITE_ENABLE_ICU
   if( !db->mallocFailed && rc==SQLITE_OK ){
     rc = sqlite3IcuInit(db);
@@ -110904,12 +110912,18 @@ static void interiorCursorSetPage(RecoverInteriorCursor *pCursor,
   pCursor->nChildren = decodeUnsigned16(PageHeader(pPage) +
                                         kiPageCellCountOffset) + 1;
 
-  /* The maximum possible value for nChildren is:
+  /* Each child requires a 16-bit offset from an array after the header,
+   * and each child contains a 32-bit page number and at least a varint
+   * (min size of one byte).  The final child page is in the header.  So
+   * the maximum value for nChildren is:
    *   (nPageSize - kiPageInteriorHeaderBytes) /
    *      (sizeof(uint16) + sizeof(uint32) + 1) + 1
-   * Each child requires a 16-bit offset from an array after the header, and
-   * each child contains a 32-bit page number and at least a varint (min size of
-   * one byte).  The final child page is in the header.
+   */
+  /* TODO(shess): This count is very unlikely to be corrupted in
+   * isolation, so seeing this could signal to skip the page.  OTOH, I
+   * can't offhand think of how to get here unless this or the page-type
+   * byte is corrupted.  Could be an overflow page, but it would require
+   * a very large database.
    */
   nMaxChildren =
       (pCursor->nPageSize - kiPageInteriorHeaderBytes) / knMinCellLength + 1;