From 932bfb38a146388be8639db9af49134640b7e486 Mon Sep 17 00:00:00 2001
From: vms <michail.vms@gmail.com>
Date: Mon, 12 Apr 2021 14:45:55 +0300
Subject: [PATCH] final preparation

---
 sqlite3.wit     |  2 +-
 src/legacy.c    |  2 +-
 src/main.c      |  5 ++---
 src/sqliteInt.h |  2 ++
 src/wrapper.c   | 11 +++++++++++
 5 files changed, 17 insertions(+), 5 deletions(-)

diff --git a/sqlite3.wit b/sqlite3.wit
index 3425838..b726881 100644
--- a/sqlite3.wit
+++ b/sqlite3.wit
@@ -1,4 +1,4 @@
-(@interface it_version "0.19.0"
+(@interface it_version "0.19.0")
 
 ;; Types
 (@interface type (func
diff --git a/src/legacy.c b/src/legacy.c
index a4437cb..b931790 100644
--- a/src/legacy.c
+++ b/src/legacy.c
@@ -35,7 +35,7 @@ void sqlite3_exec_(
   sqlite3_callback xCallback, /* Invoke this callback routine */
   void *pArg                  /* First argument to xCallback() */
 ) __EXPORT_NAME(sqlite3_exec) {
-  zSql[zSql_len] = '\x00';
+  zSql = handle_input_string(zSql, zSql_len);
 
   char *pzErrMsg = 0;
   const int ret_code = sqlite3_exec(db, zSql, xCallback, pArg, &pzErrMsg);
diff --git a/src/main.c b/src/main.c
index 18e568a..aed5dc8 100644
--- a/src/main.c
+++ b/src/main.c
@@ -3443,9 +3443,8 @@ void sqlite3_open_v2_(
   char *zVfs,             /* Name of VFS module to use */
   int zVfs_len
 ) __EXPORT_NAME(sqlite3_open_v2) {
-  // this strings were allocated by the allocate function that allocates 1 byte more for null character
-  filename[filename_len] = '\x00';
-  zVfs[zVfs_len] = '\x00';
+  filename = handle_input_string(filename, filename_len);
+  zVfs = handle_input_string(zVfs, zVfs_len);
 
   sqlite3 *ppDb;
 
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 07d7b43..64261f9 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -4913,6 +4913,8 @@ void add_object_to_release(void *object);
 
 void set_result_ptr(void *ptr);
 void set_result_size(int size);
+
+char *handle_input_string(char *str, int len);
 #endif
 
 #endif /* SQLITEINT_H */
diff --git a/src/wrapper.c b/src/wrapper.c
index 0a2a787..9ff30d8 100644
--- a/src/wrapper.c
+++ b/src/wrapper.c
@@ -43,6 +43,17 @@ void *get_result_ptr() {
   return RESULT_PTR;
 }
 
+char *handle_input_string(char *str, int len) {
+  if (len == 0) {
+    free(str);
+    return NULL;
+  }
+
+  // this strings are supposed to be allocated by the allocate function, which allocates 1 byte more for null character
+  str[len] = '\x00';
+  return str;
+}
+
 int main() {
   // the main purpose of this empty main is to initialize WASI subsystem
   return 0;