From 397c902d7eb8c250bbc480f826cc873e287f94c7 Mon Sep 17 00:00:00 2001
From: Paweł Redman <pawel.redman@gmail.com>
Date: Fri, 7 Apr 2017 12:34:39 +0200
Subject: Fix a potential NULL pointer dereference.

---
 src/lexer.c  | 5 ++++-
 src/shared.h | 2 +-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/lexer.c b/src/lexer.c
index 5863ef6..a3d5b61 100644
--- a/src/lexer.c
+++ b/src/lexer.c
@@ -85,8 +85,11 @@ char *vstr_strdup(vstr_t *vstr)
 	return str;
 }
 
-char *vstr_to_cstr(vstr_t *vstr)
+const char *vstr_to_cstr(vstr_t *vstr)
 {
+	if (!vstr->size)
+		return NULL;
+
 	vstr->data[vstr->size] = '\0';
 	return vstr->data;
 }
diff --git a/src/shared.h b/src/shared.h
index bf4adeb..1554ce9 100644
--- a/src/shared.h
+++ b/src/shared.h
@@ -131,7 +131,7 @@ void vstr_clear(vstr_t *vstr);
 int vstr_putc(vstr_t *vstr, char ch);
 int vstr_cmp(vstr_t *vstr, const char *str);
 char *vstr_strdup(vstr_t *vstr);
-char *vstr_to_cstr(vstr_t *vstr);
+const char *vstr_to_cstr(vstr_t *vstr);
 
 #define LEXER_BUFFER 1024
 
-- 
cgit