wrap-json: Fix bug decoding empty base64

The function 'decode_base64' was buggy because
it freed 2 times the pointer 'result'.
This came from the fact realloc frees the
pointer and return NULL when the size if 0.

Signed-off-by: jobol <jose.bollo@iot.bzh>

diff --git a/wrap-json.c b/wrap-json.c
index 6c4da7b..11fdd8c 100644 (file)
--- a/wrap-json.c
+++ b/wrap-json.c
@@ -241,7 +241,7 @@ static int decode_base64(
 
        /* terminate */
        *decoded = realloc(result, out);
-       if (*decoded == NULL) {
+       if (out && *decoded == NULL) {
                free(result);
                return wrap_json_error_out_of_memory;
        }
@@ -1134,6 +1134,7 @@ int main()
 
        U("\"Pz8_Pz8_P2hlbGxvPj4-Pj4-Pg\"", "y", &xy[0], &xz[0]);
        U("{\"foo\":\"Pz8_Pz8_P2hlbGxvPj4-Pj4-Pg\"}", "{s?y}", "foo", &xy[0], &xz[0]);
+       U("{\"foo\":\"\"}", "{s?y}", "foo", &xy[0], &xz[0]);
        U("{}", "{s?y}", "foo", &xy[0], &xz[0]);
        return 0;
 }