libc: fwrite: bail quickly if size calcs to 0

2018-10-12 13:50:53 +09:00 · 2018-10-12 13:50:53 +09:00 · 5de060b1d5
commit 5de060b1d5
parent e492f967c0
1 changed files with 2 additions and 0 deletions
--- a/libc/stdio/stdio.c
+++ b/libc/stdio/stdio.c
@ -319,6 +319,8 @@ size_t fread(void *ptr, size_t size, size_t nmemb, FILE * stream) {
 size_t fwrite(const void *ptr, size_t size, size_t nmemb, FILE * stream) {
 	size_t out_size = size * nmemb;

+	if (!out_size) return 0;
+
 	int r = syscall_write(stream->fd, (void*)ptr, out_size);
 	if (r < 0) {
 		errno = -r;