From 5a737917b00a76936c1b50b39ac95732fa5d0c1a Mon Sep 17 00:00:00 2001
From: "K. Lange" <klange@toaruos.org>
Date: Fri, 4 May 2018 12:21:52 +0900
Subject: [PATCH] strncmp

---
 base/usr/include/string.h |  1 +
 libc/string/strncmp.c     | 13 +++++++++++++
 2 files changed, 14 insertions(+)
 create mode 100644 libc/string/strncmp.c

diff --git a/base/usr/include/string.h b/base/usr/include/string.h
index 1c568aaf..3f963a1a 100644
--- a/base/usr/include/string.h
+++ b/base/usr/include/string.h
@@ -25,6 +25,7 @@ extern char * strpbrk(const char * s, const char * b);
 extern char * strstr(const char * h, const char * n);
 
 extern int strcmp(const char * l, const char * r);
+extern int strncmp(const char *s1, const char *s2, size_t n);
 
 extern size_t strcspn(const char * s, const char * c);
 extern size_t strspn(const char * s, const char * c);
diff --git a/libc/string/strncmp.c b/libc/string/strncmp.c
new file mode 100644
index 00000000..2bd0f810
--- /dev/null
+++ b/libc/string/strncmp.c
@@ -0,0 +1,13 @@
+#include <string.h>
+
+int strncmp(const char *s1, const char *s2, size_t n) {
+	size_t i = 0;
+	while (i < n && *s1 && *s2) {
+		if (*s1 < *s2) return -1;
+		if (*s1 > *s2) return 1;
+		s1++;
+		s2++;
+		i++;
+	}
+	return 0;
+}