From 0e7b492943ec8cfdc7fffd9304d496315f781ea7 Mon Sep 17 00:00:00 2001
From: Willy Tarreau <w@1wt.eu>
Date: Mon, 21 Mar 2022 18:33:10 +0100
Subject: [PATCH] tools/nolibc/string: add strcmp() and strncmp()
We need these functions all the time, including when checking environment
variables and parsing command-line arguments. These implementations were
optimized to show optimal code size on a wide range of compilers (22 bytes
return included for strcmp(), 33 for strncmp()).
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
---
tools/include/nolibc/string.h | 23 +++++++++++++++++++++++
1 file changed, 23 insertions(+)
diff --git a/tools/include/nolibc/string.h b/tools/include/nolibc/string.h
index 4554b6fcb4009..0d5e870c7c0b9 100644
--- a/tools/include/nolibc/string.h
+++ b/tools/include/nolibc/string.h
@@ -102,6 +102,17 @@ char *strchr(const char *s, int c)
return NULL;
}
+static __attribute__((unused))
+int strcmp(const char *a, const char *b)
+{
+ unsigned int c;
+ int diff;
+
+ while (!(diff = (unsigned char)*a++ - (c = (unsigned char)*b++)) && c)
+ ;
+ return diff;
+}
+
static __attribute__((unused))
char *strcpy(char *dst, const char *src)
{
@@ -184,6 +195,18 @@ char *strncat(char *dst, const char *src, size_t size)
return orig;
}
+static __attribute__((unused))
+int strncmp(const char *a, const char *b, size_t size)
+{
+ unsigned int c;
+ int diff = 0;
+
+ while (size-- &&
+ !(diff = (unsigned char)*a++ - (c = (unsigned char)*b++)) && c)
+ ;
+
+ return diff;
+}
static __attribute__((unused))
char *strncpy(char *dst, const char *src, size_t size)
--
2.30.2