String-handling functions for the new x86 setup code.

strcmp(), memcpy(), memset(), as well as routines to copy to and from
other segments (as pointed to by fs and gs).

Signed-off-by: H. Peter Anvin <hpa@zytor.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 52 insertions, 0 deletions

diff --git a/arch/i386/boot/string.c b/arch/i386/boot/string.c
new file mode 100644
index 0000000..481a220
--- /dev/null
+++ b/arch/i386/boot/string.c
@@ -0,0 +1,52 @@
+/* -*- linux-c -*- ------------------------------------------------------- *
+ *
+ *   Copyright (C) 1991, 1992 Linus Torvalds
+ *   Copyright 2007 rPath, Inc. - All Rights Reserved
+ *
+ *   This file is part of the Linux kernel, and is made available under
+ *   the terms of the GNU General Public License version 2.
+ *
+ * ----------------------------------------------------------------------- */
+
+/*
+ * arch/i386/boot/string.c
+ *
+ * Very basic string functions
+ */
+
+#include "boot.h"
+
+int strcmp(const char *str1, const char *str2)
+{
+	const unsigned char *s1 = (const unsigned char *)str1;
+	const unsigned char *s2 = (const unsigned char *)str2;
+	int delta = 0;
+
+	while (*s1 || *s2) {
+		delta = *s2 - *s1;
+		if (delta)
+			return delta;
+		s1++;
+		s2++;
+	}
+	return 0;
+}
+
+size_t strnlen(const char *s, size_t maxlen)
+{
+	const char *es = s;
+	while (*es && maxlen) {
+		es++;
+		maxlen--;
+	}
+
+	return (es - s);
+}
+
+unsigned int atou(const char *s)
+{
+	unsigned int i = 0;
+	while (isdigit(*s))
+		i = i * 10 + (*s++ - '0');
+	return i;
+}