Make linux kernel string funcs available to tools

isspace() and strim() are not in the typical user-mode string.h, so
put them in a separate compilation unit so that they can be built into
tools that need them independent of the other common string functions.

This allows code shared by u-boot and the linux user-mode tools to link.

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>

include/linux/linux_string.h

@@ -0,0 +1,8 @@
+#ifndef _LINUX_LINUX_STRING_H_
+#define _LINUX_LINUX_STRING_H_
+
+extern char * skip_spaces(const char *);
+
+extern char *strim(char *);
+
+#endif

include/linux/string.h

@@ -50,10 +50,7 @@ extern char * strchr(const char *,int);
 #ifndef __HAVE_ARCH_STRRCHR
 extern char * strrchr(const char *,int);
 #endif
-extern char * skip_spaces(const char *);
-
-extern char *strim(char *);
-
+#include <linux/linux_string.h>
 #ifndef __HAVE_ARCH_STRSTR
 extern char * strstr(const char *,const char *);
 #endif

lib/Makefile

@@ -69,6 +69,7 @@ endif
 COBJS-y += crc32.o
 COBJS-y += ctype.o
 COBJS-y += div64.o
+COBJS-y += linux_string.o
 COBJS-y += string.o
 COBJS-y += time.o
 COBJS-$(CONFIG_BOOTP_PXE) += uuid.o

lib/linux_string.c

@@ -0,0 +1,51 @@
+/*
+ *  linux/lib/string.c
+ *
+ *  Copyright (C) 1991, 1992  Linus Torvalds
+ */
+
+#ifdef USE_HOSTCC
+#include <stdio.h>
+#endif
+
+#include <linux/ctype.h>
+#include <linux/string.h>
+
+/**
+ * skip_spaces - Removes leading whitespace from @str.
+ * @str: The string to be stripped.
+ *
+ * Returns a pointer to the first non-whitespace character in @str.
+ */
+char *skip_spaces(const char *str)
+{
+	while (isspace(*str))
+		++str;
+	return (char *)str;
+}
+
+/**
+ * strim - Removes leading and trailing whitespace from @s.
+ * @s: The string to be stripped.
+ *
+ * Note that the first trailing whitespace is replaced with a %NUL-terminator
+ * in the given string @s. Returns a pointer to the first non-whitespace
+ * character in @s.
+ */
+char *strim(char *s)
+{
+	size_t size;
+	char *end;
+
+	s = skip_spaces(s);
+	size = strlen(s);
+	if (!size)
+		return s;
+
+	end = s + size - 1;
+	while (end >= s && isspace(*end))
+		end--;
+	*(end + 1) = '\0';
+
+	return s;
+}

lib/string.c

@@ -222,45 +222,6 @@ char * strrchr(const char * s, int c)
 }
 #endif
 
-
-/**
- * skip_spaces - Removes leading whitespace from @str.
- * @str: The string to be stripped.
- *
- * Returns a pointer to the first non-whitespace character in @str.
- */
-char *skip_spaces(const char *str)
-{
-	while (isspace(*str))
-		++str;
-	return (char *)str;
-}
-
-/**
- * strim - Removes leading and trailing whitespace from @s.
- * @s: The string to be stripped.
- *
- * Note that the first trailing whitespace is replaced with a %NUL-terminator
- * in the given string @s. Returns a pointer to the first non-whitespace
- * character in @s.
- */
-char *strim(char *s)
-{
-	size_t size;
-	char *end;
-
-	s = skip_spaces(s);
-	size = strlen(s);
-	if (!size)
-		return s;
-
-	end = s + size - 1;
-	while (end >= s && isspace(*end))
-		end--;
-	*(end + 1) = '\0';
-
-	return s;
-}
 #ifndef __HAVE_ARCH_STRLEN
 /**
  * strlen - Find the length of a string