Split out is_printable_string() into util.c

This useful function is split out so it will be available to programs
other than ftdump.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: David Gibson <david@gibson.dropbear.id.au>

Makefile.ftdump

@@ -5,7 +5,8 @@
 #
 
 FTDUMP_SRCS = \
-	ftdump.c
+	ftdump.c \
+	util.c
 
 FTDUMP_GEN_SRCS =
 

ftdump.c

@@ -11,36 +11,14 @@
 #include <fdt.h>
 #include <libfdt_env.h>
 
+#include "util.h"
+
 #define FTDUMP_BUF_SIZE	65536
 
 #define ALIGN(x, a)	(((x) + ((a) - 1)) & ~((a) - 1))
 #define PALIGN(p, a)	((void *)(ALIGN((unsigned long)(p), (a))))
 #define GET_CELL(p)	(p += 4, *((const uint32_t *)(p-4)))
 
-static int is_printable_string(const void *data, int len)
-{
-	const char *s = data;
-	const char *ss;
-
-	/* zero length is not */
-	if (len == 0)
-		return 0;
-
-	/* must terminate with zero */
-	if (s[len - 1] != '\0')
-		return 0;
-
-	ss = s;
-	while (*s && isprint(*s))
-		s++;
-
-	/* not zero, or not done yet */
-	if (*s != '\0' || (s + 1 - ss) < len)
-		return 0;
-
-	return 1;
-}
-
 static void print_data(const char *data, int len)
 {
 	int i;
@@ -50,7 +28,7 @@ static void print_data(const char *data, int len)
 	if (len == 0)
 		return;
 
-	if (is_printable_string(data, len)) {
+	if (util_is_printable_string(data, len)) {
 		printf(" = \"%s\"", (const char *)data);
 	} else if ((len % 4) == 0) {
 		printf(" = <");

util.c

@@ -1,6 +1,9 @@
 /*
  * Copyright 2008 Jon Loeliger, Freescale Semiconductor, Inc.
  *
+ * util_is_printable_string contributed by
+ *	Pantelis Antoniou <pantelis.antoniou AT gmail.com>
+ *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License as
  * published by the Free Software Foundation; either version 2 of the
@@ -17,6 +20,7 @@
  *                                                                   USA
  */
 
+#include <ctype.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdarg.h>
@@ -57,3 +61,27 @@ char *join_path(const char *path, const char *name)
 	memcpy(str+lenp, name, lenn+1);
 	return str;
 }
+
+int util_is_printable_string(const void *data, int len)
+{
+	const char *s = data;
+	const char *ss;
+
+	/* zero length is not */
+	if (len == 0)
+		return 0;
+
+	/* must terminate with zero */
+	if (s[len - 1] != '\0')
+		return 0;
+
+	ss = s;
+	while (*s && isprint(*s))
+		s++;
+
+	/* not zero, or not done yet */
+	if (*s != '\0' || (s + 1 - ss) < len)
+		return 0;
+
+	return 1;
+}

util.h

@@ -1,6 +1,8 @@
 #ifndef _UTIL_H
 #define _UTIL_H
 
+#include <stdarg.h>
+
 /*
  * Copyright 2008 Jon Loeliger, Freescale Semiconductor, Inc.
  *
@@ -53,4 +55,13 @@ static inline void *xrealloc(void *p, size_t len)
 extern char *xstrdup(const char *s);
 extern char *join_path(const char *path, const char *name);
 
+/**
+ * Check a string of a given length to see if it is all printable and
+ * has a valid terminator.
+ *
+ * @param data	The string to check
+ * @param len	The string length including terminator
+ * @return 1 if a valid printable string, 0 if not */
+int util_is_printable_string(const void *data, int len);
+
 #endif /* _UTIL_H */