vfs, seqfile: make mangle_path() global

Impact: expose new VFS API

make mangle_path() available, as per the suggestions of Christoph Hellwig
and Al Viro:

  http://lkml.org/lkml/2008/11/4/338Signed-off-by: NTörök Edwin <edwintorok@gmail.com>
Signed-off-by: NIngo Molnar <mingo@elte.hu>

fs/seq_file.c

@@ -357,7 +357,18 @@ int seq_printf(struct seq_file *m, const char *f, ...)
 }
 EXPORT_SYMBOL(seq_printf);
 
-static char *mangle_path(char *s, char *p, char *esc)
+/**
+ * 	mangle_path - mangle and copy path to buffer beginning
+ * 	@s - buffer start
+ * 	@p - beginning of path in above buffer
+ *      @esc - set of characters that need escaping
+ *
+ *      Copy the path from @p to @s, replacing each occurrence of character from
+ *      @esc with usual octal escape.
+ *      Returns pointer past last written character in @s, or NULL in case of
+ *      failure.
+ */
+char *mangle_path(char *s, char *p, char *esc)
 {
 	while (s <= p) {
 		char c = *p++;
@@ -376,6 +387,7 @@ static char *mangle_path(char *s, char *p, char *esc)
 	}
 	return NULL;
 }
+EXPORT_SYMBOL_GPL(mangle_path);
 
 /*
  * return the absolute path of 'dentry' residing in mount 'mnt'.

include/linux/seq_file.h

@@ -34,6 +34,7 @@ struct seq_operations {
 
 #define SEQ_SKIP 1
 
+char *mangle_path(char *s, char *p, char *esc);
 int seq_open(struct file *, const struct seq_operations *);
 ssize_t seq_read(struct file *, char __user *, size_t, loff_t *);
 loff_t seq_lseek(struct file *, loff_t, int);