cifs: add new function to get unicode string length in bytes

[pandora-kernel.git] / fs / cifs / cifs_unicode.c

diff --git a/fs/cifs/cifs_unicode.c b/fs/cifs/cifs_unicode.c
index 8389f35..6145125 100644 (file)
--- a/fs/cifs/cifs_unicode.c
+++ b/fs/cifs/cifs_unicode.c
@@ -25,6 +25,37 @@
 #include "cifsglob.h"
 #include "cifs_debug.h"
 
+/*
+ * cifs_ucs2_bytes - how long will a string be after conversion?
+ * @ucs - pointer to input string
+ * @maxbytes - don't go past this many bytes of input string
+ * @codepage - destination codepage
+ *
+ * Walk a ucs2le string and return the number of bytes that the string will
+ * be after being converted to the given charset, not including any null
+ * termination required. Don't walk past maxbytes in the source buffer.
+ */
+int
+cifs_ucs2_bytes(const __le16 *from, int maxbytes,
+               const struct nls_table *codepage)
+{
+       int i;
+       int charlen, outlen = 0;
+       int maxwords = maxbytes / 2;
+       char tmp[NLS_MAX_CHARSET_SIZE];
+
+       for (i = 0; from[i] && i < maxwords; i++) {
+               charlen = codepage->uni2char(le16_to_cpu(from[i]), tmp,
+                                            NLS_MAX_CHARSET_SIZE);
+               if (charlen > 0)
+                       outlen += charlen;
+               else
+                       outlen++;
+       }
+
+       return outlen;
+}
+
 /*
  * cifs_mapchar - convert a little-endian char to proper char in codepage
  * @target - where converted character should be copied