NLS: update handling of Unicode
This patch (as1239) updates the kernel's treatment of Unicode. The
character-set conversion routines are well behind the current state of
the Unicode specification: They don't recognize the existence of code
points beyond plane 0 or of surrogate pairs in the UTF-16 encoding.
The old wchar_t 16-bit type is retained because it's still used in
lots of places. This shouldn't cause any new problems; if a
conversion now results in an invalid 16-bit code then before it must
have yielded an undefined code.
Difficult-to-read names like "utf_mbstowcs" are replaced with more
transparent names like "utf8s_to_utf16s" and the ordering of the
parameters is rationalized (buffer lengths come immediate after the
pointers they refer to, and the inputs precede the outputs).
Fortunately the low-level conversion routines are used in only a few
places; the interfaces to the higher-level uni2char and char2uni
methods have been left unchanged.
Signed-off-by: Alan Stern <stern@rowland.harvard.edu>
Acked-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
diff --git a/fs/fat/dir.c b/fs/fat/dir.c
index f350029..7c14c8c 100644
--- a/fs/fat/dir.c
+++ b/fs/fat/dir.c
@@ -22,6 +22,19 @@
#include <asm/uaccess.h>
#include "fat.h"
+/*
+ * Maximum buffer size of short name.
+ * [(MSDOS_NAME + '.') * max one char + nul]
+ * For msdos style, ['.' (hidden) + MSDOS_NAME + '.' + nul]
+ */
+#define FAT_MAX_SHORT_SIZE ((MSDOS_NAME + 1) * NLS_MAX_CHARSET_SIZE + 1)
+/*
+ * Maximum buffer size of unicode chars from slots.
+ * [(max longname slots * 13 (size in a slot) + nul) * sizeof(wchar_t)]
+ */
+#define FAT_MAX_UNI_CHARS ((MSDOS_SLOTS - 1) * 13 + 1)
+#define FAT_MAX_UNI_SIZE (FAT_MAX_UNI_CHARS * sizeof(wchar_t))
+
static inline loff_t fat_make_i_pos(struct super_block *sb,
struct buffer_head *bh,
struct msdos_dir_entry *de)
@@ -171,7 +184,8 @@
unsigned char *buf, int size)
{
if (sbi->options.utf8)
- return utf8_wcstombs(buf, uni, size);
+ return utf16s_to_utf8s(uni, FAT_MAX_UNI_CHARS,
+ UTF16_HOST_ENDIAN, buf, size);
else
return uni16_to_x8(buf, uni, size, sbi->options.unicode_xlate,
sbi->nls_io);
@@ -325,19 +339,6 @@
}
/*
- * Maximum buffer size of short name.
- * [(MSDOS_NAME + '.') * max one char + nul]
- * For msdos style, ['.' (hidden) + MSDOS_NAME + '.' + nul]
- */
-#define FAT_MAX_SHORT_SIZE ((MSDOS_NAME + 1) * NLS_MAX_CHARSET_SIZE + 1)
-/*
- * Maximum buffer size of unicode chars from slots.
- * [(max longname slots * 13 (size in a slot) + nul) * sizeof(wchar_t)]
- */
-#define FAT_MAX_UNI_CHARS ((MSDOS_SLOTS - 1) * 13 + 1)
-#define FAT_MAX_UNI_SIZE (FAT_MAX_UNI_CHARS * sizeof(wchar_t))
-
-/*
* Return values: negative -> error, 0 -> not found, positive -> found,
* value is the total amount of slots, including the shortname entry.
*/