[PATCH] hfs: NLS support

This adds NLS support to HFS.  Using the kernel options iocharset and codepage
it's possible to map the disk encoding to a local mapping.  If these options
are not used, it falls back to the old direct mapping.

Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 96 insertions, 20 deletions

diff --git a/fs/hfs/trans.c b/fs/hfs/trans.c
index fb9720abbadd..e673a88b8ae7 100644
--- a/fs/hfs/trans.c
+++ b/fs/hfs/trans.c
@@ -9,12 +9,15 @@
  * with ':' vs. '/' as the path-element separator.
  */
 
+#include <linux/types.h>
+#include <linux/nls.h>
+
 #include "hfs_fs.h"
 
 /*================ Global functions ================*/
 
 /*
- * hfs_mac2triv()
+ * hfs_mac2asc()
  *
  * Given a 'Pascal String' (a string preceded by a length byte) in
  * the Macintosh character set produce the corresponding filename using
@@ -27,23 +30,58 @@
  * by ':' which never appears in HFS filenames.  All other characters
  * are passed unchanged from input to output.
  */
-int hfs_mac2triv(char *out, const struct hfs_name *in)
+int hfs_mac2asc(struct super_block *sb, char *out, const struct hfs_name *in)
 {
-        const char *p;
-        char c;
-        int i, len;
+        struct nls_table *nls_disk = HFS_SB(sb)->nls_disk;
+        struct nls_table *nls_io = HFS_SB(sb)->nls_io;
+        const char *src;
+        char *dst;
+        int srclen, dstlen, size;
+
+        src = in->name;
+        srclen = in->len;
+        dst = out;
+        dstlen = HFS_MAX_NAMELEN;
+        if (nls_io) {
+                wchar_t ch;
 
-        len = in->len;
-        p = in->name;
-        for (i = 0; i < len; i++) {
-                c = *p++;
-                *out++ = c == '/' ? ':' : c;
+                while (srclen > 0) {
+                        if (nls_disk) {
+                                size = nls_disk->char2uni(src, srclen, &ch);
+                                if (size <= 0) {
+                                        ch = '?';
+                                        size = 1;
+                                }
+                                src += size;
+                                srclen -= size;
+                        } else {
+                                ch = *src++;
+                                srclen--;
+                        }
+                        if (ch == '/')
+                                ch = ':';
+                        size = nls_io->uni2char(ch, dst, dstlen);
+                        if (size < 0) {
+                                if (size == -ENAMETOOLONG)
+                                        goto out;
+                                *dst = '?';
+                                size = 1;
+                        }
+                        dst += size;
+                        dstlen -= size;
+                }
+        } else {
+                char ch;
+
+                while (--srclen >= 0)
+                        *dst++ = (ch = *src++) == '/' ? ':' : ch;
         }
-        return i;
+out:
+        return dst - out;
 }
 
 /*
- * hfs_triv2mac()
+ * hfs_asc2mac()
  *
  * Given an ASCII string (not null-terminated) and its length,
  * generate the corresponding filename in the Macintosh character set
@@ -54,19 +92,57 @@ int hfs_mac2triv(char *out, const struct hfs_name *in)
  * This routine is a inverse to hfs_mac2triv().
  * A ':' is replaced by a '/'.
  */
-void hfs_triv2mac(struct hfs_name *out, struct qstr *in)
+void hfs_asc2mac(struct super_block *sb, struct hfs_name *out, struct qstr *in)
 {
+        struct nls_table *nls_disk = HFS_SB(sb)->nls_disk;
+        struct nls_table *nls_io = HFS_SB(sb)->nls_io;
         const char *src;
-        char *dst, c;
-        int i, len;
+        char *dst;
+        int srclen, dstlen, size;
 
-        out->len = len = min((unsigned int)HFS_NAMELEN, in->len);
         src = in->name;
+        srclen = in->len;
         dst = out->name;
-        for (i = 0; i < len; i++) {
-                c = *src++;
-                *dst++ = c == ':' ? '/' : c;
+        dstlen = HFS_NAMELEN;
+        if (nls_io) {
+                wchar_t ch;
+
+                while (srclen > 0) {
+                        size = nls_io->char2uni(src, srclen, &ch);
+                        if (size < 0) {
+                                ch = '?';
+                                size = 1;
+                        }
+                        src += size;
+                        srclen -= size;
+                        if (ch == ':')
+                                ch = '/';
+                        if (nls_disk) {
+                                size = nls_disk->uni2char(ch, dst, dstlen);
+                                if (size < 0) {
+                                        if (size == -ENAMETOOLONG)
+                                                goto out;
+                                        *dst = '?';
+                                        size = 1;
+                                }
+                                dst += size;
+                                dstlen -= size;
+                        } else {
+                                *dst++ = ch > 0xff ? '?' : ch;
+                                dstlen--;
+                        }
+                }
+        } else {
+                char ch;
+
+                if (dstlen > srclen)
+                        dstlen = srclen;
+                while (--dstlen >= 0)
+                        *dst++ = (ch = *src++) == ':' ? '/' : ch;
         }
-        for (; i < HFS_NAMELEN; i++)
+out:
+        out->len = dst - (char *)out->name;
+        dstlen = HFS_NAMELEN - out->len;
+        while (--dstlen >= 0)
                 *dst++ = 0;
 }