remove pointers to the defunct UDF mailing list
[linux-2.6.git] / fs / udf / unicode.c
1 /*
2  * unicode.c
3  *
4  * PURPOSE
5  *      Routines for converting between UTF-8 and OSTA Compressed Unicode.
6  *      Also handles filename mangling
7  *
8  * DESCRIPTION
9  *      OSTA Compressed Unicode is explained in the OSTA UDF specification.
10  *              http://www.osta.org/
11  *      UTF-8 is explained in the IETF RFC XXXX.
12  *              ftp://ftp.internic.net/rfc/rfcxxxx.txt
13  *
14  * COPYRIGHT
15  *      This file is distributed under the terms of the GNU General Public
16  *      License (GPL). Copies of the GPL can be obtained from:
17  *              ftp://prep.ai.mit.edu/pub/gnu/GPL
18  *      Each contributing author retains all rights to their own work.
19  */
20
21 #include "udfdecl.h"
22
23 #include <linux/kernel.h>
24 #include <linux/string.h>       /* for memset */
25 #include <linux/nls.h>
26 #include <linux/udf_fs.h>
27
28 #include "udf_sb.h"
29
30 static int udf_translate_to_linux(uint8_t *, uint8_t *, int, uint8_t *, int);
31
32 static int udf_char_to_ustr(struct ustr *dest, const uint8_t *src, int strlen)
33 {
34         if ( (!dest) || (!src) || (!strlen) || (strlen > UDF_NAME_LEN-2) )
35                 return 0;
36         memset(dest, 0, sizeof(struct ustr));
37         memcpy(dest->u_name, src, strlen);
38         dest->u_cmpID = 0x08;
39         dest->u_len = strlen;
40         return strlen;
41 }
42
43 /*
44  * udf_build_ustr
45  */
46 int udf_build_ustr(struct ustr *dest, dstring *ptr, int size)
47 {
48         int usesize;
49
50         if ( (!dest) || (!ptr) || (!size) )
51                 return -1;
52
53         memset(dest, 0, sizeof(struct ustr));
54         usesize= (size > UDF_NAME_LEN) ? UDF_NAME_LEN : size;
55         dest->u_cmpID=ptr[0];
56         dest->u_len=ptr[size-1];
57         memcpy(dest->u_name, ptr+1, usesize-1);
58         return 0;
59 }
60
61 /*
62  * udf_build_ustr_exact
63  */
64 static int udf_build_ustr_exact(struct ustr *dest, dstring *ptr, int exactsize)
65 {
66         if ( (!dest) || (!ptr) || (!exactsize) )
67                 return -1;
68
69         memset(dest, 0, sizeof(struct ustr));
70         dest->u_cmpID=ptr[0];
71         dest->u_len=exactsize-1;
72         memcpy(dest->u_name, ptr+1, exactsize-1);
73         return 0;
74 }
75
76 /*
77  * udf_ocu_to_utf8
78  *
79  * PURPOSE
80  *      Convert OSTA Compressed Unicode to the UTF-8 equivalent.
81  *
82  * DESCRIPTION
83  *      This routine is only called by udf_filldir().
84  *
85  * PRE-CONDITIONS
86  *      utf                     Pointer to UTF-8 output buffer.
87  *      ocu                     Pointer to OSTA Compressed Unicode input buffer
88  *                              of size UDF_NAME_LEN bytes.
89  *                              both of type "struct ustr *"
90  *
91  * POST-CONDITIONS
92  *      <return>                Zero on success.
93  *
94  * HISTORY
95  *      November 12, 1997 - Andrew E. Mileski
96  *      Written, tested, and released.
97  */
98 int udf_CS0toUTF8(struct ustr *utf_o, struct ustr *ocu_i)
99 {
100         uint8_t *ocu;
101         uint32_t c;
102         uint8_t cmp_id, ocu_len;
103         int i;
104
105         ocu = ocu_i->u_name;
106
107         ocu_len = ocu_i->u_len;
108         cmp_id = ocu_i->u_cmpID;
109         utf_o->u_len = 0;
110
111         if (ocu_len == 0)
112         {
113                 memset(utf_o, 0, sizeof(struct ustr));
114                 utf_o->u_cmpID = 0;
115                 utf_o->u_len = 0;
116                 return 0;
117         }
118
119         if ((cmp_id != 8) && (cmp_id != 16))
120         {
121                 printk(KERN_ERR "udf: unknown compression code (%d) stri=%s\n", cmp_id, ocu_i->u_name);
122                 return 0;
123         }
124
125         for (i = 0; (i < ocu_len) && (utf_o->u_len <= (UDF_NAME_LEN-3)) ;)
126         {
127
128                 /* Expand OSTA compressed Unicode to Unicode */
129                 c = ocu[i++];
130                 if (cmp_id == 16)
131                         c = (c << 8) | ocu[i++];
132
133                 /* Compress Unicode to UTF-8 */
134                 if (c < 0x80U)
135                         utf_o->u_name[utf_o->u_len++] = (uint8_t)c;
136                 else if (c < 0x800U)
137                 {
138                         utf_o->u_name[utf_o->u_len++] = (uint8_t)(0xc0 | (c >> 6));
139                         utf_o->u_name[utf_o->u_len++] = (uint8_t)(0x80 | (c & 0x3f));
140                 }
141                 else
142                 {
143                         utf_o->u_name[utf_o->u_len++] = (uint8_t)(0xe0 | (c >> 12));
144                         utf_o->u_name[utf_o->u_len++] = (uint8_t)(0x80 | ((c >> 6) & 0x3f));
145                         utf_o->u_name[utf_o->u_len++] = (uint8_t)(0x80 | (c & 0x3f));
146                 }
147         }
148         utf_o->u_cmpID=8;
149
150         return utf_o->u_len;
151 }
152
153 /*
154  *
155  * udf_utf8_to_ocu
156  *
157  * PURPOSE
158  *      Convert UTF-8 to the OSTA Compressed Unicode equivalent.
159  *
160  * DESCRIPTION
161  *      This routine is only called by udf_lookup().
162  *
163  * PRE-CONDITIONS
164  *      ocu                     Pointer to OSTA Compressed Unicode output
165  *                              buffer of size UDF_NAME_LEN bytes.
166  *      utf                     Pointer to UTF-8 input buffer.
167  *      utf_len                 Length of UTF-8 input buffer in bytes.
168  *
169  * POST-CONDITIONS
170  *      <return>                Zero on success.
171  *
172  * HISTORY
173  *      November 12, 1997 - Andrew E. Mileski
174  *      Written, tested, and released.
175  */
176 static int udf_UTF8toCS0(dstring *ocu, struct ustr *utf, int length)
177 {
178         unsigned c, i, max_val, utf_char;
179         int utf_cnt, u_len;
180
181         memset(ocu, 0, sizeof(dstring) * length);
182         ocu[0] = 8;
183         max_val = 0xffU;
184
185 try_again:
186         u_len = 0U;
187         utf_char = 0U;
188         utf_cnt = 0U;
189         for (i = 0U; i < utf->u_len; i++)
190         {
191                 c = (uint8_t)utf->u_name[i];
192
193                 /* Complete a multi-byte UTF-8 character */
194                 if (utf_cnt)
195                 {
196                         utf_char = (utf_char << 6) | (c & 0x3fU);
197                         if (--utf_cnt)
198                                 continue;
199                 }
200                 else
201                 {
202                         /* Check for a multi-byte UTF-8 character */
203                         if (c & 0x80U)
204                         {
205                                 /* Start a multi-byte UTF-8 character */
206                                 if ((c & 0xe0U) == 0xc0U)
207                                 {
208                                         utf_char = c & 0x1fU;
209                                         utf_cnt = 1;
210                                 }
211                                 else if ((c & 0xf0U) == 0xe0U)
212                                 {
213                                         utf_char = c & 0x0fU;
214                                         utf_cnt = 2;
215                                 }
216                                 else if ((c & 0xf8U) == 0xf0U)
217                                 {
218                                         utf_char = c & 0x07U;
219                                         utf_cnt = 3;
220                                 }
221                                 else if ((c & 0xfcU) == 0xf8U)
222                                 {
223                                         utf_char = c & 0x03U;
224                                         utf_cnt = 4;
225                                 }
226                                 else if ((c & 0xfeU) == 0xfcU)
227                                 {
228                                         utf_char = c & 0x01U;
229                                         utf_cnt = 5;
230                                 }
231                                 else
232                                         goto error_out;
233                                 continue;
234                         } else
235                                 /* Single byte UTF-8 character (most common) */
236                                 utf_char = c;
237                 }
238
239                 /* Choose no compression if necessary */
240                 if (utf_char > max_val)
241                 {
242                         if ( 0xffU == max_val )
243                         {
244                                 max_val = 0xffffU;
245                                 ocu[0] = (uint8_t)0x10U;
246                                 goto try_again;
247                         }
248                         goto error_out;
249                 }
250
251                 if (max_val == 0xffffU)
252                 {
253                         ocu[++u_len] = (uint8_t)(utf_char >> 8);
254                 }
255                 ocu[++u_len] = (uint8_t)(utf_char & 0xffU);
256         }
257
258
259         if (utf_cnt)
260         {
261 error_out:
262                 ocu[++u_len] = '?';
263                 printk(KERN_DEBUG "udf: bad UTF-8 character\n");
264         }
265
266         ocu[length - 1] = (uint8_t)u_len + 1;
267         return u_len + 1;
268 }
269
270 static int udf_CS0toNLS(struct nls_table *nls, struct ustr *utf_o, struct ustr *ocu_i)
271 {
272         uint8_t *ocu;
273         uint32_t c;
274         uint8_t cmp_id, ocu_len;
275         int i;
276
277         ocu = ocu_i->u_name;
278
279         ocu_len = ocu_i->u_len;
280         cmp_id = ocu_i->u_cmpID;
281         utf_o->u_len = 0;
282
283         if (ocu_len == 0)
284         {
285                 memset(utf_o, 0, sizeof(struct ustr));
286                 utf_o->u_cmpID = 0;
287                 utf_o->u_len = 0;
288                 return 0;
289         }
290
291         if ((cmp_id != 8) && (cmp_id != 16))
292         {
293                 printk(KERN_ERR "udf: unknown compression code (%d) stri=%s\n", cmp_id, ocu_i->u_name);
294                 return 0;
295         }
296
297         for (i = 0; (i < ocu_len) && (utf_o->u_len <= (UDF_NAME_LEN-3)) ;)
298         {
299                 /* Expand OSTA compressed Unicode to Unicode */
300                 c = ocu[i++];
301                 if (cmp_id == 16)
302                         c = (c << 8) | ocu[i++];
303
304                 utf_o->u_len += nls->uni2char(c, &utf_o->u_name[utf_o->u_len], 
305                         UDF_NAME_LEN - utf_o->u_len);
306         }
307         utf_o->u_cmpID=8;
308
309         return utf_o->u_len;
310 }
311
312 static int udf_NLStoCS0(struct nls_table *nls, dstring *ocu, struct ustr *uni, int length)
313 {
314         unsigned len, i, max_val;
315         uint16_t uni_char;
316         int u_len;
317
318         memset(ocu, 0, sizeof(dstring) * length);
319         ocu[0] = 8;
320         max_val = 0xffU;
321
322 try_again:
323         u_len = 0U;
324         for (i = 0U; i < uni->u_len; i++)
325         {
326                 len = nls->char2uni(&uni->u_name[i], uni->u_len-i, &uni_char);
327                 if (len <= 0)
328                         continue;
329
330                 if (uni_char > max_val)
331                 {
332                         max_val = 0xffffU;
333                         ocu[0] = (uint8_t)0x10U;
334                         goto try_again;
335                 }
336                 
337                 if (max_val == 0xffffU)
338                         ocu[++u_len] = (uint8_t)(uni_char >> 8);
339                 ocu[++u_len] = (uint8_t)(uni_char & 0xffU);
340                 i += len - 1;
341         }
342
343         ocu[length - 1] = (uint8_t)u_len + 1;
344         return u_len + 1;
345 }
346
347 int udf_get_filename(struct super_block *sb, uint8_t *sname, uint8_t *dname, int flen)
348 {
349         struct ustr filename, unifilename;
350         int len;
351
352         if (udf_build_ustr_exact(&unifilename, sname, flen))
353         {
354                 return 0;
355         }
356
357         if (UDF_QUERY_FLAG(sb, UDF_FLAG_UTF8))
358         {
359                 if (!udf_CS0toUTF8(&filename, &unifilename) )
360                 {
361                         udf_debug("Failed in udf_get_filename: sname = %s\n", sname);
362                         return 0;
363                 }
364         }
365         else if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP))
366         {
367                 if (!udf_CS0toNLS(UDF_SB(sb)->s_nls_map, &filename, &unifilename) )
368                 {
369                         udf_debug("Failed in udf_get_filename: sname = %s\n", sname);
370                         return 0;
371                 }
372         }
373         else
374                 return 0;
375
376         if ((len = udf_translate_to_linux(dname, filename.u_name, filename.u_len,
377                 unifilename.u_name, unifilename.u_len)))
378         {
379                 return len;
380         }
381         return 0;
382 }
383
384 int udf_put_filename(struct super_block *sb, const uint8_t *sname, uint8_t *dname, int flen)
385 {
386         struct ustr unifilename;
387         int namelen;
388
389         if ( !(udf_char_to_ustr(&unifilename, sname, flen)) )
390         {
391                 return 0;
392         }
393
394         if (UDF_QUERY_FLAG(sb, UDF_FLAG_UTF8))
395         {
396                 if ( !(namelen = udf_UTF8toCS0(dname, &unifilename, UDF_NAME_LEN)) )
397                 {
398                         return 0;
399                 }
400         }
401         else if (UDF_QUERY_FLAG(sb, UDF_FLAG_NLS_MAP))
402         {
403                 if ( !(namelen = udf_NLStoCS0(UDF_SB(sb)->s_nls_map, dname, &unifilename, UDF_NAME_LEN)) )
404                 {
405                         return 0;
406                 }
407         }
408         else
409                 return 0;
410
411         return namelen;
412 }
413
414 #define ILLEGAL_CHAR_MARK       '_'
415 #define EXT_MARK                        '.'
416 #define CRC_MARK                        '#'
417 #define EXT_SIZE                        5
418
419 static int udf_translate_to_linux(uint8_t *newName, uint8_t *udfName, int udfLen, uint8_t *fidName, int fidNameLen)
420 {
421         int index, newIndex = 0, needsCRC = 0;  
422         int extIndex = 0, newExtIndex = 0, hasExt = 0;
423         unsigned short valueCRC;
424         uint8_t curr;
425         const uint8_t hexChar[] = "0123456789ABCDEF";
426
427         if (udfName[0] == '.' && (udfLen == 1 ||
428                 (udfLen == 2 && udfName[1] == '.')))
429         {
430                 needsCRC = 1;
431                 newIndex = udfLen;
432                 memcpy(newName, udfName, udfLen);
433         }
434         else
435         {       
436                 for (index = 0; index < udfLen; index++)
437                 {
438                         curr = udfName[index];
439                         if (curr == '/' || curr == 0)
440                         {
441                                 needsCRC = 1;
442                                 curr = ILLEGAL_CHAR_MARK;
443                                 while (index+1 < udfLen && (udfName[index+1] == '/' ||
444                                         udfName[index+1] == 0))
445                                         index++;
446                         }
447                         if (curr == EXT_MARK && (udfLen - index - 1) <= EXT_SIZE)
448                         {
449                                 if (udfLen == index + 1)
450                                         hasExt = 0;
451                                 else
452                                 {
453                                         hasExt = 1;
454                                         extIndex = index;
455                                         newExtIndex = newIndex;
456                                 }
457                         }
458                         if (newIndex < 256)
459                                 newName[newIndex++] = curr;
460                         else
461                                 needsCRC = 1;
462                 }
463         }
464         if (needsCRC)
465         {
466                 uint8_t ext[EXT_SIZE];
467                 int localExtIndex = 0;
468
469                 if (hasExt)
470                 {
471                         int maxFilenameLen;
472                         for(index = 0; index<EXT_SIZE && extIndex + index +1 < udfLen;
473                                 index++ )
474                         {
475                                 curr = udfName[extIndex + index + 1];
476
477                                 if (curr == '/' || curr == 0)
478                                 {
479                                         needsCRC = 1;
480                                         curr = ILLEGAL_CHAR_MARK;
481                                         while(extIndex + index + 2 < udfLen && (index + 1 < EXT_SIZE
482                                                 && (udfName[extIndex + index + 2] == '/' ||
483                                                         udfName[extIndex + index + 2] == 0)))
484                                                 index++;
485                                 }
486                                 ext[localExtIndex++] = curr;
487                         }
488                         maxFilenameLen = 250 - localExtIndex;
489                         if (newIndex > maxFilenameLen)
490                                 newIndex = maxFilenameLen;
491                         else
492                                 newIndex = newExtIndex;
493                 }
494                 else if (newIndex > 250)
495                         newIndex = 250;
496                 newName[newIndex++] = CRC_MARK;
497                 valueCRC = udf_crc(fidName, fidNameLen, 0);
498                 newName[newIndex++] = hexChar[(valueCRC & 0xf000) >> 12];
499                 newName[newIndex++] = hexChar[(valueCRC & 0x0f00) >> 8];
500                 newName[newIndex++] = hexChar[(valueCRC & 0x00f0) >> 4];
501                 newName[newIndex++] = hexChar[(valueCRC & 0x000f)];
502
503                 if (hasExt)
504                 {
505                         newName[newIndex++] = EXT_MARK;
506                         for (index = 0;index < localExtIndex ;index++ )
507                                 newName[newIndex++] = ext[index];
508                 }
509         }
510         return newIndex;
511 }