source: vendor/3.5.0/source3/lib/iconv.c

Last change on this file was 414, checked in by Herwig Bauernfeind, 15 years ago

Samba 3.5.0: Initial import
File size: 17.0 KB
Line 
1/*
2 Unix SMB/CIFS implementation.
3 minimal iconv implementation
4 Copyright (C) Andrew Tridgell 2001
5 Copyright (C) Jelmer Vernooij 2002,2003
6
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
11
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>.
19*/
20
21#include "includes.h"
22
23/*
24 * We have to use strcasecmp here as the character conversions
25 * haven't been initialised yet. JRA.
26 */
27
28#undef strcasecmp
29
30/**
31 * @file
32 *
33 * @brief Samba wrapper/stub for iconv character set conversion.
34 *
35 * iconv is the XPG2 interface for converting between character
36 * encodings. This file provides a Samba wrapper around it, and also
37 * a simple reimplementation that is used if the system does not
38 * implement iconv.
39 *
40 * Samba only works with encodings that are supersets of ASCII: ascii
41 * characters like whitespace can be tested for directly, multibyte
42 * sequences start with a byte with the high bit set, and strings are
43 * terminated by a nul byte.
44 *
45 * Note that the only function provided by iconv is conversion between
46 * characters. It doesn't directly support operations like
47 * uppercasing or comparison. We have to convert to UCS-2 and compare
48 * there.
49 *
50 * @sa Samba Developers Guide
51 **/
52
53static_decl_charset;
54
55static size_t ascii_pull(void *,const char **, size_t *, char **, size_t *);
56static size_t ascii_push(void *,const char **, size_t *, char **, size_t *);
57static size_t latin1_push(void *,const char **, size_t *, char **, size_t *);
58static size_t utf8_pull(void *,const char **, size_t *, char **, size_t *);
59static size_t utf8_push(void *,const char **, size_t *, char **, size_t *);
60static size_t ucs2hex_pull(void *,const char **, size_t *, char **, size_t *);
61static size_t ucs2hex_push(void *,const char **, size_t *, char **, size_t *);
62static size_t iconv_copy(void *,const char **, size_t *, char **, size_t *);
63static size_t iconv_swab (void *,const char **, size_t *, char **, size_t *);
64
65static struct charset_functions builtin_functions[] = {
66 /* windows is really neither UCS-2 not UTF-16 */
67 {"UCS-2LE", iconv_copy, iconv_copy},
68 {"UTF-16LE", iconv_copy, iconv_copy},
69 {"UCS-2BE", iconv_swab, iconv_swab},
70 {"UTF-16BE", iconv_swab, iconv_swab},
71
72 /* we include the UTF-8 alias to cope with differing locale settings */
73 {"UTF8", utf8_pull, utf8_push},
74 {"UTF-8", utf8_pull, utf8_push},
75 {"ASCII", ascii_pull, ascii_push},
76 {"646", ascii_pull, ascii_push},
77 {"ISO-8859-1", ascii_pull, latin1_push},
78 {"UCS2-HEX", ucs2hex_pull, ucs2hex_push},
79 {NULL, NULL, NULL}
80};
81
82static struct charset_functions *charsets = NULL;
83
84static struct charset_functions *find_charset_functions(const char *name)
85{
86 struct charset_functions *c = charsets;
87
88 while(c) {
89 if (strcasecmp(name, c->name) == 0) {
90 return c;
91 }
92 c = c->next;
93 }
94
95 return NULL;
96}
97
98NTSTATUS smb_register_charset(struct charset_functions *funcs)
99{
100 if (!funcs) {
101 return NT_STATUS_INVALID_PARAMETER;
102 }
103
104 DEBUG(5, ("Attempting to register new charset %s\n", funcs->name));
105 /* Check whether we already have this charset... */
106 if (find_charset_functions(funcs->name)) {
107 DEBUG(0, ("Duplicate charset %s, not registering\n", funcs->name));
108 return NT_STATUS_OBJECT_NAME_COLLISION;
109 }
110
111 funcs->next = funcs->prev = NULL;
112 DEBUG(5, ("Registered charset %s\n", funcs->name));
113 DLIST_ADD(charsets, funcs);
114 return NT_STATUS_OK;
115}
116
117static void lazy_initialize_iconv(void)
118{
119 static bool initialized;
120 int i;
121
122 if (!initialized) {
123 initialized = True;
124 for(i = 0; builtin_functions[i].name; i++)
125 smb_register_charset(&builtin_functions[i]);
126 static_init_charset;
127 }
128}
129
130#ifdef HAVE_NATIVE_ICONV
131/* if there was an error then reset the internal state,
132 this ensures that we don't have a shift state remaining for
133 character sets like SJIS */
134static size_t sys_iconv(void *cd,
135 const char **inbuf, size_t *inbytesleft,
136 char **outbuf, size_t *outbytesleft)
137{
138 size_t ret = iconv((iconv_t)cd,
139 (void *)inbuf, inbytesleft,
140 outbuf, outbytesleft);
141 if (ret == (size_t)-1) {
142 int saved_errno = errno;
143 iconv(cd, NULL, NULL, NULL, NULL);
144 errno = saved_errno;
145 }
146 return ret;
147}
148#endif
149
150/**
151 * This is a simple portable iconv() implementaion.
152 *
153 * It only knows about a very small number of character sets - just
154 * enough that Samba works on systems that don't have iconv.
155 **/
156size_t smb_iconv(smb_iconv_t cd,
157 const char **inbuf, size_t *inbytesleft,
158 char **outbuf, size_t *outbytesleft)
159{
160 char cvtbuf[2048];
161 char *bufp = cvtbuf;
162 size_t bufsize;
163
164 /* in many cases we can go direct */
165 if (cd->direct) {
166 return cd->direct(cd->cd_direct,
167 inbuf, inbytesleft, outbuf, outbytesleft);
168 }
169
170
171 /* otherwise we have to do it chunks at a time */
172 while (*inbytesleft > 0) {
173 bufp = cvtbuf;
174 bufsize = sizeof(cvtbuf);
175
176 if (cd->pull(cd->cd_pull,
177 inbuf, inbytesleft, &bufp, &bufsize) == -1
178 && errno != E2BIG) return -1;
179
180 bufp = cvtbuf;
181 bufsize = sizeof(cvtbuf) - bufsize;
182
183 if (cd->push(cd->cd_push,
184 (const char **)&bufp, &bufsize,
185 outbuf, outbytesleft) == -1) return -1;
186 }
187
188 return 0;
189}
190
191
192static bool is_utf16(const char *name)
193{
194 return strcasecmp(name, "UCS-2LE") == 0 ||
195 strcasecmp(name, "UTF-16LE") == 0;
196}
197
198/*
199 simple iconv_open() wrapper
200 */
201smb_iconv_t smb_iconv_open(const char *tocode, const char *fromcode)
202{
203 smb_iconv_t ret;
204 struct charset_functions *from, *to;
205
206 lazy_initialize_iconv();
207 from = charsets;
208 to = charsets;
209
210 ret = SMB_MALLOC_P(struct smb_iconv_s);
211 if (!ret) {
212 errno = ENOMEM;
213 return (smb_iconv_t)-1;
214 }
215 memset(ret, 0, sizeof(struct smb_iconv_s));
216
217 ret->from_name = SMB_STRDUP(fromcode);
218 ret->to_name = SMB_STRDUP(tocode);
219
220 /* check for the simplest null conversion */
221 if (strcasecmp(fromcode, tocode) == 0) {
222 ret->direct = iconv_copy;
223 return ret;
224 }
225
226 /* check if we have a builtin function for this conversion */
227 from = find_charset_functions(fromcode);
228 if(from)ret->pull = from->pull;
229
230 to = find_charset_functions(tocode);
231 if(to)ret->push = to->push;
232
233 /* check if we can use iconv for this conversion */
234#ifdef HAVE_NATIVE_ICONV
235 if (!ret->pull) {
236 ret->cd_pull = iconv_open("UTF-16LE", fromcode);
237 if (ret->cd_pull == (iconv_t)-1)
238 ret->cd_pull = iconv_open("UCS-2LE", fromcode);
239 if (ret->cd_pull != (iconv_t)-1)
240 ret->pull = sys_iconv;
241 }
242
243 if (!ret->push) {
244 ret->cd_push = iconv_open(tocode, "UTF-16LE");
245 if (ret->cd_push == (iconv_t)-1)
246 ret->cd_push = iconv_open(tocode, "UCS-2LE");
247 if (ret->cd_push != (iconv_t)-1)
248 ret->push = sys_iconv;
249 }
250#endif
251
252 /* check if there is a module available that can do this conversion */
253 if (!ret->pull && NT_STATUS_IS_OK(smb_probe_module("charset", fromcode))) {
254 if(!(from = find_charset_functions(fromcode)))
255 DEBUG(0, ("Module %s doesn't provide charset %s!\n", fromcode, fromcode));
256 else
257 ret->pull = from->pull;
258 }
259
260 if (!ret->push && NT_STATUS_IS_OK(smb_probe_module("charset", tocode))) {
261 if(!(to = find_charset_functions(tocode)))
262 DEBUG(0, ("Module %s doesn't provide charset %s!\n", tocode, tocode));
263 else
264 ret->push = to->push;
265 }
266
267 if (!ret->push || !ret->pull) {
268 SAFE_FREE(ret->from_name);
269 SAFE_FREE(ret->to_name);
270 SAFE_FREE(ret);
271 errno = EINVAL;
272 return (smb_iconv_t)-1;
273 }
274
275 /* check for conversion to/from ucs2 */
276 if (is_utf16(fromcode) && to) {
277 ret->direct = to->push;
278 ret->push = ret->pull = NULL;
279 return ret;
280 }
281
282 if (is_utf16(tocode) && from) {
283 ret->direct = from->pull;
284 ret->push = ret->pull = NULL;
285 return ret;
286 }
287
288 /* Check if we can do the conversion direct */
289#ifdef HAVE_NATIVE_ICONV
290 if (is_utf16(fromcode)) {
291 ret->direct = sys_iconv;
292 ret->cd_direct = ret->cd_push;
293 ret->cd_push = NULL;
294 return ret;
295 }
296 if (is_utf16(tocode)) {
297 ret->direct = sys_iconv;
298 ret->cd_direct = ret->cd_pull;
299 ret->cd_pull = NULL;
300 return ret;
301 }
302#endif
303
304 return ret;
305}
306
307/*
308 simple iconv_close() wrapper
309*/
310int smb_iconv_close (smb_iconv_t cd)
311{
312#ifdef HAVE_NATIVE_ICONV
313 if (cd->cd_direct) iconv_close((iconv_t)cd->cd_direct);
314 if (cd->cd_pull) iconv_close((iconv_t)cd->cd_pull);
315 if (cd->cd_push) iconv_close((iconv_t)cd->cd_push);
316#endif
317
318 SAFE_FREE(cd->from_name);
319 SAFE_FREE(cd->to_name);
320
321 memset(cd, 0, sizeof(*cd));
322 SAFE_FREE(cd);
323 return 0;
324}
325
326
327/**********************************************************************
328 the following functions implement the builtin character sets in Samba
329 and also the "test" character sets that are designed to test
330 multi-byte character set support for english users
331***********************************************************************/
332
333static size_t ascii_pull(void *cd, const char **inbuf, size_t *inbytesleft,
334 char **outbuf, size_t *outbytesleft)
335{
336 while (*inbytesleft >= 1 && *outbytesleft >= 2) {
337 (*outbuf)[0] = (*inbuf)[0];
338 (*outbuf)[1] = 0;
339 (*inbytesleft) -= 1;
340 (*outbytesleft) -= 2;
341 (*inbuf) += 1;
342 (*outbuf) += 2;
343 }
344
345 if (*inbytesleft > 0) {
346 errno = E2BIG;
347 return -1;
348 }
349
350 return 0;
351}
352
353static size_t ascii_push(void *cd, const char **inbuf, size_t *inbytesleft,
354 char **outbuf, size_t *outbytesleft)
355{
356 int ir_count=0;
357
358 while (*inbytesleft >= 2 && *outbytesleft >= 1) {
359 (*outbuf)[0] = (*inbuf)[0] & 0x7F;
360 if ((*inbuf)[1]) ir_count++;
361 (*inbytesleft) -= 2;
362 (*outbytesleft) -= 1;
363 (*inbuf) += 2;
364 (*outbuf) += 1;
365 }
366
367 if (*inbytesleft == 1) {
368 errno = EINVAL;
369 return -1;
370 }
371
372 if (*inbytesleft > 1) {
373 errno = E2BIG;
374 return -1;
375 }
376
377 return ir_count;
378}
379
380static size_t latin1_push(void *cd, const char **inbuf, size_t *inbytesleft,
381 char **outbuf, size_t *outbytesleft)
382{
383 int ir_count=0;
384
385 while (*inbytesleft >= 2 && *outbytesleft >= 1) {
386 (*outbuf)[0] = (*inbuf)[0];
387 if ((*inbuf)[1]) ir_count++;
388 (*inbytesleft) -= 2;
389 (*outbytesleft) -= 1;
390 (*inbuf) += 2;
391 (*outbuf) += 1;
392 }
393
394 if (*inbytesleft == 1) {
395 errno = EINVAL;
396 return -1;
397 }
398
399 if (*inbytesleft > 1) {
400 errno = E2BIG;
401 return -1;
402 }
403
404 return ir_count;
405}
406
407static size_t ucs2hex_pull(void *cd, const char **inbuf, size_t *inbytesleft,
408 char **outbuf, size_t *outbytesleft)
409{
410 while (*inbytesleft >= 1 && *outbytesleft >= 2) {
411 unsigned v;
412
413 if ((*inbuf)[0] != '@') {
414 /* seven bit ascii case */
415 (*outbuf)[0] = (*inbuf)[0];
416 (*outbuf)[1] = 0;
417 (*inbytesleft) -= 1;
418 (*outbytesleft) -= 2;
419 (*inbuf) += 1;
420 (*outbuf) += 2;
421 continue;
422 }
423 /* it's a hex character */
424 if (*inbytesleft < 5) {
425 errno = EINVAL;
426 return -1;
427 }
428
429 if (sscanf(&(*inbuf)[1], "%04x", &v) != 1) {
430 errno = EILSEQ;
431 return -1;
432 }
433
434 (*outbuf)[0] = v&0xff;
435 (*outbuf)[1] = v>>8;
436 (*inbytesleft) -= 5;
437 (*outbytesleft) -= 2;
438 (*inbuf) += 5;
439 (*outbuf) += 2;
440 }
441
442 if (*inbytesleft > 0) {
443 errno = E2BIG;
444 return -1;
445 }
446
447 return 0;
448}
449
450static size_t ucs2hex_push(void *cd, const char **inbuf, size_t *inbytesleft,
451 char **outbuf, size_t *outbytesleft)
452{
453 while (*inbytesleft >= 2 && *outbytesleft >= 1) {
454 char buf[6];
455
456 if ((*inbuf)[1] == 0 &&
457 ((*inbuf)[0] & 0x80) == 0 &&
458 (*inbuf)[0] != '@') {
459 (*outbuf)[0] = (*inbuf)[0];
460 (*inbytesleft) -= 2;
461 (*outbytesleft) -= 1;
462 (*inbuf) += 2;
463 (*outbuf) += 1;
464 continue;
465 }
466 if (*outbytesleft < 5) {
467 errno = E2BIG;
468 return -1;
469 }
470 snprintf(buf, 6, "@%04x", SVAL(*inbuf, 0));
471 memcpy(*outbuf, buf, 5);
472 (*inbytesleft) -= 2;
473 (*outbytesleft) -= 5;
474 (*inbuf) += 2;
475 (*outbuf) += 5;
476 }
477
478 if (*inbytesleft == 1) {
479 errno = EINVAL;
480 return -1;
481 }
482
483 if (*inbytesleft > 1) {
484 errno = E2BIG;
485 return -1;
486 }
487
488 return 0;
489}
490
491static size_t iconv_swab(void *cd, const char **inbuf, size_t *inbytesleft,
492 char **outbuf, size_t *outbytesleft)
493{
494 int n;
495
496 n = MIN(*inbytesleft, *outbytesleft);
497
498 swab(*inbuf, *outbuf, (n&~1));
499 if (n&1) {
500 (*outbuf)[n-1] = 0;
501 }
502
503 (*inbytesleft) -= n;
504 (*outbytesleft) -= n;
505 (*inbuf) += n;
506 (*outbuf) += n;
507
508 if (*inbytesleft > 0) {
509 errno = E2BIG;
510 return -1;
511 }
512
513 return 0;
514}
515
516static size_t iconv_copy(void *cd, const char **inbuf, size_t *inbytesleft,
517 char **outbuf, size_t *outbytesleft)
518{
519 int n;
520
521 n = MIN(*inbytesleft, *outbytesleft);
522
523 memmove(*outbuf, *inbuf, n);
524
525 (*inbytesleft) -= n;
526 (*outbytesleft) -= n;
527 (*inbuf) += n;
528 (*outbuf) += n;
529
530 if (*inbytesleft > 0) {
531 errno = E2BIG;
532 return -1;
533 }
534
535 return 0;
536}
537
538static size_t utf8_pull(void *cd, const char **inbuf, size_t *inbytesleft,
539 char **outbuf, size_t *outbytesleft)
540{
541 size_t in_left=*inbytesleft, out_left=*outbytesleft;
542 const uint8 *c = (const uint8 *)*inbuf;
543 uint8 *uc = (uint8 *)*outbuf;
544
545 while (in_left >= 1 && out_left >= 2) {
546 unsigned int codepoint;
547
548 if ((c[0] & 0x80) == 0) {
549 uc[0] = c[0];
550 uc[1] = 0;
551 c += 1;
552 in_left -= 1;
553 out_left -= 2;
554 uc += 2;
555 continue;
556 }
557
558 if ((c[0] & 0xe0) == 0xc0) {
559 if (in_left < 2 ||
560 (c[1] & 0xc0) != 0x80) {
561 errno = EILSEQ;
562 goto error;
563 }
564 codepoint = (c[1]&0x3f) | ((c[0]&0x1f)<<6);
565 if (codepoint < 0x80) {
566 /* don't accept UTF-8 characters that are not minimally packed */
567 errno = EILSEQ;
568 goto error;
569 }
570 uc[1] = codepoint >> 8;
571 uc[0] = codepoint & 0xff;
572 c += 2;
573 in_left -= 2;
574 out_left -= 2;
575 uc += 2;
576 continue;
577 }
578
579 if ((c[0] & 0xf0) == 0xe0) {
580 if (in_left < 3 ||
581 (c[1] & 0xc0) != 0x80 ||
582 (c[2] & 0xc0) != 0x80) {
583 errno = EILSEQ;
584 goto error;
585 }
586 codepoint = (c[2]&0x3f) | ((c[1]&0x3f)<<6) | ((c[0]&0xf)<<12);
587 if (codepoint < 0x800) {
588 /* don't accept UTF-8 characters that are not minimally packed */
589 errno = EILSEQ;
590 goto error;
591 }
592 uc[1] = codepoint >> 8;
593 uc[0] = codepoint & 0xff;
594 c += 3;
595 in_left -= 3;
596 out_left -= 2;
597 uc += 2;
598 continue;
599 }
600
601 if ((c[0] & 0xf8) == 0xf0) {
602 if (in_left < 4 ||
603 (c[1] & 0xc0) != 0x80 ||
604 (c[2] & 0xc0) != 0x80 ||
605 (c[3] & 0xc0) != 0x80) {
606 errno = EILSEQ;
607 goto error;
608 }
609 codepoint =
610 (c[3]&0x3f) |
611 ((c[2]&0x3f)<<6) |
612 ((c[1]&0x3f)<<12) |
613 ((c[0]&0x7)<<18);
614 if (codepoint < 0x10000 || codepoint > 0x10ffff) {
615 /* don't accept UTF-8 characters that are not minimally packed */
616 errno = EILSEQ;
617 goto error;
618 }
619
620 codepoint -= 0x10000;
621
622 if (out_left < 4) {
623 errno = E2BIG;
624 goto error;
625 }
626
627 uc[0] = (codepoint>>10) & 0xFF;
628 uc[1] = (codepoint>>18) | 0xd8;
629 uc[2] = codepoint & 0xFF;
630 uc[3] = ((codepoint>>8) & 0x3) | 0xdc;
631 c += 4;
632 in_left -= 4;
633 out_left -= 4;
634 uc += 4;
635 continue;
636 }
637
638 /* we don't handle 5 byte sequences */
639 errno = EINVAL;
640 goto error;
641 }
642
643 if (in_left > 0) {
644 errno = E2BIG;
645 goto error;
646 }
647
648 *inbytesleft = in_left;
649 *outbytesleft = out_left;
650 *inbuf = (char *)c;
651 *outbuf = (char *)uc;
652 return 0;
653
654error:
655 *inbytesleft = in_left;
656 *outbytesleft = out_left;
657 *inbuf = (char *)c;
658 *outbuf = (char *)uc;
659 return -1;
660}
661
662static size_t utf8_push(void *cd, const char **inbuf, size_t *inbytesleft,
663 char **outbuf, size_t *outbytesleft)
664{
665 size_t in_left=*inbytesleft, out_left=*outbytesleft;
666 uint8 *c = (uint8 *)*outbuf;
667 const uint8 *uc = (const uint8 *)*inbuf;
668
669 while (in_left >= 2 && out_left >= 1) {
670 unsigned int codepoint;
671
672 if (uc[1] == 0 && !(uc[0] & 0x80)) {
673 /* simplest case */
674 c[0] = uc[0];
675 in_left -= 2;
676 out_left -= 1;
677 uc += 2;
678 c += 1;
679 continue;
680 }
681
682 if ((uc[1]&0xf8) == 0) {
683 /* next simplest case */
684 if (out_left < 2) {
685 errno = E2BIG;
686 goto error;
687 }
688 c[0] = 0xc0 | (uc[0]>>6) | (uc[1]<<2);
689 c[1] = 0x80 | (uc[0] & 0x3f);
690 in_left -= 2;
691 out_left -= 2;
692 uc += 2;
693 c += 2;
694 continue;
695 }
696
697 if ((uc[1] & 0xfc) == 0xdc) {
698 /* its the second part of a 4 byte sequence. Illegal */
699 if (in_left < 4) {
700 errno = EINVAL;
701 } else {
702 errno = EILSEQ;
703 }
704 goto error;
705 }
706
707 if ((uc[1] & 0xfc) != 0xd8) {
708 codepoint = uc[0] | (uc[1]<<8);
709 if (out_left < 3) {
710 errno = E2BIG;
711 goto error;
712 }
713 c[0] = 0xe0 | (codepoint >> 12);
714 c[1] = 0x80 | ((codepoint >> 6) & 0x3f);
715 c[2] = 0x80 | (codepoint & 0x3f);
716
717 in_left -= 2;
718 out_left -= 3;
719 uc += 2;
720 c += 3;
721 continue;
722 }
723
724 /* its the first part of a 4 byte sequence */
725 if (in_left < 4) {
726 errno = EINVAL;
727 goto error;
728 }
729 if ((uc[3] & 0xfc) != 0xdc) {
730 errno = EILSEQ;
731 goto error;
732 }
733 codepoint = 0x10000 + (uc[2] | ((uc[3] & 0x3)<<8) |
734 (uc[0]<<10) | ((uc[1] & 0x3)<<18));
735
736 if (out_left < 4) {
737 errno = E2BIG;
738 goto error;
739 }
740 c[0] = 0xf0 | (codepoint >> 18);
741 c[1] = 0x80 | ((codepoint >> 12) & 0x3f);
742 c[2] = 0x80 | ((codepoint >> 6) & 0x3f);
743 c[3] = 0x80 | (codepoint & 0x3f);
744
745 in_left -= 4;
746 out_left -= 4;
747 uc += 4;
748 c += 4;
749 }
750
751 if (in_left == 1) {
752 errno = EINVAL;
753 goto error;
754 }
755
756 if (in_left > 1) {
757 errno = E2BIG;
758 goto error;
759 }
760
761 *inbytesleft = in_left;
762 *outbytesleft = out_left;
763 *inbuf = (char *)uc;
764 *outbuf = (char *)c;
765
766 return 0;
767
768error:
769 *inbytesleft = in_left;
770 *outbytesleft = out_left;
771 *inbuf = (char *)uc;
772 *outbuf = (char *)c;
773 return -1;
774}
775
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