ascmagic.c revision 175296
1/*
2 * Copyright (c) Ian F. Darwin 1986-1995.
3 * Software written by Ian F. Darwin and others;
4 * maintained 1995-present by Christos Zoulas and others.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice immediately at the beginning of the file, without modification,
11 *    this list of conditions, and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
20 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28/*
29 * ASCII magic -- file types that we know based on keywords
30 * that can appear anywhere in the file.
31 *
32 * Extensively modified by Eric Fischer <enf@pobox.com> in July, 2000,
33 * to handle character codes other than ASCII on a unified basis.
34 *
35 * Joerg Wunsch <joerg@freebsd.org> wrote the original support for 8-bit
36 * international characters, now subsumed into this file.
37 */
38
39#include "file.h"
40#include "magic.h"
41#include <stdio.h>
42#include <string.h>
43#include <memory.h>
44#include <ctype.h>
45#include <stdlib.h>
46#ifdef HAVE_UNISTD_H
47#include <unistd.h>
48#endif
49#include "names.h"
50
51#ifndef	lint
52FILE_RCSID("@(#)$File: ascmagic.c,v 1.53 2007/10/29 00:54:08 christos Exp $")
53#endif	/* lint */
54
55typedef unsigned long unichar;
56
57#define MAXLINELEN 300	/* longest sane line length */
58#define ISSPC(x) ((x) == ' ' || (x) == '\t' || (x) == '\r' || (x) == '\n' \
59		  || (x) == 0x85 || (x) == '\f')
60
61private int looks_ascii(const unsigned char *, size_t, unichar *, size_t *);
62private int looks_utf8(const unsigned char *, size_t, unichar *, size_t *);
63private int looks_unicode(const unsigned char *, size_t, unichar *, size_t *);
64private int looks_latin1(const unsigned char *, size_t, unichar *, size_t *);
65private int looks_extended(const unsigned char *, size_t, unichar *, size_t *);
66private void from_ebcdic(const unsigned char *, size_t, unsigned char *);
67private int ascmatch(const unsigned char *, const unichar *, size_t);
68
69
70protected int
71file_ascmagic(struct magic_set *ms, const unsigned char *buf, size_t nbytes)
72{
73	size_t i;
74	unsigned char *nbuf = NULL;
75	unichar *ubuf = NULL;
76	size_t ulen;
77	struct names *p;
78	int rv = -1;
79	int mime = ms->flags & MAGIC_MIME;
80
81	const char *code = NULL;
82	const char *code_mime = NULL;
83	const char *type = NULL;
84	const char *subtype = NULL;
85	const char *subtype_mime = NULL;
86
87	int has_escapes = 0;
88	int has_backspace = 0;
89	int seen_cr = 0;
90
91	int n_crlf = 0;
92	int n_lf = 0;
93	int n_cr = 0;
94	int n_nel = 0;
95
96	size_t last_line_end = (size_t)-1;
97	int has_long_lines = 0;
98
99	/*
100	 * Undo the NUL-termination kindly provided by process()
101	 * but leave at least one byte to look at
102	 */
103	while (nbytes > 1 && buf[nbytes - 1] == '\0')
104		nbytes--;
105
106	if ((nbuf = calloc(1, (nbytes + 1) * sizeof(nbuf[0]))) == NULL)
107		goto done;
108	if ((ubuf = calloc(1, (nbytes + 1) * sizeof(ubuf[0]))) == NULL)
109		goto done;
110
111	/*
112	 * Then try to determine whether it's any character code we can
113	 * identify.  Each of these tests, if it succeeds, will leave
114	 * the text converted into one-unichar-per-character Unicode in
115	 * ubuf, and the number of characters converted in ulen.
116	 */
117	if (looks_ascii(buf, nbytes, ubuf, &ulen)) {
118		code = "ASCII";
119		code_mime = "us-ascii";
120		type = "text";
121	} else if (looks_utf8(buf, nbytes, ubuf, &ulen)) {
122		code = "UTF-8 Unicode";
123		code_mime = "utf-8";
124		type = "text";
125	} else if ((i = looks_unicode(buf, nbytes, ubuf, &ulen)) != 0) {
126		if (i == 1)
127			code = "Little-endian UTF-16 Unicode";
128		else
129			code = "Big-endian UTF-16 Unicode";
130
131		type = "character data";
132		code_mime = "utf-16";    /* is this defined? */
133	} else if (looks_latin1(buf, nbytes, ubuf, &ulen)) {
134		code = "ISO-8859";
135		type = "text";
136		code_mime = "iso-8859-1";
137	} else if (looks_extended(buf, nbytes, ubuf, &ulen)) {
138		code = "Non-ISO extended-ASCII";
139		type = "text";
140		code_mime = "unknown";
141	} else {
142		from_ebcdic(buf, nbytes, nbuf);
143
144		if (looks_ascii(nbuf, nbytes, ubuf, &ulen)) {
145			code = "EBCDIC";
146			type = "character data";
147			code_mime = "ebcdic";
148		} else if (looks_latin1(nbuf, nbytes, ubuf, &ulen)) {
149			code = "International EBCDIC";
150			type = "character data";
151			code_mime = "ebcdic";
152		} else {
153			rv = 0;
154			goto done;  /* doesn't look like text at all */
155		}
156	}
157
158	if (nbytes <= 1) {
159		rv = 0;
160		goto done;
161	}
162
163	/*
164	 * for troff, look for . + letter + letter or .\";
165	 * this must be done to disambiguate tar archives' ./file
166	 * and other trash from real troff input.
167	 *
168	 * I believe Plan 9 troff allows non-ASCII characters in the names
169	 * of macros, so this test might possibly fail on such a file.
170	 */
171	if ((ms->flags & MAGIC_NO_CHECK_TROFF) == 0 && *ubuf == '.') {
172		unichar *tp = ubuf + 1;
173
174		while (ISSPC(*tp))
175			++tp;	/* skip leading whitespace */
176		if ((tp[0] == '\\' && tp[1] == '\"') ||
177		    (isascii((unsigned char)tp[0]) &&
178		     isalnum((unsigned char)tp[0]) &&
179		     isascii((unsigned char)tp[1]) &&
180		     isalnum((unsigned char)tp[1]) &&
181		     ISSPC(tp[2]))) {
182			subtype_mime = "text/troff";
183			subtype = "troff or preprocessor input";
184			goto subtype_identified;
185		}
186	}
187
188	/* look for tokens from names.h - this is expensive! */
189
190	if ((ms->flags & MAGIC_NO_CHECK_TOKENS) != 0)
191		goto subtype_identified;
192
193	i = 0;
194	while (i < ulen) {
195		size_t end;
196
197		/*
198		 * skip past any leading space
199		 */
200		while (i < ulen && ISSPC(ubuf[i]))
201			i++;
202		if (i >= ulen)
203			break;
204
205		/*
206		 * find the next whitespace
207		 */
208		for (end = i + 1; end < nbytes; end++)
209			if (ISSPC(ubuf[end]))
210				break;
211
212		/*
213		 * compare the word thus isolated against the token list
214		 */
215		for (p = names; p < names + NNAMES; p++) {
216			if (ascmatch((const unsigned char *)p->name, ubuf + i,
217			    end - i)) {
218				subtype = types[p->type].human;
219				subtype_mime = types[p->type].mime;
220				goto subtype_identified;
221			}
222		}
223
224		i = end;
225	}
226
227subtype_identified:
228
229	/*
230	 * Now try to discover other details about the file.
231	 */
232	for (i = 0; i < ulen; i++) {
233		if (ubuf[i] == '\n') {
234			if (seen_cr)
235				n_crlf++;
236			else
237				n_lf++;
238			last_line_end = i;
239		} else if (seen_cr)
240			n_cr++;
241
242		seen_cr = (ubuf[i] == '\r');
243		if (seen_cr)
244			last_line_end = i;
245
246		if (ubuf[i] == 0x85) { /* X3.64/ECMA-43 "next line" character */
247			n_nel++;
248			last_line_end = i;
249		}
250
251		/* If this line is _longer_ than MAXLINELEN, remember it. */
252		if (i > last_line_end + MAXLINELEN)
253			has_long_lines = 1;
254
255		if (ubuf[i] == '\033')
256			has_escapes = 1;
257		if (ubuf[i] == '\b')
258			has_backspace = 1;
259	}
260
261	/* Beware, if the data has been truncated, the final CR could have
262	   been followed by a LF.  If we have HOWMANY bytes, it indicates
263	   that the data might have been truncated, probably even before
264	   this function was called. */
265	if (seen_cr && nbytes < HOWMANY)
266		n_cr++;
267
268	if (mime) {
269		if (mime & MAGIC_MIME_TYPE) {
270			if (subtype_mime) {
271				if (file_printf(ms, subtype_mime) == -1)
272					goto done;
273			} else {
274				if (file_printf(ms, "text/plain") == -1)
275					goto done;
276			}
277		}
278
279		if ((mime == 0 || mime == MAGIC_MIME) && code_mime) {
280			if ((mime & MAGIC_MIME_TYPE) &&
281			    file_printf(ms, " charset=") == -1)
282				goto done;
283			if (file_printf(ms, code_mime) == -1)
284				goto done;
285		}
286
287		if (mime == MAGIC_MIME_ENCODING)
288			file_printf(ms, "binary");
289	} else {
290		if (file_printf(ms, code) == -1)
291			goto done;
292
293		if (subtype) {
294			if (file_printf(ms, " ") == -1)
295				goto done;
296			if (file_printf(ms, subtype) == -1)
297				goto done;
298		}
299
300		if (file_printf(ms, " ") == -1)
301			goto done;
302		if (file_printf(ms, type) == -1)
303			goto done;
304
305		if (has_long_lines)
306			if (file_printf(ms, ", with very long lines") == -1)
307				goto done;
308
309		/*
310		 * Only report line terminators if we find one other than LF,
311		 * or if we find none at all.
312		 */
313		if ((n_crlf == 0 && n_cr == 0 && n_nel == 0 && n_lf == 0) ||
314		    (n_crlf != 0 || n_cr != 0 || n_nel != 0)) {
315			if (file_printf(ms, ", with") == -1)
316				goto done;
317
318			if (n_crlf == 0 && n_cr == 0 && n_nel == 0 && n_lf == 0)			{
319				if (file_printf(ms, " no") == -1)
320					goto done;
321			} else {
322				if (n_crlf) {
323					if (file_printf(ms, " CRLF") == -1)
324						goto done;
325					if (n_cr || n_lf || n_nel)
326						if (file_printf(ms, ",") == -1)
327							goto done;
328				}
329				if (n_cr) {
330					if (file_printf(ms, " CR") == -1)
331						goto done;
332					if (n_lf || n_nel)
333						if (file_printf(ms, ",") == -1)
334							goto done;
335				}
336				if (n_lf) {
337					if (file_printf(ms, " LF") == -1)
338						goto done;
339					if (n_nel)
340						if (file_printf(ms, ",") == -1)
341							goto done;
342				}
343				if (n_nel)
344					if (file_printf(ms, " NEL") == -1)
345						goto done;
346			}
347
348			if (file_printf(ms, " line terminators") == -1)
349				goto done;
350		}
351
352		if (has_escapes)
353			if (file_printf(ms, ", with escape sequences") == -1)
354				goto done;
355		if (has_backspace)
356			if (file_printf(ms, ", with overstriking") == -1)
357				goto done;
358	}
359	rv = 1;
360done:
361	if (nbuf)
362		free(nbuf);
363	if (ubuf)
364		free(ubuf);
365
366	return rv;
367}
368
369private int
370ascmatch(const unsigned char *s, const unichar *us, size_t ulen)
371{
372	size_t i;
373
374	for (i = 0; i < ulen; i++) {
375		if (s[i] != us[i])
376			return 0;
377	}
378
379	if (s[i])
380		return 0;
381	else
382		return 1;
383}
384
385/*
386 * This table reflects a particular philosophy about what constitutes
387 * "text," and there is room for disagreement about it.
388 *
389 * Version 3.31 of the file command considered a file to be ASCII if
390 * each of its characters was approved by either the isascii() or
391 * isalpha() function.  On most systems, this would mean that any
392 * file consisting only of characters in the range 0x00 ... 0x7F
393 * would be called ASCII text, but many systems might reasonably
394 * consider some characters outside this range to be alphabetic,
395 * so the file command would call such characters ASCII.  It might
396 * have been more accurate to call this "considered textual on the
397 * local system" than "ASCII."
398 *
399 * It considered a file to be "International language text" if each
400 * of its characters was either an ASCII printing character (according
401 * to the real ASCII standard, not the above test), a character in
402 * the range 0x80 ... 0xFF, or one of the following control characters:
403 * backspace, tab, line feed, vertical tab, form feed, carriage return,
404 * escape.  No attempt was made to determine the language in which files
405 * of this type were written.
406 *
407 *
408 * The table below considers a file to be ASCII if all of its characters
409 * are either ASCII printing characters (again, according to the X3.4
410 * standard, not isascii()) or any of the following controls: bell,
411 * backspace, tab, line feed, form feed, carriage return, esc, nextline.
412 *
413 * I include bell because some programs (particularly shell scripts)
414 * use it literally, even though it is rare in normal text.  I exclude
415 * vertical tab because it never seems to be used in real text.  I also
416 * include, with hesitation, the X3.64/ECMA-43 control nextline (0x85),
417 * because that's what the dd EBCDIC->ASCII table maps the EBCDIC newline
418 * character to.  It might be more appropriate to include it in the 8859
419 * set instead of the ASCII set, but it's got to be included in *something*
420 * we recognize or EBCDIC files aren't going to be considered textual.
421 * Some old Unix source files use SO/SI (^N/^O) to shift between Greek
422 * and Latin characters, so these should possibly be allowed.  But they
423 * make a real mess on VT100-style displays if they're not paired properly,
424 * so we are probably better off not calling them text.
425 *
426 * A file is considered to be ISO-8859 text if its characters are all
427 * either ASCII, according to the above definition, or printing characters
428 * from the ISO-8859 8-bit extension, characters 0xA0 ... 0xFF.
429 *
430 * Finally, a file is considered to be international text from some other
431 * character code if its characters are all either ISO-8859 (according to
432 * the above definition) or characters in the range 0x80 ... 0x9F, which
433 * ISO-8859 considers to be control characters but the IBM PC and Macintosh
434 * consider to be printing characters.
435 */
436
437#define F 0   /* character never appears in text */
438#define T 1   /* character appears in plain ASCII text */
439#define I 2   /* character appears in ISO-8859 text */
440#define X 3   /* character appears in non-ISO extended ASCII (Mac, IBM PC) */
441
442private char text_chars[256] = {
443	/*                  BEL BS HT LF    FF CR    */
444	F, F, F, F, F, F, F, T, T, T, T, F, T, T, F, F,  /* 0x0X */
445        /*                              ESC          */
446	F, F, F, F, F, F, F, F, F, F, F, T, F, F, F, F,  /* 0x1X */
447	T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T,  /* 0x2X */
448	T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T,  /* 0x3X */
449	T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T,  /* 0x4X */
450	T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T,  /* 0x5X */
451	T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T,  /* 0x6X */
452	T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, F,  /* 0x7X */
453	/*            NEL                            */
454	X, X, X, X, X, T, X, X, X, X, X, X, X, X, X, X,  /* 0x8X */
455	X, X, X, X, X, X, X, X, X, X, X, X, X, X, X, X,  /* 0x9X */
456	I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I,  /* 0xaX */
457	I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I,  /* 0xbX */
458	I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I,  /* 0xcX */
459	I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I,  /* 0xdX */
460	I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I,  /* 0xeX */
461	I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I   /* 0xfX */
462};
463
464private int
465looks_ascii(const unsigned char *buf, size_t nbytes, unichar *ubuf,
466    size_t *ulen)
467{
468	size_t i;
469
470	*ulen = 0;
471
472	for (i = 0; i < nbytes; i++) {
473		int t = text_chars[buf[i]];
474
475		if (t != T)
476			return 0;
477
478		ubuf[(*ulen)++] = buf[i];
479	}
480
481	return 1;
482}
483
484private int
485looks_latin1(const unsigned char *buf, size_t nbytes, unichar *ubuf, size_t *ulen)
486{
487	size_t i;
488
489	*ulen = 0;
490
491	for (i = 0; i < nbytes; i++) {
492		int t = text_chars[buf[i]];
493
494		if (t != T && t != I)
495			return 0;
496
497		ubuf[(*ulen)++] = buf[i];
498	}
499
500	return 1;
501}
502
503private int
504looks_extended(const unsigned char *buf, size_t nbytes, unichar *ubuf,
505    size_t *ulen)
506{
507	size_t i;
508
509	*ulen = 0;
510
511	for (i = 0; i < nbytes; i++) {
512		int t = text_chars[buf[i]];
513
514		if (t != T && t != I && t != X)
515			return 0;
516
517		ubuf[(*ulen)++] = buf[i];
518	}
519
520	return 1;
521}
522
523private int
524looks_utf8(const unsigned char *buf, size_t nbytes, unichar *ubuf, size_t *ulen)
525{
526	size_t i;
527	int n;
528	unichar c;
529	int gotone = 0;
530
531	*ulen = 0;
532
533	for (i = 0; i < nbytes; i++) {
534		if ((buf[i] & 0x80) == 0) {	   /* 0xxxxxxx is plain ASCII */
535			/*
536			 * Even if the whole file is valid UTF-8 sequences,
537			 * still reject it if it uses weird control characters.
538			 */
539
540			if (text_chars[buf[i]] != T)
541				return 0;
542
543			ubuf[(*ulen)++] = buf[i];
544		} else if ((buf[i] & 0x40) == 0) { /* 10xxxxxx never 1st byte */
545			return 0;
546		} else {			   /* 11xxxxxx begins UTF-8 */
547			int following;
548
549			if ((buf[i] & 0x20) == 0) {		/* 110xxxxx */
550				c = buf[i] & 0x1f;
551				following = 1;
552			} else if ((buf[i] & 0x10) == 0) {	/* 1110xxxx */
553				c = buf[i] & 0x0f;
554				following = 2;
555			} else if ((buf[i] & 0x08) == 0) {	/* 11110xxx */
556				c = buf[i] & 0x07;
557				following = 3;
558			} else if ((buf[i] & 0x04) == 0) {	/* 111110xx */
559				c = buf[i] & 0x03;
560				following = 4;
561			} else if ((buf[i] & 0x02) == 0) {	/* 1111110x */
562				c = buf[i] & 0x01;
563				following = 5;
564			} else
565				return 0;
566
567			for (n = 0; n < following; n++) {
568				i++;
569				if (i >= nbytes)
570					goto done;
571
572				if ((buf[i] & 0x80) == 0 || (buf[i] & 0x40))
573					return 0;
574
575				c = (c << 6) + (buf[i] & 0x3f);
576			}
577
578			ubuf[(*ulen)++] = c;
579			gotone = 1;
580		}
581	}
582done:
583	return gotone;   /* don't claim it's UTF-8 if it's all 7-bit */
584}
585
586private int
587looks_unicode(const unsigned char *buf, size_t nbytes, unichar *ubuf,
588    size_t *ulen)
589{
590	int bigend;
591	size_t i;
592
593	if (nbytes < 2)
594		return 0;
595
596	if (buf[0] == 0xff && buf[1] == 0xfe)
597		bigend = 0;
598	else if (buf[0] == 0xfe && buf[1] == 0xff)
599		bigend = 1;
600	else
601		return 0;
602
603	*ulen = 0;
604
605	for (i = 2; i + 1 < nbytes; i += 2) {
606		/* XXX fix to properly handle chars > 65536 */
607
608		if (bigend)
609			ubuf[(*ulen)++] = buf[i + 1] + 256 * buf[i];
610		else
611			ubuf[(*ulen)++] = buf[i] + 256 * buf[i + 1];
612
613		if (ubuf[*ulen - 1] == 0xfffe)
614			return 0;
615		if (ubuf[*ulen - 1] < 128 &&
616		    text_chars[(size_t)ubuf[*ulen - 1]] != T)
617			return 0;
618	}
619
620	return 1 + bigend;
621}
622
623#undef F
624#undef T
625#undef I
626#undef X
627
628/*
629 * This table maps each EBCDIC character to an (8-bit extended) ASCII
630 * character, as specified in the rationale for the dd(1) command in
631 * draft 11.2 (September, 1991) of the POSIX P1003.2 standard.
632 *
633 * Unfortunately it does not seem to correspond exactly to any of the
634 * five variants of EBCDIC documented in IBM's _Enterprise Systems
635 * Architecture/390: Principles of Operation_, SA22-7201-06, Seventh
636 * Edition, July, 1999, pp. I-1 - I-4.
637 *
638 * Fortunately, though, all versions of EBCDIC, including this one, agree
639 * on most of the printing characters that also appear in (7-bit) ASCII.
640 * Of these, only '|', '!', '~', '^', '[', and ']' are in question at all.
641 *
642 * Fortunately too, there is general agreement that codes 0x00 through
643 * 0x3F represent control characters, 0x41 a nonbreaking space, and the
644 * remainder printing characters.
645 *
646 * This is sufficient to allow us to identify EBCDIC text and to distinguish
647 * between old-style and internationalized examples of text.
648 */
649
650private unsigned char ebcdic_to_ascii[] = {
651  0,   1,   2,   3, 156,   9, 134, 127, 151, 141, 142,  11,  12,  13,  14,  15,
652 16,  17,  18,  19, 157, 133,   8, 135,  24,  25, 146, 143,  28,  29,  30,  31,
653128, 129, 130, 131, 132,  10,  23,  27, 136, 137, 138, 139, 140,   5,   6,   7,
654144, 145,  22, 147, 148, 149, 150,   4, 152, 153, 154, 155,  20,  21, 158,  26,
655' ', 160, 161, 162, 163, 164, 165, 166, 167, 168, 213, '.', '<', '(', '+', '|',
656'&', 169, 170, 171, 172, 173, 174, 175, 176, 177, '!', '$', '*', ')', ';', '~',
657'-', '/', 178, 179, 180, 181, 182, 183, 184, 185, 203, ',', '%', '_', '>', '?',
658186, 187, 188, 189, 190, 191, 192, 193, 194, '`', ':', '#', '@', '\'','=', '"',
659195, 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 196, 197, 198, 199, 200, 201,
660202, 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', '^', 204, 205, 206, 207, 208,
661209, 229, 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 210, 211, 212, '[', 214, 215,
662216, 217, 218, 219, 220, 221, 222, 223, 224, 225, 226, 227, 228, ']', 230, 231,
663'{', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 232, 233, 234, 235, 236, 237,
664'}', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 238, 239, 240, 241, 242, 243,
665'\\',159, 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 244, 245, 246, 247, 248, 249,
666'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 250, 251, 252, 253, 254, 255
667};
668
669#ifdef notdef
670/*
671 * The following EBCDIC-to-ASCII table may relate more closely to reality,
672 * or at least to modern reality.  It comes from
673 *
674 *   http://ftp.s390.ibm.com/products/oe/bpxqp9.html
675 *
676 * and maps the characters of EBCDIC code page 1047 (the code used for
677 * Unix-derived software on IBM's 390 systems) to the corresponding
678 * characters from ISO 8859-1.
679 *
680 * If this table is used instead of the above one, some of the special
681 * cases for the NEL character can be taken out of the code.
682 */
683
684private unsigned char ebcdic_1047_to_8859[] = {
6850x00,0x01,0x02,0x03,0x9C,0x09,0x86,0x7F,0x97,0x8D,0x8E,0x0B,0x0C,0x0D,0x0E,0x0F,
6860x10,0x11,0x12,0x13,0x9D,0x0A,0x08,0x87,0x18,0x19,0x92,0x8F,0x1C,0x1D,0x1E,0x1F,
6870x80,0x81,0x82,0x83,0x84,0x85,0x17,0x1B,0x88,0x89,0x8A,0x8B,0x8C,0x05,0x06,0x07,
6880x90,0x91,0x16,0x93,0x94,0x95,0x96,0x04,0x98,0x99,0x9A,0x9B,0x14,0x15,0x9E,0x1A,
6890x20,0xA0,0xE2,0xE4,0xE0,0xE1,0xE3,0xE5,0xE7,0xF1,0xA2,0x2E,0x3C,0x28,0x2B,0x7C,
6900x26,0xE9,0xEA,0xEB,0xE8,0xED,0xEE,0xEF,0xEC,0xDF,0x21,0x24,0x2A,0x29,0x3B,0x5E,
6910x2D,0x2F,0xC2,0xC4,0xC0,0xC1,0xC3,0xC5,0xC7,0xD1,0xA6,0x2C,0x25,0x5F,0x3E,0x3F,
6920xF8,0xC9,0xCA,0xCB,0xC8,0xCD,0xCE,0xCF,0xCC,0x60,0x3A,0x23,0x40,0x27,0x3D,0x22,
6930xD8,0x61,0x62,0x63,0x64,0x65,0x66,0x67,0x68,0x69,0xAB,0xBB,0xF0,0xFD,0xFE,0xB1,
6940xB0,0x6A,0x6B,0x6C,0x6D,0x6E,0x6F,0x70,0x71,0x72,0xAA,0xBA,0xE6,0xB8,0xC6,0xA4,
6950xB5,0x7E,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7A,0xA1,0xBF,0xD0,0x5B,0xDE,0xAE,
6960xAC,0xA3,0xA5,0xB7,0xA9,0xA7,0xB6,0xBC,0xBD,0xBE,0xDD,0xA8,0xAF,0x5D,0xB4,0xD7,
6970x7B,0x41,0x42,0x43,0x44,0x45,0x46,0x47,0x48,0x49,0xAD,0xF4,0xF6,0xF2,0xF3,0xF5,
6980x7D,0x4A,0x4B,0x4C,0x4D,0x4E,0x4F,0x50,0x51,0x52,0xB9,0xFB,0xFC,0xF9,0xFA,0xFF,
6990x5C,0xF7,0x53,0x54,0x55,0x56,0x57,0x58,0x59,0x5A,0xB2,0xD4,0xD6,0xD2,0xD3,0xD5,
7000x30,0x31,0x32,0x33,0x34,0x35,0x36,0x37,0x38,0x39,0xB3,0xDB,0xDC,0xD9,0xDA,0x9F
701};
702#endif
703
704/*
705 * Copy buf[0 ... nbytes-1] into out[], translating EBCDIC to ASCII.
706 */
707private void
708from_ebcdic(const unsigned char *buf, size_t nbytes, unsigned char *out)
709{
710	size_t i;
711
712	for (i = 0; i < nbytes; i++) {
713		out[i] = ebcdic_to_ascii[buf[i]];
714	}
715}
716