ascmagic.c 21 KB

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  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. #include "file.h"
  39. #include "magic.h"
  40. #include <stdio.h>
  41. #include <string.h>
  42. #include <memory.h>
  43. #include <ctype.h>
  44. #include <stdlib.h>
  45. #ifdef HAVE_UNISTD_H
  46. #include <unistd.h>
  47. #endif
  48. #include "names.h"
  49. #ifndef lint
  50. FILE_RCSID("@(#)$File: ascmagic.c,v 1.50 2007/03/15 14:51:00 christos Exp $")
  51. #endif /* lint */
  52. typedef unsigned long unichar;
  53. #define MAXLINELEN 300 /* longest sane line length */
  54. #define ISSPC(x) ((x) == ' ' || (x) == '\t' || (x) == '\r' || (x) == '\n' \
  55. || (x) == 0x85 || (x) == '\f')
  56. private int looks_ascii(const unsigned char *, size_t, unichar *, size_t *);
  57. private int looks_utf8(const unsigned char *, size_t, unichar *, size_t *);
  58. private int looks_unicode(const unsigned char *, size_t, unichar *, size_t *);
  59. private int looks_latin1(const unsigned char *, size_t, unichar *, size_t *);
  60. private int looks_extended(const unsigned char *, size_t, unichar *, size_t *);
  61. private void from_ebcdic(const unsigned char *, size_t, unsigned char *);
  62. private int ascmatch(const unsigned char *, const unichar *, size_t);
  63. protected int
  64. file_ascmagic(struct magic_set *ms, const unsigned char *buf, size_t nbytes)
  65. {
  66. size_t i;
  67. unsigned char *nbuf = NULL;
  68. unichar *ubuf = NULL;
  69. size_t ulen;
  70. struct names *p;
  71. int rv = -1;
  72. const char *code = NULL;
  73. const char *code_mime = NULL;
  74. const char *type = NULL;
  75. const char *subtype = NULL;
  76. const char *subtype_mime = NULL;
  77. int has_escapes = 0;
  78. int has_backspace = 0;
  79. int seen_cr = 0;
  80. int n_crlf = 0;
  81. int n_lf = 0;
  82. int n_cr = 0;
  83. int n_nel = 0;
  84. size_t last_line_end = (size_t)-1;
  85. int has_long_lines = 0;
  86. /*
  87. * Undo the NUL-termination kindly provided by process()
  88. * but leave at least one byte to look at
  89. */
  90. while (nbytes > 1 && buf[nbytes - 1] == '\0')
  91. nbytes--;
  92. if ((nbuf = calloc(1, (nbytes + 1) * sizeof(nbuf[0]))) == NULL)
  93. goto done;
  94. if ((ubuf = calloc(1, (nbytes + 1) * sizeof(ubuf[0]))) == NULL)
  95. goto done;
  96. /*
  97. * Then try to determine whether it's any character code we can
  98. * identify. Each of these tests, if it succeeds, will leave
  99. * the text converted into one-unichar-per-character Unicode in
  100. * ubuf, and the number of characters converted in ulen.
  101. */
  102. if (looks_ascii(buf, nbytes, ubuf, &ulen)) {
  103. code = "ASCII";
  104. code_mime = "us-ascii";
  105. type = "text";
  106. } else if (looks_utf8(buf, nbytes, ubuf, &ulen)) {
  107. code = "UTF-8 Unicode";
  108. code_mime = "utf-8";
  109. type = "text";
  110. } else if ((i = looks_unicode(buf, nbytes, ubuf, &ulen)) != 0) {
  111. if (i == 1)
  112. code = "Little-endian UTF-16 Unicode";
  113. else
  114. code = "Big-endian UTF-16 Unicode";
  115. type = "character data";
  116. code_mime = "utf-16"; /* is this defined? */
  117. } else if (looks_latin1(buf, nbytes, ubuf, &ulen)) {
  118. code = "ISO-8859";
  119. type = "text";
  120. code_mime = "iso-8859-1";
  121. } else if (looks_extended(buf, nbytes, ubuf, &ulen)) {
  122. code = "Non-ISO extended-ASCII";
  123. type = "text";
  124. code_mime = "unknown";
  125. } else {
  126. from_ebcdic(buf, nbytes, nbuf);
  127. if (looks_ascii(nbuf, nbytes, ubuf, &ulen)) {
  128. code = "EBCDIC";
  129. type = "character data";
  130. code_mime = "ebcdic";
  131. } else if (looks_latin1(nbuf, nbytes, ubuf, &ulen)) {
  132. code = "International EBCDIC";
  133. type = "character data";
  134. code_mime = "ebcdic";
  135. } else {
  136. rv = 0;
  137. goto done; /* doesn't look like text at all */
  138. }
  139. }
  140. if (nbytes <= 1) {
  141. rv = 0;
  142. goto done;
  143. }
  144. /*
  145. * for troff, look for . + letter + letter or .\";
  146. * this must be done to disambiguate tar archives' ./file
  147. * and other trash from real troff input.
  148. *
  149. * I believe Plan 9 troff allows non-ASCII characters in the names
  150. * of macros, so this test might possibly fail on such a file.
  151. */
  152. if ((ms->flags & MAGIC_NO_CHECK_TROFF) == 0 && *ubuf == '.') {
  153. unichar *tp = ubuf + 1;
  154. while (ISSPC(*tp))
  155. ++tp; /* skip leading whitespace */
  156. if ((tp[0] == '\\' && tp[1] == '\"') ||
  157. (isascii((unsigned char)tp[0]) &&
  158. isalnum((unsigned char)tp[0]) &&
  159. isascii((unsigned char)tp[1]) &&
  160. isalnum((unsigned char)tp[1]) &&
  161. ISSPC(tp[2]))) {
  162. subtype_mime = "text/troff";
  163. subtype = "troff or preprocessor input";
  164. goto subtype_identified;
  165. }
  166. }
  167. if ((ms->flags & MAGIC_NO_CHECK_FORTRAN) == 0 &&
  168. (*buf == 'c' || *buf == 'C') && ISSPC(buf[1])) {
  169. subtype_mime = "text/fortran";
  170. subtype = "fortran program";
  171. goto subtype_identified;
  172. }
  173. /* look for tokens from names.h - this is expensive! */
  174. if ((ms->flags & MAGIC_NO_CHECK_TOKENS) != 0)
  175. goto subtype_identified;
  176. i = 0;
  177. while (i < ulen) {
  178. size_t end;
  179. /*
  180. * skip past any leading space
  181. */
  182. while (i < ulen && ISSPC(ubuf[i]))
  183. i++;
  184. if (i >= ulen)
  185. break;
  186. /*
  187. * find the next whitespace
  188. */
  189. for (end = i + 1; end < nbytes; end++)
  190. if (ISSPC(ubuf[end]))
  191. break;
  192. /*
  193. * compare the word thus isolated against the token list
  194. */
  195. for (p = names; p < names + NNAMES; p++) {
  196. if (ascmatch((const unsigned char *)p->name, ubuf + i,
  197. end - i)) {
  198. subtype = types[p->type].human;
  199. subtype_mime = types[p->type].mime;
  200. goto subtype_identified;
  201. }
  202. }
  203. i = end;
  204. }
  205. subtype_identified:
  206. /*
  207. * Now try to discover other details about the file.
  208. */
  209. for (i = 0; i < ulen; i++) {
  210. if (ubuf[i] == '\n') {
  211. if (seen_cr)
  212. n_crlf++;
  213. else
  214. n_lf++;
  215. last_line_end = i;
  216. } else if (seen_cr)
  217. n_cr++;
  218. seen_cr = (ubuf[i] == '\r');
  219. if (seen_cr)
  220. last_line_end = i;
  221. if (ubuf[i] == 0x85) { /* X3.64/ECMA-43 "next line" character */
  222. n_nel++;
  223. last_line_end = i;
  224. }
  225. /* If this line is _longer_ than MAXLINELEN, remember it. */
  226. if (i > last_line_end + MAXLINELEN)
  227. has_long_lines = 1;
  228. if (ubuf[i] == '\033')
  229. has_escapes = 1;
  230. if (ubuf[i] == '\b')
  231. has_backspace = 1;
  232. }
  233. /* Beware, if the data has been truncated, the final CR could have
  234. been followed by a LF. If we have HOWMANY bytes, it indicates
  235. that the data might have been truncated, probably even before
  236. this function was called. */
  237. if (seen_cr && nbytes < HOWMANY)
  238. n_cr++;
  239. if ((ms->flags & MAGIC_MIME)) {
  240. if (subtype_mime) {
  241. if (file_printf(ms, subtype_mime) == -1)
  242. goto done;
  243. } else {
  244. if (file_printf(ms, "text/plain") == -1)
  245. goto done;
  246. }
  247. if (code_mime) {
  248. if (file_printf(ms, "; charset=") == -1)
  249. goto done;
  250. if (file_printf(ms, code_mime) == -1)
  251. goto done;
  252. }
  253. } else {
  254. if (file_printf(ms, code) == -1)
  255. goto done;
  256. if (subtype) {
  257. if (file_printf(ms, " ") == -1)
  258. goto done;
  259. if (file_printf(ms, subtype) == -1)
  260. goto done;
  261. }
  262. if (file_printf(ms, " ") == -1)
  263. goto done;
  264. if (file_printf(ms, type) == -1)
  265. goto done;
  266. if (has_long_lines)
  267. if (file_printf(ms, ", with very long lines") == -1)
  268. goto done;
  269. /*
  270. * Only report line terminators if we find one other than LF,
  271. * or if we find none at all.
  272. */
  273. if ((n_crlf == 0 && n_cr == 0 && n_nel == 0 && n_lf == 0) ||
  274. (n_crlf != 0 || n_cr != 0 || n_nel != 0)) {
  275. if (file_printf(ms, ", with") == -1)
  276. goto done;
  277. if (n_crlf == 0 && n_cr == 0 && n_nel == 0 && n_lf == 0) {
  278. if (file_printf(ms, " no") == -1)
  279. goto done;
  280. } else {
  281. if (n_crlf) {
  282. if (file_printf(ms, " CRLF") == -1)
  283. goto done;
  284. if (n_cr || n_lf || n_nel)
  285. if (file_printf(ms, ",") == -1)
  286. goto done;
  287. }
  288. if (n_cr) {
  289. if (file_printf(ms, " CR") == -1)
  290. goto done;
  291. if (n_lf || n_nel)
  292. if (file_printf(ms, ",") == -1)
  293. goto done;
  294. }
  295. if (n_lf) {
  296. if (file_printf(ms, " LF") == -1)
  297. goto done;
  298. if (n_nel)
  299. if (file_printf(ms, ",") == -1)
  300. goto done;
  301. }
  302. if (n_nel)
  303. if (file_printf(ms, " NEL") == -1)
  304. goto done;
  305. }
  306. if (file_printf(ms, " line terminators") == -1)
  307. goto done;
  308. }
  309. if (has_escapes)
  310. if (file_printf(ms, ", with escape sequences") == -1)
  311. goto done;
  312. if (has_backspace)
  313. if (file_printf(ms, ", with overstriking") == -1)
  314. goto done;
  315. }
  316. rv = 1;
  317. done:
  318. if (nbuf)
  319. free(nbuf);
  320. if (ubuf)
  321. free(ubuf);
  322. return rv;
  323. }
  324. private int
  325. ascmatch(const unsigned char *s, const unichar *us, size_t ulen)
  326. {
  327. size_t i;
  328. for (i = 0; i < ulen; i++) {
  329. if (s[i] != us[i])
  330. return 0;
  331. }
  332. if (s[i])
  333. return 0;
  334. else
  335. return 1;
  336. }
  337. /*
  338. * This table reflects a particular philosophy about what constitutes
  339. * "text," and there is room for disagreement about it.
  340. *
  341. * Version 3.31 of the file command considered a file to be ASCII if
  342. * each of its characters was approved by either the isascii() or
  343. * isalpha() function. On most systems, this would mean that any
  344. * file consisting only of characters in the range 0x00 ... 0x7F
  345. * would be called ASCII text, but many systems might reasonably
  346. * consider some characters outside this range to be alphabetic,
  347. * so the file command would call such characters ASCII. It might
  348. * have been more accurate to call this "considered textual on the
  349. * local system" than "ASCII."
  350. *
  351. * It considered a file to be "International language text" if each
  352. * of its characters was either an ASCII printing character (according
  353. * to the real ASCII standard, not the above test), a character in
  354. * the range 0x80 ... 0xFF, or one of the following control characters:
  355. * backspace, tab, line feed, vertical tab, form feed, carriage return,
  356. * escape. No attempt was made to determine the language in which files
  357. * of this type were written.
  358. *
  359. *
  360. * The table below considers a file to be ASCII if all of its characters
  361. * are either ASCII printing characters (again, according to the X3.4
  362. * standard, not isascii()) or any of the following controls: bell,
  363. * backspace, tab, line feed, form feed, carriage return, esc, nextline.
  364. *
  365. * I include bell because some programs (particularly shell scripts)
  366. * use it literally, even though it is rare in normal text. I exclude
  367. * vertical tab because it never seems to be used in real text. I also
  368. * include, with hesitation, the X3.64/ECMA-43 control nextline (0x85),
  369. * because that's what the dd EBCDIC->ASCII table maps the EBCDIC newline
  370. * character to. It might be more appropriate to include it in the 8859
  371. * set instead of the ASCII set, but it's got to be included in *something*
  372. * we recognize or EBCDIC files aren't going to be considered textual.
  373. * Some old Unix source files use SO/SI (^N/^O) to shift between Greek
  374. * and Latin characters, so these should possibly be allowed. But they
  375. * make a real mess on VT100-style displays if they're not paired properly,
  376. * so we are probably better off not calling them text.
  377. *
  378. * A file is considered to be ISO-8859 text if its characters are all
  379. * either ASCII, according to the above definition, or printing characters
  380. * from the ISO-8859 8-bit extension, characters 0xA0 ... 0xFF.
  381. *
  382. * Finally, a file is considered to be international text from some other
  383. * character code if its characters are all either ISO-8859 (according to
  384. * the above definition) or characters in the range 0x80 ... 0x9F, which
  385. * ISO-8859 considers to be control characters but the IBM PC and Macintosh
  386. * consider to be printing characters.
  387. */
  388. #define F 0 /* character never appears in text */
  389. #define T 1 /* character appears in plain ASCII text */
  390. #define I 2 /* character appears in ISO-8859 text */
  391. #define X 3 /* character appears in non-ISO extended ASCII (Mac, IBM PC) */
  392. private char text_chars[256] = {
  393. /* BEL BS HT LF FF CR */
  394. F, F, F, F, F, F, F, T, T, T, T, F, T, T, F, F, /* 0x0X */
  395. /* ESC */
  396. F, F, F, F, F, F, F, F, F, F, F, T, F, F, F, F, /* 0x1X */
  397. T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, /* 0x2X */
  398. T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, /* 0x3X */
  399. T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, /* 0x4X */
  400. T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, /* 0x5X */
  401. T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, /* 0x6X */
  402. T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, F, /* 0x7X */
  403. /* NEL */
  404. X, X, X, X, X, T, X, X, X, X, X, X, X, X, X, X, /* 0x8X */
  405. X, X, X, X, X, X, X, X, X, X, X, X, X, X, X, X, /* 0x9X */
  406. I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, /* 0xaX */
  407. I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, /* 0xbX */
  408. I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, /* 0xcX */
  409. I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, /* 0xdX */
  410. I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, /* 0xeX */
  411. I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I /* 0xfX */
  412. };
  413. private int
  414. looks_ascii(const unsigned char *buf, size_t nbytes, unichar *ubuf,
  415. size_t *ulen)
  416. {
  417. size_t i;
  418. *ulen = 0;
  419. for (i = 0; i < nbytes; i++) {
  420. int t = text_chars[buf[i]];
  421. if (t != T)
  422. return 0;
  423. ubuf[(*ulen)++] = buf[i];
  424. }
  425. return 1;
  426. }
  427. private int
  428. looks_latin1(const unsigned char *buf, size_t nbytes, unichar *ubuf, size_t *ulen)
  429. {
  430. size_t i;
  431. *ulen = 0;
  432. for (i = 0; i < nbytes; i++) {
  433. int t = text_chars[buf[i]];
  434. if (t != T && t != I)
  435. return 0;
  436. ubuf[(*ulen)++] = buf[i];
  437. }
  438. return 1;
  439. }
  440. private int
  441. looks_extended(const unsigned char *buf, size_t nbytes, unichar *ubuf,
  442. size_t *ulen)
  443. {
  444. size_t i;
  445. *ulen = 0;
  446. for (i = 0; i < nbytes; i++) {
  447. int t = text_chars[buf[i]];
  448. if (t != T && t != I && t != X)
  449. return 0;
  450. ubuf[(*ulen)++] = buf[i];
  451. }
  452. return 1;
  453. }
  454. private int
  455. looks_utf8(const unsigned char *buf, size_t nbytes, unichar *ubuf, size_t *ulen)
  456. {
  457. size_t i;
  458. int n;
  459. unichar c;
  460. int gotone = 0;
  461. *ulen = 0;
  462. for (i = 0; i < nbytes; i++) {
  463. if ((buf[i] & 0x80) == 0) { /* 0xxxxxxx is plain ASCII */
  464. /*
  465. * Even if the whole file is valid UTF-8 sequences,
  466. * still reject it if it uses weird control characters.
  467. */
  468. if (text_chars[buf[i]] != T)
  469. return 0;
  470. ubuf[(*ulen)++] = buf[i];
  471. } else if ((buf[i] & 0x40) == 0) { /* 10xxxxxx never 1st byte */
  472. return 0;
  473. } else { /* 11xxxxxx begins UTF-8 */
  474. int following;
  475. if ((buf[i] & 0x20) == 0) { /* 110xxxxx */
  476. c = buf[i] & 0x1f;
  477. following = 1;
  478. } else if ((buf[i] & 0x10) == 0) { /* 1110xxxx */
  479. c = buf[i] & 0x0f;
  480. following = 2;
  481. } else if ((buf[i] & 0x08) == 0) { /* 11110xxx */
  482. c = buf[i] & 0x07;
  483. following = 3;
  484. } else if ((buf[i] & 0x04) == 0) { /* 111110xx */
  485. c = buf[i] & 0x03;
  486. following = 4;
  487. } else if ((buf[i] & 0x02) == 0) { /* 1111110x */
  488. c = buf[i] & 0x01;
  489. following = 5;
  490. } else
  491. return 0;
  492. for (n = 0; n < following; n++) {
  493. i++;
  494. if (i >= nbytes)
  495. goto done;
  496. if ((buf[i] & 0x80) == 0 || (buf[i] & 0x40))
  497. return 0;
  498. c = (c << 6) + (buf[i] & 0x3f);
  499. }
  500. ubuf[(*ulen)++] = c;
  501. gotone = 1;
  502. }
  503. }
  504. done:
  505. return gotone; /* don't claim it's UTF-8 if it's all 7-bit */
  506. }
  507. private int
  508. looks_unicode(const unsigned char *buf, size_t nbytes, unichar *ubuf,
  509. size_t *ulen)
  510. {
  511. int bigend;
  512. size_t i;
  513. if (nbytes < 2)
  514. return 0;
  515. if (buf[0] == 0xff && buf[1] == 0xfe)
  516. bigend = 0;
  517. else if (buf[0] == 0xfe && buf[1] == 0xff)
  518. bigend = 1;
  519. else
  520. return 0;
  521. *ulen = 0;
  522. for (i = 2; i + 1 < nbytes; i += 2) {
  523. /* XXX fix to properly handle chars > 65536 */
  524. if (bigend)
  525. ubuf[(*ulen)++] = buf[i + 1] + 256 * buf[i];
  526. else
  527. ubuf[(*ulen)++] = buf[i] + 256 * buf[i + 1];
  528. if (ubuf[*ulen - 1] == 0xfffe)
  529. return 0;
  530. if (ubuf[*ulen - 1] < 128 &&
  531. text_chars[(size_t)ubuf[*ulen - 1]] != T)
  532. return 0;
  533. }
  534. return 1 + bigend;
  535. }
  536. #undef F
  537. #undef T
  538. #undef I
  539. #undef X
  540. /*
  541. * This table maps each EBCDIC character to an (8-bit extended) ASCII
  542. * character, as specified in the rationale for the dd(1) command in
  543. * draft 11.2 (September, 1991) of the POSIX P1003.2 standard.
  544. *
  545. * Unfortunately it does not seem to correspond exactly to any of the
  546. * five variants of EBCDIC documented in IBM's _Enterprise Systems
  547. * Architecture/390: Principles of Operation_, SA22-7201-06, Seventh
  548. * Edition, July, 1999, pp. I-1 - I-4.
  549. *
  550. * Fortunately, though, all versions of EBCDIC, including this one, agree
  551. * on most of the printing characters that also appear in (7-bit) ASCII.
  552. * Of these, only '|', '!', '~', '^', '[', and ']' are in question at all.
  553. *
  554. * Fortunately too, there is general agreement that codes 0x00 through
  555. * 0x3F represent control characters, 0x41 a nonbreaking space, and the
  556. * remainder printing characters.
  557. *
  558. * This is sufficient to allow us to identify EBCDIC text and to distinguish
  559. * between old-style and internationalized examples of text.
  560. */
  561. private unsigned char ebcdic_to_ascii[] = {
  562. 0, 1, 2, 3, 156, 9, 134, 127, 151, 141, 142, 11, 12, 13, 14, 15,
  563. 16, 17, 18, 19, 157, 133, 8, 135, 24, 25, 146, 143, 28, 29, 30, 31,
  564. 128, 129, 130, 131, 132, 10, 23, 27, 136, 137, 138, 139, 140, 5, 6, 7,
  565. 144, 145, 22, 147, 148, 149, 150, 4, 152, 153, 154, 155, 20, 21, 158, 26,
  566. ' ', 160, 161, 162, 163, 164, 165, 166, 167, 168, 213, '.', '<', '(', '+', '|',
  567. '&', 169, 170, 171, 172, 173, 174, 175, 176, 177, '!', '$', '*', ')', ';', '~',
  568. '-', '/', 178, 179, 180, 181, 182, 183, 184, 185, 203, ',', '%', '_', '>', '?',
  569. 186, 187, 188, 189, 190, 191, 192, 193, 194, '`', ':', '#', '@', '\'','=', '"',
  570. 195, 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 196, 197, 198, 199, 200, 201,
  571. 202, 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', '^', 204, 205, 206, 207, 208,
  572. 209, 229, 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 210, 211, 212, '[', 214, 215,
  573. 216, 217, 218, 219, 220, 221, 222, 223, 224, 225, 226, 227, 228, ']', 230, 231,
  574. '{', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 232, 233, 234, 235, 236, 237,
  575. '}', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 238, 239, 240, 241, 242, 243,
  576. '\\',159, 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 244, 245, 246, 247, 248, 249,
  577. '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 250, 251, 252, 253, 254, 255
  578. };
  579. #ifdef notdef
  580. /*
  581. * The following EBCDIC-to-ASCII table may relate more closely to reality,
  582. * or at least to modern reality. It comes from
  583. *
  584. * http://ftp.s390.ibm.com/products/oe/bpxqp9.html
  585. *
  586. * and maps the characters of EBCDIC code page 1047 (the code used for
  587. * Unix-derived software on IBM's 390 systems) to the corresponding
  588. * characters from ISO 8859-1.
  589. *
  590. * If this table is used instead of the above one, some of the special
  591. * cases for the NEL character can be taken out of the code.
  592. */
  593. private unsigned char ebcdic_1047_to_8859[] = {
  594. 0x00,0x01,0x02,0x03,0x9C,0x09,0x86,0x7F,0x97,0x8D,0x8E,0x0B,0x0C,0x0D,0x0E,0x0F,
  595. 0x10,0x11,0x12,0x13,0x9D,0x0A,0x08,0x87,0x18,0x19,0x92,0x8F,0x1C,0x1D,0x1E,0x1F,
  596. 0x80,0x81,0x82,0x83,0x84,0x85,0x17,0x1B,0x88,0x89,0x8A,0x8B,0x8C,0x05,0x06,0x07,
  597. 0x90,0x91,0x16,0x93,0x94,0x95,0x96,0x04,0x98,0x99,0x9A,0x9B,0x14,0x15,0x9E,0x1A,
  598. 0x20,0xA0,0xE2,0xE4,0xE0,0xE1,0xE3,0xE5,0xE7,0xF1,0xA2,0x2E,0x3C,0x28,0x2B,0x7C,
  599. 0x26,0xE9,0xEA,0xEB,0xE8,0xED,0xEE,0xEF,0xEC,0xDF,0x21,0x24,0x2A,0x29,0x3B,0x5E,
  600. 0x2D,0x2F,0xC2,0xC4,0xC0,0xC1,0xC3,0xC5,0xC7,0xD1,0xA6,0x2C,0x25,0x5F,0x3E,0x3F,
  601. 0xF8,0xC9,0xCA,0xCB,0xC8,0xCD,0xCE,0xCF,0xCC,0x60,0x3A,0x23,0x40,0x27,0x3D,0x22,
  602. 0xD8,0x61,0x62,0x63,0x64,0x65,0x66,0x67,0x68,0x69,0xAB,0xBB,0xF0,0xFD,0xFE,0xB1,
  603. 0xB0,0x6A,0x6B,0x6C,0x6D,0x6E,0x6F,0x70,0x71,0x72,0xAA,0xBA,0xE6,0xB8,0xC6,0xA4,
  604. 0xB5,0x7E,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7A,0xA1,0xBF,0xD0,0x5B,0xDE,0xAE,
  605. 0xAC,0xA3,0xA5,0xB7,0xA9,0xA7,0xB6,0xBC,0xBD,0xBE,0xDD,0xA8,0xAF,0x5D,0xB4,0xD7,
  606. 0x7B,0x41,0x42,0x43,0x44,0x45,0x46,0x47,0x48,0x49,0xAD,0xF4,0xF6,0xF2,0xF3,0xF5,
  607. 0x7D,0x4A,0x4B,0x4C,0x4D,0x4E,0x4F,0x50,0x51,0x52,0xB9,0xFB,0xFC,0xF9,0xFA,0xFF,
  608. 0x5C,0xF7,0x53,0x54,0x55,0x56,0x57,0x58,0x59,0x5A,0xB2,0xD4,0xD6,0xD2,0xD3,0xD5,
  609. 0x30,0x31,0x32,0x33,0x34,0x35,0x36,0x37,0x38,0x39,0xB3,0xDB,0xDC,0xD9,0xDA,0x9F
  610. };
  611. #endif
  612. /*
  613. * Copy buf[0 ... nbytes-1] into out[], translating EBCDIC to ASCII.
  614. */
  615. private void
  616. from_ebcdic(const unsigned char *buf, size_t nbytes, unsigned char *out)
  617. {
  618. size_t i;
  619. for (i = 0; i < nbytes; i++) {
  620. out[i] = ebcdic_to_ascii[buf[i]];
  621. }
  622. }