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("@(#)$Id: ascmagic.c,v 1.41 2004/09/11 19:15:57 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[HOWMANY+1]; /* one extra for terminating '\0' */
  68. unichar ubuf[HOWMANY+1]; /* one extra for terminating '\0' */
  69. size_t ulen;
  70. struct names *p;
  71. const char *code = NULL;
  72. const char *code_mime = NULL;
  73. const char *type = NULL;
  74. const char *subtype = NULL;
  75. const char *subtype_mime = NULL;
  76. int has_escapes = 0;
  77. int has_backspace = 0;
  78. int n_crlf = 0;
  79. int n_lf = 0;
  80. int n_cr = 0;
  81. int n_nel = 0;
  82. int last_line_end = -1;
  83. int has_long_lines = 0;
  84. /*
  85. * Undo the NUL-termination kindly provided by process()
  86. * but leave at least one byte to look at
  87. */
  88. while (nbytes > 1 && buf[nbytes - 1] == '\0')
  89. nbytes--;
  90. /* nbuf and ubuf relies on this */
  91. if (nbytes > HOWMANY)
  92. nbytes = HOWMANY;
  93. /*
  94. * Then try to determine whether it's any character code we can
  95. * identify. Each of these tests, if it succeeds, will leave
  96. * the text converted into one-unichar-per-character Unicode in
  97. * ubuf, and the number of characters converted in ulen.
  98. */
  99. if (looks_ascii(buf, nbytes, ubuf, &ulen)) {
  100. code = "ASCII";
  101. code_mime = "us-ascii";
  102. type = "text";
  103. } else if (looks_utf8(buf, nbytes, ubuf, &ulen)) {
  104. code = "UTF-8 Unicode";
  105. code_mime = "utf-8";
  106. type = "text";
  107. } else if ((i = looks_unicode(buf, nbytes, ubuf, &ulen)) != 0) {
  108. if (i == 1)
  109. code = "Little-endian UTF-16 Unicode";
  110. else
  111. code = "Big-endian UTF-16 Unicode";
  112. type = "character data";
  113. code_mime = "utf-16"; /* is this defined? */
  114. } else if (looks_latin1(buf, nbytes, ubuf, &ulen)) {
  115. code = "ISO-8859";
  116. type = "text";
  117. code_mime = "iso-8859-1";
  118. } else if (looks_extended(buf, nbytes, ubuf, &ulen)) {
  119. code = "Non-ISO extended-ASCII";
  120. type = "text";
  121. code_mime = "unknown";
  122. } else {
  123. from_ebcdic(buf, nbytes, nbuf);
  124. if (looks_ascii(nbuf, nbytes, ubuf, &ulen)) {
  125. code = "EBCDIC";
  126. type = "character data";
  127. code_mime = "ebcdic";
  128. } else if (looks_latin1(nbuf, nbytes, ubuf, &ulen)) {
  129. code = "International EBCDIC";
  130. type = "character data";
  131. code_mime = "ebcdic";
  132. } else {
  133. return 0; /* doesn't look like text at all */
  134. }
  135. }
  136. /*
  137. * for troff, look for . + letter + letter or .\";
  138. * this must be done to disambiguate tar archives' ./file
  139. * and other trash from real troff input.
  140. *
  141. * I believe Plan 9 troff allows non-ASCII characters in the names
  142. * of macros, so this test might possibly fail on such a file.
  143. */
  144. if (*ubuf == '.') {
  145. unichar *tp = ubuf + 1;
  146. while (ISSPC(*tp))
  147. ++tp; /* skip leading whitespace */
  148. if ((tp[0] == '\\' && tp[1] == '\"') ||
  149. (isascii((unsigned char)tp[0]) &&
  150. isalnum((unsigned char)tp[0]) &&
  151. isascii((unsigned char)tp[1]) &&
  152. isalnum((unsigned char)tp[1]) &&
  153. ISSPC(tp[2]))) {
  154. subtype_mime = "text/troff";
  155. subtype = "troff or preprocessor input";
  156. goto subtype_identified;
  157. }
  158. }
  159. if ((*buf == 'c' || *buf == 'C') && ISSPC(buf[1])) {
  160. subtype_mime = "text/fortran";
  161. subtype = "fortran program";
  162. goto subtype_identified;
  163. }
  164. /* look for tokens from names.h - this is expensive! */
  165. i = 0;
  166. while (i < ulen) {
  167. size_t end;
  168. /*
  169. * skip past any leading space
  170. */
  171. while (i < ulen && ISSPC(ubuf[i]))
  172. i++;
  173. if (i >= ulen)
  174. break;
  175. /*
  176. * find the next whitespace
  177. */
  178. for (end = i + 1; end < nbytes; end++)
  179. if (ISSPC(ubuf[end]))
  180. break;
  181. /*
  182. * compare the word thus isolated against the token list
  183. */
  184. for (p = names; p < names + NNAMES; p++) {
  185. if (ascmatch((const unsigned char *)p->name, ubuf + i,
  186. end - i)) {
  187. subtype = types[p->type].human;
  188. subtype_mime = types[p->type].mime;
  189. goto subtype_identified;
  190. }
  191. }
  192. i = end;
  193. }
  194. subtype_identified:
  195. /*
  196. * Now try to discover other details about the file.
  197. */
  198. for (i = 0; i < ulen; i++) {
  199. if (i > last_line_end + MAXLINELEN)
  200. has_long_lines = 1;
  201. if (ubuf[i] == '\033')
  202. has_escapes = 1;
  203. if (ubuf[i] == '\b')
  204. has_backspace = 1;
  205. if (ubuf[i] == '\r' && (i + 1 < ulen && ubuf[i + 1] == '\n')) {
  206. n_crlf++;
  207. last_line_end = i;
  208. }
  209. if (ubuf[i] == '\r' && (i + 1 >= ulen || ubuf[i + 1] != '\n')) {
  210. n_cr++;
  211. last_line_end = i;
  212. }
  213. if (ubuf[i] == '\n' && ((int)i - 1 < 0 || ubuf[i - 1] != '\r')){
  214. n_lf++;
  215. last_line_end = i;
  216. }
  217. if (ubuf[i] == 0x85) { /* X3.64/ECMA-43 "next line" character */
  218. n_nel++;
  219. last_line_end = i;
  220. }
  221. }
  222. if ((ms->flags & MAGIC_MIME)) {
  223. if (subtype_mime) {
  224. if (file_printf(ms, subtype_mime) == -1)
  225. return -1;
  226. } else {
  227. if (file_printf(ms, "text/plain") == -1)
  228. return -1;
  229. }
  230. if (code_mime) {
  231. if (file_printf(ms, "; charset=") == -1)
  232. return -1;
  233. if (file_printf(ms, code_mime) == -1)
  234. return -1;
  235. }
  236. } else {
  237. if (file_printf(ms, code) == -1)
  238. return -1;
  239. if (subtype) {
  240. if (file_printf(ms, " ") == -1)
  241. return -1;
  242. if (file_printf(ms, subtype) == -1)
  243. return -1;
  244. }
  245. if (file_printf(ms, " ") == -1)
  246. return -1;
  247. if (file_printf(ms, type) == -1)
  248. return -1;
  249. if (has_long_lines)
  250. if (file_printf(ms, ", with very long lines") == -1)
  251. return -1;
  252. /*
  253. * Only report line terminators if we find one other than LF,
  254. * or if we find none at all.
  255. */
  256. if ((n_crlf == 0 && n_cr == 0 && n_nel == 0 && n_lf == 0) ||
  257. (n_crlf != 0 || n_cr != 0 || n_nel != 0)) {
  258. if (file_printf(ms, ", with") == -1)
  259. return -1;
  260. if (n_crlf == 0 && n_cr == 0 && n_nel == 0 && n_lf == 0) {
  261. if (file_printf(ms, " no") == -1)
  262. return -1;
  263. } else {
  264. if (n_crlf) {
  265. if (file_printf(ms, " CRLF") == -1)
  266. return -1;
  267. if (n_cr || n_lf || n_nel)
  268. if (file_printf(ms, ",") == -1)
  269. return -1;
  270. }
  271. if (n_cr) {
  272. if (file_printf(ms, " CR") == -1)
  273. return -1;
  274. if (n_lf || n_nel)
  275. if (file_printf(ms, ",") == -1)
  276. return -1;
  277. }
  278. if (n_lf) {
  279. if (file_printf(ms, " LF") == -1)
  280. return -1;
  281. if (n_nel)
  282. if (file_printf(ms, ",") == -1)
  283. return -1;
  284. }
  285. if (n_nel)
  286. if (file_printf(ms, " NEL") == -1)
  287. return -1;
  288. }
  289. if (file_printf(ms, " line terminators") == -1)
  290. return -1;
  291. }
  292. if (has_escapes)
  293. if (file_printf(ms, ", with escape sequences") == -1)
  294. return -1;
  295. if (has_backspace)
  296. if (file_printf(ms, ", with overstriking") == -1)
  297. return -1;
  298. }
  299. return 1;
  300. }
  301. private int
  302. ascmatch(const unsigned char *s, const unichar *us, size_t ulen)
  303. {
  304. size_t i;
  305. for (i = 0; i < ulen; i++) {
  306. if (s[i] != us[i])
  307. return 0;
  308. }
  309. if (s[i])
  310. return 0;
  311. else
  312. return 1;
  313. }
  314. /*
  315. * This table reflects a particular philosophy about what constitutes
  316. * "text," and there is room for disagreement about it.
  317. *
  318. * Version 3.31 of the file command considered a file to be ASCII if
  319. * each of its characters was approved by either the isascii() or
  320. * isalpha() function. On most systems, this would mean that any
  321. * file consisting only of characters in the range 0x00 ... 0x7F
  322. * would be called ASCII text, but many systems might reasonably
  323. * consider some characters outside this range to be alphabetic,
  324. * so the file command would call such characters ASCII. It might
  325. * have been more accurate to call this "considered textual on the
  326. * local system" than "ASCII."
  327. *
  328. * It considered a file to be "International language text" if each
  329. * of its characters was either an ASCII printing character (according
  330. * to the real ASCII standard, not the above test), a character in
  331. * the range 0x80 ... 0xFF, or one of the following control characters:
  332. * backspace, tab, line feed, vertical tab, form feed, carriage return,
  333. * escape. No attempt was made to determine the language in which files
  334. * of this type were written.
  335. *
  336. *
  337. * The table below considers a file to be ASCII if all of its characters
  338. * are either ASCII printing characters (again, according to the X3.4
  339. * standard, not isascii()) or any of the following controls: bell,
  340. * backspace, tab, line feed, form feed, carriage return, esc, nextline.
  341. *
  342. * I include bell because some programs (particularly shell scripts)
  343. * use it literally, even though it is rare in normal text. I exclude
  344. * vertical tab because it never seems to be used in real text. I also
  345. * include, with hesitation, the X3.64/ECMA-43 control nextline (0x85),
  346. * because that's what the dd EBCDIC->ASCII table maps the EBCDIC newline
  347. * character to. It might be more appropriate to include it in the 8859
  348. * set instead of the ASCII set, but it's got to be included in *something*
  349. * we recognize or EBCDIC files aren't going to be considered textual.
  350. * Some old Unix source files use SO/SI (^N/^O) to shift between Greek
  351. * and Latin characters, so these should possibly be allowed. But they
  352. * make a real mess on VT100-style displays if they're not paired properly,
  353. * so we are probably better off not calling them text.
  354. *
  355. * A file is considered to be ISO-8859 text if its characters are all
  356. * either ASCII, according to the above definition, or printing characters
  357. * from the ISO-8859 8-bit extension, characters 0xA0 ... 0xFF.
  358. *
  359. * Finally, a file is considered to be international text from some other
  360. * character code if its characters are all either ISO-8859 (according to
  361. * the above definition) or characters in the range 0x80 ... 0x9F, which
  362. * ISO-8859 considers to be control characters but the IBM PC and Macintosh
  363. * consider to be printing characters.
  364. */
  365. #define F 0 /* character never appears in text */
  366. #define T 1 /* character appears in plain ASCII text */
  367. #define I 2 /* character appears in ISO-8859 text */
  368. #define X 3 /* character appears in non-ISO extended ASCII (Mac, IBM PC) */
  369. private char text_chars[256] = {
  370. /* BEL BS HT LF FF CR */
  371. F, F, F, F, F, F, F, T, T, T, T, F, T, T, F, F, /* 0x0X */
  372. /* ESC */
  373. F, F, F, F, F, F, F, F, F, F, F, T, F, F, F, F, /* 0x1X */
  374. T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, /* 0x2X */
  375. T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, /* 0x3X */
  376. T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, /* 0x4X */
  377. T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, /* 0x5X */
  378. T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, /* 0x6X */
  379. T, T, T, T, T, T, T, T, T, T, T, T, T, T, T, F, /* 0x7X */
  380. /* NEL */
  381. X, X, X, X, X, T, X, X, X, X, X, X, X, X, X, X, /* 0x8X */
  382. X, X, X, X, X, X, X, X, X, X, X, X, X, X, X, X, /* 0x9X */
  383. I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, /* 0xaX */
  384. I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, /* 0xbX */
  385. I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, /* 0xcX */
  386. I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, /* 0xdX */
  387. I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, /* 0xeX */
  388. I, I, I, I, I, I, I, I, I, I, I, I, I, I, I, I /* 0xfX */
  389. };
  390. private int
  391. looks_ascii(const unsigned char *buf, size_t nbytes, unichar *ubuf,
  392. size_t *ulen)
  393. {
  394. int i;
  395. *ulen = 0;
  396. for (i = 0; i < nbytes; i++) {
  397. int t = text_chars[buf[i]];
  398. if (t != T)
  399. return 0;
  400. ubuf[(*ulen)++] = buf[i];
  401. }
  402. return 1;
  403. }
  404. private int
  405. looks_latin1(const unsigned char *buf, size_t nbytes, unichar *ubuf, size_t *ulen)
  406. {
  407. int i;
  408. *ulen = 0;
  409. for (i = 0; i < nbytes; i++) {
  410. int t = text_chars[buf[i]];
  411. if (t != T && t != I)
  412. return 0;
  413. ubuf[(*ulen)++] = buf[i];
  414. }
  415. return 1;
  416. }
  417. private int
  418. looks_extended(const unsigned char *buf, size_t nbytes, unichar *ubuf,
  419. size_t *ulen)
  420. {
  421. int i;
  422. *ulen = 0;
  423. for (i = 0; i < nbytes; i++) {
  424. int t = text_chars[buf[i]];
  425. if (t != T && t != I && t != X)
  426. return 0;
  427. ubuf[(*ulen)++] = buf[i];
  428. }
  429. return 1;
  430. }
  431. private int
  432. looks_utf8(const unsigned char *buf, size_t nbytes, unichar *ubuf, size_t *ulen)
  433. {
  434. int i, n;
  435. unichar c;
  436. int gotone = 0;
  437. *ulen = 0;
  438. for (i = 0; i < nbytes; i++) {
  439. if ((buf[i] & 0x80) == 0) { /* 0xxxxxxx is plain ASCII */
  440. /*
  441. * Even if the whole file is valid UTF-8 sequences,
  442. * still reject it if it uses weird control characters.
  443. */
  444. if (text_chars[buf[i]] != T)
  445. return 0;
  446. ubuf[(*ulen)++] = buf[i];
  447. } else if ((buf[i] & 0x40) == 0) { /* 10xxxxxx never 1st byte */
  448. return 0;
  449. } else { /* 11xxxxxx begins UTF-8 */
  450. int following;
  451. if ((buf[i] & 0x20) == 0) { /* 110xxxxx */
  452. c = buf[i] & 0x1f;
  453. following = 1;
  454. } else if ((buf[i] & 0x10) == 0) { /* 1110xxxx */
  455. c = buf[i] & 0x0f;
  456. following = 2;
  457. } else if ((buf[i] & 0x08) == 0) { /* 11110xxx */
  458. c = buf[i] & 0x07;
  459. following = 3;
  460. } else if ((buf[i] & 0x04) == 0) { /* 111110xx */
  461. c = buf[i] & 0x03;
  462. following = 4;
  463. } else if ((buf[i] & 0x02) == 0) { /* 1111110x */
  464. c = buf[i] & 0x01;
  465. following = 5;
  466. } else
  467. return 0;
  468. for (n = 0; n < following; n++) {
  469. i++;
  470. if (i >= nbytes)
  471. goto done;
  472. if ((buf[i] & 0x80) == 0 || (buf[i] & 0x40))
  473. return 0;
  474. c = (c << 6) + (buf[i] & 0x3f);
  475. }
  476. ubuf[(*ulen)++] = c;
  477. gotone = 1;
  478. }
  479. }
  480. done:
  481. return gotone; /* don't claim it's UTF-8 if it's all 7-bit */
  482. }
  483. private int
  484. looks_unicode(const unsigned char *buf, size_t nbytes, unichar *ubuf,
  485. size_t *ulen)
  486. {
  487. int bigend;
  488. int i;
  489. if (nbytes < 2)
  490. return 0;
  491. if (buf[0] == 0xff && buf[1] == 0xfe)
  492. bigend = 0;
  493. else if (buf[0] == 0xfe && buf[1] == 0xff)
  494. bigend = 1;
  495. else
  496. return 0;
  497. *ulen = 0;
  498. for (i = 2; i + 1 < nbytes; i += 2) {
  499. /* XXX fix to properly handle chars > 65536 */
  500. if (bigend)
  501. ubuf[(*ulen)++] = buf[i + 1] + 256 * buf[i];
  502. else
  503. ubuf[(*ulen)++] = buf[i] + 256 * buf[i + 1];
  504. if (ubuf[*ulen - 1] == 0xfffe)
  505. return 0;
  506. if (ubuf[*ulen - 1] < 128 &&
  507. text_chars[(size_t)ubuf[*ulen - 1]] != T)
  508. return 0;
  509. }
  510. return 1 + bigend;
  511. }
  512. #undef F
  513. #undef T
  514. #undef I
  515. #undef X
  516. /*
  517. * This table maps each EBCDIC character to an (8-bit extended) ASCII
  518. * character, as specified in the rationale for the dd(1) command in
  519. * draft 11.2 (September, 1991) of the POSIX P1003.2 standard.
  520. *
  521. * Unfortunately it does not seem to correspond exactly to any of the
  522. * five variants of EBCDIC documented in IBM's _Enterprise Systems
  523. * Architecture/390: Principles of Operation_, SA22-7201-06, Seventh
  524. * Edition, July, 1999, pp. I-1 - I-4.
  525. *
  526. * Fortunately, though, all versions of EBCDIC, including this one, agree
  527. * on most of the printing characters that also appear in (7-bit) ASCII.
  528. * Of these, only '|', '!', '~', '^', '[', and ']' are in question at all.
  529. *
  530. * Fortunately too, there is general agreement that codes 0x00 through
  531. * 0x3F represent control characters, 0x41 a nonbreaking space, and the
  532. * remainder printing characters.
  533. *
  534. * This is sufficient to allow us to identify EBCDIC text and to distinguish
  535. * between old-style and internationalized examples of text.
  536. */
  537. private unsigned char ebcdic_to_ascii[] = {
  538. 0, 1, 2, 3, 156, 9, 134, 127, 151, 141, 142, 11, 12, 13, 14, 15,
  539. 16, 17, 18, 19, 157, 133, 8, 135, 24, 25, 146, 143, 28, 29, 30, 31,
  540. 128, 129, 130, 131, 132, 10, 23, 27, 136, 137, 138, 139, 140, 5, 6, 7,
  541. 144, 145, 22, 147, 148, 149, 150, 4, 152, 153, 154, 155, 20, 21, 158, 26,
  542. ' ', 160, 161, 162, 163, 164, 165, 166, 167, 168, 213, '.', '<', '(', '+', '|',
  543. '&', 169, 170, 171, 172, 173, 174, 175, 176, 177, '!', '$', '*', ')', ';', '~',
  544. '-', '/', 178, 179, 180, 181, 182, 183, 184, 185, 203, ',', '%', '_', '>', '?',
  545. 186, 187, 188, 189, 190, 191, 192, 193, 194, '`', ':', '#', '@', '\'','=', '"',
  546. 195, 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 196, 197, 198, 199, 200, 201,
  547. 202, 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', '^', 204, 205, 206, 207, 208,
  548. 209, 229, 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', 210, 211, 212, '[', 214, 215,
  549. 216, 217, 218, 219, 220, 221, 222, 223, 224, 225, 226, 227, 228, ']', 230, 231,
  550. '{', 'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 232, 233, 234, 235, 236, 237,
  551. '}', 'J', 'K', 'L', 'M', 'N', 'O', 'P', 'Q', 'R', 238, 239, 240, 241, 242, 243,
  552. '\\',159, 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 244, 245, 246, 247, 248, 249,
  553. '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 250, 251, 252, 253, 254, 255
  554. };
  555. #ifdef notdef
  556. /*
  557. * The following EBCDIC-to-ASCII table may relate more closely to reality,
  558. * or at least to modern reality. It comes from
  559. *
  560. * http://ftp.s390.ibm.com/products/oe/bpxqp9.html
  561. *
  562. * and maps the characters of EBCDIC code page 1047 (the code used for
  563. * Unix-derived software on IBM's 390 systems) to the corresponding
  564. * characters from ISO 8859-1.
  565. *
  566. * If this table is used instead of the above one, some of the special
  567. * cases for the NEL character can be taken out of the code.
  568. */
  569. private unsigned char ebcdic_1047_to_8859[] = {
  570. 0x00,0x01,0x02,0x03,0x9C,0x09,0x86,0x7F,0x97,0x8D,0x8E,0x0B,0x0C,0x0D,0x0E,0x0F,
  571. 0x10,0x11,0x12,0x13,0x9D,0x0A,0x08,0x87,0x18,0x19,0x92,0x8F,0x1C,0x1D,0x1E,0x1F,
  572. 0x80,0x81,0x82,0x83,0x84,0x85,0x17,0x1B,0x88,0x89,0x8A,0x8B,0x8C,0x05,0x06,0x07,
  573. 0x90,0x91,0x16,0x93,0x94,0x95,0x96,0x04,0x98,0x99,0x9A,0x9B,0x14,0x15,0x9E,0x1A,
  574. 0x20,0xA0,0xE2,0xE4,0xE0,0xE1,0xE3,0xE5,0xE7,0xF1,0xA2,0x2E,0x3C,0x28,0x2B,0x7C,
  575. 0x26,0xE9,0xEA,0xEB,0xE8,0xED,0xEE,0xEF,0xEC,0xDF,0x21,0x24,0x2A,0x29,0x3B,0x5E,
  576. 0x2D,0x2F,0xC2,0xC4,0xC0,0xC1,0xC3,0xC5,0xC7,0xD1,0xA6,0x2C,0x25,0x5F,0x3E,0x3F,
  577. 0xF8,0xC9,0xCA,0xCB,0xC8,0xCD,0xCE,0xCF,0xCC,0x60,0x3A,0x23,0x40,0x27,0x3D,0x22,
  578. 0xD8,0x61,0x62,0x63,0x64,0x65,0x66,0x67,0x68,0x69,0xAB,0xBB,0xF0,0xFD,0xFE,0xB1,
  579. 0xB0,0x6A,0x6B,0x6C,0x6D,0x6E,0x6F,0x70,0x71,0x72,0xAA,0xBA,0xE6,0xB8,0xC6,0xA4,
  580. 0xB5,0x7E,0x73,0x74,0x75,0x76,0x77,0x78,0x79,0x7A,0xA1,0xBF,0xD0,0x5B,0xDE,0xAE,
  581. 0xAC,0xA3,0xA5,0xB7,0xA9,0xA7,0xB6,0xBC,0xBD,0xBE,0xDD,0xA8,0xAF,0x5D,0xB4,0xD7,
  582. 0x7B,0x41,0x42,0x43,0x44,0x45,0x46,0x47,0x48,0x49,0xAD,0xF4,0xF6,0xF2,0xF3,0xF5,
  583. 0x7D,0x4A,0x4B,0x4C,0x4D,0x4E,0x4F,0x50,0x51,0x52,0xB9,0xFB,0xFC,0xF9,0xFA,0xFF,
  584. 0x5C,0xF7,0x53,0x54,0x55,0x56,0x57,0x58,0x59,0x5A,0xB2,0xD4,0xD6,0xD2,0xD3,0xD5,
  585. 0x30,0x31,0x32,0x33,0x34,0x35,0x36,0x37,0x38,0x39,0xB3,0xDB,0xDC,0xD9,0xDA,0x9F
  586. };
  587. #endif
  588. /*
  589. * Copy buf[0 ... nbytes-1] into out[], translating EBCDIC to ASCII.
  590. */
  591. private void
  592. from_ebcdic(const unsigned char *buf, size_t nbytes, unsigned char *out)
  593. {
  594. int i;
  595. for (i = 0; i < nbytes; i++) {
  596. out[i] = ebcdic_to_ascii[buf[i]];
  597. }
  598. }