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1 | /* |
2 | * Copyright (c) 1989 The Regents of the University of California. | |
3 | * All rights reserved. | |
4 | * | |
5 | * This code is derived from software contributed to Berkeley by | |
a93b814a | 6 | * Ozan Yigit at York University. |
5597fa04 | 7 | * |
6ecf3d85 | 8 | * %sccs.include.redist.c% |
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9 | */ |
10 | ||
11 | #ifndef lint | |
a93b814a | 12 | static char sccsid[] = "@(#)eval.c 5.8 (Berkeley) %G%"; |
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13 | #endif /* not lint */ |
14 | ||
15 | /* | |
16 | * eval.c | |
17 | * Facility: m4 macro processor | |
18 | * by: oz | |
19 | */ | |
20 | ||
ba487a99 KB |
21 | #include <sys/types.h> |
22 | #include <errno.h> | |
50841d34 KB |
23 | #include <unistd.h> |
24 | #include <stdio.h> | |
25 | #include <stdlib.h> | |
26 | #include <string.h> | |
5597fa04 | 27 | #include "mdef.h" |
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28 | #include "stdd.h" |
29 | #include "extern.h" | |
30 | #include "pathnames.h" | |
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31 | |
32 | /* | |
33 | * eval - evaluate built-in macros. | |
34 | * argc - number of elements in argv. | |
35 | * argv - element vector : | |
36 | * argv[0] = definition of a user | |
37 | * macro or nil if built-in. | |
38 | * argv[1] = name of the macro or | |
39 | * built-in. | |
40 | * argv[2] = parameters to user-defined | |
41 | * . macro or built-in. | |
42 | * . | |
43 | * | |
44 | * Note that the minimum value for argc is 3. A call in the form | |
45 | * of macro-or-builtin() will result in: | |
46 | * argv[0] = nullstr | |
47 | * argv[1] = macro-or-builtin | |
48 | * argv[2] = nullstr | |
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49 | */ |
50 | ||
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51 | void |
52 | eval(argv, argc, td) | |
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53 | register char *argv[]; |
54 | register int argc; | |
ba487a99 | 55 | register int td; |
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56 | { |
57 | register int c, n; | |
ba487a99 | 58 | static int sysval = 0; |
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59 | |
60 | #ifdef DEBUG | |
61 | printf("argc = %d\n", argc); | |
62 | for (n = 0; n < argc; n++) | |
63 | printf("argv[%d] = %s\n", n, argv[n]); | |
64 | #endif | |
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65 | /* |
66 | * if argc == 3 and argv[2] is null, then we | |
67 | * have macro-or-builtin() type call. We adjust | |
68 | * argc to avoid further checking.. | |
69 | */ | |
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70 | if (argc == 3 && !*(argv[2])) |
71 | argc--; | |
72 | ||
73 | switch (td & ~STATIC) { | |
74 | ||
75 | case DEFITYPE: | |
76 | if (argc > 2) | |
77 | dodefine(argv[2], (argc > 3) ? argv[3] : null); | |
78 | break; | |
79 | ||
80 | case PUSDTYPE: | |
81 | if (argc > 2) | |
82 | dopushdef(argv[2], (argc > 3) ? argv[3] : null); | |
83 | break; | |
84 | ||
85 | case DUMPTYPE: | |
86 | dodump(argv, argc); | |
87 | break; | |
88 | ||
89 | case EXPRTYPE: | |
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90 | /* |
91 | * doexpr - evaluate arithmetic | |
92 | * expression | |
93 | */ | |
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94 | if (argc > 2) |
95 | pbnum(expr(argv[2])); | |
96 | break; | |
97 | ||
98 | case IFELTYPE: | |
99 | if (argc > 4) | |
100 | doifelse(argv, argc); | |
101 | break; | |
102 | ||
103 | case IFDFTYPE: | |
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104 | /* |
105 | * doifdef - select one of two | |
106 | * alternatives based on the existence of | |
107 | * another definition | |
108 | */ | |
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109 | if (argc > 3) { |
110 | if (lookup(argv[2]) != nil) | |
111 | pbstr(argv[3]); | |
112 | else if (argc > 4) | |
113 | pbstr(argv[4]); | |
114 | } | |
115 | break; | |
116 | ||
117 | case LENGTYPE: | |
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118 | /* |
119 | * dolen - find the length of the | |
120 | * argument | |
121 | */ | |
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122 | if (argc > 2) |
123 | pbnum((argc > 2) ? strlen(argv[2]) : 0); | |
124 | break; | |
125 | ||
126 | case INCRTYPE: | |
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127 | /* |
128 | * doincr - increment the value of the | |
129 | * argument | |
130 | */ | |
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131 | if (argc > 2) |
132 | pbnum(atoi(argv[2]) + 1); | |
133 | break; | |
134 | ||
135 | case DECRTYPE: | |
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136 | /* |
137 | * dodecr - decrement the value of the | |
138 | * argument | |
139 | */ | |
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140 | if (argc > 2) |
141 | pbnum(atoi(argv[2]) - 1); | |
142 | break; | |
143 | ||
5597fa04 | 144 | case SYSCTYPE: |
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145 | /* |
146 | * dosys - execute system command | |
147 | */ | |
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148 | if (argc > 2) |
149 | sysval = system(argv[2]); | |
150 | break; | |
151 | ||
152 | case SYSVTYPE: | |
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153 | /* |
154 | * dosysval - return value of the last | |
155 | * system call. | |
156 | * | |
157 | */ | |
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158 | pbnum(sysval); |
159 | break; | |
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160 | |
161 | case INCLTYPE: | |
162 | if (argc > 2) | |
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163 | if (!doincl(argv[2])) |
164 | oops("%s: %s", argv[2], strerror(errno)); | |
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165 | break; |
166 | ||
167 | case SINCTYPE: | |
168 | if (argc > 2) | |
169 | (void) doincl(argv[2]); | |
170 | break; | |
171 | #ifdef EXTENDED | |
172 | case PASTTYPE: | |
173 | if (argc > 2) | |
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174 | if (!dopaste(argv[2])) |
175 | oops("%s: %s", argv[2], strerror(errno)); | |
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176 | break; |
177 | ||
178 | case SPASTYPE: | |
179 | if (argc > 2) | |
180 | (void) dopaste(argv[2]); | |
181 | break; | |
182 | #endif | |
183 | case CHNQTYPE: | |
184 | dochq(argv, argc); | |
185 | break; | |
186 | ||
187 | case CHNCTYPE: | |
188 | dochc(argv, argc); | |
189 | break; | |
190 | ||
191 | case SUBSTYPE: | |
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192 | /* |
193 | * dosub - select substring | |
194 | * | |
195 | */ | |
5597fa04 | 196 | if (argc > 3) |
ba487a99 | 197 | dosub(argv, argc); |
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198 | break; |
199 | ||
200 | case SHIFTYPE: | |
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201 | /* |
202 | * doshift - push back all arguments | |
203 | * except the first one (i.e. skip | |
204 | * argv[2]) | |
205 | */ | |
5597fa04 | 206 | if (argc > 3) { |
ba487a99 | 207 | for (n = argc - 1; n > 3; n--) { |
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208 | putback(rquote); |
209 | pbstr(argv[n]); | |
210 | putback(lquote); | |
211 | putback(','); | |
212 | } | |
213 | putback(rquote); | |
214 | pbstr(argv[3]); | |
215 | putback(lquote); | |
216 | } | |
217 | break; | |
218 | ||
219 | case DIVRTYPE: | |
220 | if (argc > 2 && (n = atoi(argv[2])) != 0) | |
221 | dodiv(n); | |
222 | else { | |
223 | active = stdout; | |
224 | oindex = 0; | |
225 | } | |
226 | break; | |
227 | ||
228 | case UNDVTYPE: | |
229 | doundiv(argv, argc); | |
230 | break; | |
231 | ||
232 | case DIVNTYPE: | |
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233 | /* |
234 | * dodivnum - return the number of | |
235 | * current output diversion | |
236 | */ | |
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237 | pbnum(oindex); |
238 | break; | |
239 | ||
240 | case UNDFTYPE: | |
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241 | /* |
242 | * doundefine - undefine a previously | |
243 | * defined macro(s) or m4 keyword(s). | |
244 | */ | |
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245 | if (argc > 2) |
246 | for (n = 2; n < argc; n++) | |
247 | remhash(argv[n], ALL); | |
248 | break; | |
249 | ||
250 | case POPDTYPE: | |
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251 | /* |
252 | * dopopdef - remove the topmost | |
253 | * definitions of macro(s) or m4 | |
254 | * keyword(s). | |
255 | */ | |
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256 | if (argc > 2) |
257 | for (n = 2; n < argc; n++) | |
258 | remhash(argv[n], TOP); | |
259 | break; | |
260 | ||
261 | case MKTMTYPE: | |
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262 | /* |
263 | * dotemp - create a temporary file | |
264 | */ | |
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265 | if (argc > 2) |
266 | pbstr(mktemp(argv[2])); | |
267 | break; | |
268 | ||
269 | case TRNLTYPE: | |
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270 | /* |
271 | * dotranslit - replace all characters in | |
272 | * the source string that appears in the | |
273 | * "from" string with the corresponding | |
274 | * characters in the "to" string. | |
275 | */ | |
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276 | if (argc > 3) { |
277 | char temp[MAXTOK]; | |
278 | if (argc > 4) | |
279 | map(temp, argv[2], argv[3], argv[4]); | |
280 | else | |
281 | map(temp, argv[2], argv[3], null); | |
282 | pbstr(temp); | |
283 | } | |
ba487a99 | 284 | else if (argc > 2) |
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285 | pbstr(argv[2]); |
286 | break; | |
287 | ||
288 | case INDXTYPE: | |
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289 | /* |
290 | * doindex - find the index of the second | |
291 | * argument string in the first argument | |
292 | * string. -1 if not present. | |
293 | */ | |
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294 | pbnum((argc > 3) ? indx(argv[2], argv[3]) : -1); |
295 | break; | |
296 | ||
297 | case ERRPTYPE: | |
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298 | /* |
299 | * doerrp - print the arguments to stderr | |
300 | * file | |
301 | */ | |
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302 | if (argc > 2) { |
303 | for (n = 2; n < argc; n++) | |
ba487a99 | 304 | fprintf(stderr, "%s ", argv[n]); |
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305 | fprintf(stderr, "\n"); |
306 | } | |
307 | break; | |
308 | ||
309 | case DNLNTYPE: | |
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310 | /* |
311 | * dodnl - eat-up-to and including | |
312 | * newline | |
313 | */ | |
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314 | while ((c = gpbc()) != '\n' && c != EOF) |
315 | ; | |
316 | break; | |
317 | ||
318 | case M4WRTYPE: | |
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319 | /* |
320 | * dom4wrap - set up for | |
321 | * wrap-up/wind-down activity | |
322 | */ | |
323 | m4wraps = (argc > 2) ? xstrdup(argv[2]) : null; | |
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324 | break; |
325 | ||
326 | case EXITTYPE: | |
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327 | /* |
328 | * doexit - immediate exit from m4. | |
329 | */ | |
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330 | exit((argc > 2) ? atoi(argv[2]) : 0); |
331 | break; | |
332 | ||
333 | case DEFNTYPE: | |
334 | if (argc > 2) | |
335 | for (n = 2; n < argc; n++) | |
336 | dodefn(argv[n]); | |
337 | break; | |
338 | ||
339 | default: | |
ba487a99 | 340 | oops("%s: major botch.", "eval"); |
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341 | break; |
342 | } | |
343 | } | |
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344 | |
345 | char *dumpfmt = "`%s'\t`%s'\n"; /* format string for dumpdef */ | |
346 | ||
347 | /* | |
348 | * expand - user-defined macro expansion | |
349 | */ | |
350 | void | |
351 | expand(argv, argc) | |
352 | register char *argv[]; | |
353 | register int argc; | |
354 | { | |
355 | register char *t; | |
356 | register char *p; | |
357 | register int n; | |
358 | register int argno; | |
359 | ||
360 | t = argv[0]; /* defn string as a whole */ | |
361 | p = t; | |
362 | while (*p) | |
363 | p++; | |
364 | p--; /* last character of defn */ | |
365 | while (p > t) { | |
366 | if (*(p - 1) != ARGFLAG) | |
367 | putback(*p); | |
368 | else { | |
369 | switch (*p) { | |
370 | ||
371 | case '#': | |
372 | pbnum(argc - 2); | |
373 | break; | |
374 | case '0': | |
375 | case '1': | |
376 | case '2': | |
377 | case '3': | |
378 | case '4': | |
379 | case '5': | |
380 | case '6': | |
381 | case '7': | |
382 | case '8': | |
383 | case '9': | |
384 | if ((argno = *p - '0') < argc - 1) | |
385 | pbstr(argv[argno + 1]); | |
386 | break; | |
387 | case '*': | |
388 | for (n = argc - 1; n > 2; n--) { | |
389 | pbstr(argv[n]); | |
390 | putback(','); | |
391 | } | |
392 | pbstr(argv[2]); | |
393 | break; | |
394 | default: | |
395 | putback(*p); | |
b2a9b92b | 396 | putback('$'); |
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397 | break; |
398 | } | |
399 | p--; | |
400 | } | |
401 | p--; | |
402 | } | |
403 | if (p == t) /* do last character */ | |
404 | putback(*p); | |
405 | } | |
406 | ||
407 | /* | |
408 | * dodefine - install definition in the table | |
409 | */ | |
410 | void | |
411 | dodefine(name, defn) | |
412 | register char *name; | |
413 | register char *defn; | |
414 | { | |
415 | register ndptr p; | |
416 | ||
417 | if (!*name) | |
418 | oops("null definition."); | |
419 | if (STREQ(name, defn)) | |
420 | oops("%s: recursive definition.", name); | |
421 | if ((p = lookup(name)) == nil) | |
422 | p = addent(name); | |
423 | else if (p->defn != null) | |
424 | free((char *) p->defn); | |
425 | if (!*defn) | |
426 | p->defn = null; | |
427 | else | |
428 | p->defn = xstrdup(defn); | |
429 | p->type = MACRTYPE; | |
430 | } | |
431 | ||
432 | /* | |
433 | * dodefn - push back a quoted definition of | |
434 | * the given name. | |
435 | */ | |
436 | void | |
437 | dodefn(name) | |
438 | char *name; | |
439 | { | |
440 | register ndptr p; | |
441 | ||
442 | if ((p = lookup(name)) != nil && p->defn != null) { | |
443 | putback(rquote); | |
444 | pbstr(p->defn); | |
445 | putback(lquote); | |
446 | } | |
447 | } | |
448 | ||
449 | /* | |
450 | * dopushdef - install a definition in the hash table | |
451 | * without removing a previous definition. Since | |
452 | * each new entry is entered in *front* of the | |
453 | * hash bucket, it hides a previous definition from | |
454 | * lookup. | |
455 | */ | |
456 | void | |
457 | dopushdef(name, defn) | |
458 | register char *name; | |
459 | register char *defn; | |
460 | { | |
461 | register ndptr p; | |
462 | ||
463 | if (!*name) | |
464 | oops("null definition"); | |
465 | if (STREQ(name, defn)) | |
466 | oops("%s: recursive definition.", name); | |
467 | p = addent(name); | |
468 | if (!*defn) | |
469 | p->defn = null; | |
470 | else | |
471 | p->defn = xstrdup(defn); | |
472 | p->type = MACRTYPE; | |
473 | } | |
474 | ||
475 | /* | |
476 | * dodumpdef - dump the specified definitions in the hash | |
477 | * table to stderr. If nothing is specified, the entire | |
478 | * hash table is dumped. | |
479 | */ | |
480 | void | |
481 | dodump(argv, argc) | |
482 | register char *argv[]; | |
483 | register int argc; | |
484 | { | |
485 | register int n; | |
486 | ndptr p; | |
487 | ||
488 | if (argc > 2) { | |
489 | for (n = 2; n < argc; n++) | |
490 | if ((p = lookup(argv[n])) != nil) | |
491 | fprintf(stderr, dumpfmt, p->name, | |
492 | p->defn); | |
493 | } | |
494 | else { | |
495 | for (n = 0; n < HASHSIZE; n++) | |
496 | for (p = hashtab[n]; p != nil; p = p->nxtptr) | |
497 | fprintf(stderr, dumpfmt, p->name, | |
498 | p->defn); | |
499 | } | |
500 | } | |
501 | ||
502 | /* | |
503 | * doifelse - select one of two alternatives - loop. | |
504 | */ | |
505 | void | |
506 | doifelse(argv, argc) | |
507 | register char *argv[]; | |
508 | register int argc; | |
509 | { | |
510 | cycle { | |
511 | if (STREQ(argv[2], argv[3])) | |
512 | pbstr(argv[4]); | |
513 | else if (argc == 6) | |
514 | pbstr(argv[5]); | |
515 | else if (argc > 6) { | |
516 | argv += 3; | |
517 | argc -= 3; | |
518 | continue; | |
519 | } | |
520 | break; | |
521 | } | |
522 | } | |
523 | ||
524 | /* | |
525 | * doinclude - include a given file. | |
526 | */ | |
527 | int | |
528 | doincl(ifile) | |
529 | char *ifile; | |
530 | { | |
531 | if (ilevel + 1 == MAXINP) | |
532 | oops("too many include files."); | |
533 | if ((infile[ilevel + 1] = fopen(ifile, "r")) != NULL) { | |
534 | ilevel++; | |
1fbb93e0 | 535 | bbase[ilevel] = bufbase = bp; |
ba487a99 KB |
536 | return (1); |
537 | } | |
538 | else | |
539 | return (0); | |
540 | } | |
541 | ||
542 | #ifdef EXTENDED | |
543 | /* | |
544 | * dopaste - include a given file without any | |
545 | * macro processing. | |
546 | */ | |
547 | int | |
548 | dopaste(pfile) | |
549 | char *pfile; | |
550 | { | |
551 | FILE *pf; | |
552 | register int c; | |
553 | ||
554 | if ((pf = fopen(pfile, "r")) != NULL) { | |
555 | while ((c = getc(pf)) != EOF) | |
556 | putc(c, active); | |
557 | (void) fclose(pf); | |
558 | return (1); | |
559 | } | |
560 | else | |
561 | return (0); | |
562 | } | |
563 | #endif | |
564 | ||
565 | /* | |
566 | * dochq - change quote characters | |
567 | */ | |
568 | void | |
569 | dochq(argv, argc) | |
570 | register char *argv[]; | |
571 | register int argc; | |
572 | { | |
573 | if (argc > 2) { | |
574 | if (*argv[2]) | |
575 | lquote = *argv[2]; | |
576 | if (argc > 3) { | |
577 | if (*argv[3]) | |
578 | rquote = *argv[3]; | |
579 | } | |
580 | else | |
581 | rquote = lquote; | |
582 | } | |
583 | else { | |
584 | lquote = LQUOTE; | |
585 | rquote = RQUOTE; | |
586 | } | |
587 | } | |
588 | ||
589 | /* | |
590 | * dochc - change comment characters | |
591 | */ | |
592 | void | |
593 | dochc(argv, argc) | |
594 | register char *argv[]; | |
595 | register int argc; | |
596 | { | |
597 | if (argc > 2) { | |
598 | if (*argv[2]) | |
599 | scommt = *argv[2]; | |
600 | if (argc > 3) { | |
601 | if (*argv[3]) | |
602 | ecommt = *argv[3]; | |
603 | } | |
604 | else | |
605 | ecommt = ECOMMT; | |
606 | } | |
607 | else { | |
608 | scommt = SCOMMT; | |
609 | ecommt = ECOMMT; | |
610 | } | |
611 | } | |
612 | ||
613 | /* | |
614 | * dodivert - divert the output to a temporary file | |
615 | */ | |
616 | void | |
617 | dodiv(n) | |
618 | register int n; | |
619 | { | |
620 | if (n < 0 || n >= MAXOUT) | |
621 | n = 0; /* bitbucket */ | |
622 | if (outfile[n] == NULL) { | |
623 | m4temp[UNIQUE] = n + '0'; | |
624 | if ((outfile[n] = fopen(m4temp, "w")) == NULL) | |
625 | oops("%s: cannot divert.", m4temp); | |
626 | } | |
627 | oindex = n; | |
628 | active = outfile[n]; | |
629 | } | |
630 | ||
631 | /* | |
632 | * doundivert - undivert a specified output, or all | |
633 | * other outputs, in numerical order. | |
634 | */ | |
635 | void | |
636 | doundiv(argv, argc) | |
637 | register char *argv[]; | |
638 | register int argc; | |
639 | { | |
640 | register int ind; | |
641 | register int n; | |
642 | ||
643 | if (argc > 2) { | |
644 | for (ind = 2; ind < argc; ind++) { | |
645 | n = atoi(argv[ind]); | |
646 | if (n > 0 && n < MAXOUT && outfile[n] != NULL) | |
647 | getdiv(n); | |
648 | ||
649 | } | |
650 | } | |
651 | else | |
652 | for (n = 1; n < MAXOUT; n++) | |
653 | if (outfile[n] != NULL) | |
654 | getdiv(n); | |
655 | } | |
656 | ||
657 | /* | |
658 | * dosub - select substring | |
659 | */ | |
660 | void | |
661 | dosub(argv, argc) | |
662 | register char *argv[]; | |
663 | register int argc; | |
664 | { | |
665 | register char *ap, *fc, *k; | |
666 | register int nc; | |
667 | ||
668 | if (argc < 5) | |
669 | nc = MAXTOK; | |
670 | else | |
671 | #ifdef EXPR | |
672 | nc = expr(argv[4]); | |
673 | #else | |
674 | nc = atoi(argv[4]); | |
675 | #endif | |
676 | ap = argv[2]; /* target string */ | |
677 | #ifdef EXPR | |
678 | fc = ap + expr(argv[3]); /* first char */ | |
679 | #else | |
680 | fc = ap + atoi(argv[3]); /* first char */ | |
681 | #endif | |
682 | if (fc >= ap && fc < ap + strlen(ap)) | |
683 | for (k = fc + min(nc, strlen(fc)) - 1; k >= fc; k--) | |
684 | putback(*k); | |
685 | } | |
686 | ||
687 | /* | |
688 | * map: | |
689 | * map every character of s1 that is specified in from | |
690 | * into s3 and replace in s. (source s1 remains untouched) | |
691 | * | |
692 | * This is a standard implementation of map(s,from,to) function of ICON | |
693 | * language. Within mapvec, we replace every character of "from" with | |
694 | * the corresponding character in "to". If "to" is shorter than "from", | |
695 | * than the corresponding entries are null, which means that those | |
696 | * characters dissapear altogether. Furthermore, imagine | |
697 | * map(dest, "sourcestring", "srtin", "rn..*") type call. In this case, | |
698 | * `s' maps to `r', `r' maps to `n' and `n' maps to `*'. Thus, `s' | |
699 | * ultimately maps to `*'. In order to achieve this effect in an efficient | |
700 | * manner (i.e. without multiple passes over the destination string), we | |
701 | * loop over mapvec, starting with the initial source character. if the | |
702 | * character value (dch) in this location is different than the source | |
703 | * character (sch), sch becomes dch, once again to index into mapvec, until | |
704 | * the character value stabilizes (i.e. sch = dch, in other words | |
705 | * mapvec[n] == n). Even if the entry in the mapvec is null for an ordinary | |
706 | * character, it will stabilize, since mapvec[0] == 0 at all times. At the | |
707 | * end, we restore mapvec* back to normal where mapvec[n] == n for | |
708 | * 0 <= n <= 127. This strategy, along with the restoration of mapvec, is | |
709 | * about 5 times faster than any algorithm that makes multiple passes over | |
710 | * destination string. | |
711 | */ | |
712 | void | |
713 | map(dest, src, from, to) | |
714 | register char *dest; | |
715 | register char *src; | |
716 | register char *from; | |
717 | register char *to; | |
718 | { | |
719 | register char *tmp; | |
720 | register char sch, dch; | |
721 | static char mapvec[128] = { | |
722 | 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, | |
723 | 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, | |
724 | 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, | |
725 | 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, | |
726 | 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, | |
727 | 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, | |
728 | 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, | |
729 | 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, | |
730 | 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, | |
731 | 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, | |
732 | 120, 121, 122, 123, 124, 125, 126, 127 | |
733 | }; | |
734 | ||
735 | if (*src) { | |
736 | tmp = from; | |
737 | /* | |
738 | * create a mapping between "from" and | |
739 | * "to" | |
740 | */ | |
741 | while (*from) | |
742 | mapvec[*from++] = (*to) ? *to++ : (char) 0; | |
743 | ||
744 | while (*src) { | |
745 | sch = *src++; | |
746 | dch = mapvec[sch]; | |
747 | while (dch != sch) { | |
748 | sch = dch; | |
749 | dch = mapvec[sch]; | |
750 | } | |
751 | if (*dest = dch) | |
752 | dest++; | |
753 | } | |
754 | /* | |
755 | * restore all the changed characters | |
756 | */ | |
757 | while (*tmp) { | |
758 | mapvec[*tmp] = *tmp; | |
759 | tmp++; | |
760 | } | |
761 | } | |
762 | *dest = (char) 0; | |
763 | } |