Commit | Line | Data |
---|---|---|
2de91bbb BJ |
1 | /* Copyright (c) 1979 Regents of the University of California */ |
2 | #include "ex.h" | |
3 | #include "ex_argv.h" | |
4 | #include "ex_temp.h" | |
5 | #include "ex_tty.h" | |
6 | ||
7 | /* | |
8 | * Command mode subroutines implementing | |
9 | * append, args, copy, delete, join, move, put, | |
10 | * shift, tag, yank, z and undo | |
11 | */ | |
12 | ||
13 | bool endline = 1; | |
14 | line *tad1; | |
15 | ||
16 | /* | |
17 | * Append after line a lines returned by function f. | |
18 | * Be careful about intermediate states to avoid scramble | |
19 | * if an interrupt comes in. | |
20 | */ | |
21 | append(f, a) | |
22 | int (*f)(); | |
23 | line *a; | |
24 | { | |
25 | register line *a1, *a2, *rdot; | |
26 | int nline; | |
27 | ||
28 | nline = 0; | |
29 | dot = a; | |
30 | if (!inglobal && !inopen && f != getsub) { | |
31 | undap1 = undap2 = dot + 1; | |
32 | undkind = UNDCHANGE; | |
33 | } | |
34 | while ((*f)() == 0) { | |
35 | if (truedol >= endcore) { | |
36 | if (morelines() < 0) { | |
37 | if (!inglobal && f == getsub) { | |
38 | undap1 = addr1; | |
39 | undap2 = addr2 + 1; | |
40 | } | |
41 | error("Out of memory@- too many lines in file"); | |
42 | } | |
43 | } | |
44 | nline++; | |
45 | a1 = truedol + 1; | |
46 | a2 = a1 + 1; | |
47 | dot++; | |
48 | undap2++; | |
49 | dol++; | |
50 | unddol++; | |
51 | truedol++; | |
52 | for (rdot = dot; a1 > rdot;) | |
53 | *--a2 = *--a1; | |
54 | *rdot = 0; | |
55 | putmark(rdot); | |
56 | if (f == gettty) { | |
57 | dirtcnt++; | |
58 | TSYNC(); | |
59 | } | |
60 | } | |
61 | return (nline); | |
62 | } | |
63 | ||
64 | appendnone() | |
65 | { | |
66 | ||
67 | if (!inglobal || inopen > 0) { | |
68 | undkind = UNDCHANGE; | |
69 | undap1 = undap2 = addr1; | |
70 | } | |
71 | } | |
72 | ||
73 | /* | |
74 | * Print out the argument list, with []'s around the current name. | |
75 | */ | |
76 | pargs() | |
77 | { | |
78 | register char **av = argv0, *as = args0; | |
79 | register int ac; | |
80 | ||
81 | for (ac = 0; ac < argc0; ac++) { | |
82 | if (ac != 0) | |
83 | putchar(' '); | |
84 | if (ac + argc == argc0 - 1) | |
85 | printf("["); | |
86 | lprintf("%s", as); | |
87 | if (ac + argc == argc0 - 1) | |
88 | printf("]"); | |
89 | as = av ? *++av : strend(as) + 1; | |
90 | } | |
91 | noonl(); | |
92 | } | |
93 | ||
94 | /* | |
95 | * Delete lines; two cases are if we are really deleting, | |
96 | * more commonly we are just moving lines to the undo save area. | |
97 | */ | |
98 | delete(hush) | |
99 | bool hush; | |
100 | { | |
101 | register line *a1, *a2; | |
102 | ||
103 | nonzero(); | |
104 | if (!inglobal || inopen > 0) { | |
105 | register int (*dsavint)(); | |
106 | ||
107 | change(); | |
108 | dsavint = signal(SIGINT, SIG_IGN); | |
109 | undkind = UNDCHANGE; | |
110 | a1 = addr1; | |
111 | squish(); | |
112 | a2 = addr2; | |
113 | if (a2++ != dol) { | |
114 | reverse(a1, a2); | |
115 | reverse(a2, dol + 1); | |
116 | reverse(a1, dol + 1); | |
117 | } | |
118 | dol -= a2 - a1; | |
119 | unddel = a1 - 1; | |
120 | if (a1 > dol) | |
121 | a1 = dol; | |
122 | dot = a1; | |
123 | pkill[0] = pkill[1] = 0; | |
124 | signal(SIGINT, dsavint); | |
125 | } else { | |
126 | register line *a3; | |
127 | register int i; | |
128 | ||
129 | change(); | |
130 | a1 = addr1; | |
131 | a2 = addr2 + 1; | |
132 | a3 = truedol; | |
133 | i = a2 - a1; | |
134 | unddol -= i; | |
135 | undap2 -= i; | |
136 | dol -= i; | |
137 | truedol -= i; | |
138 | do | |
139 | *a1++ = *a2++; | |
140 | while (a2 <= a3); | |
141 | a1 = addr1; | |
142 | if (a1 > dol) | |
143 | a1 = dol; | |
144 | dot = a1; | |
145 | } | |
146 | if (!hush) | |
147 | killed(); | |
148 | } | |
149 | ||
150 | deletenone() | |
151 | { | |
152 | ||
153 | if (!inglobal || inopen > 0) { | |
154 | undkind = UNDCHANGE; | |
155 | squish(); | |
156 | unddel = addr1; | |
157 | } | |
158 | } | |
159 | ||
160 | /* | |
161 | * Crush out the undo save area, moving the open/visual | |
162 | * save area down in its place. | |
163 | */ | |
164 | squish() | |
165 | { | |
166 | register line *a1 = dol + 1, *a2 = unddol + 1, *a3 = truedol + 1; | |
167 | ||
168 | if (a1 < a2 && a2 < a3) | |
169 | do | |
170 | *a1++ = *a2++; | |
171 | while (a2 < a3); | |
172 | truedol -= unddol - dol; | |
173 | unddol = dol; | |
174 | } | |
175 | ||
176 | /* | |
177 | * Join lines. Special hacks put in spaces, two spaces if | |
178 | * preceding line ends with '.', or no spaces if next line starts with ). | |
179 | */ | |
180 | static int jcount, jnoop(); | |
181 | ||
182 | join(c) | |
183 | int c; | |
184 | { | |
185 | register line *a1; | |
186 | register char *cp, *cp1; | |
187 | ||
188 | cp = genbuf; | |
189 | *cp = 0; | |
190 | for (a1 = addr1; a1 <= addr2; a1++) { | |
191 | getline(*a1); | |
192 | cp1 = linebuf; | |
193 | if (a1 != addr1 && c == 0) { | |
194 | while (*cp1 == ' ' || *cp1 == '\t') | |
195 | cp1++; | |
196 | if (*cp1 && cp > genbuf && cp[-1] != ' ' && cp[-1] != '\t') { | |
197 | if (*cp1 != ')') { | |
198 | *cp++ = ' '; | |
199 | if (cp[-2] == '.') | |
200 | *cp++ = ' '; | |
201 | } | |
202 | } | |
203 | } | |
204 | while (*cp++ = *cp1++) | |
205 | if (cp > &genbuf[LBSIZE-2]) | |
206 | error("Line overflow|Result line of join would be too long"); | |
207 | cp--; | |
208 | } | |
209 | strcLIN(genbuf); | |
210 | delete(0); | |
211 | jcount = 1; | |
212 | ignore(append(jnoop, --addr1)); | |
213 | } | |
214 | ||
215 | static | |
216 | jnoop() | |
217 | { | |
218 | ||
219 | return(--jcount); | |
220 | } | |
221 | ||
222 | /* | |
223 | * Move and copy lines. Hard work is done by move1 which | |
224 | * is also called by undo. | |
225 | */ | |
226 | int getcopy(); | |
227 | ||
228 | move() | |
229 | { | |
230 | register line *adt; | |
231 | bool iscopy = 0; | |
232 | ||
233 | if (Command[0] == 'm') { | |
234 | setdot1(); | |
235 | markpr(addr2 == dot ? addr1 - 1 : addr2 + 1); | |
236 | } else { | |
237 | iscopy++; | |
238 | setdot(); | |
239 | } | |
240 | nonzero(); | |
241 | adt = address(); | |
242 | if (adt == 0) | |
243 | serror("%s where?|%s requires a trailing address", Command); | |
244 | newline(); | |
245 | move1(iscopy, adt); | |
246 | killed(); | |
247 | } | |
248 | ||
249 | move1(cflag, addrt) | |
250 | int cflag; | |
251 | line *addrt; | |
252 | { | |
253 | register line *adt, *ad1, *ad2; | |
254 | int lines; | |
255 | ||
256 | adt = addrt; | |
257 | lines = (addr2 - addr1) + 1; | |
258 | if (cflag) { | |
259 | tad1 = addr1; | |
260 | ad1 = dol; | |
261 | ignore(append(getcopy, ad1++)); | |
262 | ad2 = dol; | |
263 | } else { | |
264 | ad2 = addr2; | |
265 | for (ad1 = addr1; ad1 <= ad2;) | |
266 | *ad1++ &= ~01; | |
267 | ad1 = addr1; | |
268 | } | |
269 | ad2++; | |
270 | if (adt < ad1) { | |
271 | if (adt + 1 == ad1 && !cflag && !inglobal) | |
272 | error("That move would do nothing!"); | |
273 | dot = adt + (ad2 - ad1); | |
274 | if (++adt != ad1) { | |
275 | reverse(adt, ad1); | |
276 | reverse(ad1, ad2); | |
277 | reverse(adt, ad2); | |
278 | } | |
279 | } else if (adt >= ad2) { | |
280 | dot = adt++; | |
281 | reverse(ad1, ad2); | |
282 | reverse(ad2, adt); | |
283 | reverse(ad1, adt); | |
284 | } else | |
285 | error("Move to a moved line"); | |
286 | change(); | |
287 | if (!inglobal) | |
288 | if (cflag) { | |
289 | undap1 = addrt + 1; | |
290 | undap2 = undap1 + lines; | |
291 | deletenone(); | |
292 | } else { | |
293 | undkind = UNDMOVE; | |
294 | undap1 = addr1; | |
295 | undap2 = addr2; | |
296 | unddel = addrt; | |
297 | squish(); | |
298 | } | |
299 | } | |
300 | ||
301 | getcopy() | |
302 | { | |
303 | ||
304 | if (tad1 > addr2) | |
305 | return (EOF); | |
306 | getline(*tad1++); | |
307 | return (0); | |
308 | } | |
309 | ||
310 | /* | |
311 | * Put lines in the buffer from the undo save area. | |
312 | */ | |
313 | getput() | |
314 | { | |
315 | ||
316 | if (tad1 > unddol) | |
317 | return (EOF); | |
318 | getline(*tad1++); | |
319 | tad1++; | |
320 | return (0); | |
321 | } | |
322 | ||
323 | put() | |
324 | { | |
325 | register int cnt; | |
326 | ||
327 | cnt = unddol - dol; | |
328 | if (cnt && inopen && pkill[0] && pkill[1]) { | |
329 | pragged(1); | |
330 | return; | |
331 | } | |
332 | tad1 = dol + 1; | |
333 | ignore(append(getput, addr2)); | |
334 | undkind = UNDPUT; | |
335 | notecnt = cnt; | |
336 | netchange(cnt); | |
337 | } | |
338 | ||
339 | /* | |
340 | * A tricky put, of a group of lines in the middle | |
341 | * of an existing line. Only from open/visual. | |
342 | * Argument says pkills have meaning, e.g. called from | |
343 | * put; it is 0 on calls from putreg. | |
344 | */ | |
345 | pragged(kill) | |
346 | bool kill; | |
347 | { | |
348 | extern char *cursor; | |
349 | register char *gp = &genbuf[cursor - linebuf]; | |
350 | ||
351 | /* | |
352 | * This kind of stuff is TECO's forte. | |
353 | * We just grunge along, since it cuts | |
354 | * across our line-oriented model of the world | |
355 | * almost scrambling our addled brain. | |
356 | */ | |
357 | if (!kill) | |
358 | getDOT(); | |
359 | strcpy(genbuf, linebuf); | |
360 | getline(*unddol); | |
361 | if (kill) | |
362 | *pkill[1] = 0; | |
363 | strcat(linebuf, gp); | |
364 | putmark(unddol); | |
365 | getline(dol[1]); | |
366 | if (kill) | |
367 | strcLIN(pkill[0]); | |
368 | strcpy(gp, linebuf); | |
369 | strcLIN(genbuf); | |
370 | putmark(dol+1); | |
371 | undkind = UNDCHANGE; | |
372 | undap1 = dot; | |
373 | undap2 = dot + 1; | |
374 | unddel = dot - 1; | |
375 | undo(1); | |
376 | } | |
377 | ||
378 | /* | |
379 | * Shift lines, based on c. | |
380 | * If c is neither < nor >, then this is a lisp aligning =. | |
381 | */ | |
382 | shift(c, cnt) | |
383 | int c; | |
384 | int cnt; | |
385 | { | |
386 | register line *addr; | |
387 | register char *cp; | |
388 | char *dp; | |
389 | register int i; | |
390 | ||
391 | if (!inglobal) | |
392 | save12(), undkind = UNDCHANGE; | |
393 | cnt *= value(SHIFTWIDTH); | |
394 | for (addr = addr1; addr <= addr2; addr++) { | |
395 | dot = addr; | |
396 | #ifdef LISP | |
397 | if (c == '=' && addr == addr1 && addr != addr2) | |
398 | continue; | |
399 | #endif | |
400 | getDOT(); | |
401 | i = whitecnt(linebuf); | |
402 | switch (c) { | |
403 | ||
404 | case '>': | |
405 | if (linebuf[0] == 0) | |
406 | continue; | |
407 | cp = genindent(i + cnt); | |
408 | break; | |
409 | ||
410 | case '<': | |
411 | if (i == 0) | |
412 | continue; | |
413 | i -= cnt; | |
414 | cp = i > 0 ? genindent(i) : genbuf; | |
415 | break; | |
416 | ||
417 | #ifdef LISP | |
418 | default: | |
419 | i = lindent(addr); | |
420 | getDOT(); | |
421 | cp = genindent(i); | |
422 | break; | |
423 | #endif | |
424 | } | |
425 | if (cp + strlen(dp = vpastwh(linebuf)) >= &genbuf[LBSIZE - 2]) | |
426 | error("Line too long|Result line after shift would be too long"); | |
427 | CP(cp, dp); | |
428 | strcLIN(genbuf); | |
429 | putmark(addr); | |
430 | } | |
431 | killed(); | |
432 | } | |
433 | ||
434 | /* | |
435 | * Find a tag in the tags file. | |
436 | * Most work here is in parsing the tags file itself. | |
437 | */ | |
438 | tagfind(quick) | |
439 | bool quick; | |
440 | { | |
441 | char cmdbuf[BUFSIZ]; | |
442 | register int c, d; | |
443 | bool samef = 1; | |
444 | short master = -1; | |
445 | ||
446 | intag = 1; | |
447 | if (!skipend()) { | |
448 | register char *lp = lasttag; | |
449 | ||
450 | while (!iswhite(peekchar()) && !endcmd(peekchar())) | |
451 | if (lp < &lasttag[sizeof lasttag - 2]) | |
452 | *lp++ = getchar(); | |
453 | else | |
454 | ignchar(); | |
455 | *lp++ = 0; | |
456 | if (!endcmd(peekchar())) | |
457 | badtag: | |
458 | error("Bad tag|Give one tag per line"); | |
459 | } else if (lasttag[0] == 0) | |
460 | error("No previous tag"); | |
461 | c = getchar(); | |
462 | if (!endcmd(c)) | |
463 | goto badtag; | |
464 | if (c == EOF) | |
465 | ungetchar(c); | |
466 | clrstats(); | |
467 | do { | |
468 | io = open(master ? "tags" : MASTERTAGS, 0); | |
469 | while (getfile() == 0) { | |
470 | register char *cp = linebuf; | |
471 | register char *lp = lasttag; | |
472 | char *oglobp; | |
473 | ||
474 | while (*cp && *lp == *cp) | |
475 | cp++, lp++; | |
476 | if (*lp || *cp != '\t') | |
477 | continue; | |
478 | close(io); | |
479 | while (*cp && iswhite(*cp)) | |
480 | cp++; | |
481 | if (!*cp) | |
482 | badtags: | |
483 | serror("%s: Bad tags file entry", lasttag); | |
484 | lp = file; | |
485 | while (*cp && *cp != ' ' && *cp != '\t') { | |
486 | if (lp < &file[sizeof file - 2]) | |
487 | *lp++ = *cp; | |
488 | cp++; | |
489 | } | |
490 | *lp++ = 0; | |
491 | if (*cp == 0) | |
492 | goto badtags; | |
493 | if (dol != zero) { | |
494 | /* | |
495 | * Save current position in 't for ^^ in visual. | |
496 | */ | |
497 | names['t'-'a'] = *dot &~ 01; | |
498 | if (inopen) { | |
499 | extern char *ncols['z'-'a'+1]; | |
500 | extern char *cursor; | |
501 | ||
502 | ncols['t'-'a'] = cursor; | |
503 | } | |
504 | } | |
505 | strcpy(cmdbuf, cp); | |
506 | if (strcmp(file, savedfile) || !edited) { | |
507 | char cmdbuf2[sizeof file + 10]; | |
508 | ||
509 | if (!quick && chng) | |
510 | error("No write@since last change (tag! overrides)"); | |
511 | oglobp = globp; | |
512 | strcpy(cmdbuf2, "e! "); | |
513 | strcat(cmdbuf2, file); | |
514 | globp = cmdbuf2; | |
515 | d = peekc; ungetchar(0); | |
516 | commands(1, 1); | |
517 | peekc = d; | |
518 | globp = oglobp; | |
519 | samef = 0; | |
520 | } | |
521 | oglobp = globp; | |
522 | globp = cmdbuf; | |
523 | d = peekc; ungetchar(0); | |
524 | if (samef) | |
525 | markpr(dot); | |
526 | commands(1, 1); | |
527 | peekc = d; | |
528 | globp = oglobp; | |
529 | intag = 0; | |
530 | return; | |
531 | } | |
532 | } while (++master == 0); | |
533 | serror("%s: No such tag@in tags file", lasttag); | |
534 | } | |
535 | ||
536 | /* | |
537 | * Save lines from addr1 thru addr2 as though | |
538 | * they had been deleted. | |
539 | */ | |
540 | yank() | |
541 | { | |
542 | ||
543 | save12(); | |
544 | undkind = UNDNONE; | |
545 | killcnt(addr2 - addr1 + 1); | |
546 | } | |
547 | ||
548 | /* | |
549 | * z command; print windows of text in the file. | |
550 | * | |
551 | * If this seems unreasonably arcane, the reasons | |
552 | * are historical. This is one of the first commands | |
553 | * added to the first ex (then called en) and the | |
554 | * number of facilities here were the major advantage | |
555 | * of en over ed since they allowed more use to be | |
556 | * made of fast terminals w/o typing .,.22p all the time. | |
557 | */ | |
558 | bool zhadpr; | |
559 | bool znoclear; | |
560 | short zweight; | |
561 | ||
562 | zop(hadpr) | |
563 | int hadpr; | |
564 | { | |
565 | register int c, lines, op; | |
566 | bool excl; | |
567 | ||
568 | zhadpr = hadpr; | |
569 | notempty(); | |
570 | znoclear = 0; | |
571 | zweight = 0; | |
572 | excl = exclam(); | |
573 | switch (c = op = getchar()) { | |
574 | ||
575 | case '^': | |
576 | zweight = 1; | |
577 | case '-': | |
578 | case '+': | |
579 | while (peekchar() == op) { | |
580 | ignchar(); | |
581 | zweight++; | |
582 | } | |
583 | case '=': | |
584 | case '.': | |
585 | c = getchar(); | |
586 | break; | |
587 | ||
588 | case EOF: | |
589 | znoclear++; | |
590 | break; | |
591 | ||
592 | default: | |
593 | op = 0; | |
594 | break; | |
595 | } | |
596 | if (isdigit(c)) { | |
597 | lines = c - '0'; | |
598 | for(;;) { | |
599 | c = getchar(); | |
600 | if (!isdigit(c)) | |
601 | break; | |
602 | lines *= 10; | |
603 | lines += c - '0'; | |
604 | } | |
605 | if (lines < value(WINDOW)) | |
606 | znoclear++; | |
607 | if (op == '=') | |
608 | lines += 2; | |
609 | } else | |
610 | lines = op == EOF ? value(SCROLL) : excl ? LINES - 1 : value(WINDOW); | |
611 | if (inopen || c != EOF) { | |
612 | ungetchar(c); | |
613 | newline(); | |
614 | } | |
615 | addr1 = addr2; | |
616 | setdot(); | |
617 | zop2(lines, op); | |
618 | } | |
619 | ||
620 | zop2(lines, op) | |
621 | register int lines; | |
622 | register int op; | |
623 | { | |
624 | register line *split; | |
625 | ||
626 | split = NULL; | |
627 | switch (op) { | |
628 | ||
629 | case EOF: | |
630 | if (addr2 == dol) | |
631 | error("\nAt EOF"); | |
632 | case '+': | |
633 | if (addr2 == dol) | |
634 | error("At EOF"); | |
635 | addr2 += lines * zweight; | |
636 | if (addr2 > dol) | |
637 | error("Hit BOTTOM"); | |
638 | addr2++; | |
639 | default: | |
640 | addr1 = addr2; | |
641 | addr2 += lines-1; | |
642 | dot = addr2; | |
643 | break; | |
644 | ||
645 | case '=': | |
646 | case '.': | |
647 | znoclear = 0; | |
648 | lines--; | |
649 | lines >>= 1; | |
650 | if (op == '=') | |
651 | lines--; | |
652 | addr1 = addr2 - lines; | |
653 | if (op == '=') | |
654 | dot = split = addr2; | |
655 | addr2 += lines; | |
656 | if (op == '.') { | |
657 | markDOT(); | |
658 | dot = addr2; | |
659 | } | |
660 | break; | |
661 | ||
662 | case '^': | |
663 | case '-': | |
664 | addr2 -= lines * zweight; | |
665 | if (addr2 < one) | |
666 | error("Hit TOP"); | |
667 | lines--; | |
668 | addr1 = addr2 - lines; | |
669 | dot = addr2; | |
670 | break; | |
671 | } | |
672 | if (addr1 <= zero) | |
673 | addr1 = one; | |
674 | if (addr2 > dol) | |
675 | addr2 = dol; | |
676 | if (dot > dol) | |
677 | dot = dol; | |
678 | if (addr1 > addr2) | |
679 | return; | |
680 | if (op == EOF && zhadpr) { | |
681 | getline(*addr1); | |
682 | putchar('\r' | QUOTE); | |
683 | shudclob = 1; | |
684 | } else if (znoclear == 0 && CL != NOSTR && !inopen) { | |
685 | flush1(); | |
686 | vclear(); | |
687 | } | |
688 | if (addr2 - addr1 > 1) | |
689 | pstart(); | |
690 | if (split) { | |
691 | plines(addr1, split - 1, 0); | |
692 | splitit(); | |
693 | plines(split, split, 0); | |
694 | splitit(); | |
695 | addr1 = split + 1; | |
696 | } | |
697 | plines(addr1, addr2, 0); | |
698 | } | |
699 | ||
700 | static | |
701 | splitit() | |
702 | { | |
703 | register int l; | |
704 | ||
705 | for (l = COLUMNS > 80 ? 40 : COLUMNS / 2; l > 0; l--) | |
706 | putchar('-'); | |
707 | putnl(); | |
708 | } | |
709 | ||
710 | plines(adr1, adr2, movedot) | |
711 | line *adr1; | |
712 | register line *adr2; | |
713 | bool movedot; | |
714 | { | |
715 | register line *addr; | |
716 | ||
717 | pofix(); | |
718 | for (addr = adr1; addr <= adr2; addr++) { | |
719 | getline(*addr); | |
720 | pline(lineno(addr)); | |
721 | if (inopen) | |
722 | putchar('\n' | QUOTE); | |
723 | if (movedot) | |
724 | dot = addr; | |
725 | } | |
726 | } | |
727 | ||
728 | pofix() | |
729 | { | |
730 | ||
731 | if (inopen && Outchar != termchar) { | |
732 | vnfl(); | |
733 | setoutt(); | |
734 | } | |
735 | } | |
736 | ||
737 | /* | |
738 | * Dudley doright to the rescue. | |
739 | * Undo saves the day again. | |
740 | * A tip of the hatlo hat to Warren Teitleman | |
741 | * who made undo as useful as do. | |
742 | * | |
743 | * Command level undo works easily because | |
744 | * the editor has a unique temporary file | |
745 | * index for every line which ever existed. | |
746 | * We don't have to save large blocks of text, | |
747 | * only the indices which are small. We do this | |
748 | * by moving them to after the last line in the | |
749 | * line buffer array, and marking down info | |
750 | * about whence they came. | |
751 | * | |
752 | * Undo is its own inverse. | |
753 | */ | |
754 | undo(c) | |
755 | bool c; | |
756 | { | |
757 | register int i; | |
758 | register line *jp, *kp; | |
759 | line *dolp1, *newdol, *newadot; | |
760 | ||
761 | if (inglobal && inopen <= 0) | |
762 | error("Can't undo in global@commands"); | |
763 | if (!c) | |
764 | somechange(); | |
765 | pkill[0] = pkill[1] = 0; | |
766 | change(); | |
767 | if (undkind == UNDMOVE) { | |
768 | /* | |
769 | * Command to be undone is a move command. | |
770 | * This is handled as a special case by noting that | |
771 | * a move "a,b m c" can be inverted by another move. | |
772 | */ | |
773 | if ((i = (jp = unddel) - undap2) > 0) { | |
774 | /* | |
775 | * when c > b inverse is a+(c-b),c m a-1 | |
776 | */ | |
777 | addr2 = jp; | |
778 | addr1 = (jp = undap1) + i; | |
779 | unddel = jp-1; | |
780 | } else { | |
781 | /* | |
782 | * when b > c inverse is c+1,c+1+(b-a) m b | |
783 | */ | |
784 | addr1 = ++jp; | |
785 | addr2 = jp + ((unddel = undap2) - undap1); | |
786 | } | |
787 | kp = undap1; | |
788 | move1(0, unddel); | |
789 | dot = kp; | |
790 | Command = "move"; | |
791 | killed(); | |
792 | } else { | |
793 | int cnt; | |
794 | ||
795 | newadot = dot; | |
796 | cnt = lineDOL(); | |
797 | newdol = dol; | |
798 | dolp1 = dol + 1; | |
799 | /* | |
800 | * Command to be undone is a non-move. | |
801 | * All such commands are treated as a combination of | |
802 | * a delete command and a append command. | |
803 | * We first move the lines appended by the last command | |
804 | * from undap1 to undap2-1 so that they are just before the | |
805 | * saved deleted lines. | |
806 | */ | |
807 | if ((i = (kp = undap2) - (jp = undap1)) > 0) { | |
808 | if (kp != dolp1) { | |
809 | reverse(jp, kp); | |
810 | reverse(kp, dolp1); | |
811 | reverse(jp, dolp1); | |
812 | } | |
813 | /* | |
814 | * Account for possible backward motion of target | |
815 | * for restoration of saved deleted lines. | |
816 | */ | |
817 | if (unddel >= jp) | |
818 | unddel -= i; | |
819 | newdol -= i; | |
820 | /* | |
821 | * For the case where no lines are restored, dot | |
822 | * is the line before the first line deleted. | |
823 | */ | |
824 | dot = jp-1; | |
825 | } | |
826 | /* | |
827 | * Now put the deleted lines, if any, back where they were. | |
828 | * Basic operation is: dol+1,unddol m unddel | |
829 | */ | |
830 | if (undkind == UNDPUT) { | |
831 | unddel = undap1 - 1; | |
832 | squish(); | |
833 | } | |
834 | jp = unddel + 1; | |
835 | if ((i = (kp = unddol) - dol) > 0) { | |
836 | if (jp != dolp1) { | |
837 | reverse(jp, dolp1); | |
838 | reverse(dolp1, ++kp); | |
839 | reverse(jp, kp); | |
840 | } | |
841 | /* | |
842 | * Account for possible forward motion of the target | |
843 | * for restoration of the deleted lines. | |
844 | */ | |
845 | if (undap1 >= jp) | |
846 | undap1 += i; | |
847 | /* | |
848 | * Dot is the first resurrected line. | |
849 | */ | |
850 | dot = jp; | |
851 | newdol += i; | |
852 | } | |
853 | /* | |
854 | * Clean up so we are invertible | |
855 | */ | |
856 | unddel = undap1 - 1; | |
857 | undap1 = jp; | |
858 | undap2 = jp + i; | |
859 | dol = newdol; | |
860 | netchHAD(cnt); | |
861 | if (undkind == UNDALL) { | |
862 | dot = undadot; | |
863 | undadot = newadot; | |
864 | } | |
865 | undkind = UNDCHANGE; | |
866 | } | |
867 | if (dot == zero && dot != dol) | |
868 | dot = one; | |
869 | } | |
870 | ||
871 | /* | |
872 | * Be (almost completely) sure there really | |
873 | * was a change, before claiming to undo. | |
874 | */ | |
875 | somechange() | |
876 | { | |
877 | register line *ip, *jp; | |
878 | ||
879 | switch (undkind) { | |
880 | ||
881 | case UNDMOVE: | |
882 | return; | |
883 | ||
884 | case UNDCHANGE: | |
885 | if (undap1 == undap2 && dol == unddol) | |
886 | break; | |
887 | return; | |
888 | ||
889 | case UNDPUT: | |
890 | if (undap1 != undap2) | |
891 | return; | |
892 | break; | |
893 | ||
894 | case UNDALL: | |
895 | if (unddol - dol != lineDOL()) | |
896 | return; | |
897 | for (ip = one, jp = dol + 1; ip <= dol; ip++, jp++) | |
898 | if ((*ip &~ 01) != (*jp &~ 01)) | |
899 | return; | |
900 | break; | |
901 | ||
902 | case UNDNONE: | |
903 | error("Nothing to undo"); | |
904 | } | |
905 | error("Nothing changed|Last undoable command didn't change anything"); | |
906 | } |