Annotation of src/usr.bin/rcs/diff3.c, Revision 1.38
1.38 ! nicm 1: /* $OpenBSD: diff3.c,v 1.37 2015/09/05 09:47:08 jsg Exp $ */
1.1 joris 2:
3: /*
4: * Copyright (C) Caldera International Inc. 2001-2002.
5: * All rights reserved.
6: *
7: * Redistribution and use in source and binary forms, with or without
8: * modification, are permitted provided that the following conditions
9: * are met:
10: * 1. Redistributions of source code and documentation must retain the above
11: * copyright notice, 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: * 3. All advertising materials mentioning features or use of this software
16: * must display the following acknowledgement:
17: * This product includes software developed or owned by Caldera
18: * International, Inc.
19: * 4. Neither the name of Caldera International, Inc. nor the names of other
20: * contributors may be used to endorse or promote products derived from
21: * this software without specific prior written permission.
22: *
23: * USE OF THE SOFTWARE PROVIDED FOR UNDER THIS LICENSE BY CALDERA
24: * INTERNATIONAL, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR
25: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27: * IN NO EVENT SHALL CALDERA INTERNATIONAL, INC. BE LIABLE FOR ANY DIRECT,
28: * INDIRECT INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
29: * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
30: * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
32: * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
33: * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
34: * POSSIBILITY OF SUCH DAMAGE.
35: */
36: /*-
37: * Copyright (c) 1991, 1993
38: * The Regents of the University of California. All rights reserved.
39: *
40: * Redistribution and use in source and binary forms, with or without
41: * modification, are permitted provided that the following conditions
42: * are met:
43: * 1. Redistributions of source code must retain the above copyright
44: * notice, this list of conditions and the following disclaimer.
45: * 2. Redistributions in binary form must reproduce the above copyright
46: * notice, this list of conditions and the following disclaimer in the
47: * documentation and/or other materials provided with the distribution.
48: * 3. Neither the name of the University nor the names of its contributors
49: * may be used to endorse or promote products derived from this software
50: * without specific prior written permission.
51: *
52: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
53: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
54: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
55: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
56: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
57: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
58: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
59: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
60: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
61: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
62: * SUCH DAMAGE.
63: *
64: * @(#)diff3.c 8.1 (Berkeley) 6/6/93
65: */
66:
1.20 xsa 67: #include <ctype.h>
68: #include <err.h>
69: #include <stdio.h>
70: #include <stdlib.h>
71: #include <string.h>
72: #include <unistd.h>
1.1 joris 73:
74: #include "diff.h"
1.4 xsa 75: #include "rcsprog.h"
1.1 joris 76:
77: /* diff3 - 3-way differential file comparison */
78:
79: /* diff3 [-ex3EX] d13 d23 f1 f2 f3 [m1 m3]
80: *
81: * d13 = diff report on f1 vs f3
82: * d23 = diff report on f2 vs f3
83: * f1, f2, f3 the 3 files
84: * if changes in f1 overlap with changes in f3, m1 and m3 are used
85: * to mark the overlaps; otherwise, the file names f1 and f3 are used
86: * (only for options E and X).
87: */
88:
89: /*
90: * "from" is first in range of changed lines; "to" is last+1
91: * from=to=line after point of insertion for added lines.
92: */
93: struct range {
94: int from;
95: int to;
96: };
97:
98: struct diff {
99: struct range old;
100: struct range new;
101: };
102:
103: static size_t szchanges;
104:
105: static struct diff *d13;
106: static struct diff *d23;
107:
108: /*
109: * "de" is used to gather editing scripts. These are later spewed out in
110: * reverse order. Its first element must be all zero, the "new" component
111: * of "de" contains line positions or byte positions depending on when you
112: * look (!?). Array overlap indicates which sections in "de" correspond to
113: * lines that are different in all three files.
114: */
115: static struct diff *de;
116: static char *overlap;
117: static int overlapcnt = 0;
118: static FILE *fp[3];
119: static int cline[3]; /* # of the last-read line in each file (0-2) */
120:
121: /*
122: * the latest known correspondence between line numbers of the 3 files
123: * is stored in last[1-3];
124: */
125: static int last[4];
1.14 xsa 126: static int eflag = 3; /* default -E for compatibility with former RCS */
127: static int oflag = 1; /* default -E for compatibility with former RCS */
1.1 joris 128: static int debug = 0;
1.35 deraadt 129: static char f1mark[PATH_MAX], f3mark[PATH_MAX]; /* markers for -E and -X */
1.1 joris 130:
131: static int duplicate(struct range *, struct range *);
132: static int edit(struct diff *, int, int);
133: static char *getchange(FILE *);
1.33 fgsch 134: static char *get_line(FILE *, size_t *);
1.1 joris 135: static int number(char **);
1.26 tobias 136: static ssize_t readin(char *, struct diff **);
1.1 joris 137: static int skip(int, int, char *);
138: static int edscript(int);
139: static int merge(size_t, size_t);
140: static void change(int, struct range *, int);
141: static void keep(int, struct range *);
142: static void prange(struct range *);
143: static void repos(int);
144: static void separate(const char *);
145: static void increase(void);
146: static int diff3_internal(int, char **, const char *, const char *);
147:
148: int diff3_conflicts = 0;
1.9 xsa 149:
150: /*
151: * For merge(1).
152: */
153: BUF *
154: merge_diff3(char **av, int flags)
155: {
156: int argc;
157: char *argv[5], *dp13, *dp23, *path1, *path2, *path3;
158: BUF *b1, *b2, *b3, *d1, *d2, *diffb;
1.17 niallo 159: u_char *data, *patch;
160: size_t dlen, plen;
1.9 xsa 161:
162: b1 = b2 = b3 = d1 = d2 = diffb = NULL;
163: dp13 = dp23 = path1 = path2 = path3 = NULL;
1.17 niallo 164: data = patch = NULL;
1.9 xsa 165:
1.14 xsa 166: if ((flags & MERGE_EFLAG) && !(flags & MERGE_OFLAG))
167: oflag = 0;
168:
1.31 ray 169: if ((b1 = buf_load(av[0])) == NULL)
1.9 xsa 170: goto out;
1.31 ray 171: if ((b2 = buf_load(av[1])) == NULL)
1.9 xsa 172: goto out;
1.31 ray 173: if ((b3 = buf_load(av[2])) == NULL)
1.9 xsa 174: goto out;
175:
1.31 ray 176: d1 = buf_alloc(128);
177: d2 = buf_alloc(128);
178: diffb = buf_alloc(128);
1.9 xsa 179:
180: (void)xasprintf(&path1, "%s/diff1.XXXXXXXXXX", rcs_tmpdir);
181: (void)xasprintf(&path2, "%s/diff2.XXXXXXXXXX", rcs_tmpdir);
182: (void)xasprintf(&path3, "%s/diff3.XXXXXXXXXX", rcs_tmpdir);
183:
1.30 ray 184: buf_write_stmp(b1, path1);
185: buf_write_stmp(b2, path2);
186: buf_write_stmp(b3, path3);
1.9 xsa 187:
1.30 ray 188: buf_free(b2);
1.9 xsa 189: b2 = NULL;
190:
1.27 ray 191: if ((diffreg(path1, path3, d1, D_FORCEASCII) == D_ERROR) ||
192: (diffreg(path2, path3, d2, D_FORCEASCII) == D_ERROR)) {
1.30 ray 193: buf_free(diffb);
1.9 xsa 194: diffb = NULL;
195: goto out;
196: }
197:
198: (void)xasprintf(&dp13, "%s/d13.XXXXXXXXXX", rcs_tmpdir);
1.30 ray 199: buf_write_stmp(d1, dp13);
1.9 xsa 200:
1.30 ray 201: buf_free(d1);
1.9 xsa 202: d1 = NULL;
203:
204: (void)xasprintf(&dp23, "%s/d23.XXXXXXXXXX", rcs_tmpdir);
1.30 ray 205: buf_write_stmp(d2, dp23);
1.9 xsa 206:
1.30 ray 207: buf_free(d2);
1.9 xsa 208: d2 = NULL;
209:
210: argc = 0;
211: diffbuf = diffb;
212: argv[argc++] = dp13;
213: argv[argc++] = dp23;
214: argv[argc++] = path1;
215: argv[argc++] = path2;
216: argv[argc++] = path3;
217:
218: diff3_conflicts = diff3_internal(argc, argv, av[0], av[2]);
219: if (diff3_conflicts < 0) {
1.30 ray 220: buf_free(diffb);
1.9 xsa 221: diffb = NULL;
222: goto out;
223: }
224:
1.30 ray 225: plen = buf_len(diffb);
226: patch = buf_release(diffb);
227: dlen = buf_len(b1);
228: data = buf_release(b1);
1.17 niallo 229:
230: if ((diffb = rcs_patchfile(data, dlen, patch, plen, ed_patch_lines)) == NULL)
1.9 xsa 231: goto out;
232:
233: if (!(flags & QUIET) && diff3_conflicts != 0)
234: warnx("warning: overlaps or other problems during merge");
235:
236: out:
1.38 ! nicm 237: buf_free(b2);
! 238: buf_free(b3);
! 239: buf_free(d1);
! 240: buf_free(d2);
1.9 xsa 241:
242: (void)unlink(path1);
243: (void)unlink(path2);
244: (void)unlink(path3);
245: (void)unlink(dp13);
246: (void)unlink(dp23);
247:
1.36 nicm 248: free(path1);
249: free(path2);
250: free(path3);
251: free(dp13);
252: free(dp23);
253: free(data);
254: free(patch);
1.9 xsa 255:
256: return (diffb);
257: }
1.1 joris 258:
259: BUF *
1.14 xsa 260: rcs_diff3(RCSFILE *rf, char *workfile, RCSNUM *rev1, RCSNUM *rev2, int flags)
1.1 joris 261: {
262: int argc;
1.22 xsa 263: char *argv[5], r1[RCS_REV_BUFSZ], r2[RCS_REV_BUFSZ];
1.5 xsa 264: char *dp13, *dp23, *path1, *path2, *path3;
1.1 joris 265: BUF *b1, *b2, *b3, *d1, *d2, *diffb;
1.17 niallo 266: size_t dlen, plen;
267: u_char *data, *patch;
1.1 joris 268:
269: b1 = b2 = b3 = d1 = d2 = diffb = NULL;
1.7 xsa 270: dp13 = dp23 = path1 = path2 = path3 = NULL;
1.17 niallo 271: data = patch = NULL;
1.1 joris 272:
1.14 xsa 273: if ((flags & MERGE_EFLAG) && !(flags & MERGE_OFLAG))
274: oflag = 0;
275:
1.1 joris 276: rcsnum_tostr(rev1, r1, sizeof(r1));
277: rcsnum_tostr(rev2, r2, sizeof(r2));
278:
1.31 ray 279: if ((b1 = buf_load(workfile)) == NULL)
1.1 joris 280: goto out;
281:
1.14 xsa 282: if (!(flags & QUIET))
1.6 xsa 283: (void)fprintf(stderr, "retrieving revision %s\n", r1);
1.1 joris 284: if ((b2 = rcs_getrev(rf, rev1)) == NULL)
285: goto out;
286:
1.14 xsa 287: if (!(flags & QUIET))
1.6 xsa 288: (void)fprintf(stderr, "retrieving revision %s\n", r2);
1.1 joris 289: if ((b3 = rcs_getrev(rf, rev2)) == NULL)
290: goto out;
291:
1.31 ray 292: d1 = buf_alloc(128);
293: d2 = buf_alloc(128);
294: diffb = buf_alloc(128);
1.1 joris 295:
1.5 xsa 296: (void)xasprintf(&path1, "%s/diff1.XXXXXXXXXX", rcs_tmpdir);
297: (void)xasprintf(&path2, "%s/diff2.XXXXXXXXXX", rcs_tmpdir);
298: (void)xasprintf(&path3, "%s/diff3.XXXXXXXXXX", rcs_tmpdir);
1.3 ray 299:
1.30 ray 300: buf_write_stmp(b1, path1);
301: buf_write_stmp(b2, path2);
302: buf_write_stmp(b3, path3);
1.1 joris 303:
1.30 ray 304: buf_free(b2);
1.1 joris 305: b2 = NULL;
306:
1.27 ray 307: if ((diffreg(path1, path3, d1, D_FORCEASCII) == D_ERROR) ||
308: (diffreg(path2, path3, d2, D_FORCEASCII) == D_ERROR)) {
1.30 ray 309: buf_free(diffb);
1.7 xsa 310: diffb = NULL;
311: goto out;
312: }
1.1 joris 313:
1.5 xsa 314: (void)xasprintf(&dp13, "%s/d13.XXXXXXXXXX", rcs_tmpdir);
1.30 ray 315: buf_write_stmp(d1, dp13);
1.1 joris 316:
1.30 ray 317: buf_free(d1);
1.1 joris 318: d1 = NULL;
319:
1.5 xsa 320: (void)xasprintf(&dp23, "%s/d23.XXXXXXXXXX", rcs_tmpdir);
1.30 ray 321: buf_write_stmp(d2, dp23);
1.1 joris 322:
1.30 ray 323: buf_free(d2);
1.1 joris 324: d2 = NULL;
325:
326: argc = 0;
327: diffbuf = diffb;
328: argv[argc++] = dp13;
329: argv[argc++] = dp23;
330: argv[argc++] = path1;
331: argv[argc++] = path2;
332: argv[argc++] = path3;
333:
334: diff3_conflicts = diff3_internal(argc, argv, workfile, r2);
335: if (diff3_conflicts < 0) {
1.30 ray 336: buf_free(diffb);
1.1 joris 337: diffb = NULL;
338: goto out;
339: }
340:
1.30 ray 341: plen = buf_len(diffb);
342: patch = buf_release(diffb);
343: dlen = buf_len(b1);
344: data = buf_release(b1);
1.17 niallo 345:
346: if ((diffb = rcs_patchfile(data, dlen, patch, plen, ed_patch_lines)) == NULL)
1.1 joris 347: goto out;
348:
1.14 xsa 349: if (!(flags & QUIET) && diff3_conflicts != 0)
1.6 xsa 350: warnx("warning: overlaps or other problems during merge");
1.1 joris 351:
352: out:
1.38 ! nicm 353: buf_free(b2);
! 354: buf_free(b3);
! 355: buf_free(d1);
! 356: buf_free(d2);
1.1 joris 357:
358: (void)unlink(path1);
359: (void)unlink(path2);
360: (void)unlink(path3);
361: (void)unlink(dp13);
362: (void)unlink(dp23);
1.5 xsa 363:
1.36 nicm 364: free(path1);
365: free(path2);
366: free(path3);
367: free(dp13);
368: free(dp23);
369: free(data);
370: free(patch);
1.1 joris 371:
372: return (diffb);
373: }
374:
375: static int
376: diff3_internal(int argc, char **argv, const char *fmark, const char *rmark)
377: {
1.26 tobias 378: ssize_t m, n;
1.1 joris 379: int i;
380:
381: if (argc < 5)
382: return (-1);
383:
1.14 xsa 384: if (oflag) {
385: i = snprintf(f1mark, sizeof(f1mark), "<<<<<<< %s", fmark);
1.19 xsa 386: if (i < 0 || i >= (int)sizeof(f1mark))
1.14 xsa 387: errx(1, "diff3_internal: string truncated");
388:
389: i = snprintf(f3mark, sizeof(f3mark), ">>>>>>> %s", rmark);
1.19 xsa 390: if (i < 0 || i >= (int)sizeof(f3mark))
1.14 xsa 391: errx(1, "diff3_internal: string truncated");
392: }
1.1 joris 393:
394: increase();
1.26 tobias 395: if ((m = readin(argv[0], &d13)) < 0) {
396: warn("%s", argv[0]);
397: return (-1);
398: }
399: if ((n = readin(argv[1], &d23)) < 0) {
400: warn("%s", argv[1]);
401: return (-1);
402: }
1.1 joris 403:
1.3 ray 404: for (i = 0; i <= 2; i++)
1.1 joris 405: if ((fp[i] = fopen(argv[i + 2], "r")) == NULL) {
406: warn("%s", argv[i + 2]);
407: return (-1);
408: }
409:
410: return (merge(m, n));
411: }
412:
413: int
414: ed_patch_lines(struct rcs_lines *dlines, struct rcs_lines *plines)
415: {
416: char op, *ep;
1.13 espie 417: struct rcs_line *sort, *lp, *dlp, *ndlp, *insert_after;
1.1 joris 418: int start, end, i, lineno;
1.17 niallo 419: u_char tmp;
1.1 joris 420:
421: dlp = TAILQ_FIRST(&(dlines->l_lines));
422: lp = TAILQ_FIRST(&(plines->l_lines));
423:
424: end = 0;
425: for (lp = TAILQ_NEXT(lp, l_list); lp != NULL;
426: lp = TAILQ_NEXT(lp, l_list)) {
1.17 niallo 427: /* Skip blank lines */
428: if (lp->l_len < 2)
429: continue;
1.30 ray 430:
1.17 niallo 431: /* NUL-terminate line buffer for strtol() safety. */
432: tmp = lp->l_line[lp->l_len - 1];
433: lp->l_line[lp->l_len - 1] = '\0';
1.30 ray 434:
1.17 niallo 435: /* len - 1 is NUL terminator so we use len - 2 for 'op' */
436: op = lp->l_line[lp->l_len - 2];
1.1 joris 437: start = (int)strtol(lp->l_line, &ep, 10);
1.30 ray 438:
1.17 niallo 439: /* Restore the last byte of the buffer */
440: lp->l_line[lp->l_len - 1] = tmp;
1.30 ray 441:
1.1 joris 442: if (op == 'a') {
443: if (start > dlines->l_nblines ||
444: start < 0 || *ep != 'a')
445: errx(1, "ed_patch_lines");
446: } else if (op == 'c') {
447: if (start > dlines->l_nblines ||
448: start < 0 || (*ep != ',' && *ep != 'c'))
449: errx(1, "ed_patch_lines");
450:
451: if (*ep == ',') {
452: ep++;
453: end = (int)strtol(ep, &ep, 10);
454: if (end < 0 || *ep != 'c')
455: errx(1, "ed_patch_lines");
456: } else {
457: end = start;
458: }
459: }
460:
461:
462: for (;;) {
463: if (dlp == NULL)
464: break;
465: if (dlp->l_lineno == start)
466: break;
467: if (dlp->l_lineno > start) {
1.29 ray 468: dlp = TAILQ_PREV(dlp, tqh, l_list);
1.1 joris 469: } else if (dlp->l_lineno < start) {
470: ndlp = TAILQ_NEXT(dlp, l_list);
471: if (ndlp->l_lineno > start)
472: break;
473: dlp = ndlp;
474: }
475: }
476:
477: if (dlp == NULL)
478: errx(1, "ed_patch_lines");
479:
480:
481: if (op == 'c') {
1.29 ray 482: insert_after = TAILQ_PREV(dlp, tqh, l_list);
1.1 joris 483: for (i = 0; i <= (end - start); i++) {
484: ndlp = TAILQ_NEXT(dlp, l_list);
485: TAILQ_REMOVE(&(dlines->l_lines), dlp, l_list);
486: dlp = ndlp;
487: }
1.13 espie 488: dlp = insert_after;
1.1 joris 489: }
490:
491: if (op == 'a' || op == 'c') {
492: for (;;) {
493: ndlp = lp;
494: lp = TAILQ_NEXT(lp, l_list);
495: if (lp == NULL)
496: errx(1, "ed_patch_lines");
497:
1.17 niallo 498: if (!memcmp(lp->l_line, ".", 1))
1.1 joris 499: break;
500:
501: TAILQ_REMOVE(&(plines->l_lines), lp, l_list);
502: TAILQ_INSERT_AFTER(&(dlines->l_lines), dlp,
503: lp, l_list);
504: dlp = lp;
505:
506: lp->l_lineno = start;
507: lp = ndlp;
508: }
509: }
510:
511: /*
512: * always resort lines as the markers might be put at the
513: * same line as we first started editing.
514: */
515: lineno = 0;
516: TAILQ_FOREACH(sort, &(dlines->l_lines), l_list)
517: sort->l_lineno = lineno++;
518: dlines->l_nblines = lineno - 1;
519: }
520:
521: return (0);
522: }
523:
524: /*
525: * Pick up the line numbers of all changes from one change file.
526: * (This puts the numbers in a vector, which is not strictly necessary,
527: * since the vector is processed in one sequential pass.
528: * The vector could be optimized out of existence)
529: */
1.26 tobias 530: static ssize_t
1.1 joris 531: readin(char *name, struct diff **dd)
532: {
533: int a, b, c, d;
534: char kind, *p;
535: size_t i;
536:
537: fp[0] = fopen(name, "r");
1.26 tobias 538: if (fp[0] == NULL)
539: return (-1);
1.1 joris 540: for (i = 0; (p = getchange(fp[0])); i++) {
541: if (i >= szchanges - 1)
542: increase();
543: a = b = number(&p);
544: if (*p == ',') {
545: p++;
546: b = number(&p);
547: }
548: kind = *p++;
549: c = d = number(&p);
550: if (*p==',') {
551: p++;
552: d = number(&p);
553: }
554: if (kind == 'a')
555: a++;
556: if (kind == 'd')
557: c++;
558: b++;
559: d++;
560: (*dd)[i].old.from = a;
561: (*dd)[i].old.to = b;
562: (*dd)[i].new.from = c;
563: (*dd)[i].new.to = d;
564: }
565:
566: if (i) {
567: (*dd)[i].old.from = (*dd)[i-1].old.to;
568: (*dd)[i].new.from = (*dd)[i-1].new.to;
569: }
1.30 ray 570:
1.1 joris 571: (void)fclose(fp[0]);
572:
573: return (i);
574: }
575:
576: static int
577: number(char **lc)
578: {
579: int nn;
580:
581: nn = 0;
582: while (isdigit((unsigned char)(**lc)))
583: nn = nn*10 + *(*lc)++ - '0';
584:
585: return (nn);
586: }
587:
588: static char *
589: getchange(FILE *b)
590: {
591: char *line;
592:
1.33 fgsch 593: while ((line = get_line(b, NULL))) {
1.1 joris 594: if (isdigit((unsigned char)line[0]))
595: return (line);
596: }
597:
598: return (NULL);
599: }
600:
601: static char *
1.33 fgsch 602: get_line(FILE *b, size_t *n)
1.1 joris 603: {
604: char *cp;
605: size_t len;
606: static char *buf;
607: static size_t bufsize;
608:
609: if ((cp = fgetln(b, &len)) == NULL)
610: return (NULL);
611:
612: if (cp[len - 1] != '\n')
613: len++;
614: if (len + 1 > bufsize) {
615: do {
616: bufsize += 1024;
617: } while (len + 1 > bufsize);
1.34 deraadt 618: buf = xreallocarray(buf, 1, bufsize);
1.1 joris 619: }
620: memcpy(buf, cp, len - 1);
621: buf[len - 1] = '\n';
622: buf[len] = '\0';
623: if (n != NULL)
624: *n = len;
625:
626: return (buf);
627: }
628:
629: static int
630: merge(size_t m1, size_t m2)
631: {
632: struct diff *d1, *d2, *d3;
633: int dpl, j, t1, t2;
634:
635: d1 = d13;
636: d2 = d23;
637: j = 0;
1.37 jsg 638: while ((t1 = (d1 < d13 + m1)) | (t2 = (d2 < d23 + m2))) {
1.1 joris 639: if (debug) {
640: printf("%d,%d=%d,%d %d,%d=%d,%d\n",
641: d1->old.from, d1->old.to,
642: d1->new.from, d1->new.to,
643: d2->old.from, d2->old.to,
644: d2->new.from, d2->new.to);
645: }
646:
647: /* first file is different from others */
648: if (!t2 || (t1 && d1->new.to < d2->new.from)) {
649: /* stuff peculiar to 1st file */
650: if (eflag==0) {
651: separate("1");
652: change(1, &d1->old, 0);
653: keep(2, &d1->new);
654: change(3, &d1->new, 0);
655: }
656: d1++;
657: continue;
658: }
659:
660: /* second file is different from others */
661: if (!t1 || (t2 && d2->new.to < d1->new.from)) {
662: if (eflag==0) {
663: separate("2");
664: keep(1, &d2->new);
665: change(2, &d2->old, 0);
666: change(3, &d2->new, 0);
667: }
668: d2++;
669: continue;
670: }
671:
672: /*
673: * Merge overlapping changes in first file
674: * this happens after extension (see below).
675: */
676: if (d1 + 1 < d13 + m1 && d1->new.to >= d1[1].new.from) {
677: d1[1].old.from = d1->old.from;
678: d1[1].new.from = d1->new.from;
679: d1++;
680: continue;
681: }
682:
683: /* merge overlapping changes in second */
684: if (d2 + 1 < d23 + m2 && d2->new.to >= d2[1].new.from) {
685: d2[1].old.from = d2->old.from;
686: d2[1].new.from = d2->new.from;
687: d2++;
688: continue;
689: }
690: /* stuff peculiar to third file or different in all */
691: if (d1->new.from == d2->new.from && d1->new.to == d2->new.to) {
692: dpl = duplicate(&d1->old,&d2->old);
693: if (dpl == -1)
694: return (-1);
695:
696: /*
697: * dpl = 0 means all files differ
698: * dpl = 1 means files 1 and 2 identical
699: */
700: if (eflag==0) {
701: separate(dpl ? "3" : "");
702: change(1, &d1->old, dpl);
703: change(2, &d2->old, 0);
704: d3 = d1->old.to > d1->old.from ? d1 : d2;
705: change(3, &d3->new, 0);
706: } else
707: j = edit(d1, dpl, j);
708: d1++;
709: d2++;
710: continue;
711: }
712:
713: /*
714: * Overlapping changes from file 1 and 2; extend changes
715: * appropriately to make them coincide.
716: */
717: if (d1->new.from < d2->new.from) {
718: d2->old.from -= d2->new.from-d1->new.from;
719: d2->new.from = d1->new.from;
720: } else if (d2->new.from < d1->new.from) {
721: d1->old.from -= d1->new.from-d2->new.from;
722: d1->new.from = d2->new.from;
723: }
724: if (d1->new.to > d2->new.to) {
725: d2->old.to += d1->new.to - d2->new.to;
726: d2->new.to = d1->new.to;
727: } else if (d2->new.to > d1->new.to) {
728: d1->old.to += d2->new.to - d1->new.to;
729: d1->new.to = d2->new.to;
730: }
731: }
732:
733: return (edscript(j));
734: }
735:
736: static void
737: separate(const char *s)
738: {
739: diff_output("====%s\n", s);
740: }
741:
742: /*
743: * The range of lines rold.from thru rold.to in file i is to be changed.
744: * It is to be printed only if it does not duplicate something to be
745: * printed later.
746: */
747: static void
748: change(int i, struct range *rold, int fdup)
749: {
750: diff_output("%d:", i);
751: last[i] = rold->to;
752: prange(rold);
753: if (fdup || debug)
754: return;
755: i--;
756: (void)skip(i, rold->from, NULL);
757: (void)skip(i, rold->to, " ");
758: }
759:
760: /*
761: * print the range of line numbers, rold.from thru rold.to, as n1,n2 or n1
762: */
763: static void
764: prange(struct range *rold)
765: {
766: if (rold->to <= rold->from)
767: diff_output("%da\n", rold->from - 1);
768: else {
769: diff_output("%d", rold->from);
770: if (rold->to > rold->from+1)
771: diff_output(",%d", rold->to - 1);
772: diff_output("c\n");
773: }
774: }
775:
776: /*
777: * No difference was reported by diff between file 1 (or 2) and file 3,
778: * and an artificial dummy difference (trange) must be ginned up to
779: * correspond to the change reported in the other file.
780: */
781: static void
782: keep(int i, struct range *rnew)
783: {
784: int delta;
785: struct range trange;
786:
787: delta = last[3] - last[i];
788: trange.from = rnew->from - delta;
789: trange.to = rnew->to - delta;
790: change(i, &trange, 1);
791: }
792:
793: /*
794: * skip to just before line number from in file "i". If "pr" is non-NULL,
795: * print all skipped stuff with string pr as a prefix.
796: */
797: static int
798: skip(int i, int from, char *pr)
799: {
800: size_t j, n;
801: char *line;
802:
803: for (n = 0; cline[i] < from - 1; n += j) {
1.33 fgsch 804: if ((line = get_line(fp[i], &j)) == NULL)
1.1 joris 805: return (-1);
806: if (pr != NULL)
807: diff_output("%s%s", pr, line);
808: cline[i]++;
809: }
810: return ((int) n);
811: }
812:
813: /*
814: * Return 1 or 0 according as the old range (in file 1) contains exactly
815: * the same data as the new range (in file 2).
816: */
817: static int
818: duplicate(struct range *r1, struct range *r2)
819: {
820: int c,d;
821: int nchar;
822: int nline;
823:
824: if (r1->to-r1->from != r2->to-r2->from)
825: return (0);
826: (void)skip(0, r1->from, NULL);
827: (void)skip(1, r2->from, NULL);
828: nchar = 0;
829: for (nline=0; nline < r1->to - r1->from; nline++) {
830: do {
831: c = getc(fp[0]);
832: d = getc(fp[1]);
833: if (c == -1 || d== -1)
834: return (-1);
835: nchar++;
836: if (c != d) {
837: repos(nchar);
838: return (0);
839: }
840: } while (c != '\n');
841: }
842: repos(nchar);
843: return (1);
844: }
845:
846: static void
847: repos(int nchar)
848: {
849: int i;
850:
851: for (i = 0; i < 2; i++)
1.24 tobias 852: (void)fseek(fp[i], (long)-nchar, SEEK_CUR);
1.1 joris 853: }
854:
855: /*
856: * collect an editing script for later regurgitation
857: */
858: static int
859: edit(struct diff *diff, int fdup, int j)
860: {
861: if (((fdup + 1) & eflag) == 0)
862: return (j);
863: j++;
864: overlap[j] = !fdup;
865: if (!fdup)
866: overlapcnt++;
867: de[j].old.from = diff->old.from;
868: de[j].old.to = diff->old.to;
869: de[j].new.from = de[j-1].new.to + skip(2, diff->new.from, NULL);
870: de[j].new.to = de[j].new.from + skip(2, diff->new.to, NULL);
871: return (j);
872: }
873:
874: /* regurgitate */
875: static int
876: edscript(int n)
877: {
878: int j, k;
879: char block[BUFSIZ+1];
880:
1.32 nicm 881: for (; n > 0; n--) {
1.1 joris 882: if (!oflag || !overlap[n])
883: prange(&de[n].old);
884: else
885: diff_output("%da\n=======\n", de[n].old.to -1);
1.24 tobias 886: (void)fseek(fp[2], (long)de[n].new.from, SEEK_SET);
1.1 joris 887: for (k = de[n].new.to-de[n].new.from; k > 0; k-= j) {
888: j = k > BUFSIZ ? BUFSIZ : k;
1.30 ray 889: if (fread(block, 1, j, fp[2]) != j)
1.1 joris 890: return (-1);
891: block[j] = '\0';
892: diff_output("%s", block);
893: }
894:
895: if (!oflag || !overlap[n])
896: diff_output(".\n");
897: else {
898: diff_output("%s\n.\n", f3mark);
899: diff_output("%da\n%s\n.\n", de[n].old.from - 1, f1mark);
900: }
901: }
902:
903: return (overlapcnt);
904: }
905:
906: static void
907: increase(void)
908: {
909: size_t newsz, incr;
910:
911: /* are the memset(3) calls needed? */
912: newsz = szchanges == 0 ? 64 : 2 * szchanges;
913: incr = newsz - szchanges;
914:
1.34 deraadt 915: d13 = xreallocarray(d13, newsz, sizeof(*d13));
1.21 ray 916: memset(d13 + szchanges, 0, incr * sizeof(*d13));
1.34 deraadt 917: d23 = xreallocarray(d23, newsz, sizeof(*d23));
1.21 ray 918: memset(d23 + szchanges, 0, incr * sizeof(*d23));
1.34 deraadt 919: de = xreallocarray(de, newsz, sizeof(*de));
1.21 ray 920: memset(de + szchanges, 0, incr * sizeof(*de));
1.34 deraadt 921: overlap = xreallocarray(overlap, newsz, sizeof(*overlap));
1.21 ray 922: memset(overlap + szchanges, 0, incr * sizeof(*overlap));
1.1 joris 923: szchanges = newsz;
924: }
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