1 /* $OpenBSD: diff3prog.c,v 1.1 2003/07/10 16:06:07 millert Exp $ */ 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 67 #ifndef lint 68 static const char copyright[] = 69 "@(#) Copyright (c) 1991, 1993\n\ 70 The Regents of the University of California. All rights reserved.\n"; 71 #endif /* not lint */ 72 73 #ifndef lint 74 static const char rcsid[] = "$OpenBSD: diff3prog.c,v 1.1 2003/07/10 16:06:07 millert Exp $"; 75 #endif /* not lint */ 76 77 #include <stdio.h> 78 #include <stdlib.h> 79 #include <ctype.h> 80 #include <err.h> 81 82 /* diff3 - 3-way differential file comparison */ 83 84 /* diff3 [-ex3EX] d13 d23 f1 f2 f3 [m1 m3] 85 * 86 * d13 = diff report on f1 vs f3 87 * d23 = diff report on f2 vs f3 88 * f1, f2, f3 the 3 files 89 * if changes in f1 overlap with changes in f3, m1 and m3 are used 90 * to mark the overlaps; otherwise, the file names f1 and f3 are used 91 * (only for options E and X). 92 */ 93 94 /* 95 * "from" is first in range of changed lines; "to" is last+1 96 * from=to=line after point of insertion for added lines. 97 */ 98 struct range { 99 int from; 100 int to; 101 }; 102 struct diff { 103 struct range old; 104 struct range new; 105 }; 106 107 #define NC 200 108 struct diff d13[NC]; 109 struct diff d23[NC]; 110 /* 111 * "de" is used to gather editing scripts. These are later spewed out in 112 * reverse order. Its first element must be all zero, the "new" component 113 * of "de" contains line positions or byte positions depending on when you 114 * look (!?). Array overlap indicates which sections in "de" correspond to 115 * lines that are different in all three files. 116 */ 117 struct diff de[NC]; 118 char overlap[NC]; 119 int overlapcnt; 120 char line[256]; 121 FILE *fp[3]; 122 int cline[3]; /* # of the last-read line in each file (0-2) */ 123 /* 124 * the latest known correspondence between line numbers of the 3 files 125 * is stored in last[1-3]; 126 */ 127 int last[4]; 128 int eflag; 129 int oflag; /* indicates whether to mark overlaps (-E or -X)*/ 130 int debug = 0; 131 char f1mark[40], f3mark[40]; /* markers for -E and -X */ 132 133 int duplicate(struct range *, struct range *); 134 int edit(struct diff *, int, int); 135 int getchange(FILE *); 136 int getline(FILE *); 137 int number(char **); 138 int readin(char *, struct diff *); 139 int skip(int, int, char *); 140 void change(int, struct range *, int); 141 void keep(int, struct range *); 142 void merge(int, int); 143 void prange(struct range *); 144 void repos(int); 145 void separate(const char *); 146 __dead void edscript(int); 147 __dead void trouble(void); 148 __dead void usage(void); 149 150 int 151 main(int argc, char **argv) 152 { 153 int ch, i, m, n; 154 155 eflag = 0; 156 oflag = 0; 157 while ((ch = getopt(argc, argv, "EeXx3")) != -1) { 158 switch (ch) { 159 case 'E': 160 eflag = 3; 161 oflag = 1; 162 break; 163 case 'e': 164 eflag = 3; 165 break; 166 case 'X': 167 oflag = eflag = 1; 168 break; 169 case 'x': 170 eflag = 1; 171 break; 172 case '3': 173 eflag = 2; 174 break; 175 } 176 } 177 argc -= optind; 178 argv += optind; 179 /* XXX - argc usage seems wrong here */ 180 if (argc < 5) 181 usage(); 182 183 if (oflag) { 184 (void)snprintf(f1mark, sizeof(f1mark), "<<<<<<< %s", 185 argc >= 6 ? argv[5] : argv[2]); 186 (void)snprintf(f3mark, sizeof(f3mark), ">>>>>>> %s", 187 argc >= 7 ? argv[6] : argv[4]); 188 } 189 190 m = readin(argv[0], d13); 191 n = readin(argv[1], d23); 192 for (i = 0; i <= 2; i++) { 193 if ((fp[i] = fopen(argv[i + 2], "r")) == NULL) { 194 printf("diff3: can't open %s\n", argv[i + 2]); 195 exit(EXIT_FAILURE); 196 } 197 } 198 merge(m, n); 199 exit(EXIT_SUCCESS); 200 } 201 202 /* 203 * Pick up the line numbers of allcahnges from one change file. 204 * (This puts the numbers in a vector, which is not strictly necessary, 205 * since the vector is processed in one sequential pass. 206 * The vector could be optimized out of existence) 207 */ 208 int 209 readin(char *name, struct diff *dd) 210 { 211 int i; 212 int a,b,c,d; 213 char kind; 214 char *p; 215 fp[0] = fopen(name, "r"); 216 for (i=0; getchange(fp[0]); i++) { 217 if (i >= NC) 218 err(EXIT_FAILURE, "too many changes"); 219 p = line; 220 a = b = number(&p); 221 if (*p == ',') { 222 p++; 223 b = number(&p); 224 } 225 kind = *p++; 226 c = d = number(&p); 227 if (*p==',') { 228 p++; 229 d = number(&p); 230 } 231 if (kind == 'a') 232 a++; 233 if (kind == 'd') 234 c++; 235 b++; 236 d++; 237 dd[i].old.from = a; 238 dd[i].old.to = b; 239 dd[i].new.from = c; 240 dd[i].new.to = d; 241 } 242 dd[i].old.from = dd[i-1].old.to; 243 dd[i].new.from = dd[i-1].new.to; 244 (void)fclose(fp[0]); 245 return (i); 246 } 247 248 int 249 number(char **lc) 250 { 251 int nn; 252 nn = 0; 253 while (isdigit((unsigned char)(**lc))) 254 nn = nn*10 + *(*lc)++ - '0'; 255 return (nn); 256 } 257 258 int 259 getchange(FILE *b) 260 { 261 while (getline(b)) { 262 if (isdigit((unsigned char)line[0])) 263 return (1); 264 } 265 return (0); 266 } 267 268 int 269 getline(FILE *b) 270 { 271 int i, c; 272 273 for (i = 0; i < sizeof(line) - 1; i++) { 274 c = getc(b); 275 if (c == EOF) 276 break; 277 line[i] = c; 278 if (c == '\n') { 279 line[++i] = 0; 280 return (i); 281 } 282 } 283 return (0); 284 } 285 286 void 287 merge(int m1, int m2) 288 { 289 struct diff *d1, *d2, *d3; 290 int dup, j, t1, t2; 291 292 d1 = d13; 293 d2 = d23; 294 j = 0; 295 while ((t1 = d1 < d13 + m1) | (t2 = d2 < d23 + m2)) { 296 if (debug) { 297 printf("%d,%d=%d,%d %d,%d=%d,%d\n", 298 d1->old.from,d1->old.to, 299 d1->new.from,d1->new.to, 300 d2->old.from,d2->old.to, 301 d2->new.from,d2->new.to); 302 } 303 /* first file is different from others */ 304 if ((!t2 || t1) && d1->new.to < d2->new.from) { 305 /* stuff peculiar to 1st file */ 306 if (eflag==0) { 307 separate("1"); 308 change(1, &d1->old, 0); 309 keep(2, &d1->new); 310 change(3, &d1->new, 0); 311 } 312 d1++; 313 continue; 314 } 315 /* second file is different from others */ 316 if ((!t1 || t2) && d2->new.to < d1->new.from) { 317 if (eflag==0) { 318 separate("2"); 319 keep(1, &d2->new); 320 change(2, &d2->old, 0); 321 change(3, &d2->new, 0); 322 } 323 d2++; 324 continue; 325 } 326 /* 327 * Merge overlapping changes in first file 328 * this happens after extension (see below). 329 */ 330 if (d1 + 1 < d13 + m1 && d1->new.to >= d1[1].new.from) { 331 d1[1].old.from = d1->old.from; 332 d1[1].new.from = d1->new.from; 333 d1++; 334 continue; 335 } 336 337 /* merge overlapping changes in second */ 338 if (d2 + 1 < d23 + m2 && d2->new.to >= d2[1].new.from) { 339 d2[1].old.from = d2->old.from; 340 d2[1].new.from = d2->new.from; 341 d2++; 342 continue; 343 } 344 /* stuff peculiar to third file or different in all */ 345 if (d1->new.from == d2->new.from && d1->new.to == d2->new.to) { 346 dup = duplicate(&d1->old,&d2->old); 347 /* 348 * dup = 0 means all files differ 349 * dup = 1 meands files 1 and 2 identical 350 */ 351 if (eflag==0) { 352 separate(dup ? "3" : ""); 353 change(1, &d1->old, dup); 354 change(2, &d2->old, 0); 355 d3 = d1->old.to > d1->old.from ? d1 : d2; 356 change(3, &d3->new, 0); 357 } else 358 j = edit(d1, dup, j); 359 d1++; 360 d2++; 361 continue; 362 } 363 /* 364 * Overlapping changes from file 1 and 2; extend changes 365 * appropriately to make them coincide. 366 */ 367 if (d1->new.from < d2->new.from) { 368 d2->old.from -= d2->new.from-d1->new.from; 369 d2->new.from = d1->new.from; 370 } else if (d2->new.from < d1->new.from) { 371 d1->old.from -= d1->new.from-d2->new.from; 372 d1->new.from = d2->new.from; 373 } 374 if (d1->new.to > d2->new.to) { 375 d2->old.to += d1->new.to - d2->new.to; 376 d2->new.to = d1->new.to; 377 } else if (d2->new.to > d1->new.to) { 378 d1->old.to += d2->new.to - d1->new.to; 379 d1->new.to = d2->new.to; 380 } 381 } 382 if (eflag) 383 edscript(j); 384 } 385 386 void 387 separate(const char *s) 388 { 389 printf("====%s\n", s); 390 } 391 392 /* 393 * The range of lines rold.from thru rold.to in file i is to be changed. 394 * It is to be printed only if it does not duplicate something to be 395 * printed later. 396 */ 397 void 398 change(int i, struct range *rold, int dup) 399 { 400 printf("%d:", i); 401 last[i] = rold->to; 402 prange(rold); 403 if (dup || debug) 404 return; 405 i--; 406 (void)skip(i, rold->from, NULL); 407 (void)skip(i, rold->to, " "); 408 } 409 410 /* 411 * print the range of line numbers, rold.from thru rold.to, as n1,n2 or n1 412 */ 413 void 414 prange(struct range *rold) 415 { 416 if (rold->to <= rold->from) 417 printf("%da\n", rold->from - 1); 418 else { 419 printf("%d", rold->from); 420 if (rold->to > rold->from+1) 421 printf(",%d", rold->to - 1); 422 printf("c\n"); 423 } 424 } 425 426 /* 427 * No difference was reported by diff between file 1 (or 2) and file 3, 428 * and an artificial dummy difference (trange) must be ginned up to 429 * correspond to the change reported in the other file. 430 */ 431 void 432 keep(int i, struct range *rnew) 433 { 434 int delta; 435 struct range trange; 436 437 delta = last[3] - last[i]; 438 trange.from = rnew->from - delta; 439 trange.to = rnew->to - delta; 440 change(i, &trange, 1); 441 } 442 443 /* 444 * skip to just befor line number from in file "i". If "pr" is non-NULL, 445 * print all skipped stuff with string pr as a prefix. 446 */ 447 int 448 skip(int i, int from, char *pr) 449 { 450 int j, n; 451 452 for (n = 0; cline[i] < from - 1; n += j) { 453 if ((j = getline(fp[i])) == NULL) 454 trouble(); 455 if (pr != NULL) 456 printf("%s%s", pr, line); 457 cline[i]++; 458 } 459 return (n); 460 } 461 462 /* 463 * Return 1 or 0 according as the old range (in file 1) contains exactly 464 * the same data as the new range (in file 2). 465 */ 466 int 467 duplicate(struct range *r1, struct range *r2) 468 { 469 int c,d; 470 int nchar; 471 int nline; 472 473 if (r1->to-r1->from != r2->to-r2->from) 474 return (0); 475 (void)skip(0, r1->from, NULL); 476 (void)skip(1, r2->from, NULL); 477 nchar = 0; 478 for (nline=0; nline < r1->to - r1->from; nline++) { 479 do { 480 c = getc(fp[0]); 481 d = getc(fp[1]); 482 if (c == -1 || d== -1) 483 trouble(); 484 nchar++; 485 if (c != d) { 486 repos(nchar); 487 return (0); 488 } 489 } while (c != '\n'); 490 } 491 repos(nchar); 492 return (1); 493 } 494 495 void 496 repos(int nchar) 497 { 498 int i; 499 500 for (i = 0; i < 2; i++) 501 (void)fseek(fp[i], (long)-nchar, 1); 502 } 503 504 __dead void 505 trouble(void) 506 { 507 errx(EXIT_FAILURE, "logic error"); 508 } 509 510 /* 511 * collect an editing script for later regurgitation 512 */ 513 int 514 edit(struct diff *diff, int dup, int j) 515 { 516 if (((dup + 1) & eflag) == 0) 517 return (j); 518 j++; 519 overlap[j] = !dup; 520 if (!dup) 521 overlapcnt++; 522 de[j].old.from = diff->old.from; 523 de[j].old.to = diff->old.to; 524 de[j].new.from = de[j-1].new.to + skip(2, diff->new.from, NULL); 525 de[j].new.to = de[j].new.from + skip(2, diff->new.to, NULL); 526 return (j); 527 } 528 529 /* regurgitate */ 530 __dead void 531 edscript(int n) 532 { 533 int j,k; 534 char block[BUFSIZ]; 535 536 for (n = n; n > 0; n--) { 537 if (!oflag || !overlap[n]) 538 prange(&de[n].old); 539 else 540 printf("%da\n=======\n", de[n].old.to -1); 541 (void)fseek(fp[2], (long)de[n].new.from, 0); 542 for (k = de[n].new.to-de[n].new.from; k > 0; k-= j) { 543 j = k > BUFSIZ ? BUFSIZ : k; 544 if (fread(block, 1, j, fp[2]) != j) 545 trouble(); 546 (void)fwrite(block, 1, j, stdout); 547 } 548 if (!oflag || !overlap[n]) 549 printf(".\n"); 550 else { 551 printf("%s\n.\n", f3mark); 552 printf("%da\n%s\n.\n", de[n].old.from - 1, f1mark); 553 } 554 } 555 exit(overlapcnt); 556 } 557 558 __dead void 559 usage(void) 560 { 561 extern char *__progname; 562 563 fprintf(stderr, "usage: %s [-exEX3] /tmp/d3a.?????????? " 564 "/tmp/d3b.?????????? file1 file2 file3\n", __progname); 565 exit(EXIT_FAILURE); 566 } 567