usr.bin/patch/patch.c

   1 /*
   2  * $OpenBSD: patch.c,v 1.43 2004/11/19 20:08:11 otto Exp $
   3  * $DragonFly: src/usr.bin/patch/patch.c,v 1.4 2005/01/10 21:45:33 swildner Exp $
   4  */
   5
   6 /*
   7  * patch - a program to apply diffs to original files
   8  *
   9  * Copyright 1986, Larry Wall
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following condition is met:
  13  * 1. Redistributions of source code must retain the above copyright notice,
  14  * this condition and the following disclaimer.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
  17  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  18  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  19  * 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 OR
  22  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  23  * 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  * -C option added in 1998, original code by Marc Espie, based on FreeBSD
  29  * behaviour
  30  */
  31
  32 #include <sys/types.h>
  33 #include <sys/stat.h>
  34
  35 #include <ctype.h>
  36 #include <getopt.h>
  37 #include <limits.h>
  38 #include <stdio.h>
  39 #include <string.h>
  40 #include <stdlib.h>
  41 #include <unistd.h>
  42
  43 #include "common.h"
  44 #include "util.h"
  45 #include "pch.h"
  46 #include "inp.h"
  47 #include "backupfile.h"
  48 #include "pathnames.h"
  49
  50 int             filemode = 0644;
  51
  52 char            buf[MAXLINELEN];        /* general purpose buffer */
  53
  54 bool            using_plan_a = true;    /* try to keep everything in memory */
  55 bool            out_of_mem = false;     /* ran out of memory in plan a */
  56
  57 #define MAXFILEC 2
  58
  59 char            *filearg[MAXFILEC];
  60 bool            ok_to_create_file = false;
  61 char            *outname = NULL;
  62 char            *origprae = NULL;
  63 char            *TMPOUTNAME;
  64 char            *TMPINNAME;
  65 char            *TMPREJNAME;
  66 char            *TMPPATNAME;
  67 bool            toutkeep = false;
  68 bool            trejkeep = false;
  69 bool            warn_on_invalid_line;
  70 bool            last_line_missing_eol;
  71
  72 #ifdef DEBUGGING
  73 int             debug = 0;
  74 #endif
  75
  76 bool            force = false;
  77 bool            batch = false;
  78 bool            verbose = true;
  79 bool            reverse = false;
  80 bool            noreverse = false;
  81 bool            skip_rest_of_patch = false;
  82 int             strippath = 957;
  83 bool            canonicalize = false;
  84 bool            check_only = false;
  85 int             diff_type = 0;
  86 char            *revision = NULL;       /* prerequisite revision, if any */
  87 LINENUM         input_lines = 0;        /* how long is input file in lines */
  88 int             posix = 0;              /* strict POSIX mode? */
  89
  90 static void     reinitialize_almost_everything(void);
  91 static void     get_some_switches(void);
  92 static LINENUM  locate_hunk(LINENUM);
  93 static void     abort_context_hunk(void);
  94 static void     rej_line(int, LINENUM);
  95 static void     abort_hunk(void);
  96 static void     apply_hunk(LINENUM);
  97 static void     init_output(const char *);
  98 static void     init_reject(const char *);
  99 static void     copy_till(LINENUM, bool);
 100 static void     spew_output(void);
 101 static void     dump_line(LINENUM, bool);
 102 static bool     patch_match(LINENUM, LINENUM, LINENUM);
 103 static bool     similar(const char *, const char *, int);
 104 static void     usage(void);
 105
 106 /* true if -E was specified on command line.  */
 107 static bool     remove_empty_files = false;
 108
 109 /* true if -R was specified on command line.  */
 110 static bool     reverse_flag_specified = false;
 111
 112 /* buffer holding the name of the rejected patch file. */
 113 static char     rejname[NAME_MAX + 1];
 114
 115 /* buffer for stderr */
 116 static char     serrbuf[BUFSIZ];
 117
 118 /* how many input lines have been irretractibly output */
 119 static LINENUM  last_frozen_line = 0;
 120
 121 static int      Argc;           /* guess */
 122 static char     **Argv;
 123 static int      Argc_last;      /* for restarting plan_b */
 124 static char     **Argv_last;
 125
 126 static FILE     *ofp = NULL;    /* output file pointer */
 127 static FILE     *rejfp = NULL;  /* reject file pointer */
 128
 129 static int      filec = 0;      /* how many file arguments? */
 130 static LINENUM  last_offset = 0;
 131 static LINENUM  maxfuzz = 2;
 132
 133 /* patch using ifdef, ifndef, etc. */
 134 static bool             do_defines = false;
 135 /* #ifdef xyzzy */
 136 static char             if_defined[128];
 137 /* #ifndef xyzzy */
 138 static char             not_defined[128];
 139 /* #else */
 140 static const char       else_defined[] = "#else\n";
 141 /* #endif xyzzy */
 142 static char             end_defined[128];
 143
 144
 145 /* Apply a set of diffs as appropriate. */
 146
 147 int
 148 main(int argc, char *argv[])
 149 {
 150         int     error = 0, hunk, failed, i, fd;
 151         LINENUM where = 0, newwhere, fuzz, mymaxfuzz;
 152         const   char *tmpdir;
 153         char    *v;
 154
 155         setbuf(stderr, serrbuf);
 156         for (i = 0; i < MAXFILEC; i++)
 157                 filearg[i] = NULL;
 158
 159         /* Cons up the names of the temporary files.  */
 160         if ((tmpdir = getenv("TMPDIR")) == NULL || *tmpdir == '\0')
 161                 tmpdir = _PATH_TMP;
 162         for (i = strlen(tmpdir) - 1; i > 0 && tmpdir[i] == '/'; i--)
 163                 ;
 164         i++;
 165         if (asprintf(&TMPOUTNAME, "%.*s/patchoXXXXXXXXXX", i, tmpdir) == -1)
 166                 fatal("cannot allocate memory");
 167         if ((fd = mkstemp(TMPOUTNAME)) < 0)
 168                 pfatal("can't create %s", TMPOUTNAME);
 169         close(fd);
 170
 171         if (asprintf(&TMPINNAME, "%.*s/patchiXXXXXXXXXX", i, tmpdir) == -1)
 172                 fatal("cannot allocate memory");
 173         if ((fd = mkstemp(TMPINNAME)) < 0)
 174                 pfatal("can't create %s", TMPINNAME);
 175         close(fd);
 176
 177         if (asprintf(&TMPREJNAME, "%.*s/patchrXXXXXXXXXX", i, tmpdir) == -1)
 178                 fatal("cannot allocate memory");
 179         if ((fd = mkstemp(TMPREJNAME)) < 0)
 180                 pfatal("can't create %s", TMPREJNAME);
 181         close(fd);
 182
 183         if (asprintf(&TMPPATNAME, "%.*s/patchpXXXXXXXXXX", i, tmpdir) == -1)
 184                 fatal("cannot allocate memory");
 185         if ((fd = mkstemp(TMPPATNAME)) < 0)
 186                 pfatal("can't create %s", TMPPATNAME);
 187         close(fd);
 188
 189         v = getenv("SIMPLE_BACKUP_SUFFIX");
 190         if (v)
 191                 simple_backup_suffix = v;
 192         else
 193                 simple_backup_suffix = ORIGEXT;
 194
 195         /* parse switches */
 196         Argc = argc;
 197         Argv = argv;
 198         get_some_switches();
 199
 200         if (backup_type == none) {
 201                 if ((v = getenv("PATCH_VERSION_CONTROL")) == NULL)
 202                         v = getenv("VERSION_CONTROL");
 203                 if (v != NULL || !posix)
 204                         backup_type = get_version(v);   /* OK to pass NULL. */
 205         }
 206
 207         /* make sure we clean up /tmp in case of disaster */
 208         set_signals(0);
 209
 210         for (open_patch_file(filearg[1]); there_is_another_patch();
 211             reinitialize_almost_everything()) {
 212                 /* for each patch in patch file */
 213
 214                 warn_on_invalid_line = true;
 215
 216                 if (outname == NULL)
 217                         outname = savestr(filearg[0]);
 218
 219                 /* for ed script just up and do it and exit */
 220                 if (diff_type == ED_DIFF) {
 221                         do_ed_script();
 222                         continue;
 223                 }
 224                 /* initialize the patched file */
 225                 if (!skip_rest_of_patch)
 226                         init_output(TMPOUTNAME);
 227
 228                 /* initialize reject file */
 229                 init_reject(TMPREJNAME);
 230
 231                 /* find out where all the lines are */
 232                 if (!skip_rest_of_patch)
 233                         scan_input(filearg[0]);
 234
 235                 /* from here on, open no standard i/o files, because malloc */
 236                 /* might misfire and we can't catch it easily */
 237
 238                 /* apply each hunk of patch */
 239                 hunk = 0;
 240                 failed = 0;
 241                 out_of_mem = false;
 242                 while (another_hunk()) {
 243                         hunk++;
 244                         fuzz = 0;
 245                         mymaxfuzz = pch_context();
 246                         if (maxfuzz < mymaxfuzz)
 247                                 mymaxfuzz = maxfuzz;
 248                         if (!skip_rest_of_patch) {
 249                                 do {
 250                                         where = locate_hunk(fuzz);
 251                                         if (hunk == 1 && where == 0 && !force) {
 252                                                 /* dwim for reversed patch? */
 253                                                 if (!pch_swap()) {
 254                                                         if (fuzz == 0)
 255                                                                 say("Not enough memory to try swapped hunk!  Assuming unswapped.\n");
 256                                                         continue;
 257                                                 }
 258                                                 reverse = !reverse;
 259                                                 /* try again */
 260                                                 where = locate_hunk(fuzz);
 261                                                 if (where == 0) {
 262                                                         /* didn't find it swapped */
 263                                                         if (!pch_swap())
 264                                                                 /* put it back to normal */
 265                                                                 fatal("lost hunk on alloc error!\n");
 266                                                         reverse = !reverse;
 267                                                 } else if (noreverse) {
 268                                                         if (!pch_swap())
 269                                                                 /* put it back to normal */
 270                                                                 fatal("lost hunk on alloc error!\n");
 271                                                         reverse = !reverse;
 272                                                         say("Ignoring previously applied (or reversed) patch.\n");
 273                                                         skip_rest_of_patch = true;
 274                                                 } else if (batch) {
 275                                                         if (verbose)
 276                                                                 say("%seversed (or previously applied) patch detected!  %s -R.",
 277                                                                     reverse ? "R" : "Unr",
 278                                                                     reverse ? "Assuming" : "Ignoring");
 279                                                 } else {
 280                                                         ask("%seversed (or previously applied) patch detected!  %s -R? [y] ",
 281                                                             reverse ? "R" : "Unr",
 282                                                             reverse ? "Assume" : "Ignore");
 283                                                         if (*buf == 'n') {
 284                                                                 ask("Apply anyway? [n] ");
 285                                                                 if (*buf != 'y')
 286                                                                         skip_rest_of_patch = true;
 287                                                                 where = 0;
 288                                                                 reverse = !reverse;
 289                                                                 if (!pch_swap())
 290                                                                         /* put it back to normal */
 291                                                                         fatal("lost hunk on alloc error!\n");
 292                                                         }
 293                                                 }
 294                                         }
 295                                 } while (!skip_rest_of_patch && where == 0 &&
 296                                     ++fuzz <= mymaxfuzz);
 297
 298                                 if (skip_rest_of_patch) {       /* just got decided */
 299                                         fclose(ofp);
 300                                         ofp = NULL;
 301                                 }
 302                         }
 303                         newwhere = pch_newfirst() + last_offset;
 304                         if (skip_rest_of_patch) {
 305                                 abort_hunk();
 306                                 failed++;
 307                                 if (verbose)
 308                                         say("Hunk #%d ignored at %ld.\n",
 309                                             hunk, newwhere);
 310                         } else if (where == 0) {
 311                                 abort_hunk();
 312                                 failed++;
 313                                 if (verbose)
 314                                         say("Hunk #%d failed at %ld.\n",
 315                                             hunk, newwhere);
 316                         } else {
 317                                 apply_hunk(where);
 318                                 if (verbose) {
 319                                         say("Hunk #%d succeeded at %ld",
 320                                             hunk, newwhere);
 321                                         if (fuzz != 0)
 322                                                 say(" with fuzz %ld", fuzz);
 323                                         if (last_offset)
 324                                                 say(" (offset %ld line%s)",
 325                                                     last_offset,
 326                                                     last_offset == 1L ? "" : "s");
 327                                         say(".\n");
 328                                 }
 329                         }
 330                 }
 331
 332                 if (out_of_mem && using_plan_a) {
 333                         Argc = Argc_last;
 334                         Argv = Argv_last;
 335                         say("\n\nRan out of memory using Plan A--trying again...\n\n");
 336                         if (ofp)
 337                                 fclose(ofp);
 338                         ofp = NULL;
 339                         if (rejfp)
 340                                 fclose(rejfp);
 341                         rejfp = NULL;
 342                         continue;
 343                 }
 344                 if (hunk == 0)
 345                         fatal("Internal error: hunk should not be 0\n");
 346
 347                 /* finish spewing out the new file */
 348                 if (!skip_rest_of_patch)
 349                         spew_output();
 350
 351                 /* and put the output where desired */
 352                 ignore_signals();
 353                 if (!skip_rest_of_patch) {
 354                         struct stat     statbuf;
 355                         char    *realout = outname;
 356
 357                         if (!check_only) {
 358                                 if (move_file(TMPOUTNAME, outname) < 0) {
 359                                         toutkeep = true;
 360                                         realout = TMPOUTNAME;
 361                                         chmod(TMPOUTNAME, filemode);
 362                                 } else
 363                                         chmod(outname, filemode);
 364
 365                                 if (remove_empty_files &&
 366                                     stat(realout, &statbuf) == 0 &&
 367                                     statbuf.st_size == 0) {
 368                                         if (verbose)
 369                                                 say("Removing %s (empty after patching).\n",
 370                                                     realout);
 371                                         unlink(realout);
 372                                 }
 373                         }
 374                 }
 375                 fclose(rejfp);
 376                 rejfp = NULL;
 377                 if (failed) {
 378                         error = 1;
 379                         if (*rejname == '\0') {
 380                                 if (strlcpy(rejname, outname,
 381                                     sizeof(rejname)) >= sizeof(rejname))
 382                                         fatal("filename %s is too long\n", outname);
 383                                 if (strlcat(rejname, REJEXT,
 384                                     sizeof(rejname)) >= sizeof(rejname))
 385                                         fatal("filename %s is too long\n", outname);
 386                         }
 387                         if (skip_rest_of_patch) {
 388                                 say("%d out of %d hunks ignored--saving rejects to %s\n",
 389                                     failed, hunk, rejname);
 390                         } else {
 391                                 say("%d out of %d hunks failed--saving rejects to %s\n",
 392                                     failed, hunk, rejname);
 393                         }
 394                         if (!check_only && move_file(TMPREJNAME, rejname) < 0)
 395                                 trejkeep = true;
 396                 }
 397                 set_signals(1);
 398         }
 399         my_exit(error);
 400         /* NOTREACHED */
 401 }
 402
 403 /* Prepare to find the next patch to do in the patch file. */
 404
 405 static void
 406 reinitialize_almost_everything(void)
 407 {
 408         re_patch();
 409         re_input();
 410
 411         input_lines = 0;
 412         last_frozen_line = 0;
 413
 414         filec = 0;
 415         if (!out_of_mem) {
 416                 free(filearg[0]);
 417                 filearg[0] = NULL;
 418         }
 419
 420         free(outname);
 421         outname = NULL;
 422
 423         last_offset = 0;
 424         diff_type = 0;
 425
 426         free(revision);
 427         revision = NULL;
 428
 429         reverse = reverse_flag_specified;
 430         skip_rest_of_patch = false;
 431
 432         get_some_switches();
 433 }
 434
 435 /* Process switches and filenames. */
 436
 437 static void
 438 get_some_switches(void)
 439 {
 440         const char *options = "b::B:cCd:D:eEfF:i:lnNo:p:r:RstuvV:x:z:";
 441         static struct option longopts[] = {
 442                 {"backup",              no_argument,            0,      'b'},
 443                 {"batch",               no_argument,            0,      't'},
 444                 {"check",               no_argument,            0,      'C'},
 445                 {"context",             no_argument,            0,      'c'},
 446                 {"debug",               required_argument,      0,      'x'},
 447                 {"directory",           required_argument,      0,      'd'},
 448                 {"ed",                  no_argument,            0,      'e'},
 449                 {"force",               no_argument,            0,      'f'},
 450                 {"forward",             no_argument,            0,      'N'},
 451                 {"fuzz",                required_argument,      0,      'F'},
 452                 {"ifdef",               required_argument,      0,      'D'},
 453                 {"input",               required_argument,      0,      'i'},
 454                 {"ignore-whitespace",   no_argument,            0,      'l'},
 455                 {"normal",              no_argument,            0,      'n'},
 456                 {"output",              required_argument,      0,      'o'},
 457                 {"prefix",              required_argument,      0,      'B'},
 458                 {"quiet",               no_argument,            0,      's'},
 459                 {"reject-file",         required_argument,      0,      'r'},
 460                 {"remove-empty-files",  no_argument,            0,      'E'},
 461                 {"reverse",             no_argument,            0,      'R'},
 462                 {"silent",              no_argument,            0,      's'},
 463                 {"strip",               required_argument,      0,      'p'},
 464                 {"suffix",              required_argument,      0,      'z'},
 465                 {"unified",             no_argument,            0,      'u'},
 466                 {"version",             no_argument,            0,      'v'},
 467                 {"version-control",     required_argument,      0,      'V'},
 468                 {"posix",               no_argument,            &posix, 1},
 469                 {NULL,                  0,                      0,      0}
 470         };
 471         int ch;
 472
 473         rejname[0] = '\0';
 474         Argc_last = Argc;
 475         Argv_last = Argv;
 476         if (!Argc)
 477                 return;
 478         optreset = optind = 1;
 479         while ((ch = getopt_long(Argc, Argv, options, longopts, NULL)) != -1) {
 480                 switch (ch) {
 481                 case 'b':
 482                         if (backup_type == none)
 483                                 backup_type = numbered_existing;
 484                         if (optarg == NULL)
 485                                 break;
 486                         if (verbose)
 487                                 say("Warning, the ``-b suffix'' option has been"
 488                                     " obsoleted by the -z option.\n");
 489                         /* FALLTHROUGH */
 490                 case 'z':
 491                         /* must directly follow 'b' case for backwards compat */
 492                         simple_backup_suffix = savestr(optarg);
 493                         break;
 494                 case 'B':
 495                         origprae = savestr(optarg);
 496                         break;
 497                 case 'c':
 498                         diff_type = CONTEXT_DIFF;
 499                         break;
 500                 case 'C':
 501                         check_only = true;
 502                         break;
 503                 case 'd':
 504                         if (chdir(optarg) < 0)
 505                                 pfatal("can't cd to %s", optarg);
 506                         break;
 507                 case 'D':
 508                         do_defines = true;
 509                         if (!isalpha(*optarg) && *optarg != '_')
 510                                 fatal("argument to -D is not an identifier\n");
 511                         snprintf(if_defined, sizeof if_defined,
 512                             "#ifdef %s\n", optarg);
 513                         snprintf(not_defined, sizeof not_defined,
 514                             "#ifndef %s\n", optarg);
 515                         snprintf(end_defined, sizeof end_defined,
 516                             "#endif /* %s */\n", optarg);
 517                         break;
 518                 case 'e':
 519                         diff_type = ED_DIFF;
 520                         break;
 521                 case 'E':
 522                         remove_empty_files = true;
 523                         break;
 524                 case 'f':
 525                         force = true;
 526                         break;
 527                 case 'F':
 528                         maxfuzz = atoi(optarg);
 529                         break;
 530                 case 'i':
 531                         if (++filec == MAXFILEC)
 532                                 fatal("too many file arguments\n");
 533                         filearg[filec] = savestr(optarg);
 534                         break;
 535                 case 'l':
 536                         canonicalize = true;
 537                         break;
 538                 case 'n':
 539                         diff_type = NORMAL_DIFF;
 540                         break;
 541                 case 'N':
 542                         noreverse = true;
 543                         break;
 544                 case 'o':
 545                         outname = savestr(optarg);
 546                         break;
 547                 case 'p':
 548                         strippath = atoi(optarg);
 549                         break;
 550                 case 'r':
 551                         if (strlcpy(rejname, optarg,
 552                             sizeof(rejname)) >= sizeof(rejname))
 553                                 fatal("argument for -r is too long\n");
 554                         break;
 555                 case 'R':
 556                         reverse = true;
 557                         reverse_flag_specified = true;
 558                         break;
 559                 case 's':
 560                         verbose = false;
 561                         break;
 562                 case 't':
 563                         batch = true;
 564                         break;
 565                 case 'u':
 566                         diff_type = UNI_DIFF;
 567                         break;
 568                 case 'v':
 569                         version();
 570                         break;
 571                 case 'V':
 572                         backup_type = get_version(optarg);
 573                         break;
 574 #ifdef DEBUGGING
 575                 case 'x':
 576                         debug = atoi(optarg);
 577                         break;
 578 #endif
 579                 default:
 580                         if (ch != '\0')
 581                                 usage();
 582                         break;
 583                 }
 584         }
 585         Argc -= optind;
 586         Argv += optind;
 587
 588         if (Argc > 0) {
 589                 filearg[0] = savestr(*Argv++);
 590                 Argc--;
 591                 while (Argc > 0) {
 592                         if (++filec == MAXFILEC)
 593                                 fatal("too many file arguments\n");
 594                         filearg[filec] = savestr(*Argv++);
 595                         Argc--;
 596                 }
 597         }
 598
 599         if (getenv("POSIXLY_CORRECT") != NULL)
 600                 posix = 1;
 601 }
 602
 603 static void
 604 usage(void)
 605 {
 606         fprintf(stderr,
 607 "usage: patch [-bcCeEflnNRstuv] [-B backup-prefix] [-d directory] [-D symbol]\n"
 608 "             [-F max-fuzz] [-i patchfile] [-o out-file] [-p strip-count]\n"
 609 "             [-r rej-name] [-V {numbered,existing,simple}] [-z backup-ext]\n"
 610 "             [origfile [patchfile]]\n");
 611         my_exit(EXIT_SUCCESS);
 612 }
 613
 614 /*
 615  * Attempt to find the right place to apply this hunk of patch.
 616  */
 617 static LINENUM
 618 locate_hunk(LINENUM fuzz)
 619 {
 620         LINENUM first_guess = pch_first() + last_offset;
 621         LINENUM offset;
 622         LINENUM pat_lines = pch_ptrn_lines();
 623         LINENUM max_pos_offset = input_lines - first_guess - pat_lines + 1;
 624         LINENUM max_neg_offset = first_guess - last_frozen_line - 1 + pch_context();
 625
 626         if (pat_lines == 0) {           /* null range matches always */
 627                 if (verbose && fuzz == 0 && (diff_type == CONTEXT_DIFF
 628                     || diff_type == NEW_CONTEXT_DIFF
 629                     || diff_type == UNI_DIFF)) {
 630                         say("Empty context always matches.\n");
 631                 }
 632                 if (diff_type == CONTEXT_DIFF
 633                     || diff_type == NEW_CONTEXT_DIFF
 634                     || diff_type == UNI_DIFF) {
 635                         if (fuzz == 0)
 636                                 return (input_lines == 0 ? first_guess : 0);
 637                 } else
 638                         return (first_guess);
 639         }
 640         if (max_neg_offset >= first_guess)      /* do not try lines < 0 */
 641                 max_neg_offset = first_guess - 1;
 642         if (first_guess <= input_lines && patch_match(first_guess, 0, fuzz))
 643                 return first_guess;
 644         for (offset = 1; ; offset++) {
 645                 bool    check_after = (offset <= max_pos_offset);
 646                 bool    check_before = (offset <= max_neg_offset);
 647
 648                 if (check_after && patch_match(first_guess, offset, fuzz)) {
 649 #ifdef DEBUGGING
 650                         if (debug & 1)
 651                                 say("Offset changing from %ld to %ld\n",
 652                                     last_offset, offset);
 653 #endif
 654                         last_offset = offset;
 655                         return first_guess + offset;
 656                 } else if (check_before && patch_match(first_guess, -offset, fuzz)) {
 657 #ifdef DEBUGGING
 658                         if (debug & 1)
 659                                 say("Offset changing from %ld to %ld\n",
 660                                     last_offset, -offset);
 661 #endif
 662                         last_offset = -offset;
 663                         return first_guess - offset;
 664                 } else if (!check_before && !check_after)
 665                         return 0;
 666         }
 667 }
 668
 669 /* We did not find the pattern, dump out the hunk so they can handle it. */
 670
 671 static void
 672 abort_context_hunk(void)
 673 {
 674         LINENUM i;
 675         const LINENUM   pat_end = pch_end();
 676         /*
 677          * add in last_offset to guess the same as the previous successful
 678          * hunk
 679          */
 680         const LINENUM   oldfirst = pch_first() + last_offset;
 681         const LINENUM   newfirst = pch_newfirst() + last_offset;
 682         const LINENUM   oldlast = oldfirst + pch_ptrn_lines() - 1;
 683         const LINENUM   newlast = newfirst + pch_repl_lines() - 1;
 684         const char      *stars = (diff_type >= NEW_CONTEXT_DIFF ? " ****" : "");
 685         const char      *minuses = (diff_type >= NEW_CONTEXT_DIFF ? " ----" : " -----");
 686
 687         fprintf(rejfp, "***************\n");
 688         for (i = 0; i <= pat_end; i++) {
 689                 switch (pch_char(i)) {
 690                 case '*':
 691                         if (oldlast < oldfirst)
 692                                 fprintf(rejfp, "*** 0%s\n", stars);
 693                         else if (oldlast == oldfirst)
 694                                 fprintf(rejfp, "*** %ld%s\n", oldfirst, stars);
 695                         else
 696                                 fprintf(rejfp, "*** %ld,%ld%s\n", oldfirst,
 697                                     oldlast, stars);
 698                         break;
 699                 case '=':
 700                         if (newlast < newfirst)
 701                                 fprintf(rejfp, "--- 0%s\n", minuses);
 702                         else if (newlast == newfirst)
 703                                 fprintf(rejfp, "--- %ld%s\n", newfirst, minuses);
 704                         else
 705                                 fprintf(rejfp, "--- %ld,%ld%s\n", newfirst,
 706                                     newlast, minuses);
 707                         break;
 708                 case '\n':
 709                         fprintf(rejfp, "%s", pfetch(i));
 710                         break;
 711                 case ' ':
 712                 case '-':
 713                 case '+':
 714                 case '!':
 715                         fprintf(rejfp, "%c %s", pch_char(i), pfetch(i));
 716                         break;
 717                 default:
 718                         fatal("fatal internal error in abort_context_hunk\n");
 719                 }
 720         }
 721 }
 722
 723 static void
 724 rej_line(int ch, LINENUM i)
 725 {
 726         size_t len;
 727         const char *line = pfetch(i);
 728
 729         len = strlen(line);
 730
 731         fprintf(rejfp, "%c%s", ch, line);
 732         if (len == 0 || line[len-1] != '\n')
 733                 fprintf(rejfp, "\n\\ No newline at end of file\n");
 734 }
 735
 736 static void
 737 abort_hunk(void)
 738 {
 739         LINENUM         i, j, split;
 740         int             ch1, ch2;
 741         const LINENUM   pat_end = pch_end();
 742         const LINENUM   oldfirst = pch_first() + last_offset;
 743         const LINENUM   newfirst = pch_newfirst() + last_offset;
 744
 745         if (diff_type != UNI_DIFF) {
 746                 abort_context_hunk();
 747                 return;
 748         }
 749         split = -1;
 750         for (i = 0; i <= pat_end; i++) {
 751                 if (pch_char(i) == '=') {
 752                         split = i;
 753                         break;
 754                 }
 755         }
 756         if (split == -1) {
 757                 fprintf(rejfp, "malformed hunk: no split found\n");
 758                 return;
 759         }
 760         i = 0;
 761         j = split + 1;
 762         fprintf(rejfp, "@@ -%ld,%ld +%ld,%ld @@\n",
 763             pch_ptrn_lines() ? oldfirst : 0,
 764             pch_ptrn_lines(), newfirst, pch_repl_lines());
 765         while (i < split || j <= pat_end) {
 766                 ch1 = i < split ? pch_char(i) : -1;
 767                 ch2 = j <= pat_end ? pch_char(j) : -1;
 768                 if (ch1 == '-') {
 769                         rej_line('-', i);
 770                         i++;
 771                 } else if (ch1 == ' ' && ch2 == ' ') {
 772                         rej_line(' ', i);
 773                         i++;
 774                         j++;
 775                 } else if (ch1 == '!' && ch2 == '!') {
 776                         while (i < split && ch1 == '!') {
 777                                 rej_line('-', i);
 778                                 i++;
 779                                 ch1 = i < split ? pch_char(i) : -1;
 780                         }
 781                         while (j <= pat_end && ch2 == '!') {
 782                                 rej_line('+', j);
 783                                 j++;
 784                                 ch2 = j <= pat_end ? pch_char(j) : -1;
 785                         }
 786                 } else if (ch1 == '*') {
 787                         i++;
 788                 } else if (ch2 == '+' || ch2 == ' ') {
 789                         rej_line(ch2, j);
 790                         j++;
 791                 } else {
 792                         fprintf(rejfp, "internal error on (%ld %ld %ld)\n",
 793                             i, split, j);
 794                         rej_line(ch1, i);
 795                         rej_line(ch2, j);
 796                         return;
 797                 }
 798         }
 799 }
 800
 801 /* We found where to apply it (we hope), so do it. */
 802
 803 static void
 804 apply_hunk(LINENUM where)
 805 {
 806         LINENUM         old = 1;
 807         const LINENUM   lastline = pch_ptrn_lines();
 808         LINENUM         new = lastline + 1;
 809 #define OUTSIDE 0
 810 #define IN_IFNDEF 1
 811 #define IN_IFDEF 2
 812 #define IN_ELSE 3
 813         int             def_state = OUTSIDE;
 814         const LINENUM   pat_end = pch_end();
 815
 816         where--;
 817         while (pch_char(new) == '=' || pch_char(new) == '\n')
 818                 new++;
 819
 820         while (old <= lastline) {
 821                 if (pch_char(old) == '-') {
 822                         copy_till(where + old - 1, false);
 823                         if (do_defines) {
 824                                 if (def_state == OUTSIDE) {
 825                                         fputs(not_defined, ofp);
 826                                         def_state = IN_IFNDEF;
 827                                 } else if (def_state == IN_IFDEF) {
 828                                         fputs(else_defined, ofp);
 829                                         def_state = IN_ELSE;
 830                                 }
 831                                 fputs(pfetch(old), ofp);
 832                         }
 833                         last_frozen_line++;
 834                         old++;
 835                 } else if (new > pat_end) {
 836                         break;
 837                 } else if (pch_char(new) == '+') {
 838                         copy_till(where + old - 1, false);
 839                         if (do_defines) {
 840                                 if (def_state == IN_IFNDEF) {
 841                                         fputs(else_defined, ofp);
 842                                         def_state = IN_ELSE;
 843                                 } else if (def_state == OUTSIDE) {
 844                                         fputs(if_defined, ofp);
 845                                         def_state = IN_IFDEF;
 846                                 }
 847                         }
 848                         fputs(pfetch(new), ofp);
 849                         new++;
 850                 } else if (pch_char(new) != pch_char(old)) {
 851                         say("Out-of-sync patch, lines %ld,%ld--mangled text or line numbers, maybe?\n",
 852                             pch_hunk_beg() + old,
 853                             pch_hunk_beg() + new);
 854 #ifdef DEBUGGING
 855                         say("oldchar = '%c', newchar = '%c'\n",
 856                             pch_char(old), pch_char(new));
 857 #endif
 858                         my_exit(2);
 859                 } else if (pch_char(new) == '!') {
 860                         copy_till(where + old - 1, false);
 861                         if (do_defines) {
 862                                 fputs(not_defined, ofp);
 863                                 def_state = IN_IFNDEF;
 864                         }
 865                         while (pch_char(old) == '!') {
 866                                 if (do_defines) {
 867                                         fputs(pfetch(old), ofp);
 868                                 }
 869                                 last_frozen_line++;
 870                                 old++;
 871                         }
 872                         if (do_defines) {
 873                                 fputs(else_defined, ofp);
 874                                 def_state = IN_ELSE;
 875                         }
 876                         while (pch_char(new) == '!') {
 877                                 fputs(pfetch(new), ofp);
 878                                 new++;
 879                         }
 880                 } else {
 881                         if (pch_char(new) != ' ')
 882                                 fatal("Internal error: expected ' '\n");
 883                         old++;
 884                         new++;
 885                         if (do_defines && def_state != OUTSIDE) {
 886                                 fputs(end_defined, ofp);
 887                                 def_state = OUTSIDE;
 888                         }
 889                 }
 890         }
 891         if (new <= pat_end && pch_char(new) == '+') {
 892                 copy_till(where + old - 1, false);
 893                 if (do_defines) {
 894                         if (def_state == OUTSIDE) {
 895                                 fputs(if_defined, ofp);
 896                                 def_state = IN_IFDEF;
 897                         } else if (def_state == IN_IFNDEF) {
 898                                 fputs(else_defined, ofp);
 899                                 def_state = IN_ELSE;
 900                         }
 901                 }
 902                 while (new <= pat_end && pch_char(new) == '+') {
 903                         fputs(pfetch(new), ofp);
 904                         new++;
 905                 }
 906         }
 907         if (do_defines && def_state != OUTSIDE) {
 908                 fputs(end_defined, ofp);
 909         }
 910 }
 911
 912 /*
 913  * Open the new file.
 914  */
 915 static void
 916 init_output(const char *name)
 917 {
 918         ofp = fopen(name, "w");
 919         if (ofp == NULL)
 920                 pfatal("can't create %s", name);
 921 }
 922
 923 /*
 924  * Open a file to put hunks we can't locate.
 925  */
 926 static void
 927 init_reject(const char *name)
 928 {
 929         rejfp = fopen(name, "w");
 930         if (rejfp == NULL)
 931                 pfatal("can't create %s", name);
 932 }
 933
 934 /*
 935  * Copy input file to output, up to wherever hunk is to be applied.
 936  * If endoffile is true, treat the last line specially since it may
 937  * lack a newline.
 938  */
 939 static void
 940 copy_till(LINENUM lastline, bool endoffile)
 941 {
 942         if (last_frozen_line > lastline)
 943                 fatal("misordered hunks! output would be garbled\n");
 944         while (last_frozen_line < lastline) {
 945                 if (++last_frozen_line == lastline && endoffile)
 946                         dump_line(last_frozen_line, !last_line_missing_eol);
 947                 else
 948                         dump_line(last_frozen_line, true);
 949         }
 950 }
 951
 952 /*
 953  * Finish copying the input file to the output file.
 954  */
 955 static void
 956 spew_output(void)
 957 {
 958 #ifdef DEBUGGING
 959         if (debug & 256)
 960                 say("il=%ld lfl=%ld\n", input_lines, last_frozen_line);
 961 #endif
 962         if (input_lines)
 963                 copy_till(input_lines, true);   /* dump remainder of file */
 964         fclose(ofp);
 965         ofp = NULL;
 966 }
 967
 968 /*
 969  * Copy one line from input to output.
 970  */
 971 static void
 972 dump_line(LINENUM line, bool write_newline)
 973 {
 974         char    *s;
 975
 976         s = ifetch(line, 0);
 977         if (s == NULL)
 978                 return;
 979         /* Note: string is not NUL terminated. */
 980         for (; *s != '\n'; s++)
 981                 putc(*s, ofp);
 982         if (write_newline)
 983                 putc('\n', ofp);
 984 }
 985
 986 /*
 987  * Does the patch pattern match at line base+offset?
 988  */
 989 static bool
 990 patch_match(LINENUM base, LINENUM offset, LINENUM fuzz)
 991 {
 992         LINENUM         pline = 1 + fuzz;
 993         LINENUM         iline;
 994         LINENUM         pat_lines = pch_ptrn_lines() - fuzz;
 995         const char      *ilineptr;
 996         const char      *plineptr;
 997         short           plinelen;
 998
 999         for (iline = base + offset + fuzz; pline <= pat_lines; pline++, iline++) {
1000                 ilineptr = ifetch(iline, offset >= 0);
1001                 if (ilineptr == NULL)
1002                         return false;
1003                 plineptr = pfetch(pline);
1004                 plinelen = pch_line_len(pline);
1005                 if (canonicalize) {
1006                         if (!similar(ilineptr, plineptr, plinelen))
1007                                 return false;
1008                 } else if (strnNE(ilineptr, plineptr, plinelen))
1009                         return false;
1010                 if (iline == input_lines) {
1011                         /*
1012                          * We are looking at the last line of the file.
1013                          * If the file has no eol, the patch line should
1014                          * not have one either and vice-versa. Note that
1015                          * plinelen > 0.
1016                          */
1017                         if (last_line_missing_eol) {
1018                                 if (plineptr[plinelen - 1] == '\n')
1019                                         return false;
1020                         } else {
1021                                 if (plineptr[plinelen - 1] != '\n')
1022                                         return false;
1023                         }
1024                 }
1025         }
1026         return true;
1027 }
1028
1029 /*
1030  * Do two lines match with canonicalized white space?
1031  */
1032 static bool
1033 similar(const char *a, const char *b, int len)
1034 {
1035         while (len) {
1036                 if (isspace(*b)) {      /* whitespace (or \n) to match? */
1037                         if (!isspace(*a))       /* no corresponding whitespace? */
1038                                 return false;
1039                         while (len && isspace(*b) && *b != '\n')
1040                                 b++, len--;     /* skip pattern whitespace */
1041                         while (isspace(*a) && *a != '\n')
1042                                 a++;    /* skip target whitespace */
1043                         if (*a == '\n' || *b == '\n')
1044                                 return (*a == *b);      /* should end in sync */
1045                 } else if (*a++ != *b++)        /* match non-whitespace chars */
1046                         return false;
1047                 else
1048                         len--;  /* probably not necessary */
1049         }
1050         return true;            /* actually, this is not reached */
1051         /* since there is always a \n */
1052 }