usr.bin/patch/patch.c

   1 /*
   2  * $OpenBSD: patch.c,v 1.45 2007/04/18 21:52:24 sobrado Exp $
   3  * $DragonFly: src/usr.bin/patch/patch.c,v 1.8 2008/08/10 23:01:51 joerg 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 mode_t          filemode = 0644;
  51
  52 char            buf[MAXLINELEN];        /* general purpose buffer */
  53 size_t          buf_len = sizeof(buf);
  54
  55 bool            using_plan_a = true;    /* try to keep everything in memory */
  56 bool            out_of_mem = false;     /* ran out of memory in plan a */
  57
  58 #define MAXFILEC 2
  59
  60 char            *filearg[MAXFILEC];
  61 bool            ok_to_create_file = false;
  62 char            *outname = NULL;
  63 char            *origprae = NULL;
  64 char            *TMPOUTNAME;
  65 char            *TMPINNAME;
  66 char            *TMPREJNAME;
  67 char            *TMPPATNAME;
  68 bool            toutkeep = false;
  69 bool            trejkeep = false;
  70 bool            warn_on_invalid_line;
  71 bool            last_line_missing_eol;
  72
  73 #ifdef DEBUGGING
  74 int             debug = 0;
  75 #endif
  76
  77 bool            force = false;
  78 bool            batch = false;
  79 bool            verbose = true;
  80 bool            reverse = false;
  81 bool            noreverse = false;
  82 bool            skip_rest_of_patch = false;
  83 int             strippath = 957;
  84 bool            canonicalize = false;
  85 bool            check_only = false;
  86 int             diff_type = 0;
  87 char            *revision = NULL;       /* prerequisite revision, if any */
  88 LINENUM         input_lines = 0;        /* how long is input file in lines */
  89 int             posix = 0;              /* strict POSIX mode? */
  90
  91 static void     reinitialize_almost_everything(void);
  92 static void     get_some_switches(void);
  93 static LINENUM  locate_hunk(LINENUM);
  94 static void     abort_context_hunk(void);
  95 static void     rej_line(int, LINENUM);
  96 static void     abort_hunk(void);
  97 static void     apply_hunk(LINENUM);
  98 static void     init_output(const char *);
  99 static void     init_reject(const char *);
 100 static void     copy_till(LINENUM, bool);
 101 static void     spew_output(void);
 102 static void     dump_line(LINENUM, bool);
 103 static bool     patch_match(LINENUM, LINENUM, LINENUM);
 104 static bool     similar(const char *, const char *, int);
 105 static void     usage(void);
 106
 107 /* true if -E was specified on command line.  */
 108 static bool     remove_empty_files = false;
 109
 110 /* true if -R was specified on command line.  */
 111 static bool     reverse_flag_specified = false;
 112
 113 /* buffer holding the name of the rejected patch file. */
 114 static char     rejname[NAME_MAX + 1];
 115
 116 /* buffer for stderr */
 117 static char     serrbuf[BUFSIZ];
 118
 119 /* how many input lines have been irretractibly output */
 120 static LINENUM  last_frozen_line = 0;
 121
 122 static int      Argc;           /* guess */
 123 static char     **Argv;
 124 static int      Argc_last;      /* for restarting plan_b */
 125 static char     **Argv_last;
 126
 127 static FILE     *ofp = NULL;    /* output file pointer */
 128 static FILE     *rejfp = NULL;  /* reject file pointer */
 129
 130 static int      filec = 0;      /* how many file arguments? */
 131 static LINENUM  last_offset = 0;
 132 static LINENUM  maxfuzz = 2;
 133
 134 /* patch using ifdef, ifndef, etc. */
 135 static bool             do_defines = false;
 136 /* #ifdef xyzzy */
 137 static char             if_defined[128];
 138 /* #ifndef xyzzy */
 139 static char             not_defined[128];
 140 /* #else */
 141 static const char       else_defined[] = "#else\n";
 142 /* #endif xyzzy */
 143 static char             end_defined[128];
 144
 145
 146 /* Apply a set of diffs as appropriate. */
 147
 148 int
 149 main(int argc, char *argv[])
 150 {
 151         int     error = 0, hunk, failed, i, fd;
 152         LINENUM where = 0, newwhere, fuzz, mymaxfuzz;
 153         const   char *tmpdir;
 154         char    *v;
 155
 156         setbuf(stderr, serrbuf);
 157         for (i = 0; i < MAXFILEC; i++)
 158                 filearg[i] = NULL;
 159
 160         /* Cons up the names of the temporary files.  */
 161         if ((tmpdir = getenv("TMPDIR")) == NULL || *tmpdir == '\0')
 162                 tmpdir = _PATH_TMP;
 163         for (i = strlen(tmpdir) - 1; i > 0 && tmpdir[i] == '/'; i--)
 164                 ;
 165         i++;
 166         if (asprintf(&TMPOUTNAME, "%.*s/patchoXXXXXXXXXX", i, tmpdir) == -1)
 167                 fatal("cannot allocate memory");
 168         if ((fd = mkstemp(TMPOUTNAME)) < 0)
 169                 pfatal("can't create %s", TMPOUTNAME);
 170         close(fd);
 171
 172         if (asprintf(&TMPINNAME, "%.*s/patchiXXXXXXXXXX", i, tmpdir) == -1)
 173                 fatal("cannot allocate memory");
 174         if ((fd = mkstemp(TMPINNAME)) < 0)
 175                 pfatal("can't create %s", TMPINNAME);
 176         close(fd);
 177
 178         if (asprintf(&TMPREJNAME, "%.*s/patchrXXXXXXXXXX", i, tmpdir) == -1)
 179                 fatal("cannot allocate memory");
 180         if ((fd = mkstemp(TMPREJNAME)) < 0)
 181                 pfatal("can't create %s", TMPREJNAME);
 182         close(fd);
 183
 184         if (asprintf(&TMPPATNAME, "%.*s/patchpXXXXXXXXXX", i, tmpdir) == -1)
 185                 fatal("cannot allocate memory");
 186         if ((fd = mkstemp(TMPPATNAME)) < 0)
 187                 pfatal("can't create %s", TMPPATNAME);
 188         close(fd);
 189
 190         v = getenv("SIMPLE_BACKUP_SUFFIX");
 191         if (v)
 192                 simple_backup_suffix = v;
 193         else
 194                 simple_backup_suffix = ORIGEXT;
 195
 196         /* parse switches */
 197         Argc = argc;
 198         Argv = argv;
 199         get_some_switches();
 200
 201         if (backup_type == none) {
 202                 if ((v = getenv("PATCH_VERSION_CONTROL")) == NULL)
 203                         v = getenv("VERSION_CONTROL");
 204                 if (v != NULL || !posix)
 205                         backup_type = get_version(v);   /* OK to pass NULL. */
 206         }
 207
 208         /* make sure we clean up /tmp in case of disaster */
 209         set_signals(0);
 210
 211         for (open_patch_file(filearg[1]); there_is_another_patch();
 212             reinitialize_almost_everything()) {
 213                 /* for each patch in patch file */
 214
 215                 warn_on_invalid_line = true;
 216
 217                 if (outname == NULL)
 218                         outname = savestr(filearg[0]);
 219
 220                 /* for ed script just up and do it and exit */
 221                 if (diff_type == ED_DIFF) {
 222                         do_ed_script();
 223                         continue;
 224                 }
 225                 /* initialize the patched file */
 226                 if (!skip_rest_of_patch)
 227                         init_output(TMPOUTNAME);
 228
 229                 /* initialize reject file */
 230                 init_reject(TMPREJNAME);
 231
 232                 /* find out where all the lines are */
 233                 if (!skip_rest_of_patch)
 234                         scan_input(filearg[0]);
 235
 236                 /* from here on, open no standard i/o files, because malloc */
 237                 /* might misfire and we can't catch it easily */
 238
 239                 /* apply each hunk of patch */
 240                 hunk = 0;
 241                 failed = 0;
 242                 out_of_mem = false;
 243                 while (another_hunk()) {
 244                         hunk++;
 245                         fuzz = 0;
 246                         mymaxfuzz = pch_context();
 247                         if (maxfuzz < mymaxfuzz)
 248                                 mymaxfuzz = maxfuzz;
 249                         if (!skip_rest_of_patch) {
 250                                 do {
 251                                         where = locate_hunk(fuzz);
 252                                         if (hunk == 1 && where == 0 && !force) {
 253                                                 /* dwim for reversed patch? */
 254                                                 if (!pch_swap()) {
 255                                                         if (fuzz == 0)
 256                                                                 say("Not enough memory to try swapped hunk!  Assuming unswapped.\n");
 257                                                         continue;
 258                                                 }
 259                                                 reverse = !reverse;
 260                                                 /* try again */
 261                                                 where = locate_hunk(fuzz);
 262                                                 if (where == 0) {
 263                                                         /* didn't find it swapped */
 264                                                         if (!pch_swap())
 265                                                                 /* put it back to normal */
 266                                                                 fatal("lost hunk on alloc error!\n");
 267                                                         reverse = !reverse;
 268                                                 } else if (noreverse) {
 269                                                         if (!pch_swap())
 270                                                                 /* put it back to normal */
 271                                                                 fatal("lost hunk on alloc error!\n");
 272                                                         reverse = !reverse;
 273                                                         say("Ignoring previously applied (or reversed) patch.\n");
 274                                                         skip_rest_of_patch = true;
 275                                                 } else if (batch) {
 276                                                         if (verbose)
 277                                                                 say("%seversed (or previously applied) patch detected!  %s -R.",
 278                                                                     reverse ? "R" : "Unr",
 279                                                                     reverse ? "Assuming" : "Ignoring");
 280                                                 } else {
 281                                                         ask("%seversed (or previously applied) patch detected!  %s -R? [y] ",
 282                                                             reverse ? "R" : "Unr",
 283                                                             reverse ? "Assume" : "Ignore");
 284                                                         if (*buf == 'n') {
 285                                                                 ask("Apply anyway? [n] ");
 286                                                                 if (*buf != 'y')
 287                                                                         skip_rest_of_patch = true;
 288                                                                 where = 0;
 289                                                                 reverse = !reverse;
 290                                                                 if (!pch_swap())
 291                                                                         /* put it back to normal */
 292                                                                         fatal("lost hunk on alloc error!\n");
 293                                                         }
 294                                                 }
 295                                         }
 296                                 } while (!skip_rest_of_patch && where == 0 &&
 297                                     ++fuzz <= mymaxfuzz);
 298
 299                                 if (skip_rest_of_patch) {       /* just got decided */
 300                                         fclose(ofp);
 301                                         ofp = NULL;
 302                                 }
 303                         }
 304                         newwhere = pch_newfirst() + last_offset;
 305                         if (skip_rest_of_patch) {
 306                                 abort_hunk();
 307                                 failed++;
 308                                 if (verbose)
 309                                         say("Hunk #%d ignored at %ld.\n",
 310                                             hunk, newwhere);
 311                         } else if (where == 0) {
 312                                 abort_hunk();
 313                                 failed++;
 314                                 if (verbose)
 315                                         say("Hunk #%d failed at %ld.\n",
 316                                             hunk, newwhere);
 317                         } else {
 318                                 apply_hunk(where);
 319                                 if (verbose) {
 320                                         say("Hunk #%d succeeded at %ld",
 321                                             hunk, newwhere);
 322                                         if (fuzz != 0)
 323                                                 say(" with fuzz %ld", fuzz);
 324                                         if (last_offset)
 325                                                 say(" (offset %ld line%s)",
 326                                                     last_offset,
 327                                                     last_offset == 1L ? "" : "s");
 328                                         say(".\n");
 329                                 }
 330                         }
 331                 }
 332
 333                 if (out_of_mem && using_plan_a) {
 334                         Argc = Argc_last;
 335                         Argv = Argv_last;
 336                         say("\n\nRan out of memory using Plan A--trying again...\n\n");
 337                         if (ofp)
 338                                 fclose(ofp);
 339                         ofp = NULL;
 340                         if (rejfp)
 341                                 fclose(rejfp);
 342                         rejfp = NULL;
 343                         continue;
 344                 }
 345                 if (hunk == 0)
 346                         fatal("Internal error: hunk should not be 0\n");
 347
 348                 /* finish spewing out the new file */
 349                 if (!skip_rest_of_patch)
 350                         spew_output();
 351
 352                 /* and put the output where desired */
 353                 ignore_signals();
 354                 if (!skip_rest_of_patch) {
 355                         struct stat     statbuf;
 356                         char    *realout = outname;
 357
 358                         if (!check_only) {
 359                                 if (move_file(TMPOUTNAME, outname) < 0) {
 360                                         toutkeep = true;
 361                                         realout = TMPOUTNAME;
 362                                         chmod(TMPOUTNAME, filemode);
 363                                 } else
 364                                         chmod(outname, filemode);
 365
 366                                 if (remove_empty_files &&
 367                                     stat(realout, &statbuf) == 0 &&
 368                                     statbuf.st_size == 0) {
 369                                         if (verbose)
 370                                                 say("Removing %s (empty after patching).\n",
 371                                                     realout);
 372                                         unlink(realout);
 373                                 }
 374                         }
 375                 }
 376                 fclose(rejfp);
 377                 rejfp = NULL;
 378                 if (failed) {
 379                         error = 1;
 380                         if (*rejname == '\0') {
 381                                 if (strlcpy(rejname, outname,
 382                                     sizeof(rejname)) >= sizeof(rejname))
 383                                         fatal("filename %s is too long\n", outname);
 384                                 if (strlcat(rejname, REJEXT,
 385                                     sizeof(rejname)) >= sizeof(rejname))
 386                                         fatal("filename %s is too long\n", outname);
 387                         }
 388                         if (skip_rest_of_patch) {
 389                                 say("%d out of %d hunks ignored--saving rejects to %s\n",
 390                                     failed, hunk, rejname);
 391                         } else {
 392                                 say("%d out of %d hunks failed--saving rejects to %s\n",
 393                                     failed, hunk, rejname);
 394                         }
 395                         if (!check_only && move_file(TMPREJNAME, rejname) < 0)
 396                                 trejkeep = true;
 397                 }
 398                 set_signals(1);
 399         }
 400         my_exit(error);
 401         /* NOTREACHED */
 402 }
 403
 404 /* Prepare to find the next patch to do in the patch file. */
 405
 406 static void
 407 reinitialize_almost_everything(void)
 408 {
 409         re_patch();
 410         re_input();
 411
 412         input_lines = 0;
 413         last_frozen_line = 0;
 414
 415         filec = 0;
 416         if (!out_of_mem) {
 417                 free(filearg[0]);
 418                 filearg[0] = NULL;
 419         }
 420
 421         free(outname);
 422         outname = NULL;
 423
 424         last_offset = 0;
 425         diff_type = 0;
 426
 427         free(revision);
 428         revision = NULL;
 429
 430         reverse = reverse_flag_specified;
 431         skip_rest_of_patch = false;
 432
 433         get_some_switches();
 434 }
 435
 436 /* Process switches and filenames. */
 437
 438 static void
 439 get_some_switches(void)
 440 {
 441         const char *options = "b::B:cCd:D:eEfF:i:lnNo:p:r:RstuvV:x:z:";
 442         static struct option longopts[] = {
 443                 {"backup",              no_argument,            0,      'b'},
 444                 {"batch",               no_argument,            0,      't'},
 445                 {"check",               no_argument,            0,      'C'},
 446                 {"context",             no_argument,            0,      'c'},
 447                 {"debug",               required_argument,      0,      'x'},
 448                 {"directory",           required_argument,      0,      'd'},
 449                 {"ed",                  no_argument,            0,      'e'},
 450                 {"force",               no_argument,            0,      'f'},
 451                 {"forward",             no_argument,            0,      'N'},
 452                 {"fuzz",                required_argument,      0,      'F'},
 453                 {"ifdef",               required_argument,      0,      'D'},
 454                 {"input",               required_argument,      0,      'i'},
 455                 {"ignore-whitespace",   no_argument,            0,      'l'},
 456                 {"normal",              no_argument,            0,      'n'},
 457                 {"output",              required_argument,      0,      'o'},
 458                 {"prefix",              required_argument,      0,      'B'},
 459                 {"quiet",               no_argument,            0,      's'},
 460                 {"reject-file",         required_argument,      0,      'r'},
 461                 {"remove-empty-files",  no_argument,            0,      'E'},
 462                 {"reverse",             no_argument,            0,      'R'},
 463                 {"silent",              no_argument,            0,      's'},
 464                 {"strip",               required_argument,      0,      'p'},
 465                 {"suffix",              required_argument,      0,      'z'},
 466                 {"unified",             no_argument,            0,      'u'},
 467                 {"version",             no_argument,            0,      'v'},
 468                 {"version-control",     required_argument,      0,      'V'},
 469                 {"posix",               no_argument,            &posix, 1},
 470                 {NULL,                  0,                      0,      0}
 471         };
 472         int ch;
 473
 474         rejname[0] = '\0';
 475         Argc_last = Argc;
 476         Argv_last = Argv;
 477         if (!Argc)
 478                 return;
 479         optreset = optind = 1;
 480         while ((ch = getopt_long(Argc, Argv, options, longopts, NULL)) != -1) {
 481                 switch (ch) {
 482                 case 'b':
 483                         if (backup_type == none)
 484                                 backup_type = numbered_existing;
 485                         if (optarg == NULL)
 486                                 break;
 487                         if (verbose)
 488                                 say("Warning, the ``-b suffix'' option has been"
 489                                     " obsoleted by the -z option.\n");
 490                         /* FALLTHROUGH */
 491                 case 'z':
 492                         /* must directly follow 'b' case for backwards compat */
 493                         simple_backup_suffix = savestr(optarg);
 494                         break;
 495                 case 'B':
 496                         origprae = savestr(optarg);
 497                         break;
 498                 case 'c':
 499                         diff_type = CONTEXT_DIFF;
 500                         break;
 501                 case 'C':
 502                         check_only = true;
 503                         break;
 504                 case 'd':
 505                         if (chdir(optarg) < 0)
 506                                 pfatal("can't cd to %s", optarg);
 507                         break;
 508                 case 'D':
 509                         do_defines = true;
 510                         if (!isalpha((unsigned char)*optarg) && *optarg != '_')
 511                                 fatal("argument to -D is not an identifier\n");
 512                         snprintf(if_defined, sizeof if_defined,
 513                             "#ifdef %s\n", optarg);
 514                         snprintf(not_defined, sizeof not_defined,
 515                             "#ifndef %s\n", optarg);
 516                         snprintf(end_defined, sizeof end_defined,
 517                             "#endif /* %s */\n", optarg);
 518                         break;
 519                 case 'e':
 520                         diff_type = ED_DIFF;
 521                         break;
 522                 case 'E':
 523                         remove_empty_files = true;
 524                         break;
 525                 case 'f':
 526                         force = true;
 527                         break;
 528                 case 'F':
 529                         maxfuzz = atoi(optarg);
 530                         break;
 531                 case 'i':
 532                         if (++filec == MAXFILEC)
 533                                 fatal("too many file arguments\n");
 534                         filearg[filec] = savestr(optarg);
 535                         break;
 536                 case 'l':
 537                         canonicalize = true;
 538                         break;
 539                 case 'n':
 540                         diff_type = NORMAL_DIFF;
 541                         break;
 542                 case 'N':
 543                         noreverse = true;
 544                         break;
 545                 case 'o':
 546                         outname = savestr(optarg);
 547                         break;
 548                 case 'p':
 549                         strippath = atoi(optarg);
 550                         break;
 551                 case 'r':
 552                         if (strlcpy(rejname, optarg,
 553                             sizeof(rejname)) >= sizeof(rejname))
 554                                 fatal("argument for -r is too long\n");
 555                         break;
 556                 case 'R':
 557                         reverse = true;
 558                         reverse_flag_specified = true;
 559                         break;
 560                 case 's':
 561                         verbose = false;
 562                         break;
 563                 case 't':
 564                         batch = true;
 565                         break;
 566                 case 'u':
 567                         diff_type = UNI_DIFF;
 568                         break;
 569                 case 'v':
 570                         version();
 571                         break;
 572                 case 'V':
 573                         backup_type = get_version(optarg);
 574                         break;
 575 #ifdef DEBUGGING
 576                 case 'x':
 577                         debug = atoi(optarg);
 578                         break;
 579 #endif
 580                 default:
 581                         if (ch != '\0')
 582                                 usage();
 583                         break;
 584                 }
 585         }
 586         Argc -= optind;
 587         Argv += optind;
 588
 589         if (Argc > 0) {
 590                 filearg[0] = savestr(*Argv++);
 591                 Argc--;
 592                 while (Argc > 0) {
 593                         if (++filec == MAXFILEC)
 594                                 fatal("too many file arguments\n");
 595                         filearg[filec] = savestr(*Argv++);
 596                         Argc--;
 597                 }
 598         }
 599
 600         if (getenv("POSIXLY_CORRECT") != NULL)
 601                 posix = 1;
 602 }
 603
 604 static void
 605 usage(void)
 606 {
 607         fprintf(stderr,
 608 "usage: patch [-bCcEeflNnRstuv] [-B backup-prefix] [-D symbol] [-d directory]\n"
 609 "             [-F max-fuzz] [-i patchfile] [-o out-file] [-p strip-count]\n"
 610 "             [-r rej-name] [-V t | nil | never] [-x number] [-z backup-ext]\n"
 611 "             [--posix] [origfile [patchfile]]\n"
 612 "       patch <patchfile\n");
 613         my_exit(EXIT_SUCCESS);
 614 }
 615
 616 /*
 617  * Attempt to find the right place to apply this hunk of patch.
 618  */
 619 static LINENUM
 620 locate_hunk(LINENUM fuzz)
 621 {
 622         LINENUM first_guess = pch_first() + last_offset;
 623         LINENUM offset;
 624         LINENUM pat_lines = pch_ptrn_lines();
 625         LINENUM max_pos_offset = input_lines - first_guess - pat_lines + 1;
 626         LINENUM max_neg_offset = first_guess - last_frozen_line - 1 + pch_context();
 627
 628         if (pat_lines == 0) {           /* null range matches always */
 629                 if (verbose && fuzz == 0 && (diff_type == CONTEXT_DIFF
 630                     || diff_type == NEW_CONTEXT_DIFF
 631                     || diff_type == UNI_DIFF)) {
 632                         say("Empty context always matches.\n");
 633                 }
 634                 return (first_guess);
 635         }
 636         if (max_neg_offset >= first_guess)      /* do not try lines < 0 */
 637                 max_neg_offset = first_guess - 1;
 638         if (first_guess <= input_lines && patch_match(first_guess, 0, fuzz))
 639                 return first_guess;
 640         for (offset = 1; ; offset++) {
 641                 bool    check_after = (offset <= max_pos_offset);
 642                 bool    check_before = (offset <= max_neg_offset);
 643
 644                 if (check_after && patch_match(first_guess, offset, fuzz)) {
 645 #ifdef DEBUGGING
 646                         if (debug & 1)
 647                                 say("Offset changing from %ld to %ld\n",
 648                                     last_offset, offset);
 649 #endif
 650                         last_offset = offset;
 651                         return first_guess + offset;
 652                 } else if (check_before && patch_match(first_guess, -offset, fuzz)) {
 653 #ifdef DEBUGGING
 654                         if (debug & 1)
 655                                 say("Offset changing from %ld to %ld\n",
 656                                     last_offset, -offset);
 657 #endif
 658                         last_offset = -offset;
 659                         return first_guess - offset;
 660                 } else if (!check_before && !check_after)
 661                         return 0;
 662         }
 663 }
 664
 665 /* We did not find the pattern, dump out the hunk so they can handle it. */
 666
 667 static void
 668 abort_context_hunk(void)
 669 {
 670         LINENUM i;
 671         const LINENUM   pat_end = pch_end();
 672         /*
 673          * add in last_offset to guess the same as the previous successful
 674          * hunk
 675          */
 676         const LINENUM   oldfirst = pch_first() + last_offset;
 677         const LINENUM   newfirst = pch_newfirst() + last_offset;
 678         const LINENUM   oldlast = oldfirst + pch_ptrn_lines() - 1;
 679         const LINENUM   newlast = newfirst + pch_repl_lines() - 1;
 680         const char      *stars = (diff_type >= NEW_CONTEXT_DIFF ? " ****" : "");
 681         const char      *minuses = (diff_type >= NEW_CONTEXT_DIFF ? " ----" : " -----");
 682
 683         fprintf(rejfp, "***************\n");
 684         for (i = 0; i <= pat_end; i++) {
 685                 switch (pch_char(i)) {
 686                 case '*':
 687                         if (oldlast < oldfirst)
 688                                 fprintf(rejfp, "*** 0%s\n", stars);
 689                         else if (oldlast == oldfirst)
 690                                 fprintf(rejfp, "*** %ld%s\n", oldfirst, stars);
 691                         else
 692                                 fprintf(rejfp, "*** %ld,%ld%s\n", oldfirst,
 693                                     oldlast, stars);
 694                         break;
 695                 case '=':
 696                         if (newlast < newfirst)
 697                                 fprintf(rejfp, "--- 0%s\n", minuses);
 698                         else if (newlast == newfirst)
 699                                 fprintf(rejfp, "--- %ld%s\n", newfirst, minuses);
 700                         else
 701                                 fprintf(rejfp, "--- %ld,%ld%s\n", newfirst,
 702                                     newlast, minuses);
 703                         break;
 704                 case '\n':
 705                         fprintf(rejfp, "%s", pfetch(i));
 706                         break;
 707                 case ' ':
 708                 case '-':
 709                 case '+':
 710                 case '!':
 711                         fprintf(rejfp, "%c %s", pch_char(i), pfetch(i));
 712                         break;
 713                 default:
 714                         fatal("fatal internal error in abort_context_hunk\n");
 715                 }
 716         }
 717 }
 718
 719 static void
 720 rej_line(int ch, LINENUM i)
 721 {
 722         size_t len;
 723         const char *line = pfetch(i);
 724
 725         len = strlen(line);
 726
 727         fprintf(rejfp, "%c%s", ch, line);
 728         if (len == 0 || line[len-1] != '\n')
 729                 fprintf(rejfp, "\n\\ No newline at end of file\n");
 730 }
 731
 732 static void
 733 abort_hunk(void)
 734 {
 735         LINENUM         i, j, split;
 736         int             ch1, ch2;
 737         const LINENUM   pat_end = pch_end();
 738         const LINENUM   oldfirst = pch_first() + last_offset;
 739         const LINENUM   newfirst = pch_newfirst() + last_offset;
 740
 741         if (diff_type != UNI_DIFF) {
 742                 abort_context_hunk();
 743                 return;
 744         }
 745         split = -1;
 746         for (i = 0; i <= pat_end; i++) {
 747                 if (pch_char(i) == '=') {
 748                         split = i;
 749                         break;
 750                 }
 751         }
 752         if (split == -1) {
 753                 fprintf(rejfp, "malformed hunk: no split found\n");
 754                 return;
 755         }
 756         i = 0;
 757         j = split + 1;
 758         fprintf(rejfp, "@@ -%ld,%ld +%ld,%ld @@\n",
 759             pch_ptrn_lines() ? oldfirst : 0,
 760             pch_ptrn_lines(), newfirst, pch_repl_lines());
 761         while (i < split || j <= pat_end) {
 762                 ch1 = i < split ? pch_char(i) : -1;
 763                 ch2 = j <= pat_end ? pch_char(j) : -1;
 764                 if (ch1 == '-') {
 765                         rej_line('-', i);
 766                         i++;
 767                 } else if (ch1 == ' ' && ch2 == ' ') {
 768                         rej_line(' ', i);
 769                         i++;
 770                         j++;
 771                 } else if (ch1 == '!' && ch2 == '!') {
 772                         while (i < split && ch1 == '!') {
 773                                 rej_line('-', i);
 774                                 i++;
 775                                 ch1 = i < split ? pch_char(i) : -1;
 776                         }
 777                         while (j <= pat_end && ch2 == '!') {
 778                                 rej_line('+', j);
 779                                 j++;
 780                                 ch2 = j <= pat_end ? pch_char(j) : -1;
 781                         }
 782                 } else if (ch1 == '*') {
 783                         i++;
 784                 } else if (ch2 == '+' || ch2 == ' ') {
 785                         rej_line(ch2, j);
 786                         j++;
 787                 } else {
 788                         fprintf(rejfp, "internal error on (%ld %ld %ld)\n",
 789                             i, split, j);
 790                         rej_line(ch1, i);
 791                         rej_line(ch2, j);
 792                         return;
 793                 }
 794         }
 795 }
 796
 797 /* We found where to apply it (we hope), so do it. */
 798
 799 static void
 800 apply_hunk(LINENUM where)
 801 {
 802         LINENUM         old = 1;
 803         const LINENUM   lastline = pch_ptrn_lines();
 804         LINENUM         new = lastline + 1;
 805 #define OUTSIDE 0
 806 #define IN_IFNDEF 1
 807 #define IN_IFDEF 2
 808 #define IN_ELSE 3
 809         int             def_state = OUTSIDE;
 810         const LINENUM   pat_end = pch_end();
 811
 812         where--;
 813         while (pch_char(new) == '=' || pch_char(new) == '\n')
 814                 new++;
 815
 816         while (old <= lastline) {
 817                 if (pch_char(old) == '-') {
 818                         copy_till(where + old - 1, false);
 819                         if (do_defines) {
 820                                 if (def_state == OUTSIDE) {
 821                                         fputs(not_defined, ofp);
 822                                         def_state = IN_IFNDEF;
 823                                 } else if (def_state == IN_IFDEF) {
 824                                         fputs(else_defined, ofp);
 825                                         def_state = IN_ELSE;
 826                                 }
 827                                 fputs(pfetch(old), ofp);
 828                         }
 829                         last_frozen_line++;
 830                         old++;
 831                 } else if (new > pat_end) {
 832                         break;
 833                 } else if (pch_char(new) == '+') {
 834                         copy_till(where + old - 1, false);
 835                         if (do_defines) {
 836                                 if (def_state == IN_IFNDEF) {
 837                                         fputs(else_defined, ofp);
 838                                         def_state = IN_ELSE;
 839                                 } else if (def_state == OUTSIDE) {
 840                                         fputs(if_defined, ofp);
 841                                         def_state = IN_IFDEF;
 842                                 }
 843                         }
 844                         fputs(pfetch(new), ofp);
 845                         new++;
 846                 } else if (pch_char(new) != pch_char(old)) {
 847                         say("Out-of-sync patch, lines %ld,%ld--mangled text or line numbers, maybe?\n",
 848                             pch_hunk_beg() + old,
 849                             pch_hunk_beg() + new);
 850 #ifdef DEBUGGING
 851                         say("oldchar = '%c', newchar = '%c'\n",
 852                             pch_char(old), pch_char(new));
 853 #endif
 854                         my_exit(2);
 855                 } else if (pch_char(new) == '!') {
 856                         copy_till(where + old - 1, false);
 857                         if (do_defines) {
 858                                 fputs(not_defined, ofp);
 859                                 def_state = IN_IFNDEF;
 860                         }
 861                         while (pch_char(old) == '!') {
 862                                 if (do_defines) {
 863                                         fputs(pfetch(old), ofp);
 864                                 }
 865                                 last_frozen_line++;
 866                                 old++;
 867                         }
 868                         if (do_defines) {
 869                                 fputs(else_defined, ofp);
 870                                 def_state = IN_ELSE;
 871                         }
 872                         while (pch_char(new) == '!') {
 873                                 fputs(pfetch(new), ofp);
 874                                 new++;
 875                         }
 876                 } else {
 877                         if (pch_char(new) != ' ')
 878                                 fatal("Internal error: expected ' '\n");
 879                         old++;
 880                         new++;
 881                         if (do_defines && def_state != OUTSIDE) {
 882                                 fputs(end_defined, ofp);
 883                                 def_state = OUTSIDE;
 884                         }
 885                 }
 886         }
 887         if (new <= pat_end && pch_char(new) == '+') {
 888                 copy_till(where + old - 1, false);
 889                 if (do_defines) {
 890                         if (def_state == OUTSIDE) {
 891                                 fputs(if_defined, ofp);
 892                                 def_state = IN_IFDEF;
 893                         } else if (def_state == IN_IFNDEF) {
 894                                 fputs(else_defined, ofp);
 895                                 def_state = IN_ELSE;
 896                         }
 897                 }
 898                 while (new <= pat_end && pch_char(new) == '+') {
 899                         fputs(pfetch(new), ofp);
 900                         new++;
 901                 }
 902         }
 903         if (do_defines && def_state != OUTSIDE) {
 904                 fputs(end_defined, ofp);
 905         }
 906 }
 907
 908 /*
 909  * Open the new file.
 910  */
 911 static void
 912 init_output(const char *name)
 913 {
 914         ofp = fopen(name, "w");
 915         if (ofp == NULL)
 916                 pfatal("can't create %s", name);
 917 }
 918
 919 /*
 920  * Open a file to put hunks we can't locate.
 921  */
 922 static void
 923 init_reject(const char *name)
 924 {
 925         rejfp = fopen(name, "w");
 926         if (rejfp == NULL)
 927                 pfatal("can't create %s", name);
 928 }
 929
 930 /*
 931  * Copy input file to output, up to wherever hunk is to be applied.
 932  * If endoffile is true, treat the last line specially since it may
 933  * lack a newline.
 934  */
 935 static void
 936 copy_till(LINENUM lastline, bool endoffile)
 937 {
 938         if (last_frozen_line > lastline)
 939                 fatal("misordered hunks! output would be garbled\n");
 940         while (last_frozen_line < lastline) {
 941                 if (++last_frozen_line == lastline && endoffile)
 942                         dump_line(last_frozen_line, !last_line_missing_eol);
 943                 else
 944                         dump_line(last_frozen_line, true);
 945         }
 946 }
 947
 948 /*
 949  * Finish copying the input file to the output file.
 950  */
 951 static void
 952 spew_output(void)
 953 {
 954 #ifdef DEBUGGING
 955         if (debug & 256)
 956                 say("il=%ld lfl=%ld\n", input_lines, last_frozen_line);
 957 #endif
 958         if (input_lines)
 959                 copy_till(input_lines, true);   /* dump remainder of file */
 960         fclose(ofp);
 961         ofp = NULL;
 962 }
 963
 964 /*
 965  * Copy one line from input to output.
 966  */
 967 static void
 968 dump_line(LINENUM line, bool write_newline)
 969 {
 970         char    *s;
 971
 972         s = ifetch(line, 0);
 973         if (s == NULL)
 974                 return;
 975         /* Note: string is not NUL terminated. */
 976         for (; *s != '\n'; s++)
 977                 putc(*s, ofp);
 978         if (write_newline)
 979                 putc('\n', ofp);
 980 }
 981
 982 /*
 983  * Does the patch pattern match at line base+offset?
 984  */
 985 static bool
 986 patch_match(LINENUM base, LINENUM offset, LINENUM fuzz)
 987 {
 988         LINENUM         pline = 1 + fuzz;
 989         LINENUM         iline;
 990         LINENUM         pat_lines = pch_ptrn_lines() - fuzz;
 991         const char      *ilineptr;
 992         const char      *plineptr;
 993         short           plinelen;
 994
 995         for (iline = base + offset + fuzz; pline <= pat_lines; pline++, iline++) {
 996                 ilineptr = ifetch(iline, offset >= 0);
 997                 if (ilineptr == NULL)
 998                         return false;
 999                 plineptr = pfetch(pline);
1000                 plinelen = pch_line_len(pline);
1001                 if (canonicalize) {
1002                         if (!similar(ilineptr, plineptr, plinelen))
1003                                 return false;
1004                 } else if (strnNE(ilineptr, plineptr, plinelen))
1005                         return false;
1006                 if (iline == input_lines) {
1007                         /*
1008                          * We are looking at the last line of the file.
1009                          * If the file has no eol, the patch line should
1010                          * not have one either and vice-versa. Note that
1011                          * plinelen > 0.
1012                          */
1013                         if (last_line_missing_eol) {
1014                                 if (plineptr[plinelen - 1] == '\n')
1015                                         return false;
1016                         } else {
1017                                 if (plineptr[plinelen - 1] != '\n')
1018                                         return false;
1019                         }
1020                 }
1021         }
1022         return true;
1023 }
1024
1025 /*
1026  * Do two lines match with canonicalized white space?
1027  */
1028 static bool
1029 similar(const char *a, const char *b, int len)
1030 {
1031         while (len) {
1032                 if (isspace((unsigned char)*b)) {       /* whitespace (or \n) to match? */
1033                         if (!isspace((unsigned char)*a))        /* no corresponding whitespace? */
1034                                 return false;
1035                         while (len && isspace((unsigned char)*b) && *b != '\n')
1036                                 b++, len--;     /* skip pattern whitespace */
1037                         while (isspace((unsigned char)*a) && *a != '\n')
1038                                 a++;    /* skip target whitespace */
1039                         if (*a == '\n' || *b == '\n')
1040                                 return (*a == *b);      /* should end in sync */
1041                 } else if (*a++ != *b++)        /* match non-whitespace chars */
1042                         return false;
1043                 else
1044                         len--;  /* probably not necessary */
1045         }
1046         return true;            /* actually, this is not reached */
1047         /* since there is always a \n */
1048 }