usr.bin/patch/patch.c

   1 /*-
   2  * Copyright 1986, Larry Wall
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following condition is met:
   6  * 1. Redistributions of source code must retain the above copyright notice,
   7  * this condition and the following disclaimer.
   8  *
   9  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
  10  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  11  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  12  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  13  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  14  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  15  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  16  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  17  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  18  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  19  * SUCH DAMAGE.
  20  *
  21  * patch - a program to apply diffs to original files
  22  *
  23  * -C option added in 1998, original code by Marc Espie, based on FreeBSD
  24  * behaviour
  25  *
  26  * $OpenBSD: patch.c,v 1.54 2014/12/13 10:31:07 tobias Exp $
  27  *
  28  */
  29
  30 #include <sys/types.h>
  31 #include <sys/stat.h>
  32
  33 #include <assert.h>
  34 #include <ctype.h>
  35 #include <getopt.h>
  36 #include <limits.h>
  37 #include <stdio.h>
  38 #include <string.h>
  39 #include <stdlib.h>
  40 #include <unistd.h>
  41
  42 #include "common.h"
  43 #include "util.h"
  44 #include "pch.h"
  45 #include "inp.h"
  46 #include "backupfile.h"
  47 #include "pathnames.h"
  48
  49 mode_t          filemode = 0644;
  50
  51 char            *buf;                   /* general purpose buffer */
  52 size_t          buf_size;               /* size of the 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 bool            nonempty_patchf_seen = false;   /* seen nonempty patch file? */
  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 bool     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 static bool     handle_creation(bool, bool *);
 107
 108 /* true if -E was specified on command line.  */
 109 static bool     remove_empty_files = false;
 110
 111 /* true if -R was specified on command line.  */
 112 static bool     reverse_flag_specified = false;
 113
 114 static bool     Vflag = false;
 115
 116 /* buffer holding the name of the rejected patch file. */
 117 static char     rejname[PATH_MAX];
 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         struct stat statbuf;
 152         int     error = 0, hunk, failed, i, fd;
 153         bool    out_creating, out_existed, patch_seen, remove_file;
 154         bool    reverse_seen;
 155         LINENUM where = 0, newwhere, fuzz, mymaxfuzz;
 156         const   char *tmpdir;
 157         char    *v;
 158
 159         setvbuf(stdout, NULL, _IOLBF, 0);
 160         setvbuf(stderr, NULL, _IOLBF, 0);
 161         for (i = 0; i < MAXFILEC; i++)
 162                 filearg[i] = NULL;
 163
 164         buf_size = INITLINELEN;
 165         buf = malloc((unsigned)(buf_size));
 166         if (buf == NULL)
 167                 fatal("out of memory\n");
 168
 169         /* Cons up the names of the temporary files.  */
 170         if ((tmpdir = getenv("TMPDIR")) == NULL || *tmpdir == '\0')
 171                 tmpdir = _PATH_TMP;
 172         for (i = strlen(tmpdir) - 1; i > 0 && tmpdir[i] == '/'; i--)
 173                 ;
 174         i++;
 175         if (asprintf(&TMPOUTNAME, "%.*s/patchoXXXXXXXXXX", i, tmpdir) == -1)
 176                 fatal("cannot allocate memory");
 177         if ((fd = mkstemp(TMPOUTNAME)) < 0)
 178                 pfatal("can't create %s", TMPOUTNAME);
 179         close(fd);
 180
 181         if (asprintf(&TMPINNAME, "%.*s/patchiXXXXXXXXXX", i, tmpdir) == -1)
 182                 fatal("cannot allocate memory");
 183         if ((fd = mkstemp(TMPINNAME)) < 0)
 184                 pfatal("can't create %s", TMPINNAME);
 185         close(fd);
 186
 187         if (asprintf(&TMPREJNAME, "%.*s/patchrXXXXXXXXXX", i, tmpdir) == -1)
 188                 fatal("cannot allocate memory");
 189         if ((fd = mkstemp(TMPREJNAME)) < 0)
 190                 pfatal("can't create %s", TMPREJNAME);
 191         close(fd);
 192
 193         if (asprintf(&TMPPATNAME, "%.*s/patchpXXXXXXXXXX", i, tmpdir) == -1)
 194                 fatal("cannot allocate memory");
 195         if ((fd = mkstemp(TMPPATNAME)) < 0)
 196                 pfatal("can't create %s", TMPPATNAME);
 197         close(fd);
 198
 199         v = getenv("SIMPLE_BACKUP_SUFFIX");
 200         if (v)
 201                 simple_backup_suffix = v;
 202         else
 203                 simple_backup_suffix = ORIGEXT;
 204
 205         /* parse switches */
 206         Argc = argc;
 207         Argv = argv;
 208         get_some_switches();
 209
 210         if (!Vflag) {
 211                 if ((v = getenv("PATCH_VERSION_CONTROL")) == NULL)
 212                         v = getenv("VERSION_CONTROL");
 213                 if (v != NULL || !posix)
 214                         backup_type = get_version(v);   /* OK to pass NULL. */
 215         }
 216
 217         /* make sure we clean up /tmp in case of disaster */
 218         set_signals(0);
 219
 220         patch_seen = false;
 221         for (open_patch_file(filearg[1]); there_is_another_patch();
 222             reinitialize_almost_everything()) {
 223                 /* for each patch in patch file */
 224
 225                 if (source_file != NULL && (diff_type == CONTEXT_DIFF ||
 226                     diff_type == NEW_CONTEXT_DIFF ||
 227                     diff_type == UNI_DIFF))
 228                         out_creating = strcmp(source_file, _PATH_DEVNULL) == 0;
 229                 else
 230                         out_creating = false;
 231                 patch_seen = true;
 232
 233                 warn_on_invalid_line = true;
 234
 235                 if (outname == NULL)
 236                         outname = xstrdup(filearg[0]);
 237
 238                 /*
 239                  * At this point, we know if we're supposed to be creating the
 240                  * file and we know if we should be trying to handle a conflict
 241                  * between the patch and the file already existing.  We defer
 242                  * handling it until hunk processing because we want to swap
 243                  * the hunk if they opt to reverse it, but we want to make sure
 244                  * we *can* swap the hunk without running into memory issues
 245                  * before we offer it.  We also want to be verbose if flags or
 246                  * user decision cause us to skip -- this is explained a little
 247                  * more later.
 248                  */
 249                 out_existed = stat(outname, &statbuf) == 0;
 250
 251                 /* for ed script just up and do it and exit */
 252                 if (diff_type == ED_DIFF) {
 253                         do_ed_script();
 254                         continue;
 255                 }
 256                 /* initialize the patched file */
 257                 if (!skip_rest_of_patch)
 258                         init_output(TMPOUTNAME);
 259
 260                 /* initialize reject file */
 261                 init_reject(TMPREJNAME);
 262
 263                 /* find out where all the lines are */
 264                 if (!skip_rest_of_patch)
 265                         scan_input(filearg[0]);
 266
 267                 /*
 268                  * from here on, open no standard i/o files, because
 269                  * malloc might misfire and we can't catch it easily
 270                  */
 271
 272                 /* apply each hunk of patch */
 273                 hunk = 0;
 274                 failed = 0;
 275                 reverse_seen = false;
 276                 out_of_mem = false;
 277                 remove_file = false;
 278                 while (another_hunk()) {
 279                         assert(!out_creating || hunk == 0);
 280                         hunk++;
 281                         fuzz = 0;
 282
 283                         /*
 284                          * There are only three cases in handle_creation() that
 285                          * results in us skipping hunk location, in order:
 286                          *
 287                          * 1.) Potentially reversed but -f/--force'd,
 288                          * 2.) Potentially reversed but -N/--forward'd
 289                          * 3.) Reversed and the user's opted to not apply it.
 290                          *
 291                          * In all three cases, we still want to inform the user
 292                          * that we're ignoring it in the standard way, which is
 293                          * also tied to this hunk processing loop.
 294                          */
 295                         if (out_creating)
 296                                 reverse_seen = handle_creation(out_existed,
 297                                     &remove_file);
 298
 299                         mymaxfuzz = pch_context();
 300                         if (maxfuzz < mymaxfuzz)
 301                                 mymaxfuzz = maxfuzz;
 302                         if (!skip_rest_of_patch) {
 303                                 do {
 304                                         where = locate_hunk(fuzz);
 305                                         if (hunk == 1 && where == 0 && !force && !reverse_seen) {
 306                                                 /* dwim for reversed patch? */
 307                                                 if (!pch_swap()) {
 308                                                         if (fuzz == 0)
 309                                                                 say("Not enough memory to try swapped hunk!  Assuming unswapped.\n");
 310                                                         continue;
 311                                                 }
 312                                                 reverse = !reverse;
 313                                                 /* try again */
 314                                                 where = locate_hunk(fuzz);
 315                                                 if (where == 0) {
 316                                                         /* didn't find it swapped */
 317                                                         if (!pch_swap())
 318                                                                 /* put it back to normal */
 319                                                                 fatal("lost hunk on alloc error!\n");
 320                                                         reverse = !reverse;
 321                                                 } else if (noreverse) {
 322                                                         if (!pch_swap())
 323                                                                 /* put it back to normal */
 324                                                                 fatal("lost hunk on alloc error!\n");
 325                                                         reverse = !reverse;
 326                                                         say("Ignoring previously applied (or reversed) patch.\n");
 327                                                         skip_rest_of_patch = true;
 328                                                 } else if (batch) {
 329                                                         if (verbose)
 330                                                                 say("%seversed (or previously applied) patch detected!  %s -R.",
 331                                                                     reverse ? "R" : "Unr",
 332                                                                     reverse ? "Assuming" : "Ignoring");
 333                                                 } else {
 334                                                         ask("%seversed (or previously applied) patch detected!  %s -R? [y] ",
 335                                                             reverse ? "R" : "Unr",
 336                                                             reverse ? "Assume" : "Ignore");
 337                                                         if (*buf == 'n') {
 338                                                                 ask("Apply anyway? [n] ");
 339                                                                 if (*buf != 'y')
 340                                                                         skip_rest_of_patch = true;
 341                                                                 else
 342                                                                         reverse_seen = true;
 343                                                                 where = 0;
 344                                                                 reverse = !reverse;
 345                                                                 if (!pch_swap())
 346                                                                         /* put it back to normal */
 347                                                                         fatal("lost hunk on alloc error!\n");
 348                                                         }
 349                                                 }
 350                                         }
 351                                 } while (!skip_rest_of_patch && where == 0 &&
 352                                     ++fuzz <= mymaxfuzz);
 353
 354                                 if (skip_rest_of_patch) {       /* just got decided */
 355                                         if (ferror(ofp) || fclose(ofp)) {
 356                                                 say("Error writing %s\n",
 357                                                     TMPOUTNAME);
 358                                                 error = 1;
 359                                         }
 360                                         ofp = NULL;
 361                                 }
 362                         }
 363                         newwhere = pch_newfirst() + last_offset;
 364                         if (skip_rest_of_patch) {
 365                                 abort_hunk();
 366                                 failed++;
 367                                 if (verbose)
 368                                         say("Hunk #%d ignored at %ld.\n",
 369                                             hunk, newwhere);
 370                         } else if (where == 0) {
 371                                 abort_hunk();
 372                                 failed++;
 373                                 if (verbose)
 374                                         say("Hunk #%d failed at %ld.\n",
 375                                             hunk, newwhere);
 376                         } else {
 377                                 apply_hunk(where);
 378                                 if (verbose) {
 379                                         say("Hunk #%d succeeded at %ld",
 380                                             hunk, newwhere);
 381                                         if (fuzz != 0)
 382                                                 say(" with fuzz %ld", fuzz);
 383                                         if (last_offset)
 384                                                 say(" (offset %ld line%s)",
 385                                                     last_offset,
 386                                                     last_offset == 1L ? "" : "s");
 387                                         say(".\n");
 388                                 }
 389                         }
 390                 }
 391
 392                 if (out_of_mem && using_plan_a) {
 393                         Argc = Argc_last;
 394                         Argv = Argv_last;
 395                         say("\n\nRan out of memory using Plan A--trying again...\n\n");
 396                         if (ofp)
 397                                 fclose(ofp);
 398                         ofp = NULL;
 399                         if (rejfp)
 400                                 fclose(rejfp);
 401                         rejfp = NULL;
 402                         continue;
 403                 }
 404                 if (hunk == 0)
 405                         fatal("Internal error: hunk should not be 0\n");
 406
 407                 /* finish spewing out the new file */
 408                 if (!skip_rest_of_patch && !spew_output()) {
 409                         say("Can't write %s\n", TMPOUTNAME);
 410                         error = 1;
 411                 }
 412
 413                 /* and put the output where desired */
 414                 ignore_signals();
 415                 if (!skip_rest_of_patch) {
 416                         char    *realout = outname;
 417
 418                         if (!check_only) {
 419                                 if (move_file(TMPOUTNAME, outname) < 0) {
 420                                         toutkeep = true;
 421                                         realout = TMPOUTNAME;
 422                                         chmod(TMPOUTNAME, filemode);
 423                                 } else
 424                                         chmod(outname, filemode);
 425
 426                                 /*
 427                                  * remove_file is a per-patch flag indicating
 428                                  * whether it's OK to remove the empty file.
 429                                  * This is specifically set when we're reversing
 430                                  * the creation of a file and it ends up empty.
 431                                  * This is an exception to the global policy
 432                                  * (remove_empty_files) because the user would
 433                                  * likely not expect the reverse of file
 434                                  * creation to leave an empty file laying
 435                                  * around.
 436                                  */
 437                                 if ((remove_empty_files || remove_file) &&
 438                                     stat(realout, &statbuf) == 0 &&
 439                                     statbuf.st_size == 0) {
 440                                         if (verbose)
 441                                                 say("Removing %s (empty after patching).\n",
 442                                                     realout);
 443                                         unlink(realout);
 444                                 }
 445                         }
 446                 }
 447                 if (ferror(rejfp) || fclose(rejfp)) {
 448                         say("Error writing %s\n", rejname);
 449                         error = 1;
 450                 }
 451                 rejfp = NULL;
 452                 if (failed) {
 453                         error = 1;
 454                         if (*rejname == '\0') {
 455                                 if (strlcpy(rejname, outname,
 456                                     sizeof(rejname)) >= sizeof(rejname))
 457                                         fatal("filename %s is too long\n", outname);
 458                                 if (strlcat(rejname, REJEXT,
 459                                     sizeof(rejname)) >= sizeof(rejname))
 460                                         fatal("filename %s is too long\n", outname);
 461                         }
 462                         if (!check_only)
 463                                 say("%d out of %d hunks %s--saving rejects to %s\n",
 464                                     failed, hunk, skip_rest_of_patch ? "ignored" : "failed", rejname);
 465                         else if (filearg[0] != NULL)
 466                                 say("%d out of %d hunks %s while patching %s\n",
 467                                     failed, hunk, skip_rest_of_patch ? "ignored" : "failed", filearg[0]);
 468                         else
 469                                 /* File prompt ignored, just note # hunks. */
 470                                 say("%d out of %d hunks %s\n",
 471                                     failed, hunk, skip_rest_of_patch ? "ignored" : "failed");
 472                         if (!check_only && move_file(TMPREJNAME, rejname) < 0)
 473                                 trejkeep = true;
 474                 }
 475                 set_signals(1);
 476         }
 477
 478         if (!patch_seen && nonempty_patchf_seen)
 479                 error = 2;
 480
 481         my_exit(error);
 482         /* NOTREACHED */
 483 }
 484
 485 /* Prepare to find the next patch to do in the patch file. */
 486
 487 static void
 488 reinitialize_almost_everything(void)
 489 {
 490         re_patch();
 491         re_input();
 492
 493         input_lines = 0;
 494         last_frozen_line = 0;
 495
 496         filec = 0;
 497         if (!out_of_mem) {
 498                 free(filearg[0]);
 499                 filearg[0] = NULL;
 500         }
 501
 502         free(source_file);
 503         source_file = NULL;
 504
 505         free(outname);
 506         outname = NULL;
 507
 508         last_offset = 0;
 509         diff_type = 0;
 510
 511         free(revision);
 512         revision = NULL;
 513
 514         reverse = reverse_flag_specified;
 515         skip_rest_of_patch = false;
 516
 517         get_some_switches();
 518 }
 519
 520 /* Process switches and filenames. */
 521
 522 static void
 523 get_some_switches(void)
 524 {
 525         const char *options = "b::B:cCd:D:eEfF:i:lnNo:p:r:RstuvV:x:z:";
 526         static struct option longopts[] = {
 527                 {"backup",              no_argument,            0,      'b'},
 528                 {"batch",               no_argument,            0,      't'},
 529                 {"check",               no_argument,            0,      'C'},
 530                 {"context",             no_argument,            0,      'c'},
 531                 {"debug",               required_argument,      0,      'x'},
 532                 {"directory",           required_argument,      0,      'd'},
 533                 {"dry-run",             no_argument,            0,      'C'},
 534                 {"ed",                  no_argument,            0,      'e'},
 535                 {"force",               no_argument,            0,      'f'},
 536                 {"forward",             no_argument,            0,      'N'},
 537                 {"fuzz",                required_argument,      0,      'F'},
 538                 {"ifdef",               required_argument,      0,      'D'},
 539                 {"input",               required_argument,      0,      'i'},
 540                 {"ignore-whitespace",   no_argument,            0,      'l'},
 541                 {"normal",              no_argument,            0,      'n'},
 542                 {"output",              required_argument,      0,      'o'},
 543                 {"prefix",              required_argument,      0,      'B'},
 544                 {"quiet",               no_argument,            0,      's'},
 545                 {"reject-file",         required_argument,      0,      'r'},
 546                 {"remove-empty-files",  no_argument,            0,      'E'},
 547                 {"reverse",             no_argument,            0,      'R'},
 548                 {"silent",              no_argument,            0,      's'},
 549                 {"strip",               required_argument,      0,      'p'},
 550                 {"suffix",              required_argument,      0,      'z'},
 551                 {"unified",             no_argument,            0,      'u'},
 552                 {"version",             no_argument,            0,      'v'},
 553                 {"version-control",     required_argument,      0,      'V'},
 554                 {"posix",               no_argument,            &posix, 1},
 555                 {NULL,                  0,                      0,      0}
 556         };
 557         int ch;
 558
 559         rejname[0] = '\0';
 560         Argc_last = Argc;
 561         Argv_last = Argv;
 562         if (!Argc)
 563                 return;
 564         optreset = optind = 1;
 565         while ((ch = getopt_long(Argc, Argv, options, longopts, NULL)) != -1) {
 566                 switch (ch) {
 567                 case 'b':
 568                         if (backup_type == none)
 569                                 backup_type = numbered_existing;
 570                         if (optarg == NULL)
 571                                 break;
 572                         if (verbose)
 573                                 say("Warning, the ``-b suffix'' option has been"
 574                                     " obsoleted by the -z option.\n");
 575                         /* FALLTHROUGH */
 576                 case 'z':
 577                         /* must directly follow 'b' case for backwards compat */
 578                         simple_backup_suffix = xstrdup(optarg);
 579                         break;
 580                 case 'B':
 581                         origprae = xstrdup(optarg);
 582                         break;
 583                 case 'c':
 584                         diff_type = CONTEXT_DIFF;
 585                         break;
 586                 case 'C':
 587                         check_only = true;
 588                         break;
 589                 case 'd':
 590                         if (chdir(optarg) < 0)
 591                                 pfatal("can't cd to %s", optarg);
 592                         break;
 593                 case 'D':
 594                         do_defines = true;
 595                         if (!isalpha((unsigned char)*optarg) && *optarg != '_')
 596                                 fatal("argument to -D is not an identifier\n");
 597                         snprintf(if_defined, sizeof if_defined,
 598                             "#ifdef %s\n", optarg);
 599                         snprintf(not_defined, sizeof not_defined,
 600                             "#ifndef %s\n", optarg);
 601                         snprintf(end_defined, sizeof end_defined,
 602                             "#endif /* %s */\n", optarg);
 603                         break;
 604                 case 'e':
 605                         diff_type = ED_DIFF;
 606                         break;
 607                 case 'E':
 608                         remove_empty_files = true;
 609                         break;
 610                 case 'f':
 611                         force = true;
 612                         break;
 613                 case 'F':
 614                         maxfuzz = atoi(optarg);
 615                         break;
 616                 case 'i':
 617                         if (++filec == MAXFILEC)
 618                                 fatal("too many file arguments\n");
 619                         filearg[filec] = xstrdup(optarg);
 620                         break;
 621                 case 'l':
 622                         canonicalize = true;
 623                         break;
 624                 case 'n':
 625                         diff_type = NORMAL_DIFF;
 626                         break;
 627                 case 'N':
 628                         noreverse = true;
 629                         break;
 630                 case 'o':
 631                         outname = xstrdup(optarg);
 632                         break;
 633                 case 'p':
 634                         strippath = atoi(optarg);
 635                         break;
 636                 case 'r':
 637                         if (strlcpy(rejname, optarg,
 638                             sizeof(rejname)) >= sizeof(rejname))
 639                                 fatal("argument for -r is too long\n");
 640                         break;
 641                 case 'R':
 642                         reverse = true;
 643                         reverse_flag_specified = true;
 644                         break;
 645                 case 's':
 646                         verbose = false;
 647                         break;
 648                 case 't':
 649                         batch = true;
 650                         break;
 651                 case 'u':
 652                         diff_type = UNI_DIFF;
 653                         break;
 654                 case 'v':
 655                         version();
 656                         break;
 657                 case 'V':
 658                         backup_type = get_version(optarg);
 659                         Vflag = true;
 660                         break;
 661 #ifdef DEBUGGING
 662                 case 'x':
 663                         debug = atoi(optarg);
 664                         break;
 665 #endif
 666                 default:
 667                         if (ch != '\0')
 668                                 usage();
 669                         break;
 670                 }
 671         }
 672         Argc -= optind;
 673         Argv += optind;
 674
 675         if (Argc > 0) {
 676                 filearg[0] = xstrdup(*Argv++);
 677                 Argc--;
 678                 while (Argc > 0) {
 679                         if (++filec == MAXFILEC)
 680                                 fatal("too many file arguments\n");
 681                         filearg[filec] = xstrdup(*Argv++);
 682                         Argc--;
 683                 }
 684         }
 685
 686         if (getenv("POSIXLY_CORRECT") != NULL)
 687                 posix = 1;
 688 }
 689
 690 static void
 691 usage(void)
 692 {
 693         fprintf(stderr,
 694 "usage: patch [-bCcEeflNnRstuv] [-B backup-prefix] [-D symbol] [-d directory]\n"
 695 "             [-F max-fuzz] [-i patchfile] [-o out-file] [-p strip-count]\n"
 696 "             [-r rej-name] [-V t | nil | never | none] [-x number]\n"
 697 "             [-z backup-ext] [--posix] [origfile [patchfile]]\n"
 698 "       patch <patchfile\n");
 699         my_exit(EXIT_FAILURE);
 700 }
 701
 702 /*
 703  * Attempt to find the right place to apply this hunk of patch.
 704  */
 705 static LINENUM
 706 locate_hunk(LINENUM fuzz)
 707 {
 708         LINENUM first_guess = pch_first() + last_offset;
 709         LINENUM offset;
 710         LINENUM pat_lines = pch_ptrn_lines();
 711         LINENUM max_pos_offset = input_lines - first_guess - pat_lines + 1;
 712         LINENUM max_neg_offset = first_guess - last_frozen_line - 1 + pch_context();
 713
 714         if (pat_lines == 0) {           /* null range matches always */
 715                 if (verbose && fuzz == 0 && (diff_type == CONTEXT_DIFF
 716                     || diff_type == NEW_CONTEXT_DIFF
 717                     || diff_type == UNI_DIFF)) {
 718                         say("Empty context always matches.\n");
 719                 }
 720                 return (first_guess);
 721         }
 722         if (max_neg_offset >= first_guess)      /* do not try lines < 0 */
 723                 max_neg_offset = first_guess - 1;
 724         if (first_guess <= input_lines && patch_match(first_guess, 0, fuzz))
 725                 return first_guess;
 726         for (offset = 1; ; offset++) {
 727                 bool    check_after = (offset <= max_pos_offset);
 728                 bool    check_before = (offset <= max_neg_offset);
 729
 730                 if (check_after && patch_match(first_guess, offset, fuzz)) {
 731 #ifdef DEBUGGING
 732                         if (debug & 1)
 733                                 say("Offset changing from %ld to %ld\n",
 734                                     last_offset, offset);
 735 #endif
 736                         last_offset = offset;
 737                         return first_guess + offset;
 738                 } else if (check_before && patch_match(first_guess, -offset, fuzz)) {
 739 #ifdef DEBUGGING
 740                         if (debug & 1)
 741                                 say("Offset changing from %ld to %ld\n",
 742                                     last_offset, -offset);
 743 #endif
 744                         last_offset = -offset;
 745                         return first_guess - offset;
 746                 } else if (!check_before && !check_after)
 747                         return 0;
 748         }
 749 }
 750
 751 /* We did not find the pattern, dump out the hunk so they can handle it. */
 752
 753 static void
 754 abort_context_hunk(void)
 755 {
 756         LINENUM i;
 757         const LINENUM   pat_end = pch_end();
 758         /*
 759          * add in last_offset to guess the same as the previous successful
 760          * hunk
 761          */
 762         const LINENUM   oldfirst = pch_first() + last_offset;
 763         const LINENUM   newfirst = pch_newfirst() + last_offset;
 764         const LINENUM   oldlast = oldfirst + pch_ptrn_lines() - 1;
 765         const LINENUM   newlast = newfirst + pch_repl_lines() - 1;
 766         const char      *stars = (diff_type >= NEW_CONTEXT_DIFF ? " ****" : "");
 767         const char      *minuses = (diff_type >= NEW_CONTEXT_DIFF ? " ----" : " -----");
 768
 769         fprintf(rejfp, "***************\n");
 770         for (i = 0; i <= pat_end; i++) {
 771                 switch (pch_char(i)) {
 772                 case '*':
 773                         if (oldlast < oldfirst)
 774                                 fprintf(rejfp, "*** 0%s\n", stars);
 775                         else if (oldlast == oldfirst)
 776                                 fprintf(rejfp, "*** %ld%s\n", oldfirst, stars);
 777                         else
 778                                 fprintf(rejfp, "*** %ld,%ld%s\n", oldfirst,
 779                                     oldlast, stars);
 780                         break;
 781                 case '=':
 782                         if (newlast < newfirst)
 783                                 fprintf(rejfp, "--- 0%s\n", minuses);
 784                         else if (newlast == newfirst)
 785                                 fprintf(rejfp, "--- %ld%s\n", newfirst, minuses);
 786                         else
 787                                 fprintf(rejfp, "--- %ld,%ld%s\n", newfirst,
 788                                     newlast, minuses);
 789                         break;
 790                 case '\n':
 791                         fprintf(rejfp, "%s", pfetch(i));
 792                         break;
 793                 case ' ':
 794                 case '-':
 795                 case '+':
 796                 case '!':
 797                         fprintf(rejfp, "%c %s", pch_char(i), pfetch(i));
 798                         break;
 799                 default:
 800                         fatal("fatal internal error in abort_context_hunk\n");
 801                 }
 802         }
 803 }
 804
 805 static void
 806 rej_line(int ch, LINENUM i)
 807 {
 808         size_t len;
 809         const char *line = pfetch(i);
 810
 811         len = strlen(line);
 812
 813         fprintf(rejfp, "%c%s", ch, line);
 814         if (len == 0 || line[len - 1] != '\n') {
 815                 if (len >= USHRT_MAX)
 816                         fprintf(rejfp, "\n\\ Line too long\n");
 817                 else
 818                         fprintf(rejfp, "\n\\ No newline at end of line\n");
 819         }
 820 }
 821
 822 static void
 823 abort_hunk(void)
 824 {
 825         LINENUM         i, j, split;
 826         int             ch1, ch2;
 827         const LINENUM   pat_end = pch_end();
 828         const LINENUM   oldfirst = pch_first() + last_offset;
 829         const LINENUM   newfirst = pch_newfirst() + last_offset;
 830
 831         if (diff_type != UNI_DIFF) {
 832                 abort_context_hunk();
 833                 return;
 834         }
 835         split = -1;
 836         for (i = 0; i <= pat_end; i++) {
 837                 if (pch_char(i) == '=') {
 838                         split = i;
 839                         break;
 840                 }
 841         }
 842         if (split == -1) {
 843                 fprintf(rejfp, "malformed hunk: no split found\n");
 844                 return;
 845         }
 846         i = 0;
 847         j = split + 1;
 848         fprintf(rejfp, "@@ -%ld,%ld +%ld,%ld @@\n",
 849             pch_ptrn_lines() ? oldfirst : 0,
 850             pch_ptrn_lines(), newfirst, pch_repl_lines());
 851         while (i < split || j <= pat_end) {
 852                 ch1 = i < split ? pch_char(i) : -1;
 853                 ch2 = j <= pat_end ? pch_char(j) : -1;
 854                 if (ch1 == '-') {
 855                         rej_line('-', i);
 856                         i++;
 857                 } else if (ch1 == ' ' && ch2 == ' ') {
 858                         rej_line(' ', i);
 859                         i++;
 860                         j++;
 861                 } else if (ch1 == '!' && ch2 == '!') {
 862                         while (i < split && ch1 == '!') {
 863                                 rej_line('-', i);
 864                                 i++;
 865                                 ch1 = i < split ? pch_char(i) : -1;
 866                         }
 867                         while (j <= pat_end && ch2 == '!') {
 868                                 rej_line('+', j);
 869                                 j++;
 870                                 ch2 = j <= pat_end ? pch_char(j) : -1;
 871                         }
 872                 } else if (ch1 == '*') {
 873                         i++;
 874                 } else if (ch2 == '+' || ch2 == ' ') {
 875                         rej_line(ch2, j);
 876                         j++;
 877                 } else {
 878                         fprintf(rejfp, "internal error on (%ld %ld %ld)\n",
 879                             i, split, j);
 880                         rej_line(ch1, i);
 881                         rej_line(ch2, j);
 882                         return;
 883                 }
 884         }
 885 }
 886
 887 /* We found where to apply it (we hope), so do it. */
 888
 889 static void
 890 apply_hunk(LINENUM where)
 891 {
 892         LINENUM         old = 1;
 893         const LINENUM   lastline = pch_ptrn_lines();
 894         LINENUM         new = lastline + 1;
 895 #define OUTSIDE 0
 896 #define IN_IFNDEF 1
 897 #define IN_IFDEF 2
 898 #define IN_ELSE 3
 899         int             def_state = OUTSIDE;
 900         const LINENUM   pat_end = pch_end();
 901
 902         where--;
 903         while (pch_char(new) == '=' || pch_char(new) == '\n')
 904                 new++;
 905
 906         while (old <= lastline) {
 907                 if (pch_char(old) == '-') {
 908                         copy_till(where + old - 1, false);
 909                         if (do_defines) {
 910                                 if (def_state == OUTSIDE) {
 911                                         fputs(not_defined, ofp);
 912                                         def_state = IN_IFNDEF;
 913                                 } else if (def_state == IN_IFDEF) {
 914                                         fputs(else_defined, ofp);
 915                                         def_state = IN_ELSE;
 916                                 }
 917                                 fputs(pfetch(old), ofp);
 918                         }
 919                         last_frozen_line++;
 920                         old++;
 921                 } else if (new > pat_end) {
 922                         break;
 923                 } else if (pch_char(new) == '+') {
 924                         copy_till(where + old - 1, false);
 925                         if (do_defines) {
 926                                 if (def_state == IN_IFNDEF) {
 927                                         fputs(else_defined, ofp);
 928                                         def_state = IN_ELSE;
 929                                 } else if (def_state == OUTSIDE) {
 930                                         fputs(if_defined, ofp);
 931                                         def_state = IN_IFDEF;
 932                                 }
 933                         }
 934                         fputs(pfetch(new), ofp);
 935                         new++;
 936                 } else if (pch_char(new) != pch_char(old)) {
 937                         say("Out-of-sync patch, lines %ld,%ld--mangled text or line numbers, maybe?\n",
 938                             pch_hunk_beg() + old,
 939                             pch_hunk_beg() + new);
 940 #ifdef DEBUGGING
 941                         say("oldchar = '%c', newchar = '%c'\n",
 942                             pch_char(old), pch_char(new));
 943 #endif
 944                         my_exit(2);
 945                 } else if (pch_char(new) == '!') {
 946                         copy_till(where + old - 1, false);
 947                         if (do_defines) {
 948                                 fputs(not_defined, ofp);
 949                                 def_state = IN_IFNDEF;
 950                         }
 951                         while (pch_char(old) == '!') {
 952                                 if (do_defines) {
 953                                         fputs(pfetch(old), ofp);
 954                                 }
 955                                 last_frozen_line++;
 956                                 old++;
 957                         }
 958                         if (do_defines) {
 959                                 fputs(else_defined, ofp);
 960                                 def_state = IN_ELSE;
 961                         }
 962                         while (pch_char(new) == '!') {
 963                                 fputs(pfetch(new), ofp);
 964                                 new++;
 965                         }
 966                 } else {
 967                         if (pch_char(new) != ' ')
 968                                 fatal("Internal error: expected ' '\n");
 969                         old++;
 970                         new++;
 971                         if (do_defines && def_state != OUTSIDE) {
 972                                 fputs(end_defined, ofp);
 973                                 def_state = OUTSIDE;
 974                         }
 975                 }
 976         }
 977         if (new <= pat_end && pch_char(new) == '+') {
 978                 copy_till(where + old - 1, false);
 979                 if (do_defines) {
 980                         if (def_state == OUTSIDE) {
 981                                 fputs(if_defined, ofp);
 982                                 def_state = IN_IFDEF;
 983                         } else if (def_state == IN_IFNDEF) {
 984                                 fputs(else_defined, ofp);
 985                                 def_state = IN_ELSE;
 986                         }
 987                 }
 988                 while (new <= pat_end && pch_char(new) == '+') {
 989                         fputs(pfetch(new), ofp);
 990                         new++;
 991                 }
 992         }
 993         if (do_defines && def_state != OUTSIDE) {
 994                 fputs(end_defined, ofp);
 995         }
 996 }
 997
 998 /*
 999  * Open the new file.
1000  */
1001 static void
1002 init_output(const char *name)
1003 {
1004         ofp = fopen(name, "w");
1005         if (ofp == NULL)
1006                 pfatal("can't create %s", name);
1007 }
1008
1009 /*
1010  * Open a file to put hunks we can't locate.
1011  */
1012 static void
1013 init_reject(const char *name)
1014 {
1015         rejfp = fopen(name, "w");
1016         if (rejfp == NULL)
1017                 pfatal("can't create %s", name);
1018 }
1019
1020 /*
1021  * Copy input file to output, up to wherever hunk is to be applied.
1022  * If endoffile is true, treat the last line specially since it may
1023  * lack a newline.
1024  */
1025 static void
1026 copy_till(LINENUM lastline, bool endoffile)
1027 {
1028         if (last_frozen_line > lastline)
1029                 fatal("misordered hunks! output would be garbled\n");
1030         while (last_frozen_line < lastline) {
1031                 if (++last_frozen_line == lastline && endoffile)
1032                         dump_line(last_frozen_line, !last_line_missing_eol);
1033                 else
1034                         dump_line(last_frozen_line, true);
1035         }
1036 }
1037
1038 /*
1039  * Finish copying the input file to the output file.
1040  */
1041 static bool
1042 spew_output(void)
1043 {
1044         int rv;
1045
1046 #ifdef DEBUGGING
1047         if (debug & 256)
1048                 say("il=%ld lfl=%ld\n", input_lines, last_frozen_line);
1049 #endif
1050         if (input_lines)
1051                 copy_till(input_lines, true);   /* dump remainder of file */
1052         rv = ferror(ofp) == 0 && fclose(ofp) == 0;
1053         ofp = NULL;
1054         return rv;
1055 }
1056
1057 /*
1058  * Copy one line from input to output.
1059  */
1060 static void
1061 dump_line(LINENUM line, bool write_newline)
1062 {
1063         char    *s;
1064
1065         s = ifetch(line, 0);
1066         if (s == NULL)
1067                 return;
1068         /* Note: string is not NUL terminated. */
1069         for (; *s != '\n'; s++)
1070                 putc(*s, ofp);
1071         if (write_newline)
1072                 putc('\n', ofp);
1073 }
1074
1075 /*
1076  * Does the patch pattern match at line base+offset?
1077  */
1078 static bool
1079 patch_match(LINENUM base, LINENUM offset, LINENUM fuzz)
1080 {
1081         LINENUM         pline = 1 + fuzz;
1082         LINENUM         iline;
1083         LINENUM         pat_lines = pch_ptrn_lines() - fuzz;
1084         const char      *ilineptr;
1085         const char      *plineptr;
1086         unsigned short  plinelen;
1087
1088         /* Patch does not match if we don't have any more context to use */
1089         if (pline > pat_lines)
1090                 return false;
1091         for (iline = base + offset + fuzz; pline <= pat_lines; pline++, iline++) {
1092                 ilineptr = ifetch(iline, offset >= 0);
1093                 if (ilineptr == NULL)
1094                         return false;
1095                 plineptr = pfetch(pline);
1096                 plinelen = pch_line_len(pline);
1097                 if (canonicalize) {
1098                         if (!similar(ilineptr, plineptr, plinelen))
1099                                 return false;
1100                 } else if (strnNE(ilineptr, plineptr, plinelen))
1101                         return false;
1102                 if (iline == input_lines) {
1103                         /*
1104                          * We are looking at the last line of the file.
1105                          * If the file has no eol, the patch line should
1106                          * not have one either and vice-versa. Note that
1107                          * plinelen > 0.
1108                          */
1109                         if (last_line_missing_eol) {
1110                                 if (plineptr[plinelen - 1] == '\n')
1111                                         return false;
1112                         } else {
1113                                 if (plineptr[plinelen - 1] != '\n')
1114                                         return false;
1115                         }
1116                 }
1117         }
1118         return true;
1119 }
1120
1121 /*
1122  * Do two lines match with canonicalized white space?
1123  */
1124 static bool
1125 similar(const char *a, const char *b, int len)
1126 {
1127         while (len) {
1128                 if (isspace((unsigned char)*b)) {       /* whitespace (or \n) to match? */
1129                         if (!isspace((unsigned char)*a))        /* no corresponding whitespace? */
1130                                 return false;
1131                         while (len && isspace((unsigned char)*b) && *b != '\n')
1132                                 b++, len--;     /* skip pattern whitespace */
1133                         while (isspace((unsigned char)*a) && *a != '\n')
1134                                 a++;    /* skip target whitespace */
1135                         if (*a == '\n' || *b == '\n')
1136                                 return (*a == *b);      /* should end in sync */
1137                 } else if (*a++ != *b++)        /* match non-whitespace chars */
1138                         return false;
1139                 else
1140                         len--;  /* probably not necessary */
1141         }
1142         return true;            /* actually, this is not reached */
1143         /* since there is always a \n */
1144 }
1145
1146 static bool
1147 handle_creation(bool out_existed, bool *remove)
1148 {
1149         bool reverse_seen;
1150
1151         reverse_seen = false;
1152         if (reverse && out_existed) {
1153                 /*
1154                  * If the patch creates the file and we're reversing the patch,
1155                  * then we need to indicate to the patch processor that it's OK
1156                  * to remove this file.
1157                  */
1158                 *remove = true;
1159         } else if (!reverse && out_existed) {
1160                 /*
1161                  * Otherwise, we need to blow the horn because the patch appears
1162                  * to be reversed/already applied.  For non-batch jobs, we'll
1163                  * prompt to figure out what we should be trying to do to raise
1164                  * awareness of the issue.  batch (-t) processing suppresses the
1165                  * questions and just assumes that we're reversed if it looks
1166                  * like we are, which is always the case if we've reached this
1167                  * branch.
1168                  */
1169                 if (force) {
1170                         skip_rest_of_patch = true;
1171                         return (false);
1172                 }
1173                 if (noreverse) {
1174                         /* If -N is supplied, however, we bail out/ignore. */
1175                         say("Ignoring previously applied (or reversed) patch.\n");
1176                         skip_rest_of_patch = true;
1177                         return (false);
1178                 }
1179
1180                 /* Unreversed... suspicious if the file existed. */
1181                 if (!pch_swap())
1182                         fatal("lost hunk on alloc error!\n");
1183
1184                 reverse = !reverse;
1185
1186                 if (batch) {
1187                         if (verbose)
1188                                 say("Patch creates file that already exists, %s %seversed",
1189                                     reverse ? "Assuming" : "Ignoring",
1190                                     reverse ? "R" : "Unr");
1191                 } else {
1192                         ask("Patch creates file that already exists!  %s -R? [y] ",
1193                             reverse ? "Assume" : "Ignore");
1194
1195                         if (*buf == 'n') {
1196                                 ask("Apply anyway? [n]");
1197                                 if (*buf != 'y')
1198                                         /* Don't apply; error out. */
1199                                         skip_rest_of_patch = true;
1200                                 else
1201                                         /* Attempt to apply. */
1202                                         reverse_seen = true;
1203                                 reverse = !reverse;
1204                                 if (!pch_swap())
1205                                         fatal("lost hunk on alloc error!\n");
1206                         } else {
1207                                 /*
1208                                  * They've opted to assume -R; effectively the
1209                                  * same as the first branch in this function,
1210                                  * but the decision is here rather than in a
1211                                  * prior patch/hunk as in that branch.
1212                                  */
1213                                 *remove = true;
1214                         }
1215                 }
1216         }
1217
1218         /*
1219          * The return value indicates if we offered a chance to reverse but the
1220          * user declined.  This keeps the main patch processor in the loop since
1221          * we've taken this out of the normal flow of hunk processing to
1222          * simplify logic a little bit.
1223          */
1224         return (reverse_seen);
1225 }