usr.bin/patch/pch.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: pch.c,v 1.43 2014/11/18 17:03:35 tobias Exp $
  27  * $FreeBSD$
  28  */
  29
  30 #include <sys/types.h>
  31 #include <sys/stat.h>
  32
  33 #include <ctype.h>
  34 #include <libgen.h>
  35 #include <limits.h>
  36 #include <stdint.h>
  37 #include <stdio.h>
  38 #include <stdlib.h>
  39 #include <string.h>
  40 #include <unistd.h>
  41
  42 #include "common.h"
  43 #include "util.h"
  44 #include "pch.h"
  45 #include "pathnames.h"
  46
  47 /* Patch (diff listing) abstract type. */
  48
  49 static off_t    p_filesize;     /* size of the patch file */
  50 static LINENUM  p_first;        /* 1st line number */
  51 static LINENUM  p_newfirst;     /* 1st line number of replacement */
  52 static LINENUM  p_ptrn_lines;   /* # lines in pattern */
  53 static LINENUM  p_repl_lines;   /* # lines in replacement text */
  54 static LINENUM  p_end = -1;     /* last line in hunk */
  55 static LINENUM  p_max;          /* max allowed value of p_end */
  56 static LINENUM  p_context = 3;  /* # of context lines */
  57 static LINENUM  p_input_line = 0;       /* current line # from patch file */
  58 static char     **p_line = NULL;/* the text of the hunk */
  59 static unsigned short   *p_len = NULL; /* length of each line */
  60 static char     *p_char = NULL; /* +, -, and ! */
  61 static int      hunkmax = INITHUNKMAX;  /* size of above arrays to begin with */
  62 static int      p_indent;       /* indent to patch */
  63 static off_t    p_base;         /* where to intuit this time */
  64 static LINENUM  p_bline;        /* line # of p_base */
  65 static off_t    p_start;        /* where intuit found a patch */
  66 static LINENUM  p_sline;        /* and the line number for it */
  67 static LINENUM  p_hunk_beg;     /* line number of current hunk */
  68 static LINENUM  p_efake = -1;   /* end of faked up lines--don't free */
  69 static LINENUM  p_bfake = -1;   /* beg of faked up lines */
  70 static FILE     *pfp = NULL;    /* patch file pointer */
  71 static char     *bestguess = NULL;      /* guess at correct filename */
  72
  73 static void     grow_hunkmax(void);
  74 static int      intuit_diff_type(void);
  75 static void     next_intuit_at(off_t, LINENUM);
  76 static void     skip_to(off_t, LINENUM);
  77 static size_t   pgets(bool _do_indent);
  78 static char     *best_name(const struct file_name *, bool);
  79 static char     *posix_name(const struct file_name *, bool);
  80 static size_t   num_components(const char *);
  81 static LINENUM  strtolinenum(char *, char **);
  82
  83 /*
  84  * Prepare to look for the next patch in the patch file.
  85  */
  86 void
  87 re_patch(void)
  88 {
  89         p_first = 0;
  90         p_newfirst = 0;
  91         p_ptrn_lines = 0;
  92         p_repl_lines = 0;
  93         p_end = (LINENUM) - 1;
  94         p_max = 0;
  95         p_indent = 0;
  96 }
  97
  98 /*
  99  * Open the patch file at the beginning of time.
 100  */
 101 void
 102 open_patch_file(const char *filename)
 103 {
 104         struct stat filestat;
 105         int nr, nw;
 106
 107         if (filename == NULL || *filename == '\0' || strEQ(filename, "-")) {
 108                 pfp = fopen(TMPPATNAME, "w");
 109                 if (pfp == NULL)
 110                         pfatal("can't create %s", TMPPATNAME);
 111                 while ((nr = fread(buf, 1, buf_size, stdin)) > 0) {
 112                         nw = fwrite(buf, 1, nr, pfp);
 113                         if (nr != nw)
 114                                 pfatal("write error to %s", TMPPATNAME);
 115                 }
 116                 if (ferror(pfp) || fclose(pfp))
 117                         pfatal("can't write %s", TMPPATNAME);
 118                 filename = TMPPATNAME;
 119         }
 120         pfp = fopen(filename, "r");
 121         if (pfp == NULL)
 122                 pfatal("patch file %s not found", filename);
 123         if (fstat(fileno(pfp), &filestat))
 124                 pfatal("can't stat %s", filename);
 125         p_filesize = filestat.st_size;
 126         next_intuit_at(0, 1L);  /* start at the beginning */
 127         set_hunkmax();
 128 }
 129
 130 /*
 131  * Make sure our dynamically realloced tables are malloced to begin with.
 132  */
 133 void
 134 set_hunkmax(void)
 135 {
 136         if (p_line == NULL)
 137                 p_line = malloc(hunkmax * sizeof(char *));
 138         if (p_len == NULL)
 139                 p_len = malloc(hunkmax * sizeof(unsigned short));
 140         if (p_char == NULL)
 141                 p_char = malloc(hunkmax * sizeof(char));
 142 }
 143
 144 /*
 145  * Enlarge the arrays containing the current hunk of patch.
 146  */
 147 static void
 148 grow_hunkmax(void)
 149 {
 150         int new_hunkmax = hunkmax * 2;
 151
 152         if (p_line == NULL || p_len == NULL || p_char == NULL)
 153                 fatal("Internal memory allocation error\n");
 154
 155         p_line = reallocf(p_line, new_hunkmax * sizeof(char *));
 156         p_len = reallocf(p_len, new_hunkmax * sizeof(unsigned short));
 157         p_char = reallocf(p_char, new_hunkmax * sizeof(char));
 158
 159         if (p_line != NULL && p_len != NULL && p_char != NULL) {
 160                 hunkmax = new_hunkmax;
 161                 return;
 162         }
 163
 164         if (!using_plan_a)
 165                 fatal("out of memory\n");
 166         out_of_mem = true;      /* whatever is null will be allocated again */
 167                                 /* from within plan_a(), of all places */
 168 }
 169
 170 /* True if the remainder of the patch file contains a diff of some sort. */
 171
 172 bool
 173 there_is_another_patch(void)
 174 {
 175         bool exists = false;
 176
 177         if (p_base != 0 && p_base >= p_filesize) {
 178                 if (verbose)
 179                         say("done\n");
 180                 return false;
 181         }
 182         if (verbose)
 183                 say("Hmm...");
 184         diff_type = intuit_diff_type();
 185         if (!diff_type) {
 186                 if (p_base != 0) {
 187                         if (verbose)
 188                                 say("  Ignoring the trailing garbage.\ndone\n");
 189                 } else
 190                         say("  I can't seem to find a patch in there anywhere.\n");
 191                 return false;
 192         }
 193         if (verbose)
 194                 say("  %sooks like %s to me...\n",
 195                     (p_base == 0 ? "L" : "The next patch l"),
 196                     diff_type == UNI_DIFF ? "a unified diff" :
 197                     diff_type == CONTEXT_DIFF ? "a context diff" :
 198                 diff_type == NEW_CONTEXT_DIFF ? "a new-style context diff" :
 199                     diff_type == NORMAL_DIFF ? "a normal diff" :
 200                     "an ed script");
 201         if (p_indent && verbose)
 202                 say("(Patch is indented %d space%s.)\n", p_indent,
 203                     p_indent == 1 ? "" : "s");
 204         skip_to(p_start, p_sline);
 205         while (filearg[0] == NULL) {
 206                 if (force || batch) {
 207                         say("No file to patch.  Skipping...\n");
 208                         filearg[0] = xstrdup(bestguess);
 209                         skip_rest_of_patch = true;
 210                         return true;
 211                 }
 212                 ask("File to patch: ");
 213                 if (*buf != '\n') {
 214                         free(bestguess);
 215                         bestguess = xstrdup(buf);
 216                         filearg[0] = fetchname(buf, &exists, 0);
 217                 }
 218                 if (!exists) {
 219                         int def_skip = *bestguess == '\0';
 220                         ask("No file found--skip this patch? [%c] ",
 221                             def_skip  ? 'y' : 'n');
 222                         if (*buf == 'n' || (!def_skip && *buf != 'y'))
 223                                 continue;
 224                         if (verbose)
 225                                 say("Skipping patch...\n");
 226                         free(filearg[0]);
 227                         filearg[0] = fetchname(bestguess, &exists, 0);
 228                         skip_rest_of_patch = true;
 229                         return true;
 230                 }
 231         }
 232         return true;
 233 }
 234
 235 static void
 236 p4_fetchname(struct file_name *name, char *str)
 237 {
 238         char *t, *h;
 239
 240         /* Skip leading whitespace. */
 241         while (isspace((unsigned char)*str))
 242                 str++;
 243
 244         /* Remove the file revision number. */
 245         for (t = str, h = NULL; *t != '\0' && !isspace((unsigned char)*t); t++)
 246                 if (*t == '#')
 247                         h = t;
 248         if (h != NULL)
 249                 *h = '\0';
 250
 251         name->path = fetchname(str, &name->exists, strippath);
 252 }
 253
 254 /* Determine what kind of diff is in the remaining part of the patch file. */
 255
 256 static int
 257 intuit_diff_type(void)
 258 {
 259         off_t   this_line = 0, previous_line;
 260         off_t   first_command_line = -1;
 261         LINENUM fcl_line = -1;
 262         bool    last_line_was_command = false, this_is_a_command = false;
 263         bool    stars_last_line = false, stars_this_line = false;
 264         char    *s, *t;
 265         int     indent, retval;
 266         struct file_name names[MAX_FILE];
 267         int     piece_of_git = 0;
 268
 269         memset(names, 0, sizeof(names));
 270         ok_to_create_file = false;
 271         fseeko(pfp, p_base, SEEK_SET);
 272         p_input_line = p_bline - 1;
 273         for (;;) {
 274                 previous_line = this_line;
 275                 last_line_was_command = this_is_a_command;
 276                 stars_last_line = stars_this_line;
 277                 this_line = ftello(pfp);
 278                 indent = 0;
 279                 p_input_line++;
 280                 if (pgets(false) == 0) {
 281                         if (first_command_line >= 0) {
 282                                 /* nothing but deletes!? */
 283                                 p_start = first_command_line;
 284                                 p_sline = fcl_line;
 285                                 retval = ED_DIFF;
 286                                 goto scan_exit;
 287                         } else {
 288                                 p_start = this_line;
 289                                 p_sline = p_input_line;
 290                                 retval = 0;
 291                                 goto scan_exit;
 292                         }
 293                 }
 294                 for (s = buf; *s == ' ' || *s == '\t' || *s == 'X'; s++) {
 295                         if (*s == '\t')
 296                                 indent += 8 - (indent % 8);
 297                         else
 298                                 indent++;
 299                 }
 300                 for (t = s; isdigit((unsigned char)*t) || *t == ','; t++)
 301                         ;
 302                 this_is_a_command = (isdigit((unsigned char)*s) &&
 303                     (*t == 'd' || *t == 'c' || *t == 'a'));
 304                 if (first_command_line < 0 && this_is_a_command) {
 305                         first_command_line = this_line;
 306                         fcl_line = p_input_line;
 307                         p_indent = indent;      /* assume this for now */
 308                 }
 309                 if (!stars_last_line && strnEQ(s, "*** ", 4))
 310                         names[OLD_FILE].path = fetchname(s + 4,
 311                             &names[OLD_FILE].exists, strippath);
 312                 else if (strnEQ(s, "--- ", 4)) {
 313                         size_t off = 4;
 314                         if (piece_of_git && strippath == 957 &&
 315                             strnEQ(s, "--- a/", 6))
 316                                 off = 6;
 317                         names[NEW_FILE].path = fetchname(s + off,
 318                             &names[NEW_FILE].exists, strippath);
 319                 } else if (strnEQ(s, "+++ ", 4)) {
 320                         /* pretend it is the old name */
 321                         size_t off = 4;
 322                         if (piece_of_git && strippath == 957 &&
 323                             strnEQ(s, "+++ b/", 6))
 324                                 off = 6;
 325                         names[OLD_FILE].path = fetchname(s + off,
 326                             &names[OLD_FILE].exists, strippath);
 327                 } else if (strnEQ(s, "Index:", 6))
 328                         names[INDEX_FILE].path = fetchname(s + 6,
 329                             &names[INDEX_FILE].exists, strippath);
 330                 else if (strnEQ(s, "Prereq:", 7)) {
 331                         for (t = s + 7; isspace((unsigned char)*t); t++)
 332                                 ;
 333                         revision = xstrdup(t);
 334                         for (t = revision;
 335                              *t && !isspace((unsigned char)*t); t++)
 336                                 ;
 337                         *t = '\0';
 338                         if (*revision == '\0') {
 339                                 free(revision);
 340                                 revision = NULL;
 341                         }
 342                 } else if (strnEQ(s, "diff --git a/", 13)) {
 343                         /* Git-style diffs. */
 344                         piece_of_git = 1;
 345                 } else if (strnEQ(s, "==== ", 5)) {
 346                         /* Perforce-style diffs. */
 347                         if ((t = strstr(s + 5, " - ")) != NULL)
 348                                 p4_fetchname(&names[NEW_FILE], t + 3);
 349                         p4_fetchname(&names[OLD_FILE], s + 5);
 350                 }
 351                 if ((!diff_type || diff_type == ED_DIFF) &&
 352                     first_command_line >= 0 &&
 353                     strEQ(s, ".\n")) {
 354                         p_indent = indent;
 355                         p_start = first_command_line;
 356                         p_sline = fcl_line;
 357                         retval = ED_DIFF;
 358                         goto scan_exit;
 359                 }
 360                 if ((!diff_type || diff_type == UNI_DIFF) && strnEQ(s, "@@ -", 4)) {
 361                         if (strnEQ(s + 4, "0,0", 3))
 362                                 ok_to_create_file = true;
 363                         p_indent = indent;
 364                         p_start = this_line;
 365                         p_sline = p_input_line;
 366                         retval = UNI_DIFF;
 367                         goto scan_exit;
 368                 }
 369                 stars_this_line = strnEQ(s, "********", 8);
 370                 if ((!diff_type || diff_type == CONTEXT_DIFF) && stars_last_line &&
 371                     strnEQ(s, "*** ", 4)) {
 372                         if (strtolinenum(s + 4, &s) == 0)
 373                                 ok_to_create_file = true;
 374                         /*
 375                          * If this is a new context diff the character just
 376                          * at the end of the line is a '*'.
 377                          */
 378                         while (*s && *s != '\n')
 379                                 s++;
 380                         p_indent = indent;
 381                         p_start = previous_line;
 382                         p_sline = p_input_line - 1;
 383                         retval = (*(s - 1) == '*' ? NEW_CONTEXT_DIFF : CONTEXT_DIFF);
 384                         goto scan_exit;
 385                 }
 386                 if ((!diff_type || diff_type == NORMAL_DIFF) &&
 387                     last_line_was_command &&
 388                     (strnEQ(s, "< ", 2) || strnEQ(s, "> ", 2))) {
 389                         p_start = previous_line;
 390                         p_sline = p_input_line - 1;
 391                         p_indent = indent;
 392                         retval = NORMAL_DIFF;
 393                         goto scan_exit;
 394                 }
 395         }
 396 scan_exit:
 397         if (retval == UNI_DIFF) {
 398                 /* unswap old and new */
 399                 struct file_name tmp = names[OLD_FILE];
 400                 names[OLD_FILE] = names[NEW_FILE];
 401                 names[NEW_FILE] = tmp;
 402         }
 403         if (filearg[0] == NULL) {
 404                 if (posix)
 405                         filearg[0] = posix_name(names, ok_to_create_file);
 406                 else {
 407                         /* Ignore the Index: name for context diffs, like GNU */
 408                         if (names[OLD_FILE].path != NULL ||
 409                             names[NEW_FILE].path != NULL) {
 410                                 free(names[INDEX_FILE].path);
 411                                 names[INDEX_FILE].path = NULL;
 412                         }
 413                         filearg[0] = best_name(names, ok_to_create_file);
 414                 }
 415         }
 416
 417         free(bestguess);
 418         bestguess = NULL;
 419         if (filearg[0] != NULL)
 420                 bestguess = xstrdup(filearg[0]);
 421         else if (!ok_to_create_file) {
 422                 /*
 423                  * We don't want to create a new file but we need a
 424                  * filename to set bestguess.  Avoid setting filearg[0]
 425                  * so the file is not created automatically.
 426                  */
 427                 if (posix)
 428                         bestguess = posix_name(names, true);
 429                 else
 430                         bestguess = best_name(names, true);
 431         }
 432         free(names[OLD_FILE].path);
 433         free(names[NEW_FILE].path);
 434         free(names[INDEX_FILE].path);
 435         return retval;
 436 }
 437
 438 /*
 439  * Remember where this patch ends so we know where to start up again.
 440  */
 441 static void
 442 next_intuit_at(off_t file_pos, LINENUM file_line)
 443 {
 444         p_base = file_pos;
 445         p_bline = file_line;
 446 }
 447
 448 /*
 449  * Basically a verbose fseeko() to the actual diff listing.
 450  */
 451 static void
 452 skip_to(off_t file_pos, LINENUM file_line)
 453 {
 454         size_t  len;
 455
 456         if (p_base > file_pos)
 457                 fatal("Internal error: seek %lld>%lld\n",
 458                    (long long)p_base, (long long)file_pos);
 459         if (verbose && p_base < file_pos) {
 460                 fseeko(pfp, p_base, SEEK_SET);
 461                 say("The text leading up to this was:\n--------------------------\n");
 462                 while (ftello(pfp) < file_pos) {
 463                         len = pgets(false);
 464                         if (len == 0)
 465                                 fatal("Unexpected end of file\n");
 466                         say("|%s", buf);
 467                 }
 468                 say("--------------------------\n");
 469         } else
 470                 fseeko(pfp, file_pos, SEEK_SET);
 471         p_input_line = file_line - 1;
 472 }
 473
 474 /* Make this a function for better debugging.  */
 475 static void
 476 malformed(void)
 477 {
 478         fatal("malformed patch at line %ld: %s", p_input_line, buf);
 479         /* about as informative as "Syntax error" in C */
 480 }
 481
 482 /*
 483  * True if the line has been discarded (i.e. it is a line saying
 484  *  "\ No newline at end of file".)
 485  */
 486 static bool
 487 remove_special_line(void)
 488 {
 489         int     c;
 490
 491         c = fgetc(pfp);
 492         if (c == '\\') {
 493                 do {
 494                         c = fgetc(pfp);
 495                 } while (c != EOF && c != '\n');
 496
 497                 return true;
 498         }
 499         if (c != EOF)
 500                 fseeko(pfp, -1, SEEK_CUR);
 501
 502         return false;
 503 }
 504
 505 /*
 506  * True if there is more of the current diff listing to process.
 507  */
 508 bool
 509 another_hunk(void)
 510 {
 511         off_t   line_beginning;                 /* file pos of the current line */
 512         LINENUM repl_beginning;                 /* index of --- line */
 513         LINENUM fillcnt;                        /* #lines of missing ptrn or repl */
 514         LINENUM fillsrc;                        /* index of first line to copy */
 515         LINENUM filldst;                        /* index of first missing line */
 516         bool    ptrn_spaces_eaten;              /* ptrn was slightly malformed */
 517         bool    repl_could_be_missing;          /* no + or ! lines in this hunk */
 518         bool    repl_missing;                   /* we are now backtracking */
 519         off_t   repl_backtrack_position;        /* file pos of first repl line */
 520         LINENUM repl_patch_line;                /* input line number for same */
 521         LINENUM ptrn_copiable;                  /* # of copiable lines in ptrn */
 522         char    *s;
 523         size_t  len;
 524         int     context = 0;
 525
 526         while (p_end >= 0) {
 527                 if (p_end == p_efake)
 528                         p_end = p_bfake;        /* don't free twice */
 529                 else
 530                         free(p_line[p_end]);
 531                 p_end--;
 532         }
 533         p_efake = -1;
 534
 535         p_max = hunkmax;        /* gets reduced when --- found */
 536         if (diff_type == CONTEXT_DIFF || diff_type == NEW_CONTEXT_DIFF) {
 537                 line_beginning = ftello(pfp);
 538                 repl_beginning = 0;
 539                 fillcnt = 0;
 540                 fillsrc = 0;
 541                 filldst = 0;
 542                 ptrn_spaces_eaten = false;
 543                 repl_could_be_missing = true;
 544                 repl_missing = false;
 545                 repl_backtrack_position = 0;
 546                 repl_patch_line = 0;
 547                 ptrn_copiable = 0;
 548
 549                 len = pgets(true);
 550                 p_input_line++;
 551                 if (len == 0 || strnNE(buf, "********", 8)) {
 552                         next_intuit_at(line_beginning, p_input_line);
 553                         return false;
 554                 }
 555                 p_context = 100;
 556                 p_hunk_beg = p_input_line + 1;
 557                 while (p_end < p_max) {
 558                         line_beginning = ftello(pfp);
 559                         len = pgets(true);
 560                         p_input_line++;
 561                         if (len == 0) {
 562                                 if (p_max - p_end < 4) {
 563                                         /* assume blank lines got chopped */
 564                                         strlcpy(buf, "  \n", buf_size);
 565                                 } else {
 566                                         if (repl_beginning && repl_could_be_missing) {
 567                                                 repl_missing = true;
 568                                                 goto hunk_done;
 569                                         }
 570                                         fatal("unexpected end of file in patch\n");
 571                                 }
 572                         }
 573                         p_end++;
 574                         if (p_end >= hunkmax)
 575                                 fatal("Internal error: hunk larger than hunk "
 576                                     "buffer size");
 577                         p_char[p_end] = *buf;
 578                         p_line[p_end] = NULL;
 579                         switch (*buf) {
 580                         case '*':
 581                                 if (strnEQ(buf, "********", 8)) {
 582                                         if (repl_beginning && repl_could_be_missing) {
 583                                                 repl_missing = true;
 584                                                 goto hunk_done;
 585                                         } else
 586                                                 fatal("unexpected end of hunk "
 587                                                     "at line %ld\n",
 588                                                     p_input_line);
 589                                 }
 590                                 if (p_end != 0) {
 591                                         if (repl_beginning && repl_could_be_missing) {
 592                                                 repl_missing = true;
 593                                                 goto hunk_done;
 594                                         }
 595                                         fatal("unexpected *** at line %ld: %s",
 596                                             p_input_line, buf);
 597                                 }
 598                                 context = 0;
 599                                 p_line[p_end] = savestr(buf);
 600                                 if (out_of_mem) {
 601                                         p_end--;
 602                                         return false;
 603                                 }
 604                                 for (s = buf;
 605                                      *s && !isdigit((unsigned char)*s); s++)
 606                                         ;
 607                                 if (!*s)
 608                                         malformed();
 609                                 if (strnEQ(s, "0,0", 3))
 610                                         memmove(s, s + 2, strlen(s + 2) + 1);
 611                                 p_first = strtolinenum(s, &s);
 612                                 if (*s == ',') {
 613                                         for (;
 614                                              *s && !isdigit((unsigned char)*s); s++)
 615                                                 ;
 616                                         if (!*s)
 617                                                 malformed();
 618                                         p_ptrn_lines = strtolinenum(s, &s) - p_first + 1;
 619                                         if (p_ptrn_lines < 0)
 620                                                 malformed();
 621                                 } else if (p_first)
 622                                         p_ptrn_lines = 1;
 623                                 else {
 624                                         p_ptrn_lines = 0;
 625                                         p_first = 1;
 626                                 }
 627                                 if (p_first >= LINENUM_MAX - p_ptrn_lines ||
 628                                     p_ptrn_lines >= LINENUM_MAX - 6)
 629                                         malformed();
 630
 631                                 /* we need this much at least */
 632                                 p_max = p_ptrn_lines + 6;
 633                                 while (p_max >= hunkmax)
 634                                         grow_hunkmax();
 635                                 p_max = hunkmax;
 636                                 break;
 637                         case '-':
 638                                 if (buf[1] == '-') {
 639                                         if (repl_beginning ||
 640                                             (p_end != p_ptrn_lines + 1 +
 641                                             (p_char[p_end - 1] == '\n'))) {
 642                                                 if (p_end == 1) {
 643                                                         /*
 644                                                          * `old' lines were omitted;
 645                                                          * set up to fill them in
 646                                                          * from 'new' context lines.
 647                                                          */
 648                                                         p_end = p_ptrn_lines + 1;
 649                                                         fillsrc = p_end + 1;
 650                                                         filldst = 1;
 651                                                         fillcnt = p_ptrn_lines;
 652                                                 } else {
 653                                                         if (repl_beginning) {
 654                                                                 if (repl_could_be_missing) {
 655                                                                         repl_missing = true;
 656                                                                         goto hunk_done;
 657                                                                 }
 658                                                                 fatal("duplicate \"---\" at line %ld--check line numbers at line %ld\n",
 659                                                                     p_input_line, p_hunk_beg + repl_beginning);
 660                                                         } else {
 661                                                                 fatal("%s \"---\" at line %ld--check line numbers at line %ld\n",
 662                                                                     (p_end <= p_ptrn_lines
 663                                                                     ? "Premature"
 664                                                                     : "Overdue"),
 665                                                                     p_input_line, p_hunk_beg);
 666                                                         }
 667                                                 }
 668                                         }
 669                                         repl_beginning = p_end;
 670                                         repl_backtrack_position = ftello(pfp);
 671                                         repl_patch_line = p_input_line;
 672                                         p_line[p_end] = savestr(buf);
 673                                         if (out_of_mem) {
 674                                                 p_end--;
 675                                                 return false;
 676                                         }
 677                                         p_char[p_end] = '=';
 678                                         for (s = buf; *s && !isdigit((unsigned char)*s); s++)
 679                                                 ;
 680                                         if (!*s)
 681                                                 malformed();
 682                                         p_newfirst = strtolinenum(s, &s);
 683                                         if (*s == ',') {
 684                                                 for (; *s && !isdigit((unsigned char)*s); s++)
 685                                                         ;
 686                                                 if (!*s)
 687                                                         malformed();
 688                                                 p_repl_lines = strtolinenum(s, &s) -
 689                                                     p_newfirst + 1;
 690                                                 if (p_repl_lines < 0)
 691                                                         malformed();
 692                                         } else if (p_newfirst)
 693                                                 p_repl_lines = 1;
 694                                         else {
 695                                                 p_repl_lines = 0;
 696                                                 p_newfirst = 1;
 697                                         }
 698                                         if (p_newfirst >= LINENUM_MAX - p_repl_lines ||
 699                                             p_repl_lines >= LINENUM_MAX - p_end)
 700                                                 malformed();
 701                                         p_max = p_repl_lines + p_end;
 702                                         if (p_max > MAXHUNKSIZE)
 703                                                 fatal("hunk too large (%ld lines) at line %ld: %s",
 704                                                     p_max, p_input_line, buf);
 705                                         while (p_max >= hunkmax)
 706                                                 grow_hunkmax();
 707                                         if (p_repl_lines != ptrn_copiable &&
 708                                             (p_context != 0 || p_repl_lines != 1))
 709                                                 repl_could_be_missing = false;
 710                                         break;
 711                                 }
 712                                 goto change_line;
 713                         case '+':
 714                         case '!':
 715                                 repl_could_be_missing = false;
 716                 change_line:
 717                                 if (buf[1] == '\n' && canonicalize)
 718                                         strlcpy(buf + 1, " \n", buf_size - 1);
 719                                 if (!isspace((unsigned char)buf[1]) &&
 720                                     buf[1] != '>' && buf[1] != '<' &&
 721                                     repl_beginning && repl_could_be_missing) {
 722                                         repl_missing = true;
 723                                         goto hunk_done;
 724                                 }
 725                                 if (context >= 0) {
 726                                         if (context < p_context)
 727                                                 p_context = context;
 728                                         context = -1000;
 729                                 }
 730                                 p_line[p_end] = savestr(buf + 2);
 731                                 if (out_of_mem) {
 732                                         p_end--;
 733                                         return false;
 734                                 }
 735                                 if (p_end == p_ptrn_lines) {
 736                                         if (remove_special_line()) {
 737                                                 int     l;
 738
 739                                                 l = strlen(p_line[p_end]) - 1;
 740                                                 (p_line[p_end])[l] = 0;
 741                                         }
 742                                 }
 743                                 break;
 744                         case '\t':
 745                         case '\n':      /* assume the 2 spaces got eaten */
 746                                 if (repl_beginning && repl_could_be_missing &&
 747                                     (!ptrn_spaces_eaten ||
 748                                     diff_type == NEW_CONTEXT_DIFF)) {
 749                                         repl_missing = true;
 750                                         goto hunk_done;
 751                                 }
 752                                 p_line[p_end] = savestr(buf);
 753                                 if (out_of_mem) {
 754                                         p_end--;
 755                                         return false;
 756                                 }
 757                                 if (p_end != p_ptrn_lines + 1) {
 758                                         ptrn_spaces_eaten |= (repl_beginning != 0);
 759                                         context++;
 760                                         if (!repl_beginning)
 761                                                 ptrn_copiable++;
 762                                         p_char[p_end] = ' ';
 763                                 }
 764                                 break;
 765                         case ' ':
 766                                 if (!isspace((unsigned char)buf[1]) &&
 767                                     repl_beginning && repl_could_be_missing) {
 768                                         repl_missing = true;
 769                                         goto hunk_done;
 770                                 }
 771                                 context++;
 772                                 if (!repl_beginning)
 773                                         ptrn_copiable++;
 774                                 p_line[p_end] = savestr(buf + 2);
 775                                 if (out_of_mem) {
 776                                         p_end--;
 777                                         return false;
 778                                 }
 779                                 break;
 780                         default:
 781                                 if (repl_beginning && repl_could_be_missing) {
 782                                         repl_missing = true;
 783                                         goto hunk_done;
 784                                 }
 785                                 malformed();
 786                         }
 787                         /* set up p_len for strncmp() so we don't have to */
 788                         /* assume null termination */
 789                         if (p_line[p_end])
 790                                 p_len[p_end] = strlen(p_line[p_end]);
 791                         else
 792                                 p_len[p_end] = 0;
 793                 }
 794
 795 hunk_done:
 796                 if (p_end >= 0 && !repl_beginning)
 797                         fatal("no --- found in patch at line %ld\n", pch_hunk_beg());
 798
 799                 if (repl_missing) {
 800
 801                         /* reset state back to just after --- */
 802                         p_input_line = repl_patch_line;
 803                         for (p_end--; p_end > repl_beginning; p_end--)
 804                                 free(p_line[p_end]);
 805                         fseeko(pfp, repl_backtrack_position, SEEK_SET);
 806
 807                         /* redundant 'new' context lines were omitted - set */
 808                         /* up to fill them in from the old file context */
 809                         if (!p_context && p_repl_lines == 1) {
 810                                 p_repl_lines = 0;
 811                                 p_max--;
 812                         }
 813                         fillsrc = 1;
 814                         filldst = repl_beginning + 1;
 815                         fillcnt = p_repl_lines;
 816                         p_end = p_max;
 817                 } else if (!p_context && fillcnt == 1) {
 818                         /* the first hunk was a null hunk with no context */
 819                         /* and we were expecting one line -- fix it up. */
 820                         while (filldst < p_end) {
 821                                 p_line[filldst] = p_line[filldst + 1];
 822                                 p_char[filldst] = p_char[filldst + 1];
 823                                 p_len[filldst] = p_len[filldst + 1];
 824                                 filldst++;
 825                         }
 826 #if 0
 827                         repl_beginning--;       /* this doesn't need to be fixed */
 828 #endif
 829                         p_end--;
 830                         p_first++;      /* do append rather than insert */
 831                         fillcnt = 0;
 832                         p_ptrn_lines = 0;
 833                 }
 834                 if (diff_type == CONTEXT_DIFF &&
 835                     (fillcnt || (p_first > 1 && ptrn_copiable > 2 * p_context))) {
 836                         if (verbose)
 837                                 say("%s\n%s\n%s\n",
 838                                     "(Fascinating--this is really a new-style context diff but without",
 839                                     "the telltale extra asterisks on the *** line that usually indicate",
 840                                     "the new style...)");
 841                         diff_type = NEW_CONTEXT_DIFF;
 842                 }
 843                 /* if there were omitted context lines, fill them in now */
 844                 if (fillcnt) {
 845                         p_bfake = filldst;      /* remember where not to free() */
 846                         p_efake = filldst + fillcnt - 1;
 847                         while (fillcnt-- > 0) {
 848                                 while (fillsrc <= p_end && p_char[fillsrc] != ' ')
 849                                         fillsrc++;
 850                                 if (fillsrc > p_end)
 851                                         fatal("replacement text or line numbers mangled in hunk at line %ld\n",
 852                                             p_hunk_beg);
 853                                 p_line[filldst] = p_line[fillsrc];
 854                                 p_char[filldst] = p_char[fillsrc];
 855                                 p_len[filldst] = p_len[fillsrc];
 856                                 fillsrc++;
 857                                 filldst++;
 858                         }
 859                         while (fillsrc <= p_end && fillsrc != repl_beginning &&
 860                             p_char[fillsrc] != ' ')
 861                                 fillsrc++;
 862 #ifdef DEBUGGING
 863                         if (debug & 64)
 864                                 printf("fillsrc %ld, filldst %ld, rb %ld, e+1 %ld\n",
 865                                 fillsrc, filldst, repl_beginning, p_end + 1);
 866 #endif
 867                         if (fillsrc != p_end + 1 && fillsrc != repl_beginning)
 868                                 malformed();
 869                         if (filldst != p_end + 1 && filldst != repl_beginning)
 870                                 malformed();
 871                 }
 872                 if (p_line[p_end] != NULL) {
 873                         if (remove_special_line()) {
 874                                 p_len[p_end] -= 1;
 875                                 (p_line[p_end])[p_len[p_end]] = 0;
 876                         }
 877                 }
 878         } else if (diff_type == UNI_DIFF) {
 879                 LINENUM fillold;        /* index of old lines */
 880                 LINENUM fillnew;        /* index of new lines */
 881                 char    ch;
 882
 883                 line_beginning = ftello(pfp); /* file pos of the current line */
 884                 len = pgets(true);
 885                 p_input_line++;
 886                 if (len == 0 || strnNE(buf, "@@ -", 4)) {
 887                         next_intuit_at(line_beginning, p_input_line);
 888                         return false;
 889                 }
 890                 s = buf + 4;
 891                 if (!*s)
 892                         malformed();
 893                 p_first = strtolinenum(s, &s);
 894                 if (*s == ',') {
 895                         p_ptrn_lines = strtolinenum(s + 1, &s);
 896                 } else
 897                         p_ptrn_lines = 1;
 898                 if (*s == ' ')
 899                         s++;
 900                 if (*s != '+' || !*++s)
 901                         malformed();
 902                 p_newfirst = strtolinenum(s, &s);
 903                 if (*s == ',') {
 904                         p_repl_lines = strtolinenum(s + 1, &s);
 905                 } else
 906                         p_repl_lines = 1;
 907                 if (*s == ' ')
 908                         s++;
 909                 if (*s != '@')
 910                         malformed();
 911                 if (p_first >= LINENUM_MAX - p_ptrn_lines ||
 912                     p_newfirst > LINENUM_MAX - p_repl_lines ||
 913                     p_ptrn_lines >= LINENUM_MAX - p_repl_lines - 1)
 914                         malformed();
 915                 if (!p_ptrn_lines)
 916                         p_first++;      /* do append rather than insert */
 917                 p_max = p_ptrn_lines + p_repl_lines + 1;
 918                 while (p_max >= hunkmax)
 919                         grow_hunkmax();
 920                 fillold = 1;
 921                 fillnew = fillold + p_ptrn_lines;
 922                 p_end = fillnew + p_repl_lines;
 923                 snprintf(buf, buf_size, "*** %ld,%ld ****\n", p_first,
 924                     p_first + p_ptrn_lines - 1);
 925                 p_line[0] = savestr(buf);
 926                 if (out_of_mem) {
 927                         p_end = -1;
 928                         return false;
 929                 }
 930                 p_char[0] = '*';
 931                 snprintf(buf, buf_size, "--- %ld,%ld ----\n", p_newfirst,
 932                     p_newfirst + p_repl_lines - 1);
 933                 p_line[fillnew] = savestr(buf);
 934                 if (out_of_mem) {
 935                         p_end = 0;
 936                         return false;
 937                 }
 938                 p_char[fillnew++] = '=';
 939                 p_context = 100;
 940                 context = 0;
 941                 p_hunk_beg = p_input_line + 1;
 942                 while (fillold <= p_ptrn_lines || fillnew <= p_end) {
 943                         line_beginning = ftello(pfp);
 944                         len = pgets(true);
 945                         p_input_line++;
 946                         if (len == 0) {
 947                                 if (p_max - fillnew < 3) {
 948                                         /* assume blank lines got chopped */
 949                                         strlcpy(buf, " \n", buf_size);
 950                                 } else {
 951                                         fatal("unexpected end of file in patch\n");
 952                                 }
 953                         }
 954                         if (*buf == '\t' || *buf == '\n') {
 955                                 ch = ' ';       /* assume the space got eaten */
 956                                 s = savestr(buf);
 957                         } else {
 958                                 ch = *buf;
 959                                 s = savestr(buf + 1);
 960                         }
 961                         if (out_of_mem) {
 962                                 while (--fillnew > p_ptrn_lines)
 963                                         free(p_line[fillnew]);
 964                                 p_end = fillold - 1;
 965                                 return false;
 966                         }
 967                         switch (ch) {
 968                         case '-':
 969                                 if (fillold > p_ptrn_lines) {
 970                                         free(s);
 971                                         p_end = fillnew - 1;
 972                                         malformed();
 973                                 }
 974                                 p_char[fillold] = ch;
 975                                 p_line[fillold] = s;
 976                                 p_len[fillold++] = strlen(s);
 977                                 if (fillold > p_ptrn_lines) {
 978                                         if (remove_special_line()) {
 979                                                 p_len[fillold - 1] -= 1;
 980                                                 s[p_len[fillold - 1]] = 0;
 981                                         }
 982                                 }
 983                                 break;
 984                         case '=':
 985                                 ch = ' ';
 986                                 /* FALL THROUGH */
 987                         case ' ':
 988                                 if (fillold > p_ptrn_lines) {
 989                                         free(s);
 990                                         while (--fillnew > p_ptrn_lines)
 991                                                 free(p_line[fillnew]);
 992                                         p_end = fillold - 1;
 993                                         malformed();
 994                                 }
 995                                 context++;
 996                                 p_char[fillold] = ch;
 997                                 p_line[fillold] = s;
 998                                 p_len[fillold++] = strlen(s);
 999                                 s = savestr(s);
1000                                 if (out_of_mem) {
1001                                         while (--fillnew > p_ptrn_lines)
1002                                                 free(p_line[fillnew]);
1003                                         p_end = fillold - 1;
1004                                         return false;
1005                                 }
1006                                 if (fillold > p_ptrn_lines) {
1007                                         if (remove_special_line()) {
1008                                                 p_len[fillold - 1] -= 1;
1009                                                 s[p_len[fillold - 1]] = 0;
1010                                         }
1011                                 }
1012                                 /* FALL THROUGH */
1013                         case '+':
1014                                 if (fillnew > p_end) {
1015                                         free(s);
1016                                         while (--fillnew > p_ptrn_lines)
1017                                                 free(p_line[fillnew]);
1018                                         p_end = fillold - 1;
1019                                         malformed();
1020                                 }
1021                                 p_char[fillnew] = ch;
1022                                 p_line[fillnew] = s;
1023                                 p_len[fillnew++] = strlen(s);
1024                                 if (fillold > p_ptrn_lines) {
1025                                         if (remove_special_line()) {
1026                                                 p_len[fillnew - 1] -= 1;
1027                                                 s[p_len[fillnew - 1]] = 0;
1028                                         }
1029                                 }
1030                                 break;
1031                         default:
1032                                 p_end = fillnew;
1033                                 malformed();
1034                         }
1035                         if (ch != ' ' && context > 0) {
1036                                 if (context < p_context)
1037                                         p_context = context;
1038                                 context = -1000;
1039                         }
1040                 }               /* while */
1041         } else {                /* normal diff--fake it up */
1042                 char    hunk_type;
1043                 int     i;
1044                 LINENUM min, max;
1045
1046                 line_beginning = ftello(pfp);
1047                 p_context = 0;
1048                 len = pgets(true);
1049                 p_input_line++;
1050                 if (len == 0 || !isdigit((unsigned char)*buf)) {
1051                         next_intuit_at(line_beginning, p_input_line);
1052                         return false;
1053                 }
1054                 p_first = strtolinenum(buf, &s);
1055                 if (*s == ',') {
1056                         p_ptrn_lines = strtolinenum(s + 1, &s) - p_first + 1;
1057                         if (p_ptrn_lines < 0)
1058                                 malformed();
1059                 } else
1060                         p_ptrn_lines = (*s != 'a');
1061                 hunk_type = *s;
1062                 if (hunk_type == 'a')
1063                         p_first++;      /* do append rather than insert */
1064                 min = strtolinenum(s + 1, &s);
1065                 if (*s == ',')
1066                         max = strtolinenum(s + 1, &s);
1067                 else
1068                         max = min;
1069                 if (min < 0 || min > max || max - min == LINENUM_MAX)
1070                         malformed();
1071                 if (hunk_type == 'd')
1072                         min++;
1073                 p_newfirst = min;
1074                 p_repl_lines = max - min + 1;
1075                 if (p_newfirst > LINENUM_MAX - p_repl_lines ||
1076                     p_ptrn_lines >= LINENUM_MAX - p_repl_lines - 1)
1077                         malformed();
1078                 p_end = p_ptrn_lines + p_repl_lines + 1;
1079                 if (p_end > MAXHUNKSIZE)
1080                         fatal("hunk too large (%ld lines) at line %ld: %s",
1081                             p_end, p_input_line, buf);
1082                 while (p_end >= hunkmax)
1083                         grow_hunkmax();
1084                 snprintf(buf, buf_size, "*** %ld,%ld\n", p_first,
1085                     p_first + p_ptrn_lines - 1);
1086                 p_line[0] = savestr(buf);
1087                 if (out_of_mem) {
1088                         p_end = -1;
1089                         return false;
1090                 }
1091                 p_char[0] = '*';
1092                 for (i = 1; i <= p_ptrn_lines; i++) {
1093                         len = pgets(true);
1094                         p_input_line++;
1095                         if (len == 0)
1096                                 fatal("unexpected end of file in patch at line %ld\n",
1097                                     p_input_line);
1098                         if (*buf != '<')
1099                                 fatal("< expected at line %ld of patch\n",
1100                                     p_input_line);
1101                         p_line[i] = savestr(buf + 2);
1102                         if (out_of_mem) {
1103                                 p_end = i - 1;
1104                                 return false;
1105                         }
1106                         p_len[i] = strlen(p_line[i]);
1107                         p_char[i] = '-';
1108                 }
1109
1110                 if (remove_special_line()) {
1111                         p_len[i - 1] -= 1;
1112                         (p_line[i - 1])[p_len[i - 1]] = 0;
1113                 }
1114                 if (hunk_type == 'c') {
1115                         len = pgets(true);
1116                         p_input_line++;
1117                         if (len == 0)
1118                                 fatal("unexpected end of file in patch at line %ld\n",
1119                                     p_input_line);
1120                         if (*buf != '-')
1121                                 fatal("--- expected at line %ld of patch\n",
1122                                     p_input_line);
1123                 }
1124                 snprintf(buf, buf_size, "--- %ld,%ld\n", min, max);
1125                 p_line[i] = savestr(buf);
1126                 if (out_of_mem) {
1127                         p_end = i - 1;
1128                         return false;
1129                 }
1130                 p_char[i] = '=';
1131                 for (i++; i <= p_end; i++) {
1132                         len = pgets(true);
1133                         p_input_line++;
1134                         if (len == 0)
1135                                 fatal("unexpected end of file in patch at line %ld\n",
1136                                     p_input_line);
1137                         if (*buf != '>')
1138                                 fatal("> expected at line %ld of patch\n",
1139                                     p_input_line);
1140                         /* Don't overrun if we don't have enough line */
1141                         if (len > 2)
1142                                 p_line[i] = savestr(buf + 2);
1143                         else
1144                                 p_line[i] = savestr("");
1145
1146                         if (out_of_mem) {
1147                                 p_end = i - 1;
1148                                 return false;
1149                         }
1150                         p_len[i] = strlen(p_line[i]);
1151                         p_char[i] = '+';
1152                 }
1153
1154                 if (remove_special_line()) {
1155                         p_len[i - 1] -= 1;
1156                         (p_line[i - 1])[p_len[i - 1]] = 0;
1157                 }
1158         }
1159         if (reverse)            /* backwards patch? */
1160                 if (!pch_swap())
1161                         say("Not enough memory to swap next hunk!\n");
1162 #ifdef DEBUGGING
1163         if (debug & 2) {
1164                 LINENUM i;
1165                 char    special;
1166
1167                 for (i = 0; i <= p_end; i++) {
1168                         if (i == p_ptrn_lines)
1169                                 special = '^';
1170                         else
1171                                 special = ' ';
1172                         fprintf(stderr, "%3ld %c %c %s", i, p_char[i],
1173                             special, p_line[i]);
1174                         fflush(stderr);
1175                 }
1176         }
1177 #endif
1178         if (p_end + 1 < hunkmax)/* paranoia reigns supreme... */
1179                 p_char[p_end + 1] = '^';        /* add a stopper for apply_hunk */
1180         return true;
1181 }
1182
1183 /*
1184  * Input a line from the patch file.
1185  * Worry about indentation if do_indent is true.
1186  * The line is read directly into the buf global variable which
1187  * is resized if necessary in order to hold the complete line.
1188  * Returns the number of characters read including the terminating
1189  * '\n', if any.
1190  */
1191 size_t
1192 pgets(bool do_indent)
1193 {
1194         char *line;
1195         size_t len;
1196         int indent = 0, skipped = 0;
1197
1198         line = fgetln(pfp, &len);
1199         if (line != NULL) {
1200                 if (len + 1 > buf_size) {
1201                         while (len + 1 > buf_size)
1202                                 buf_size *= 2;
1203                         free(buf);
1204                         buf = malloc(buf_size);
1205                         if (buf == NULL)
1206                                 fatal("out of memory\n");
1207                 }
1208                 if (do_indent == 1 && p_indent) {
1209                         for (;
1210                             indent < p_indent && (*line == ' ' || *line == '\t' || *line == 'X');
1211                             line++, skipped++) {
1212                                 if (*line == '\t')
1213                                         indent += 8 - (indent %7);
1214                                 else
1215                                         indent++;
1216                         }
1217                 }
1218                 memcpy(buf, line, len - skipped);
1219                 buf[len - skipped] = '\0';
1220         }
1221         return len;
1222 }
1223
1224
1225 /*
1226  * Reverse the old and new portions of the current hunk.
1227  */
1228 bool
1229 pch_swap(void)
1230 {
1231         char    **tp_line;      /* the text of the hunk */
1232         unsigned short  *tp_len;/* length of each line */
1233         char    *tp_char;       /* +, -, and ! */
1234         LINENUM i;
1235         LINENUM n;
1236         bool    blankline = false;
1237         char    *s;
1238
1239         i = p_first;
1240         p_first = p_newfirst;
1241         p_newfirst = i;
1242
1243         /* make a scratch copy */
1244
1245         tp_line = p_line;
1246         tp_len = p_len;
1247         tp_char = p_char;
1248         p_line = NULL;  /* force set_hunkmax to allocate again */
1249         p_len = NULL;
1250         p_char = NULL;
1251         set_hunkmax();
1252         if (p_line == NULL || p_len == NULL || p_char == NULL) {
1253
1254                 free(p_line);
1255                 p_line = tp_line;
1256                 free(p_len);
1257                 p_len = tp_len;
1258                 free(p_char);
1259                 p_char = tp_char;
1260                 return false;   /* not enough memory to swap hunk! */
1261         }
1262         /* now turn the new into the old */
1263
1264         i = p_ptrn_lines + 1;
1265         if (tp_char[i] == '\n') {       /* account for possible blank line */
1266                 blankline = true;
1267                 i++;
1268         }
1269         if (p_efake >= 0) {     /* fix non-freeable ptr range */
1270                 if (p_efake <= i)
1271                         n = p_end - i + 1;
1272                 else
1273                         n = -i;
1274                 p_efake += n;
1275                 p_bfake += n;
1276         }
1277         for (n = 0; i <= p_end; i++, n++) {
1278                 p_line[n] = tp_line[i];
1279                 p_char[n] = tp_char[i];
1280                 if (p_char[n] == '+')
1281                         p_char[n] = '-';
1282                 p_len[n] = tp_len[i];
1283         }
1284         if (blankline) {
1285                 i = p_ptrn_lines + 1;
1286                 p_line[n] = tp_line[i];
1287                 p_char[n] = tp_char[i];
1288                 p_len[n] = tp_len[i];
1289                 n++;
1290         }
1291         if (p_char[0] != '=')
1292                 fatal("Malformed patch at line %ld: expected '=' found '%c'\n",
1293                     p_input_line, p_char[0]);
1294         p_char[0] = '*';
1295         for (s = p_line[0]; *s; s++)
1296                 if (*s == '-')
1297                         *s = '*';
1298
1299         /* now turn the old into the new */
1300
1301         if (p_char[0] != '*')
1302                 fatal("Malformed patch at line %ld: expected '*' found '%c'\n",
1303                     p_input_line, p_char[0]);
1304         tp_char[0] = '=';
1305         for (s = tp_line[0]; *s; s++)
1306                 if (*s == '*')
1307                         *s = '-';
1308         for (i = 0; n <= p_end; i++, n++) {
1309                 p_line[n] = tp_line[i];
1310                 p_char[n] = tp_char[i];
1311                 if (p_char[n] == '-')
1312                         p_char[n] = '+';
1313                 p_len[n] = tp_len[i];
1314         }
1315
1316         if (i != p_ptrn_lines + 1)
1317                 fatal("Malformed patch at line %ld: expected %ld lines, "
1318                     "got %ld\n",
1319                     p_input_line, p_ptrn_lines + 1, i);
1320
1321         i = p_ptrn_lines;
1322         p_ptrn_lines = p_repl_lines;
1323         p_repl_lines = i;
1324
1325         free(tp_line);
1326         free(tp_len);
1327         free(tp_char);
1328
1329         return true;
1330 }
1331
1332 /*
1333  * Return the specified line position in the old file of the old context.
1334  */
1335 LINENUM
1336 pch_first(void)
1337 {
1338         return p_first;
1339 }
1340
1341 /*
1342  * Return the number of lines of old context.
1343  */
1344 LINENUM
1345 pch_ptrn_lines(void)
1346 {
1347         return p_ptrn_lines;
1348 }
1349
1350 /*
1351  * Return the probable line position in the new file of the first line.
1352  */
1353 LINENUM
1354 pch_newfirst(void)
1355 {
1356         return p_newfirst;
1357 }
1358
1359 /*
1360  * Return the number of lines in the replacement text including context.
1361  */
1362 LINENUM
1363 pch_repl_lines(void)
1364 {
1365         return p_repl_lines;
1366 }
1367
1368 /*
1369  * Return the number of lines in the whole hunk.
1370  */
1371 LINENUM
1372 pch_end(void)
1373 {
1374         return p_end;
1375 }
1376
1377 /*
1378  * Return the number of context lines before the first changed line.
1379  */
1380 LINENUM
1381 pch_context(void)
1382 {
1383         return p_context;
1384 }
1385
1386 /*
1387  * Return the length of a particular patch line.
1388  */
1389 unsigned short
1390 pch_line_len(LINENUM line)
1391 {
1392         return p_len[line];
1393 }
1394
1395 /*
1396  * Return the control character (+, -, *, !, etc) for a patch line.
1397  */
1398 char
1399 pch_char(LINENUM line)
1400 {
1401         return p_char[line];
1402 }
1403
1404 /*
1405  * Return a pointer to a particular patch line.
1406  */
1407 char *
1408 pfetch(LINENUM line)
1409 {
1410         return p_line[line];
1411 }
1412
1413 /*
1414  * Return where in the patch file this hunk began, for error messages.
1415  */
1416 LINENUM
1417 pch_hunk_beg(void)
1418 {
1419         return p_hunk_beg;
1420 }
1421
1422 /*
1423  * Apply an ed script by feeding ed itself.
1424  */
1425 void
1426 do_ed_script(void)
1427 {
1428         char    *t;
1429         off_t   beginning_of_this_line;
1430         FILE    *pipefp = NULL;
1431         int     continuation;
1432
1433         if (!skip_rest_of_patch) {
1434                 if (copy_file(filearg[0], TMPOUTNAME) < 0) {
1435                         unlink(TMPOUTNAME);
1436                         fatal("can't create temp file %s", TMPOUTNAME);
1437                 }
1438                 snprintf(buf, buf_size, "%s%s%s", _PATH_RED,
1439                     verbose ? " " : " -s ", TMPOUTNAME);
1440                 pipefp = popen(buf, "w");
1441         }
1442         for (;;) {
1443                 beginning_of_this_line = ftello(pfp);
1444                 if (pgets(true) == 0) {
1445                         next_intuit_at(beginning_of_this_line, p_input_line);
1446                         break;
1447                 }
1448                 p_input_line++;
1449                 for (t = buf; isdigit((unsigned char)*t) || *t == ','; t++)
1450                         ;
1451                 /* POSIX defines allowed commands as {a,c,d,i,s} */
1452                 if (isdigit((unsigned char)*buf) &&
1453                     (*t == 'a' || *t == 'c' || *t == 'd' || *t == 'i' || *t == 's')) {
1454                         if (pipefp != NULL)
1455                                 fputs(buf, pipefp);
1456                         if (*t == 's') {
1457                                 for (;;) {
1458                                         continuation = 0;
1459                                         t = strchr(buf, '\0') - 1;
1460                                         while (--t >= buf && *t == '\\')
1461                                                 continuation = !continuation;
1462                                         if (!continuation ||
1463                                             pgets(true) == 0)
1464                                                 break;
1465                                         if (pipefp != NULL)
1466                                                 fputs(buf, pipefp);
1467                                 }
1468                         } else if (*t != 'd') {
1469                                 while (pgets(true)) {
1470                                         p_input_line++;
1471                                         if (pipefp != NULL)
1472                                                 fputs(buf, pipefp);
1473                                         if (strEQ(buf, ".\n"))
1474                                                 break;
1475                                 }
1476                         }
1477                 } else {
1478                         next_intuit_at(beginning_of_this_line, p_input_line);
1479                         break;
1480                 }
1481         }
1482         if (pipefp == NULL)
1483                 return;
1484         fprintf(pipefp, "w\n");
1485         fprintf(pipefp, "q\n");
1486         fflush(pipefp);
1487         pclose(pipefp);
1488         ignore_signals();
1489         if (!check_only) {
1490                 if (move_file(TMPOUTNAME, outname) < 0) {
1491                         toutkeep = true;
1492                         chmod(TMPOUTNAME, filemode);
1493                 } else
1494                         chmod(outname, filemode);
1495         }
1496         set_signals(1);
1497 }
1498
1499 /*
1500  * Choose the name of the file to be patched based on POSIX rules.
1501  * NOTE: the POSIX rules are amazingly stupid and we only follow them
1502  *       if the user specified --posix or set POSIXLY_CORRECT.
1503  */
1504 static char *
1505 posix_name(const struct file_name *names, bool assume_exists)
1506 {
1507         char *path = NULL;
1508         int i;
1509
1510         /*
1511          * POSIX states that the filename will be chosen from one
1512          * of the old, new and index names (in that order) if
1513          * the file exists relative to CWD after -p stripping.
1514          */
1515         for (i = 0; i < MAX_FILE; i++) {
1516                 if (names[i].path != NULL && names[i].exists) {
1517                         path = names[i].path;
1518                         break;
1519                 }
1520         }
1521         if (path == NULL && !assume_exists) {
1522                 /*
1523                  * No files found, check to see if the diff could be
1524                  * creating a new file.
1525                  */
1526                 if (path == NULL && ok_to_create_file &&
1527                     names[NEW_FILE].path != NULL)
1528                         path = names[NEW_FILE].path;
1529         }
1530
1531         return path ? xstrdup(path) : NULL;
1532 }
1533
1534 static char *
1535 compare_names(const struct file_name *names, bool assume_exists)
1536 {
1537         size_t min_components, min_baselen, min_len, tmp;
1538         char *best = NULL;
1539         char *path;
1540         int i;
1541
1542         /*
1543          * The "best" name is the one with the fewest number of path
1544          * components, the shortest basename length, and the shortest
1545          * overall length (in that order).  We only use the Index: file
1546          * if neither of the old or new files could be intuited from
1547          * the diff header.
1548          */
1549         min_components = min_baselen = min_len = SIZE_MAX;
1550         for (i = INDEX_FILE; i >= OLD_FILE; i--) {
1551                 path = names[i].path;
1552                 if (path == NULL || (!names[i].exists && !assume_exists))
1553                         continue;
1554                 if ((tmp = num_components(path)) > min_components)
1555                         continue;
1556                 if (tmp < min_components) {
1557                         min_components = tmp;
1558                         best = path;
1559                 }
1560                 if ((tmp = strlen(basename(path))) > min_baselen)
1561                         continue;
1562                 if (tmp < min_baselen) {
1563                         min_baselen = tmp;
1564                         best = path;
1565                 }
1566                 if ((tmp = strlen(path)) > min_len)
1567                         continue;
1568                 min_len = tmp;
1569                 best = path;
1570         }
1571         return best;
1572 }
1573
1574 /*
1575  * Choose the name of the file to be patched based the "best" one
1576  * available.
1577  */
1578 static char *
1579 best_name(const struct file_name *names, bool assume_exists)
1580 {
1581         char *best;
1582
1583         best = compare_names(names, assume_exists);
1584
1585         /* No match?  Check to see if the diff could be creating a new file. */
1586         if (best == NULL && ok_to_create_file)
1587                 best = names[NEW_FILE].path;
1588
1589         return best ? xstrdup(best) : NULL;
1590 }
1591
1592 static size_t
1593 num_components(const char *path)
1594 {
1595         size_t n;
1596         const char *cp;
1597
1598         for (n = 0, cp = path; (cp = strchr(cp, '/')) != NULL; n++, cp++) {
1599                 while (*cp == '/')
1600                         cp++;           /* skip consecutive slashes */
1601         }
1602         return n;
1603 }
1604
1605 /*
1606  * Convert number at NPTR into LINENUM and save address of first
1607  * character that is not a digit in ENDPTR.  If conversion is not
1608  * possible, call fatal.
1609  */
1610 static LINENUM
1611 strtolinenum(char *nptr, char **endptr)
1612 {
1613         LINENUM rv;
1614         char c;
1615         char *p;
1616         const char *errstr;
1617
1618         for (p = nptr; isdigit((unsigned char)*p); p++)
1619                 ;
1620
1621         if (p == nptr)
1622                 malformed();
1623
1624         c = *p;
1625         *p = '\0';
1626
1627         rv = strtonum(nptr, 0, LINENUM_MAX, &errstr);
1628         if (errstr != NULL)
1629                 fatal("invalid line number at line %ld: `%s' is %s\n",
1630                     p_input_line, nptr, errstr);
1631
1632         *p = c;
1633         *endptr = p;
1634
1635         return rv;
1636 }