usr.bin/patch/pch.c

   1
   2 /*-
   3  * Copyright 1986, Larry Wall
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following condition is met:
   7  * 1. Redistributions of source code must retain the above copyright notice,
   8  * this condition and the following disclaimer.
   9  *
  10  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
  11  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  12  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  13  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  14  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  15  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  16  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  17  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  18  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  19  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  20  * SUCH DAMAGE.
  21  *
  22  * patch - a program to apply diffs to original files
  23  *
  24  * -C option added in 1998, original code by Marc Espie, based on FreeBSD
  25  * behaviour
  26  *
  27  * $OpenBSD: pch.c,v 1.39 2012/04/11 08:07:13 ajacoutot Exp $
  28  * $FreeBSD$
  29  */
  30
  31 #include <sys/types.h>
  32 #include <sys/stat.h>
  33
  34 #include <ctype.h>
  35 #include <libgen.h>
  36 #include <limits.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 long     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 LINENUM  p_base;         /* where to intuit this time */
  64 static LINENUM  p_bline;        /* line # of p_base */
  65 static LINENUM  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(LINENUM, LINENUM);
  76 static void     skip_to(LINENUM, 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
  82 /*
  83  * Prepare to look for the next patch in the patch file.
  84  */
  85 void
  86 re_patch(void)
  87 {
  88         p_first = 0;
  89         p_newfirst = 0;
  90         p_ptrn_lines = 0;
  91         p_repl_lines = 0;
  92         p_end = (LINENUM) - 1;
  93         p_max = 0;
  94         p_indent = 0;
  95 }
  96
  97 /*
  98  * Open the patch file at the beginning of time.
  99  */
 100 void
 101 open_patch_file(const char *filename)
 102 {
 103         struct stat filestat;
 104         int nr, nw;
 105
 106         if (filename == NULL || *filename == '\0' || strEQ(filename, "-")) {
 107                 pfp = fopen(TMPPATNAME, "w");
 108                 if (pfp == NULL)
 109                         pfatal("can't create %s", TMPPATNAME);
 110                 while ((nr = fread(buf, 1, buf_size, stdin)) > 0) {
 111                         nw = fwrite(buf, 1, nr, pfp);
 112                         if (nr != nw)
 113                                 pfatal("write error to %s", TMPPATNAME);
 114                 }
 115                 if (ferror(pfp) || fclose(pfp))
 116                         pfatal("can't write %s", TMPPATNAME);
 117                 filename = TMPPATNAME;
 118         }
 119         pfp = fopen(filename, "r");
 120         if (pfp == NULL)
 121                 pfatal("patch file %s not found", filename);
 122         fstat(fileno(pfp), &filestat);
 123         p_filesize = filestat.st_size;
 124         next_intuit_at(0L, 1L); /* start at the beginning */
 125         set_hunkmax();
 126 }
 127
 128 /*
 129  * Make sure our dynamically realloced tables are malloced to begin with.
 130  */
 131 void
 132 set_hunkmax(void)
 133 {
 134         if (p_line == NULL)
 135                 p_line = malloc(hunkmax * sizeof(char *));
 136         if (p_len == NULL)
 137                 p_len = malloc(hunkmax * sizeof(unsigned short));
 138         if (p_char == NULL)
 139                 p_char = malloc(hunkmax * sizeof(char));
 140 }
 141
 142 /*
 143  * Enlarge the arrays containing the current hunk of patch.
 144  */
 145 static void
 146 grow_hunkmax(void)
 147 {
 148         int new_hunkmax = hunkmax * 2;
 149
 150         if (p_line == NULL || p_len == NULL || p_char == NULL)
 151                 fatal("Internal memory allocation error\n");
 152
 153         p_line = reallocf(p_line, new_hunkmax * sizeof(char *));
 154         p_len = reallocf(p_len, new_hunkmax * sizeof(unsigned short));
 155         p_char = reallocf(p_char, new_hunkmax * sizeof(char));
 156
 157         if (p_line != NULL && p_len != NULL && p_char != NULL) {
 158                 hunkmax = new_hunkmax;
 159                 return;
 160         }
 161
 162         if (!using_plan_a)
 163                 fatal("out of memory\n");
 164         out_of_mem = true;      /* whatever is null will be allocated again */
 165                                 /* from within plan_a(), of all places */
 166 }
 167
 168 /* True if the remainder of the patch file contains a diff of some sort. */
 169
 170 bool
 171 there_is_another_patch(void)
 172 {
 173         bool exists = false;
 174
 175         if (p_base != 0L && p_base >= p_filesize) {
 176                 if (verbose)
 177                         say("done\n");
 178                 return false;
 179         }
 180         if (verbose)
 181                 say("Hmm...");
 182         diff_type = intuit_diff_type();
 183         if (!diff_type) {
 184                 if (p_base != 0L) {
 185                         if (verbose)
 186                                 say("  Ignoring the trailing garbage.\ndone\n");
 187                 } else
 188                         say("  I can't seem to find a patch in there anywhere.\n");
 189                 return false;
 190         }
 191         if (verbose)
 192                 say("  %sooks like %s to me...\n",
 193                     (p_base == 0L ? "L" : "The next patch l"),
 194                     diff_type == UNI_DIFF ? "a unified diff" :
 195                     diff_type == CONTEXT_DIFF ? "a context diff" :
 196                 diff_type == NEW_CONTEXT_DIFF ? "a new-style context diff" :
 197                     diff_type == NORMAL_DIFF ? "a normal diff" :
 198                     "an ed script");
 199         if (p_indent && verbose)
 200                 say("(Patch is indented %d space%s.)\n", p_indent,
 201                     p_indent == 1 ? "" : "s");
 202         skip_to(p_start, p_sline);
 203         while (filearg[0] == NULL) {
 204                 if (force || batch) {
 205                         say("No file to patch.  Skipping...\n");
 206                         filearg[0] = savestr(bestguess);
 207                         skip_rest_of_patch = true;
 208                         return true;
 209                 }
 210                 ask("File to patch: ");
 211                 if (*buf != '\n') {
 212                         free(bestguess);
 213                         bestguess = savestr(buf);
 214                         filearg[0] = fetchname(buf, &exists, 0);
 215                 }
 216                 if (!exists) {
 217                         ask("No file found--skip this patch? [n] ");
 218                         if (*buf != 'y')
 219                                 continue;
 220                         if (verbose)
 221                                 say("Skipping patch...\n");
 222                         free(filearg[0]);
 223                         filearg[0] = fetchname(bestguess, &exists, 0);
 224                         skip_rest_of_patch = true;
 225                         return true;
 226                 }
 227         }
 228         return true;
 229 }
 230
 231 static void
 232 p4_fetchname(struct file_name *name, char *str)
 233 {
 234         char *t, *h;
 235
 236         /* Skip leading whitespace. */
 237         while (isspace((unsigned char)*str))
 238                 str++;
 239
 240         /* Remove the file revision number. */
 241         for (t = str, h = NULL; *t != '\0' && !isspace((unsigned char)*t); t++)
 242                 if (*t == '#')
 243                         h = t;
 244         if (h != NULL)
 245                 *h = '\0';
 246
 247         name->path = fetchname(str, &name->exists, strippath);
 248 }
 249
 250 /* Determine what kind of diff is in the remaining part of the patch file. */
 251
 252 static int
 253 intuit_diff_type(void)
 254 {
 255         long    this_line = 0, previous_line;
 256         long    first_command_line = -1;
 257         LINENUM fcl_line = -1;
 258         bool    last_line_was_command = false, this_is_a_command = false;
 259         bool    stars_last_line = false, stars_this_line = false;
 260         char    *s, *t;
 261         int     indent, retval;
 262         struct file_name names[MAX_FILE];
 263
 264         memset(names, 0, sizeof(names));
 265         ok_to_create_file = false;
 266         fseek(pfp, p_base, SEEK_SET);
 267         p_input_line = p_bline - 1;
 268         for (;;) {
 269                 previous_line = this_line;
 270                 last_line_was_command = this_is_a_command;
 271                 stars_last_line = stars_this_line;
 272                 this_line = ftell(pfp);
 273                 indent = 0;
 274                 p_input_line++;
 275                 if (pgets(false) == 0) {
 276                         if (first_command_line >= 0L) {
 277                                 /* nothing but deletes!? */
 278                                 p_start = first_command_line;
 279                                 p_sline = fcl_line;
 280                                 retval = ED_DIFF;
 281                                 goto scan_exit;
 282                         } else {
 283                                 p_start = this_line;
 284                                 p_sline = p_input_line;
 285                                 retval = 0;
 286                                 goto scan_exit;
 287                         }
 288                 }
 289                 for (s = buf; *s == ' ' || *s == '\t' || *s == 'X'; s++) {
 290                         if (*s == '\t')
 291                                 indent += 8 - (indent % 8);
 292                         else
 293                                 indent++;
 294                 }
 295                 for (t = s; isdigit((unsigned char)*t) || *t == ','; t++)
 296                         ;
 297                 this_is_a_command = (isdigit((unsigned char)*s) &&
 298                     (*t == 'd' || *t == 'c' || *t == 'a'));
 299                 if (first_command_line < 0L && this_is_a_command) {
 300                         first_command_line = this_line;
 301                         fcl_line = p_input_line;
 302                         p_indent = indent;      /* assume this for now */
 303                 }
 304                 if (!stars_last_line && strnEQ(s, "*** ", 4))
 305                         names[OLD_FILE].path = fetchname(s + 4,
 306                             &names[OLD_FILE].exists, strippath);
 307                 else if (strnEQ(s, "--- ", 4))
 308                         names[NEW_FILE].path = fetchname(s + 4,
 309                             &names[NEW_FILE].exists, strippath);
 310                 else if (strnEQ(s, "+++ ", 4))
 311                         /* pretend it is the old name */
 312                         names[OLD_FILE].path = fetchname(s + 4,
 313                             &names[OLD_FILE].exists, strippath);
 314                 else if (strnEQ(s, "Index:", 6))
 315                         names[INDEX_FILE].path = fetchname(s + 6,
 316                             &names[INDEX_FILE].exists, strippath);
 317                 else if (strnEQ(s, "Prereq:", 7)) {
 318                         for (t = s + 7; isspace((unsigned char)*t); t++)
 319                                 ;
 320                         revision = savestr(t);
 321                         for (t = revision; *t && !isspace((unsigned char)*t); t++)
 322                                 ;
 323                         *t = '\0';
 324                         if (*revision == '\0') {
 325                                 free(revision);
 326                                 revision = NULL;
 327                         }
 328                 } else if (strnEQ(s, "==== ", 5)) {
 329                         /* Perforce-style diffs. */
 330                         if ((t = strstr(s + 5, " - ")) != NULL)
 331                                 p4_fetchname(&names[NEW_FILE], t + 3);
 332                         p4_fetchname(&names[OLD_FILE], s + 5);
 333                 }
 334                 if ((!diff_type || diff_type == ED_DIFF) &&
 335                     first_command_line >= 0L &&
 336                     strEQ(s, ".\n")) {
 337                         p_indent = indent;
 338                         p_start = first_command_line;
 339                         p_sline = fcl_line;
 340                         retval = ED_DIFF;
 341                         goto scan_exit;
 342                 }
 343                 if ((!diff_type || diff_type == UNI_DIFF) && strnEQ(s, "@@ -", 4)) {
 344                         if (strnEQ(s + 4, "0,0", 3))
 345                                 ok_to_create_file = true;
 346                         p_indent = indent;
 347                         p_start = this_line;
 348                         p_sline = p_input_line;
 349                         retval = UNI_DIFF;
 350                         goto scan_exit;
 351                 }
 352                 stars_this_line = strnEQ(s, "********", 8);
 353                 if ((!diff_type || diff_type == CONTEXT_DIFF) && stars_last_line &&
 354                     strnEQ(s, "*** ", 4)) {
 355                         if (atol(s + 4) == 0)
 356                                 ok_to_create_file = true;
 357                         /*
 358                          * If this is a new context diff the character just
 359                          * before the newline is a '*'.
 360                          */
 361                         while (*s != '\n')
 362                                 s++;
 363                         p_indent = indent;
 364                         p_start = previous_line;
 365                         p_sline = p_input_line - 1;
 366                         retval = (*(s - 1) == '*' ? NEW_CONTEXT_DIFF : CONTEXT_DIFF);
 367                         goto scan_exit;
 368                 }
 369                 if ((!diff_type || diff_type == NORMAL_DIFF) &&
 370                     last_line_was_command &&
 371                     (strnEQ(s, "< ", 2) || strnEQ(s, "> ", 2))) {
 372                         p_start = previous_line;
 373                         p_sline = p_input_line - 1;
 374                         p_indent = indent;
 375                         retval = NORMAL_DIFF;
 376                         goto scan_exit;
 377                 }
 378         }
 379 scan_exit:
 380         if (retval == UNI_DIFF) {
 381                 /* unswap old and new */
 382                 struct file_name tmp = names[OLD_FILE];
 383                 names[OLD_FILE] = names[NEW_FILE];
 384                 names[NEW_FILE] = tmp;
 385         }
 386         if (filearg[0] == NULL) {
 387                 if (posix)
 388                         filearg[0] = posix_name(names, ok_to_create_file);
 389                 else {
 390                         /* Ignore the Index: name for context diffs, like GNU */
 391                         if (names[OLD_FILE].path != NULL ||
 392                             names[NEW_FILE].path != NULL) {
 393                                 free(names[INDEX_FILE].path);
 394                                 names[INDEX_FILE].path = NULL;
 395                         }
 396                         filearg[0] = best_name(names, ok_to_create_file);
 397                 }
 398         }
 399
 400         free(bestguess);
 401         bestguess = NULL;
 402         if (filearg[0] != NULL)
 403                 bestguess = savestr(filearg[0]);
 404         else if (!ok_to_create_file) {
 405                 /*
 406                  * We don't want to create a new file but we need a
 407                  * filename to set bestguess.  Avoid setting filearg[0]
 408                  * so the file is not created automatically.
 409                  */
 410                 if (posix)
 411                         bestguess = posix_name(names, true);
 412                 else
 413                         bestguess = best_name(names, true);
 414         }
 415         free(names[OLD_FILE].path);
 416         free(names[NEW_FILE].path);
 417         free(names[INDEX_FILE].path);
 418         return retval;
 419 }
 420
 421 /*
 422  * Remember where this patch ends so we know where to start up again.
 423  */
 424 static void
 425 next_intuit_at(LINENUM file_pos, LINENUM file_line)
 426 {
 427         p_base = file_pos;
 428         p_bline = file_line;
 429 }
 430
 431 /*
 432  * Basically a verbose fseek() to the actual diff listing.
 433  */
 434 static void
 435 skip_to(LINENUM file_pos, LINENUM file_line)
 436 {
 437         size_t  len;
 438
 439         if (p_base > file_pos)
 440                 fatal("Internal error: seek %ld>%ld\n", p_base, file_pos);
 441         if (verbose && p_base < file_pos) {
 442                 fseek(pfp, p_base, SEEK_SET);
 443                 say("The text leading up to this was:\n--------------------------\n");
 444                 while (ftell(pfp) < file_pos) {
 445                         len = pgets(false);
 446                         if (len == 0)
 447                                 fatal("Unexpected end of file\n");
 448                         say("|%s", buf);
 449                 }
 450                 say("--------------------------\n");
 451         } else
 452                 fseek(pfp, file_pos, SEEK_SET);
 453         p_input_line = file_line - 1;
 454 }
 455
 456 /* Make this a function for better debugging.  */
 457 static void
 458 malformed(void)
 459 {
 460         fatal("malformed patch at line %ld: %s", p_input_line, buf);
 461         /* about as informative as "Syntax error" in C */
 462 }
 463
 464 /*
 465  * True if the line has been discarded (i.e. it is a line saying
 466  *  "\ No newline at end of file".)
 467  */
 468 static bool
 469 remove_special_line(void)
 470 {
 471         int     c;
 472
 473         c = fgetc(pfp);
 474         if (c == '\\') {
 475                 do {
 476                         c = fgetc(pfp);
 477                 } while (c != EOF && c != '\n');
 478
 479                 return true;
 480         }
 481         if (c != EOF)
 482                 fseek(pfp, -1L, SEEK_CUR);
 483
 484         return false;
 485 }
 486
 487 /*
 488  * True if there is more of the current diff listing to process.
 489  */
 490 bool
 491 another_hunk(void)
 492 {
 493         long    line_beginning;                 /* file pos of the current line */
 494         LINENUM repl_beginning;                 /* index of --- line */
 495         LINENUM fillcnt;                        /* #lines of missing ptrn or repl */
 496         LINENUM fillsrc;                        /* index of first line to copy */
 497         LINENUM filldst;                        /* index of first missing line */
 498         bool    ptrn_spaces_eaten;              /* ptrn was slightly misformed */
 499         bool    repl_could_be_missing;          /* no + or ! lines in this hunk */
 500         bool    repl_missing;                   /* we are now backtracking */
 501         long    repl_backtrack_position;        /* file pos of first repl line */
 502         LINENUM repl_patch_line;                /* input line number for same */
 503         LINENUM ptrn_copiable;                  /* # of copiable lines in ptrn */
 504         char    *s;
 505         size_t  len;
 506         int     context = 0;
 507
 508         while (p_end >= 0) {
 509                 if (p_end == p_efake)
 510                         p_end = p_bfake;        /* don't free twice */
 511                 else
 512                         free(p_line[p_end]);
 513                 p_end--;
 514         }
 515         p_efake = -1;
 516
 517         p_max = hunkmax;        /* gets reduced when --- found */
 518         if (diff_type == CONTEXT_DIFF || diff_type == NEW_CONTEXT_DIFF) {
 519                 line_beginning = ftell(pfp);
 520                 repl_beginning = 0;
 521                 fillcnt = 0;
 522                 fillsrc = 0;
 523                 filldst = 0;
 524                 ptrn_spaces_eaten = false;
 525                 repl_could_be_missing = true;
 526                 repl_missing = false;
 527                 repl_backtrack_position = 0;
 528                 repl_patch_line = 0;
 529                 ptrn_copiable = 0;
 530
 531                 len = pgets(true);
 532                 p_input_line++;
 533                 if (len == 0 || strnNE(buf, "********", 8)) {
 534                         next_intuit_at(line_beginning, p_input_line);
 535                         return false;
 536                 }
 537                 p_context = 100;
 538                 p_hunk_beg = p_input_line + 1;
 539                 while (p_end < p_max) {
 540                         line_beginning = ftell(pfp);
 541                         len = pgets(true);
 542                         p_input_line++;
 543                         if (len == 0) {
 544                                 if (p_max - p_end < 4) {
 545                                         /* assume blank lines got chopped */
 546                                         strlcpy(buf, "  \n", buf_size);
 547                                 } else {
 548                                         if (repl_beginning && repl_could_be_missing) {
 549                                                 repl_missing = true;
 550                                                 goto hunk_done;
 551                                         }
 552                                         fatal("unexpected end of file in patch\n");
 553                                 }
 554                         }
 555                         p_end++;
 556                         if (p_end >= hunkmax)
 557                                 fatal("Internal error: hunk larger than hunk "
 558                                     "buffer size");
 559                         p_char[p_end] = *buf;
 560                         p_line[p_end] = NULL;
 561                         switch (*buf) {
 562                         case '*':
 563                                 if (strnEQ(buf, "********", 8)) {
 564                                         if (repl_beginning && repl_could_be_missing) {
 565                                                 repl_missing = true;
 566                                                 goto hunk_done;
 567                                         } else
 568                                                 fatal("unexpected end of hunk "
 569                                                     "at line %ld\n",
 570                                                     p_input_line);
 571                                 }
 572                                 if (p_end != 0) {
 573                                         if (repl_beginning && repl_could_be_missing) {
 574                                                 repl_missing = true;
 575                                                 goto hunk_done;
 576                                         }
 577                                         fatal("unexpected *** at line %ld: %s",
 578                                             p_input_line, buf);
 579                                 }
 580                                 context = 0;
 581                                 p_line[p_end] = savestr(buf);
 582                                 if (out_of_mem) {
 583                                         p_end--;
 584                                         return false;
 585                                 }
 586                                 for (s = buf; *s && !isdigit((unsigned char)*s); s++)
 587                                         ;
 588                                 if (!*s)
 589                                         malformed();
 590                                 if (strnEQ(s, "0,0", 3))
 591                                         memmove(s, s + 2, strlen(s + 2) + 1);
 592                                 p_first = (LINENUM) atol(s);
 593                                 while (isdigit((unsigned char)*s))
 594                                         s++;
 595                                 if (*s == ',') {
 596                                         for (; *s && !isdigit((unsigned char)*s); s++)
 597                                                 ;
 598                                         if (!*s)
 599                                                 malformed();
 600                                         p_ptrn_lines = ((LINENUM) atol(s)) - p_first + 1;
 601                                 } else if (p_first)
 602                                         p_ptrn_lines = 1;
 603                                 else {
 604                                         p_ptrn_lines = 0;
 605                                         p_first = 1;
 606                                 }
 607
 608                                 /* we need this much at least */
 609                                 p_max = p_ptrn_lines + 6;
 610                                 while (p_max >= hunkmax)
 611                                         grow_hunkmax();
 612                                 p_max = hunkmax;
 613                                 break;
 614                         case '-':
 615                                 if (buf[1] == '-') {
 616                                         if (repl_beginning ||
 617                                             (p_end != p_ptrn_lines + 1 +
 618                                             (p_char[p_end - 1] == '\n'))) {
 619                                                 if (p_end == 1) {
 620                                                         /*
 621                                                          * `old' lines were omitted;
 622                                                          * set up to fill them in
 623                                                          * from 'new' context lines.
 624                                                          */
 625                                                         p_end = p_ptrn_lines + 1;
 626                                                         fillsrc = p_end + 1;
 627                                                         filldst = 1;
 628                                                         fillcnt = p_ptrn_lines;
 629                                                 } else {
 630                                                         if (repl_beginning) {
 631                                                                 if (repl_could_be_missing) {
 632                                                                         repl_missing = true;
 633                                                                         goto hunk_done;
 634                                                                 }
 635                                                                 fatal("duplicate \"---\" at line %ld--check line numbers at line %ld\n",
 636                                                                     p_input_line, p_hunk_beg + repl_beginning);
 637                                                         } else {
 638                                                                 fatal("%s \"---\" at line %ld--check line numbers at line %ld\n",
 639                                                                     (p_end <= p_ptrn_lines
 640                                                                     ? "Premature"
 641                                                                     : "Overdue"),
 642                                                                     p_input_line, p_hunk_beg);
 643                                                         }
 644                                                 }
 645                                         }
 646                                         repl_beginning = p_end;
 647                                         repl_backtrack_position = ftell(pfp);
 648                                         repl_patch_line = p_input_line;
 649                                         p_line[p_end] = savestr(buf);
 650                                         if (out_of_mem) {
 651                                                 p_end--;
 652                                                 return false;
 653                                         }
 654                                         p_char[p_end] = '=';
 655                                         for (s = buf; *s && !isdigit((unsigned char)*s); s++)
 656                                                 ;
 657                                         if (!*s)
 658                                                 malformed();
 659                                         p_newfirst = (LINENUM) atol(s);
 660                                         while (isdigit((unsigned char)*s))
 661                                                 s++;
 662                                         if (*s == ',') {
 663                                                 for (; *s && !isdigit((unsigned char)*s); s++)
 664                                                         ;
 665                                                 if (!*s)
 666                                                         malformed();
 667                                                 p_repl_lines = ((LINENUM) atol(s)) -
 668                                                     p_newfirst + 1;
 669                                         } else if (p_newfirst)
 670                                                 p_repl_lines = 1;
 671                                         else {
 672                                                 p_repl_lines = 0;
 673                                                 p_newfirst = 1;
 674                                         }
 675                                         p_max = p_repl_lines + p_end;
 676                                         if (p_max > MAXHUNKSIZE)
 677                                                 fatal("hunk too large (%ld lines) at line %ld: %s",
 678                                                     p_max, p_input_line, buf);
 679                                         while (p_max >= hunkmax)
 680                                                 grow_hunkmax();
 681                                         if (p_repl_lines != ptrn_copiable &&
 682                                             (p_context != 0 || p_repl_lines != 1))
 683                                                 repl_could_be_missing = false;
 684                                         break;
 685                                 }
 686                                 goto change_line;
 687                         case '+':
 688                         case '!':
 689                                 repl_could_be_missing = false;
 690                 change_line:
 691                                 if (buf[1] == '\n' && canonicalize)
 692                                         strlcpy(buf + 1, " \n", buf_size - 1);
 693                                 if (!isspace((unsigned char)buf[1]) && buf[1] != '>' &&
 694                                     buf[1] != '<' &&
 695                                     repl_beginning && repl_could_be_missing) {
 696                                         repl_missing = true;
 697                                         goto hunk_done;
 698                                 }
 699                                 if (context >= 0) {
 700                                         if (context < p_context)
 701                                                 p_context = context;
 702                                         context = -1000;
 703                                 }
 704                                 p_line[p_end] = savestr(buf + 2);
 705                                 if (out_of_mem) {
 706                                         p_end--;
 707                                         return false;
 708                                 }
 709                                 if (p_end == p_ptrn_lines) {
 710                                         if (remove_special_line()) {
 711                                                 int     l;
 712
 713                                                 l = strlen(p_line[p_end]) - 1;
 714                                                 (p_line[p_end])[l] = 0;
 715                                         }
 716                                 }
 717                                 break;
 718                         case '\t':
 719                         case '\n':      /* assume the 2 spaces got eaten */
 720                                 if (repl_beginning && repl_could_be_missing &&
 721                                     (!ptrn_spaces_eaten ||
 722                                     diff_type == NEW_CONTEXT_DIFF)) {
 723                                         repl_missing = true;
 724                                         goto hunk_done;
 725                                 }
 726                                 p_line[p_end] = savestr(buf);
 727                                 if (out_of_mem) {
 728                                         p_end--;
 729                                         return false;
 730                                 }
 731                                 if (p_end != p_ptrn_lines + 1) {
 732                                         ptrn_spaces_eaten |= (repl_beginning != 0);
 733                                         context++;
 734                                         if (!repl_beginning)
 735                                                 ptrn_copiable++;
 736                                         p_char[p_end] = ' ';
 737                                 }
 738                                 break;
 739                         case ' ':
 740                                 if (!isspace((unsigned char)buf[1]) &&
 741                                     repl_beginning && repl_could_be_missing) {
 742                                         repl_missing = true;
 743                                         goto hunk_done;
 744                                 }
 745                                 context++;
 746                                 if (!repl_beginning)
 747                                         ptrn_copiable++;
 748                                 p_line[p_end] = savestr(buf + 2);
 749                                 if (out_of_mem) {
 750                                         p_end--;
 751                                         return false;
 752                                 }
 753                                 break;
 754                         default:
 755                                 if (repl_beginning && repl_could_be_missing) {
 756                                         repl_missing = true;
 757                                         goto hunk_done;
 758                                 }
 759                                 malformed();
 760                         }
 761                         /* set up p_len for strncmp() so we don't have to */
 762                         /* assume null termination */
 763                         if (p_line[p_end])
 764                                 p_len[p_end] = strlen(p_line[p_end]);
 765                         else
 766                                 p_len[p_end] = 0;
 767                 }
 768
 769 hunk_done:
 770                 if (p_end >= 0 && !repl_beginning)
 771                         fatal("no --- found in patch at line %ld\n", pch_hunk_beg());
 772
 773                 if (repl_missing) {
 774
 775                         /* reset state back to just after --- */
 776                         p_input_line = repl_patch_line;
 777                         for (p_end--; p_end > repl_beginning; p_end--)
 778                                 free(p_line[p_end]);
 779                         fseek(pfp, repl_backtrack_position, SEEK_SET);
 780
 781                         /* redundant 'new' context lines were omitted - set */
 782                         /* up to fill them in from the old file context */
 783                         if (!p_context && p_repl_lines == 1) {
 784                                 p_repl_lines = 0;
 785                                 p_max--;
 786                         }
 787                         fillsrc = 1;
 788                         filldst = repl_beginning + 1;
 789                         fillcnt = p_repl_lines;
 790                         p_end = p_max;
 791                 } else if (!p_context && fillcnt == 1) {
 792                         /* the first hunk was a null hunk with no context */
 793                         /* and we were expecting one line -- fix it up. */
 794                         while (filldst < p_end) {
 795                                 p_line[filldst] = p_line[filldst + 1];
 796                                 p_char[filldst] = p_char[filldst + 1];
 797                                 p_len[filldst] = p_len[filldst + 1];
 798                                 filldst++;
 799                         }
 800 #if 0
 801                         repl_beginning--;       /* this doesn't need to be fixed */
 802 #endif
 803                         p_end--;
 804                         p_first++;      /* do append rather than insert */
 805                         fillcnt = 0;
 806                         p_ptrn_lines = 0;
 807                 }
 808                 if (diff_type == CONTEXT_DIFF &&
 809                     (fillcnt || (p_first > 1 && ptrn_copiable > 2 * p_context))) {
 810                         if (verbose)
 811                                 say("%s\n%s\n%s\n",
 812                                     "(Fascinating--this is really a new-style context diff but without",
 813                                     "the telltale extra asterisks on the *** line that usually indicate",
 814                                     "the new style...)");
 815                         diff_type = NEW_CONTEXT_DIFF;
 816                 }
 817                 /* if there were omitted context lines, fill them in now */
 818                 if (fillcnt) {
 819                         p_bfake = filldst;      /* remember where not to free() */
 820                         p_efake = filldst + fillcnt - 1;
 821                         while (fillcnt-- > 0) {
 822                                 while (fillsrc <= p_end && p_char[fillsrc] != ' ')
 823                                         fillsrc++;
 824                                 if (fillsrc > p_end)
 825                                         fatal("replacement text or line numbers mangled in hunk at line %ld\n",
 826                                             p_hunk_beg);
 827                                 p_line[filldst] = p_line[fillsrc];
 828                                 p_char[filldst] = p_char[fillsrc];
 829                                 p_len[filldst] = p_len[fillsrc];
 830                                 fillsrc++;
 831                                 filldst++;
 832                         }
 833                         while (fillsrc <= p_end && fillsrc != repl_beginning &&
 834                             p_char[fillsrc] != ' ')
 835                                 fillsrc++;
 836 #ifdef DEBUGGING
 837                         if (debug & 64)
 838                                 printf("fillsrc %ld, filldst %ld, rb %ld, e+1 %ld\n",
 839                                 fillsrc, filldst, repl_beginning, p_end + 1);
 840 #endif
 841                         if (fillsrc != p_end + 1 && fillsrc != repl_beginning)
 842                                 malformed();
 843                         if (filldst != p_end + 1 && filldst != repl_beginning)
 844                                 malformed();
 845                 }
 846                 if (p_line[p_end] != NULL) {
 847                         if (remove_special_line()) {
 848                                 p_len[p_end] -= 1;
 849                                 (p_line[p_end])[p_len[p_end]] = 0;
 850                         }
 851                 }
 852         } else if (diff_type == UNI_DIFF) {
 853                 LINENUM fillold;        /* index of old lines */
 854                 LINENUM fillnew;        /* index of new lines */
 855                 char    ch;
 856
 857                 line_beginning = ftell(pfp); /* file pos of the current line */
 858                 len = pgets(true);
 859                 p_input_line++;
 860                 if (len == 0 || strnNE(buf, "@@ -", 4)) {
 861                         next_intuit_at(line_beginning, p_input_line);
 862                         return false;
 863                 }
 864                 s = buf + 4;
 865                 if (!*s)
 866                         malformed();
 867                 p_first = (LINENUM) atol(s);
 868                 while (isdigit((unsigned char)*s))
 869                         s++;
 870                 if (*s == ',') {
 871                         p_ptrn_lines = (LINENUM) atol(++s);
 872                         while (isdigit((unsigned char)*s))
 873                                 s++;
 874                 } else
 875                         p_ptrn_lines = 1;
 876                 if (*s == ' ')
 877                         s++;
 878                 if (*s != '+' || !*++s)
 879                         malformed();
 880                 p_newfirst = (LINENUM) atol(s);
 881                 while (isdigit((unsigned char)*s))
 882                         s++;
 883                 if (*s == ',') {
 884                         p_repl_lines = (LINENUM) atol(++s);
 885                         while (isdigit((unsigned char)*s))
 886                                 s++;
 887                 } else
 888                         p_repl_lines = 1;
 889                 if (*s == ' ')
 890                         s++;
 891                 if (*s != '@')
 892                         malformed();
 893                 if (!p_ptrn_lines)
 894                         p_first++;      /* do append rather than insert */
 895                 p_max = p_ptrn_lines + p_repl_lines + 1;
 896                 while (p_max >= hunkmax)
 897                         grow_hunkmax();
 898                 fillold = 1;
 899                 fillnew = fillold + p_ptrn_lines;
 900                 p_end = fillnew + p_repl_lines;
 901                 snprintf(buf, buf_size, "*** %ld,%ld ****\n", p_first,
 902                     p_first + p_ptrn_lines - 1);
 903                 p_line[0] = savestr(buf);
 904                 if (out_of_mem) {
 905                         p_end = -1;
 906                         return false;
 907                 }
 908                 p_char[0] = '*';
 909                 snprintf(buf, buf_size, "--- %ld,%ld ----\n", p_newfirst,
 910                     p_newfirst + p_repl_lines - 1);
 911                 p_line[fillnew] = savestr(buf);
 912                 if (out_of_mem) {
 913                         p_end = 0;
 914                         return false;
 915                 }
 916                 p_char[fillnew++] = '=';
 917                 p_context = 100;
 918                 context = 0;
 919                 p_hunk_beg = p_input_line + 1;
 920                 while (fillold <= p_ptrn_lines || fillnew <= p_end) {
 921                         line_beginning = ftell(pfp);
 922                         len = pgets(true);
 923                         p_input_line++;
 924                         if (len == 0) {
 925                                 if (p_max - fillnew < 3) {
 926                                         /* assume blank lines got chopped */
 927                                         strlcpy(buf, " \n", buf_size);
 928                                 } else {
 929                                         fatal("unexpected end of file in patch\n");
 930                                 }
 931                         }
 932                         if (*buf == '\t' || *buf == '\n') {
 933                                 ch = ' ';       /* assume the space got eaten */
 934                                 s = savestr(buf);
 935                         } else {
 936                                 ch = *buf;
 937                                 s = savestr(buf + 1);
 938                         }
 939                         if (out_of_mem) {
 940                                 while (--fillnew > p_ptrn_lines)
 941                                         free(p_line[fillnew]);
 942                                 p_end = fillold - 1;
 943                                 return false;
 944                         }
 945                         switch (ch) {
 946                         case '-':
 947                                 if (fillold > p_ptrn_lines) {
 948                                         free(s);
 949                                         p_end = fillnew - 1;
 950                                         malformed();
 951                                 }
 952                                 p_char[fillold] = ch;
 953                                 p_line[fillold] = s;
 954                                 p_len[fillold++] = strlen(s);
 955                                 if (fillold > p_ptrn_lines) {
 956                                         if (remove_special_line()) {
 957                                                 p_len[fillold - 1] -= 1;
 958                                                 s[p_len[fillold - 1]] = 0;
 959                                         }
 960                                 }
 961                                 break;
 962                         case '=':
 963                                 ch = ' ';
 964                                 /* FALL THROUGH */
 965                         case ' ':
 966                                 if (fillold > p_ptrn_lines) {
 967                                         free(s);
 968                                         while (--fillnew > p_ptrn_lines)
 969                                                 free(p_line[fillnew]);
 970                                         p_end = fillold - 1;
 971                                         malformed();
 972                                 }
 973                                 context++;
 974                                 p_char[fillold] = ch;
 975                                 p_line[fillold] = s;
 976                                 p_len[fillold++] = strlen(s);
 977                                 s = savestr(s);
 978                                 if (out_of_mem) {
 979                                         while (--fillnew > p_ptrn_lines)
 980                                                 free(p_line[fillnew]);
 981                                         p_end = fillold - 1;
 982                                         return false;
 983                                 }
 984                                 if (fillold > p_ptrn_lines) {
 985                                         if (remove_special_line()) {
 986                                                 p_len[fillold - 1] -= 1;
 987                                                 s[p_len[fillold - 1]] = 0;
 988                                         }
 989                                 }
 990                                 /* FALL THROUGH */
 991                         case '+':
 992                                 if (fillnew > p_end) {
 993                                         free(s);
 994                                         while (--fillnew > p_ptrn_lines)
 995                                                 free(p_line[fillnew]);
 996                                         p_end = fillold - 1;
 997                                         malformed();
 998                                 }
 999                                 p_char[fillnew] = ch;
1000                                 p_line[fillnew] = s;
1001                                 p_len[fillnew++] = strlen(s);
1002                                 if (fillold > p_ptrn_lines) {
1003                                         if (remove_special_line()) {
1004                                                 p_len[fillnew - 1] -= 1;
1005                                                 s[p_len[fillnew - 1]] = 0;
1006                                         }
1007                                 }
1008                                 break;
1009                         default:
1010                                 p_end = fillnew;
1011                                 malformed();
1012                         }
1013                         if (ch != ' ' && context > 0) {
1014                                 if (context < p_context)
1015                                         p_context = context;
1016                                 context = -1000;
1017                         }
1018                 }               /* while */
1019         } else {                /* normal diff--fake it up */
1020                 char    hunk_type;
1021                 int     i;
1022                 LINENUM min, max;
1023
1024                 line_beginning = ftell(pfp);
1025                 p_context = 0;
1026                 len = pgets(true);
1027                 p_input_line++;
1028                 if (len == 0 || !isdigit((unsigned char)*buf)) {
1029                         next_intuit_at(line_beginning, p_input_line);
1030                         return false;
1031                 }
1032                 p_first = (LINENUM) atol(buf);
1033                 for (s = buf; isdigit((unsigned char)*s); s++)
1034                         ;
1035                 if (*s == ',') {
1036                         p_ptrn_lines = (LINENUM) atol(++s) - p_first + 1;
1037                         while (isdigit((unsigned char)*s))
1038                                 s++;
1039                 } else
1040                         p_ptrn_lines = (*s != 'a');
1041                 hunk_type = *s;
1042                 if (hunk_type == 'a')
1043                         p_first++;      /* do append rather than insert */
1044                 min = (LINENUM) atol(++s);
1045                 for (; isdigit((unsigned char)*s); s++)
1046                         ;
1047                 if (*s == ',')
1048                         max = (LINENUM) atol(++s);
1049                 else
1050                         max = min;
1051                 if (hunk_type == 'd')
1052                         min++;
1053                 p_end = p_ptrn_lines + 1 + max - min + 1;
1054                 if (p_end > MAXHUNKSIZE)
1055                         fatal("hunk too large (%ld lines) at line %ld: %s",
1056                             p_end, p_input_line, buf);
1057                 while (p_end >= hunkmax)
1058                         grow_hunkmax();
1059                 p_newfirst = min;
1060                 p_repl_lines = max - min + 1;
1061                 snprintf(buf, buf_size, "*** %ld,%ld\n", p_first,
1062                     p_first + p_ptrn_lines - 1);
1063                 p_line[0] = savestr(buf);
1064                 if (out_of_mem) {
1065                         p_end = -1;
1066                         return false;
1067                 }
1068                 p_char[0] = '*';
1069                 for (i = 1; i <= p_ptrn_lines; i++) {
1070                         len = pgets(true);
1071                         p_input_line++;
1072                         if (len == 0)
1073                                 fatal("unexpected end of file in patch at line %ld\n",
1074                                     p_input_line);
1075                         if (*buf != '<')
1076                                 fatal("< expected at line %ld of patch\n",
1077                                     p_input_line);
1078                         p_line[i] = savestr(buf + 2);
1079                         if (out_of_mem) {
1080                                 p_end = i - 1;
1081                                 return false;
1082                         }
1083                         p_len[i] = strlen(p_line[i]);
1084                         p_char[i] = '-';
1085                 }
1086
1087                 if (remove_special_line()) {
1088                         p_len[i - 1] -= 1;
1089                         (p_line[i - 1])[p_len[i - 1]] = 0;
1090                 }
1091                 if (hunk_type == 'c') {
1092                         len = pgets(true);
1093                         p_input_line++;
1094                         if (len == 0)
1095                                 fatal("unexpected end of file in patch at line %ld\n",
1096                                     p_input_line);
1097                         if (*buf != '-')
1098                                 fatal("--- expected at line %ld of patch\n",
1099                                     p_input_line);
1100                 }
1101                 snprintf(buf, buf_size, "--- %ld,%ld\n", min, max);
1102                 p_line[i] = savestr(buf);
1103                 if (out_of_mem) {
1104                         p_end = i - 1;
1105                         return false;
1106                 }
1107                 p_char[i] = '=';
1108                 for (i++; i <= p_end; i++) {
1109                         len = pgets(true);
1110                         p_input_line++;
1111                         if (len == 0)
1112                                 fatal("unexpected end of file in patch at line %ld\n",
1113                                     p_input_line);
1114                         if (*buf != '>')
1115                                 fatal("> expected at line %ld of patch\n",
1116                                     p_input_line);
1117                         p_line[i] = savestr(buf + 2);
1118                         if (out_of_mem) {
1119                                 p_end = i - 1;
1120                                 return false;
1121                         }
1122                         p_len[i] = strlen(p_line[i]);
1123                         p_char[i] = '+';
1124                 }
1125
1126                 if (remove_special_line()) {
1127                         p_len[i - 1] -= 1;
1128                         (p_line[i - 1])[p_len[i - 1]] = 0;
1129                 }
1130         }
1131         if (reverse)            /* backwards patch? */
1132                 if (!pch_swap())
1133                         say("Not enough memory to swap next hunk!\n");
1134 #ifdef DEBUGGING
1135         if (debug & 2) {
1136                 int     i;
1137                 char    special;
1138
1139                 for (i = 0; i <= p_end; i++) {
1140                         if (i == p_ptrn_lines)
1141                                 special = '^';
1142                         else
1143                                 special = ' ';
1144                         fprintf(stderr, "%3d %c %c %s", i, p_char[i],
1145                             special, p_line[i]);
1146                         fflush(stderr);
1147                 }
1148         }
1149 #endif
1150         if (p_end + 1 < hunkmax)/* paranoia reigns supreme... */
1151                 p_char[p_end + 1] = '^';        /* add a stopper for apply_hunk */
1152         return true;
1153 }
1154
1155 /*
1156  * Input a line from the patch file.
1157  * Worry about indentation if do_indent is true.
1158  * The line is read directly into the buf global variable which
1159  * is resized if necessary in order to hold the complete line.
1160  * Returns the number of characters read including the terminating
1161  * '\n', if any.
1162  */
1163 size_t
1164 pgets(bool do_indent)
1165 {
1166         char *line;
1167         size_t len;
1168         int indent = 0, skipped = 0;
1169
1170         line = fgetln(pfp, &len);
1171         if (line != NULL) {
1172                 if (len + 1 > buf_size) {
1173                         while (len + 1 > buf_size)
1174                                 buf_size *= 2;
1175                         free(buf);
1176                         buf = malloc(buf_size);
1177                         if (buf == NULL)
1178                                 fatal("out of memory\n");
1179                 }
1180                 if (do_indent == 1 && p_indent) {
1181                         for (;
1182                             indent < p_indent && (*line == ' ' || *line == '\t' || *line == 'X');
1183                             line++, skipped++) {
1184                                 if (*line == '\t')
1185                                         indent += 8 - (indent %7);
1186                                 else
1187                                         indent++;
1188                         }
1189                 }
1190                 memcpy(buf, line, len - skipped);
1191                 buf[len - skipped] = '\0';
1192         }
1193         return len;
1194 }
1195
1196
1197 /*
1198  * Reverse the old and new portions of the current hunk.
1199  */
1200 bool
1201 pch_swap(void)
1202 {
1203         char    **tp_line;      /* the text of the hunk */
1204         unsigned short  *tp_len;/* length of each line */
1205         char    *tp_char;       /* +, -, and ! */
1206         LINENUM i;
1207         LINENUM n;
1208         bool    blankline = false;
1209         char    *s;
1210
1211         i = p_first;
1212         p_first = p_newfirst;
1213         p_newfirst = i;
1214
1215         /* make a scratch copy */
1216
1217         tp_line = p_line;
1218         tp_len = p_len;
1219         tp_char = p_char;
1220         p_line = NULL;  /* force set_hunkmax to allocate again */
1221         p_len = NULL;
1222         p_char = NULL;
1223         set_hunkmax();
1224         if (p_line == NULL || p_len == NULL || p_char == NULL) {
1225
1226                 free(p_line);
1227                 p_line = tp_line;
1228                 free(p_len);
1229                 p_len = tp_len;
1230                 free(p_char);
1231                 p_char = tp_char;
1232                 return false;   /* not enough memory to swap hunk! */
1233         }
1234         /* now turn the new into the old */
1235
1236         i = p_ptrn_lines + 1;
1237         if (tp_char[i] == '\n') {       /* account for possible blank line */
1238                 blankline = true;
1239                 i++;
1240         }
1241         if (p_efake >= 0) {     /* fix non-freeable ptr range */
1242                 if (p_efake <= i)
1243                         n = p_end - i + 1;
1244                 else
1245                         n = -i;
1246                 p_efake += n;
1247                 p_bfake += n;
1248         }
1249         for (n = 0; i <= p_end; i++, n++) {
1250                 p_line[n] = tp_line[i];
1251                 p_char[n] = tp_char[i];
1252                 if (p_char[n] == '+')
1253                         p_char[n] = '-';
1254                 p_len[n] = tp_len[i];
1255         }
1256         if (blankline) {
1257                 i = p_ptrn_lines + 1;
1258                 p_line[n] = tp_line[i];
1259                 p_char[n] = tp_char[i];
1260                 p_len[n] = tp_len[i];
1261                 n++;
1262         }
1263         if (p_char[0] != '=')
1264                 fatal("Malformed patch at line %ld: expected '=' found '%c'\n",
1265                     p_input_line, p_char[0]);
1266         p_char[0] = '*';
1267         for (s = p_line[0]; *s; s++)
1268                 if (*s == '-')
1269                         *s = '*';
1270
1271         /* now turn the old into the new */
1272
1273         if (p_char[0] != '*')
1274                 fatal("Malformed patch at line %ld: expected '*' found '%c'\n",
1275                     p_input_line, p_char[0]);
1276         tp_char[0] = '=';
1277         for (s = tp_line[0]; *s; s++)
1278                 if (*s == '*')
1279                         *s = '-';
1280         for (i = 0; n <= p_end; i++, n++) {
1281                 p_line[n] = tp_line[i];
1282                 p_char[n] = tp_char[i];
1283                 if (p_char[n] == '-')
1284                         p_char[n] = '+';
1285                 p_len[n] = tp_len[i];
1286         }
1287
1288         if (i != p_ptrn_lines + 1)
1289                 fatal("Malformed patch at line %ld: expected %ld lines, "
1290                     "got %ld\n",
1291                     p_input_line, p_ptrn_lines + 1, i);
1292
1293         i = p_ptrn_lines;
1294         p_ptrn_lines = p_repl_lines;
1295         p_repl_lines = i;
1296
1297         free(tp_line);
1298         free(tp_len);
1299         free(tp_char);
1300
1301         return true;
1302 }
1303
1304 /*
1305  * Return the specified line position in the old file of the old context.
1306  */
1307 LINENUM
1308 pch_first(void)
1309 {
1310         return p_first;
1311 }
1312
1313 /*
1314  * Return the number of lines of old context.
1315  */
1316 LINENUM
1317 pch_ptrn_lines(void)
1318 {
1319         return p_ptrn_lines;
1320 }
1321
1322 /*
1323  * Return the probable line position in the new file of the first line.
1324  */
1325 LINENUM
1326 pch_newfirst(void)
1327 {
1328         return p_newfirst;
1329 }
1330
1331 /*
1332  * Return the number of lines in the replacement text including context.
1333  */
1334 LINENUM
1335 pch_repl_lines(void)
1336 {
1337         return p_repl_lines;
1338 }
1339
1340 /*
1341  * Return the number of lines in the whole hunk.
1342  */
1343 LINENUM
1344 pch_end(void)
1345 {
1346         return p_end;
1347 }
1348
1349 /*
1350  * Return the number of context lines before the first changed line.
1351  */
1352 LINENUM
1353 pch_context(void)
1354 {
1355         return p_context;
1356 }
1357
1358 /*
1359  * Return the length of a particular patch line.
1360  */
1361 unsigned short
1362 pch_line_len(LINENUM line)
1363 {
1364         return p_len[line];
1365 }
1366
1367 /*
1368  * Return the control character (+, -, *, !, etc) for a patch line.
1369  */
1370 char
1371 pch_char(LINENUM line)
1372 {
1373         return p_char[line];
1374 }
1375
1376 /*
1377  * Return a pointer to a particular patch line.
1378  */
1379 char *
1380 pfetch(LINENUM line)
1381 {
1382         return p_line[line];
1383 }
1384
1385 /*
1386  * Return where in the patch file this hunk began, for error messages.
1387  */
1388 LINENUM
1389 pch_hunk_beg(void)
1390 {
1391         return p_hunk_beg;
1392 }
1393
1394 /*
1395  * Apply an ed script by feeding ed itself.
1396  */
1397 void
1398 do_ed_script(void)
1399 {
1400         char    *t;
1401         long    beginning_of_this_line;
1402         FILE    *pipefp = NULL;
1403
1404         if (!skip_rest_of_patch) {
1405                 if (copy_file(filearg[0], TMPOUTNAME) < 0) {
1406                         unlink(TMPOUTNAME);
1407                         fatal("can't create temp file %s", TMPOUTNAME);
1408                 }
1409                 snprintf(buf, buf_size, "%s%s%s", _PATH_ED,
1410                     verbose ? " " : " -s ", TMPOUTNAME);
1411                 pipefp = popen(buf, "w");
1412         }
1413         for (;;) {
1414                 beginning_of_this_line = ftell(pfp);
1415                 if (pgets(true) == 0) {
1416                         next_intuit_at(beginning_of_this_line, p_input_line);
1417                         break;
1418                 }
1419                 p_input_line++;
1420                 for (t = buf; isdigit((unsigned char)*t) || *t == ','; t++)
1421                         ;
1422                 /* POSIX defines allowed commands as {a,c,d,i,s} */
1423                 if (isdigit((unsigned char)*buf) && (*t == 'a' || *t == 'c' ||
1424                     *t == 'd' || *t == 'i' || *t == 's')) {
1425                         if (pipefp != NULL)
1426                                 fputs(buf, pipefp);
1427                         if (*t != 'd') {
1428                                 while (pgets(true)) {
1429                                         p_input_line++;
1430                                         if (pipefp != NULL)
1431                                                 fputs(buf, pipefp);
1432                                         if (strEQ(buf, ".\n"))
1433                                                 break;
1434                                 }
1435                         }
1436                 } else {
1437                         next_intuit_at(beginning_of_this_line, p_input_line);
1438                         break;
1439                 }
1440         }
1441         if (pipefp == NULL)
1442                 return;
1443         fprintf(pipefp, "w\n");
1444         fprintf(pipefp, "q\n");
1445         fflush(pipefp);
1446         pclose(pipefp);
1447         ignore_signals();
1448         if (!check_only) {
1449                 if (move_file(TMPOUTNAME, outname) < 0) {
1450                         toutkeep = true;
1451                         chmod(TMPOUTNAME, filemode);
1452                 } else
1453                         chmod(outname, filemode);
1454         }
1455         set_signals(1);
1456 }
1457
1458 /*
1459  * Choose the name of the file to be patched based on POSIX rules.
1460  * NOTE: the POSIX rules are amazingly stupid and we only follow them
1461  *       if the user specified --posix or set POSIXLY_CORRECT.
1462  */
1463 static char *
1464 posix_name(const struct file_name *names, bool assume_exists)
1465 {
1466         char *path = NULL;
1467         int i;
1468
1469         /*
1470          * POSIX states that the filename will be chosen from one
1471          * of the old, new and index names (in that order) if
1472          * the file exists relative to CWD after -p stripping.
1473          */
1474         for (i = 0; i < MAX_FILE; i++) {
1475                 if (names[i].path != NULL && names[i].exists) {
1476                         path = names[i].path;
1477                         break;
1478                 }
1479         }
1480         if (path == NULL && !assume_exists) {
1481                 /*
1482                  * No files found, look for something we can checkout from
1483                  * RCS/SCCS dirs.  Same order as above.
1484                  */
1485                 for (i = 0; i < MAX_FILE; i++) {
1486                         if (names[i].path != NULL &&
1487                             (path = checked_in(names[i].path)) != NULL)
1488                                 break;
1489                 }
1490                 /*
1491                  * Still no match?  Check to see if the diff could be creating
1492                  * a new file.
1493                  */
1494                 if (path == NULL && ok_to_create_file &&
1495                     names[NEW_FILE].path != NULL)
1496                         path = names[NEW_FILE].path;
1497         }
1498
1499         return path ? savestr(path) : NULL;
1500 }
1501
1502 static char *
1503 compare_names(const struct file_name *names, bool assume_exists, int phase)
1504 {
1505         size_t min_components, min_baselen, min_len, tmp;
1506         char *best = NULL;
1507         char *path;
1508         int i;
1509
1510         /*
1511          * The "best" name is the one with the fewest number of path
1512          * components, the shortest basename length, and the shortest
1513          * overall length (in that order).  We only use the Index: file
1514          * if neither of the old or new files could be intuited from
1515          * the diff header.
1516          */
1517         min_components = min_baselen = min_len = SIZE_MAX;
1518         for (i = INDEX_FILE; i >= OLD_FILE; i--) {
1519                 path = names[i].path;
1520                 if (path == NULL ||
1521                     (phase == 1 && !names[i].exists && !assume_exists) ||
1522                     (phase == 2 && checked_in(path) == NULL))
1523                         continue;
1524                 if ((tmp = num_components(path)) > min_components)
1525                         continue;
1526                 if (tmp < min_components) {
1527                         min_components = tmp;
1528                         best = path;
1529                 }
1530                 if ((tmp = strlen(basename(path))) > min_baselen)
1531                         continue;
1532                 if (tmp < min_baselen) {
1533                         min_baselen = tmp;
1534                         best = path;
1535                 }
1536                 if ((tmp = strlen(path)) > min_len)
1537                         continue;
1538                 min_len = tmp;
1539                 best = path;
1540         }
1541         return best;
1542 }
1543
1544 /*
1545  * Choose the name of the file to be patched based the "best" one
1546  * available.
1547  */
1548 static char *
1549 best_name(const struct file_name *names, bool assume_exists)
1550 {
1551         char *best;
1552
1553         best = compare_names(names, assume_exists, 1);
1554         if (best == NULL) {
1555                 best = compare_names(names, assume_exists, 2);
1556                 /*
1557                  * Still no match?  Check to see if the diff could be creating
1558                  * a new file.
1559                  */
1560                 if (best == NULL && ok_to_create_file &&
1561                     names[NEW_FILE].path != NULL)
1562                         best = names[NEW_FILE].path;
1563         }
1564
1565         return best ? savestr(best) : NULL;
1566 }
1567
1568 static size_t
1569 num_components(const char *path)
1570 {
1571         size_t n;
1572         const char *cp;
1573
1574         for (n = 0, cp = path; (cp = strchr(cp, '/')) != NULL; n++, cp++) {
1575                 while (*cp == '/')
1576                         cp++;           /* skip consecutive slashes */
1577         }
1578         return n;
1579 }