usr.bin/patch/inp.c

   1 /*
   2  * $OpenBSD: inp.c,v 1.34 2006/03/11 19:41:30 otto Exp $
   3  * $DragonFly: src/usr.bin/patch/inp.c,v 1.6 2007/09/29 23:11:10 swildner Exp $
   4  */
   5
   6 /*
   7  * patch - a program to apply diffs to original files
   8  *
   9  * Copyright 1986, Larry Wall
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following condition is met:
  13  * 1. Redistributions of source code must retain the above copyright notice,
  14  * this condition and the following disclaimer.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
  17  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  18  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  19  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  20  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  22  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  23  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  26  * SUCH DAMAGE.
  27  *
  28  * -C option added in 1998, original code by Marc Espie, based on FreeBSD
  29  * behaviour
  30  */
  31
  32 #include <sys/types.h>
  33 #include <sys/file.h>
  34 #include <sys/stat.h>
  35 #include <sys/mman.h>
  36
  37 #include <ctype.h>
  38 #include <libgen.h>
  39 #include <limits.h>
  40 #include <stddef.h>
  41 #include <stdio.h>
  42 #include <stdlib.h>
  43 #include <string.h>
  44 #include <unistd.h>
  45
  46 #include "common.h"
  47 #include "util.h"
  48 #include "pch.h"
  49 #include "inp.h"
  50
  51
  52 /* Input-file-with-indexable-lines abstract type */
  53
  54 static off_t    i_size;         /* size of the input file */
  55 static char     *i_womp;        /* plan a buffer for entire file */
  56 static char     **i_ptr;        /* pointers to lines in i_womp */
  57 static char     empty_line[] = { '\0' };
  58
  59 static int      tifd = -1;      /* plan b virtual string array */
  60 static char     *tibuf[2];      /* plan b buffers */
  61 static LINENUM  tiline[2] = {-1, -1};   /* 1st line in each buffer */
  62 static LINENUM  lines_per_buf;  /* how many lines per buffer */
  63 static int      tireclen;       /* length of records in tmp file */
  64
  65 static bool     rev_in_string(const char *);
  66 static bool     reallocate_lines(size_t *);
  67
  68 /* returns false if insufficient memory */
  69 static bool     plan_a(const char *);
  70
  71 static void     plan_b(const char *);
  72
  73 /* New patch--prepare to edit another file. */
  74
  75 void
  76 re_input(void)
  77 {
  78         if (using_plan_a) {
  79                 i_size = 0;
  80                 free(i_ptr);
  81                 i_ptr = NULL;
  82                 if (i_womp != NULL) {
  83                         munmap(i_womp, i_size);
  84                         i_womp = NULL;
  85                 }
  86         } else {
  87                 using_plan_a = true;    /* maybe the next one is smaller */
  88                 close(tifd);
  89                 tifd = -1;
  90                 free(tibuf[0]);
  91                 free(tibuf[1]);
  92                 tibuf[0] = tibuf[1] = NULL;
  93                 tiline[0] = tiline[1] = -1;
  94                 tireclen = 0;
  95         }
  96 }
  97
  98 /* Construct the line index, somehow or other. */
  99
 100 void
 101 scan_input(const char *filename)
 102 {
 103         if (!plan_a(filename))
 104                 plan_b(filename);
 105         if (verbose) {
 106                 say("Patching file %s using Plan %s...\n", filename,
 107                     (using_plan_a ? "A" : "B"));
 108         }
 109 }
 110
 111 static bool
 112 reallocate_lines(size_t *lines_allocated)
 113 {
 114         char    **p;
 115         size_t  new_size;
 116
 117         new_size = *lines_allocated * 3 / 2;
 118         p = realloc(i_ptr, (new_size + 2) * sizeof(char *));
 119         if (p == NULL) {        /* shucks, it was a near thing */
 120                 munmap(i_womp, i_size);
 121                 i_womp = NULL;
 122                 free(i_ptr);
 123                 i_ptr = NULL;
 124                 *lines_allocated = 0;
 125                 return false;
 126         }
 127         *lines_allocated = new_size;
 128         i_ptr = p;
 129         return true;
 130 }
 131
 132 /* Try keeping everything in memory. */
 133
 134 static bool
 135 plan_a(const char *filename)
 136 {
 137         int             ifd, statfailed;
 138         char            *p, *s, lbuf[MAXLINELEN];
 139         struct stat     filestat;
 140         off_t           i;
 141         ptrdiff_t       sz;
 142         size_t          iline, lines_allocated;
 143
 144 #ifdef DEBUGGING
 145         if (debug & 8)
 146                 return false;
 147 #endif
 148
 149         if (filename == NULL || *filename == '\0')
 150                 return false;
 151
 152         statfailed = stat(filename, &filestat);
 153         if (statfailed && ok_to_create_file) {
 154                 if (verbose)
 155                         say("(Creating file %s...)\n", filename);
 156
 157                 /*
 158                  * in check_patch case, we still display `Creating file' even
 159                  * though we're not. The rule is that -C should be as similar
 160                  * to normal patch behavior as possible
 161                  */
 162                 if (check_only)
 163                         return true;
 164                 makedirs(filename, true);
 165                 close(creat(filename, 0666));
 166                 statfailed = stat(filename, &filestat);
 167         }
 168         if (statfailed && check_only)
 169                 fatal("%s not found, -C mode, can't probe further\n", filename);
 170         /* For nonexistent or read-only files, look for RCS or SCCS versions.  */
 171         if (statfailed ||
 172             /* No one can write to it.  */
 173             (filestat.st_mode & 0222) == 0 ||
 174             /* I can't write to it.  */
 175             ((filestat.st_mode & 0022) == 0 && filestat.st_uid != getuid())) {
 176                 const char      *cs = NULL, *filebase, *filedir;
 177                 struct stat     cstat;
 178                 char *tmp_filename1, *tmp_filename2;
 179
 180                 tmp_filename1 = strdup(filename);
 181                 tmp_filename2 = strdup(filename);
 182                 if (tmp_filename1 == NULL || tmp_filename2 == NULL)
 183                         fatal("strdupping filename");
 184                 filebase = basename(tmp_filename1);
 185                 filedir = dirname(tmp_filename2);
 186
 187                 /* Leave room in lbuf for the diff command.  */
 188                 s = lbuf + 20;
 189
 190 #define try(f, a1, a2, a3) \
 191         (snprintf(s, sizeof lbuf - 20, f, a1, a2, a3), stat(s, &cstat) == 0)
 192
 193                 if (try("%s/RCS/%s%s", filedir, filebase, RCSSUFFIX) ||
 194                     try("%s/RCS/%s%s", filedir, filebase, "") ||
 195                     try("%s/%s%s", filedir, filebase, RCSSUFFIX)) {
 196                         snprintf(buf, buf_len, CHECKOUT, filename);
 197                         snprintf(lbuf, sizeof lbuf, RCSDIFF, filename);
 198                         cs = "RCS";
 199                 } else if (try("%s/SCCS/%s%s", filedir, SCCSPREFIX, filebase) ||
 200                     try("%s/%s%s", filedir, SCCSPREFIX, filebase)) {
 201                         snprintf(buf, buf_len, GET, s);
 202                         snprintf(lbuf, sizeof lbuf, SCCSDIFF, s, filename);
 203                         cs = "SCCS";
 204                 } else if (statfailed)
 205                         fatal("can't find %s\n", filename);
 206
 207                 free(tmp_filename1);
 208                 free(tmp_filename2);
 209
 210                 /*
 211                  * else we can't write to it but it's not under a version
 212                  * control system, so just proceed.
 213                  */
 214                 if (cs) {
 215                         if (!statfailed) {
 216                                 if ((filestat.st_mode & 0222) != 0)
 217                                         /* The owner can write to it.  */
 218                                         fatal("file %s seems to be locked "
 219                                             "by somebody else under %s\n",
 220                                             filename, cs);
 221                                 /*
 222                                  * It might be checked out unlocked.  See if
 223                                  * it's safe to check out the default version
 224                                  * locked.
 225                                  */
 226                                 if (verbose)
 227                                         say("Comparing file %s to default "
 228                                             "%s version...\n",
 229                                             filename, cs);
 230                                 if (system(lbuf))
 231                                         fatal("can't check out file %s: "
 232                                             "differs from default %s version\n",
 233                                             filename, cs);
 234                         }
 235                         if (verbose)
 236                                 say("Checking out file %s from %s...\n",
 237                                     filename, cs);
 238                         if (system(buf) || stat(filename, &filestat))
 239                                 fatal("can't check out file %s from %s\n",
 240                                     filename, cs);
 241                 }
 242         }
 243         filemode = filestat.st_mode;
 244         if (!S_ISREG(filemode))
 245                 fatal("%s is not a normal file--can't patch\n", filename);
 246         i_size = filestat.st_size;
 247         if (out_of_mem) {
 248                 set_hunkmax();  /* make sure dynamic arrays are allocated */
 249                 out_of_mem = false;
 250                 return false;   /* force plan b because plan a bombed */
 251         }
 252         if (i_size > SIZE_MAX) {
 253                 say("block too large to mmap\n");
 254                 return false;
 255         }
 256         if ((ifd = open(filename, O_RDONLY)) < 0)
 257                 pfatal("can't open file %s", filename);
 258
 259         i_womp = mmap(NULL, i_size, PROT_READ, MAP_PRIVATE, ifd, 0);
 260         if (i_womp == MAP_FAILED) {
 261                 perror("mmap failed");
 262                 i_womp = NULL;
 263                 close(ifd);
 264                 return false;
 265         }
 266
 267         close(ifd);
 268         if (i_size)
 269                 madvise(i_womp, i_size, MADV_SEQUENTIAL);
 270
 271         /* estimate the number of lines */
 272         lines_allocated = i_size / 25;
 273         if (lines_allocated < 100)
 274                 lines_allocated = 100;
 275
 276         if (!reallocate_lines(&lines_allocated))
 277                 return false;
 278
 279         /* now scan the buffer and build pointer array */
 280         iline = 1;
 281         i_ptr[iline] = i_womp;
 282         /* test for NUL too, to maintain the behavior of the original code */
 283         for (s = i_womp, i = 0; i < i_size && *s != '\0'; s++, i++) {
 284                 if (*s == '\n') {
 285                         if (iline == lines_allocated) {
 286                                 if (!reallocate_lines(&lines_allocated))
 287                                         return false;
 288                         }
 289                         /* these are NOT NUL terminated */
 290                         i_ptr[++iline] = s + 1;
 291                 }
 292         }
 293         /* if the last line contains no EOL, append one */
 294         if (i_size > 0 && i_womp[i_size - 1] != '\n') {
 295                 last_line_missing_eol = true;
 296                 /* fix last line */
 297                 sz = s - i_ptr[iline];
 298                 p = malloc(sz + 1);
 299                 if (p == NULL) {
 300                         free(i_ptr);
 301                         i_ptr = NULL;
 302                         munmap(i_womp, i_size);
 303                         i_womp = NULL;
 304                         return false;
 305                 }
 306
 307                 memcpy(p, i_ptr[iline], sz);
 308                 p[sz] = '\n';
 309                 i_ptr[iline] = p;
 310                 /* count the extra line and make it point to some valid mem */
 311                 i_ptr[++iline] = empty_line;
 312         } else
 313                 last_line_missing_eol = false;
 314
 315         input_lines = iline - 1;
 316
 317         /* now check for revision, if any */
 318
 319         if (revision != NULL) {
 320                 if (!rev_in_string(i_womp)) {
 321                         if (force) {
 322                                 if (verbose)
 323                                         say("Warning: this file doesn't appear "
 324                                             "to be the %s version--patching anyway.\n",
 325                                             revision);
 326                         } else if (batch) {
 327                                 fatal("this file doesn't appear to be the "
 328                                     "%s version--aborting.\n",
 329                                     revision);
 330                         } else {
 331                                 ask("This file doesn't appear to be the "
 332                                     "%s version--patch anyway? [n] ",
 333                                     revision);
 334                                 if (*buf != 'y')
 335                                         fatal("aborted\n");
 336                         }
 337                 } else if (verbose)
 338                         say("Good.  This file appears to be the %s version.\n",
 339                             revision);
 340         }
 341         return true;            /* plan a will work */
 342 }
 343
 344 /* Keep (virtually) nothing in memory. */
 345
 346 static void
 347 plan_b(const char *filename)
 348 {
 349         FILE    *ifp;
 350         size_t  i = 0, j, maxlen = 1;
 351         char    *p;
 352         bool    found_revision = (revision == NULL);
 353
 354         using_plan_a = false;
 355         if ((ifp = fopen(filename, "r")) == NULL)
 356                 pfatal("can't open file %s", filename);
 357         unlink(TMPINNAME);
 358         if ((tifd = open(TMPINNAME, O_EXCL | O_CREAT | O_WRONLY, 0666)) < 0)
 359                 pfatal("can't open file %s", TMPINNAME);
 360         while (fgets(buf, buf_len, ifp) != NULL) {
 361                 if (revision != NULL && !found_revision && rev_in_string(buf))
 362                         found_revision = true;
 363                 if ((i = strlen(buf)) > maxlen)
 364                         maxlen = i;     /* find longest line */
 365         }
 366         last_line_missing_eol = i > 0 && buf[i - 1] != '\n';
 367         if (last_line_missing_eol && maxlen == i)
 368                 maxlen++;
 369
 370         if (revision != NULL) {
 371                 if (!found_revision) {
 372                         if (force) {
 373                                 if (verbose)
 374                                         say("Warning: this file doesn't appear "
 375                                             "to be the %s version--patching anyway.\n",
 376                                             revision);
 377                         } else if (batch) {
 378                                 fatal("this file doesn't appear to be the "
 379                                     "%s version--aborting.\n",
 380                                     revision);
 381                         } else {
 382                                 ask("This file doesn't appear to be the %s "
 383                                     "version--patch anyway? [n] ",
 384                                     revision);
 385                                 if (*buf != 'y')
 386                                         fatal("aborted\n");
 387                         }
 388                 } else if (verbose)
 389                         say("Good.  This file appears to be the %s version.\n",
 390                             revision);
 391         }
 392         fseek(ifp, 0L, SEEK_SET);       /* rewind file */
 393         lines_per_buf = BUFFERSIZE / maxlen;
 394         tireclen = maxlen;
 395         tibuf[0] = malloc(BUFFERSIZE + 1);
 396         if (tibuf[0] == NULL)
 397                 fatal("out of memory\n");
 398         tibuf[1] = malloc(BUFFERSIZE + 1);
 399         if (tibuf[1] == NULL)
 400                 fatal("out of memory\n");
 401         for (i = 1;; i++) {
 402                 p = tibuf[0] + maxlen * (i % lines_per_buf);
 403                 if (i % lines_per_buf == 0)     /* new block */
 404                         if (write(tifd, tibuf[0], BUFFERSIZE) < BUFFERSIZE)
 405                                 pfatal("can't write temp file");
 406                 if (fgets(p, maxlen + 1, ifp) == NULL) {
 407                         input_lines = i - 1;
 408                         if (i % lines_per_buf != 0)
 409                                 if (write(tifd, tibuf[0], BUFFERSIZE) < BUFFERSIZE)
 410                                         pfatal("can't write temp file");
 411                         break;
 412                 }
 413                 j = strlen(p);
 414                 /* These are '\n' terminated strings, so no need to add a NUL */
 415                 if (j == 0 || p[j - 1] != '\n')
 416                         p[j] = '\n';
 417         }
 418         fclose(ifp);
 419         close(tifd);
 420         if ((tifd = open(TMPINNAME, O_RDONLY)) < 0)
 421                 pfatal("can't reopen file %s", TMPINNAME);
 422 }
 423
 424 /*
 425  * Fetch a line from the input file, \n terminated, not necessarily \0.
 426  */
 427 char *
 428 ifetch(LINENUM line, int whichbuf)
 429 {
 430         if (line < 1 || line > input_lines) {
 431                 if (warn_on_invalid_line) {
 432                         say("No such line %ld in input file, ignoring\n", line);
 433                         warn_on_invalid_line = false;
 434                 }
 435                 return NULL;
 436         }
 437         if (using_plan_a)
 438                 return i_ptr[line];
 439         else {
 440                 LINENUM offline = line % lines_per_buf;
 441                 LINENUM baseline = line - offline;
 442
 443                 if (tiline[0] == baseline)
 444                         whichbuf = 0;
 445                 else if (tiline[1] == baseline)
 446                         whichbuf = 1;
 447                 else {
 448                         tiline[whichbuf] = baseline;
 449
 450                         if (lseek(tifd, (off_t) (baseline / lines_per_buf *
 451                             BUFFERSIZE), SEEK_SET) < 0)
 452                                 pfatal("cannot seek in the temporary input file");
 453
 454                         if (read(tifd, tibuf[whichbuf], BUFFERSIZE) < 0)
 455                                 pfatal("error reading tmp file %s", TMPINNAME);
 456                 }
 457                 return tibuf[whichbuf] + (tireclen * offline);
 458         }
 459 }
 460
 461 /*
 462  * True if the string argument contains the revision number we want.
 463  */
 464 static bool
 465 rev_in_string(const char *string)
 466 {
 467         const char      *s;
 468         size_t          patlen;
 469
 470         if (revision == NULL)
 471                 return true;
 472         patlen = strlen(revision);
 473         if (strnEQ(string, revision, patlen) && isspace((unsigned char)string[patlen]))
 474                 return true;
 475         for (s = string; *s; s++) {
 476                 if (isspace((unsigned char)*s) && strnEQ(s + 1, revision, patlen) &&
 477                     isspace((unsigned char)s[patlen + 1])) {
 478                         return true;
 479                 }
 480         }
 481         return false;
 482 }