commands/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  * $NetBSD: inp.c,v 1.19 2008/09/19 18:33:34 joerg Exp $
   5  */
   6
   7 /*
   8  * patch - a program to apply diffs to original files
   9  *
  10  * Copyright 1986, Larry Wall
  11  *
  12  * Redistribution and use in source and binary forms, with or without
  13  * modification, are permitted provided that the following condition is met:
  14  * 1. Redistributions of source code must retain the above copyright notice,
  15  * this condition and the following disclaimer.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
  18  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  19  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  20  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  21  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  23  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  24  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  *
  29  * -C option added in 1998, original code by Marc Espie, based on FreeBSD
  30  * behaviour
  31  */
  32
  33 #include <sys/cdefs.h>
  34
  35 #include <sys/types.h>
  36 #include <sys/file.h>
  37 #include <sys/stat.h>
  38 #include <sys/mman.h>
  39
  40 #include <ctype.h>
  41 #include <libgen.h>
  42 #include <limits.h>
  43 #include <stddef.h>
  44 #include <stdio.h>
  45 #include <stdlib.h>
  46 #include <string.h>
  47 #include <unistd.h>
  48 #include <fcntl.h>
  49
  50 #include "common.h"
  51 #include "util.h"
  52 #include "pch.h"
  53 #include "inp.h"
  54
  55
  56 /* Input-file-with-indexable-lines abstract type */
  57
  58 static off_t    i_size;         /* size of the input file */
  59 static char     *i_womp;        /* plan a buffer for entire file */
  60 static char     **i_ptr;        /* pointers to lines in i_womp */
  61 static char     empty_line[] = { '\0' };
  62
  63 static int      tifd = -1;      /* plan b virtual string array */
  64 static char     *tibuf[2];      /* plan b buffers */
  65 static LINENUM  tiline[2] = {-1, -1};   /* 1st line in each buffer */
  66 static LINENUM  lines_per_buf;  /* how many lines per buffer */
  67 static int      tireclen;       /* length of records in tmp file */
  68
  69 static bool     rev_in_string(const char *);
  70 static bool     reallocate_lines(size_t *);
  71
  72 /* returns false if insufficient memory */
  73 static bool     plan_a(const char *);
  74
  75 static void     plan_b(const char *);
  76
  77 static int readfile(int fd, char *buf, size_t s)
  78 {
  79         int ntoread, nread;
  80
  81         ntoread = s;
  82         nread = 0;
  83
  84         while(ntoread > 0) {
  85                 if((nread = read(fd, buf, ntoread)) < 0) {
  86                         return nread;
  87                 }
  88                 buf += nread;
  89                 ntoread -= nread;
  90         }
  91
  92         return 0;
  93 }
  94
  95 /* New patch--prepare to edit another file. */
  96
  97 void
  98 re_input(void)
  99 {
 100         if (using_plan_a) {
 101                 i_size = 0;
 102                 free(i_ptr);
 103                 i_ptr = NULL;
 104                 if (i_womp != NULL) {
 105 #ifndef __minix
 106                         munmap(i_womp, i_size);
 107 #else
 108                         free(i_womp);
 109 #endif
 110                         i_womp = NULL;
 111                 }
 112         } else {
 113                 using_plan_a = true;    /* maybe the next one is smaller */
 114                 close(tifd);
 115                 tifd = -1;
 116                 free(tibuf[0]);
 117                 free(tibuf[1]);
 118                 tibuf[0] = tibuf[1] = NULL;
 119                 tiline[0] = tiline[1] = -1;
 120                 tireclen = 0;
 121         }
 122 }
 123
 124 /* Construct the line index, somehow or other. */
 125
 126 void
 127 scan_input(const char *filename)
 128 {
 129         if (!plan_a(filename))
 130                 plan_b(filename);
 131         if (verbose) {
 132                 say("Patching file %s using Plan %s...\n", filename,
 133                     (using_plan_a ? "A" : "B"));
 134         }
 135 }
 136
 137 static bool
 138 reallocate_lines(size_t *lines_allocated)
 139 {
 140         char    **p;
 141         size_t  new_size;
 142
 143         new_size = *lines_allocated * 3 / 2;
 144         p = realloc(i_ptr, (new_size + 2) * sizeof(char *));
 145         if (p == NULL) {        /* shucks, it was a near thing */
 146 #ifndef __minix
 147                 munmap(i_womp, i_size);
 148 #else
 149                 free(i_womp);
 150 #endif
 151                 i_womp = NULL;
 152                 free(i_ptr);
 153                 i_ptr = NULL;
 154                 *lines_allocated = 0;
 155                 return false;
 156         }
 157         *lines_allocated = new_size;
 158         i_ptr = p;
 159         return true;
 160 }
 161
 162 /* Try keeping everything in memory. */
 163
 164 static bool
 165 plan_a(const char *filename)
 166 {
 167         int             ifd, statfailed;
 168         char            *p, *s, lbuf[MAXLINELEN];
 169         struct stat     filestat;
 170         off_t           i;
 171         ptrdiff_t       sz;
 172         size_t          iline, lines_allocated;
 173
 174 #ifdef DEBUGGING
 175         if (debug & 8)
 176                 return false;
 177 #endif
 178
 179         if (filename == NULL || *filename == '\0')
 180                 return false;
 181
 182         statfailed = stat(filename, &filestat);
 183         if (statfailed && ok_to_create_file) {
 184                 if (verbose)
 185                         say("(Creating file %s...)\n", filename);
 186
 187                 /*
 188                  * in check_patch case, we still display `Creating file' even
 189                  * though we're not. The rule is that -C should be as similar
 190                  * to normal patch behavior as possible
 191                  */
 192                 if (check_only)
 193                         return true;
 194                 makedirs(filename, true);
 195                 close(creat(filename, 0666));
 196                 statfailed = stat(filename, &filestat);
 197         }
 198         if (statfailed && check_only)
 199                 fatal("%s not found, -C mode, can't probe further\n", filename);
 200         /* For nonexistent or read-only files, look for RCS or SCCS versions.  */
 201         if (statfailed ||
 202             /* No one can write to it.  */
 203             (filestat.st_mode & 0222) == 0 ||
 204             /* I can't write to it.  */
 205             ((filestat.st_mode & 0022) == 0 && filestat.st_uid != getuid())) {
 206                 const char      *cs = NULL, *filebase, *filedir;
 207                 struct stat     cstat;
 208                 char *tmp_filename1, *tmp_filename2;
 209
 210                 tmp_filename1 = strdup(filename);
 211                 tmp_filename2 = strdup(filename);
 212                 if (tmp_filename1 == NULL || tmp_filename2 == NULL)
 213                         fatal("strdupping filename");
 214                 filebase = basename(tmp_filename1);
 215                 filedir = dirname(tmp_filename2);
 216
 217                 /* Leave room in lbuf for the diff command.  */
 218                 s = lbuf + 20;
 219
 220 #define try(f, a1, a2, a3) \
 221         (snprintf(s, sizeof lbuf - 20, f, a1, a2, a3), stat(s, &cstat) == 0)
 222
 223                 if (try("%s/RCS/%s%s", filedir, filebase, RCSSUFFIX) ||
 224                     try("%s/RCS/%s%s", filedir, filebase, "") ||
 225                     try("%s/%s%s", filedir, filebase, RCSSUFFIX)) {
 226                         snprintf(buf, buf_len, CHECKOUT, filename);
 227                         snprintf(lbuf, sizeof lbuf, RCSDIFF, filename);
 228                         cs = "RCS";
 229                 } else if (try("%s/SCCS/%s%s", filedir, SCCSPREFIX, filebase) ||
 230                     try("%s/%s%s", filedir, SCCSPREFIX, filebase)) {
 231                         snprintf(buf, buf_len, GET, s);
 232                         snprintf(lbuf, sizeof lbuf, SCCSDIFF, s, filename);
 233                         cs = "SCCS";
 234                 } else if (statfailed)
 235                         fatal("can't find %s\n", filename);
 236
 237                 free(tmp_filename1);
 238                 free(tmp_filename2);
 239
 240                 /*
 241                  * else we can't write to it but it's not under a version
 242                  * control system, so just proceed.
 243                  */
 244                 if (cs) {
 245                         if (!statfailed) {
 246                                 if ((filestat.st_mode & 0222) != 0)
 247                                         /* The owner can write to it.  */
 248                                         fatal("file %s seems to be locked "
 249                                             "by somebody else under %s\n",
 250                                             filename, cs);
 251                                 /*
 252                                  * It might be checked out unlocked.  See if
 253                                  * it's safe to check out the default version
 254                                  * locked.
 255                                  */
 256                                 if (verbose)
 257                                         say("Comparing file %s to default "
 258                                             "%s version...\n",
 259                                             filename, cs);
 260                                 if (system(lbuf))
 261                                         fatal("can't check out file %s: "
 262                                             "differs from default %s version\n",
 263                                             filename, cs);
 264                         }
 265                         if (verbose)
 266                                 say("Checking out file %s from %s...\n",
 267                                     filename, cs);
 268                         if (system(buf) || stat(filename, &filestat))
 269                                 fatal("can't check out file %s from %s\n",
 270                                     filename, cs);
 271                 }
 272         }
 273         filemode = filestat.st_mode;
 274         if (!S_ISREG(filemode))
 275                 fatal("%s is not a normal file--can't patch\n", filename);
 276         i_size = filestat.st_size;
 277         if (out_of_mem) {
 278                 set_hunkmax();  /* make sure dynamic arrays are allocated */
 279                 out_of_mem = false;
 280                 return false;   /* force plan b because plan a bombed */
 281         }
 282 #ifndef __minix
 283         if (i_size > SIZE_MAX) {
 284                 say("block too large to mmap\n");
 285                 return false;
 286         }
 287 #endif
 288         if ((ifd = open(filename, O_RDONLY)) < 0)
 289                 pfatal("can't open file %s", filename);
 290
 291 #ifndef __minix
 292         i_womp = mmap(NULL, i_size, PROT_READ, MAP_PRIVATE, ifd, 0);
 293         if (i_womp == MAP_FAILED) {
 294                 perror("mmap failed");
 295                 i_womp = NULL;
 296                 close(ifd);
 297                 return false;
 298         }
 299 #else
 300         i_womp = malloc(i_size);
 301         if(i_size && i_womp == NULL) {
 302                 fprintf(stderr, "Malloc failed.\n");
 303                 i_womp = NULL;
 304                 close(ifd);
 305                 return false;
 306         }
 307         if(readfile(ifd, i_womp, i_size) < 0) {
 308                 perror("Readfile failed.");
 309                 i_womp = NULL;
 310                 close(ifd);
 311                 return false;
 312         }
 313 #endif
 314
 315         close(ifd);
 316 #ifndef __minix
 317         if (i_size)
 318                 madvise(i_womp, i_size, MADV_SEQUENTIAL);
 319 #endif
 320
 321         /* estimate the number of lines */
 322         lines_allocated = i_size / 25;
 323         if (lines_allocated < 100)
 324                 lines_allocated = 100;
 325
 326         if (!reallocate_lines(&lines_allocated))
 327                 return false;
 328
 329         /* now scan the buffer and build pointer array */
 330         iline = 1;
 331         i_ptr[iline] = i_womp;
 332         /* test for NUL too, to maintain the behavior of the original code */
 333         for (s = i_womp, i = 0; i < i_size && *s != '\0'; s++, i++) {
 334                 if (*s == '\n') {
 335                         if (iline == lines_allocated) {
 336                                 if (!reallocate_lines(&lines_allocated))
 337                                         return false;
 338                         }
 339                         /* these are NOT NUL terminated */
 340                         i_ptr[++iline] = s + 1;
 341                 }
 342         }
 343         /* if the last line contains no EOL, append one */
 344         if (i_size > 0 && i_womp[i_size - 1] != '\n') {
 345                 last_line_missing_eol = true;
 346                 /* fix last line */
 347                 sz = s - i_ptr[iline];
 348                 p = malloc(sz + 1);
 349                 if (p == NULL) {
 350                         free(i_ptr);
 351                         i_ptr = NULL;
 352 #ifndef __minix
 353                         munmap(i_womp, i_size);
 354 #else
 355                         free(i_womp);
 356 #endif
 357                         i_womp = NULL;
 358                         return false;
 359                 }
 360
 361                 memcpy(p, i_ptr[iline], sz);
 362                 p[sz] = '\n';
 363                 i_ptr[iline] = p;
 364                 /* count the extra line and make it point to some valid mem */
 365                 i_ptr[++iline] = empty_line;
 366         } else
 367                 last_line_missing_eol = false;
 368
 369         input_lines = iline - 1;
 370
 371         /* now check for revision, if any */
 372
 373         if (revision != NULL) {
 374                 if (!rev_in_string(i_womp)) {
 375                         if (force) {
 376                                 if (verbose)
 377                                         say("Warning: this file doesn't appear "
 378                                             "to be the %s version--patching anyway.\n",
 379                                             revision);
 380                         } else if (batch) {
 381                                 fatal("this file doesn't appear to be the "
 382                                     "%s version--aborting.\n",
 383                                     revision);
 384                         } else {
 385                                 ask("This file doesn't appear to be the "
 386                                     "%s version--patch anyway? [n] ",
 387                                     revision);
 388                                 if (*buf != 'y')
 389                                         fatal("aborted\n");
 390                         }
 391                 } else if (verbose)
 392                         say("Good.  This file appears to be the %s version.\n",
 393                             revision);
 394         }
 395         return true;            /* plan a will work */
 396 }
 397
 398 /* Keep (virtually) nothing in memory. */
 399
 400 static void
 401 plan_b(const char *filename)
 402 {
 403         FILE    *ifp;
 404         size_t  i = 0, j, maxlen = 1;
 405         char    *p;
 406         bool    found_revision = (revision == NULL);
 407
 408         using_plan_a = false;
 409         if ((ifp = fopen(filename, "r")) == NULL)
 410                 pfatal("can't open file %s", filename);
 411         unlink(TMPINNAME);
 412         if ((tifd = open(TMPINNAME, O_EXCL | O_CREAT | O_WRONLY, 0666)) < 0)
 413                 pfatal("can't open file %s", TMPINNAME);
 414         while (fgets(buf, buf_len, ifp) != NULL) {
 415                 if (revision != NULL && !found_revision && rev_in_string(buf))
 416                         found_revision = true;
 417                 if ((i = strlen(buf)) > maxlen)
 418                         maxlen = i;     /* find longest line */
 419         }
 420         last_line_missing_eol = i > 0 && buf[i - 1] != '\n';
 421         if (last_line_missing_eol && maxlen == i)
 422                 maxlen++;
 423
 424         if (revision != NULL) {
 425                 if (!found_revision) {
 426                         if (force) {
 427                                 if (verbose)
 428                                         say("Warning: this file doesn't appear "
 429                                             "to be the %s version--patching anyway.\n",
 430                                             revision);
 431                         } else if (batch) {
 432                                 fatal("this file doesn't appear to be the "
 433                                     "%s version--aborting.\n",
 434                                     revision);
 435                         } else {
 436                                 ask("This file doesn't appear to be the %s "
 437                                     "version--patch anyway? [n] ",
 438                                     revision);
 439                                 if (*buf != 'y')
 440                                         fatal("aborted\n");
 441                         }
 442                 } else if (verbose)
 443                         say("Good.  This file appears to be the %s version.\n",
 444                             revision);
 445         }
 446         fseek(ifp, 0L, SEEK_SET);       /* rewind file */
 447         lines_per_buf = BUFFERSIZE / maxlen;
 448         tireclen = maxlen;
 449         tibuf[0] = malloc(BUFFERSIZE + 1);
 450         if (tibuf[0] == NULL)
 451                 fatal("out of memory\n");
 452         tibuf[1] = malloc(BUFFERSIZE + 1);
 453         if (tibuf[1] == NULL)
 454                 fatal("out of memory\n");
 455         for (i = 1;; i++) {
 456                 p = tibuf[0] + maxlen * (i % lines_per_buf);
 457                 if (i % lines_per_buf == 0)     /* new block */
 458                         if (write(tifd, tibuf[0], BUFFERSIZE) < BUFFERSIZE)
 459                                 pfatal("can't write temp file");
 460                 if (fgets(p, maxlen + 1, ifp) == NULL) {
 461                         input_lines = i - 1;
 462                         if (i % lines_per_buf != 0)
 463                                 if (write(tifd, tibuf[0], BUFFERSIZE) < BUFFERSIZE)
 464                                         pfatal("can't write temp file");
 465                         break;
 466                 }
 467                 j = strlen(p);
 468                 /* These are '\n' terminated strings, so no need to add a NUL */
 469                 if (j == 0 || p[j - 1] != '\n')
 470                         p[j] = '\n';
 471         }
 472         fclose(ifp);
 473         close(tifd);
 474         if ((tifd = open(TMPINNAME, O_RDONLY)) < 0)
 475                 pfatal("can't reopen file %s", TMPINNAME);
 476 }
 477
 478 /*
 479  * Fetch a line from the input file, \n terminated, not necessarily \0.
 480  */
 481 char *
 482 ifetch(LINENUM line, int whichbuf)
 483 {
 484         if (line < 1 || line > input_lines) {
 485                 if (warn_on_invalid_line) {
 486                         say("No such line %ld in input file, ignoring\n", line);
 487                         warn_on_invalid_line = false;
 488                 }
 489                 return NULL;
 490         }
 491         if (using_plan_a)
 492                 return i_ptr[line];
 493         else {
 494                 LINENUM offline = line % lines_per_buf;
 495                 LINENUM baseline = line - offline;
 496
 497                 if (tiline[0] == baseline)
 498                         whichbuf = 0;
 499                 else if (tiline[1] == baseline)
 500                         whichbuf = 1;
 501                 else {
 502                         tiline[whichbuf] = baseline;
 503
 504                         if (lseek(tifd, (off_t) (baseline / lines_per_buf *
 505                             BUFFERSIZE), SEEK_SET) < 0)
 506                                 pfatal("cannot seek in the temporary input file");
 507
 508                         if (read(tifd, tibuf[whichbuf], BUFFERSIZE) < 0)
 509                                 pfatal("error reading tmp file %s", TMPINNAME);
 510                 }
 511                 return tibuf[whichbuf] + (tireclen * offline);
 512         }
 513 }
 514
 515 /*
 516  * True if the string argument contains the revision number we want.
 517  */
 518 static bool
 519 rev_in_string(const char *string)
 520 {
 521         const char      *s;
 522         size_t          patlen;
 523
 524         if (revision == NULL)
 525                 return true;
 526         patlen = strlen(revision);
 527         if (strnEQ(string, revision, patlen) && isspace((unsigned char)string[patlen]))
 528                 return true;
 529         for (s = string; *s; s++) {
 530                 if (isspace((unsigned char)*s) && strnEQ(s + 1, revision, patlen) &&
 531                     isspace((unsigned char)s[patlen + 1])) {
 532                         return true;
 533                 }
 534         }
 535         return false;
 536 }