usr.bin/patch/util.c

   1 /*
   2  * $OpenBSD: util.c,v 1.32 2006/03/11 19:41:30 otto Exp $
   3  * $DragonFly: src/usr.bin/patch/util.c,v 1.9 2007/09/29 23:11:10 swildner Exp $
   4  * $NetBSD$
   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 __RCSID("$NetBSD$");
  35
  36 #include <sys/param.h>
  37 #include <sys/stat.h>
  38
  39 #include <ctype.h>
  40 #include <errno.h>
  41 #include <fcntl.h>
  42 #include <libgen.h>
  43 #include <paths.h>
  44 #include <signal.h>
  45 #include <stdarg.h>
  46 #include <stdlib.h>
  47 #include <stdio.h>
  48 #include <string.h>
  49 #include <unistd.h>
  50
  51 #include "common.h"
  52 #include "util.h"
  53 #include "backupfile.h"
  54 #include "pathnames.h"
  55
  56 /* Rename a file, copying it if necessary. */
  57
  58 int
  59 move_file(const char *from, const char *to)
  60 {
  61         int     fromfd;
  62         ssize_t i;
  63
  64         /* to stdout? */
  65
  66         if (strEQ(to, "-")) {
  67 #ifdef DEBUGGING
  68                 if (debug & 4)
  69                         say("Moving %s to stdout.\n", from);
  70 #endif
  71                 fromfd = open(from, O_RDONLY);
  72                 if (fromfd < 0)
  73                         pfatal("internal error, can't reopen %s", from);
  74                 while ((i = read(fromfd, buf, buf_len)) > 0)
  75                         if (write(STDOUT_FILENO, buf, i) != i)
  76                                 pfatal("write failed");
  77                 close(fromfd);
  78                 return 0;
  79         }
  80         if (backup_file(to) < 0) {
  81                 say("Can't backup %s, output is in %s: %s\n", to, from,
  82                     strerror(errno));
  83                 return -1;
  84         }
  85 #ifdef DEBUGGING
  86         if (debug & 4)
  87                 say("Moving %s to %s.\n", from, to);
  88 #endif
  89         if (rename(from, to) < 0) {
  90                 if (errno != EXDEV || copy_file(from, to) < 0) {
  91                         say("Can't create %s, output is in %s: %s\n",
  92                             to, from, strerror(errno));
  93                         return -1;
  94                 }
  95         }
  96         return 0;
  97 }
  98
  99 /* Backup the original file.  */
 100
 101 int
 102 backup_file(const char *orig)
 103 {
 104         struct stat     filestat;
 105         char            bakname[MAXPATHLEN], *s, *simplename;
 106         dev_t           orig_device;
 107         ino_t           orig_inode;
 108
 109         if (backup_type == none || stat(orig, &filestat) != 0)
 110                 return 0;                       /* nothing to do */
 111         /*
 112          * If the user used zero prefixes or suffixes, then
 113          * he doesn't want backups.  Yet we have to remove
 114          * orig to break possible hardlinks.
 115          */
 116         if ((origprae && *origprae == 0) || *simple_backup_suffix == 0) {
 117                 unlink(orig);
 118                 return 0;
 119         }
 120         orig_device = filestat.st_dev;
 121         orig_inode = filestat.st_ino;
 122
 123         if (origprae) {
 124                 if (strlcpy(bakname, origprae, sizeof(bakname)) >= sizeof(bakname) ||
 125                     strlcat(bakname, orig, sizeof(bakname)) >= sizeof(bakname))
 126                         fatal("filename %s too long for buffer\n", origprae);
 127         } else {
 128                 if ((s = find_backup_file_name(orig)) == NULL)
 129                         fatal("out of memory\n");
 130                 if (strlcpy(bakname, s, sizeof(bakname)) >= sizeof(bakname))
 131                         fatal("filename %s too long for buffer\n", s);
 132                 free(s);
 133         }
 134
 135         if ((simplename = strrchr(bakname, '/')) != NULL)
 136                 simplename = simplename + 1;
 137         else
 138                 simplename = bakname;
 139
 140         /*
 141          * Find a backup name that is not the same file. Change the
 142          * first lowercase char into uppercase; if that isn't
 143          * sufficient, chop off the first char and try again.
 144          */
 145         while (stat(bakname, &filestat) == 0 &&
 146             orig_device == filestat.st_dev && orig_inode == filestat.st_ino) {
 147                 /* Skip initial non-lowercase chars.  */
 148                 for (s = simplename; *s && !islower((unsigned char)*s); s++)
 149                         ;
 150                 if (*s)
 151                         *s = toupper((unsigned char)*s);
 152                 else
 153                         memmove(simplename, simplename + 1,
 154                             strlen(simplename + 1) + 1);
 155         }
 156 #ifdef DEBUGGING
 157         if (debug & 4)
 158                 say("Moving %s to %s.\n", orig, bakname);
 159 #endif
 160         if (rename(orig, bakname) < 0) {
 161                 if (errno != EXDEV || copy_file(orig, bakname) < 0)
 162                         return -1;
 163         }
 164         return 0;
 165 }
 166
 167 /*
 168  * Copy a file.
 169  */
 170 int
 171 copy_file(const char *from, const char *to)
 172 {
 173         int     tofd, fromfd;
 174         ssize_t i;
 175
 176         tofd = open(to, O_CREAT|O_TRUNC|O_WRONLY, 0666);
 177         if (tofd < 0)
 178                 return -1;
 179         fromfd = open(from, O_RDONLY, 0);
 180         if (fromfd < 0)
 181                 pfatal("internal error, can't reopen %s", from);
 182         while ((i = read(fromfd, buf, buf_len)) > 0)
 183                 if (write(tofd, buf, i) != i)
 184                         pfatal("write to %s failed", to);
 185         close(fromfd);
 186         close(tofd);
 187         return 0;
 188 }
 189
 190 /*
 191  * Allocate a unique area for a string.
 192  */
 193 char *
 194 savestr(const char *s)
 195 {
 196         char    *rv;
 197
 198         if (!s)
 199                 s = "Oops";
 200         rv = strdup(s);
 201         if (rv == NULL) {
 202                 if (using_plan_a)
 203                         out_of_mem = true;
 204                 else
 205                         fatal("out of memory\n");
 206         }
 207         return rv;
 208 }
 209
 210 /*
 211  * Vanilla terminal output (buffered).
 212  */
 213 void
 214 say(const char *fmt, ...)
 215 {
 216         va_list ap;
 217
 218         va_start(ap, fmt);
 219         vfprintf(stderr, fmt, ap);
 220         va_end(ap);
 221         fflush(stderr);
 222 }
 223
 224 /*
 225  * Terminal output, pun intended.
 226  */
 227 void
 228 fatal(const char *fmt, ...)
 229 {
 230         va_list ap;
 231
 232         va_start(ap, fmt);
 233         fprintf(stderr, "patch: **** ");
 234         vfprintf(stderr, fmt, ap);
 235         va_end(ap);
 236         my_exit(2);
 237 }
 238
 239 /*
 240  * Say something from patch, something from the system, then silence . . .
 241  */
 242 void
 243 pfatal(const char *fmt, ...)
 244 {
 245         va_list ap;
 246         int     errnum = errno;
 247
 248         fprintf(stderr, "patch: **** ");
 249         va_start(ap, fmt);
 250         vfprintf(stderr, fmt, ap);
 251         va_end(ap);
 252         fprintf(stderr, ": %s\n", strerror(errnum));
 253         my_exit(2);
 254 }
 255
 256 /*
 257  * Get a response from the user via /dev/tty
 258  */
 259 void
 260 ask(const char *fmt, ...)
 261 {
 262         va_list ap;
 263         ssize_t nr = 0;
 264         static  int ttyfd = -1;
 265
 266         va_start(ap, fmt);
 267         vfprintf(stdout, fmt, ap);
 268         va_end(ap);
 269         fflush(stdout);
 270         if (ttyfd < 0)
 271                 ttyfd = open(_PATH_TTY, O_RDONLY);
 272         if (ttyfd >= 0) {
 273                 if ((nr = read(ttyfd, buf, buf_len)) > 0 &&
 274                     buf[nr - 1] == '\n')
 275                         buf[nr - 1] = '\0';
 276         }
 277         if (ttyfd < 0 || nr <= 0) {
 278                 /* no tty or error reading, pretend user entered 'return' */
 279                 putchar('\n');
 280                 buf[0] = '\0';
 281         }
 282 }
 283
 284 /*
 285  * How to handle certain events when not in a critical region.
 286  */
 287 void
 288 set_signals(int reset)
 289 {
 290         static sig_t    hupval, intval;
 291
 292         if (!reset) {
 293                 hupval = signal(SIGHUP, SIG_IGN);
 294                 if (hupval != SIG_IGN)
 295                         hupval = my_exit;
 296                 intval = signal(SIGINT, SIG_IGN);
 297                 if (intval != SIG_IGN)
 298                         intval = my_exit;
 299         }
 300         signal(SIGHUP, hupval);
 301         signal(SIGINT, intval);
 302 }
 303
 304 /*
 305  * How to handle certain events when in a critical region.
 306  */
 307 void
 308 ignore_signals(void)
 309 {
 310         signal(SIGHUP, SIG_IGN);
 311         signal(SIGINT, SIG_IGN);
 312 }
 313
 314 /*
 315  * Make sure we'll have the directories to create a file. If `striplast' is
 316  * true, ignore the last element of `filename'.
 317  */
 318
 319 void
 320 makedirs(const char *filename, bool striplast)
 321 {
 322         char    *tmpbuf;
 323
 324         if ((tmpbuf = strdup(filename)) == NULL)
 325                 fatal("out of memory\n");
 326
 327         if (striplast) {
 328                 char    *s = strrchr(tmpbuf, '/');
 329                 if (s == NULL)
 330                         return; /* nothing to be done */
 331                 *s = '\0';
 332         }
 333         if (mkpath(tmpbuf) != 0)
 334                 pfatal("creation of %s failed", tmpbuf);
 335         free(tmpbuf);
 336 }
 337
 338 /*
 339  * Make filenames more reasonable.
 340  */
 341 char *
 342 fetchname(const char *at, bool *exists, int strip_leading)
 343 {
 344         char            *fullname, *name, *t;
 345         int             sleading, tab;
 346         struct stat     filestat;
 347
 348         if (at == NULL || *at == '\0')
 349                 return NULL;
 350         while (isspace((unsigned char)*at))
 351                 at++;
 352 #ifdef DEBUGGING
 353         if (debug & 128)
 354                 say("fetchname %s %d\n", at, strip_leading);
 355 #endif
 356         /* So files can be created by diffing against /dev/null.  */
 357         if (strnEQ(at, _PATH_DEVNULL, sizeof(_PATH_DEVNULL) - 1))
 358                 return NULL;
 359         name = fullname = t = savestr(at);
 360
 361         tab = strchr(t, '\t') != NULL;
 362         /* Strip off up to `strip_leading' path components and NUL terminate. */
 363         for (sleading = strip_leading; *t != '\0' && ((tab && *t != '\t') ||
 364             !isspace((unsigned char)*t)); t++) {
 365                 if (t[0] == '/' && t[1] != '/' && t[1] != '\0')
 366                         if (--sleading >= 0)
 367                                 name = t + 1;
 368         }
 369         *t = '\0';
 370
 371         /*
 372          * If no -p option was given (957 is the default value!), we were
 373          * given a relative pathname, and the leading directories that we
 374          * just stripped off all exist, put them back on.
 375          */
 376         if (strip_leading == 957 && name != fullname && *fullname != '/') {
 377                 name[-1] = '\0';
 378                 if (stat(fullname, &filestat) == 0 && S_ISDIR(filestat.st_mode)) {
 379                         name[-1] = '/';
 380                         name = fullname;
 381                 }
 382         }
 383         name = savestr(name);
 384         free(fullname);
 385
 386         *exists = stat(name, &filestat) == 0;
 387         return name;
 388 }
 389
 390 /*
 391  * Takes the name returned by fetchname and looks in RCS/SCCS directories
 392  * for a checked in version.
 393  */
 394 char *
 395 checked_in(char *file)
 396 {
 397         char            *filebase, *filedir, tmpbuf[MAXPATHLEN];
 398         struct stat     filestat;
 399
 400         filebase = basename(file);
 401         filedir = dirname(file);
 402
 403 #define try(f, a1, a2, a3) \
 404 (snprintf(tmpbuf, sizeof tmpbuf, f, a1, a2, a3), stat(tmpbuf, &filestat) == 0)
 405
 406         if (try("%s/RCS/%s%s", filedir, filebase, RCSSUFFIX) ||
 407             try("%s/RCS/%s%s", filedir, filebase, "") ||
 408             try("%s/%s%s", filedir, filebase, RCSSUFFIX) ||
 409             try("%s/SCCS/%s%s", filedir, SCCSPREFIX, filebase) ||
 410             try("%s/%s%s", filedir, SCCSPREFIX, filebase))
 411                 return file;
 412
 413         return NULL;
 414 }
 415
 416 void
 417 version(void)
 418 {
 419         fprintf(stderr, "Patch version 2.0-12u8-NetBSD\n");
 420         my_exit(EXIT_SUCCESS);
 421 }
 422
 423 /*
 424  * Exit with cleanup.
 425  */
 426 void
 427 my_exit(int status)
 428 {
 429         unlink(TMPINNAME);
 430         if (!toutkeep)
 431                 unlink(TMPOUTNAME);
 432         if (!trejkeep)
 433                 unlink(TMPREJNAME);
 434         unlink(TMPPATNAME);
 435         exit(status);
 436 }