usr.bin/patch/util.c

   1 /*-
   2  * Copyright 1986, Larry Wall
   3  *
   4  * Redistribution and use in source and binary forms, with or without
   5  * modification, are permitted provided that the following condition is met:
   6  * 1. Redistributions of source code must retain the above copyright notice,
   7  * this condition and the following disclaimer.
   8  *
   9  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
  10  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  11  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  12  * DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR
  13  * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  14  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  15  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
  16  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  17  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  18  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  19  * SUCH DAMAGE.
  20  *
  21  * patch - a program to apply diffs to original files
  22  *
  23  * -C option added in 1998, original code by Marc Espie, based on FreeBSD
  24  * behaviour
  25  *
  26  * $OpenBSD: util.c,v 1.35 2010/07/24 01:10:12 ray Exp $
  27  * $FreeBSD: head/usr.bin/patch/util.c 255894 2013-09-26 18:00:45Z delphij $
  28  */
  29
  30 #include <sys/param.h>
  31 #include <sys/stat.h>
  32
  33 #include <ctype.h>
  34 #include <errno.h>
  35 #include <fcntl.h>
  36 #include <libgen.h>
  37 #include <paths.h>
  38 #include <signal.h>
  39 #include <stdarg.h>
  40 #include <stdlib.h>
  41 #include <stdio.h>
  42 #include <string.h>
  43 #include <unistd.h>
  44
  45 #include "common.h"
  46 #include "util.h"
  47 #include "backupfile.h"
  48 #include "pathnames.h"
  49
  50 /* Rename a file, copying it if necessary. */
  51
  52 int
  53 move_file(const char *from, const char *to)
  54 {
  55         int     fromfd;
  56         ssize_t i;
  57
  58         /* to stdout? */
  59
  60         if (strEQ(to, "-")) {
  61 #ifdef DEBUGGING
  62                 if (debug & 4)
  63                         say("Moving %s to stdout.\n", from);
  64 #endif
  65                 fromfd = open(from, O_RDONLY);
  66                 if (fromfd < 0)
  67                         pfatal("internal error, can't reopen %s", from);
  68                 while ((i = read(fromfd, buf, buf_size)) > 0)
  69                         if (write(STDOUT_FILENO, buf, i) != i)
  70                                 pfatal("write failed");
  71                 close(fromfd);
  72                 return 0;
  73         }
  74         if (backup_file(to) < 0) {
  75                 say("Can't backup %s, output is in %s: %s\n", to, from,
  76                     strerror(errno));
  77                 return -1;
  78         }
  79 #ifdef DEBUGGING
  80         if (debug & 4)
  81                 say("Moving %s to %s.\n", from, to);
  82 #endif
  83         if (rename(from, to) < 0) {
  84                 if (errno != EXDEV || copy_file(from, to) < 0) {
  85                         say("Can't create %s, output is in %s: %s\n",
  86                             to, from, strerror(errno));
  87                         return -1;
  88                 }
  89         }
  90         return 0;
  91 }
  92
  93 /* Backup the original file.  */
  94
  95 int
  96 backup_file(const char *orig)
  97 {
  98         struct stat     filestat;
  99         char            bakname[MAXPATHLEN], *s, *simplename;
 100         dev_t           orig_device;
 101         ino_t           orig_inode;
 102
 103         if (backup_type == none || stat(orig, &filestat) != 0)
 104                 return 0;                       /* nothing to do */
 105         /*
 106          * If the user used zero prefixes or suffixes, then
 107          * he doesn't want backups.  Yet we have to remove
 108          * orig to break possible hardlinks.
 109          */
 110         if ((origprae && *origprae == 0) || *simple_backup_suffix == 0) {
 111                 unlink(orig);
 112                 return 0;
 113         }
 114         orig_device = filestat.st_dev;
 115         orig_inode = filestat.st_ino;
 116
 117         if (origprae) {
 118                 if (strlcpy(bakname, origprae, sizeof(bakname)) >= sizeof(bakname) ||
 119                     strlcat(bakname, orig, sizeof(bakname)) >= sizeof(bakname))
 120                         fatal("filename %s too long for buffer\n", origprae);
 121         } else {
 122                 if ((s = find_backup_file_name(orig)) == NULL)
 123                         fatal("out of memory\n");
 124                 if (strlcpy(bakname, s, sizeof(bakname)) >= sizeof(bakname))
 125                         fatal("filename %s too long for buffer\n", s);
 126                 free(s);
 127         }
 128
 129         if ((simplename = strrchr(bakname, '/')) != NULL)
 130                 simplename = simplename + 1;
 131         else
 132                 simplename = bakname;
 133
 134         /*
 135          * Find a backup name that is not the same file. Change the
 136          * first lowercase char into uppercase; if that isn't
 137          * sufficient, chop off the first char and try again.
 138          */
 139         while (stat(bakname, &filestat) == 0 &&
 140             orig_device == filestat.st_dev && orig_inode == filestat.st_ino) {
 141                 /* Skip initial non-lowercase chars.  */
 142                 for (s = simplename; *s && !islower((unsigned char)*s); s++)
 143                         ;
 144                 if (*s)
 145                         *s = toupper((unsigned char)*s);
 146                 else
 147                         memmove(simplename, simplename + 1,
 148                             strlen(simplename + 1) + 1);
 149         }
 150 #ifdef DEBUGGING
 151         if (debug & 4)
 152                 say("Moving %s to %s.\n", orig, bakname);
 153 #endif
 154         if (rename(orig, bakname) < 0) {
 155                 if (errno != EXDEV || copy_file(orig, bakname) < 0)
 156                         return -1;
 157         }
 158         return 0;
 159 }
 160
 161 /*
 162  * Copy a file.
 163  */
 164 int
 165 copy_file(const char *from, const char *to)
 166 {
 167         int     tofd, fromfd;
 168         ssize_t i;
 169
 170         tofd = open(to, O_CREAT|O_TRUNC|O_WRONLY, 0666);
 171         if (tofd < 0)
 172                 return -1;
 173         fromfd = open(from, O_RDONLY, 0);
 174         if (fromfd < 0)
 175                 pfatal("internal error, can't reopen %s", from);
 176         while ((i = read(fromfd, buf, buf_size)) > 0)
 177                 if (write(tofd, buf, i) != i)
 178                         pfatal("write to %s failed", to);
 179         close(fromfd);
 180         close(tofd);
 181         return 0;
 182 }
 183
 184 /*
 185  * Allocate a unique area for a string.
 186  */
 187 char *
 188 savestr(const char *s)
 189 {
 190         char    *rv;
 191
 192         if (!s)
 193                 s = "Oops";
 194         rv = strdup(s);
 195         if (rv == NULL) {
 196                 if (using_plan_a)
 197                         out_of_mem = true;
 198                 else
 199                         fatal("out of memory\n");
 200         }
 201         return rv;
 202 }
 203
 204 /*
 205  * Vanilla terminal output (buffered).
 206  */
 207 void
 208 say(const char *fmt, ...)
 209 {
 210         va_list ap;
 211
 212         va_start(ap, fmt);
 213         vfprintf(stdout, fmt, ap);
 214         va_end(ap);
 215         fflush(stdout);
 216 }
 217
 218 /*
 219  * Terminal output, pun intended.
 220  */
 221 void
 222 fatal(const char *fmt, ...)
 223 {
 224         va_list ap;
 225
 226         va_start(ap, fmt);
 227         fprintf(stderr, "patch: **** ");
 228         vfprintf(stderr, fmt, ap);
 229         va_end(ap);
 230         my_exit(2);
 231 }
 232
 233 /*
 234  * Say something from patch, something from the system, then silence . . .
 235  */
 236 void
 237 pfatal(const char *fmt, ...)
 238 {
 239         va_list ap;
 240         int     errnum = errno;
 241
 242         fprintf(stderr, "patch: **** ");
 243         va_start(ap, fmt);
 244         vfprintf(stderr, fmt, ap);
 245         va_end(ap);
 246         fprintf(stderr, ": %s\n", strerror(errnum));
 247         my_exit(2);
 248 }
 249
 250 /*
 251  * Get a response from the user via /dev/tty
 252  */
 253 void
 254 ask(const char *fmt, ...)
 255 {
 256         va_list ap;
 257         ssize_t nr = 0;
 258         static  int ttyfd = -1;
 259
 260         va_start(ap, fmt);
 261         vfprintf(stdout, fmt, ap);
 262         va_end(ap);
 263         fflush(stdout);
 264         if (ttyfd < 0)
 265                 ttyfd = open(_PATH_TTY, O_RDONLY);
 266         if (ttyfd >= 0) {
 267                 if ((nr = read(ttyfd, buf, buf_size)) > 0 &&
 268                     buf[nr - 1] == '\n')
 269                         buf[nr - 1] = '\0';
 270         }
 271         if (ttyfd < 0 || nr <= 0) {
 272                 /* no tty or error reading, pretend user entered 'return' */
 273                 putchar('\n');
 274                 buf[0] = '\0';
 275         }
 276 }
 277
 278 /*
 279  * How to handle certain events when not in a critical region.
 280  */
 281 void
 282 set_signals(int reset)
 283 {
 284         static sig_t    hupval, intval;
 285
 286         if (!reset) {
 287                 hupval = signal(SIGHUP, SIG_IGN);
 288                 if (hupval != SIG_IGN)
 289                         hupval = my_exit;
 290                 intval = signal(SIGINT, SIG_IGN);
 291                 if (intval != SIG_IGN)
 292                         intval = my_exit;
 293         }
 294         signal(SIGHUP, hupval);
 295         signal(SIGINT, intval);
 296 }
 297
 298 /*
 299  * How to handle certain events when in a critical region.
 300  */
 301 void
 302 ignore_signals(void)
 303 {
 304         signal(SIGHUP, SIG_IGN);
 305         signal(SIGINT, SIG_IGN);
 306 }
 307
 308 /*
 309  * Make sure we'll have the directories to create a file. If `striplast' is
 310  * true, ignore the last element of `filename'.
 311  */
 312
 313 void
 314 makedirs(const char *filename, bool striplast)
 315 {
 316         char    *tmpbuf;
 317
 318         if ((tmpbuf = strdup(filename)) == NULL)
 319                 fatal("out of memory\n");
 320
 321         if (striplast) {
 322                 char    *s = strrchr(tmpbuf, '/');
 323                 if (s == NULL) {
 324                         free(tmpbuf);
 325                         return; /* nothing to be done */
 326                 }
 327                 *s = '\0';
 328         }
 329         if (mkpath(tmpbuf) != 0)
 330                 pfatal("creation of %s failed", tmpbuf);
 331         free(tmpbuf);
 332 }
 333
 334 /*
 335  * Make filenames more reasonable.
 336  */
 337 char *
 338 fetchname(const char *at, bool *exists, int strip_leading)
 339 {
 340         char            *fullname, *name, *t;
 341         int             sleading, tab;
 342         struct stat     filestat;
 343
 344         if (at == NULL || *at == '\0')
 345                 return NULL;
 346         while (isspace((unsigned char)*at))
 347                 at++;
 348 #ifdef DEBUGGING
 349         if (debug & 128)
 350                 say("fetchname %s %d\n", at, strip_leading);
 351 #endif
 352         /* So files can be created by diffing against /dev/null.  */
 353         if (strnEQ(at, _PATH_DEVNULL, sizeof(_PATH_DEVNULL) - 1))
 354                 return NULL;
 355         name = fullname = t = savestr(at);
 356
 357         tab = strchr(t, '\t') != NULL;
 358         /* Strip off up to `strip_leading' path components and NUL terminate. */
 359         for (sleading = strip_leading; *t != '\0' && ((tab && *t != '\t') ||
 360             !isspace((unsigned char)*t)); t++) {
 361                 if (t[0] == '/' && t[1] != '/' && t[1] != '\0')
 362                         if (--sleading >= 0)
 363                                 name = t + 1;
 364         }
 365         *t = '\0';
 366
 367         /*
 368          * If no -p option was given (957 is the default value!), we were
 369          * given a relative pathname, and the leading directories that we
 370          * just stripped off all exist, put them back on.
 371          */
 372         if (strip_leading == 957 && name != fullname && *fullname != '/') {
 373                 name[-1] = '\0';
 374                 if (stat(fullname, &filestat) == 0 && S_ISDIR(filestat.st_mode)) {
 375                         name[-1] = '/';
 376                         name = fullname;
 377                 }
 378         }
 379         name = savestr(name);
 380         free(fullname);
 381
 382         *exists = stat(name, &filestat) == 0;
 383         return name;
 384 }
 385
 386 /*
 387  * Takes the name returned by fetchname and looks in RCS/SCCS directories
 388  * for a checked in version.
 389  */
 390 char *
 391 checked_in(char *file)
 392 {
 393         char            *filebase, *filedir, tmpbuf[MAXPATHLEN];
 394         struct stat     filestat;
 395
 396         filebase = basename(file);
 397         filedir = dirname(file);
 398
 399 #define try(f, a1, a2, a3) \
 400 (snprintf(tmpbuf, sizeof tmpbuf, f, a1, a2, a3), stat(tmpbuf, &filestat) == 0)
 401
 402         if (try("%s/RCS/%s%s", filedir, filebase, RCSSUFFIX) ||
 403             try("%s/RCS/%s%s", filedir, filebase, "") ||
 404             try("%s/%s%s", filedir, filebase, RCSSUFFIX) ||
 405             try("%s/SCCS/%s%s", filedir, SCCSPREFIX, filebase) ||
 406             try("%s/%s%s", filedir, SCCSPREFIX, filebase))
 407                 return file;
 408
 409         return NULL;
 410 }
 411
 412 void
 413 version(void)
 414 {
 415         fprintf(stderr, "patch 2.0-12u10\n");
 416         my_exit(EXIT_SUCCESS);
 417 }
 418
 419 /*
 420  * Exit with cleanup.
 421  */
 422 void
 423 my_exit(int status)
 424 {
 425         unlink(TMPINNAME);
 426         if (!toutkeep)
 427                 unlink(TMPOUTNAME);
 428         if (!trejkeep)
 429                 unlink(TMPREJNAME);
 430         unlink(TMPPATNAME);
 431         exit(status);
 432 }