libbb/copy_file.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * Mini copy_file implementation for busybox
   4  *
   5  * Copyright (C) 2001 by Matt Kraai <kraai@alumni.carnegiemellon.edu>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  15  * General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
  20  *
  21  */
  22
  23 #include <sys/types.h>
  24 #include <sys/stat.h>
  25 #include <unistd.h>
  26 #include <fcntl.h>
  27 #include <utime.h>
  28 #include <errno.h>
  29 #include <dirent.h>
  30 #include <stdlib.h>
  31 #include <string.h>
  32
  33 #include "busybox.h"
  34
  35 int copy_file(const char *source, const char *dest, int flags)
  36 {
  37         struct stat source_stat;
  38         struct stat dest_stat;
  39         int dest_exists = 0;
  40         int status = 0;
  41
  42         if ((!(flags & FILEUTILS_DEREFERENCE) &&
  43                         lstat(source, &source_stat) < 0) ||
  44                         ((flags & FILEUTILS_DEREFERENCE) &&
  45                          stat(source, &source_stat) < 0)) {
  46                 bb_perror_msg("%s", source);
  47                 return -1;
  48         }
  49
  50         if (lstat(dest, &dest_stat) < 0) {
  51                 if (errno != ENOENT) {
  52                         bb_perror_msg("unable to stat `%s'", dest);
  53                         return -1;
  54                 }
  55         } else {
  56                 if (source_stat.st_dev == dest_stat.st_dev &&
  57                         source_stat.st_ino == dest_stat.st_ino) {
  58                 bb_error_msg("`%s' and `%s' are the same file", source, dest);
  59                 return -1;
  60         }
  61                 dest_exists = 1;
  62         }
  63
  64         if (S_ISDIR(source_stat.st_mode)) {
  65                 DIR *dp;
  66                 struct dirent *d;
  67                 mode_t saved_umask = 0;
  68                 char *dstparent;
  69                 struct stat dstparent_stat;
  70
  71                 if (!(flags & FILEUTILS_RECUR)) {
  72                         bb_error_msg("%s: omitting directory", source);
  73                         return -1;
  74                 }
  75
  76                 dstparent = dirname(bb_xstrdup(dest));
  77                 if (lstat(dstparent, &dstparent_stat) < 0) {
  78                         bb_perror_msg("unable to stat `%s'", dstparent);
  79                         free(dstparent);
  80                         return -1;
  81                 }
  82                 free(dstparent);
  83
  84                 if (source_stat.st_dev == dstparent_stat.st_dev &&
  85                         source_stat.st_ino == dstparent_stat.st_ino) {
  86                         bb_error_msg("cannot copy a directory, `%s', into itself, `%s'", source, dest);
  87                         return -1;
  88                 }
  89
  90                 /* Create DEST.  */
  91                 if (dest_exists) {
  92                         if (!S_ISDIR(dest_stat.st_mode)) {
  93                                 bb_error_msg("`%s' is not a directory", dest);
  94                                 return -1;
  95                         }
  96                 } else {
  97                         mode_t mode;
  98                         saved_umask = umask(0);
  99
 100                         mode = source_stat.st_mode;
 101                         if (!(flags & FILEUTILS_PRESERVE_STATUS))
 102                                 mode = source_stat.st_mode & ~saved_umask;
 103                         mode |= S_IRWXU;
 104
 105                         if (mkdir(dest, mode) < 0) {
 106                                 umask(saved_umask);
 107                                 bb_perror_msg("cannot create directory `%s'", dest);
 108                                 return -1;
 109                         }
 110
 111                         umask(saved_umask);
 112                 }
 113
 114                 /* Recursively copy files in SOURCE.  */
 115                 if ((dp = opendir(source)) == NULL) {
 116                         bb_perror_msg("unable to open directory `%s'", source);
 117                         status = -1;
 118                         goto end;
 119                 }
 120
 121                 while ((d = readdir(dp)) != NULL) {
 122                         char *new_source, *new_dest;
 123
 124                         new_source = concat_subpath_file(source, d->d_name);
 125                         if(new_source == NULL)
 126                                 continue;
 127                         new_dest = concat_path_file(dest, d->d_name);
 128                         if (copy_file(new_source, new_dest, flags) < 0)
 129                                 status = -1;
 130                         free(new_source);
 131                         free(new_dest);
 132                 }
 133                 /* closedir have only EBADF error, but "dp" not changes */
 134                 closedir(dp);
 135
 136                 if (!dest_exists &&
 137                                 chmod(dest, source_stat.st_mode & ~saved_umask) < 0) {
 138                         bb_perror_msg("unable to change permissions of `%s'", dest);
 139                         status = -1;
 140                 }
 141         } else if (S_ISREG(source_stat.st_mode)) {
 142                 int src_fd;
 143                 int dst_fd;
 144 #ifdef CONFIG_FEATURE_PRESERVE_HARDLINKS
 145                 char *link_name;
 146
 147                 if (!(flags & FILEUTILS_DEREFERENCE) &&
 148                                 is_in_ino_dev_hashtable(&source_stat, &link_name)) {
 149                         if (link(link_name, dest) < 0) {
 150                                 bb_perror_msg("unable to link `%s'", dest);
 151                                 return -1;
 152                         }
 153
 154                         return 0;
 155                 }
 156 #endif
 157                 src_fd = open(source, O_RDONLY);
 158                 if (src_fd == -1) {
 159                         bb_perror_msg("unable to open `%s'", source);
 160                         return(-1);
 161                 }
 162
 163                 if (dest_exists) {
 164                         if (flags & FILEUTILS_INTERACTIVE) {
 165                                 bb_error_msg("overwrite `%s'? ", dest);
 166                                 if (!bb_ask_confirmation()) {
 167                                         close (src_fd);
 168                                         return 0;
 169                                 }
 170                         }
 171
 172                         dst_fd = open(dest, O_WRONLY|O_TRUNC);
 173                         if (dst_fd == -1) {
 174                                 if (!(flags & FILEUTILS_FORCE)) {
 175                                         bb_perror_msg("unable to open `%s'", dest);
 176                                         close(src_fd);
 177                                         return -1;
 178                                 }
 179
 180                                 if (unlink(dest) < 0) {
 181                                         bb_perror_msg("unable to remove `%s'", dest);
 182                                         close(src_fd);
 183                                         return -1;
 184                                 }
 185
 186                                 dest_exists = 0;
 187                         }
 188                 }
 189
 190                 if (!dest_exists) {
 191                         dst_fd = open(dest, O_WRONLY|O_CREAT, source_stat.st_mode);
 192                         if (dst_fd == -1) {
 193                                 bb_perror_msg("unable to open `%s'", dest);
 194                                 close(src_fd);
 195                                 return(-1);
 196                         }
 197                 }
 198
 199                 if (bb_copyfd_eof(src_fd, dst_fd) == -1)
 200                         status = -1;
 201
 202                 if (close(dst_fd) < 0) {
 203                         bb_perror_msg("unable to close `%s'", dest);
 204                         status = -1;
 205                 }
 206
 207                 if (close(src_fd) < 0) {
 208                         bb_perror_msg("unable to close `%s'", source);
 209                         status = -1;
 210                 }
 211                         }
 212         else if (S_ISBLK(source_stat.st_mode) || S_ISCHR(source_stat.st_mode) ||
 213             S_ISSOCK(source_stat.st_mode) || S_ISFIFO(source_stat.st_mode) ||
 214             S_ISLNK(source_stat.st_mode)) {
 215
 216                 if (dest_exists &&
 217                        ((flags & FILEUTILS_FORCE) == 0 || unlink(dest) < 0)) {
 218                                 bb_perror_msg("unable to remove `%s'", dest);
 219                                 return -1;
 220
 221                         }
 222         } else {
 223                 bb_error_msg("internal error: unrecognized file type");
 224                 return -1;
 225                 }
 226         if (S_ISBLK(source_stat.st_mode) || S_ISCHR(source_stat.st_mode) ||
 227             S_ISSOCK(source_stat.st_mode)) {
 228                 if (mknod(dest, source_stat.st_mode, source_stat.st_rdev) < 0) {
 229                         bb_perror_msg("unable to create `%s'", dest);
 230                         return -1;
 231                 }
 232         } else if (S_ISFIFO(source_stat.st_mode)) {
 233                 if (mkfifo(dest, source_stat.st_mode) < 0) {
 234                         bb_perror_msg("cannot create fifo `%s'", dest);
 235                         return -1;
 236                 }
 237         } else if (S_ISLNK(source_stat.st_mode)) {
 238                 char *lpath;
 239
 240                 lpath = xreadlink(source);
 241                 if (symlink(lpath, dest) < 0) {
 242                         bb_perror_msg("cannot create symlink `%s'", dest);
 243                         return -1;
 244                 }
 245                 free(lpath);
 246
 247 #if (__GLIBC__ >= 2) && (__GLIBC_MINOR__ >= 1)
 248                 if (flags & FILEUTILS_PRESERVE_STATUS)
 249                         if (lchown(dest, source_stat.st_uid, source_stat.st_gid) < 0)
 250                                 bb_perror_msg("unable to preserve ownership of `%s'", dest);
 251 #endif
 252
 253 #ifdef CONFIG_FEATURE_PRESERVE_HARDLINKS
 254                 add_to_ino_dev_hashtable(&source_stat, dest);
 255 #endif
 256
 257                 return 0;
 258         }
 259
 260 #ifdef CONFIG_FEATURE_PRESERVE_HARDLINKS
 261         add_to_ino_dev_hashtable(&source_stat, dest);
 262 #endif
 263
 264 end:
 265
 266         if (flags & FILEUTILS_PRESERVE_STATUS) {
 267                 struct utimbuf times;
 268
 269                 times.actime = source_stat.st_atime;
 270                 times.modtime = source_stat.st_mtime;
 271                 if (utime(dest, &times) < 0)
 272                         bb_perror_msg("unable to preserve times of `%s'", dest);
 273                 if (chown(dest, source_stat.st_uid, source_stat.st_gid) < 0) {
 274                         source_stat.st_mode &= ~(S_ISUID | S_ISGID);
 275                         bb_perror_msg("unable to preserve ownership of `%s'", dest);
 276                 }
 277                 if (chmod(dest, source_stat.st_mode) < 0)
 278                         bb_perror_msg("unable to preserve permissions of `%s'", dest);
 279         }
 280
 281         return status;
 282 }