libbb/copy_file.c

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