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 #include <string.h>
  33
  34 #include "libbb.h"
  35
  36 int copy_file(const char *source, const char *dest, int flags)
  37 {
  38         struct stat source_stat;
  39         struct stat dest_stat;
  40         int dest_exists = 1;
  41         int status = 0;
  42
  43         if (((flags & FILEUTILS_PRESERVE_SYMLINKS) &&
  44              lstat(source, &source_stat) < 0) ||
  45             (!(flags & FILEUTILS_PRESERVE_SYMLINKS) &&
  46              stat(source, &source_stat) < 0)) {
  47                 perror_msg("%s", source);
  48                 return -1;
  49         }
  50
  51         if (stat(dest, &dest_stat) < 0) {
  52                 if (errno != ENOENT) {
  53                         perror_msg("unable to stat `%s'", dest);
  54                         return -1;
  55                 }
  56                 dest_exists = 0;
  57         }
  58
  59         if (dest_exists && source_stat.st_rdev == dest_stat.st_rdev &&
  60             source_stat.st_ino == dest_stat.st_ino) {
  61                 error_msg("`%s' and `%s' are the same file", source, dest);
  62                 return -1;
  63         }
  64
  65         if (S_ISDIR(source_stat.st_mode)) {
  66                 DIR *dp;
  67                 struct dirent *d;
  68                 mode_t saved_umask = 0;
  69
  70                 if (!(flags & FILEUTILS_RECUR)) {
  71                         error_msg("%s: omitting directory", source);
  72                         return -1;
  73                 }
  74
  75                 /* Create DEST.  */
  76                 if (dest_exists) {
  77                         if (!S_ISDIR(dest_stat.st_mode)) {
  78                                 error_msg("`%s' is not a directory", dest);
  79                                 return -1;
  80                         }
  81                 } else {
  82                         mode_t mode;
  83                         saved_umask = umask(0);
  84
  85                         mode = source_stat.st_mode;
  86                         if (!(flags & FILEUTILS_PRESERVE_STATUS))
  87                                 mode = source_stat.st_mode & ~saved_umask;
  88                         mode |= S_IRWXU;
  89
  90                         if (mkdir(dest, mode) < 0) {
  91                                 umask(saved_umask);
  92                                 perror_msg("cannot create directory `%s'",
  93                                            dest);
  94                                 return -1;
  95                         }
  96
  97                         umask(saved_umask);
  98                 }
  99
 100                 /* Recursively copy files in SOURCE.  */
 101                 if ((dp = opendir(source)) == NULL) {
 102                         perror_msg("unable to open directory `%s'", source);
 103                         status = -1;
 104                         goto end;
 105                 }
 106
 107                 while ((d = readdir(dp)) != NULL) {
 108                         char *new_source, *new_dest;
 109
 110                         if (strcmp(d->d_name, ".") == 0 ||
 111                             strcmp(d->d_name, "..") == 0)
 112                                 continue;
 113
 114                         new_source = concat_path_file(source, d->d_name);
 115                         new_dest = concat_path_file(dest, d->d_name);
 116                         if (copy_file(new_source, new_dest, flags) < 0)
 117                                 status = -1;
 118                         free(new_source);
 119                         free(new_dest);
 120                 }
 121
 122                 /* ??? What if an error occurs in readdir?  */
 123
 124                 if (closedir(dp) < 0) {
 125                         perror_msg("unable to close directory `%s'", source);
 126                         status = -1;
 127                 }
 128
 129                 if (!dest_exists &&
 130                     chmod(dest, source_stat.st_mode & ~saved_umask) < 0) {
 131                         perror_msg("unable to change permissions of `%s'",
 132                                    dest);
 133                         status = -1;
 134                 }
 135         } else if (S_ISREG(source_stat.st_mode)) {
 136                 FILE *sfp, *dfp;
 137
 138                 if (dest_exists) {
 139                         if ((dfp = fopen(dest, "w")) == NULL) {
 140                                 if (!(flags & FILEUTILS_FORCE)) {
 141                                         perror_msg("unable to open `%s'", dest);
 142                                         return -1;
 143                                 }
 144
 145                                 if (unlink(dest) < 0) {
 146                                         perror_msg("unable to remove `%s'",
 147                                                    dest);
 148                                         return -1;
 149                                 }
 150
 151                                 dest_exists = 0;
 152                         }
 153                 }
 154
 155                 if (!dest_exists) {
 156                         int fd;
 157
 158                         if ((fd =
 159                              open(dest, O_WRONLY | O_CREAT,
 160                                   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                 if (copy_file_chunk(sfp, dfp, -1) < 0)
 177                         status = -1;
 178
 179                 if (fclose(dfp) < 0) {
 180                         perror_msg("unable to close `%s'", dest);
 181                         status = -1;
 182                 }
 183
 184                 if (fclose(sfp) < 0) {
 185                         perror_msg("unable to close `%s'", source);
 186                         status = -1;
 187                 }
 188         } else if (S_ISBLK(source_stat.st_mode) || S_ISCHR(source_stat.st_mode)
 189                    || S_ISSOCK(source_stat.st_mode)) {
 190                 if (mknod(dest, source_stat.st_mode, source_stat.st_rdev) < 0) {
 191                         perror_msg("unable to create `%s'", dest);
 192                         return -1;
 193                 }
 194         } else if (S_ISFIFO(source_stat.st_mode)) {
 195                 if (mkfifo(dest, source_stat.st_mode) < 0) {
 196                         perror_msg("cannot create fifo `%s'", dest);
 197                         return -1;
 198                 }
 199         } else if (S_ISLNK(source_stat.st_mode)) {
 200                 char *lpath = xreadlink(source);
 201                 if (symlink(lpath, dest) < 0) {
 202                         perror_msg("cannot create symlink `%s'", dest);
 203                         return -1;
 204                 }
 205                 free(lpath);
 206
 207 #if (__GLIBC__ >= 2) && (__GLIBC_MINOR__ >= 1)
 208                 if (flags & FILEUTILS_PRESERVE_STATUS)
 209                         if (lchown(dest, source_stat.st_uid, source_stat.st_gid)
 210                             < 0)
 211                                 perror_msg
 212                                     ("unable to preserve ownership of `%s'",
 213                                      dest);
 214 #endif
 215                 return 0;
 216         } else {
 217                 error_msg("internal error: unrecognized file type");
 218                 return -1;
 219         }
 220
 221 end:
 222
 223         if (flags & FILEUTILS_PRESERVE_STATUS) {
 224                 struct utimbuf times;
 225
 226                 times.actime = source_stat.st_atime;
 227                 times.modtime = source_stat.st_mtime;
 228                 if (utime(dest, &times) < 0)
 229                         perror_msg("unable to preserve times of `%s'", dest);
 230                 if (chown(dest, source_stat.st_uid, source_stat.st_gid) < 0) {
 231                         source_stat.st_mode &= ~(S_ISUID | S_ISGID);
 232                         perror_msg("unable to preserve ownership of `%s'",
 233                                    dest);
 234                 }
 235                 if (chmod(dest, source_stat.st_mode) < 0)
 236                         perror_msg("unable to preserve permissions of `%s'",
 237                                    dest);
 238         }
 239
 240         return status;
 241 }