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  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
   8  *
   9  */
  10
  11 #include <sys/types.h>
  12 #include <sys/stat.h>
  13 #include <unistd.h>
  14 #include <fcntl.h>
  15 #include <utime.h>
  16 #include <errno.h>
  17 #include <dirent.h>
  18 #include <stdlib.h>
  19 #include <string.h>
  20
  21 #include "busybox.h"
  22
  23 /* Compiler version-specific crap that should be in a header file somewhere. */
  24
  25 #if !((__GLIBC__ >= 2) && (__GLIBC_MINOR__ >= 1))
  26 #define lchown chown
  27 #endif
  28
  29
  30 int copy_file(const char *source, const char *dest, int flags)
  31 {
  32         struct stat source_stat;
  33         struct stat dest_stat;
  34         int dest_exists = 0;
  35         int status = 0;
  36
  37         if ((!(flags & FILEUTILS_DEREFERENCE) &&
  38                         lstat(source, &source_stat) < 0) ||
  39                         ((flags & FILEUTILS_DEREFERENCE) &&
  40                          stat(source, &source_stat) < 0)) {
  41                 bb_perror_msg("%s", source);
  42                 return -1;
  43         }
  44
  45         if (lstat(dest, &dest_stat) < 0) {
  46                 if (errno != ENOENT) {
  47                         bb_perror_msg("unable to stat `%s'", dest);
  48                         return -1;
  49                 }
  50         } else {
  51                 if (source_stat.st_dev == dest_stat.st_dev &&
  52                         source_stat.st_ino == dest_stat.st_ino)
  53                 {
  54                         bb_error_msg("`%s' and `%s' are the same file", source, dest);
  55                         return -1;
  56                 }
  57                 dest_exists = 1;
  58         }
  59
  60         if (S_ISDIR(source_stat.st_mode)) {
  61                 DIR *dp;
  62                 struct dirent *d;
  63                 mode_t saved_umask = 0;
  64
  65                 if (!(flags & FILEUTILS_RECUR)) {
  66                         bb_error_msg("%s: omitting directory", source);
  67                         return -1;
  68                 }
  69
  70                 /* Create DEST.  */
  71                 if (dest_exists) {
  72                         if (!S_ISDIR(dest_stat.st_mode)) {
  73                                 bb_error_msg("`%s' is not a directory", dest);
  74                                 return -1;
  75                         }
  76                 } else {
  77                         mode_t mode;
  78                         saved_umask = umask(0);
  79
  80                         mode = source_stat.st_mode;
  81                         if (!(flags & FILEUTILS_PRESERVE_STATUS))
  82                                 mode = source_stat.st_mode & ~saved_umask;
  83                         mode |= S_IRWXU;
  84
  85                         if (mkdir(dest, mode) < 0) {
  86                                 umask(saved_umask);
  87                                 bb_perror_msg("cannot create directory `%s'", dest);
  88                                 return -1;
  89                         }
  90
  91                         umask(saved_umask);
  92                 }
  93
  94                 /* Recursively copy files in SOURCE.  */
  95                 if ((dp = opendir(source)) == NULL) {
  96                         bb_perror_msg("unable to open directory `%s'", source);
  97                         status = -1;
  98                         goto preserve_status;
  99                 }
 100
 101                 while ((d = readdir(dp)) != NULL) {
 102                         char *new_source, *new_dest;
 103
 104                         new_source = concat_subpath_file(source, d->d_name);
 105                         if(new_source == NULL)
 106                                 continue;
 107                         new_dest = concat_path_file(dest, d->d_name);
 108                         if (copy_file(new_source, new_dest, flags) < 0)
 109                                 status = -1;
 110                         free(new_source);
 111                         free(new_dest);
 112                 }
 113                 /* closedir have only EBADF error, but "dp" not changes */
 114                 closedir(dp);
 115
 116                 if (!dest_exists &&
 117                                 chmod(dest, source_stat.st_mode & ~saved_umask) < 0) {
 118                         bb_perror_msg("unable to change permissions of `%s'", dest);
 119                         status = -1;
 120                 }
 121         } else if (S_ISREG(source_stat.st_mode) || (flags & FILEUTILS_DEREFERENCE))
 122         {
 123                 int src_fd;
 124                 int dst_fd;
 125 #ifdef CONFIG_FEATURE_PRESERVE_HARDLINKS
 126                 char *link_name;
 127
 128                 if (!(flags & FILEUTILS_DEREFERENCE) &&
 129                                 is_in_ino_dev_hashtable(&source_stat, &link_name)) {
 130                         if (link(link_name, dest) < 0) {
 131                                 bb_perror_msg("unable to link `%s'", dest);
 132                                 return -1;
 133                         }
 134
 135                         return 0;
 136                 }
 137                 add_to_ino_dev_hashtable(&source_stat, dest);
 138 #endif
 139                 src_fd = open(source, O_RDONLY);
 140                 if (src_fd == -1) {
 141                         bb_perror_msg("unable to open `%s'", source);
 142                         return(-1);
 143                 }
 144
 145                 if (dest_exists) {
 146                         if (flags & FILEUTILS_INTERACTIVE) {
 147                                 fprintf(stderr, "%s: overwrite `%s'? ", bb_applet_name, dest);
 148                                 if (!bb_ask_confirmation()) {
 149                                         close (src_fd);
 150                                         return 0;
 151                                 }
 152                         }
 153
 154                         dst_fd = open(dest, O_WRONLY|O_TRUNC);
 155                         if (dst_fd == -1) {
 156                                 if (!(flags & FILEUTILS_FORCE)) {
 157                                         bb_perror_msg("unable to open `%s'", dest);
 158                                         close(src_fd);
 159                                         return -1;
 160                                 }
 161
 162                                 if (unlink(dest) < 0) {
 163                                         bb_perror_msg("unable to remove `%s'", dest);
 164                                         close(src_fd);
 165                                         return -1;
 166                                 }
 167
 168                                 dest_exists = 0;
 169                         }
 170                 }
 171
 172                 if (!dest_exists) {
 173                         dst_fd = open(dest, O_WRONLY|O_CREAT, source_stat.st_mode);
 174                         if (dst_fd == -1) {
 175                                 bb_perror_msg("unable to open `%s'", dest);
 176                                 close(src_fd);
 177                                 return(-1);
 178                         }
 179                 }
 180
 181                 if (bb_copyfd_eof(src_fd, dst_fd) == -1)
 182                         status = -1;
 183
 184                 if (close(dst_fd) < 0) {
 185                         bb_perror_msg("unable to close `%s'", dest);
 186                         status = -1;
 187                 }
 188
 189                 if (close(src_fd) < 0) {
 190                         bb_perror_msg("unable to close `%s'", source);
 191                         status = -1;
 192                 }
 193         } else if (S_ISBLK(source_stat.st_mode) || S_ISCHR(source_stat.st_mode) ||
 194             S_ISSOCK(source_stat.st_mode) || S_ISFIFO(source_stat.st_mode) ||
 195             S_ISLNK(source_stat.st_mode)) {
 196
 197                 if (dest_exists) {
 198                         if((flags & FILEUTILS_FORCE) == 0) {
 199                                 fprintf(stderr, "`%s' exists\n", dest);
 200                                 return -1;
 201                         }
 202                         if(unlink(dest) < 0) {
 203                                 bb_perror_msg("unable to remove `%s'", dest);
 204                                 return -1;
 205                         }
 206                 }
 207                 if (S_ISFIFO(source_stat.st_mode)) {
 208                         if (mkfifo(dest, source_stat.st_mode) < 0) {
 209                                 bb_perror_msg("cannot create fifo `%s'", dest);
 210                                 return -1;
 211                         }
 212                 } else if (S_ISLNK(source_stat.st_mode)) {
 213                         char *lpath;
 214
 215                         lpath = xreadlink(source);
 216                         if (symlink(lpath, dest) < 0) {
 217                                 bb_perror_msg("cannot create symlink `%s'", dest);
 218                                 return -1;
 219                         }
 220                         free(lpath);
 221
 222                         if (flags & FILEUTILS_PRESERVE_STATUS)
 223                                 if (lchown(dest, source_stat.st_uid, source_stat.st_gid) < 0)
 224                                         bb_perror_msg("unable to preserve ownership of `%s'", dest);
 225
 226                         return 0;
 227
 228                 } else {
 229                         if (mknod(dest, source_stat.st_mode, source_stat.st_rdev) < 0) {
 230                                 bb_perror_msg("unable to create `%s'", dest);
 231                                 return -1;
 232                         }
 233                 }
 234         } else {
 235                 bb_error_msg("internal error: unrecognized file type");
 236                 return -1;
 237         }
 238
 239 preserve_status:
 240
 241         if (flags & FILEUTILS_PRESERVE_STATUS) {
 242                 struct utimbuf times;
 243                 char *msg="unable to preserve %s of `%s'";
 244
 245                 times.actime = source_stat.st_atime;
 246                 times.modtime = source_stat.st_mtime;
 247                 if (utime(dest, &times) < 0)
 248                         bb_perror_msg(msg, "times", dest);
 249                 if (chown(dest, source_stat.st_uid, source_stat.st_gid) < 0) {
 250                         source_stat.st_mode &= ~(S_ISUID | S_ISGID);
 251                         bb_perror_msg(msg, "ownership", dest);
 252                 }
 253                 if (chmod(dest, source_stat.st_mode) < 0)
 254                         bb_perror_msg(msg, "permissions", dest);
 255         }
 256
 257         return status;
 258 }