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