1 /* core functions for copying files and directories 2 Copyright (C) 1989-2018 Free Software Foundation, Inc. 3 4 This program is free software: you can redistribute it and/or modify 5 it under the terms of the GNU General Public License as published by 6 the Free Software Foundation, either version 3 of the License, or 7 (at your option) any later version. 8 9 This program is distributed in the hope that it will be useful, 10 but WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12 GNU General Public License for more details. 13 14 You should have received a copy of the GNU General Public License 15 along with this program. If not, see <https://www.gnu.org/licenses/>. */ 16 17 /* Extracted from cp.c and librarified by Jim Meyering. */ 18 19 #ifndef COPY_H 20 # define COPY_H 21 22 # include <stdbool.h> 23 # include "hash.h" 24 25 /* Control creation of sparse files (files with holes). */ 26 enum Sparse_type 27 { 28 SPARSE_UNUSED, 29 30 /* Never create holes in DEST. */ 31 SPARSE_NEVER, 32 33 /* This is the default. Use a crude (and sometimes inaccurate) 34 heuristic to determine if SOURCE has holes. If so, try to create 35 holes in DEST. */ 36 SPARSE_AUTO, 37 38 /* For every sufficiently long sequence of bytes in SOURCE, try to 39 create a corresponding hole in DEST. There is a performance penalty 40 here because CP has to search for holes in SRC. But if the holes are 41 big enough, that penalty can be offset by the decrease in the amount 42 of data written to disk. */ 43 SPARSE_ALWAYS 44 }; 45 46 /* Control creation of COW files. */ 47 enum Reflink_type 48 { 49 /* Default to a standard copy. */ 50 REFLINK_NEVER, 51 52 /* Try a COW copy and fall back to a standard copy. */ 53 REFLINK_AUTO, 54 55 /* Require a COW copy and fail if not available. */ 56 REFLINK_ALWAYS 57 }; 58 59 /* This type is used to help mv (via copy.c) distinguish these cases. */ 60 enum Interactive 61 { 62 I_ALWAYS_YES = 1, 63 I_ALWAYS_NO, 64 I_ASK_USER, 65 I_UNSPECIFIED 66 }; 67 68 /* How to handle symbolic links. */ 69 enum Dereference_symlink 70 { 71 DEREF_UNDEFINED = 1, 72 73 /* Copy the symbolic link itself. -P */ 74 DEREF_NEVER, 75 76 /* If the symbolic is a command line argument, then copy 77 its referent. Otherwise, copy the symbolic link itself. -H */ 78 DEREF_COMMAND_LINE_ARGUMENTS, 79 80 /* Copy the referent of the symbolic link. -L */ 81 DEREF_ALWAYS 82 }; 83 84 # define VALID_SPARSE_MODE(Mode) \ 85 ((Mode) == SPARSE_NEVER \ 86 || (Mode) == SPARSE_AUTO \ 87 || (Mode) == SPARSE_ALWAYS) 88 89 # define VALID_REFLINK_MODE(Mode) \ 90 ((Mode) == REFLINK_NEVER \ 91 || (Mode) == REFLINK_AUTO \ 92 || (Mode) == REFLINK_ALWAYS) 93 94 /* These options control how files are copied by at least the 95 following programs: mv (when rename doesn't work), cp, install. 96 So, if you add a new member, be sure to initialize it in 97 mv.c, cp.c, and install.c. */ 98 struct cp_options 99 { 100 enum backup_type backup_type; 101 102 /* How to handle symlinks in the source. */ 103 enum Dereference_symlink dereference; 104 105 /* This value is used to determine whether to prompt before removing 106 each existing destination file. It works differently depending on 107 whether move_mode is set. See code/comments in copy.c. */ 108 enum Interactive interactive; 109 110 /* Control creation of sparse files. */ 111 enum Sparse_type sparse_mode; 112 113 /* Set the mode of the destination file to exactly this value 114 if SET_MODE is nonzero. */ 115 mode_t mode; 116 117 /* If true, copy all files except (directories and, if not dereferencing 118 them, symbolic links,) as if they were regular files. */ 119 bool copy_as_regular; 120 121 /* If true, remove each existing destination nondirectory before 122 trying to open it. */ 123 bool unlink_dest_before_opening; 124 125 /* If true, first try to open each existing destination nondirectory, 126 then, if the open fails, unlink and try again. 127 This option must be set for 'cp -f', in case the destination file 128 exists when the open is attempted. It is irrelevant to 'mv' since 129 any destination is sure to be removed before the open. */ 130 bool unlink_dest_after_failed_open; 131 132 /* If true, create hard links instead of copying files. 133 Create destination directories as usual. */ 134 bool hard_link; 135 136 /* If true, rather than copying, first attempt to use rename. 137 If that fails, then resort to copying. */ 138 bool move_mode; 139 140 /* If true, install(1) is the caller. */ 141 bool install_mode; 142 143 /* Whether this process has appropriate privileges to chown a file 144 whose owner is not the effective user ID. */ 145 bool chown_privileges; 146 147 /* Whether this process has appropriate privileges to do the 148 following operations on a file even when it is owned by some 149 other user: set the file's atime, mtime, mode, or ACL; remove or 150 rename an entry in the file even though it is a sticky directory, 151 or to mount on the file. */ 152 bool owner_privileges; 153 154 /* If true, when copying recursively, skip any subdirectories that are 155 on different file systems from the one we started on. */ 156 bool one_file_system; 157 158 /* If true, attempt to give the copies the original files' permissions, 159 owner, group, and timestamps. */ 160 bool preserve_ownership; 161 bool preserve_mode; 162 bool preserve_timestamps; 163 bool explicit_no_preserve_mode; 164 165 /* If true, attempt to set specified security context */ 166 bool set_security_context; 167 168 /* Enabled for mv, and for cp by the --preserve=links option. 169 If true, attempt to preserve in the destination files any 170 logical hard links between the source files. If used with cp's 171 --no-dereference option, and copying two hard-linked files, 172 the two corresponding destination files will also be hard linked. 173 174 If used with cp's --dereference (-L) option, then, as that option implies, 175 hard links are *not* preserved. However, when copying a file F and 176 a symlink S to F, the resulting S and F in the destination directory 177 will be hard links to the same file (a copy of F). */ 178 bool preserve_links; 179 180 /* Optionally don't copy the data, either with CoW reflink files or 181 explicitly with the --attributes-only option. */ 182 bool data_copy_required; 183 184 /* If true and any of the above (for preserve) file attributes cannot 185 be applied to a destination file, treat it as a failure and return 186 nonzero immediately. E.g. for cp -p this must be true, for mv it 187 must be false. */ 188 bool require_preserve; 189 190 /* If true, attempt to preserve the SELinux security context, too. 191 Set this only if the kernel is SELinux enabled. */ 192 bool preserve_security_context; 193 194 /* Useful only when preserve_context is true. 195 If true, a failed attempt to preserve file's security context 196 propagates failure "out" to the caller, along with full diagnostics. 197 If false, a failure to preserve file's security context does not 198 change the invoking application's exit status, but may output diagnostics. 199 For example, with 'cp --preserve=context' this flag is "true", 200 while with 'cp --preserve=all' or 'cp -a', it is "false". */ 201 bool require_preserve_context; 202 203 /* If true, attempt to preserve extended attributes using libattr. 204 Ignored if coreutils are compiled without xattr support. */ 205 bool preserve_xattr; 206 207 /* Useful only when preserve_xattr is true. 208 If true, a failed attempt to preserve file's extended attributes 209 propagates failure "out" to the caller, along with full diagnostics. 210 If false, a failure to preserve file's extended attributes does not 211 change the invoking application's exit status, but may output diagnostics. 212 For example, with 'cp --preserve=xattr' this flag is "true", 213 while with 'cp --preserve=all' or 'cp -a', it is "false". */ 214 bool require_preserve_xattr; 215 216 /* This allows us to output warnings in cases 2 and 4 below, 217 while being quiet for case 1 (when reduce_diagnostics is true). 218 1. cp -a try to copy xattrs with no errors 219 2. cp --preserve=all copy xattrs with all but ENOTSUP warnings 220 3. cp --preserve=xattr,context copy xattrs with all errors 221 4. mv copy xattrs with all but ENOTSUP warnings 222 */ 223 bool reduce_diagnostics; 224 225 /* If true, copy directories recursively and copy special files 226 as themselves rather than copying their contents. */ 227 bool recursive; 228 229 /* If true, set file mode to value of MODE. Otherwise, 230 set it based on current umask modified by UMASK_KILL. */ 231 bool set_mode; 232 233 /* If true, create symbolic links instead of copying files. 234 Create destination directories as usual. */ 235 bool symbolic_link; 236 237 /* If true, do not copy a nondirectory that has an existing destination 238 with the same or newer modification time. */ 239 bool update; 240 241 /* If true, display the names of the files before copying them. */ 242 bool verbose; 243 244 /* If true, stdin is a tty. */ 245 bool stdin_tty; 246 247 /* If true, open a dangling destination symlink when not in move_mode. 248 Otherwise, copy_reg gives a diagnostic (it refuses to write through 249 such a symlink) and returns false. */ 250 bool open_dangling_dest_symlink; 251 252 /* If true, this is the last filed to be copied. mv uses this to 253 avoid some unnecessary work. */ 254 bool last_file; 255 256 /* Zero if the source has already been renamed to the destination; a 257 positive errno number if this failed with the given errno; -1 if 258 no attempt has been made to rename. Always -1, except for mv. */ 259 int rename_errno; 260 261 /* Control creation of COW files. */ 262 enum Reflink_type reflink_mode; 263 264 /* This is a set of destination name/inode/dev triples. Each such triple 265 represents a file we have created corresponding to a source file name 266 that was specified on the command line. Use it to avoid clobbering 267 source files in commands like this: 268 rm -rf a b c; mkdir a b c; touch a/f b/f; mv a/f b/f c 269 For now, it protects only regular files when copying (i.e., not renaming). 270 When renaming, it protects all non-directories. 271 Use dest_info_init to initialize it, or set it to NULL to disable 272 this feature. */ 273 Hash_table *dest_info; 274 275 /* FIXME */ 276 Hash_table *src_info; 277 }; 278 279 # define XSTAT(X, Src_name, Src_sb) \ 280 ((X)->dereference == DEREF_NEVER \ 281 ? lstat (Src_name, Src_sb) \ 282 : stat (Src_name, Src_sb)) 283 284 /* Arrange to make rename calls go through the wrapper function 285 on systems with a rename function that fails for a source file name 286 specified with a trailing slash. */ 287 # if RENAME_TRAILING_SLASH_BUG 288 int rpl_rename (const char *, const char *); 289 # undef rename 290 # define rename rpl_rename 291 # endif 292 293 bool copy (char const *src_name, char const *dst_name, 294 bool nonexistent_dst, const struct cp_options *options, 295 bool *copy_into_self, bool *rename_succeeded); 296 297 extern bool set_process_security_ctx (char const *src_name, 298 char const *dst_name, 299 mode_t mode, bool new_dst, 300 const struct cp_options *x); 301 302 extern bool set_file_security_ctx (char const *dst_name, bool process_local, 303 bool recurse, const struct cp_options *x); 304 305 void dest_info_init (struct cp_options *); 306 void src_info_init (struct cp_options *); 307 308 void cp_options_default (struct cp_options *); 309 bool chown_failure_ok (struct cp_options const *) _GL_ATTRIBUTE_PURE; 310 mode_t cached_umask (void); 311 312 #endif 313