Contents of /trunk/mkinitrd-magellan/busybox/libbb/copy_file.c
Parent Directory | Revision Log
Revision 532 -
(show annotations)
(download)
Sat Sep 1 22:45:15 2007 UTC (17 years ago) by niro
File MIME type: text/plain
File size: 7432 byte(s)
Sat Sep 1 22:45:15 2007 UTC (17 years ago) by niro
File MIME type: text/plain
File size: 7432 byte(s)
-import if magellan mkinitrd; it is a fork of redhats mkinitrd-5.0.8 with all magellan patches and features; deprecates magellan-src/mkinitrd
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 "libbb.h" |
12 | |
13 | static int retry_overwrite(const char *dest, int flags) |
14 | { |
15 | if (!(flags & (FILEUTILS_FORCE|FILEUTILS_INTERACTIVE))) { |
16 | fprintf(stderr, "'%s' exists\n", dest); |
17 | return -1; |
18 | } |
19 | if (flags & FILEUTILS_INTERACTIVE) { |
20 | fprintf(stderr, "%s: overwrite '%s'? ", applet_name, dest); |
21 | if (!bb_ask_confirmation()) |
22 | return 0; // not allowed to overwrite |
23 | } |
24 | if (unlink(dest) < 0) { |
25 | bb_perror_msg("cannot remove '%s'", dest); |
26 | return -1; // error |
27 | } |
28 | return 1; // ok (to try again) |
29 | } |
30 | |
31 | int copy_file(const char *source, const char *dest, int flags) |
32 | { |
33 | struct stat source_stat; |
34 | struct stat dest_stat; |
35 | int status = 0; |
36 | signed char dest_exists = 0; |
37 | signed char ovr; |
38 | |
39 | #define FLAGS_DEREF (flags & FILEUTILS_DEREFERENCE) |
40 | |
41 | if ((FLAGS_DEREF ? stat : lstat)(source, &source_stat) < 0) { |
42 | // This may be a dangling symlink. |
43 | // Making [sym]links to dangling symlinks works, so... |
44 | if (flags & (FILEUTILS_MAKE_SOFTLINK|FILEUTILS_MAKE_HARDLINK)) |
45 | goto make_links; |
46 | bb_perror_msg("cannot stat '%s'", source); |
47 | return -1; |
48 | } |
49 | |
50 | if (lstat(dest, &dest_stat) < 0) { |
51 | if (errno != ENOENT) { |
52 | bb_perror_msg("cannot stat '%s'", dest); |
53 | return -1; |
54 | } |
55 | } else { |
56 | if (source_stat.st_dev == dest_stat.st_dev |
57 | && source_stat.st_ino == dest_stat.st_ino |
58 | ) { |
59 | bb_error_msg("'%s' and '%s' are the same file", source, dest); |
60 | return -1; |
61 | } |
62 | dest_exists = 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 | bb_error_msg("omitting directory '%s'", source); |
72 | return -1; |
73 | } |
74 | |
75 | /* Create DEST. */ |
76 | if (dest_exists) { |
77 | if (!S_ISDIR(dest_stat.st_mode)) { |
78 | bb_error_msg("target '%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 | bb_perror_msg("cannot create directory '%s'", dest); |
93 | return -1; |
94 | } |
95 | |
96 | umask(saved_umask); |
97 | } |
98 | |
99 | /* Recursively copy files in SOURCE. */ |
100 | dp = opendir(source); |
101 | if (dp == NULL) { |
102 | status = -1; |
103 | goto preserve_status; |
104 | } |
105 | |
106 | while ((d = readdir(dp)) != NULL) { |
107 | char *new_source, *new_dest; |
108 | |
109 | new_source = concat_subpath_file(source, d->d_name); |
110 | if (new_source == NULL) |
111 | continue; |
112 | new_dest = concat_path_file(dest, d->d_name); |
113 | if (copy_file(new_source, new_dest, flags) < 0) |
114 | status = -1; |
115 | free(new_source); |
116 | free(new_dest); |
117 | } |
118 | closedir(dp); |
119 | |
120 | if (!dest_exists |
121 | && chmod(dest, source_stat.st_mode & ~saved_umask) < 0 |
122 | ) { |
123 | bb_perror_msg("cannot change permissions of '%s'", dest); |
124 | status = -1; |
125 | } |
126 | |
127 | } else if (flags & (FILEUTILS_MAKE_SOFTLINK|FILEUTILS_MAKE_HARDLINK)) { |
128 | int (*lf)(const char *oldpath, const char *newpath); |
129 | make_links: |
130 | // Hmm... maybe |
131 | // if (DEREF && MAKE_SOFTLINK) source = realpath(source) ? |
132 | // (but realpath returns NULL on dangling symlinks...) |
133 | lf = (flags & FILEUTILS_MAKE_SOFTLINK) ? symlink : link; |
134 | if (lf(source, dest) < 0) { |
135 | ovr = retry_overwrite(dest, flags); |
136 | if (ovr <= 0) |
137 | return ovr; |
138 | if (lf(source, dest) < 0) { |
139 | bb_perror_msg("cannot create link '%s'", dest); |
140 | return -1; |
141 | } |
142 | } |
143 | return 0; |
144 | |
145 | } else if (S_ISREG(source_stat.st_mode) |
146 | // Huh? DEREF uses stat, which never returns links IIRC... |
147 | || (FLAGS_DEREF && S_ISLNK(source_stat.st_mode)) |
148 | ) { |
149 | int src_fd; |
150 | int dst_fd; |
151 | if (ENABLE_FEATURE_PRESERVE_HARDLINKS) { |
152 | char *link_name; |
153 | |
154 | if (!FLAGS_DEREF |
155 | && is_in_ino_dev_hashtable(&source_stat, &link_name) |
156 | ) { |
157 | if (link(link_name, dest) < 0) { |
158 | ovr = retry_overwrite(dest, flags); |
159 | if (ovr <= 0) |
160 | return ovr; |
161 | if (link(link_name, dest) < 0) { |
162 | bb_perror_msg("cannot create link '%s'", dest); |
163 | return -1; |
164 | } |
165 | } |
166 | return 0; |
167 | } |
168 | // TODO: probably is_in_.. and add_to_... |
169 | // can be combined: find_or_add_... |
170 | add_to_ino_dev_hashtable(&source_stat, dest); |
171 | } |
172 | |
173 | src_fd = open(source, O_RDONLY); |
174 | if (src_fd == -1) { |
175 | bb_perror_msg("cannot open '%s'", source); |
176 | return -1; |
177 | } |
178 | |
179 | // POSIX: if exists and -i, ask (w/o -i assume yes). |
180 | // Then open w/o EXCL. |
181 | // If open still fails and -f, try unlink, then try open again. |
182 | // Result: a mess: |
183 | // If dest is a softlink, we overwrite softlink's destination! |
184 | // (or fail, if it points to dir/nonexistent location/etc). |
185 | // This is strange, but POSIX-correct. |
186 | // coreutils cp has --remove-destination to override this... |
187 | dst_fd = open(dest, (flags & FILEUTILS_INTERACTIVE) |
188 | ? O_WRONLY|O_CREAT|O_TRUNC|O_EXCL |
189 | : O_WRONLY|O_CREAT|O_TRUNC, source_stat.st_mode); |
190 | if (dst_fd == -1) { |
191 | // We would not do POSIX insanity. -i asks, |
192 | // then _unlinks_ the offender. Presto. |
193 | // Or else we will end up having 3 open()s! |
194 | ovr = retry_overwrite(dest, flags); |
195 | if (ovr <= 0) { |
196 | close(src_fd); |
197 | return ovr; |
198 | } |
199 | dst_fd = open(dest, O_WRONLY|O_CREAT|O_TRUNC, source_stat.st_mode); |
200 | if (dst_fd == -1) { |
201 | bb_perror_msg("cannot open '%s'", dest); |
202 | close(src_fd); |
203 | return -1; |
204 | } |
205 | } |
206 | |
207 | if (bb_copyfd_eof(src_fd, dst_fd) == -1) |
208 | status = -1; |
209 | if (close(dst_fd) < 0) { |
210 | bb_perror_msg("cannot close '%s'", dest); |
211 | status = -1; |
212 | } |
213 | if (close(src_fd) < 0) { |
214 | bb_perror_msg("cannot close '%s'", source); |
215 | status = -1; |
216 | } |
217 | |
218 | } else if (S_ISBLK(source_stat.st_mode) || S_ISCHR(source_stat.st_mode) |
219 | || S_ISSOCK(source_stat.st_mode) || S_ISFIFO(source_stat.st_mode) |
220 | || S_ISLNK(source_stat.st_mode) |
221 | ) { |
222 | // We are lazy here, a bit lax with races... |
223 | if (dest_exists) { |
224 | ovr = retry_overwrite(dest, flags); |
225 | if (ovr <= 0) |
226 | return ovr; |
227 | } |
228 | if (S_ISFIFO(source_stat.st_mode)) { |
229 | if (mkfifo(dest, source_stat.st_mode) < 0) { |
230 | bb_perror_msg("cannot create fifo '%s'", dest); |
231 | return -1; |
232 | } |
233 | } else if (S_ISLNK(source_stat.st_mode)) { |
234 | char *lpath; |
235 | |
236 | lpath = xreadlink(source); |
237 | if (symlink(lpath, dest) < 0) { |
238 | bb_perror_msg("cannot create symlink '%s'", dest); |
239 | free(lpath); |
240 | return -1; |
241 | } |
242 | free(lpath); |
243 | |
244 | if (flags & FILEUTILS_PRESERVE_STATUS) |
245 | if (lchown(dest, source_stat.st_uid, source_stat.st_gid) < 0) |
246 | bb_perror_msg("cannot preserve %s of '%s'", "ownership", dest); |
247 | |
248 | return 0; |
249 | |
250 | } else { |
251 | if (mknod(dest, source_stat.st_mode, source_stat.st_rdev) < 0) { |
252 | bb_perror_msg("cannot create '%s'", dest); |
253 | return -1; |
254 | } |
255 | } |
256 | } else { |
257 | bb_error_msg("internal error: unrecognized file type"); |
258 | return -1; |
259 | } |
260 | |
261 | preserve_status: |
262 | |
263 | if (flags & FILEUTILS_PRESERVE_STATUS |
264 | /* Cannot happen: */ |
265 | /* && !(flags & (FILEUTILS_MAKE_SOFTLINK|FILEUTILS_MAKE_HARDLINK)) */ |
266 | ) { |
267 | struct utimbuf times; |
268 | |
269 | times.actime = source_stat.st_atime; |
270 | times.modtime = source_stat.st_mtime; |
271 | if (utime(dest, ×) < 0) |
272 | bb_perror_msg("cannot preserve %s of '%s'", "times", dest); |
273 | if (chown(dest, source_stat.st_uid, source_stat.st_gid) < 0) { |
274 | source_stat.st_mode &= ~(S_ISUID | S_ISGID); |
275 | bb_perror_msg("cannot preserve %s of '%s'", "ownership", dest); |
276 | } |
277 | if (chmod(dest, source_stat.st_mode) < 0) |
278 | bb_perror_msg("cannot preserve %s of '%s'", "permissions", dest); |
279 | } |
280 | |
281 | return status; |
282 | } |