/*
* Mini copy_file implementation for busybox
*
- *
* Copyright (C) 2001 by Matt Kraai <kraai@alumni.carnegiemellon.edu>
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
*
*/
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <unistd.h>
-#include <fcntl.h>
-#include <utime.h>
-#include <errno.h>
-#include <dirent.h>
-#include <stdlib.h>
-
#include "libbb.h"
+static int retry_overwrite(const char *dest, int flags)
+{
+ if (!(flags & (FILEUTILS_FORCE|FILEUTILS_INTERACTIVE))) {
+ fprintf(stderr, "'%s' exists\n", dest);
+ return -1;
+ }
+ if (flags & FILEUTILS_INTERACTIVE) {
+ fprintf(stderr, "%s: overwrite '%s'? ", applet_name, dest);
+ if (!bb_ask_confirmation())
+ return 0; // not allowed to overwrite
+ }
+ if (unlink(dest) < 0) {
+ bb_perror_msg("cannot remove '%s'", dest);
+ return -1; // error
+ }
+ return 1; // ok (to try again)
+}
+
int copy_file(const char *source, const char *dest, int flags)
{
struct stat source_stat;
struct stat dest_stat;
- int dest_exists = 1;
int status = 0;
+ signed char dest_exists = 0;
+ signed char ovr;
- if (((flags & FILEUTILS_PRESERVE_SYMLINKS) &&
- lstat(source, &source_stat) < 0) ||
- (!(flags & FILEUTILS_PRESERVE_SYMLINKS) &&
- stat(source, &source_stat) < 0)) {
- perror_msg("%s", source);
+#define FLAGS_DEREF (flags & FILEUTILS_DEREFERENCE)
+
+ if ((FLAGS_DEREF ? stat : lstat)(source, &source_stat) < 0) {
+ // This may be a dangling symlink.
+ // Making [sym]links to dangling symlinks works, so...
+ if (flags & (FILEUTILS_MAKE_SOFTLINK|FILEUTILS_MAKE_HARDLINK))
+ goto make_links;
+ bb_perror_msg("cannot stat '%s'", source);
return -1;
}
- if (stat(dest, &dest_stat) < 0) {
+ if (lstat(dest, &dest_stat) < 0) {
if (errno != ENOENT) {
- perror_msg("unable to stat `%s'", dest);
+ bb_perror_msg("cannot stat '%s'", dest);
return -1;
}
- dest_exists = 0;
- }
-
- if (dest_exists && source_stat.st_rdev == dest_stat.st_rdev &&
- source_stat.st_ino == dest_stat.st_ino) {
- error_msg("`%s' and `%s' are the same file", source, dest);
- return -1;
+ } else {
+ if (source_stat.st_dev == dest_stat.st_dev
+ && source_stat.st_ino == dest_stat.st_ino
+ ) {
+ bb_error_msg("'%s' and '%s' are the same file", source, dest);
+ return -1;
+ }
+ dest_exists = 1;
}
if (S_ISDIR(source_stat.st_mode)) {
mode_t saved_umask = 0;
if (!(flags & FILEUTILS_RECUR)) {
- error_msg("%s: omitting directory", source);
+ bb_error_msg("omitting directory '%s'", source);
return -1;
}
/* Create DEST. */
if (dest_exists) {
if (!S_ISDIR(dest_stat.st_mode)) {
- error_msg("`%s' is not a directory", dest);
+ bb_error_msg("target '%s' is not a directory", dest);
return -1;
}
} else {
if (mkdir(dest, mode) < 0) {
umask(saved_umask);
- perror_msg("cannot create directory `%s'", dest);
+ bb_perror_msg("cannot create directory '%s'", dest);
return -1;
}
umask(saved_umask);
}
-
+
/* Recursively copy files in SOURCE. */
- if ((dp = opendir(source)) == NULL) {
- perror_msg("unable to open directory `%s'", source);
+ dp = opendir(source);
+ if (dp == NULL) {
status = -1;
- goto end;
+ goto preserve_status;
}
while ((d = readdir(dp)) != NULL) {
char *new_source, *new_dest;
- if (strcmp(d->d_name, ".") == 0 ||
- strcmp(d->d_name, "..") == 0)
+ new_source = concat_subpath_file(source, d->d_name);
+ if (new_source == NULL)
continue;
-
- new_source = concat_path_file(source, d->d_name);
new_dest = concat_path_file(dest, d->d_name);
if (copy_file(new_source, new_dest, flags) < 0)
status = -1;
free(new_source);
free(new_dest);
}
-
- /* ??? What if an error occurs in readdir? */
-
- if (closedir(dp) < 0) {
- perror_msg("unable to close directory `%s'", source);
- status = -1;
- }
+ closedir(dp);
- if (!dest_exists &&
- chmod(dest, source_stat.st_mode & ~saved_umask) < 0) {
- perror_msg("unable to change permissions of `%s'", dest);
+ if (!dest_exists
+ && chmod(dest, source_stat.st_mode & ~saved_umask) < 0
+ ) {
+ bb_perror_msg("cannot change permissions of '%s'", dest);
status = -1;
}
- } else if (S_ISREG(source_stat.st_mode)) {
- FILE *sfp, *dfp;
- if (dest_exists) {
- if (flags & FILEUTILS_INTERACTIVE) {
- fprintf(stderr, "%s: overwrite `%s'? ", applet_name, dest);
- if (!ask_confirmation())
- return 0;
+ } else if (flags & (FILEUTILS_MAKE_SOFTLINK|FILEUTILS_MAKE_HARDLINK)) {
+ int (*lf)(const char *oldpath, const char *newpath);
+ make_links:
+ // Hmm... maybe
+ // if (DEREF && MAKE_SOFTLINK) source = realpath(source) ?
+ // (but realpath returns NULL on dangling symlinks...)
+ lf = (flags & FILEUTILS_MAKE_SOFTLINK) ? symlink : link;
+ if (lf(source, dest) < 0) {
+ ovr = retry_overwrite(dest, flags);
+ if (ovr <= 0)
+ return ovr;
+ if (lf(source, dest) < 0) {
+ bb_perror_msg("cannot create link '%s'", dest);
+ return -1;
}
+ }
+ return 0;
- if ((dfp = fopen(dest, "w")) == NULL) {
- if (!(flags & FILEUTILS_FORCE)) {
- perror_msg("unable to open `%s'", dest);
- return -1;
- }
-
- if (unlink(dest) < 0) {
- perror_msg("unable to remove `%s'", dest);
- return -1;
+ } else if (S_ISREG(source_stat.st_mode)
+ // Huh? DEREF uses stat, which never returns links IIRC...
+ || (FLAGS_DEREF && S_ISLNK(source_stat.st_mode))
+ ) {
+ int src_fd;
+ int dst_fd;
+ if (ENABLE_FEATURE_PRESERVE_HARDLINKS) {
+ char *link_name;
+
+ if (!FLAGS_DEREF
+ && is_in_ino_dev_hashtable(&source_stat, &link_name)
+ ) {
+ if (link(link_name, dest) < 0) {
+ ovr = retry_overwrite(dest, flags);
+ if (ovr <= 0)
+ return ovr;
+ if (link(link_name, dest) < 0) {
+ bb_perror_msg("cannot create link '%s'", dest);
+ return -1;
+ }
}
-
- dest_exists = 0;
+ return 0;
}
+ // TODO: probably is_in_.. and add_to_...
+ // can be combined: find_or_add_...
+ add_to_ino_dev_hashtable(&source_stat, dest);
}
- if (!dest_exists) {
- int fd;
+ src_fd = open(source, O_RDONLY);
+ if (src_fd == -1) {
+ bb_perror_msg("cannot open '%s'", source);
+ return -1;
+ }
- if ((fd = open(dest, O_WRONLY|O_CREAT, source_stat.st_mode)) < 0 ||
- (dfp = fdopen(fd, "w")) == NULL) {
- if (fd >= 0)
- close(fd);
- perror_msg("unable to open `%s'", dest);
+ // POSIX: if exists and -i, ask (w/o -i assume yes).
+ // Then open w/o EXCL.
+ // If open still fails and -f, try unlink, then try open again.
+ // Result: a mess:
+ // If dest is a softlink, we overwrite softlink's destination!
+ // (or fail, if it points to dir/nonexistent location/etc).
+ // This is strange, but POSIX-correct.
+ // coreutils cp has --remove-destination to override this...
+ dst_fd = open(dest, (flags & FILEUTILS_INTERACTIVE)
+ ? O_WRONLY|O_CREAT|O_TRUNC|O_EXCL
+ : O_WRONLY|O_CREAT|O_TRUNC, source_stat.st_mode);
+ if (dst_fd == -1) {
+ // We would not do POSIX insanity. -i asks,
+ // then _unlinks_ the offender. Presto.
+ // Or else we will end up having 3 open()s!
+ ovr = retry_overwrite(dest, flags);
+ if (ovr <= 0) {
+ close(src_fd);
+ return ovr;
+ }
+ dst_fd = open(dest, O_WRONLY|O_CREAT|O_TRUNC, source_stat.st_mode);
+ if (dst_fd == -1) {
+ bb_perror_msg("cannot open '%s'", dest);
+ close(src_fd);
return -1;
}
}
- if ((sfp = fopen(source, "r")) == NULL) {
- fclose(dfp);
- perror_msg("unable to open `%s'", source);
+ if (bb_copyfd_eof(src_fd, dst_fd) == -1)
status = -1;
- goto end;
- }
-
- copy_file_chunk(sfp, dfp, source_stat.st_size);
-
- if (fclose(dfp) < 0) {
- perror_msg("unable to close `%s'", dest);
+ if (close(dst_fd) < 0) {
+ bb_perror_msg("cannot close '%s'", dest);
status = -1;
}
-
- if (fclose(sfp) < 0) {
- perror_msg("unable to close `%s'", source);
+ if (close(src_fd) < 0) {
+ bb_perror_msg("cannot close '%s'", source);
status = -1;
}
- } else if (S_ISBLK(source_stat.st_mode) || S_ISCHR(source_stat.st_mode) ||
- S_ISSOCK(source_stat.st_mode)) {
- if (mknod(dest, source_stat.st_mode, source_stat.st_rdev) < 0) {
- perror_msg("unable to create `%s'", dest);
- return -1;
- }
- } else if (S_ISFIFO(source_stat.st_mode)) {
- if (mkfifo(dest, source_stat.st_mode) < 0) {
- perror_msg("cannot create fifo `%s'", dest);
- return -1;
- }
- } else if (S_ISLNK(source_stat.st_mode)) {
- int size;
- char buf[BUFSIZ + 1];
- if ((size = readlink(source, buf, BUFSIZ)) < 0) {
- perror_msg("cannot read `%s'", source);
- return -1;
+ } else if (S_ISBLK(source_stat.st_mode) || S_ISCHR(source_stat.st_mode)
+ || S_ISSOCK(source_stat.st_mode) || S_ISFIFO(source_stat.st_mode)
+ || S_ISLNK(source_stat.st_mode)
+ ) {
+ // We are lazy here, a bit lax with races...
+ if (dest_exists) {
+ ovr = retry_overwrite(dest, flags);
+ if (ovr <= 0)
+ return ovr;
}
- buf[size] = '\0';
+ if (S_ISFIFO(source_stat.st_mode)) {
+ if (mkfifo(dest, source_stat.st_mode) < 0) {
+ bb_perror_msg("cannot create fifo '%s'", dest);
+ return -1;
+ }
+ } else if (S_ISLNK(source_stat.st_mode)) {
+ char *lpath;
- if (symlink(buf, dest) < 0) {
- perror_msg("cannot create symlink `%s'", dest);
- return -1;
- }
+ lpath = xreadlink(source);
+ if (symlink(lpath, dest) < 0) {
+ bb_perror_msg("cannot create symlink '%s'", dest);
+ free(lpath);
+ return -1;
+ }
+ free(lpath);
-#if (__GLIBC__ >= 2) && (__GLIBC_MINOR__ >= 1)
- if (flags & FILEUTILS_PRESERVE_STATUS)
- if (lchown(dest, source_stat.st_uid, source_stat.st_gid) < 0)
- perror_msg("unable to preserve ownership of `%s'", dest);
-#endif
- return 0;
+ if (flags & FILEUTILS_PRESERVE_STATUS)
+ if (lchown(dest, source_stat.st_uid, source_stat.st_gid) < 0)
+ bb_perror_msg("cannot preserve %s of '%s'", "ownership", dest);
+
+ return 0;
+
+ } else {
+ if (mknod(dest, source_stat.st_mode, source_stat.st_rdev) < 0) {
+ bb_perror_msg("cannot create '%s'", dest);
+ return -1;
+ }
+ }
} else {
- error_msg("internal error: unrecognized file type");
+ bb_error_msg("internal error: unrecognized file type");
return -1;
}
-end:
+ preserve_status:
- if (flags & FILEUTILS_PRESERVE_STATUS) {
+ if (flags & FILEUTILS_PRESERVE_STATUS
+ /* Cannot happen: */
+ /* && !(flags & (FILEUTILS_MAKE_SOFTLINK|FILEUTILS_MAKE_HARDLINK)) */
+ ) {
struct utimbuf times;
times.actime = source_stat.st_atime;
times.modtime = source_stat.st_mtime;
if (utime(dest, ×) < 0)
- perror_msg("unable to preserve times of `%s'", dest);
+ bb_perror_msg("cannot preserve %s of '%s'", "times", dest);
if (chown(dest, source_stat.st_uid, source_stat.st_gid) < 0) {
source_stat.st_mode &= ~(S_ISUID | S_ISGID);
- perror_msg("unable to preserve ownership of `%s'", dest);
+ bb_perror_msg("cannot preserve %s of '%s'", "ownership", dest);
}
if (chmod(dest, source_stat.st_mode) < 0)
- perror_msg("unable to preserve permissions of `%s'", dest);
+ bb_perror_msg("cannot preserve %s of '%s'", "permissions", dest);
}
return status;
projects / oweals / busybox.git / blobdiff