diff options
author | Denis Vlasenko <vda.linux@googlemail.com> | 2006-10-22 03:40:20 +0400 |
---|---|---|
committer | Denis Vlasenko <vda.linux@googlemail.com> | 2006-10-22 03:40:20 +0400 |
commit | f24e1f40e032e99cf57a05730e7632b825d3016d (patch) | |
tree | a6d0fa74d59e67d1570c54157f5ebcc47b4522d0 /libbb/copy_file.c | |
parent | 8d73c35916cbae67f5d0269b128de40f9992ddc6 (diff) |
cp: add support for -s, -l. Fix free(nonmalloc) bug.
Add doc on POSIX's rules on -i and -f (insane!).
ln: make "ln dangling_symlink new_link" work.
Diffstat (limited to 'libbb/copy_file.c')
-rw-r--r-- | libbb/copy_file.c | 210 |
1 files changed, 126 insertions, 84 deletions
diff --git a/libbb/copy_file.c b/libbb/copy_file.c index bd9c9f7a2..0135831fe 100644 --- a/libbb/copy_file.c +++ b/libbb/copy_file.c @@ -10,31 +10,53 @@ #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 = 0; int status = 0; + signed char dest_exists = 0; + signed char ovr; - if ((!(flags & FILEUTILS_DEREFERENCE) && - lstat(source, &source_stat) < 0) || - ((flags & FILEUTILS_DEREFERENCE) && - stat(source, &source_stat) < 0)) { - bb_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 (lstat(dest, &dest_stat) < 0) { if (errno != ENOENT) { - bb_perror_msg("unable to stat `%s'", dest); + bb_perror_msg("cannot stat '%s'", 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); + 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; @@ -46,14 +68,14 @@ int copy_file(const char *source, const char *dest, int flags) mode_t saved_umask = 0; if (!(flags & FILEUTILS_RECUR)) { - bb_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)) { - bb_error_msg("`%s' is not a directory", dest); + bb_error_msg("target '%s' is not a directory", dest); return -1; } } else { @@ -67,7 +89,7 @@ int copy_file(const char *source, const char *dest, int flags) if (mkdir(dest, mode) < 0) { umask(saved_umask); - bb_perror_msg("cannot create directory `%s'", dest); + bb_perror_msg("cannot create directory '%s'", dest); return -1; } @@ -75,7 +97,8 @@ int copy_file(const char *source, const char *dest, int flags) } /* Recursively copy files in SOURCE. */ - if ((dp = opendir(source)) == NULL) { + dp = opendir(source); + if (dp == NULL) { status = -1; goto preserve_status; } @@ -84,7 +107,7 @@ int copy_file(const char *source, const char *dest, int flags) char *new_source, *new_dest; new_source = concat_subpath_file(source, d->d_name); - if(new_source == NULL) + if (new_source == NULL) continue; new_dest = concat_path_file(dest, d->d_name); if (copy_file(new_source, new_dest, flags) < 0) @@ -92,103 +115,119 @@ int copy_file(const char *source, const char *dest, int flags) free(new_source); free(new_dest); } - /* closedir have only EBADF error, but "dp" not changes */ closedir(dp); - if (!dest_exists && - chmod(dest, source_stat.st_mode & ~saved_umask) < 0) { - bb_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) || - (S_ISLNK(source_stat.st_mode) && (flags & FILEUTILS_DEREFERENCE))) - { + + } 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; + + } 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 & FILEUTILS_DEREFERENCE) && - is_in_ino_dev_hashtable(&source_stat, &link_name)) { + if (!FLAGS_DEREF + && is_in_ino_dev_hashtable(&source_stat, &link_name) + ) { if (link(link_name, dest) < 0) { - bb_perror_msg("unable to link `%s'", dest); - return -1; + 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; + } } - return 0; } + // TODO: probably is_in_.. and add_to_... + // can be combined: find_or_add_... add_to_ino_dev_hashtable(&source_stat, dest); } + src_fd = open(source, O_RDONLY); if (src_fd == -1) { - bb_perror_msg("unable to open `%s'", source); - return(-1); + bb_perror_msg("cannot open '%s'", source); + return -1; } - if (dest_exists) { - if (flags & FILEUTILS_INTERACTIVE) { - fprintf(stderr, "%s: overwrite `%s'? ", applet_name, dest); - if (!bb_ask_confirmation()) { - close (src_fd); - return 0; - } - } - - dst_fd = open(dest, O_WRONLY|O_TRUNC); - if (dst_fd == -1) { - if (!(flags & FILEUTILS_FORCE)) { - bb_perror_msg("unable to open `%s'", dest); - close(src_fd); - return -1; - } - - if (unlink(dest) < 0) { - bb_perror_msg("unable to remove `%s'", dest); - close(src_fd); - return -1; - } - - goto dest_removed; + // 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; } - } else { -dest_removed: - dst_fd = open(dest, O_WRONLY|O_CREAT, source_stat.st_mode); + dst_fd = open(dest, O_WRONLY|O_CREAT|O_TRUNC, source_stat.st_mode); if (dst_fd == -1) { - bb_perror_msg("unable to open `%s'", dest); + bb_perror_msg("cannot open '%s'", dest); close(src_fd); - return(-1); + return -1; } } if (bb_copyfd_eof(src_fd, dst_fd) == -1) status = -1; - if (close(dst_fd) < 0) { - bb_perror_msg("unable to close `%s'", dest); + bb_perror_msg("cannot close '%s'", dest); status = -1; } - if (close(src_fd) < 0) { - bb_perror_msg("unable to close `%s'", source); + 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) || S_ISFIFO(source_stat.st_mode) || - S_ISLNK(source_stat.st_mode)) { + } 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) { - if((flags & FILEUTILS_FORCE) == 0) { - fprintf(stderr, "`%s' exists\n", dest); - return -1; - } - if(unlink(dest) < 0) { - bb_perror_msg("unable to remove `%s'", dest); - return -1; - } + ovr = retry_overwrite(dest, flags); + if (ovr <= 0) + return ovr; } if (S_ISFIFO(source_stat.st_mode)) { if (mkfifo(dest, source_stat.st_mode) < 0) { - bb_perror_msg("cannot create fifo `%s'", dest); + bb_perror_msg("cannot create fifo '%s'", dest); return -1; } } else if (S_ISLNK(source_stat.st_mode)) { @@ -196,20 +235,21 @@ dest_removed: lpath = xreadlink(source); if (symlink(lpath, dest) < 0) { - bb_perror_msg("cannot create symlink `%s'", dest); + bb_perror_msg("cannot create symlink '%s'", dest); + free(lpath); return -1; } free(lpath); if (flags & FILEUTILS_PRESERVE_STATUS) if (lchown(dest, source_stat.st_uid, source_stat.st_gid) < 0) - bb_perror_msg("unable to preserve ownership of `%s'", dest); + 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("unable to create `%s'", dest); + bb_perror_msg("cannot create '%s'", dest); return -1; } } @@ -218,22 +258,24 @@ dest_removed: return -1; } -preserve_status: + preserve_status: - if (flags & FILEUTILS_PRESERVE_STATUS) { + if (flags & FILEUTILS_PRESERVE_STATUS + /* Cannot happen: */ + /* && !(flags & (FILEUTILS_MAKE_SOFTLINK|FILEUTILS_MAKE_HARDLINK)) */ + ) { struct utimbuf times; - char *msg="unable to preserve %s of `%s'"; times.actime = source_stat.st_atime; times.modtime = source_stat.st_mtime; if (utime(dest, ×) < 0) - bb_perror_msg(msg, "times", 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); - bb_perror_msg(msg, "ownership", dest); + bb_perror_msg("cannot preserve %s of '%s'", "ownership", dest); } if (chmod(dest, source_stat.st_mode) < 0) - bb_perror_msg(msg, "permissions", dest); + bb_perror_msg("cannot preserve %s of '%s'", "permissions", dest); } return status; |