diff options
Diffstat (limited to 'coreutils/ln.c')
-rw-r--r-- | coreutils/ln.c | 109 |
1 files changed, 109 insertions, 0 deletions
diff --git a/coreutils/ln.c b/coreutils/ln.c new file mode 100644 index 0000000..eb71719 --- /dev/null +++ b/coreutils/ln.c @@ -0,0 +1,109 @@ +/* vi: set sw=4 ts=4: */ +/* + * Mini ln implementation for busybox + * + * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org> + * + * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. + */ + +/* BB_AUDIT SUSv3 compliant */ +/* BB_AUDIT GNU options missing: -d, -F, -i, and -v. */ +/* http://www.opengroup.org/onlinepubs/007904975/utilities/ln.html */ + +#include "libbb.h" + +/* This is a NOEXEC applet. Be very careful! */ + + +#define LN_SYMLINK 1 +#define LN_FORCE 2 +#define LN_NODEREFERENCE 4 +#define LN_BACKUP 8 +#define LN_SUFFIX 16 + +int ln_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; +int ln_main(int argc, char **argv) +{ + int status = EXIT_SUCCESS; + int flag; + char *last; + char *src_name; + char *src; + char *suffix = (char*)"~"; + struct stat statbuf; + int (*link_func)(const char *, const char *); + + flag = getopt32(argv, "sfnbS:", &suffix); + + if (argc == optind) { + bb_show_usage(); + } + + last = argv[argc - 1]; + argv += optind; + + if (argc == optind + 1) { + *--argv = last; + last = bb_get_last_path_component_strip(xstrdup(last)); + } + + do { + src_name = NULL; + src = last; + + if (is_directory(src, + (flag & LN_NODEREFERENCE) ^ LN_NODEREFERENCE, + NULL) + ) { + src_name = xstrdup(*argv); + src = concat_path_file(src, bb_get_last_path_component_strip(src_name)); + free(src_name); + src_name = src; + } + if (!(flag & LN_SYMLINK) && stat(*argv, &statbuf)) { + // coreutils: "ln dangling_symlink new_hardlink" works + if (lstat(*argv, &statbuf) || !S_ISLNK(statbuf.st_mode)) { + bb_simple_perror_msg(*argv); + status = EXIT_FAILURE; + free(src_name); + continue; + } + } + + if (flag & LN_BACKUP) { + char *backup; + backup = xasprintf("%s%s", src, suffix); + if (rename(src, backup) < 0 && errno != ENOENT) { + bb_simple_perror_msg(src); + status = EXIT_FAILURE; + free(backup); + continue; + } + free(backup); + /* + * When the source and dest are both hard links to the same + * inode, a rename may succeed even though nothing happened. + * Therefore, always unlink(). + */ + unlink(src); + } else if (flag & LN_FORCE) { + unlink(src); + } + + link_func = link; + if (flag & LN_SYMLINK) { + link_func = symlink; + } + + if (link_func(*argv, src) != 0) { + bb_simple_perror_msg(src); + status = EXIT_FAILURE; + } + + free(src_name); + + } while ((++argv)[1]); + + return status; +} |