diff options
Diffstat (limited to 'src/basic/chase-symlinks.c')
| -rw-r--r-- | src/basic/chase-symlinks.c | 177 |
1 files changed, 177 insertions, 0 deletions
diff --git a/src/basic/chase-symlinks.c b/src/basic/chase-symlinks.c index 2eb1701e44..e3041ad6be 100644 --- a/src/basic/chase-symlinks.c +++ b/src/basic/chase-symlinks.c @@ -829,3 +829,180 @@ int chase_symlinks_at_and_open( return r; } +int chase_symlinks_at_and_opendir( + int dir_fd, + const char *path, + ChaseSymlinksFlags chase_flags, + char **ret_path, + DIR **ret_dir) { + + _cleanup_close_ int path_fd = -EBADF; + _cleanup_free_ char *p = NULL; + DIR *d; + int r; + + assert(!(chase_flags & (CHASE_NONEXISTENT|CHASE_STEP))); + assert(ret_dir); + + if (dir_fd == AT_FDCWD && !ret_path && + (chase_flags & (CHASE_NO_AUTOFS|CHASE_SAFE|CHASE_PROHIBIT_SYMLINKS|CHASE_PARENT|CHASE_MKDIR_0755)) == 0) { + /* Shortcut this call if none of the special features of this call are requested */ + d = opendir(path); + if (!d) + return -errno; + + *ret_dir = d; + return 0; + } + + r = chase_symlinks_at(dir_fd, path, chase_flags, ret_path ? &p : NULL, &path_fd); + if (r < 0) + return r; + assert(path_fd >= 0); + + d = xopendirat(path_fd, ".", O_NOFOLLOW); + if (!d) + return -errno; + + if (ret_path) + *ret_path = TAKE_PTR(p); + + *ret_dir = d; + return 0; +} + +int chase_symlinks_at_and_stat( + int dir_fd, + const char *path, + ChaseSymlinksFlags chase_flags, + char **ret_path, + struct stat *ret_stat) { + + _cleanup_close_ int path_fd = -EBADF; + _cleanup_free_ char *p = NULL; + int r; + + assert(path); + assert(!(chase_flags & (CHASE_NONEXISTENT|CHASE_STEP))); + assert(ret_stat); + + if (dir_fd == AT_FDCWD && !ret_path && + (chase_flags & (CHASE_NO_AUTOFS|CHASE_SAFE|CHASE_PROHIBIT_SYMLINKS|CHASE_PARENT|CHASE_MKDIR_0755)) == 0) + /* Shortcut this call if none of the special features of this call are requested */ + return RET_NERRNO(fstatat(AT_FDCWD, path, ret_stat, + FLAGS_SET(chase_flags, CHASE_NOFOLLOW) ? AT_SYMLINK_NOFOLLOW : 0)); + + r = chase_symlinks_at(dir_fd, path, chase_flags, ret_path ? &p : NULL, &path_fd); + if (r < 0) + return r; + assert(path_fd >= 0); + + if (fstat(path_fd, ret_stat) < 0) + return -errno; + + if (ret_path) + *ret_path = TAKE_PTR(p); + + return 0; +} + +int chase_symlinks_at_and_access( + int dir_fd, + const char *path, + ChaseSymlinksFlags chase_flags, + int access_mode, + char **ret_path) { + + _cleanup_close_ int path_fd = -EBADF; + _cleanup_free_ char *p = NULL; + int r; + + assert(path); + assert(!(chase_flags & (CHASE_NONEXISTENT|CHASE_STEP))); + + if (dir_fd == AT_FDCWD && !ret_path && + (chase_flags & (CHASE_NO_AUTOFS|CHASE_SAFE|CHASE_PROHIBIT_SYMLINKS|CHASE_PARENT|CHASE_MKDIR_0755)) == 0) + /* Shortcut this call if none of the special features of this call are requested */ + return RET_NERRNO(faccessat(AT_FDCWD, path, access_mode, + FLAGS_SET(chase_flags, CHASE_NOFOLLOW) ? AT_SYMLINK_NOFOLLOW : 0)); + + r = chase_symlinks_at(dir_fd, path, chase_flags, ret_path ? &p : NULL, &path_fd); + if (r < 0) + return r; + assert(path_fd >= 0); + + r = access_fd(path_fd, access_mode); + if (r < 0) + return r; + + if (ret_path) + *ret_path = TAKE_PTR(p); + + return 0; +} + +int chase_symlinks_at_and_fopen_unlocked( + int dir_fd, + const char *path, + ChaseSymlinksFlags chase_flags, + const char *open_flags, + char **ret_path, + FILE **ret_file) { + + _cleanup_free_ char *final_path = NULL; + _cleanup_close_ int fd = -EBADF; + int mode_flags, r; + + assert(path); + assert(!(chase_flags & (CHASE_NONEXISTENT|CHASE_STEP|CHASE_PARENT))); + assert(open_flags); + assert(ret_file); + + mode_flags = fopen_mode_to_flags(open_flags); + if (mode_flags < 0) + return mode_flags; + + fd = chase_symlinks_at_and_open(dir_fd, path, chase_flags, mode_flags, ret_path ? &final_path : NULL); + if (fd < 0) + return fd; + + r = take_fdopen_unlocked(&fd, open_flags, ret_file); + if (r < 0) + return r; + + if (ret_path) + *ret_path = TAKE_PTR(final_path); + + return 0; +} + +int chase_symlinks_at_and_unlink( + int dir_fd, + const char *path, + ChaseSymlinksFlags chase_flags, + int unlink_flags, + char **ret_path) { + + _cleanup_free_ char *p = NULL, *fname = NULL; + _cleanup_close_ int fd = -EBADF; + int r; + + assert(path); + assert(!(chase_flags & (CHASE_NONEXISTENT|CHASE_STEP|CHASE_PARENT))); + + fd = chase_symlinks_at_and_open(dir_fd, path, chase_flags|CHASE_PARENT|CHASE_NOFOLLOW, O_PATH|O_DIRECTORY|O_CLOEXEC, &p); + if (fd < 0) + return fd; + + r = path_extract_filename(p, &fname); + if (r < 0) + return r; + + if (unlinkat(fd, fname, unlink_flags) < 0) + return -errno; + + if (ret_path) + *ret_path = TAKE_PTR(p); + + return 0; +} |