src/basic/fs-util.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 /***
   5   This file is part of systemd.
   6
   7   Copyright 2010 Lennart Poettering
   8 ***/
   9
  10 #include <dirent.h>
  11 #include <fcntl.h>
  12 #include <limits.h>
  13 #include <stdbool.h>
  14 #include <stdint.h>
  15 #include <sys/inotify.h>
  16 #include <sys/types.h>
  17 #include <unistd.h>
  18
  19 #include "time-util.h"
  20 #include "util.h"
  21
  22 int unlink_noerrno(const char *path);
  23
  24 int rmdir_parents(const char *path, const char *stop);
  25
  26 int rename_noreplace(int olddirfd, const char *oldpath, int newdirfd, const char *newpath);
  27
  28 int readlinkat_malloc(int fd, const char *p, char **ret);
  29 int readlink_malloc(const char *p, char **r);
  30 int readlink_value(const char *p, char **ret);
  31 int readlink_and_make_absolute(const char *p, char **r);
  32
  33 int chmod_and_chown(const char *path, mode_t mode, uid_t uid, gid_t gid);
  34
  35 int fchmod_umask(int fd, mode_t mode);
  36 int fchmod_opath(int fd, mode_t m);
  37
  38 int fd_warn_permissions(const char *path, int fd);
  39
  40 #define laccess(path, mode) faccessat(AT_FDCWD, (path), (mode), AT_SYMLINK_NOFOLLOW)
  41
  42 int touch_file(const char *path, bool parents, usec_t stamp, uid_t uid, gid_t gid, mode_t mode);
  43 int touch(const char *path);
  44
  45 int symlink_idempotent(const char *from, const char *to);
  46
  47 int symlink_atomic(const char *from, const char *to);
  48 int mknod_atomic(const char *path, mode_t mode, dev_t dev);
  49 int mkfifo_atomic(const char *path, mode_t mode);
  50
  51 int get_files_in_directory(const char *path, char ***list);
  52
  53 int tmp_dir(const char **ret);
  54 int var_tmp_dir(const char **ret);
  55
  56 int unlink_or_warn(const char *filename);
  57
  58 #define INOTIFY_EVENT_MAX (sizeof(struct inotify_event) + NAME_MAX + 1)
  59
  60 #define FOREACH_INOTIFY_EVENT(e, buffer, sz) \
  61         for ((e) = &buffer.ev;                                \
  62              (uint8_t*) (e) < (uint8_t*) (buffer.raw) + (sz); \
  63              (e) = (struct inotify_event*) ((uint8_t*) (e) + sizeof(struct inotify_event) + (e)->len))
  64
  65 union inotify_event_buffer {
  66         struct inotify_event ev;
  67         uint8_t raw[INOTIFY_EVENT_MAX];
  68 };
  69
  70 int inotify_add_watch_fd(int fd, int what, uint32_t mask);
  71
  72 enum {
  73         CHASE_PREFIX_ROOT = 1U << 0,   /* If set, the specified path will be prefixed by the specified root before beginning the iteration */
  74         CHASE_NONEXISTENT = 1U << 1,   /* If set, it's OK if the path doesn't actually exist. */
  75         CHASE_NO_AUTOFS   = 1U << 2,   /* If set, return -EREMOTE if autofs mount point found */
  76         CHASE_SAFE        = 1U << 3,   /* If set, return EPERM if we ever traverse from unprivileged to privileged files or directories */
  77         CHASE_OPEN        = 1U << 4,   /* If set, return an O_PATH object to the final component */
  78         CHASE_TRAIL_SLASH = 1U << 5,   /* If set, any trailing slash will be preserved */
  79         CHASE_STEP        = 1U << 6,   /* If set, just execute a single step of the normalization */
  80 };
  81
  82 /* How many iterations to execute before returning -ELOOP */
  83 #define CHASE_SYMLINKS_MAX 32
  84
  85 int chase_symlinks(const char *path_with_prefix, const char *root, unsigned flags, char **ret);
  86
  87 int chase_symlinks_and_open(const char *path, const char *root, unsigned chase_flags, int open_flags, char **ret_path);
  88 int chase_symlinks_and_opendir(const char *path, const char *root, unsigned chase_flags, char **ret_path, DIR **ret_dir);
  89 int chase_symlinks_and_stat(const char *path, const char *root, unsigned chase_flags, char **ret_path, struct stat *ret_stat);
  90
  91 /* Useful for usage with _cleanup_(), removes a directory and frees the pointer */
  92 static inline void rmdir_and_free(char *p) {
  93         PROTECT_ERRNO;
  94         (void) rmdir(p);
  95         free(p);
  96 }
  97 DEFINE_TRIVIAL_CLEANUP_FUNC(char*, rmdir_and_free);
  98
  99 static inline void unlink_and_free(char *p) {
 100         (void) unlink_noerrno(p);
 101         free(p);
 102 }
 103 DEFINE_TRIVIAL_CLEANUP_FUNC(char*, unlink_and_free);
 104
 105 int access_fd(int fd, int mode);
 106
 107 void unlink_tempfilep(char (*p)[]);
 108 int unlinkat_deallocate(int fd, const char *name, int flags);
 109
 110 int fsync_directory_of_file(int fd);