1 /* SPDX-License-Identifier: LGPL-2.1-or-later */
2 #pragma once
3
4 #include <dirent.h>
5 #include <stdbool.h>
6 #include <stdio.h>
7 #include <sys/socket.h>
8
9 #include "macro.h"
10 #include "stdio-util.h"
11
12 /* maximum length of fdname */
13 #define FDNAME_MAX 255
14
15 /* Make sure we can distinguish fd 0 and NULL */
16 #define FD_TO_PTR(fd) INT_TO_PTR((fd)+1)
17 #define PTR_TO_FD(p) (PTR_TO_INT(p)-1)
18
19 int close_nointr(int fd);
20 int safe_close(int fd);
21 void safe_close_pair(int p[static 2]);
22
safe_close_above_stdio(int fd)23 static inline int safe_close_above_stdio(int fd) {
24 if (fd < 3) /* Don't close stdin/stdout/stderr, but still invalidate the fd by returning -1 */
25 return -1;
26
27 return safe_close(fd);
28 }
29
30 void close_many(const int fds[], size_t n_fd);
31
32 int fclose_nointr(FILE *f);
33 FILE* safe_fclose(FILE *f);
34 DIR* safe_closedir(DIR *f);
35
closep(int * fd)36 static inline void closep(int *fd) {
37 safe_close(*fd);
38 }
39
close_pairp(int (* p)[2])40 static inline void close_pairp(int (*p)[2]) {
41 safe_close_pair(*p);
42 }
43
fclosep(FILE ** f)44 static inline void fclosep(FILE **f) {
45 safe_fclose(*f);
46 }
47
48 DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(FILE*, pclose, NULL);
49 DEFINE_TRIVIAL_CLEANUP_FUNC_FULL(DIR*, closedir, NULL);
50
51 #define _cleanup_close_ _cleanup_(closep)
52 #define _cleanup_fclose_ _cleanup_(fclosep)
53 #define _cleanup_pclose_ _cleanup_(pclosep)
54 #define _cleanup_closedir_ _cleanup_(closedirp)
55 #define _cleanup_close_pair_ _cleanup_(close_pairp)
56
57 int fd_nonblock(int fd, bool nonblock);
58 int fd_cloexec(int fd, bool cloexec);
59
60 int get_max_fd(void);
61
62 int close_all_fds(const int except[], size_t n_except);
63 int close_all_fds_without_malloc(const int except[], size_t n_except);
64
65 int same_fd(int a, int b);
66
67 void cmsg_close_all(struct msghdr *mh);
68
69 bool fdname_is_valid(const char *s);
70
71 int fd_get_path(int fd, char **ret);
72
73 int move_fd(int from, int to, int cloexec);
74
75 enum {
76 ACQUIRE_NO_DEV_NULL = 1 << 0,
77 ACQUIRE_NO_MEMFD = 1 << 1,
78 ACQUIRE_NO_PIPE = 1 << 2,
79 ACQUIRE_NO_TMPFILE = 1 << 3,
80 ACQUIRE_NO_REGULAR = 1 << 4,
81 };
82
83 int fd_move_above_stdio(int fd);
84
85 int rearrange_stdio(int original_input_fd, int original_output_fd, int original_error_fd);
86
make_null_stdio(void)87 static inline int make_null_stdio(void) {
88 return rearrange_stdio(-1, -1, -1);
89 }
90
91 /* Like TAKE_PTR() but for file descriptors, resetting them to -1 */
92 #define TAKE_FD(fd) \
93 ({ \
94 int *_fd_ = &(fd); \
95 int _ret_ = *_fd_; \
96 *_fd_ = -1; \
97 _ret_; \
98 })
99
100 /* Like free_and_replace(), but for file descriptors */
101 #define CLOSE_AND_REPLACE(a, b) \
102 ({ \
103 int *_fdp_ = &(a); \
104 safe_close(*_fdp_); \
105 *_fdp_ = TAKE_FD(b); \
106 0; \
107 })
108
109 int fd_reopen(int fd, int flags);
110 int read_nr_open(void);
111 int btrfs_defrag_fd(int fd);
112 int fd_get_diskseq(int fd, uint64_t *ret);
113
114 /* The maximum length a buffer for a /proc/self/fd/<fd> path needs */
115 #define PROC_FD_PATH_MAX \
116 (STRLEN("/proc/self/fd/") + DECIMAL_STR_MAX(int))
117
format_proc_fd_path(char buf[static PROC_FD_PATH_MAX],int fd)118 static inline char *format_proc_fd_path(char buf[static PROC_FD_PATH_MAX], int fd) {
119 assert(buf);
120 assert(fd >= 0);
121 assert_se(snprintf_ok(buf, PROC_FD_PATH_MAX, "/proc/self/fd/%i", fd));
122 return buf;
123 }
124
125 #define FORMAT_PROC_FD_PATH(fd) \
126 format_proc_fd_path((char[PROC_FD_PATH_MAX]) {}, (fd))
127