summaryrefslogtreecommitdiffstats
path: root/src/basic/fileio.h
blob: 03c3f3ff2839376310ca7cd6afb9308baac47c4e (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
/* SPDX-License-Identifier: LGPL-2.1-or-later */
#pragma once

#include <dirent.h>
#include <fcntl.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdio.h>
#include <sys/stat.h>
#include <sys/types.h>

#include "macro.h"
#include "time-util.h"

#define LONG_LINE_MAX (1U*1024U*1024U)

typedef enum {
        WRITE_STRING_FILE_CREATE                     = 1 << 0,
        WRITE_STRING_FILE_TRUNCATE                   = 1 << 1,
        WRITE_STRING_FILE_ATOMIC                     = 1 << 2,
        WRITE_STRING_FILE_AVOID_NEWLINE              = 1 << 3,
        WRITE_STRING_FILE_VERIFY_ON_FAILURE          = 1 << 4,
        WRITE_STRING_FILE_VERIFY_IGNORE_NEWLINE      = 1 << 5,
        WRITE_STRING_FILE_SYNC                       = 1 << 6,
        WRITE_STRING_FILE_DISABLE_BUFFER             = 1 << 7,
        WRITE_STRING_FILE_NOFOLLOW                   = 1 << 8,
        WRITE_STRING_FILE_MKDIR_0755                 = 1 << 9,
        WRITE_STRING_FILE_MODE_0600                  = 1 << 10,
        WRITE_STRING_FILE_MODE_0444                  = 1 << 11,
        WRITE_STRING_FILE_SUPPRESS_REDUNDANT_VIRTUAL = 1 << 12,

        /* And before you wonder, why write_string_file_atomic_label_ts() is a separate function instead of just one
           more flag here: it's about linking: we don't want to pull -lselinux into all users of write_string_file()
           and friends. */

} WriteStringFileFlags;

typedef enum {
        READ_FULL_FILE_SECURE              = 1 << 0, /* erase any buffers we employ internally, after use */
        READ_FULL_FILE_UNBASE64            = 1 << 1, /* base64 decode what we read */
        READ_FULL_FILE_UNHEX               = 1 << 2, /* hex decode what we read */
        READ_FULL_FILE_WARN_WORLD_READABLE = 1 << 3, /* if regular file, log at LOG_WARNING level if access mode above 0700 */
        READ_FULL_FILE_CONNECT_SOCKET      = 1 << 4, /* if socket inode, connect to it and read off it */
        READ_FULL_FILE_FAIL_WHEN_LARGER    = 1 << 5, /* fail loading if file is larger than specified size */
} ReadFullFileFlags;

int fdopen_unlocked(int fd, const char *options, FILE **ret);
int take_fdopen_unlocked(int *fd, const char *options, FILE **ret);
FILE* take_fdopen(int *fd, const char *options);
DIR* take_fdopendir(int *dfd);
FILE* open_memstream_unlocked(char **ptr, size_t *sizeloc);
FILE* fmemopen_unlocked(void *buf, size_t size, const char *mode);

int write_string_stream_ts(FILE *f, const char *line, WriteStringFileFlags flags, const struct timespec *ts);
static inline int write_string_stream(FILE *f, const char *line, WriteStringFileFlags flags) {
        return write_string_stream_ts(f, line, flags, NULL);
}
int write_string_file_ts_at(int dir_fd, const char *fn, const char *line, WriteStringFileFlags flags, const struct timespec *ts);
static inline int write_string_file_ts(const char *fn, const char *line, WriteStringFileFlags flags, const struct timespec *ts) {
        return write_string_file_ts_at(AT_FDCWD, fn, line, flags, ts);
}
static inline int write_string_file_at(int dir_fd, const char *fn, const char *line, WriteStringFileFlags flags) {
        return write_string_file_ts_at(dir_fd, fn, line, flags, NULL);
}
static inline int write_string_file(const char *fn, const char *line, WriteStringFileFlags flags) {
        return write_string_file_ts(fn, line, flags, NULL);
}

int write_string_filef(const char *fn, WriteStringFileFlags flags, const char *format, ...) _printf_(3, 4);

int read_one_line_file_at(int dir_fd, const char *filename, char **ret);
static inline int read_one_line_file(const char *filename, char **ret) {
        return read_one_line_file_at(AT_FDCWD, filename, ret);
}
int read_full_file_full(int dir_fd, const char *filename, uint64_t offset, size_t size, ReadFullFileFlags flags, const char *bind_name, char **ret_contents, size_t *ret_size);
static inline int read_full_file_at(int dir_fd, const char *filename, char **ret_contents, size_t *ret_size) {
        return read_full_file_full(dir_fd, filename, UINT64_MAX, SIZE_MAX, 0, NULL, ret_contents, ret_size);
}
static inline int read_full_file(const char *filename, char **ret_contents, size_t *ret_size) {
        return read_full_file_full(AT_FDCWD, filename, UINT64_MAX, SIZE_MAX, 0, NULL, ret_contents, ret_size);
}

int read_virtual_file_fd(int fd, size_t max_size, char **ret_contents, size_t *ret_size);
int read_virtual_file_at(int dir_fd, const char *filename, size_t max_size, char **ret_contents, size_t *ret_size);
static inline int read_virtual_file(const char *filename, size_t max_size, char **ret_contents, size_t *ret_size) {
        return read_virtual_file_at(AT_FDCWD, filename, max_size, ret_contents, ret_size);
}
static inline int read_full_virtual_file(const char *filename, char **ret_contents, size_t *ret_size) {
        return read_virtual_file(filename, SIZE_MAX, ret_contents, ret_size);
}

int read_full_stream_full(FILE *f, const char *filename, uint64_t offset, size_t size, ReadFullFileFlags flags, char **ret_contents, size_t *ret_size);
static inline int read_full_stream(FILE *f, char **ret_contents, size_t *ret_size) {
        return read_full_stream_full(f, NULL, UINT64_MAX, SIZE_MAX, 0, ret_contents, ret_size);
}

int verify_file_at(int dir_fd, const char *fn, const char *blob, bool accept_extra_nl);
static inline int verify_file(const char *fn, const char *blob, bool accept_extra_nl) {
        return verify_file_at(AT_FDCWD, fn, blob, accept_extra_nl);
}

int executable_is_script(const char *path, char **interpreter);

int get_proc_field(const char *filename, const char *pattern, const char *terminator, char **field);

DIR *xopendirat(int dirfd, const char *name, int flags);

typedef enum XfopenFlags {
        XFOPEN_UNLOCKED = 1 << 0, /* call __fsetlocking(FSETLOCKING_BYCALLER) after opened */
        XFOPEN_SOCKET   = 1 << 1, /* also try to open unix socket */
} XfopenFlags;

int xfopenat_full(
                int dir_fd,
                const char *path,
                const char *mode,
                int open_flags,
                XfopenFlags flags,
                const char *bind_name,
                FILE **ret);
static inline int xfopenat(int dir_fd, const char *path, const char *mode, int open_flags, FILE **ret) {
        return xfopenat_full(dir_fd, path, mode, open_flags, 0, NULL, ret);
}
static inline int fopen_unlocked_at(int dir_fd, const char *path, const char *mode, int open_flags, FILE **ret) {
        return xfopenat_full(dir_fd, path, mode, open_flags, XFOPEN_UNLOCKED, NULL, ret);
}
static inline int fopen_unlocked(const char *path, const char *mode, FILE **ret) {
        return fopen_unlocked_at(AT_FDCWD, path, mode, 0, ret);
}

int fdopen_independent(int fd, const char *mode, FILE **ret);

int search_and_open(const char *path, int mode, const char *root, char **search, int *ret_fd, char **ret_path);
static inline int search_and_access(const char *path, int mode, const char *root, char**search, char **ret_path) {
        return search_and_open(path, mode, root, search, NULL, ret_path);
}
int search_and_fopen(const char *path, const char *mode, const char *root, const char **search, FILE **ret_file, char **ret_path);
int search_and_fopen_nulstr(const char *path, const char *mode, const char *root, const char *search, FILE **ret_file, char **ret_path);

int fflush_and_check(FILE *f);
int fflush_sync_and_check(FILE *f);

int write_timestamp_file_atomic(const char *fn, usec_t n);
int read_timestamp_file(const char *fn, usec_t *ret);

int fputs_with_separator(FILE *f, const char *s, const char *separator, bool *space);

typedef enum ReadLineFlags {
        READ_LINE_ONLY_NUL  = 1 << 0,
        READ_LINE_IS_A_TTY  = 1 << 1,
        READ_LINE_NOT_A_TTY = 1 << 2,
} ReadLineFlags;

int read_line_full(FILE *f, size_t limit, ReadLineFlags flags, char **ret);

static inline bool file_offset_beyond_memory_size(off_t x) {
        if (x < 0) /* off_t is signed, filter that out */
                return false;
        return (uint64_t) x > (uint64_t) SIZE_MAX;
}

static inline int read_line(FILE *f, size_t limit, char **ret) {
        return read_line_full(f, limit, 0, ret);
}

static inline int read_nul_string(FILE *f, size_t limit, char **ret) {
        return read_line_full(f, limit, READ_LINE_ONLY_NUL, ret);
}

int read_stripped_line(FILE *f, size_t limit, char **ret);

int safe_fgetc(FILE *f, char *ret);

int warn_file_is_world_accessible(const char *filename, struct stat *st, const char *unit, unsigned line);

int fopen_mode_to_flags(const char *mode);