src/basic/fileio.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 #include <dirent.h>
   5 #include <stdbool.h>
   6 #include <stddef.h>
   7 #include <stdio.h>
   8 #include <sys/stat.h>
   9 #include <sys/types.h>
  10
  11 #include "macro.h"
  12 #include "time-util.h"
  13
  14 #define LONG_LINE_MAX (1U*1024U*1024U)
  15
  16 typedef enum {
  17         WRITE_STRING_FILE_CREATE            = 1 << 0,
  18         WRITE_STRING_FILE_ATOMIC            = 1 << 1,
  19         WRITE_STRING_FILE_AVOID_NEWLINE     = 1 << 2,
  20         WRITE_STRING_FILE_VERIFY_ON_FAILURE = 1 << 3,
  21         WRITE_STRING_FILE_SYNC              = 1 << 4,
  22         WRITE_STRING_FILE_DISABLE_BUFFER    = 1 << 5,
  23         WRITE_STRING_FILE_NOFOLLOW          = 1 << 6,
  24
  25         /* And before you wonder, why write_string_file_atomic_label_ts() is a separate function instead of just one
  26            more flag here: it's about linking: we don't want to pull -lselinux into all users of write_string_file()
  27            and friends. */
  28
  29 } WriteStringFileFlags;
  30
  31 typedef enum {
  32         READ_FULL_FILE_SECURE   = 1 << 0,
  33         READ_FULL_FILE_UNBASE64 = 1 << 1,
  34 } ReadFullFileFlags;
  35
  36 int write_string_stream_ts(FILE *f, const char *line, WriteStringFileFlags flags, struct timespec *ts);
  37 static inline int write_string_stream(FILE *f, const char *line, WriteStringFileFlags flags) {
  38         return write_string_stream_ts(f, line, flags, NULL);
  39 }
  40 int write_string_file_ts(const char *fn, const char *line, WriteStringFileFlags flags, struct timespec *ts);
  41 static inline int write_string_file(const char *fn, const char *line, WriteStringFileFlags flags) {
  42         return write_string_file_ts(fn, line, flags, NULL);
  43 }
  44
  45 int write_string_filef(const char *fn, WriteStringFileFlags flags, const char *format, ...) _printf_(3, 4);
  46
  47 int read_one_line_file(const char *filename, char **line);
  48 int read_full_file_full(const char *filename, ReadFullFileFlags flags, char **contents, size_t *size);
  49 static inline int read_full_file(const char *filename, char **contents, size_t *size) {
  50         return read_full_file_full(filename, 0, contents, size);
  51 }
  52 int read_full_stream_full(FILE *f, const char *filename, ReadFullFileFlags flags, char **contents, size_t *size);
  53 static inline int read_full_stream(FILE *f, char **contents, size_t *size) {
  54         return read_full_stream_full(f, NULL, 0, contents, size);
  55 }
  56
  57 int verify_file(const char *fn, const char *blob, bool accept_extra_nl);
  58
  59 int executable_is_script(const char *path, char **interpreter);
  60
  61 int get_proc_field(const char *filename, const char *pattern, const char *terminator, char **field);
  62
  63 DIR *xopendirat(int dirfd, const char *name, int flags);
  64
  65 int search_and_fopen(const char *path, const char *mode, const char *root, const char **search, FILE **_f);
  66 int search_and_fopen_nulstr(const char *path, const char *mode, const char *root, const char *search, FILE **_f);
  67
  68 int fflush_and_check(FILE *f);
  69 int fflush_sync_and_check(FILE *f);
  70
  71 int write_timestamp_file_atomic(const char *fn, usec_t n);
  72 int read_timestamp_file(const char *fn, usec_t *ret);
  73
  74 int fputs_with_space(FILE *f, const char *s, const char *separator, bool *space);
  75
  76 typedef enum ReadLineFlags {
  77         READ_LINE_ONLY_NUL = 1 << 0,
  78 } ReadLineFlags;
  79
  80 int read_line_full(FILE *f, size_t limit, ReadLineFlags flags, char **ret);
  81
  82 static inline int read_line(FILE *f, size_t limit, char **ret) {
  83         return read_line_full(f, limit, 0, ret);
  84 }
  85
  86 static inline int read_nul_string(FILE *f, size_t limit, char **ret) {
  87         return read_line_full(f, limit, READ_LINE_ONLY_NUL, ret);
  88 }
  89
  90 int safe_fgetc(FILE *f, char *ret);
  91
  92 int warn_file_is_world_accessible(const char *filename, struct stat *st, const char *unit, unsigned line);