src/lib/fs/files.h

   1 /* Copyright (c) 2003-2004, Roger Dingledine
   2  * Copyright (c) 2004-2006, Roger Dingledine, Nick Mathewson.
   3  * Copyright (c) 2007-2021, The Tor Project, Inc. */
   4 /* See LICENSE for licensing information */
   5
   6 /**
   7  * \file files.h
   8  *
   9  * \brief Header for files.c
  10  **/
  11
  12 #ifndef TOR_FS_H
  13 #define TOR_FS_H
  14
  15 #include "lib/cc/compat_compiler.h"
  16 #include "lib/cc/torint.h"
  17 #include "lib/testsupport/testsupport.h"
  18
  19 #include <stddef.h>
  20 #include <stdio.h>
  21
  22 #ifdef _WIN32
  23 /* We need these for struct stat to work */
  24 #ifdef HAVE_SYS_TYPES_H
  25 #include <sys/types.h>
  26 #endif
  27 #ifdef HAVE_SYS_STAT_H
  28 #include <sys/stat.h>
  29 #endif
  30 #endif /* defined(_WIN32) */
  31
  32 #ifndef O_BINARY
  33 #define O_BINARY 0
  34 #endif
  35 #ifndef O_TEXT
  36 #define O_TEXT 0
  37 #endif
  38 #ifndef O_NOFOLLOW
  39 #define O_NOFOLLOW 0
  40 #endif
  41
  42 struct stat;
  43
  44 int tor_open_cloexec(const char *path, int flags, unsigned mode);
  45 FILE *tor_fopen_cloexec(const char *path, const char *mode);
  46 int tor_rename(const char *path_old, const char *path_new);
  47
  48 int replace_file(const char *from, const char *to);
  49 int touch_file(const char *fname);
  50
  51 MOCK_DECL(int,tor_unlink,(const char *pathname));
  52
  53 /** Return values from file_status(); see that function's documentation
  54  * for details. */
  55 typedef enum { FN_ERROR, FN_NOENT, FN_FILE, FN_DIR, FN_EMPTY } file_status_t;
  56
  57 file_status_t file_status(const char *filename);
  58 bool is_file(file_status_t file_type);
  59 bool is_dir(file_status_t file_type);
  60
  61 int64_t tor_get_avail_disk_space(const char *path);
  62
  63 ssize_t write_all_to_fd(int fd, const char *buf, size_t count);
  64 ssize_t read_all_from_fd(int fd, char *buf, size_t count);
  65
  66 #define OPEN_FLAGS_REPLACE (O_WRONLY|O_CREAT|O_TRUNC)
  67 #define OPEN_FLAGS_APPEND (O_WRONLY|O_CREAT|O_APPEND)
  68 #define OPEN_FLAGS_DONT_REPLACE (O_CREAT|O_EXCL|O_APPEND|O_WRONLY)
  69 typedef struct open_file_t open_file_t;
  70 int start_writing_to_file(const char *fname, int open_flags, int mode,
  71                           open_file_t **data_out);
  72 FILE *start_writing_to_stdio_file(const char *fname, int open_flags, int mode,
  73                                   open_file_t **data_out);
  74 FILE *fdopen_file(open_file_t *file_data);
  75 int finish_writing_to_file(open_file_t *file_data);
  76 int abort_writing_to_file(open_file_t *file_data);
  77 MOCK_DECL(int, write_str_to_file,(const char *fname, const char *str,
  78                                   int bin));
  79 MOCK_DECL(int, write_bytes_to_file,(const char *fname, const char *str,
  80                                     size_t len,int bin));
  81
  82 /** An ad-hoc type to hold a string of characters and a count; used by
  83  * write_chunks_to_file. */
  84 typedef struct sized_chunk_t {
  85   const char *bytes;
  86   size_t len;
  87 } sized_chunk_t;
  88 struct smartlist_t;
  89 int write_chunks_to_file(const char *fname, const struct smartlist_t *chunks,
  90                          int bin, int no_tempfile);
  91 int append_bytes_to_file(const char *fname, const char *str, size_t len,
  92                          int bin);
  93 int write_bytes_to_new_file(const char *fname, const char *str, size_t len,
  94                             int bin);
  95
  96 int write_str_to_file_if_not_equal(const char *fname, const char *str);
  97
  98 /** Flag for read_file_to_str: open the file in binary mode. */
  99 #define RFTS_BIN            1
 100 /** Flag for read_file_to_str: it's okay if the file doesn't exist. */
 101 #define RFTS_IGNORE_MISSING 2
 102
 103 MOCK_DECL_ATTR(char *, read_file_to_str,(const char *filename, int flags,
 104                                          struct stat *stat_out),
 105                ATTR_MALLOC);
 106 char *read_file_to_str_until_eof(int fd, size_t max_bytes_to_read,
 107                                  size_t *sz_out)
 108   ATTR_MALLOC;
 109
 110 #if !defined(HAVE_GETDELIM) || defined(TOR_UNIT_TESTS)
 111 /** Internal back-end function to implement getdelim(): only exists when
 112  * Tor is built for unit tests, or when Tor is built on an operating system
 113  * without its own getdelim(). */
 114 ssize_t compat_getdelim_(char **lineptr, size_t *n, int delim, FILE *stream);
 115 #endif /* !defined(HAVE_GETDELIM) || defined(TOR_UNIT_TESTS) */
 116
 117 #ifdef HAVE_GETDELIM
 118 /**
 119  * Cross-platform wrapper for getdelim(): behaves as the POSIX-standard
 120  * getdelim() function.
 121  *
 122  * See `getdelim(3)` for more information.
 123  *
 124  * Note that this function will use the libc memory allocator -- so any memory
 125  * passed to this function must come from raw_malloc(), and must be freed by
 126  * raw_free() -- don't use tor_malloc() and tor_free() with this.
 127  */
 128 #define tor_getdelim(lineptr, n, delim, stream) \
 129   getdelim((lineptr), (n), (delim), (stream))
 130 #else /* !defined(HAVE_GETDELIM) */
 131 #define tor_getdelim(lineptr, n, delim, stream) \
 132   compat_getdelim_((lineptr), (n), (delim), (stream))
 133 #endif /* defined(HAVE_GETDELIM) */
 134
 135 #ifdef HAVE_GETLINE
 136 /**
 137  * Cross-platform wrapper for getline(): behaves as the POSIX-standard
 138  * getline() function.
 139  *
 140  * See tor_getdelim() for usage notes.
 141  */
 142 #define tor_getline(lineptr, n, stream) \
 143   getline((lineptr), (n), (stream))
 144 #else /* !defined(HAVE_GETLINE) */
 145 #define tor_getline(lineptr, n, stream) \
 146   tor_getdelim((lineptr), (n), '\n', (stream))
 147 #endif /* defined(HAVE_GETLINE) */
 148
 149 #endif /* !defined(TOR_FS_H) */