2 This file is part of GNUnet.
3 (C) 2001, 2002, 2003, 2004, 2005, 2006 Christian Grothoff (and other contributing authors)
5 GNUnet is free software; you can redistribute it and/or modify
6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 2, or (at your
8 option) any later version.
10 GNUnet is distributed in the hope that it will be useful, but
11 WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 General Public License for more details.
15 You should have received a copy of the GNU General Public License
16 along with GNUnet; see the file COPYING. If not, write to the
17 Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA.
22 * @file include/gnunet_disk_lib.h
26 #ifndef GNUNET_DISK_LIB_H
27 #define GNUNET_DISK_LIB_H
29 #include "gnunet_configuration_lib.h"
30 #include "gnunet_scheduler_lib.h"
32 /* we need size_t, and since it can be both unsigned int
33 or unsigned long long, this IS platform dependent;
34 but "stdlib.h" should be portable 'enough' to be
35 unconditionally available... */
41 #if 0 /* keep Emacsens' auto-indent happy */
46 /* Open the file for reading */
47 #define GNUNET_DISK_OPEN_READ 1
48 /* Open the file for writing */
49 #define GNUNET_DISK_OPEN_WRITE 2
50 /* Open the file for both reading and writing */
51 #define GNUNET_DISK_OPEN_READWRITE 3
52 /* Fail if file already exists */
53 #define GNUNET_DISK_OPEN_FAILIFEXISTS 4
54 /* Truncate file if it exists */
55 #define GNUNET_DISK_OPEN_TRUNCATE 8
56 /* Create file if it doesn't exist */
57 #define GNUNET_DISK_OPEN_CREATE 16
58 /* Append to the file */
59 #define GNUNET_DISK_OPEN_APPEND 32
61 #define GNUNET_DISK_MAP_READ 1
62 #define GNUNET_DISK_MAP_WRITE 2
63 #define GNUNET_DISK_MAP_READWRITE 3
65 #define GNUNET_DISK_PERM_USER_READ 1
66 #define GNUNET_DISK_PERM_USER_WRITE 2
67 #define GNUNET_DISK_PERM_USER_EXEC 4
68 #define GNUNET_DISK_PERM_GROUP_READ 8
69 #define GNUNET_DISK_PERM_GROUP_WRITE 16
70 #define GNUNET_DISK_PERM_GROUP_EXEC 32
71 #define GNUNET_DISK_PERM_OTHER_READ 64
72 #define GNUNET_DISK_PERM_OTHER_WRITE 128
73 #define GNUNET_DISK_PERM_OTHER_EXEC 256
75 enum GNUNET_DISK_Seek {GNUNET_SEEK_SET, GNUNET_SEEK_CUR, GNUNET_SEEK_END};
77 struct GNUNET_DISK_FileHandle;
80 * Get the number of blocks that are left on the partition that
81 * contains the given file (for normal users).
83 * @param part a file on the partition to check
84 * @return -1 on errors, otherwise the number of free blocks
86 long GNUNET_DISK_get_blocks_available (const char *part);
90 * Checks whether a handle is invalid
91 * @param h handle to check
92 * @return GNUNET_YES if invalid, GNUNET_NO if valid
94 int GNUNET_DISK_handle_invalid (const struct GNUNET_DISK_FileHandle *h);
98 * Check that fil corresponds to a filename
99 * (of a file that exists and that is not a directory).
101 * @returns GNUNET_YES if yes, GNUNET_NO if not a file, GNUNET_SYSERR if something
102 * else (will print an error message in that case, too).
104 int GNUNET_DISK_file_test (const char *fil);
108 * Move the read/write pointer in a file
109 * @param h handle of an open file
110 * @param offset position to move to
111 * @param whence specification to which position the offset parameter relates to
112 * @return the new position on success, GNUNET_SYSERR otherwise
115 GNUNET_DISK_file_seek (const struct GNUNET_DISK_FileHandle *h, off_t offset,
116 enum GNUNET_DISK_Seek whence);
120 * Get the size of the file (or directory)
121 * of the given file (in bytes).
123 * @param includeSymLinks should symbolic links be
126 * @return GNUNET_OK on success, GNUNET_SYSERR on error
128 int GNUNET_DISK_file_size (const char *filename,
129 unsigned long long *size, int includeSymLinks);
134 * @param fn file name to be opened
135 * @param flags opening flags, a combination of GNUNET_DISK_OPEN_xxx bit flags
136 * @param perm permissions for the newly created file
137 * @return IO handle on success, NULL on error
139 struct GNUNET_DISK_FileHandle *GNUNET_DISK_file_open (const char *fn, int flags, ...);
143 * Close an open file.
145 * @param h file handle
146 * @return GNUNET_OK on success, GNUNET_SYSERR otherwise
148 int GNUNET_DISK_file_close (struct GNUNET_DISK_FileHandle *h);
152 * Read the contents of a binary file into a buffer.
153 * @param h handle to an open file
154 * @param result the buffer to write the result to
155 * @param len the maximum number of bytes to read
156 * @return the number of bytes read on success, GNUNET_SYSERR on failure
158 ssize_t GNUNET_DISK_file_read (const struct GNUNET_DISK_FileHandle *h, void *result,
163 * Read the contents of a binary file into a buffer.
164 * @param fn file name
165 * @param result the buffer to write the result to
166 * @param len the maximum number of bytes to read
167 * @return number of bytes read, GNUNET_SYSERR on failure
169 ssize_t GNUNET_DISK_fn_read (const char * const fn, void *result,
174 * Write a buffer to a file.
176 * @param h handle to open file
177 * @param buffer the data to write
178 * @param n number of bytes to write
179 * @return GNUNET_OK on success, GNUNET_SYSERR on error
181 ssize_t GNUNET_DISK_file_write (const struct GNUNET_DISK_FileHandle *h,
187 * Write a buffer to a file. If the file is longer than
188 * the given buffer size, it will be truncated.
190 * @param fn file name
191 * @param buffer the data to write
192 * @param n number of bytes to write
193 * @return number of bytes written on success, GNUNET_SYSERR on error
195 ssize_t GNUNET_DISK_fn_write (const char * fn,
203 * @return GNUNET_OK on success, GNUNET_SYSERR on error
205 int GNUNET_DISK_file_copy (const char *src, const char *dst);
209 * Scan a directory for files. The name of the directory
210 * must be expanded first (!).
212 * @param dirName the name of the directory
213 * @param callback the method to call for each file
214 * @param data argument to pass to callback
215 * @return the number of files found, -1 on error
217 int GNUNET_DISK_directory_scan (const char *dirName,
218 GNUNET_FileNameCallback callback, void *data);
222 * Opaque handle used for iterating over a directory.
224 struct GNUNET_DISK_DirectoryIterator;
228 * Function called to iterate over a directory.
231 * @param di argument to pass to "GNUNET_DISK_directory_iterator_next" to
232 * get called on the next entry (or finish cleanly)
233 * @param filename complete filename (absolute path)
234 * @param dirname directory name (absolute path)
236 typedef void (*GNUNET_DISK_DirectoryIteratorCallback) (void *cls,
238 GNUNET_DISK_DirectoryIterator
240 const char *filename,
241 const char *dirname);
245 * This function must be called during the DiskIteratorCallback
246 * (exactly once) to schedule the task to process the next
247 * filename in the directory (if there is one).
249 * @param iter opaque handle for the iterator
250 * @param can set to GNUNET_YES to terminate the iteration early
251 * @return GNUNET_YES if iteration will continue,
252 * GNUNET_NO if this was the last entry (and iteration is complete),
253 * GNUNET_SYSERR if "can" was YES
255 int GNUNET_DISK_directory_iterator_next (struct GNUNET_DISK_DirectoryIterator
260 * Scan a directory for files using the scheduler to run a task for
261 * each entry. The name of the directory must be expanded first (!).
262 * If a scheduler does not need to be used, GNUNET_DISK_directory_scan
263 * may provide a simpler API.
265 * @param sched scheduler to use
266 * @param prio priority to use
267 * @param dirName the name of the directory
268 * @param callback the method to call for each file
269 * @param callback_cls closure for callback
271 void GNUNET_DISK_directory_iterator_start (struct GNUNET_SCHEDULER_Handle
273 enum GNUNET_SCHEDULER_Priority
274 prio, const char *dirName,
275 GNUNET_DISK_DirectoryIteratorCallback
276 callback, void *callback_cls);
280 * Create the directory structure for storing
283 * @param filename name of a file in the directory
284 * @returns GNUNET_OK on success, GNUNET_SYSERR on failure,
285 * GNUNET_NO if directory exists but is not writeable
287 int GNUNET_DISK_directory_create_for_file (const char *filename);
291 * Test if fil is a directory that can be accessed.
292 * Will not print an error message if the directory
293 * does not exist. Will log errors if GNUNET_SYSERR is
296 * @return GNUNET_YES if yes, GNUNET_NO if does not exist, GNUNET_SYSERR
297 * on any error and if exists but not directory
299 int GNUNET_DISK_directory_test (const char *fil);
303 * Remove all files in a directory (rm -rf). Call with
306 * @param fileName the file to remove
307 * @return GNUNET_OK on success, GNUNET_SYSERR on error
309 int GNUNET_DISK_directory_remove (const char *fileName);
313 * Implementation of "mkdir -p"
315 * @param dir the directory to create
316 * @returns GNUNET_SYSERR on failure, GNUNET_OK otherwise
318 int GNUNET_DISK_directory_create (const char *dir);
322 * Lock a part of a file
323 * @param fh file handle
324 * @lockStart absolute position from where to lock
325 * @lockEnd absolute position until where to lock
326 * @return GNUNET_OK on success, GNUNET_SYSERR on error
329 GNUNET_DISK_file_lock(struct GNUNET_DISK_FileHandle *fh, off_t lockStart,
334 * @brief Removes special characters as ':' from a filename.
335 * @param fn the filename to canonicalize
337 void GNUNET_DISK_filename_canonicalize (char *fn);
341 * @brief Change owner of a file
342 * @param filename file to change
343 * @param user new owner of the file
344 * @return GNUNET_OK on success, GNUNET_SYSERR on failure
346 int GNUNET_DISK_file_change_owner (const char *filename, const char *user);
350 * Construct full path to a file inside of the private
351 * directory used by GNUnet. Also creates the corresponding
352 * directory. If the resulting name is supposed to be
353 * a directory, end the last argument in '/' (or pass
354 * DIR_SEPARATOR_STR as the last argument before NULL).
356 * @param serviceName name of the service asking
357 * @param varargs is NULL-terminated list of
358 * path components to append to the
359 * private directory name.
360 * @return the constructed filename
362 char *GNUNET_DISK_get_home_filename (const struct GNUNET_CONFIGURATION_Handle *cfg,
363 const char *serviceName, ...);
367 * Opaque handle for a memory-mapping operation.
369 struct GNUNET_DISK_MapHandle;
372 * Map a file into memory
373 * @param h open file handle
374 * @param m handle to the new mapping (will be set)
375 * @param access access specification, GNUNET_DISK_MAP_xxx
376 * @param len size of the mapping
377 * @return pointer to the mapped memory region, NULL on failure
379 void *GNUNET_DISK_file_map (const struct GNUNET_DISK_FileHandle *h,
380 struct GNUNET_DISK_MapHandle **m,
381 int access, size_t len);
386 * @param h mapping handle
387 * @return GNUNET_OK on success, GNUNET_SYSERR otherwise
389 int GNUNET_DISK_file_unmap (struct GNUNET_DISK_MapHandle *h);
392 * Write file changes to disk
393 * @param h handle to an open file
394 * @return GNUNET_OK on success, GNUNET_SYSERR otherwise
396 int GNUNET_DISK_file_sync (const struct GNUNET_DISK_FileHandle *h);
398 #if 0 /* keep Emacsens' auto-indent happy */
406 /* ifndef GNUNET_DISK_LIB_H */
408 /* end of gnunet_disk_lib.h */