2 This file is part of GNUnet.
3 (C) 2001, 2002, 2003, 2004, 2005, 2006, 2009 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
25 #ifndef GNUNET_DISK_LIB_H
26 #define GNUNET_DISK_LIB_H
29 * Opaque handle used to access files.
31 struct GNUNET_DISK_FileHandle;
34 * Opaque handle used to manage a pipe.
36 struct GNUNET_DISK_PipeHandle;
39 /* we need size_t, and since it can be both unsigned int
40 or unsigned long long, this IS platform dependent;
41 but "stdlib.h" should be portable 'enough' to be
42 unconditionally available... */
44 #include "gnunet_configuration_lib.h"
45 #include "gnunet_scheduler_lib.h"
50 #if 0 /* keep Emacsens' auto-indent happy */
56 /* Open the file for reading */
57 #define GNUNET_DISK_OPEN_READ 1
58 /* Open the file for writing */
59 #define GNUNET_DISK_OPEN_WRITE 2
60 /* Open the file for both reading and writing */
61 #define GNUNET_DISK_OPEN_READWRITE 3
62 /* Fail if file already exists */
63 #define GNUNET_DISK_OPEN_FAILIFEXISTS 4
64 /* Truncate file if it exists */
65 #define GNUNET_DISK_OPEN_TRUNCATE 8
66 /* Create file if it doesn't exist */
67 #define GNUNET_DISK_OPEN_CREATE 16
68 /* Append to the file */
69 #define GNUNET_DISK_OPEN_APPEND 32
71 #define GNUNET_DISK_MAP_READ 1
72 #define GNUNET_DISK_MAP_WRITE 2
73 #define GNUNET_DISK_MAP_READWRITE 3
75 #define GNUNET_DISK_PERM_USER_READ 1
76 #define GNUNET_DISK_PERM_USER_WRITE 2
77 #define GNUNET_DISK_PERM_USER_EXEC 4
78 #define GNUNET_DISK_PERM_GROUP_READ 8
79 #define GNUNET_DISK_PERM_GROUP_WRITE 16
80 #define GNUNET_DISK_PERM_GROUP_EXEC 32
81 #define GNUNET_DISK_PERM_OTHER_READ 64
82 #define GNUNET_DISK_PERM_OTHER_WRITE 128
83 #define GNUNET_DISK_PERM_OTHER_EXEC 256
93 * Get the number of blocks that are left on the partition that
94 * contains the given file (for normal users).
96 * @param part a file on the partition to check
97 * @return -1 on errors, otherwise the number of free blocks
99 long GNUNET_DISK_get_blocks_available (const char *part);
103 * Checks whether a handle is invalid
104 * @param h handle to check
105 * @return GNUNET_YES if invalid, GNUNET_NO if valid
107 int GNUNET_DISK_handle_invalid (const struct GNUNET_DISK_FileHandle *h);
111 * Check that fil corresponds to a filename
112 * (of a file that exists and that is not a directory).
114 * @returns GNUNET_YES if yes, GNUNET_NO if not a file, GNUNET_SYSERR if something
115 * else (will print an error message in that case, too).
117 int GNUNET_DISK_file_test (const char *fil);
121 * Move the read/write pointer in a file
122 * @param h handle of an open file
123 * @param offset position to move to
124 * @param whence specification to which position the offset parameter relates to
125 * @return the new position on success, GNUNET_SYSERR otherwise
128 GNUNET_DISK_file_seek (const struct GNUNET_DISK_FileHandle *h,
130 enum GNUNET_DISK_Seek whence);
134 * Get the size of the file (or directory)
135 * of the given file (in bytes).
137 * @param filename name of the file or directory
138 * @param size set to the size of the file (or,
139 * in the case of directories, the sum
140 * of all sizes of files in the directory)
141 * @param includeSymLinks should symbolic links be
144 * @return GNUNET_OK on success, GNUNET_SYSERR on error
146 int GNUNET_DISK_file_size (const char *filename,
148 int includeSymLinks);
154 * @param filename name of the file
155 * @param dev set to the device ID
156 * @param ino set to the inode ID
157 * @return GNUNET_OK on success
159 int GNUNET_DISK_file_get_identifiers (const char *filename,
165 * Create an (empty) temporary file on disk.
167 * @param template component to use for the name;
168 * does NOT contain "XXXXXX" or "/tmp/".
169 * @return NULL on error, otherwise name of fresh
170 * file on disk in directory for temporary files
173 GNUNET_DISK_mktemp (const char *t);
178 * @param fn file name to be opened
179 * @param flags opening flags, a combination of GNUNET_DISK_OPEN_xxx bit flags
180 * @param perm permissions for the newly created file
181 * @return IO handle on success, NULL on error
183 struct GNUNET_DISK_FileHandle *GNUNET_DISK_file_open (const char *fn, int flags, ...);
186 * Creates an interprocess channel
187 * @param blocking creates an asynchronous pipe if set to GNUNET_NO
188 * @return handle to the new pipe, NULL on error
190 struct GNUNET_DISK_PipeHandle *GNUNET_DISK_pipe (int blocking);
193 * Closes an interprocess channel
195 * @return GNUNET_OK on success, GNUNET_SYSERR otherwise
197 int GNUNET_DISK_pipe_close (struct GNUNET_DISK_PipeHandle *p);
200 * Close an open file.
202 * @param h file handle
203 * @return GNUNET_OK on success, GNUNET_SYSERR otherwise
205 int GNUNET_DISK_file_close (struct GNUNET_DISK_FileHandle *h);
208 * Get the handle to a particular pipe end
210 * @param n number of the end
212 const struct GNUNET_DISK_FileHandle *GNUNET_DISK_pipe_handle (const struct
213 GNUNET_DISK_PipeHandle
217 * Read the contents of a binary file into a buffer.
218 * @param h handle to an open file
219 * @param result the buffer to write the result to
220 * @param len the maximum number of bytes to read
221 * @return the number of bytes read on success, GNUNET_SYSERR on failure
223 ssize_t GNUNET_DISK_file_read (const struct GNUNET_DISK_FileHandle *h, void *result,
228 * Read the contents of a binary file into a buffer.
229 * @param fn file name
230 * @param result the buffer to write the result to
231 * @param len the maximum number of bytes to read
232 * @return number of bytes read, GNUNET_SYSERR on failure
234 ssize_t GNUNET_DISK_fn_read (const char * const fn, void *result,
239 * Write a buffer to a file.
241 * @param h handle to open file
242 * @param buffer the data to write
243 * @param n number of bytes to write
244 * @return GNUNET_OK on success, GNUNET_SYSERR on error
246 ssize_t GNUNET_DISK_file_write (const struct GNUNET_DISK_FileHandle *h,
252 * Write a buffer to a file. If the file is longer than
253 * the given buffer size, it will be truncated.
255 * @param fn file name
256 * @param buffer the data to write
257 * @param n number of bytes to write
258 * @return number of bytes written on success, GNUNET_SYSERR on error
260 ssize_t GNUNET_DISK_fn_write (const char * fn,
268 * @return GNUNET_OK on success, GNUNET_SYSERR on error
270 int GNUNET_DISK_file_copy (const char *src, const char *dst);
274 * Scan a directory for files. The name of the directory
275 * must be expanded first (!).
277 * @param dirName the name of the directory
278 * @param callback the method to call for each file
279 * @param data argument to pass to callback
280 * @return the number of files found, -1 on error
282 int GNUNET_DISK_directory_scan (const char *dirName,
283 GNUNET_FileNameCallback callback,
288 * Opaque handle used for iterating over a directory.
290 struct GNUNET_DISK_DirectoryIterator;
294 * Function called to iterate over a directory.
297 * @param di argument to pass to "GNUNET_DISK_directory_iterator_next" to
298 * get called on the next entry (or finish cleanly)
299 * @param filename complete filename (absolute path)
300 * @param dirname directory name (absolute path)
302 typedef void (*GNUNET_DISK_DirectoryIteratorCallback) (void *cls,
304 GNUNET_DISK_DirectoryIterator
306 const char *filename,
307 const char *dirname);
311 * This function must be called during the DiskIteratorCallback
312 * (exactly once) to schedule the task to process the next
313 * filename in the directory (if there is one).
315 * @param iter opaque handle for the iterator
316 * @param can set to GNUNET_YES to terminate the iteration early
317 * @return GNUNET_YES if iteration will continue,
318 * GNUNET_NO if this was the last entry (and iteration is complete),
319 * GNUNET_SYSERR if "can" was YES
321 int GNUNET_DISK_directory_iterator_next (struct GNUNET_DISK_DirectoryIterator
326 * Scan a directory for files using the scheduler to run a task for
327 * each entry. The name of the directory must be expanded first (!).
328 * If a scheduler does not need to be used, GNUNET_DISK_directory_scan
329 * may provide a simpler API.
331 * @param sched scheduler to use
332 * @param prio priority to use
333 * @param dirName the name of the directory
334 * @param callback the method to call for each file
335 * @param callback_cls closure for callback
337 void GNUNET_DISK_directory_iterator_start (struct GNUNET_SCHEDULER_Handle
339 enum GNUNET_SCHEDULER_Priority
340 prio, const char *dirName,
341 GNUNET_DISK_DirectoryIteratorCallback
342 callback, void *callback_cls);
346 * Create the directory structure for storing
349 * @param filename name of a file in the directory
350 * @returns GNUNET_OK on success, GNUNET_SYSERR on failure,
351 * GNUNET_NO if directory exists but is not writeable
353 int GNUNET_DISK_directory_create_for_file (const char *filename);
357 * Test if fil is a directory that can be accessed.
358 * Will not print an error message if the directory
359 * does not exist. Will log errors if GNUNET_SYSERR is
362 * @return GNUNET_YES if yes, GNUNET_NO if does not exist, GNUNET_SYSERR
363 * on any error and if exists but not directory
365 int GNUNET_DISK_directory_test (const char *fil);
369 * Remove all files in a directory (rm -rf). Call with
372 * @param fileName the file to remove
373 * @return GNUNET_OK on success, GNUNET_SYSERR on error
375 int GNUNET_DISK_directory_remove (const char *fileName);
379 * Implementation of "mkdir -p"
381 * @param dir the directory to create
382 * @returns GNUNET_SYSERR on failure, GNUNET_OK otherwise
384 int GNUNET_DISK_directory_create (const char *dir);
388 * Lock a part of a file
389 * @param fh file handle
390 * @lockStart absolute position from where to lock
391 * @lockEnd absolute position until where to lock
392 * @excl GNUNET_YES for an exclusive lock
393 * @return GNUNET_OK on success, GNUNET_SYSERR on error
396 GNUNET_DISK_file_lock (struct GNUNET_DISK_FileHandle *fh, off_t lockStart,
397 off_t lockEnd, int excl);
400 * Unlock a part of a file
401 * @param fh file handle
402 * @lockStart absolute position from where to unlock
403 * @lockEnd absolute position until where to unlock
404 * @return GNUNET_OK on success, GNUNET_SYSERR on error
407 GNUNET_DISK_file_unlock (struct GNUNET_DISK_FileHandle *fh, off_t unlockStart,
412 * @brief Removes special characters as ':' from a filename.
413 * @param fn the filename to canonicalize
415 void GNUNET_DISK_filename_canonicalize (char *fn);
419 * @brief Change owner of a file
420 * @param filename file to change
421 * @param user new owner of the file
422 * @return GNUNET_OK on success, GNUNET_SYSERR on failure
424 int GNUNET_DISK_file_change_owner (const char *filename, const char *user);
428 * Construct full path to a file inside of the private
429 * directory used by GNUnet. Also creates the corresponding
430 * directory. If the resulting name is supposed to be
431 * a directory, end the last argument in '/' (or pass
432 * DIR_SEPARATOR_STR as the last argument before NULL).
434 * @param serviceName name of the service asking
435 * @param varargs is NULL-terminated list of
436 * path components to append to the
437 * private directory name.
438 * @return the constructed filename
440 char *GNUNET_DISK_get_home_filename (const struct GNUNET_CONFIGURATION_Handle *cfg,
441 const char *serviceName, ...);
445 * Opaque handle for a memory-mapping operation.
447 struct GNUNET_DISK_MapHandle;
450 * Map a file into memory
451 * @param h open file handle
452 * @param m handle to the new mapping (will be set)
453 * @param access access specification, GNUNET_DISK_MAP_xxx
454 * @param len size of the mapping
455 * @return pointer to the mapped memory region, NULL on failure
457 void *GNUNET_DISK_file_map (const struct GNUNET_DISK_FileHandle *h,
458 struct GNUNET_DISK_MapHandle **m,
459 int access, size_t len);
464 * @param h mapping handle
465 * @return GNUNET_OK on success, GNUNET_SYSERR otherwise
467 int GNUNET_DISK_file_unmap (struct GNUNET_DISK_MapHandle *h);
470 * Write file changes to disk
471 * @param h handle to an open file
472 * @return GNUNET_OK on success, GNUNET_SYSERR otherwise
474 int GNUNET_DISK_file_sync (const struct GNUNET_DISK_FileHandle *h);
476 #if 0 /* keep Emacsens' auto-indent happy */
484 /* ifndef GNUNET_DISK_LIB_H */
486 /* end of gnunet_disk_lib.h */