2 This file is part of GNUnet.
3 (C) 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 * @brief functions for buffering IO
23 * @author Christian Grothoff
26 #include "gnunet_bio_lib.h"
27 #include "gnunet_disk_lib.h"
29 #define BIO_BUFFER_SIZE 65536
31 #define MAX_META_DATA (1024 * 1024)
34 * Handle for buffered reading.
36 struct GNUNET_BIO_ReadHandle
38 struct GNUNET_DISK_FileHandle *fd;
48 * Open a file for reading.
50 * @param fn file name to be opened
51 * @return IO handle on success, NULL on error
53 struct GNUNET_BIO_ReadHandle *
54 GNUNET_BIO_read_open (const char *fn)
56 struct GNUNET_DISK_FileHandle *fd;
57 struct GNUNET_BIO_ReadHandle *h;
59 fd = GNUNET_DISK_file_open (fn, GNUNET_DISK_OPEN_READ, GNUNET_DISK_PERM_NONE);
62 h = GNUNET_malloc (sizeof (struct GNUNET_BIO_ReadHandle) + BIO_BUFFER_SIZE);
63 h->buffer = (char *) &h[1];
64 h->size = BIO_BUFFER_SIZE;
71 * Close an open file. Reports if any errors reading
72 * from the file were encountered.
74 * @param h file handle
75 * @param emsg set to the error message
76 * @return GNUNET_OK on success, GNUNET_SYSERR otherwise
79 GNUNET_BIO_read_close (struct GNUNET_BIO_ReadHandle *h, char **emsg)
83 err = (NULL == h->emsg) ? GNUNET_OK : GNUNET_SYSERR;
87 GNUNET_free_non_null (h->emsg);
88 GNUNET_DISK_file_close (h->fd);
95 * Read the contents of a binary file into a buffer.
97 * @param h handle to an open file
98 * @param what describes what is being read (for error message creation)
99 * @param result the buffer to write the result to
100 * @param len the number of bytes to read
101 * @return GNUNET_OK on success, GNUNET_SYSERR on failure
104 GNUNET_BIO_read (struct GNUNET_BIO_ReadHandle *h,
105 const char *what, void *result, size_t len)
113 return GNUNET_SYSERR;
117 /* first, use buffer */
118 min = h->have - h->pos;
123 memcpy (&dst[pos], &h->buffer[h->pos], min);
128 return GNUNET_OK; /* done! */
129 GNUNET_assert (h->have == h->pos);
131 ret = GNUNET_DISK_file_read (h->fd, h->buffer, h->size);
134 GNUNET_asprintf (&h->emsg,
135 _("Error reading `%s': %s"), what, STRERROR (errno));
136 return GNUNET_SYSERR;
140 GNUNET_asprintf (&h->emsg,
141 _("Error reading `%s': %s"), what, _("End of file"));
142 return GNUNET_SYSERR;
147 while (pos < len); /* should always be true */
153 * Read the contents of a binary file into a buffer.
155 * @param h handle to an open file
156 * @param file name of the source file
157 * @param line line number in the source file
158 * @param result the buffer to write the result to
159 * @param len the number of bytes to read
160 * @return GNUNET_OK on success, GNUNET_SYSERR on failure
163 GNUNET_BIO_read_fn (struct GNUNET_BIO_ReadHandle *h,
164 const char *file, int line, void *result, size_t len)
168 GNUNET_snprintf (what, sizeof (what), "%s:%d", file, line);
169 return GNUNET_BIO_read (h, what, result, len);
174 * Read 0-terminated string from a file.
176 * @param h handle to an open file
177 * @param what describes what is being read (for error message creation)
178 * @param result the buffer to store a pointer to the (allocated) string to
179 * (note that *result could be set to NULL as well)
180 * @param maxLen maximum allowed length for the string
181 * @return GNUNET_OK on success, GNUNET_SYSERR on failure
184 GNUNET_BIO_read_string (struct GNUNET_BIO_ReadHandle *h,
185 const char *what, char **result, size_t maxLen)
190 if (GNUNET_OK != GNUNET_BIO_read_int32 (h, &big))
192 GNUNET_free_non_null (h->emsg);
193 GNUNET_asprintf (&h->emsg, _("Error reading length of string `%s'"), what);
194 return GNUNET_SYSERR;
203 GNUNET_asprintf (&h->emsg,
204 _("String `%s' longer than allowed (%u > %u)"),
206 return GNUNET_SYSERR;
208 buf = GNUNET_malloc (big);
213 if (GNUNET_OK != GNUNET_BIO_read (h, what, buf, big))
217 return GNUNET_SYSERR;
224 * Read metadata container from a file.
226 * @param h handle to an open file
227 * @param what describes what is being read (for error message creation)
228 * @param result the buffer to store a pointer to the (allocated) metadata
229 * @return GNUNET_OK on success, GNUNET_SYSERR on failure
232 GNUNET_BIO_read_meta_data (struct GNUNET_BIO_ReadHandle *h,
234 struct GNUNET_CONTAINER_MetaData **result)
238 struct GNUNET_CONTAINER_MetaData *meta;
240 if (GNUNET_BIO_read_int32 (h, (int32_t *) & size) != GNUNET_OK)
241 return GNUNET_SYSERR;
247 if (size > MAX_META_DATA)
249 GNUNET_asprintf (&h->emsg,
250 _("Serialized metadata `%s' larger than allowed (%u>%u)"),
251 what, size, MAX_META_DATA);
252 return GNUNET_SYSERR;
254 buf = GNUNET_malloc (size);
255 if (GNUNET_OK != GNUNET_BIO_read (h, what, buf, size))
258 return GNUNET_SYSERR;
260 meta = GNUNET_CONTAINER_meta_data_deserialize (buf, size);
264 GNUNET_asprintf (&h->emsg, _("Metadata `%s' failed to deserialize"), what);
265 return GNUNET_SYSERR;
274 * Read an (u)int32_t.
276 * @param h hande to open file
277 * @param file name of the source file
278 * @param line line number in the source file
279 * @param i address of 32-bit integer to read
280 * @return GNUNET_OK on success, GNUNET_SYSERR on error
283 GNUNET_BIO_read_int32__ (struct GNUNET_BIO_ReadHandle *h,
284 const char *file, int line, int32_t * i)
288 if (GNUNET_OK != GNUNET_BIO_read_fn (h, file, line, &big, sizeof (int32_t)))
289 return GNUNET_SYSERR;
296 * Read an (u)int64_t.
298 * @param h hande to open file
299 * @param file name of the source file
300 * @param line line number in the source file
301 * @param i address of 64-bit integer to read
302 * @return GNUNET_OK on success, GNUNET_SYSERR on error
305 GNUNET_BIO_read_int64__ (struct GNUNET_BIO_ReadHandle *h,
306 const char *file, int line, int64_t * i)
310 if (GNUNET_OK != GNUNET_BIO_read_fn (h, file, line, &big, sizeof (int64_t)))
311 return GNUNET_SYSERR;
312 *i = GNUNET_ntohll (big);
318 * Handle for buffered writing.
320 struct GNUNET_BIO_WriteHandle
322 struct GNUNET_DISK_FileHandle *fd;
330 * Open a file for writing.
332 * @param fn file name to be opened
333 * @return IO handle on success, NULL on error
335 struct GNUNET_BIO_WriteHandle *
336 GNUNET_BIO_write_open (const char *fn)
338 struct GNUNET_DISK_FileHandle *fd;
339 struct GNUNET_BIO_WriteHandle *h;
341 fd = GNUNET_DISK_file_open (fn,
342 GNUNET_DISK_OPEN_WRITE |
343 GNUNET_DISK_OPEN_TRUNCATE |
344 GNUNET_DISK_OPEN_CREATE,
345 GNUNET_DISK_PERM_USER_READ |
346 GNUNET_DISK_PERM_USER_WRITE);
349 h = GNUNET_malloc (sizeof (struct GNUNET_BIO_WriteHandle) + BIO_BUFFER_SIZE);
350 h->buffer = (char *) &h[1];
351 h->size = BIO_BUFFER_SIZE;
359 * Close an open file for writing.
361 * @param h file handle
362 * @return GNUNET_OK on success, GNUNET_SYSERR otherwise
365 GNUNET_BIO_write_close (struct GNUNET_BIO_WriteHandle *h)
376 wrt = GNUNET_DISK_file_write (h->fd, h->buffer, h->have);
381 GNUNET_DISK_file_close (h->fd);
389 * Write a buffer to a file.
391 * @param h handle to open file
392 * @param buffer the data to write
393 * @param n number of bytes to write
394 * @return GNUNET_OK on success, GNUNET_SYSERR on error
397 GNUNET_BIO_write (struct GNUNET_BIO_WriteHandle *h,
398 const void *buffer, size_t n)
400 const char *src = buffer;
406 return GNUNET_SYSERR;
410 /* first, just use buffer */
411 min = h->size - h->have;
414 memcpy (&h->buffer[h->have], &src[pos], min);
418 return GNUNET_OK; /* done */
419 GNUNET_assert (h->have == h->size);
420 ret = GNUNET_DISK_file_write (h->fd, h->buffer, h->size);
423 GNUNET_DISK_file_close (h->fd);
425 return GNUNET_SYSERR; /* error */
429 while (pos < n); /* should always be true */
436 * Write a string to a file.
438 * @param h handle to open file
439 * @param s string to write (can be NULL)
440 * @return GNUNET_OK on success, GNUNET_SYSERR on error
443 GNUNET_BIO_write_string (struct GNUNET_BIO_WriteHandle *h, const char *s)
447 slen = (uint32_t) ((s == NULL) ? 0 : strlen (s) + 1);
448 if (GNUNET_OK != GNUNET_BIO_write_int32 (h, slen))
449 return GNUNET_SYSERR;
451 return GNUNET_BIO_write (h, s, slen - 1);
457 * Write metadata container to a file.
459 * @param h handle to open file
460 * @param m metadata to write
461 * @return GNUNET_OK on success, GNUNET_SYSERR on error
464 GNUNET_BIO_write_meta_data (struct GNUNET_BIO_WriteHandle *h,
465 const struct GNUNET_CONTAINER_MetaData *m)
471 return GNUNET_BIO_write_int32 (h, 0);
473 size = GNUNET_CONTAINER_meta_data_serialize (m,
476 GNUNET_CONTAINER_META_DATA_SERIALIZE_PART);
480 return GNUNET_SYSERR;
482 if ((GNUNET_OK != GNUNET_BIO_write_int32 (h, (uint32_t) size)) ||
483 (GNUNET_OK != GNUNET_BIO_write (h, buf, size)))
486 return GNUNET_SYSERR;
494 * Write an (u)int32_t.
496 * @param h hande to open file
497 * @param i address of 32-bit integer to write
498 * @return GNUNET_OK on success, GNUNET_SYSERR on error
501 GNUNET_BIO_write_int32 (struct GNUNET_BIO_WriteHandle *h, int32_t i)
506 return GNUNET_BIO_write (h, &big, sizeof (int32_t));
511 * Write an (u)int64_t.
513 * @param h hande to open file
514 * @param i address of 64-bit integer to write
515 * @return GNUNET_OK on success, GNUNET_SYSERR on error
518 GNUNET_BIO_write_int64 (struct GNUNET_BIO_WriteHandle *h, int64_t i)
522 big = GNUNET_htonll (i);
523 return GNUNET_BIO_write (h, &big, sizeof (int64_t));