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,
60 GNUNET_DISK_PERM_NONE);
61 h = GNUNET_malloc (sizeof (struct GNUNET_BIO_ReadHandle) + BIO_BUFFER_SIZE);
62 h->buffer = (char *) &h[1];
63 h->size = BIO_BUFFER_SIZE;
70 * Close an open file. Reports if any errors reading
71 * from the file were encountered.
73 * @param h file handle
74 * @param emsg set to the error message
75 * @return GNUNET_OK on success, GNUNET_SYSERR otherwise
78 GNUNET_BIO_read_close (struct GNUNET_BIO_ReadHandle *h, char **emsg)
81 GNUNET_DISK_file_close (h->fd);
83 return (NULL == *emsg) ? GNUNET_OK : GNUNET_SYSERR;
88 * Read the contents of a binary file into a buffer.
90 * @param h handle to an open file
91 * @param what describes what is being read (for error message creation)
92 * @param result the buffer to write the result to
93 * @param len the number of bytes to read
94 * @return GNUNET_OK on success, GNUNET_SYSERR on failure
97 GNUNET_BIO_read (struct GNUNET_BIO_ReadHandle *h,
98 const char *what, void *result, size_t len)
106 return GNUNET_SYSERR;
110 /* first, use buffer */
111 min = h->have - h->pos;
116 memcpy (&dst[pos], &h->buffer[h->pos], min);
121 return GNUNET_OK; /* done! */
122 GNUNET_assert (h->have == h->pos);
124 ret = GNUNET_DISK_file_read (h->fd, h->buffer, h->size);
127 GNUNET_asprintf (&h->emsg,
128 _("Error reading `%s': %s"),
129 what, STRERROR (errno));
130 return GNUNET_SYSERR;
134 GNUNET_asprintf (&h->emsg,
135 _("Error reading `%s': %s"),
136 what, _("End of file"));
137 return GNUNET_SYSERR;
142 while (pos < len); /* should always be true */
148 * Read 0-terminated string from a file.
150 * @param h handle to an open file
151 * @param what describes what is being read (for error message creation)
152 * @param result the buffer to store a pointer to the (allocated) string to
153 * (note that *result could be set to NULL as well)
154 * @param maxLen maximum allowed length for the string
155 * @return GNUNET_OK on success, GNUNET_SYSERR on failure
158 GNUNET_BIO_read_string (struct GNUNET_BIO_ReadHandle *h,
159 const char *what, char **result, size_t maxLen)
164 if (GNUNET_OK != GNUNET_BIO_read_int32 (h, &big))
165 return GNUNET_SYSERR;
173 GNUNET_asprintf (&h->emsg,
174 _("String `%s' longer than allowed (%u > %u)"),
176 return GNUNET_SYSERR;
178 buf = GNUNET_malloc (big);
182 if (GNUNET_OK != GNUNET_BIO_read (h, what, buf, big))
185 return GNUNET_SYSERR;
193 * Read metadata container from a file.
195 * @param h handle to an open file
196 * @param what describes what is being read (for error message creation)
197 * @param result the buffer to store a pointer to the (allocated) metadata
198 * @return GNUNET_OK on success, GNUNET_SYSERR on failure
201 GNUNET_BIO_read_meta_data (struct GNUNET_BIO_ReadHandle *h,
203 struct GNUNET_CONTAINER_MetaData **result)
207 struct GNUNET_CONTAINER_MetaData *meta;
209 if (GNUNET_BIO_read_int32__ (h, what, (int32_t *) & size) != GNUNET_OK)
210 return GNUNET_SYSERR;
211 if (size > MAX_META_DATA)
213 GNUNET_asprintf (&h->emsg,
215 ("Serialized metadata `%s' larger than allowed (%u > %u)"),
216 what, size, MAX_META_DATA);
217 return GNUNET_SYSERR;
219 buf = GNUNET_malloc (size);
220 if (GNUNET_OK != GNUNET_BIO_read (h, what, buf, size))
223 return GNUNET_SYSERR;
225 meta = GNUNET_CONTAINER_meta_data_deserialize (buf, size);
229 GNUNET_asprintf (&h->emsg,
230 _("Metadata `%s' failed to deserialize"), what);
231 return GNUNET_SYSERR;
240 * Read an (u)int32_t.
242 * @param h hande to open file
243 * @param what describes what is being read (for error message creation)
244 * @param i address of 32-bit integer to read
245 * @return GNUNET_OK on success, GNUNET_SYSERR on error
248 GNUNET_BIO_read_int32__ (struct GNUNET_BIO_ReadHandle *h,
249 const char *what, int32_t * i)
253 if (GNUNET_OK != GNUNET_BIO_read (h, what, &big, sizeof (int32_t)))
254 return GNUNET_SYSERR;
261 * Read an (u)int64_t.
263 * @param h hande to open file
264 * @param what describes what is being read (for error message creation)
265 * @param i address of 64-bit integer to read
266 * @return GNUNET_OK on success, GNUNET_SYSERR on error
269 GNUNET_BIO_read_int64__ (struct GNUNET_BIO_ReadHandle *h,
270 const char *what, int64_t * i)
274 if (GNUNET_OK != GNUNET_BIO_read (h, what, &big, sizeof (int64_t)))
275 return GNUNET_SYSERR;
276 *i = GNUNET_ntohll (big);
282 * Handle for buffered writing.
284 struct GNUNET_BIO_WriteHandle
286 struct GNUNET_DISK_FileHandle *fd;
294 * Open a file for writing.
296 * @param fn file name to be opened
297 * @return IO handle on success, NULL on error
299 struct GNUNET_BIO_WriteHandle *
300 GNUNET_BIO_write_open (const char *fn)
302 struct GNUNET_DISK_FileHandle *fd;
303 struct GNUNET_BIO_WriteHandle *h;
305 fd = GNUNET_DISK_file_open (fn,
306 GNUNET_DISK_OPEN_WRITE |
307 GNUNET_DISK_OPEN_TRUNCATE |
308 GNUNET_DISK_OPEN_CREATE,
309 GNUNET_DISK_PERM_USER_READ |
310 GNUNET_DISK_PERM_USER_WRITE);
312 GNUNET_malloc (sizeof (struct GNUNET_BIO_WriteHandle) + BIO_BUFFER_SIZE);
313 h->buffer = (char *) &h[1];
314 h->size = BIO_BUFFER_SIZE;
322 * Close an open file for writing.
324 * @param h file handle
325 * @return GNUNET_OK on success, GNUNET_SYSERR otherwise
328 GNUNET_BIO_write_close (struct GNUNET_BIO_WriteHandle *h)
339 wrt = GNUNET_DISK_file_write (h->fd, h->buffer, h->have);
344 GNUNET_DISK_file_close (h->fd);
352 * Write a buffer to a file.
354 * @param h handle to open file
355 * @param buffer the data to write
356 * @param n number of bytes to write
357 * @return GNUNET_OK on success, GNUNET_SYSERR on error
360 GNUNET_BIO_write (struct GNUNET_BIO_WriteHandle *h,
361 const void *buffer, size_t n)
363 const char *src = buffer;
369 return GNUNET_SYSERR;
373 /* first, just use buffer */
374 min = h->size - h->have;
377 memcpy (&h->buffer[h->have], &src[pos], min);
381 return GNUNET_OK; /* done */
382 GNUNET_assert (h->have == h->size);
383 ret = GNUNET_DISK_file_write (h->fd, h->buffer, h->size);
386 GNUNET_DISK_file_close (h->fd);
388 return GNUNET_SYSERR; /* error */
392 while (pos < n); /* should always be true */
398 * Write a string to a file.
400 * @param h handle to open file
401 * @param s string to write (can be NULL)
402 * @return GNUNET_OK on success, GNUNET_SYSERR on error
405 GNUNET_BIO_write_string (struct GNUNET_BIO_WriteHandle *h, const char *s)
409 slen = (uint32_t) ((s == NULL) ? 0 : strlen (s) + 1);
410 if (GNUNET_OK != GNUNET_BIO_write_int32 (h, slen))
411 return GNUNET_SYSERR;
413 return GNUNET_BIO_write (h, s, slen - 1);
419 * Write metadata container to a file.
421 * @param h handle to open file
422 * @param m metadata to write
423 * @return GNUNET_OK on success, GNUNET_SYSERR on error
426 GNUNET_BIO_write_meta_data (struct GNUNET_BIO_WriteHandle *h,
427 const struct GNUNET_CONTAINER_MetaData *m)
432 size = GNUNET_CONTAINER_meta_data_get_serialized_size (m,
433 GNUNET_CONTAINER_META_DATA_SERIALIZE_FULL
435 GNUNET_CONTAINER_META_DATA_SERIALIZE_NO_COMPRESS);
436 if (size > MAX_META_DATA)
437 size = MAX_META_DATA;
438 buf = GNUNET_malloc (size);
439 GNUNET_CONTAINER_meta_data_serialize (m,
442 GNUNET_CONTAINER_META_DATA_SERIALIZE_PART
444 GNUNET_CONTAINER_META_DATA_SERIALIZE_NO_COMPRESS);
445 if ((GNUNET_OK != GNUNET_BIO_write_int32 (h, size))
446 || (GNUNET_OK != GNUNET_BIO_write (h, buf, size)))
449 return GNUNET_SYSERR;
457 * Write an (u)int32_t.
459 * @param h hande to open file
460 * @param i address of 32-bit integer to write
461 * @return GNUNET_OK on success, GNUNET_SYSERR on error
464 GNUNET_BIO_write_int32 (struct GNUNET_BIO_WriteHandle *h, int32_t i)
468 return GNUNET_BIO_write (h, &big, sizeof (int32_t));
473 * Write an (u)int64_t.
475 * @param h hande to open file
476 * @param i address of 64-bit integer to write
477 * @return GNUNET_OK on success, GNUNET_SYSERR on error
480 GNUNET_BIO_write_int64 (struct GNUNET_BIO_WriteHandle *h, int64_t i)
483 big = GNUNET_htonll (i);
484 return GNUNET_BIO_write (h, &big, sizeof (int64_t));