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);
63 h = GNUNET_malloc (sizeof (struct GNUNET_BIO_ReadHandle) + BIO_BUFFER_SIZE);
64 h->buffer = (char *) &h[1];
65 h->size = BIO_BUFFER_SIZE;
72 * Close an open file. Reports if any errors reading
73 * from the file were encountered.
75 * @param h file handle
76 * @param emsg set to the error message
77 * @return GNUNET_OK on success, GNUNET_SYSERR otherwise
80 GNUNET_BIO_read_close (struct GNUNET_BIO_ReadHandle *h, char **emsg)
84 err = (NULL == h->emsg) ? GNUNET_OK : GNUNET_SYSERR;
88 GNUNET_free_non_null (h->emsg);
89 GNUNET_DISK_file_close (h->fd);
96 * Read the contents of a binary file into a buffer.
98 * @param h handle to an open file
99 * @param what describes what is being read (for error message creation)
100 * @param result the buffer to write the result to
101 * @param len the number of bytes to read
102 * @return GNUNET_OK on success, GNUNET_SYSERR on failure
105 GNUNET_BIO_read (struct GNUNET_BIO_ReadHandle *h,
106 const char *what, void *result, size_t len)
114 return GNUNET_SYSERR;
118 /* first, use buffer */
119 min = h->have - h->pos;
124 memcpy (&dst[pos], &h->buffer[h->pos], min);
129 return GNUNET_OK; /* done! */
130 GNUNET_assert (h->have == h->pos);
132 ret = GNUNET_DISK_file_read (h->fd, h->buffer, h->size);
135 GNUNET_asprintf (&h->emsg,
136 _("Error reading `%s': %s"),
137 what, STRERROR (errno));
138 return GNUNET_SYSERR;
142 GNUNET_asprintf (&h->emsg,
143 _("Error reading `%s': %s"),
144 what, _("End of file"));
145 return GNUNET_SYSERR;
150 while (pos < len); /* should always be true */
156 * Read the contents of a binary file into a buffer.
158 * @param h handle to an open file
159 * @param file name of the source file
160 * @param line line number in the source file
161 * @param result the buffer to write the result to
162 * @param len the number of bytes to read
163 * @return GNUNET_OK on success, GNUNET_SYSERR on failure
165 int GNUNET_BIO_read_fn (struct GNUNET_BIO_ReadHandle *h,
166 const char *file, int line,
171 GNUNET_snprintf (what,
175 return GNUNET_BIO_read (h, what, result, len);
180 * Read 0-terminated string from a file.
182 * @param h handle to an open file
183 * @param what describes what is being read (for error message creation)
184 * @param result the buffer to store a pointer to the (allocated) string to
185 * (note that *result could be set to NULL as well)
186 * @param maxLen maximum allowed length for the string
187 * @return GNUNET_OK on success, GNUNET_SYSERR on failure
190 GNUNET_BIO_read_string (struct GNUNET_BIO_ReadHandle *h,
191 const char *what, char **result, size_t maxLen)
196 if (GNUNET_OK != GNUNET_BIO_read_int32 (h, &big))
198 GNUNET_free_non_null (h->emsg);
199 GNUNET_asprintf (&h->emsg,
200 _("Error reading length of string `%s'"),
202 return GNUNET_SYSERR;
211 GNUNET_asprintf (&h->emsg,
212 _("String `%s' longer than allowed (%u > %u)"),
214 return GNUNET_SYSERR;
216 buf = GNUNET_malloc (big);
221 if (GNUNET_OK != GNUNET_BIO_read (h, what, buf, big))
225 return GNUNET_SYSERR;
232 * Read metadata container from a file.
234 * @param h handle to an open file
235 * @param what describes what is being read (for error message creation)
236 * @param result the buffer to store a pointer to the (allocated) metadata
237 * @return GNUNET_OK on success, GNUNET_SYSERR on failure
240 GNUNET_BIO_read_meta_data (struct GNUNET_BIO_ReadHandle *h,
242 struct GNUNET_CONTAINER_MetaData **result)
246 struct GNUNET_CONTAINER_MetaData *meta;
248 if (GNUNET_BIO_read_int32 (h, (int32_t *) &size) != GNUNET_OK)
249 return GNUNET_SYSERR;
255 if (size > MAX_META_DATA)
257 GNUNET_asprintf (&h->emsg,
258 _("Serialized metadata `%s' larger than allowed (%u>%u)"),
259 what, size, MAX_META_DATA);
260 return GNUNET_SYSERR;
262 buf = GNUNET_malloc (size);
263 if (GNUNET_OK != GNUNET_BIO_read (h, what, buf, size))
266 return GNUNET_SYSERR;
268 meta = GNUNET_CONTAINER_meta_data_deserialize (buf, size);
272 GNUNET_asprintf (&h->emsg,
273 _("Metadata `%s' failed to deserialize"), what);
274 return GNUNET_SYSERR;
283 * Read an (u)int32_t.
285 * @param h hande to open file
286 * @param file name of the source file
287 * @param line line number in the source file
288 * @param i address of 32-bit integer to read
289 * @return GNUNET_OK on success, GNUNET_SYSERR on error
292 GNUNET_BIO_read_int32__ (struct GNUNET_BIO_ReadHandle *h,
299 if (GNUNET_OK != GNUNET_BIO_read_fn (h, file, line, &big, sizeof (int32_t)))
300 return GNUNET_SYSERR;
307 * Read an (u)int64_t.
309 * @param h hande to open file
310 * @param file name of the source file
311 * @param line line number in the source file
312 * @param i address of 64-bit integer to read
313 * @return GNUNET_OK on success, GNUNET_SYSERR on error
316 GNUNET_BIO_read_int64__ (struct GNUNET_BIO_ReadHandle *h,
323 if (GNUNET_OK != GNUNET_BIO_read_fn (h, file, line, &big, sizeof (int64_t)))
324 return GNUNET_SYSERR;
325 *i = GNUNET_ntohll (big);
331 * Handle for buffered writing.
333 struct GNUNET_BIO_WriteHandle
335 struct GNUNET_DISK_FileHandle *fd;
343 * Open a file for writing.
345 * @param fn file name to be opened
346 * @return IO handle on success, NULL on error
348 struct GNUNET_BIO_WriteHandle *
349 GNUNET_BIO_write_open (const char *fn)
351 struct GNUNET_DISK_FileHandle *fd;
352 struct GNUNET_BIO_WriteHandle *h;
354 fd = GNUNET_DISK_file_open (fn,
355 GNUNET_DISK_OPEN_WRITE |
356 GNUNET_DISK_OPEN_TRUNCATE |
357 GNUNET_DISK_OPEN_CREATE,
358 GNUNET_DISK_PERM_USER_READ |
359 GNUNET_DISK_PERM_USER_WRITE);
363 GNUNET_malloc (sizeof (struct GNUNET_BIO_WriteHandle) + BIO_BUFFER_SIZE);
364 h->buffer = (char *) &h[1];
365 h->size = BIO_BUFFER_SIZE;
373 * Close an open file for writing.
375 * @param h file handle
376 * @return GNUNET_OK on success, GNUNET_SYSERR otherwise
379 GNUNET_BIO_write_close (struct GNUNET_BIO_WriteHandle *h)
390 wrt = GNUNET_DISK_file_write (h->fd, h->buffer, h->have);
395 GNUNET_DISK_file_close (h->fd);
403 * Write a buffer to a file.
405 * @param h handle to open file
406 * @param buffer the data to write
407 * @param n number of bytes to write
408 * @return GNUNET_OK on success, GNUNET_SYSERR on error
411 GNUNET_BIO_write (struct GNUNET_BIO_WriteHandle *h,
412 const void *buffer, size_t n)
414 const char *src = buffer;
420 return GNUNET_SYSERR;
424 /* first, just use buffer */
425 min = h->size - h->have;
428 memcpy (&h->buffer[h->have], &src[pos], min);
432 return GNUNET_OK; /* done */
433 GNUNET_assert (h->have == h->size);
434 ret = GNUNET_DISK_file_write (h->fd, h->buffer, h->size);
437 GNUNET_DISK_file_close (h->fd);
439 return GNUNET_SYSERR; /* error */
443 while (pos < n); /* should always be true */
450 * Write a string to a file.
452 * @param h handle to open file
453 * @param s string to write (can be NULL)
454 * @return GNUNET_OK on success, GNUNET_SYSERR on error
457 GNUNET_BIO_write_string (struct GNUNET_BIO_WriteHandle *h, const char *s)
461 slen = (uint32_t) ((s == NULL) ? 0 : strlen (s) + 1);
462 if (GNUNET_OK != GNUNET_BIO_write_int32 (h, slen))
463 return GNUNET_SYSERR;
465 return GNUNET_BIO_write (h, s, slen - 1);
471 * Write metadata container to a file.
473 * @param h handle to open file
474 * @param m metadata to write
475 * @return GNUNET_OK on success, GNUNET_SYSERR on error
478 GNUNET_BIO_write_meta_data (struct GNUNET_BIO_WriteHandle *h,
479 const struct GNUNET_CONTAINER_MetaData *m)
485 return GNUNET_BIO_write_int32 (h, 0);
487 size = GNUNET_CONTAINER_meta_data_serialize (m,
490 GNUNET_CONTAINER_META_DATA_SERIALIZE_PART);
494 return GNUNET_SYSERR;
496 if ( (GNUNET_OK != GNUNET_BIO_write_int32 (h, (uint32_t) size)) ||
497 (GNUNET_OK != GNUNET_BIO_write (h, buf, size)) )
500 return GNUNET_SYSERR;
508 * Write an (u)int32_t.
510 * @param h hande to open file
511 * @param i address of 32-bit integer to write
512 * @return GNUNET_OK on success, GNUNET_SYSERR on error
515 GNUNET_BIO_write_int32 (struct GNUNET_BIO_WriteHandle *h, int32_t i)
519 return GNUNET_BIO_write (h, &big, sizeof (int32_t));
524 * Write an (u)int64_t.
526 * @param h hande to open file
527 * @param i address of 64-bit integer to write
528 * @return GNUNET_OK on success, GNUNET_SYSERR on error
531 GNUNET_BIO_write_int64 (struct GNUNET_BIO_WriteHandle *h, int64_t i)
534 big = GNUNET_htonll (i);
535 return GNUNET_BIO_write (h, &big, sizeof (int64_t));