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)
83 GNUNET_DISK_file_close (h->fd);
85 return (NULL == *emsg) ? GNUNET_OK : GNUNET_SYSERR;
90 * Read the contents of a binary file into a buffer.
92 * @param h handle to an open file
93 * @param what describes what is being read (for error message creation)
94 * @param result the buffer to write the result to
95 * @param len the number of bytes to read
96 * @return GNUNET_OK on success, GNUNET_SYSERR on failure
99 GNUNET_BIO_read (struct GNUNET_BIO_ReadHandle *h,
100 const char *what, void *result, size_t len)
108 return GNUNET_SYSERR;
112 /* first, use buffer */
113 min = h->have - h->pos;
118 memcpy (&dst[pos], &h->buffer[h->pos], min);
123 return GNUNET_OK; /* done! */
124 GNUNET_assert (h->have == h->pos);
126 ret = GNUNET_DISK_file_read (h->fd, h->buffer, h->size);
129 GNUNET_asprintf (&h->emsg,
130 _("Error reading `%s': %s"),
131 what, STRERROR (errno));
133 return GNUNET_SYSERR;
137 GNUNET_asprintf (&h->emsg,
138 _("Error reading `%s': %s"),
139 what, _("End of file"));
141 return GNUNET_SYSERR;
146 while (pos < len); /* should always be true */
152 * Read the contents of a binary file into a buffer.
154 * @param h handle to an open file
155 * @param file name of the source file
156 * @param line line number in the source file
157 * @param result the buffer to write the result to
158 * @param len the number of bytes to read
159 * @return GNUNET_OK on success, GNUNET_SYSERR on failure
161 int GNUNET_BIO_read_fn (struct GNUNET_BIO_ReadHandle *h,
162 const char *file, int line,
167 GNUNET_snprintf (what,
171 return GNUNET_BIO_read (h, what, result, len);
176 * Read 0-terminated string from a file.
178 * @param h handle to an open file
179 * @param what describes what is being read (for error message creation)
180 * @param result the buffer to store a pointer to the (allocated) string to
181 * (note that *result could be set to NULL as well)
182 * @param maxLen maximum allowed length for the string
183 * @return GNUNET_OK on success, GNUNET_SYSERR on failure
186 GNUNET_BIO_read_string (struct GNUNET_BIO_ReadHandle *h,
187 const char *what, char **result, size_t maxLen)
192 if (GNUNET_OK != GNUNET_BIO_read_int32 (h, &big))
194 GNUNET_free_non_null (h->emsg);
195 GNUNET_asprintf (&h->emsg,
196 _("Error reading length of string `%s'"),
198 return GNUNET_SYSERR;
207 GNUNET_asprintf (&h->emsg,
208 _("String `%s' longer than allowed (%u > %u)"),
210 return GNUNET_SYSERR;
212 buf = GNUNET_malloc (big);
217 if (GNUNET_OK != GNUNET_BIO_read (h, what, buf, big))
221 return GNUNET_SYSERR;
228 * Read metadata container from a file.
230 * @param h handle to an open file
231 * @param what describes what is being read (for error message creation)
232 * @param result the buffer to store a pointer to the (allocated) metadata
233 * @return GNUNET_OK on success, GNUNET_SYSERR on failure
236 GNUNET_BIO_read_meta_data (struct GNUNET_BIO_ReadHandle *h,
238 struct GNUNET_CONTAINER_MetaData **result)
242 struct GNUNET_CONTAINER_MetaData *meta;
244 if (GNUNET_BIO_read_int32 (h, (int32_t *) &size) != GNUNET_OK)
245 return GNUNET_SYSERR;
251 if (size > MAX_META_DATA)
253 GNUNET_asprintf (&h->emsg,
254 _("Serialized metadata `%s' larger than allowed (%u>%u)"),
255 what, size, MAX_META_DATA);
256 return GNUNET_SYSERR;
258 buf = GNUNET_malloc (size);
259 if (GNUNET_OK != GNUNET_BIO_read (h, what, buf, size))
262 return GNUNET_SYSERR;
264 meta = GNUNET_CONTAINER_meta_data_deserialize (buf, size);
268 GNUNET_asprintf (&h->emsg,
269 _("Metadata `%s' failed to deserialize"), what);
270 return GNUNET_SYSERR;
279 * Read an (u)int32_t.
281 * @param h hande to open file
282 * @param file name of the source file
283 * @param line line number in the source file
284 * @param i address of 32-bit integer to read
285 * @return GNUNET_OK on success, GNUNET_SYSERR on error
288 GNUNET_BIO_read_int32__ (struct GNUNET_BIO_ReadHandle *h,
295 if (GNUNET_OK != GNUNET_BIO_read_fn (h, file, line, &big, sizeof (int32_t)))
296 return GNUNET_SYSERR;
303 * Read an (u)int64_t.
305 * @param h hande to open file
306 * @param file name of the source file
307 * @param line line number in the source file
308 * @param i address of 64-bit integer to read
309 * @return GNUNET_OK on success, GNUNET_SYSERR on error
312 GNUNET_BIO_read_int64__ (struct GNUNET_BIO_ReadHandle *h,
319 if (GNUNET_OK != GNUNET_BIO_read_fn (h, file, line, &big, sizeof (int64_t)))
320 return GNUNET_SYSERR;
321 *i = GNUNET_ntohll (big);
327 * Handle for buffered writing.
329 struct GNUNET_BIO_WriteHandle
331 struct GNUNET_DISK_FileHandle *fd;
339 * Open a file for writing.
341 * @param fn file name to be opened
342 * @return IO handle on success, NULL on error
344 struct GNUNET_BIO_WriteHandle *
345 GNUNET_BIO_write_open (const char *fn)
347 struct GNUNET_DISK_FileHandle *fd;
348 struct GNUNET_BIO_WriteHandle *h;
350 fd = GNUNET_DISK_file_open (fn,
351 GNUNET_DISK_OPEN_WRITE |
352 GNUNET_DISK_OPEN_TRUNCATE |
353 GNUNET_DISK_OPEN_CREATE,
354 GNUNET_DISK_PERM_USER_READ |
355 GNUNET_DISK_PERM_USER_WRITE);
359 GNUNET_malloc (sizeof (struct GNUNET_BIO_WriteHandle) + BIO_BUFFER_SIZE);
360 h->buffer = (char *) &h[1];
361 h->size = BIO_BUFFER_SIZE;
369 * Close an open file for writing.
371 * @param h file handle
372 * @return GNUNET_OK on success, GNUNET_SYSERR otherwise
375 GNUNET_BIO_write_close (struct GNUNET_BIO_WriteHandle *h)
386 wrt = GNUNET_DISK_file_write (h->fd, h->buffer, h->have);
391 GNUNET_DISK_file_close (h->fd);
399 * Write a buffer to a file.
401 * @param h handle to open file
402 * @param buffer the data to write
403 * @param n number of bytes to write
404 * @return GNUNET_OK on success, GNUNET_SYSERR on error
407 GNUNET_BIO_write (struct GNUNET_BIO_WriteHandle *h,
408 const void *buffer, size_t n)
410 const char *src = buffer;
416 return GNUNET_SYSERR;
420 /* first, just use buffer */
421 min = h->size - h->have;
424 memcpy (&h->buffer[h->have], &src[pos], min);
428 return GNUNET_OK; /* done */
429 GNUNET_assert (h->have == h->size);
430 ret = GNUNET_DISK_file_write (h->fd, h->buffer, h->size);
433 GNUNET_DISK_file_close (h->fd);
435 return GNUNET_SYSERR; /* error */
439 while (pos < n); /* should always be true */
446 * Write a string to a file.
448 * @param h handle to open file
449 * @param s string to write (can be NULL)
450 * @return GNUNET_OK on success, GNUNET_SYSERR on error
453 GNUNET_BIO_write_string (struct GNUNET_BIO_WriteHandle *h, const char *s)
457 slen = (uint32_t) ((s == NULL) ? 0 : strlen (s) + 1);
458 if (GNUNET_OK != GNUNET_BIO_write_int32 (h, slen))
459 return GNUNET_SYSERR;
461 return GNUNET_BIO_write (h, s, slen - 1);
467 * Write metadata container to a file.
469 * @param h handle to open file
470 * @param m metadata to write
471 * @return GNUNET_OK on success, GNUNET_SYSERR on error
474 GNUNET_BIO_write_meta_data (struct GNUNET_BIO_WriteHandle *h,
475 const struct GNUNET_CONTAINER_MetaData *m)
481 return GNUNET_BIO_write_int32 (h, 0);
483 size = GNUNET_CONTAINER_meta_data_serialize (m,
486 GNUNET_CONTAINER_META_DATA_SERIALIZE_PART);
490 return GNUNET_SYSERR;
492 if ( (GNUNET_OK != GNUNET_BIO_write_int32 (h, (uint32_t) size)) ||
493 (GNUNET_OK != GNUNET_BIO_write (h, buf, size)) )
496 return GNUNET_SYSERR;
504 * Write an (u)int32_t.
506 * @param h hande to open file
507 * @param i address of 32-bit integer to write
508 * @return GNUNET_OK on success, GNUNET_SYSERR on error
511 GNUNET_BIO_write_int32 (struct GNUNET_BIO_WriteHandle *h, int32_t i)
515 return GNUNET_BIO_write (h, &big, sizeof (int32_t));
520 * Write an (u)int64_t.
522 * @param h hande to open file
523 * @param i address of 64-bit integer to write
524 * @return GNUNET_OK on success, GNUNET_SYSERR on error
527 GNUNET_BIO_write_int64 (struct GNUNET_BIO_WriteHandle *h, int64_t i)
530 big = GNUNET_htonll (i);
531 return GNUNET_BIO_write (h, &big, sizeof (int64_t));