GNUnet  0.11.x
configuration.c
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1 /*
2  This file is part of GNUnet.
3  Copyright (C) 2006, 2007, 2008, 2009, 2013 GNUnet e.V.
4 
5  GNUnet is free software: you can redistribute it and/or modify it
6  under the terms of the GNU Affero General Public License as published
7  by the Free Software Foundation, either version 3 of the License,
8  or (at your option) any later version.
9 
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  Affero General Public License for more details.
14 
15  You should have received a copy of the GNU Affero General Public License
16  along with this program. If not, see <http://www.gnu.org/licenses/>.
17 
18  SPDX-License-Identifier: AGPL3.0-or-later
19  */
20 
27 #include "platform.h"
28 #include "gnunet_crypto_lib.h"
29 #include "gnunet_strings_lib.h"
31 #include "gnunet_disk_lib.h"
32 
33 #define LOG(kind, ...) GNUNET_log_from (kind, "util", __VA_ARGS__)
34 
35 #define LOG_STRERROR_FILE(kind, syscall, filename) \
36  GNUNET_log_from_strerror_file (kind, "util", syscall, filename)
37 
42 {
46  struct ConfigEntry *next;
47 
51  char *key;
52 
56  char *val;
57 };
58 
59 
64 {
69 
74 
78  char *name;
79 };
80 
81 
86 {
91 
97  int dirty;
98 };
99 
100 
106 {
108 
110 };
111 
112 
120 {
121  return GNUNET_new (struct GNUNET_CONFIGURATION_Handle);
122 }
123 
124 
130 void
132 {
133  struct ConfigSection *sec;
134 
135  while (NULL != (sec = cfg->sections))
137  GNUNET_free (cfg);
138 }
139 
140 
152 int
155  void *cb_cls)
156 {
158  int ret;
159 
161  if (GNUNET_OK != GNUNET_CONFIGURATION_load (cfg, filename))
162  {
163  GNUNET_break (0);
165  return GNUNET_SYSERR;
166  }
167  ret = cb (cb_cls, cfg);
169  return ret;
170 }
171 
172 
184 int
186  const char *mem,
187  size_t size,
188  const char *basedir)
189 {
190  char *line;
191  char *line_orig;
192  size_t line_size;
193  char *pos;
194  unsigned int nr;
195  size_t r_bytes;
196  size_t to_read;
197  size_t i;
198  int emptyline;
199  int ret;
200  char *section;
201  char *eq;
202  char *tag;
203  char *value;
204 
205  ret = GNUNET_OK;
206  section = GNUNET_strdup ("");
207  nr = 0;
208  r_bytes = 0;
209  line_orig = NULL;
210  while (r_bytes < size)
211  {
212  GNUNET_free_non_null (line_orig);
213  /* fgets-like behaviour on buffer */
214  to_read = size - r_bytes;
215  pos = memchr (&mem[r_bytes], '\n', to_read);
216  if (NULL == pos)
217  {
218  line_orig = GNUNET_strndup (&mem[r_bytes], line_size = to_read);
219  r_bytes += line_size;
220  }
221  else
222  {
223  line_orig =
224  GNUNET_strndup (&mem[r_bytes], line_size = (pos - &mem[r_bytes]));
225  r_bytes += line_size + 1;
226  }
227  line = line_orig;
228  /* increment line number */
229  nr++;
230  /* tabs and '\r' are whitespace */
231  emptyline = GNUNET_YES;
232  for (i = 0; i < line_size; i++)
233  {
234  if (line[i] == '\t')
235  line[i] = ' ';
236  if (line[i] == '\r')
237  line[i] = ' ';
238  if (' ' != line[i])
239  emptyline = GNUNET_NO;
240  }
241  /* ignore empty lines */
242  if (GNUNET_YES == emptyline)
243  continue;
244 
245  /* remove tailing whitespace */
246  for (i = line_size - 1; (i >= 1) && (isspace ((unsigned char) line[i]));
247  i--)
248  line[i] = '\0';
249 
250  /* remove leading whitespace */
251  for (; line[0] != '\0' && (isspace ((unsigned char) line[0])); line++)
252  ;
253 
254  /* ignore comments */
255  if (('#' == line[0]) || ('%' == line[0]))
256  continue;
257 
258  /* handle special "@INLINE@" directive */
259  if (0 == strncasecmp (line, "@INLINE@ ", strlen ("@INLINE@ ")))
260  {
261  /* @INLINE@ value */
262  value = &line[strlen ("@INLINE@ ")];
263  if (NULL != basedir)
264  {
265  char *fn;
266 
267  GNUNET_asprintf (&fn, "%s/%s", basedir, value);
268  if (GNUNET_OK != GNUNET_CONFIGURATION_parse (cfg, fn))
269  {
270  GNUNET_free (fn);
271  ret = GNUNET_SYSERR; /* failed to parse included config */
272  break;
273  }
274  GNUNET_free (fn);
275  }
276  else
277  {
279  "Ignoring parsing @INLINE@ configurations, not allowed!\n");
280  ret = GNUNET_SYSERR;
281  break;
282  }
283  continue;
284  }
285  if (('[' == line[0]) && (']' == line[line_size - 1]))
286  {
287  /* [value] */
288  line[line_size - 1] = '\0';
289  value = &line[1];
290  GNUNET_free (section);
291  section = GNUNET_strdup (value);
292  continue;
293  }
294  if (NULL != (eq = strchr (line, '=')))
295  {
296  /* tag = value */
297  tag = GNUNET_strndup (line, eq - line);
298  /* remove tailing whitespace */
299  for (i = strlen (tag) - 1; (i >= 1) && (isspace ((unsigned char) tag[i]));
300  i--)
301  tag[i] = '\0';
302 
303  /* Strip whitespace */
304  value = eq + 1;
305  while (isspace ((unsigned char) value[0]))
306  value++;
307  for (i = strlen (value) - 1;
308  (i >= 1) && (isspace ((unsigned char) value[i]));
309  i--)
310  value[i] = '\0';
311 
312  /* remove quotes */
313  i = 0;
314  if (('"' == value[0]) && ('"' == value[strlen (value) - 1]))
315  {
316  value[strlen (value) - 1] = '\0';
317  value++;
318  }
319  GNUNET_CONFIGURATION_set_value_string (cfg, section, tag, &value[i]);
320  GNUNET_free (tag);
321  continue;
322  }
323  /* parse error */
325  _ ("Syntax error while deserializing in line %u\n"),
326  nr);
327  ret = GNUNET_SYSERR;
328  break;
329  }
330  GNUNET_free_non_null (line_orig);
331  GNUNET_free (section);
332  GNUNET_assert ((GNUNET_OK != ret) || (r_bytes == size));
333  return ret;
334 }
335 
336 
345 int
347  const char *filename)
348 {
349  uint64_t fs64;
350  size_t fs;
351  char *fn;
352  char *mem;
353  char *endsep;
354  int dirty;
355  int ret;
356  ssize_t sret;
357 
358  fn = GNUNET_STRINGS_filename_expand (filename);
359  LOG (GNUNET_ERROR_TYPE_DEBUG, "Asked to parse config file `%s'\n", fn);
360  if (NULL == fn)
361  return GNUNET_SYSERR;
362  dirty = cfg->dirty; /* back up value! */
363  if (GNUNET_SYSERR ==
365  {
367  "Error while determining the file size of `%s'\n",
368  fn);
369  GNUNET_free (fn);
370  return GNUNET_SYSERR;
371  }
372  if (fs64 > SIZE_MAX)
373  {
374  GNUNET_break (0); /* File size is more than the heap size */
375  GNUNET_free (fn);
376  return GNUNET_SYSERR;
377  }
378  fs = fs64;
379  mem = GNUNET_malloc (fs);
380  sret = GNUNET_DISK_fn_read (fn, mem, fs);
381  if ((sret < 0) || (fs != (size_t) sret))
382  {
383  LOG (GNUNET_ERROR_TYPE_WARNING, _ ("Error while reading file `%s'\n"), fn);
384  GNUNET_free (fn);
385  GNUNET_free (mem);
386  return GNUNET_SYSERR;
387  }
388  LOG (GNUNET_ERROR_TYPE_DEBUG, "Deserializing contents of file `%s'\n", fn);
389  endsep = strrchr (fn, (int) '/');
390  if (NULL != endsep)
391  *endsep = '\0';
392  ret = GNUNET_CONFIGURATION_deserialize (cfg, mem, fs, fn);
393  GNUNET_free (fn);
394  GNUNET_free (mem);
395  /* restore dirty flag - anything we set in the meantime
396  * came from disk */
397  cfg->dirty = dirty;
398  return ret;
399 }
400 
401 
409 int
411 {
412  return cfg->dirty;
413 }
414 
415 
424 char *
426  size_t *size)
427 {
428  struct ConfigSection *sec;
429  struct ConfigEntry *ent;
430  char *mem;
431  char *cbuf;
432  char *val;
433  char *pos;
434  size_t m_size;
435  size_t c_size;
436 
437  /* Pass1 : calculate the buffer size required */
438  m_size = 0;
439  for (sec = cfg->sections; NULL != sec; sec = sec->next)
440  {
441  /* For each section we need to add 3 charaters: {'[',']','\n'} */
442  m_size += strlen (sec->name) + 3;
443  for (ent = sec->entries; NULL != ent; ent = ent->next)
444  {
445  if (NULL != ent->val)
446  {
447  /* if val has any '\n' then they occupy +1 character as '\n'->'\\','n' */
448  pos = ent->val;
449  while (NULL != (pos = strstr (pos, "\n")))
450  {
451  m_size++;
452  pos++;
453  }
454  /* For each key = value pair we need to add 4 characters (2
455  spaces and 1 equal-to character and 1 new line) */
456  m_size += strlen (ent->key) + strlen (ent->val) + 4;
457  }
458  }
459  /* A new line after section end */
460  m_size++;
461  }
462 
463  /* Pass2: Allocate memory and write the configuration to it */
464  mem = GNUNET_malloc (m_size);
465  sec = cfg->sections;
466  c_size = 0;
467  *size = c_size;
468  while (NULL != sec)
469  {
470  int len;
471 
472  len = GNUNET_asprintf (&cbuf, "[%s]\n", sec->name);
473  GNUNET_assert (0 < len);
474  GNUNET_memcpy (mem + c_size, cbuf, len);
475  c_size += len;
476  GNUNET_free (cbuf);
477  for (ent = sec->entries; NULL != ent; ent = ent->next)
478  {
479  if (NULL != ent->val)
480  {
481  val = GNUNET_malloc (strlen (ent->val) * 2 + 1);
482  strcpy (val, ent->val);
483  while (NULL != (pos = strstr (val, "\n")))
484  {
485  memmove (&pos[2], &pos[1], strlen (&pos[1]));
486  pos[0] = '\\';
487  pos[1] = 'n';
488  }
489  len = GNUNET_asprintf (&cbuf, "%s = %s\n", ent->key, val);
490  GNUNET_free (val);
491  GNUNET_memcpy (mem + c_size, cbuf, len);
492  c_size += len;
493  GNUNET_free (cbuf);
494  }
495  }
496  GNUNET_memcpy (mem + c_size, "\n", 1);
497  c_size++;
498  sec = sec->next;
499  }
500  GNUNET_assert (c_size == m_size);
501  *size = c_size;
502  return mem;
503 }
504 
505 
513 int
515  const char *filename)
516 {
517  char *fn;
518  char *cfg_buf;
519  size_t size;
520  ssize_t sret;
521 
522  fn = GNUNET_STRINGS_filename_expand (filename);
523  if (fn == NULL)
524  return GNUNET_SYSERR;
526  {
527  GNUNET_free (fn);
528  return GNUNET_SYSERR;
529  }
530  cfg_buf = GNUNET_CONFIGURATION_serialize (cfg, &size);
531  sret = GNUNET_DISK_fn_write (fn,
532  cfg_buf,
533  size,
538  if ((sret < 0) || (size != (size_t) sret))
539  {
540  GNUNET_free (fn);
541  GNUNET_free (cfg_buf);
543  "Writing configuration to file `%s' failed\n",
544  filename);
545  cfg->dirty = GNUNET_SYSERR; /* last write failed */
546  return GNUNET_SYSERR;
547  }
548  GNUNET_free (fn);
549  GNUNET_free (cfg_buf);
550  cfg->dirty = GNUNET_NO; /* last write succeeded */
551  return GNUNET_OK;
552 }
553 
554 
562 void
565  void *iter_cls)
566 {
567  struct ConfigSection *spos;
568  struct ConfigEntry *epos;
569 
570  for (spos = cfg->sections; NULL != spos; spos = spos->next)
571  for (epos = spos->entries; NULL != epos; epos = epos->next)
572  if (NULL != epos->val)
573  iter (iter_cls, spos->name, epos->key, epos->val);
574 }
575 
576 
585 void
587  const struct GNUNET_CONFIGURATION_Handle *cfg,
588  const char *section,
590  void *iter_cls)
591 {
592  struct ConfigSection *spos;
593  struct ConfigEntry *epos;
594 
595  spos = cfg->sections;
596  while ((spos != NULL) && (0 != strcasecmp (spos->name, section)))
597  spos = spos->next;
598  if (NULL == spos)
599  return;
600  for (epos = spos->entries; NULL != epos; epos = epos->next)
601  if (NULL != epos->val)
602  iter (iter_cls, spos->name, epos->key, epos->val);
603 }
604 
605 
613 void
615  const struct GNUNET_CONFIGURATION_Handle *cfg,
617  void *iter_cls)
618 {
619  struct ConfigSection *spos;
620  struct ConfigSection *next;
621 
622  next = cfg->sections;
623  while (next != NULL)
624  {
625  spos = next;
626  next = spos->next;
627  iter (iter_cls, spos->name);
628  }
629 }
630 
631 
638 void
640  const char *section)
641 {
642  struct ConfigSection *spos;
643  struct ConfigSection *prev;
644  struct ConfigEntry *ent;
645 
646  prev = NULL;
647  spos = cfg->sections;
648  while (NULL != spos)
649  {
650  if (0 == strcasecmp (section, spos->name))
651  {
652  if (NULL == prev)
653  cfg->sections = spos->next;
654  else
655  prev->next = spos->next;
656  while (NULL != (ent = spos->entries))
657  {
658  spos->entries = ent->next;
659  GNUNET_free (ent->key);
660  GNUNET_free_non_null (ent->val);
661  GNUNET_free (ent);
662  cfg->dirty = GNUNET_YES;
663  }
664  GNUNET_free (spos->name);
665  GNUNET_free (spos);
666  return;
667  }
668  prev = spos;
669  spos = spos->next;
670  }
671 }
672 
673 
683 static void
684 copy_entry (void *cls,
685  const char *section,
686  const char *option,
687  const char *value)
688 {
689  struct GNUNET_CONFIGURATION_Handle *dst = cls;
690 
691  GNUNET_CONFIGURATION_set_value_string (dst, section, option, value);
692 }
693 
694 
703 {
705 
708  return ret;
709 }
710 
711 
719 static struct ConfigSection *
721  const char *section)
722 {
723  struct ConfigSection *pos;
724 
725  pos = cfg->sections;
726  while ((pos != NULL) && (0 != strcasecmp (section, pos->name)))
727  pos = pos->next;
728  return pos;
729 }
730 
731 
740 static struct ConfigEntry *
742  const char *section,
743  const char *key)
744 {
745  struct ConfigSection *sec;
746  struct ConfigEntry *pos;
747 
748  if (NULL == (sec = find_section (cfg, section)))
749  return NULL;
750  pos = sec->entries;
751  while ((pos != NULL) && (0 != strcasecmp (key, pos->key)))
752  pos = pos->next;
753  return pos;
754 }
755 
756 
767 static void
768 compare_entries (void *cls,
769  const char *section,
770  const char *option,
771  const char *value)
772 {
773  struct DiffHandle *dh = cls;
774  struct ConfigEntry *entNew;
775 
776  entNew = find_entry (dh->cfg_default, section, option);
777  if ((NULL != entNew) && (NULL != entNew->val) &&
778  (0 == strcmp (entNew->val, value)))
779  return;
780  GNUNET_CONFIGURATION_set_value_string (dh->cfgDiff, section, option, value);
781 }
782 
783 
793  const struct GNUNET_CONFIGURATION_Handle *cfg_default,
794  const struct GNUNET_CONFIGURATION_Handle *cfg_new)
795 {
796  struct DiffHandle diffHandle;
797 
798  diffHandle.cfgDiff = GNUNET_CONFIGURATION_create ();
799  diffHandle.cfg_default = cfg_default;
800  GNUNET_CONFIGURATION_iterate (cfg_new, &compare_entries, &diffHandle);
801  return diffHandle.cfgDiff;
802 }
803 
804 
813 int
816  const struct GNUNET_CONFIGURATION_Handle *cfg_new,
817  const char *filename)
818 {
819  int ret;
820  struct GNUNET_CONFIGURATION_Handle *diff;
821 
822  diff = GNUNET_CONFIGURATION_get_diff (cfg_default, cfg_new);
823  ret = GNUNET_CONFIGURATION_write (diff, filename);
825  return ret;
826 }
827 
828 
837 void
839  const char *section,
840  const char *option,
841  const char *value)
842 {
843  struct ConfigSection *sec;
844  struct ConfigEntry *e;
845  char *nv;
846 
847  e = find_entry (cfg, section, option);
848  if (NULL != e)
849  {
850  if (NULL == value)
851  {
853  e->val = NULL;
854  }
855  else
856  {
857  nv = GNUNET_strdup (value);
859  e->val = nv;
860  }
861  return;
862  }
863  sec = find_section (cfg, section);
864  if (sec == NULL)
865  {
866  sec = GNUNET_new (struct ConfigSection);
867  sec->name = GNUNET_strdup (section);
868  sec->next = cfg->sections;
869  cfg->sections = sec;
870  }
871  e = GNUNET_new (struct ConfigEntry);
872  e->key = GNUNET_strdup (option);
873  e->val = GNUNET_strdup (value);
874  e->next = sec->entries;
875  sec->entries = e;
876 }
877 
878 
887 void
889  const char *section,
890  const char *option,
891  unsigned long long number)
892 {
893  char s[64];
894 
895  GNUNET_snprintf (s, 64, "%llu", number);
896  GNUNET_CONFIGURATION_set_value_string (cfg, section, option, s);
897 }
898 
899 
909 int
911  const struct GNUNET_CONFIGURATION_Handle *cfg,
912  const char *section,
913  const char *option,
914  unsigned long long *number)
915 {
916  struct ConfigEntry *e;
917  char dummy[2];
918 
919  if (NULL == (e = find_entry (cfg, section, option)))
920  return GNUNET_SYSERR;
921  if (NULL == e->val)
922  return GNUNET_SYSERR;
923  if (1 != sscanf (e->val, "%llu%1s", number, dummy))
924  return GNUNET_SYSERR;
925  return GNUNET_OK;
926 }
927 
928 
938 int
940  const struct GNUNET_CONFIGURATION_Handle *cfg,
941  const char *section,
942  const char *option,
943  float *number)
944 {
945  struct ConfigEntry *e;
946  char dummy[2];
947 
948  if (NULL == (e = find_entry (cfg, section, option)))
949  return GNUNET_SYSERR;
950  if (NULL == e->val)
951  return GNUNET_SYSERR;
952  if (1 != sscanf (e->val, "%f%1s", number, dummy))
953  return GNUNET_SYSERR;
954  return GNUNET_OK;
955 }
956 
957 
967 int
969  const struct GNUNET_CONFIGURATION_Handle *cfg,
970  const char *section,
971  const char *option,
972  struct GNUNET_TIME_Relative *time)
973 {
974  struct ConfigEntry *e;
975  int ret;
976 
977  if (NULL == (e = find_entry (cfg, section, option)))
978  return GNUNET_SYSERR;
979  if (NULL == e->val)
980  return GNUNET_SYSERR;
982  if (GNUNET_OK != ret)
984  section,
985  option,
986  _ ("Not a valid relative time specification"));
987  return ret;
988 }
989 
990 
1000 int
1002  const struct GNUNET_CONFIGURATION_Handle *cfg,
1003  const char *section,
1004  const char *option,
1005  unsigned long long *size)
1006 {
1007  struct ConfigEntry *e;
1008 
1009  if (NULL == (e = find_entry (cfg, section, option)))
1010  return GNUNET_SYSERR;
1011  if (NULL == e->val)
1012  return GNUNET_SYSERR;
1013  return GNUNET_STRINGS_fancy_size_to_bytes (e->val, size);
1014 }
1015 
1016 
1027 int
1029  const struct GNUNET_CONFIGURATION_Handle *cfg,
1030  const char *section,
1031  const char *option,
1032  char **value)
1033 {
1034  struct ConfigEntry *e;
1035 
1036  if ((NULL == (e = find_entry (cfg, section, option))) || (NULL == e->val))
1037  {
1038  *value = NULL;
1039  return GNUNET_SYSERR;
1040  }
1041  *value = GNUNET_strdup (e->val);
1042  return GNUNET_OK;
1043 }
1044 
1045 
1058 int
1060  const struct GNUNET_CONFIGURATION_Handle *cfg,
1061  const char *section,
1062  const char *option,
1063  const char *const *choices,
1064  const char **value)
1065 {
1066  struct ConfigEntry *e;
1067  unsigned int i;
1068 
1069  if (NULL == (e = find_entry (cfg, section, option)))
1070  return GNUNET_SYSERR;
1071  for (i = 0; NULL != choices[i]; i++)
1072  if (0 == strcasecmp (choices[i], e->val))
1073  break;
1074  if (NULL == choices[i])
1075  {
1077  _ ("Configuration value '%s' for '%s'"
1078  " in section '%s' is not in set of legal choices\n"),
1079  e->val,
1080  option,
1081  section);
1082  return GNUNET_SYSERR;
1083  }
1084  *value = choices[i];
1085  return GNUNET_OK;
1086 }
1087 
1088 
1101 int
1103  const char *section,
1104  const char *option,
1105  void *buf,
1106  size_t buf_size)
1107 {
1108  char *enc;
1109  int res;
1110  size_t data_size;
1111 
1112  if (GNUNET_OK !=
1113  (res =
1114  GNUNET_CONFIGURATION_get_value_string (cfg, section, option, &enc)))
1115  return res;
1116  data_size = (strlen (enc) * 5) / 8;
1117  if (data_size != buf_size)
1118  {
1119  GNUNET_free (enc);
1120  return GNUNET_SYSERR;
1121  }
1122  if (GNUNET_OK !=
1123  GNUNET_STRINGS_string_to_data (enc, strlen (enc), buf, buf_size))
1124  {
1125  GNUNET_free (enc);
1126  return GNUNET_SYSERR;
1127  }
1128  GNUNET_free (enc);
1129  return GNUNET_OK;
1130 }
1131 
1132 
1141 int
1143  const char *section,
1144  const char *option)
1145 {
1146  struct ConfigEntry *e;
1147 
1148  if ((NULL == (e = find_entry (cfg, section, option))) || (NULL == e->val))
1149  return GNUNET_NO;
1150  return GNUNET_YES;
1151 }
1152 
1153 
1169 static char *
1171  char *orig,
1172  unsigned int depth)
1173 {
1174  char *prefix;
1175  char *result;
1176  char *start;
1177  const char *post;
1178  const char *env;
1179  char *def;
1180  char *end;
1181  unsigned int lopen;
1182  char erased_char;
1183  char *erased_pos;
1184  size_t len;
1185 
1186  if (NULL == orig)
1187  return NULL;
1188  if (depth > 128)
1189  {
1191  _ (
1192  "Recursive expansion suspected, aborting $-expansion for term `%s'\n"),
1193  orig);
1194  return orig;
1195  }
1196  LOG (GNUNET_ERROR_TYPE_DEBUG, "Asked to $-expand %s\n", orig);
1197  if ('$' != orig[0])
1198  {
1199  LOG (GNUNET_ERROR_TYPE_DEBUG, "Doesn't start with $ - not expanding\n");
1200  return orig;
1201  }
1202  erased_char = 0;
1203  erased_pos = NULL;
1204  if ('{' == orig[1])
1205  {
1206  start = &orig[2];
1207  lopen = 1;
1208  end = &orig[1];
1209  while (lopen > 0)
1210  {
1211  end++;
1212  switch (*end)
1213  {
1214  case '}':
1215  lopen--;
1216  break;
1217 
1218  case '{':
1219  lopen++;
1220  break;
1221 
1222  case '\0':
1224  _ ("Missing closing `%s' in option `%s'\n"),
1225  "}",
1226  orig);
1227  return orig;
1228 
1229  default:
1230  break;
1231  }
1232  }
1233  erased_char = *end;
1234  erased_pos = end;
1235  *end = '\0';
1236  post = end + 1;
1237  def = strchr (orig, ':');
1238  if (NULL != def)
1239  {
1240  *def = '\0';
1241  def++;
1242  if (('-' == *def) || ('=' == *def))
1243  def++;
1244  def = GNUNET_strdup (def);
1245  }
1246  }
1247  else
1248  {
1249  int i;
1250 
1251  start = &orig[1];
1252  def = NULL;
1253  i = 0;
1254  while ((orig[i] != '/') && (orig[i] != '\\') && (orig[i] != '\0') &&
1255  (orig[i] != ' '))
1256  i++;
1257  if (orig[i] == '\0')
1258  {
1259  post = "";
1260  }
1261  else
1262  {
1263  erased_char = orig[i];
1264  erased_pos = &orig[i];
1265  orig[i] = '\0';
1266  post = &orig[i + 1];
1267  }
1268  }
1270  "Split into `%s' and `%s' with default %s\n",
1271  start,
1272  post,
1273  def);
1274  if (GNUNET_OK !=
1275  GNUNET_CONFIGURATION_get_value_string (cfg, "PATHS", start, &prefix))
1276  {
1277  if (NULL == (env = getenv (start)))
1278  {
1279  /* try default */
1280  def = expand_dollar (cfg, def, depth + 1);
1281  env = def;
1282  }
1283  if (NULL == env)
1284  {
1285  start = GNUNET_strdup (start);
1286  if (erased_pos)
1287  *erased_pos = erased_char;
1289  _ (
1290  "Failed to expand `%s' in `%s' as it is neither found in [PATHS] nor defined as an environmental variable\n"),
1291  start,
1292  orig);
1293  GNUNET_free (start);
1294  return orig;
1295  }
1296  prefix = GNUNET_strdup (env);
1297  }
1298  prefix = GNUNET_CONFIGURATION_expand_dollar (cfg, prefix);
1299  if ((erased_pos) && ('}' != erased_char))
1300  {
1301  len = strlen (prefix) + 1;
1302  prefix = GNUNET_realloc (prefix, len + 1);
1303  prefix[len - 1] = erased_char;
1304  prefix[len] = '\0';
1305  }
1306  result = GNUNET_malloc (strlen (prefix) + strlen (post) + 1);
1307  strcpy (result, prefix);
1308  strcat (result, post);
1309  GNUNET_free_non_null (def);
1310  GNUNET_free (prefix);
1311  GNUNET_free (orig);
1312  return result;
1313 }
1314 
1315 
1332 char *
1334  const struct GNUNET_CONFIGURATION_Handle *cfg,
1335  char *orig)
1336 {
1337  char *dup;
1338  size_t i;
1339  size_t len;
1340 
1341  for (i = 0; '\0' != orig[i]; i++)
1342  {
1343  if ('$' != orig[i])
1344  continue;
1345  dup = GNUNET_strdup (orig + i);
1346  dup = expand_dollar (cfg, dup, 0);
1347  len = strlen (dup) + 1;
1348  orig = GNUNET_realloc (orig, i + len);
1349  GNUNET_memcpy (orig + i, dup, len);
1350  GNUNET_free (dup);
1351  }
1352  return orig;
1353 }
1354 
1355 
1366 int
1368  const struct GNUNET_CONFIGURATION_Handle *cfg,
1369  const char *section,
1370  const char *option,
1371  char **value)
1372 {
1373  char *tmp;
1374 
1375  if (GNUNET_OK !=
1376  GNUNET_CONFIGURATION_get_value_string (cfg, section, option, &tmp))
1377  {
1378  LOG (GNUNET_ERROR_TYPE_DEBUG, "Failed to retrieve filename\n");
1379  *value = NULL;
1380  return GNUNET_SYSERR;
1381  }
1382  tmp = GNUNET_CONFIGURATION_expand_dollar (cfg, tmp);
1383  *value = GNUNET_STRINGS_filename_expand (tmp);
1384  GNUNET_free (tmp);
1385  if (*value == NULL)
1386  return GNUNET_SYSERR;
1387  return GNUNET_OK;
1388 }
1389 
1390 
1400 int
1402  const struct GNUNET_CONFIGURATION_Handle *cfg,
1403  const char *section,
1404  const char *option)
1405 {
1406  static const char *yesno[] = { "YES", "NO", NULL };
1407  const char *val;
1408  int ret;
1409 
1410  ret =
1411  GNUNET_CONFIGURATION_get_value_choice (cfg, section, option, yesno, &val);
1412  if (ret == GNUNET_SYSERR)
1413  return ret;
1414  if (val == yesno[0])
1415  return GNUNET_YES;
1416  return GNUNET_NO;
1417 }
1418 
1419 
1430 int
1432  const struct GNUNET_CONFIGURATION_Handle *cfg,
1433  const char *section,
1434  const char *option,
1436  void *cb_cls)
1437 {
1438  char *list;
1439  char *pos;
1440  char *end;
1441  char old;
1442  int ret;
1443 
1444  if (GNUNET_OK !=
1445  GNUNET_CONFIGURATION_get_value_string (cfg, section, option, &list))
1446  return 0;
1447  GNUNET_assert (list != NULL);
1448  ret = 0;
1449  pos = list;
1450  while (1)
1451  {
1452  while (pos[0] == ' ')
1453  pos++;
1454  if (strlen (pos) == 0)
1455  break;
1456  end = pos + 1;
1457  while ((end[0] != ' ') && (end[0] != '\0'))
1458  {
1459  if (end[0] == '\\')
1460  {
1461  switch (end[1])
1462  {
1463  case '\\':
1464  case ' ':
1465  memmove (end, &end[1], strlen (&end[1]) + 1);
1466 
1467  case '\0':
1468  /* illegal, but just keep it */
1469  break;
1470 
1471  default:
1472  /* illegal, but just ignore that there was a '/' */
1473  break;
1474  }
1475  }
1476  end++;
1477  }
1478  old = end[0];
1479  end[0] = '\0';
1480  if (strlen (pos) > 0)
1481  {
1482  ret++;
1483  if ((cb != NULL) && (GNUNET_OK != cb (cb_cls, pos)))
1484  {
1485  ret = GNUNET_SYSERR;
1486  break;
1487  }
1488  }
1489  if (old == '\0')
1490  break;
1491  pos = end + 1;
1492  }
1493  GNUNET_free (list);
1494  return ret;
1495 }
1496 
1497 
1504 static char *
1505 escape_name (const char *value)
1506 {
1507  char *escaped;
1508  const char *rpos;
1509  char *wpos;
1510 
1511  escaped = GNUNET_malloc (strlen (value) * 2 + 1);
1512  memset (escaped, 0, strlen (value) * 2 + 1);
1513  rpos = value;
1514  wpos = escaped;
1515  while (rpos[0] != '\0')
1516  {
1517  switch (rpos[0])
1518  {
1519  case '\\':
1520  case ' ':
1521  wpos[0] = '\\';
1522  wpos[1] = rpos[0];
1523  wpos += 2;
1524  break;
1525 
1526  default:
1527  wpos[0] = rpos[0];
1528  wpos++;
1529  }
1530  rpos++;
1531  }
1532  return escaped;
1533 }
1534 
1535 
1543 static int
1544 test_match (void *cls, const char *fn)
1545 {
1546  const char *of = cls;
1547 
1548  return (0 == strcmp (of, fn)) ? GNUNET_SYSERR : GNUNET_OK;
1549 }
1550 
1551 
1564 int
1567  const char *section,
1568  const char *option,
1569  const char *value)
1570 {
1571  char *escaped;
1572  char *old;
1573  char *nw;
1574 
1575  if (GNUNET_SYSERR ==
1577  section,
1578  option,
1579  &test_match,
1580  (void *) value))
1581  return GNUNET_NO; /* already exists */
1582  if (GNUNET_OK !=
1583  GNUNET_CONFIGURATION_get_value_string (cfg, section, option, &old))
1584  old = GNUNET_strdup ("");
1585  escaped = escape_name (value);
1586  nw = GNUNET_malloc (strlen (old) + strlen (escaped) + 2);
1587  strcpy (nw, old);
1588  if (strlen (old) > 0)
1589  strcat (nw, " ");
1590  strcat (nw, escaped);
1591  GNUNET_CONFIGURATION_set_value_string (cfg, section, option, nw);
1592  GNUNET_free (old);
1593  GNUNET_free (nw);
1594  GNUNET_free (escaped);
1595  return GNUNET_OK;
1596 }
1597 
1598 
1611 int
1614  const char *section,
1615  const char *option,
1616  const char *value)
1617 {
1618  char *list;
1619  char *pos;
1620  char *end;
1621  char *match;
1622  char old;
1623 
1624  if (GNUNET_OK !=
1625  GNUNET_CONFIGURATION_get_value_string (cfg, section, option, &list))
1626  return GNUNET_NO;
1627  match = escape_name (value);
1628  pos = list;
1629  while (1)
1630  {
1631  while (pos[0] == ' ')
1632  pos++;
1633  if (strlen (pos) == 0)
1634  break;
1635  end = pos + 1;
1636  while ((end[0] != ' ') && (end[0] != '\0'))
1637  {
1638  if (end[0] == '\\')
1639  {
1640  switch (end[1])
1641  {
1642  case '\\':
1643  case ' ':
1644  end++;
1645  break;
1646 
1647  case '\0':
1648  /* illegal, but just keep it */
1649  break;
1650 
1651  default:
1652  /* illegal, but just ignore that there was a '/' */
1653  break;
1654  }
1655  }
1656  end++;
1657  }
1658  old = end[0];
1659  end[0] = '\0';
1660  if (0 == strcmp (pos, match))
1661  {
1662  if (old != '\0')
1663  memmove (pos, &end[1], strlen (&end[1]) + 1);
1664  else
1665  {
1666  if (pos != list)
1667  pos[-1] = '\0';
1668  else
1669  pos[0] = '\0';
1670  }
1671  GNUNET_CONFIGURATION_set_value_string (cfg, section, option, list);
1672  GNUNET_free (list);
1673  GNUNET_free (match);
1674  return GNUNET_OK;
1675  }
1676  if (old == '\0')
1677  break;
1678  end[0] = old;
1679  pos = end + 1;
1680  }
1681  GNUNET_free (list);
1682  GNUNET_free (match);
1683  return GNUNET_NO;
1684 }
1685 
1686 
1696 static int
1697 parse_configuration_file (void *cls, const char *filename)
1698 {
1699  struct GNUNET_CONFIGURATION_Handle *cfg = cls;
1700  char *ext;
1701  int ret;
1702 
1703  /* Examine file extension */
1704  ext = strrchr (filename, '.');
1705  if ((NULL == ext) || (0 != strcmp (ext, ".conf")))
1706  {
1707  GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "Skipping file `%s'\n", filename);
1708  return GNUNET_OK;
1709  }
1710 
1711  ret = GNUNET_CONFIGURATION_parse (cfg, filename);
1712  return ret;
1713 }
1714 
1715 
1724 int
1726  const char *defaults_d)
1727 {
1728  if (GNUNET_SYSERR ==
1730  return GNUNET_SYSERR; /* no configuration at all found */
1731  return GNUNET_OK;
1732 }
1733 
1734 
1735 /* end of configuration.c */
void(* GNUNET_CONFIGURATION_Section_Iterator)(void *cls, const char *section)
Function to iterate over section.
int GNUNET_CONFIGURATION_get_value_time(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option, struct GNUNET_TIME_Relative *time)
Get a configuration value that should be a relative time.
int dirty
Modification indication since last save GNUNET_NO if clean, GNUNET_YES if dirty, GNUNET_SYSERR on err...
Definition: configuration.c:97
int GNUNET_CONFIGURATION_get_value_number(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option, unsigned long long *number)
Get a configuration value that should be a number.
static const struct GNUNET_CONFIGURATION_Handle * cfg
Configuration we are using.
Definition: gnunet-abd.c:36
static int end
Set if we are to shutdown all services (including ARM).
Definition: gnunet-arm.c:34
void GNUNET_CONFIGURATION_iterate_section_values(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, GNUNET_CONFIGURATION_Iterator iter, void *iter_cls)
Iterate over values of a section in the configuration.
static char * escape_name(const char *value)
FIXME.
int GNUNET_CONFIGURATION_write(struct GNUNET_CONFIGURATION_Handle *cfg, const char *filename)
Write configuration file.
int GNUNET_snprintf(char *buf, size_t size, const char *format,...)
Like snprintf, just aborts if the buffer is of insufficient size.
void GNUNET_CONFIGURATION_iterate(const struct GNUNET_CONFIGURATION_Handle *cfg, GNUNET_CONFIGURATION_Iterator iter, void *iter_cls)
Iterate over all options in the configuration.
static int start
Set if we are to start default services (including ARM).
Definition: gnunet-arm.c:39
static size_t data_size
Number of bytes in data.
Definition: gnunet-abd.c:187
char * GNUNET_CONFIGURATION_expand_dollar(const struct GNUNET_CONFIGURATION_Handle *cfg, char *orig)
Expand an expression of the form "$FOO/BAR" to "DIRECTORY/BAR" where either in the "PATHS" section or...
#define GNUNET_assert(cond)
Use this for fatal errors that cannot be handled.
struct ConfigEntry * entries
entries in the section
Definition: configuration.c:73
int GNUNET_STRINGS_fancy_time_to_relative(const char *fancy_time, struct GNUNET_TIME_Relative *rtime)
Convert a given fancy human-readable time to our internal representation.
Definition: strings.c:351
int GNUNET_CONFIGURATION_append_value_filename(struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option, const char *value)
Append a filename to a configuration value that represents a list of filenames.
#define GNUNET_memcpy(dst, src, n)
Call memcpy() but check for n being 0 first.
int GNUNET_CONFIGURATION_get_value_float(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option, float *number)
Get a configuration value that should be a floating point number.
void GNUNET_CONFIGURATION_set_value_number(struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option, unsigned long long number)
Set a configuration value that should be a number.
static int ret
Return value of the commandline.
Definition: gnunet-abd.c:81
static struct Experiment * e
int GNUNET_DISK_directory_create_for_file(const char *filename)
Create the directory structure for storing a file.
Definition: disk.c:684
void(* GNUNET_CONFIGURATION_Iterator)(void *cls, const char *section, const char *option, const char *value)
Function to iterate over options.
int GNUNET_STRINGS_fancy_size_to_bytes(const char *fancy_size, unsigned long long *size)
Convert a given fancy human-readable size to bytes.
Definition: strings.c:319
#define GNUNET_NO
Definition: gnunet_common.h:78
configuration entry
Definition: configuration.c:41
#define GNUNET_OK
Named constants for return values.
Definition: gnunet_common.h:75
#define GNUNET_free_non_null(ptr)
Free the memory pointed to by ptr if ptr is not NULL.
#define GNUNET_new(type)
Allocate a struct or union of the given type.
struct GNUNET_CONFIGURATION_Handle * GNUNET_CONFIGURATION_create()
Create a GNUNET_CONFIGURATION_Handle.
int GNUNET_CONFIGURATION_parse(struct GNUNET_CONFIGURATION_Handle *cfg, const char *filename)
Parse a configuration file, add all of the options in the file to the configuration environment...
void GNUNET_log_config_invalid(enum GNUNET_ErrorType kind, const char *section, const char *option, const char *required)
Log error message about invalid configuration option value.
int GNUNET_DISK_directory_scan(const char *dir_name, GNUNET_FileNameCallback callback, void *callback_cls)
Scan a directory for files.
Definition: disk.c:912
static struct ConfigEntry * find_entry(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *key)
Find an entry from a configuration.
#define GNUNET_strdup(a)
Wrapper around GNUNET_xstrdup_.
#define SIZE_MAX
Definition: platform.h:216
ssize_t GNUNET_DISK_fn_write(const char *fn, const void *buffer, size_t n, enum GNUNET_DISK_AccessPermissions mode)
Write a buffer to a file.
Definition: disk.c:880
#define GNUNET_break(cond)
Use this for internal assertion violations that are not fatal (can be handled) but should not occur...
struct GNUNET_CONFIGURATION_Handle * cfgDiff
uint32_t number
int GNUNET_CONFIGURATION_load(struct GNUNET_CONFIGURATION_Handle *cfg, const char *filename)
Load configuration.
#define _(String)
GNU gettext support macro.
Definition: platform.h:181
static char * section
Name of the section.
Definition: gnunet-config.c:33
static int test_match(void *cls, const char *fn)
FIXME.
int(* GNUNET_CONFIGURATION_Callback)(void *cls, const struct GNUNET_CONFIGURATION_Handle *cfg)
Signature of a function to be run with a configuration.
char * name
name of the section
Definition: configuration.c:78
cryptographic primitives for GNUnet
int GNUNET_asprintf(char **buf, const char *format,...)
Like asprintf, just portable.
int GNUNET_CONFIGURATION_get_data(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option, void *buf, size_t buf_size)
Get crockford32-encoded fixed-size binary data from a configuration.
static char * line
Desired phone line (string to be converted to a hash).
static struct ConfigSection * find_section(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section)
Find a section entry from a configuration.
static char * value
Value of the record to add/remove.
struct GNUNET_CONFIGURATION_Handle * GNUNET_CONFIGURATION_get_diff(const struct GNUNET_CONFIGURATION_Handle *cfg_default, const struct GNUNET_CONFIGURATION_Handle *cfg_new)
Compute configuration with only entries that have been changed.
static char * fn
Filename of the unique file.
#define GNUNET_realloc(ptr, size)
Wrapper around realloc.
int GNUNET_CONFIGURATION_write_diffs(const struct GNUNET_CONFIGURATION_Handle *cfg_default, const struct GNUNET_CONFIGURATION_Handle *cfg_new, const char *filename)
Write only configuration entries that have been changed to configuration file.
int GNUNET_CONFIGURATION_is_dirty(const struct GNUNET_CONFIGURATION_Handle *cfg)
Test if there are configuration options that were changed since the last save.
int GNUNET_CONFIGURATION_have_value(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option)
Test if we have a value for a particular option.
void GNUNET_CONFIGURATION_remove_section(struct GNUNET_CONFIGURATION_Handle *cfg, const char *section)
Remove the given section and all options in it.
void GNUNET_CONFIGURATION_destroy(struct GNUNET_CONFIGURATION_Handle *cfg)
Destroy configuration object.
static char * option
Name of the option.
Definition: gnunet-config.c:38
static char buf[2048]
static char * filename
static int result
Global testing status.
void GNUNET_CONFIGURATION_set_value_string(struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option, const char *value)
Set a configuration value that should be a string.
static void compare_entries(void *cls, const char *section, const char *option, const char *value)
A callback function, compares entries from two configurations (default against a new configuration) a...
static void copy_entry(void *cls, const char *section, const char *option, const char *value)
Copy a configuration value to the given target configuration.
struct ConfigSection * sections
Configuration sections.
Definition: configuration.c:90
int(* GNUNET_FileNameCallback)(void *cls, const char *filename)
Function called with a filename.
#define LOG(kind,...)
Definition: configuration.c:33
int GNUNET_CONFIGURATION_get_value_size(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option, unsigned long long *size)
Get a configuration value that should be a size in bytes.
int GNUNET_CONFIGURATION_load_from(struct GNUNET_CONFIGURATION_Handle *cfg, const char *defaults_d)
Load default configuration.
static int res
int GNUNET_CONFIGURATION_get_value_string(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option, char **value)
Get a configuration value that should be a string.
#define GNUNET_SYSERR
Definition: gnunet_common.h:76
static unsigned int size
Size of the "table".
Definition: peer.c:67
struct ConfigEntry * next
This is a linked list.
Definition: configuration.c:46
configuration section
Definition: configuration.c:63
char * GNUNET_STRINGS_filename_expand(const char *fil)
Complete filename (a la shell) from abbrevition.
Definition: strings.c:603
char * getenv()
struct GNUNET_MQ_Envelope * env
Definition: 005.c:1
Used for diffing a configuration object against the default one.
static struct GNUNET_FS_Handle * fs
Handle to FS service.
Definition: gnunet-fs.c:36
int GNUNET_DISK_file_size(const char *filename, uint64_t *size, int include_symbolic_links, int single_file_mode)
Get the size of the file (or directory) of the given file (in bytes).
Definition: disk.c:257
struct GNUNET_CONFIGURATION_Handle * GNUNET_CONFIGURATION_dup(const struct GNUNET_CONFIGURATION_Handle *cfg)
Duplicate an existing configuration object.
static struct in_addr dummy
Target "dummy" address of the packet we pretend to respond to.
char * GNUNET_CONFIGURATION_serialize(const struct GNUNET_CONFIGURATION_Handle *cfg, size_t *size)
Serializes the given configuration.
#define GNUNET_strndup(a, length)
Wrapper around GNUNET_xstrndup_.
int GNUNET_CONFIGURATION_iterate_value_filenames(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option, GNUNET_FileNameCallback cb, void *cb_cls)
Iterate over the set of filenames stored in a configuration value.
configuration data
Definition: configuration.c:85
char * key
key for this entry
Definition: configuration.c:51
static OpusEncoder * enc
OPUS encoder.
void GNUNET_CONFIGURATION_iterate_sections(const struct GNUNET_CONFIGURATION_Handle *cfg, GNUNET_CONFIGURATION_Section_Iterator iter, void *iter_cls)
Iterate over all sections in the configuration.
#define GNUNET_log(kind,...)
int GNUNET_CONFIGURATION_get_value_filename(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option, char **value)
Get a configuration value that should be a string.
static int parse_configuration_file(void *cls, const char *filename)
Wrapper around GNUNET_CONFIGURATION_parse.
const struct GNUNET_CONFIGURATION_Handle * cfg_default
#define GNUNET_YES
Definition: gnunet_common.h:77
int GNUNET_CONFIGURATION_deserialize(struct GNUNET_CONFIGURATION_Handle *cfg, const char *mem, size_t size, const char *basedir)
De-serializes configuration.
int GNUNET_CONFIGURATION_get_value_choice(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option, const char *const *choices, const char **value)
Get a configuration value that should be in a set of predefined strings.
static char * expand_dollar(const struct GNUNET_CONFIGURATION_Handle *cfg, char *orig, unsigned int depth)
Expand an expression of the form "$FOO/BAR" to "DIRECTORY/BAR" where either in the "PATHS" section or...
int GNUNET_CONFIGURATION_get_value_yesno(const struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option)
Get a configuration value that should be in a set of "YES" or "NO".
struct ConfigSection * next
This is a linked list.
Definition: configuration.c:68
int GNUNET_CONFIGURATION_parse_and_run(const char *filename, GNUNET_CONFIGURATION_Callback cb, void *cb_cls)
Parse a configuration file filename and run the function cb with the resulting configuration object...
static int list
Set if we should print a list of currently running services.
Definition: gnunet-arm.c:69
int GNUNET_CONFIGURATION_remove_value_filename(struct GNUNET_CONFIGURATION_Handle *cfg, const char *section, const char *option, const char *value)
Remove a filename from a configuration value that represents a list of filenames. ...
#define GNUNET_malloc(size)
Wrapper around malloc.
int GNUNET_STRINGS_string_to_data(const char *enc, size_t enclen, void *out, size_t out_size)
Convert CrockfordBase32 encoding back to data.
Definition: strings.c:952
ssize_t GNUNET_DISK_fn_read(const char *fn, void *result, size_t len)
Read the contents of a binary file into a buffer.
Definition: disk.c:794
char * val
current, commited value
Definition: configuration.c:56
#define GNUNET_free(ptr)
Wrapper around free.
Time for relative time used by GNUnet, in microseconds.
uint16_t len
length of data (which is always a uint32_t, but presumably this can be used to specify that fewer byt...