2 This file is part of GNUnet.
3 (C) 2001-2012 Christian Grothoff (and other contributing authors)
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6 it under the terms of the GNU General Public License as published
7 by the Free Software Foundation; either version 3, or (at your
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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.
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18 Boston, MA 02111-1307, USA.
21 * @file fs/fs_download.c
22 * @brief download methods
23 * @author Christian Grothoff
26 #include "gnunet_constants.h"
27 #include "gnunet_fs_service.h"
33 * Determine if the given download (options and meta data) should cause
34 * use to try to do a recursive download.
37 is_recursive_download (struct GNUNET_FS_DownloadContext *dc)
39 return (0 != (dc->options & GNUNET_FS_DOWNLOAD_OPTION_RECURSIVE)) &&
40 ((GNUNET_YES == GNUNET_FS_meta_data_test_for_directory (dc->meta)) ||
41 ((NULL == dc->meta) &&
42 ((NULL == dc->filename) ||
43 ((strlen (dc->filename) >= strlen (GNUNET_FS_DIRECTORY_EXT)) &&
45 strstr (dc->filename + strlen (dc->filename) -
46 strlen (GNUNET_FS_DIRECTORY_EXT),
47 GNUNET_FS_DIRECTORY_EXT))))));
52 * We're storing the IBLOCKS after the DBLOCKS on disk (so that we
53 * only have to truncate the file once we're done).
55 * Given the offset of a block (with respect to the DBLOCKS) and its
56 * depth, return the offset where we would store this block in the
59 * @param fsize overall file size
60 * @param off offset of the block in the file
61 * @param depth depth of the block in the tree, 0 for DBLOCK
62 * @return off for DBLOCKS (depth == treedepth),
63 * otherwise an offset past the end
64 * of the file that does not overlap
65 * with the range for any other block
68 compute_disk_offset (uint64_t fsize, uint64_t off, unsigned int depth)
71 uint64_t lsize; /* what is the size of all IBlocks for depth "i"? */
72 uint64_t loff; /* where do IBlocks for depth "i" start? */
73 unsigned int ioff; /* which IBlock corresponds to "off" at depth "i"? */
77 /* first IBlocks start at the end of file, rounded up
78 * to full DBLOCK_SIZE */
79 loff = ((fsize + DBLOCK_SIZE - 1) / DBLOCK_SIZE) * DBLOCK_SIZE;
81 ((fsize + DBLOCK_SIZE -
82 1) / DBLOCK_SIZE) * sizeof (struct ContentHashKey);
83 GNUNET_assert (0 == (off % DBLOCK_SIZE));
84 ioff = (off / DBLOCK_SIZE);
85 for (i = 1; i < depth; i++)
88 lsize = (lsize + CHK_PER_INODE - 1) / CHK_PER_INODE;
89 GNUNET_assert (lsize > 0);
90 GNUNET_assert (0 == (ioff % CHK_PER_INODE));
91 ioff /= CHK_PER_INODE;
93 return loff + ioff * sizeof (struct ContentHashKey);
98 * Fill in all of the generic fields for a download event and call the
101 * @param pi structure to fill in
102 * @param dc overall download context
105 GNUNET_FS_download_make_status_ (struct GNUNET_FS_ProgressInfo *pi,
106 struct GNUNET_FS_DownloadContext *dc)
108 pi->value.download.dc = dc;
109 pi->value.download.cctx = dc->client_info;
110 pi->value.download.pctx =
111 (NULL == dc->parent) ? NULL : dc->parent->client_info;
112 pi->value.download.sctx =
113 (NULL == dc->search) ? NULL : dc->search->client_info;
114 pi->value.download.uri = dc->uri;
115 pi->value.download.filename = dc->filename;
116 pi->value.download.size = dc->length;
117 /* FIXME: Fix duration calculation to account for pauses */
118 pi->value.download.duration =
119 GNUNET_TIME_absolute_get_duration (dc->start_time);
120 pi->value.download.completed = dc->completed;
121 pi->value.download.anonymity = dc->anonymity;
122 pi->value.download.eta =
123 GNUNET_TIME_calculate_eta (dc->start_time, dc->completed, dc->length);
124 pi->value.download.is_active = (NULL == dc->client) ? GNUNET_NO : GNUNET_YES;
125 if (0 == (dc->options & GNUNET_FS_DOWNLOAD_IS_PROBE))
126 dc->client_info = dc->h->upcb (dc->h->upcb_cls, pi);
128 dc->client_info = GNUNET_FS_search_probe_progress_ (NULL, pi);
133 * We're ready to transmit a search request to the
134 * file-sharing service. Do it. If there is
135 * more than one request pending, try to send
136 * multiple or request another transmission.
139 * @param size number of bytes available in buf
140 * @param buf where the callee should write the message
141 * @return number of bytes written to buf
144 transmit_download_request (void *cls, size_t size, void *buf);
148 * Closure for iterator processing results.
150 struct ProcessResultClosure
156 struct GNUNET_HashCode query;
159 * Data found in P2P network.
164 * Our download context.
166 struct GNUNET_FS_DownloadContext *dc;
169 * When did we last transmit the request?
171 struct GNUNET_TIME_Absolute last_transmission;
174 * Number of bytes in data.
181 enum GNUNET_BLOCK_Type type;
184 * Flag to indicate if this block should be stored on disk.
189 * how much respect did we offer to get this reply?
191 uint32_t respect_offered;
194 * how often did we transmit the query?
196 uint32_t num_transmissions;
202 * Iterator over entries in the pending requests in the 'active' map for the
203 * reply that we just got.
205 * @param cls closure (our 'struct ProcessResultClosure')
206 * @param key query for the given value / request
207 * @param value value in the hash map (a 'struct DownloadRequest')
208 * @return GNUNET_YES (we should continue to iterate); unless serious error
211 process_result_with_request (void *cls, const struct GNUNET_HashCode * key,
216 * We've found a matching block without downloading it.
217 * Encrypt it and pass it to our "receive" function as
218 * if we had received it from the network.
220 * @param dc download in question
221 * @param chk request this relates to
222 * @param dr request details
223 * @param block plaintext data matching request
224 * @param len number of bytes in block
225 * @param do_store should we still store the block on disk?
226 * @return GNUNET_OK on success
229 encrypt_existing_match (struct GNUNET_FS_DownloadContext *dc,
230 const struct ContentHashKey *chk,
231 struct DownloadRequest *dr, const char *block,
232 size_t len, int do_store)
234 struct ProcessResultClosure prc;
236 struct GNUNET_CRYPTO_AesSessionKey sk;
237 struct GNUNET_CRYPTO_AesInitializationVector iv;
238 struct GNUNET_HashCode query;
240 GNUNET_CRYPTO_hash_to_aes_key (&chk->key, &sk, &iv);
241 if (-1 == GNUNET_CRYPTO_aes_encrypt (block, len, &sk, &iv, enc))
244 return GNUNET_SYSERR;
246 GNUNET_CRYPTO_hash (enc, len, &query);
247 if (0 != memcmp (&query, &chk->query, sizeof (struct GNUNET_HashCode)))
250 return GNUNET_SYSERR;
252 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
253 "Matching %u byte block for `%s' at offset %llu already present, no need for download!\n",
255 dc->filename, (unsigned long long) dr->offset);
256 /* already got it! */
262 dr->depth) ? GNUNET_BLOCK_TYPE_FS_DBLOCK : GNUNET_BLOCK_TYPE_FS_IBLOCK;
263 prc.query = chk->query;
264 prc.do_store = do_store;
265 prc.last_transmission = GNUNET_TIME_UNIT_FOREVER_ABS;
266 process_result_with_request (&prc, &chk->key, dr);
272 * We've lost our connection with the FS service.
273 * Re-establish it and re-transmit all of our
276 * @param dc download context that is having trouble
279 try_reconnect (struct GNUNET_FS_DownloadContext *dc);
283 * We found an entry in a directory. Check if the respective child
284 * already exists and if not create the respective child download.
286 * @param cls the parent download
287 * @param filename name of the file in the directory
288 * @param uri URI of the file (CHK or LOC)
289 * @param meta meta data of the file
290 * @param length number of bytes in data
291 * @param data contents of the file (or NULL if they were not inlined)
294 trigger_recursive_download (void *cls, const char *filename,
295 const struct GNUNET_FS_Uri *uri,
296 const struct GNUNET_CONTAINER_MetaData *meta,
297 size_t length, const void *data);
301 * We're done downloading a directory. Open the file and
302 * trigger all of the (remaining) child downloads.
304 * @param dc context of download that just completed
307 full_recursive_download (struct GNUNET_FS_DownloadContext *dc)
312 struct GNUNET_DISK_FileHandle *h;
313 struct GNUNET_DISK_MapHandle *m;
315 size64 = GNUNET_FS_uri_chk_get_file_size (dc->uri);
316 size = (size_t) size64;
317 if (size64 != (uint64_t) size)
319 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
321 ("Recursive downloads of directories larger than 4 GB are not supported on 32-bit systems\n"));
324 if (NULL != dc->filename)
326 h = GNUNET_DISK_file_open (dc->filename, GNUNET_DISK_OPEN_READ,
327 GNUNET_DISK_PERM_NONE);
331 GNUNET_assert (NULL != dc->temp_filename);
332 h = GNUNET_DISK_file_open (dc->temp_filename, GNUNET_DISK_OPEN_READ,
333 GNUNET_DISK_PERM_NONE);
337 data = GNUNET_DISK_file_map (h, &m, GNUNET_DISK_MAP_TYPE_READ, size);
340 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
341 _("Directory too large for system address space\n"));
345 GNUNET_FS_directory_list_contents (size, data, 0,
346 &trigger_recursive_download, dc);
347 GNUNET_DISK_file_unmap (m);
349 GNUNET_DISK_file_close (h);
350 if (NULL == dc->filename)
352 if (0 != UNLINK (dc->temp_filename))
353 GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING, "unlink",
355 GNUNET_free (dc->temp_filename);
356 dc->temp_filename = NULL;
362 * Check if all child-downloads have completed (or trigger them if
363 * necessary) and once we're completely done, signal completion (and
364 * possibly recurse to parent). This function MUST be called when the
365 * download of a file itself is done or when the download of a file is
366 * done and then later a direct child download has completed (and
367 * hence this download may complete itself).
369 * @param dc download to check for completion of children
372 check_completed (struct GNUNET_FS_DownloadContext *dc)
374 struct GNUNET_FS_ProgressInfo pi;
375 struct GNUNET_FS_DownloadContext *pos;
377 /* first, check if we need to download children */
378 if ((NULL == dc->child_head) && (is_recursive_download (dc)))
379 full_recursive_download (dc);
380 /* then, check if children are done already */
381 for (pos = dc->child_head; NULL != pos; pos = pos->next)
383 if ((pos->emsg == NULL) && (pos->completed < pos->length))
384 return; /* not done yet */
385 if ((pos->child_head != NULL) && (pos->has_finished != GNUNET_YES))
386 return; /* not transitively done yet */
388 /* All of our children are done, so mark this download done */
389 dc->has_finished = GNUNET_YES;
390 if (NULL != dc->job_queue)
392 GNUNET_FS_dequeue_ (dc->job_queue);
393 dc->job_queue = NULL;
395 if (GNUNET_SCHEDULER_NO_TASK != dc->task)
397 GNUNET_SCHEDULER_cancel (dc->task);
398 dc->task = GNUNET_SCHEDULER_NO_TASK;
402 GNUNET_break (GNUNET_OK == GNUNET_DISK_file_close (dc->rfh));
405 GNUNET_FS_download_sync_ (dc);
407 /* signal completion */
408 pi.status = GNUNET_FS_STATUS_DOWNLOAD_COMPLETED;
409 GNUNET_FS_download_make_status_ (&pi, dc);
411 /* let parent know */
412 if (NULL != dc->parent)
413 check_completed (dc->parent);
418 * We got a block of plaintext data (from the meta data).
419 * Try it for upward reconstruction of the data. On success,
420 * the top-level block will move to state BRS_DOWNLOAD_UP.
422 * @param dc context for the download
423 * @param dr download request to match against
424 * @param data plaintext data, starting from the beginning of the file
425 * @param data_len number of bytes in data
428 try_match_block (struct GNUNET_FS_DownloadContext *dc,
429 struct DownloadRequest *dr, const char *data, size_t data_len)
431 struct GNUNET_FS_ProgressInfo pi;
433 char enc[DBLOCK_SIZE];
434 struct ContentHashKey chks[CHK_PER_INODE];
435 struct ContentHashKey in_chk;
436 struct GNUNET_CRYPTO_AesSessionKey sk;
437 struct GNUNET_CRYPTO_AesInitializationVector iv;
439 struct DownloadRequest *drc;
440 struct GNUNET_DISK_FileHandle *fh;
447 odata_len = data_len;
448 if (BRS_DOWNLOAD_UP == dr->state)
452 complete = GNUNET_YES;
453 for (i = 0; i < dr->num_children; i++)
455 drc = dr->children[i];
456 try_match_block (dc, drc, data, data_len);
457 if (drc->state != BRS_RECONSTRUCT_META_UP)
458 complete = GNUNET_NO;
462 if (GNUNET_YES != complete)
464 data = (const char *) chks;
465 dlen = dr->num_children * sizeof (struct ContentHashKey);
469 if (dr->offset > data_len)
471 dlen = GNUNET_MIN (data_len - dr->offset, DBLOCK_SIZE);
473 GNUNET_CRYPTO_hash (&data[dr->offset], dlen, &in_chk.key);
474 GNUNET_CRYPTO_hash_to_aes_key (&in_chk.key, &sk, &iv);
475 if (-1 == GNUNET_CRYPTO_aes_encrypt (&data[dr->offset], dlen, &sk, &iv, enc))
480 GNUNET_CRYPTO_hash (enc, dlen, &in_chk.query);
485 dr->state = BRS_RECONSTRUCT_META_UP;
488 if (0 != memcmp (&in_chk, &dr->chk, sizeof (struct ContentHashKey)))
490 /* other peer provided bogus meta data */
494 /* write block to disk */
495 fn = (NULL != dc->filename) ? dc->filename : dc->temp_filename;
496 fh = GNUNET_DISK_file_open (fn,
497 GNUNET_DISK_OPEN_READWRITE |
498 GNUNET_DISK_OPEN_CREATE |
499 GNUNET_DISK_OPEN_TRUNCATE,
500 GNUNET_DISK_PERM_USER_READ |
501 GNUNET_DISK_PERM_USER_WRITE |
502 GNUNET_DISK_PERM_GROUP_READ |
503 GNUNET_DISK_PERM_OTHER_READ);
506 GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR, "open", fn);
507 GNUNET_asprintf (&dc->emsg, _("Failed to open file `%s' for writing"),
509 GNUNET_DISK_file_close (fh);
510 dr->state = BRS_ERROR;
511 pi.status = GNUNET_FS_STATUS_DOWNLOAD_ERROR;
512 pi.value.download.specifics.error.message = dc->emsg;
513 GNUNET_FS_download_make_status_ (&pi, dc);
516 if (data_len != GNUNET_DISK_file_write (fh, odata, odata_len))
518 GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR, "write", fn);
519 GNUNET_asprintf (&dc->emsg, _("Failed to open file `%s' for writing"),
521 GNUNET_DISK_file_close (fh);
522 dr->state = BRS_ERROR;
523 pi.status = GNUNET_FS_STATUS_DOWNLOAD_ERROR;
524 pi.value.download.specifics.error.message = dc->emsg;
525 GNUNET_FS_download_make_status_ (&pi, dc);
528 GNUNET_DISK_file_close (fh);
530 dr->state = BRS_DOWNLOAD_UP;
531 dc->completed = dc->length;
532 GNUNET_FS_download_sync_ (dc);
533 pi.status = GNUNET_FS_STATUS_DOWNLOAD_PROGRESS;
534 pi.value.download.specifics.progress.data = data;
535 pi.value.download.specifics.progress.offset = 0;
536 pi.value.download.specifics.progress.data_len = dlen;
537 pi.value.download.specifics.progress.depth = 0;
538 pi.value.download.specifics.progress.respect_offered = 0;
539 pi.value.download.specifics.progress.block_download_duration = GNUNET_TIME_UNIT_ZERO;
540 GNUNET_FS_download_make_status_ (&pi, dc);
541 if ((NULL != dc->filename) &&
543 truncate (dc->filename,
544 GNUNET_ntohll (dc->uri->data.chk.file_length))))
545 GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING, "truncate",
547 check_completed (dc);
550 /* how did we get here? */
558 * Type of a function that libextractor calls for each
559 * meta data item found. If we find full data meta data,
560 * call 'try_match_block' on it.
562 * @param cls our 'struct GNUNET_FS_DownloadContext*'
563 * @param plugin_name name of the plugin that produced this value;
564 * special values can be used (i.e. '<zlib>' for zlib being
565 * used in the main libextractor library and yielding
567 * @param type libextractor-type describing the meta data
568 * @param format basic format information about data
569 * @param data_mime_type mime-type of data (not of the original file);
570 * can be NULL (if mime-type is not known)
571 * @param data actual meta-data found
572 * @param data_len number of bytes in data
573 * @return 0 to continue extracting, 1 to abort
576 match_full_data (void *cls, const char *plugin_name,
577 enum EXTRACTOR_MetaType type, enum EXTRACTOR_MetaFormat format,
578 const char *data_mime_type, const char *data, size_t data_len)
580 struct GNUNET_FS_DownloadContext *dc = cls;
582 if (EXTRACTOR_METATYPE_GNUNET_FULL_DATA != type)
584 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Found %u bytes of FD!\n",
585 (unsigned int) data_len);
586 if (GNUNET_FS_uri_chk_get_file_size (dc->uri) != data_len)
589 return 1; /* bogus meta data */
591 try_match_block (dc, dc->top_request, data, data_len);
597 * Set the state of the given download request to
598 * BRS_DOWNLOAD_UP and propagate it up the tree.
600 * @param dr download request that is done
603 propagate_up (struct DownloadRequest *dr)
609 dr->state = BRS_DOWNLOAD_UP;
613 for (i = 0; i < dr->num_children; i++)
614 if (dr->children[i]->state != BRS_DOWNLOAD_UP)
617 while (i == dr->num_children);
622 * Try top-down reconstruction. Before, the given request node
623 * must have the state BRS_CHK_SET. Afterwards, more nodes may
624 * have that state or advanced to BRS_DOWNLOAD_DOWN or even
625 * BRS_DOWNLOAD_UP. It is also possible to get BRS_ERROR on the
628 * @param dc overall download this block belongs to
629 * @param dr block to reconstruct
632 try_top_down_reconstruction (struct GNUNET_FS_DownloadContext *dc,
633 struct DownloadRequest *dr)
636 char block[DBLOCK_SIZE];
637 struct GNUNET_HashCode key;
641 struct DownloadRequest *drc;
642 uint64_t child_block_size;
643 const struct ContentHashKey *chks;
646 GNUNET_assert (NULL != dc->rfh);
647 GNUNET_assert (BRS_CHK_SET == dr->state);
648 total = GNUNET_FS_uri_chk_get_file_size (dc->uri);
649 GNUNET_assert (dr->depth < dc->treedepth);
650 len = GNUNET_FS_tree_calculate_block_size (total, dr->offset, dr->depth);
651 GNUNET_assert (len <= DBLOCK_SIZE);
652 off = compute_disk_offset (total, dr->offset, dr->depth);
653 if (dc->old_file_size < off + len)
654 return; /* failure */
655 if (off != GNUNET_DISK_file_seek (dc->rfh, off, GNUNET_DISK_SEEK_SET))
657 GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING, "seek", dc->filename);
658 return; /* failure */
660 if (len != GNUNET_DISK_file_read (dc->rfh, block, len))
662 GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING, "read", dc->filename);
663 return; /* failure */
665 GNUNET_CRYPTO_hash (block, len, &key);
666 if (0 != memcmp (&key, &dr->chk.key, sizeof (struct GNUNET_HashCode)))
667 return; /* mismatch */
669 encrypt_existing_match (dc, &dr->chk, dr, block, len, GNUNET_NO))
671 /* hash matches but encrypted block does not, really bad */
672 dr->state = BRS_ERROR;
674 while (NULL != dr->parent)
677 dr->state = BRS_ERROR;
682 dr->state = BRS_DOWNLOAD_DOWN;
684 /* set CHKs for children */
685 up_done = GNUNET_YES;
686 chks = (const struct ContentHashKey *) block;
687 for (i = 0; i < dr->num_children; i++)
689 drc = dr->children[i];
690 GNUNET_assert (drc->offset >= dr->offset);
691 child_block_size = GNUNET_FS_tree_compute_tree_size (drc->depth);
692 GNUNET_assert (0 == (drc->offset - dr->offset) % child_block_size);
693 if (BRS_INIT == drc->state)
695 drc->state = BRS_CHK_SET;
696 drc->chk = chks[drc->chk_idx];
697 try_top_down_reconstruction (dc, drc);
699 if (BRS_DOWNLOAD_UP != drc->state)
700 up_done = GNUNET_NO; /* children not all done */
702 if (GNUNET_YES == up_done)
703 propagate_up (dr); /* children all done (or no children...) */
708 * Schedule the download of the specified block in the tree.
710 * @param dc overall download this block belongs to
711 * @param dr request to schedule
714 schedule_block_download (struct GNUNET_FS_DownloadContext *dc,
715 struct DownloadRequest *dr)
724 case BRS_RECONSTRUCT_DOWN:
727 case BRS_RECONSTRUCT_META_UP:
730 case BRS_RECONSTRUCT_UP:
734 /* normal case, start download */
736 case BRS_DOWNLOAD_DOWN:
737 for (i = 0; i < dr->num_children; i++)
738 schedule_block_download (dc, dr->children[i]);
740 case BRS_DOWNLOAD_UP:
747 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
748 "Scheduling download at offset %llu and depth %u for `%s'\n",
749 (unsigned long long) dr->offset, dr->depth,
750 GNUNET_h2s (&dr->chk.query));
752 GNUNET_CONTAINER_multihashmap_contains_value (dc->active, &dr->chk.query,
754 return; /* already active */
755 GNUNET_CONTAINER_multihashmap_put (dc->active, &dr->chk.query, dr,
756 GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE);
757 if (NULL == dc->client)
758 return; /* download not active */
759 GNUNET_CONTAINER_DLL_insert (dc->pending_head, dc->pending_tail, dr);
760 dr->is_pending = GNUNET_YES;
763 GNUNET_CLIENT_notify_transmit_ready (dc->client,
764 sizeof (struct SearchMessage),
765 GNUNET_CONSTANTS_SERVICE_TIMEOUT,
767 &transmit_download_request, dc);
771 #define GNUNET_FS_URI_CHK_PREFIX GNUNET_FS_URI_PREFIX GNUNET_FS_URI_CHK_INFIX
774 * We found an entry in a directory. Check if the respective child
775 * already exists and if not create the respective child download.
777 * @param cls the parent download
778 * @param filename name of the file in the directory
779 * @param uri URI of the file (CHK or LOC)
780 * @param meta meta data of the file
781 * @param length number of bytes in data
782 * @param data contents of the file (or NULL if they were not inlined)
785 trigger_recursive_download (void *cls, const char *filename,
786 const struct GNUNET_FS_Uri *uri,
787 const struct GNUNET_CONTAINER_MetaData *meta,
788 size_t length, const void *data)
790 struct GNUNET_FS_DownloadContext *dc = cls;
791 struct GNUNET_FS_DownloadContext *cpos;
802 return; /* entry for the directory itself */
803 cpos = dc->child_head;
806 if ((GNUNET_FS_uri_test_equal (uri, cpos->uri)) ||
807 ((NULL != filename) && (0 == strcmp (cpos->filename, filename))))
812 return; /* already exists */
814 if (NULL == filename)
816 fn = GNUNET_FS_meta_data_suggest_filename (meta);
819 us = GNUNET_FS_uri_to_string (uri);
820 fn = GNUNET_strdup (&us[strlen (GNUNET_FS_URI_CHK_PREFIX)]);
823 else if ('.' == fn[0])
826 us = GNUNET_FS_uri_to_string (uri);
827 GNUNET_asprintf (&fn, "%s%s", &us[strlen (GNUNET_FS_URI_CHK_PREFIX)],
832 /* change '\' to '/' (this should have happened
833 * during insertion, but malicious peers may
834 * not have done this) */
835 while (NULL != (pos = strstr (fn, "\\")))
837 /* remove '../' everywhere (again, well-behaved
838 * peers don't do this, but don't trust that
839 * we did not get something nasty) */
840 while (NULL != (pos = strstr (fn, "../")))
848 if (NULL == dc->filename)
854 dn = GNUNET_strdup (dc->filename);
855 GNUNET_break ((strlen (dn) >= strlen (GNUNET_FS_DIRECTORY_EXT)) &&
857 strstr (dn + strlen (dn) - strlen (GNUNET_FS_DIRECTORY_EXT),
858 GNUNET_FS_DIRECTORY_EXT)));
859 sfn = GNUNET_strdup (filename);
860 while ((strlen (sfn) > 0) && ('/' == filename[strlen (sfn) - 1]))
861 sfn[strlen (sfn) - 1] = '\0';
862 if ((strlen (dn) >= strlen (GNUNET_FS_DIRECTORY_EXT)) &&
864 strstr (dn + strlen (dn) - strlen (GNUNET_FS_DIRECTORY_EXT),
865 GNUNET_FS_DIRECTORY_EXT)))
866 dn[strlen (dn) - strlen (GNUNET_FS_DIRECTORY_EXT)] = '\0';
867 if ((GNUNET_YES == GNUNET_FS_meta_data_test_for_directory (meta)) &&
868 ((strlen (filename) < strlen (GNUNET_FS_DIRECTORY_EXT)) ||
870 strstr (filename + strlen (filename) -
871 strlen (GNUNET_FS_DIRECTORY_EXT), GNUNET_FS_DIRECTORY_EXT))))
873 GNUNET_asprintf (&full_name, "%s%s%s%s", dn, DIR_SEPARATOR_STR, sfn,
874 GNUNET_FS_DIRECTORY_EXT);
878 GNUNET_asprintf (&full_name, "%s%s%s", dn, DIR_SEPARATOR_STR, sfn);
883 if ((NULL != full_name) &&
884 (GNUNET_OK != GNUNET_DISK_directory_create_for_file (full_name)))
886 GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
888 ("Failed to create directory for recursive download of `%s'\n"),
890 GNUNET_free (full_name);
891 GNUNET_free_non_null (fn);
896 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
897 "Triggering recursive download of size %llu with %u bytes MD\n",
898 (unsigned long long) GNUNET_FS_uri_chk_get_file_size (uri),
900 GNUNET_CONTAINER_meta_data_get_serialized_size (meta));
901 GNUNET_FS_download_start (dc->h, uri, meta, full_name, temp_name, 0,
902 GNUNET_FS_uri_chk_get_file_size (uri),
903 dc->anonymity, dc->options, NULL, dc);
904 GNUNET_free_non_null (full_name);
905 GNUNET_free_non_null (temp_name);
906 GNUNET_free_non_null (fn);
911 * (recursively) free download request structure
913 * @param dr request to free
916 GNUNET_FS_free_download_request_ (struct DownloadRequest *dr)
922 for (i = 0; i < dr->num_children; i++)
923 GNUNET_FS_free_download_request_ (dr->children[i]);
924 GNUNET_free_non_null (dr->children);
930 * Iterator over entries in the pending requests in the 'active' map for the
931 * reply that we just got.
933 * @param cls closure (our 'struct ProcessResultClosure')
934 * @param key query for the given value / request
935 * @param value value in the hash map (a 'struct DownloadRequest')
936 * @return GNUNET_YES (we should continue to iterate); unless serious error
939 process_result_with_request (void *cls, const struct GNUNET_HashCode * key,
942 struct ProcessResultClosure *prc = cls;
943 struct DownloadRequest *dr = value;
944 struct GNUNET_FS_DownloadContext *dc = prc->dc;
945 struct DownloadRequest *drc;
946 struct GNUNET_DISK_FileHandle *fh = NULL;
947 struct GNUNET_CRYPTO_AesSessionKey skey;
948 struct GNUNET_CRYPTO_AesInitializationVector iv;
950 struct GNUNET_FS_ProgressInfo pi;
955 struct ContentHashKey *chkarr;
957 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
958 "Received %u byte block `%s' matching pending request at depth %u and offset %llu/%llu\n",
959 (unsigned int) prc->size,
960 GNUNET_h2s (key), dr->depth, (unsigned long long) dr->offset,
961 (unsigned long long) GNUNET_ntohll (dc->uri->data.
963 bs = GNUNET_FS_tree_calculate_block_size (GNUNET_ntohll
964 (dc->uri->data.chk.file_length),
965 dr->offset, dr->depth);
968 GNUNET_asprintf (&dc->emsg,
970 ("Internal error or bogus download URI (expected %u bytes at depth %u and offset %llu/%llu, got %u bytes)"),
971 bs, dr->depth, (unsigned long long) dr->offset,
972 (unsigned long long) GNUNET_ntohll (dc->uri->data.
975 GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "%s\n", dc->emsg);
976 while (NULL != dr->parent)
978 dr->state = BRS_ERROR;
981 dr->state = BRS_ERROR;
985 (void) GNUNET_CONTAINER_multihashmap_remove (dc->active, &prc->query, dr);
986 if (GNUNET_YES == dr->is_pending)
988 GNUNET_CONTAINER_DLL_remove (dc->pending_head, dc->pending_tail, dr);
989 dr->is_pending = GNUNET_NO;
992 GNUNET_CRYPTO_hash_to_aes_key (&dr->chk.key, &skey, &iv);
993 if (-1 == GNUNET_CRYPTO_aes_decrypt (prc->data, prc->size, &skey, &iv, pt))
996 dc->emsg = GNUNET_strdup (_("internal error decrypting content"));
1000 compute_disk_offset (GNUNET_ntohll (dc->uri->data.chk.file_length),
1001 dr->offset, dr->depth);
1003 if ((GNUNET_YES == prc->do_store) &&
1004 ((NULL != dc->filename) || (is_recursive_download (dc))) &&
1005 ((dr->depth == dc->treedepth) ||
1006 (0 == (dc->options & GNUNET_FS_DOWNLOAD_NO_TEMPORARIES))))
1008 fh = GNUNET_DISK_file_open (NULL != dc->filename
1009 ? dc->filename : dc->temp_filename,
1010 GNUNET_DISK_OPEN_READWRITE |
1011 GNUNET_DISK_OPEN_CREATE,
1012 GNUNET_DISK_PERM_USER_READ |
1013 GNUNET_DISK_PERM_USER_WRITE |
1014 GNUNET_DISK_PERM_GROUP_READ |
1015 GNUNET_DISK_PERM_OTHER_READ);
1018 GNUNET_asprintf (&dc->emsg,
1019 _("Download failed: could not open file `%s': %s"),
1020 dc->filename, STRERROR (errno));
1023 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1024 "Saving decrypted block to disk at offset %llu\n",
1025 (unsigned long long) off);
1026 if ((off != GNUNET_DISK_file_seek (fh, off, GNUNET_DISK_SEEK_SET)))
1028 GNUNET_asprintf (&dc->emsg,
1029 _("Failed to seek to offset %llu in file `%s': %s"),
1030 (unsigned long long) off, dc->filename,
1034 if (prc->size != GNUNET_DISK_file_write (fh, pt, prc->size))
1036 GNUNET_asprintf (&dc->emsg,
1038 ("Failed to write block of %u bytes at offset %llu in file `%s': %s"),
1039 (unsigned int) prc->size, (unsigned long long) off,
1040 dc->filename, STRERROR (errno));
1043 GNUNET_break (GNUNET_OK == GNUNET_DISK_file_close (fh));
1049 /* DBLOCK, update progress and try recursion if applicable */
1051 if (dr->offset < dc->offset)
1053 /* starting offset begins in the middle of pt,
1054 * do not count first bytes as progress */
1055 GNUNET_assert (app > (dc->offset - dr->offset));
1056 app -= (dc->offset - dr->offset);
1058 if (dr->offset + prc->size > dc->offset + dc->length)
1060 /* end of block is after relevant range,
1061 * do not count last bytes as progress */
1062 GNUNET_assert (app >
1063 (dr->offset + prc->size) - (dc->offset + dc->length));
1064 app -= (dr->offset + prc->size) - (dc->offset + dc->length);
1066 dc->completed += app;
1068 /* do recursive download if option is set and either meta data
1069 * says it is a directory or if no meta data is given AND filename
1070 * ends in '.gnd' (top-level case) */
1071 if (is_recursive_download (dc))
1072 GNUNET_FS_directory_list_contents (prc->size, pt, off,
1073 &trigger_recursive_download, dc);
1075 GNUNET_assert (dc->completed <= dc->length);
1076 dr->state = BRS_DOWNLOAD_DOWN;
1077 pi.status = GNUNET_FS_STATUS_DOWNLOAD_PROGRESS;
1078 pi.value.download.specifics.progress.data = pt;
1079 pi.value.download.specifics.progress.offset = dr->offset;
1080 pi.value.download.specifics.progress.data_len = prc->size;
1081 pi.value.download.specifics.progress.depth = dr->depth;
1082 pi.value.download.specifics.progress.respect_offered = prc->respect_offered;
1083 pi.value.download.specifics.progress.num_transmissions = prc->num_transmissions;
1084 if (prc->last_transmission.abs_value != GNUNET_TIME_UNIT_FOREVER_ABS.abs_value)
1085 pi.value.download.specifics.progress.block_download_duration
1086 = GNUNET_TIME_absolute_get_duration (prc->last_transmission);
1088 pi.value.download.specifics.progress.block_download_duration
1089 = GNUNET_TIME_UNIT_ZERO; /* found locally */
1090 GNUNET_FS_download_make_status_ (&pi, dc);
1094 if (dc->completed == dc->length)
1096 /* download completed, signal */
1097 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1098 "Download completed, truncating file to desired length %llu\n",
1099 (unsigned long long) GNUNET_ntohll (dc->uri->data.
1101 /* truncate file to size (since we store IBlocks at the end) */
1102 if (NULL != dc->filename)
1105 truncate (dc->filename,
1106 GNUNET_ntohll (dc->uri->data.chk.file_length)))
1107 GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING, "truncate",
1110 GNUNET_assert (0 == dr->depth);
1111 check_completed (dc);
1115 /* bottom of the tree, no child downloads possible, just sync */
1116 GNUNET_FS_download_sync_ (dc);
1120 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1121 "Triggering downloads of children (this block was at depth %u and offset %llu)\n",
1122 dr->depth, (unsigned long long) dr->offset);
1123 GNUNET_assert (0 == (prc->size % sizeof (struct ContentHashKey)));
1124 chkarr = (struct ContentHashKey *) pt;
1125 for (i = dr->num_children - 1; i >= 0; i--)
1127 drc = dr->children[i];
1131 if ((drc->chk_idx + 1) * sizeof (struct ContentHashKey) > prc->size)
1133 /* 'chkarr' does not have enough space for this chk_idx;
1135 GNUNET_break (0); GNUNET_assert (0);
1136 dc->emsg = GNUNET_strdup (_("internal error decoding tree"));
1139 drc->chk = chkarr[drc->chk_idx];
1140 drc->state = BRS_CHK_SET;
1141 if (GNUNET_YES == dc->issue_requests)
1142 schedule_block_download (dc, drc);
1144 case BRS_RECONSTRUCT_DOWN:
1147 case BRS_RECONSTRUCT_META_UP:
1150 case BRS_RECONSTRUCT_UP:
1156 case BRS_DOWNLOAD_DOWN:
1159 case BRS_DOWNLOAD_UP:
1170 GNUNET_FS_download_sync_ (dc);
1175 GNUNET_DISK_file_close (fh);
1176 pi.status = GNUNET_FS_STATUS_DOWNLOAD_ERROR;
1177 pi.value.download.specifics.error.message = dc->emsg;
1178 GNUNET_FS_download_make_status_ (&pi, dc);
1179 /* abort all pending requests */
1182 GNUNET_CLIENT_notify_transmit_ready_cancel (dc->th);
1185 GNUNET_CLIENT_disconnect (dc->client);
1186 dc->in_receive = GNUNET_NO;
1188 GNUNET_FS_free_download_request_ (dc->top_request);
1189 dc->top_request = NULL;
1190 GNUNET_CONTAINER_multihashmap_destroy (dc->active);
1192 if (NULL != dc->job_queue)
1194 GNUNET_FS_dequeue_ (dc->job_queue);
1195 dc->job_queue = NULL;
1197 dc->pending_head = NULL;
1198 dc->pending_tail = NULL;
1199 GNUNET_FS_download_sync_ (dc);
1205 * Process a download result.
1207 * @param dc our download context
1208 * @param type type of the result
1209 * @param respect_offered how much respect did we offer to get this reply?
1210 * @param num_transmissions how often did we transmit the query?
1211 * @param last_transmission when was this block requested the last time? (FOREVER if unknown/not applicable)
1212 * @param data the (encrypted) response
1213 * @param size size of data
1216 process_result (struct GNUNET_FS_DownloadContext *dc,
1217 enum GNUNET_BLOCK_Type type,
1218 uint32_t respect_offered,
1219 uint32_t num_transmissions,
1220 struct GNUNET_TIME_Absolute last_transmission,
1221 const void *data, size_t size)
1223 struct ProcessResultClosure prc;
1227 prc.last_transmission = last_transmission;
1230 prc.do_store = GNUNET_YES;
1231 prc.respect_offered = respect_offered;
1232 prc.num_transmissions = num_transmissions;
1233 GNUNET_CRYPTO_hash (data, size, &prc.query);
1234 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1235 "Received result for query `%s' from `%s'-service\n",
1236 GNUNET_h2s (&prc.query), "FS");
1237 GNUNET_CONTAINER_multihashmap_get_multiple (dc->active, &prc.query,
1238 &process_result_with_request,
1244 * Type of a function to call when we receive a message
1247 * @param cls closure
1248 * @param msg message received, NULL on timeout or fatal error
1251 receive_results (void *cls, const struct GNUNET_MessageHeader *msg)
1253 struct GNUNET_FS_DownloadContext *dc = cls;
1254 const struct ClientPutMessage *cm;
1257 if ((NULL == msg) || (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_FS_PUT) ||
1258 (sizeof (struct ClientPutMessage) > ntohs (msg->size)))
1260 GNUNET_break (NULL == msg);
1264 msize = ntohs (msg->size);
1265 cm = (const struct ClientPutMessage *) msg;
1266 process_result (dc, ntohl (cm->type),
1267 ntohl (cm->respect_offered),
1268 ntohl (cm->num_transmissions),
1269 GNUNET_TIME_absolute_ntoh (cm->last_transmission), &cm[1],
1270 msize - sizeof (struct ClientPutMessage));
1271 if (NULL == dc->client)
1272 return; /* fatal error */
1273 /* continue receiving */
1274 GNUNET_CLIENT_receive (dc->client, &receive_results, dc,
1275 GNUNET_TIME_UNIT_FOREVER_REL);
1280 * We're ready to transmit a search request to the
1281 * file-sharing service. Do it. If there is
1282 * more than one request pending, try to send
1283 * multiple or request another transmission.
1285 * @param cls closure
1286 * @param size number of bytes available in buf
1287 * @param buf where the callee should write the message
1288 * @return number of bytes written to buf
1291 transmit_download_request (void *cls, size_t size, void *buf)
1293 struct GNUNET_FS_DownloadContext *dc = cls;
1295 struct SearchMessage *sm;
1296 struct DownloadRequest *dr;
1301 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1302 "Transmitting download request failed, trying to reconnect\n");
1306 GNUNET_assert (size >= sizeof (struct SearchMessage));
1309 while ((NULL != (dr = dc->pending_head)) &&
1310 (size >= msize + sizeof (struct SearchMessage)))
1312 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1313 "Transmitting download request for `%s' to `%s'-service\n",
1314 GNUNET_h2s (&dr->chk.query), "FS");
1315 memset (sm, 0, sizeof (struct SearchMessage));
1316 sm->header.size = htons (sizeof (struct SearchMessage));
1317 sm->header.type = htons (GNUNET_MESSAGE_TYPE_FS_START_SEARCH);
1318 if (0 != (dc->options & GNUNET_FS_DOWNLOAD_OPTION_LOOPBACK_ONLY))
1319 sm->options = htonl (GNUNET_FS_SEARCH_OPTION_LOOPBACK_ONLY);
1321 sm->options = htonl (GNUNET_FS_SEARCH_OPTION_NONE);
1323 sm->type = htonl (GNUNET_BLOCK_TYPE_FS_DBLOCK);
1325 sm->type = htonl (GNUNET_BLOCK_TYPE_FS_IBLOCK);
1326 sm->anonymity_level = htonl (dc->anonymity);
1327 sm->target = dc->target.hashPubKey;
1328 sm->query = dr->chk.query;
1329 GNUNET_CONTAINER_DLL_remove (dc->pending_head, dc->pending_tail, dr);
1330 dr->is_pending = GNUNET_NO;
1331 msize += sizeof (struct SearchMessage);
1334 if (NULL != dc->pending_head)
1337 GNUNET_CLIENT_notify_transmit_ready (dc->client,
1338 sizeof (struct SearchMessage),
1339 GNUNET_CONSTANTS_SERVICE_TIMEOUT,
1341 &transmit_download_request, dc);
1342 GNUNET_assert (NULL != dc->th);
1344 if (GNUNET_NO == dc->in_receive)
1346 dc->in_receive = GNUNET_YES;
1347 GNUNET_CLIENT_receive (dc->client, &receive_results, dc,
1348 GNUNET_TIME_UNIT_FOREVER_REL);
1355 * Reconnect to the FS service and transmit our queries NOW.
1357 * @param cls our download context
1361 do_reconnect (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1363 struct GNUNET_FS_DownloadContext *dc = cls;
1364 struct GNUNET_CLIENT_Connection *client;
1366 dc->task = GNUNET_SCHEDULER_NO_TASK;
1367 client = GNUNET_CLIENT_connect ("fs", dc->h->cfg);
1370 GNUNET_log (GNUNET_ERROR_TYPE_WARNING,
1371 "Connecting to `%s'-service failed, will try again.\n", "FS");
1375 dc->client = client;
1376 if (NULL != dc->pending_head)
1379 GNUNET_CLIENT_notify_transmit_ready (client,
1380 sizeof (struct SearchMessage),
1381 GNUNET_CONSTANTS_SERVICE_TIMEOUT,
1383 &transmit_download_request, dc);
1384 GNUNET_assert (NULL != dc->th);
1390 * Add entries to the pending list.
1392 * @param cls our download context
1394 * @param entry entry of type "struct DownloadRequest"
1398 retry_entry (void *cls, const struct GNUNET_HashCode * key, void *entry)
1400 struct GNUNET_FS_DownloadContext *dc = cls;
1401 struct DownloadRequest *dr = entry;
1405 GNUNET_CONTAINER_DLL_insert (dc->pending_head, dc->pending_tail, dr);
1406 dr->is_pending = GNUNET_YES;
1412 * We've lost our connection with the FS service.
1413 * Re-establish it and re-transmit all of our
1416 * @param dc download context that is having trouble
1419 try_reconnect (struct GNUNET_FS_DownloadContext *dc)
1422 if (NULL != dc->client)
1424 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1425 "Moving all requests back to pending list\n");
1428 GNUNET_CLIENT_notify_transmit_ready_cancel (dc->th);
1431 /* full reset of the pending list */
1432 dc->pending_head = NULL;
1433 dc->pending_tail = NULL;
1434 GNUNET_CONTAINER_multihashmap_iterate (dc->active, &retry_entry, dc);
1435 GNUNET_CLIENT_disconnect (dc->client);
1436 dc->in_receive = GNUNET_NO;
1439 if (0 == dc->reconnect_backoff.rel_value)
1440 dc->reconnect_backoff = GNUNET_TIME_UNIT_MILLISECONDS;
1442 dc->reconnect_backoff = GNUNET_TIME_STD_BACKOFF (dc->reconnect_backoff);
1444 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Will try to reconnect in %s\n",
1445 GNUNET_STRINGS_relative_time_to_string (dc->reconnect_backoff, GNUNET_YES));
1447 GNUNET_SCHEDULER_add_delayed (dc->reconnect_backoff,
1454 * We're allowed to ask the FS service for our blocks. Start the download.
1456 * @param cls the 'struct GNUNET_FS_DownloadContext'
1457 * @param client handle to use for communcation with FS (we must destroy it!)
1460 activate_fs_download (void *cls, struct GNUNET_CLIENT_Connection *client)
1462 struct GNUNET_FS_DownloadContext *dc = cls;
1463 struct GNUNET_FS_ProgressInfo pi;
1465 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Download activated\n");
1466 GNUNET_assert (NULL != client);
1467 GNUNET_assert (NULL == dc->client);
1468 GNUNET_assert (NULL == dc->th);
1469 GNUNET_assert (NULL != dc->active);
1470 dc->client = client;
1471 pi.status = GNUNET_FS_STATUS_DOWNLOAD_ACTIVE;
1472 GNUNET_FS_download_make_status_ (&pi, dc);
1473 dc->pending_head = NULL;
1474 dc->pending_tail = NULL;
1475 GNUNET_CONTAINER_multihashmap_iterate (dc->active, &retry_entry, dc);
1476 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1477 "Asking for transmission to FS service\n");
1478 if (NULL != dc->pending_head)
1481 GNUNET_CLIENT_notify_transmit_ready (dc->client,
1482 sizeof (struct SearchMessage),
1483 GNUNET_CONSTANTS_SERVICE_TIMEOUT,
1485 &transmit_download_request, dc);
1486 GNUNET_assert (NULL != dc->th);
1492 * We must stop to ask the FS service for our blocks. Pause the download.
1494 * @param cls the 'struct GNUNET_FS_DownloadContext'
1497 deactivate_fs_download (void *cls)
1499 struct GNUNET_FS_DownloadContext *dc = cls;
1500 struct GNUNET_FS_ProgressInfo pi;
1502 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Download deactivated\n");
1505 GNUNET_CLIENT_notify_transmit_ready_cancel (dc->th);
1508 if (NULL != dc->client)
1510 GNUNET_CLIENT_disconnect (dc->client);
1511 dc->in_receive = GNUNET_NO;
1514 dc->pending_head = NULL;
1515 dc->pending_tail = NULL;
1516 pi.status = GNUNET_FS_STATUS_DOWNLOAD_INACTIVE;
1517 GNUNET_FS_download_make_status_ (&pi, dc);
1522 * (recursively) Create a download request structure.
1524 * @param parent parent of the current entry
1525 * @param chk_idx index of the chk for this block in the parent block
1526 * @param depth depth of the current entry, 0 are the DBLOCKs,
1527 * top level block is 'dc->treedepth - 1'
1528 * @param dr_offset offset in the original file this block maps to
1529 * (as in, offset of the first byte of the first DBLOCK
1530 * in the subtree rooted in the returned download request tree)
1531 * @param file_start_offset desired starting offset for the download
1532 * in the original file; requesting tree should not contain
1533 * DBLOCKs prior to the file_start_offset
1534 * @param desired_length desired number of bytes the user wanted to access
1535 * (from file_start_offset). Resulting tree should not contain
1536 * DBLOCKs after file_start_offset + file_length.
1537 * @return download request tree for the given range of DBLOCKs at
1538 * the specified depth
1540 static struct DownloadRequest *
1541 create_download_request (struct DownloadRequest *parent,
1542 unsigned int chk_idx,
1544 uint64_t dr_offset, uint64_t file_start_offset,
1545 uint64_t desired_length)
1547 struct DownloadRequest *dr;
1549 unsigned int head_skip;
1550 uint64_t child_block_size;
1552 dr = GNUNET_malloc (sizeof (struct DownloadRequest));
1553 dr->parent = parent;
1555 dr->offset = dr_offset;
1556 dr->chk_idx = chk_idx;
1559 child_block_size = GNUNET_FS_tree_compute_tree_size (depth - 1);
1561 /* calculate how many blocks at this level are not interesting
1562 * from the start (rounded down), either because of the requested
1563 * file offset or because this IBlock is further along */
1564 if (dr_offset < file_start_offset)
1566 head_skip = (file_start_offset - dr_offset) / child_block_size;
1573 /* calculate index of last block at this level that is interesting (rounded up) */
1574 dr->num_children = (file_start_offset + desired_length - dr_offset) / child_block_size;
1575 if (dr->num_children * child_block_size <
1576 file_start_offset + desired_length - dr_offset)
1577 dr->num_children++; /* round up */
1578 GNUNET_assert (dr->num_children > head_skip);
1579 dr->num_children -= head_skip;
1580 if (dr->num_children > CHK_PER_INODE)
1581 dr->num_children = CHK_PER_INODE; /* cap at max */
1582 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1583 "Block at offset %llu and depth %u has %u children\n",
1584 (unsigned long long) dr_offset,
1588 /* now we can get the total number of *interesting* children for this block */
1590 /* why else would we have gotten here to begin with? (that'd be a bad logic error) */
1591 GNUNET_assert (dr->num_children > 0);
1594 GNUNET_malloc (dr->num_children * sizeof (struct DownloadRequest *));
1595 for (i = 0; i < dr->num_children; i++)
1598 create_download_request (dr, i + head_skip, depth - 1,
1599 dr_offset + (i + head_skip) * child_block_size,
1600 file_start_offset, desired_length);
1607 * Continuation after a possible attempt to reconstruct
1608 * the current IBlock from the existing file.
1610 * @param cls the 'struct ReconstructContext'
1611 * @param tc scheduler context
1614 reconstruct_cont (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1616 struct GNUNET_FS_DownloadContext *dc = cls;
1618 /* clean up state from tree encoder */
1619 if (dc->task != GNUNET_SCHEDULER_NO_TASK)
1621 GNUNET_SCHEDULER_cancel (dc->task);
1622 dc->task = GNUNET_SCHEDULER_NO_TASK;
1624 if (NULL != dc->rfh)
1626 GNUNET_break (GNUNET_OK == GNUNET_DISK_file_close (dc->rfh));
1629 /* start "normal" download */
1630 dc->issue_requests = GNUNET_YES;
1631 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1632 "Starting normal download\n");
1633 schedule_block_download (dc, dc->top_request);
1638 * Task requesting the next block from the tree encoder.
1640 * @param cls the 'struct GNUJNET_FS_DownloadContext' we're processing
1641 * @param tc task context
1644 get_next_block (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc)
1646 struct GNUNET_FS_DownloadContext *dc = cls;
1648 dc->task = GNUNET_SCHEDULER_NO_TASK;
1649 GNUNET_FS_tree_encoder_next (dc->te);
1654 * Function called asking for the current (encoded)
1655 * block to be processed. After processing the
1656 * client should either call "GNUNET_FS_tree_encode_next"
1657 * or (on error) "GNUNET_FS_tree_encode_finish".
1659 * This function checks if the content on disk matches
1660 * the expected content based on the URI.
1662 * @param cls closure
1663 * @param chk content hash key for the block
1664 * @param offset offset of the block
1665 * @param depth depth of the block, 0 for DBLOCK
1666 * @param type type of the block (IBLOCK or DBLOCK)
1667 * @param block the (encrypted) block
1668 * @param block_size size of block (in bytes)
1671 reconstruct_cb (void *cls, const struct ContentHashKey *chk, uint64_t offset,
1672 unsigned int depth, enum GNUNET_BLOCK_Type type,
1673 const void *block, uint16_t block_size)
1675 struct GNUNET_FS_DownloadContext *dc = cls;
1676 struct GNUNET_FS_ProgressInfo pi;
1677 struct DownloadRequest *dr;
1681 /* find corresponding request entry */
1682 dr = dc->top_request;
1683 while (dr->depth > depth)
1685 GNUNET_assert (dr->num_children > 0);
1686 blen = GNUNET_FS_tree_compute_tree_size (dr->depth - 1);
1687 chld = (offset - dr->offset) / blen;
1688 if (chld < dr->children[0]->chk_idx)
1690 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1691 "Block %u < %u irrelevant for our range\n",
1693 dr->children[0]->chk_idx);
1694 dc->task = GNUNET_SCHEDULER_add_now (&get_next_block, dc);
1695 return; /* irrelevant block */
1697 if (chld > dr->children[dr->num_children-1]->chk_idx)
1699 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1700 "Block %u > %u irrelevant for our range\n",
1702 dr->children[dr->num_children-1]->chk_idx);
1703 dc->task = GNUNET_SCHEDULER_add_now (&get_next_block, dc);
1704 return; /* irrelevant block */
1706 dr = dr->children[chld - dr->children[0]->chk_idx];
1708 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1709 "Matched TE block with request at offset %llu and depth %u in state %d\n",
1710 (unsigned long long) dr->offset,
1713 /* FIXME: this code needs more testing and might
1714 need to handle more states... */
1719 case BRS_RECONSTRUCT_DOWN:
1721 case BRS_RECONSTRUCT_META_UP:
1723 case BRS_RECONSTRUCT_UP:
1726 if (0 == memcmp (chk, &dr->chk, sizeof (struct ContentHashKey)))
1728 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1729 "Reconstruction succeeded, can use block at offset %llu, depth %u\n",
1730 (unsigned long long) offset,
1732 /* block matches, hence tree below matches;
1733 * this request is done! */
1734 dr->state = BRS_DOWNLOAD_UP;
1735 (void) GNUNET_CONTAINER_multihashmap_remove (dc->active, &dr->chk.query, dr);
1736 if (GNUNET_YES == dr->is_pending)
1738 GNUNET_break (0); /* how did we get here? */
1739 GNUNET_CONTAINER_DLL_remove (dc->pending_head, dc->pending_tail, dr);
1740 dr->is_pending = GNUNET_NO;
1742 /* calculate how many bytes of payload this block
1744 blen = GNUNET_FS_tree_compute_tree_size (dr->depth);
1745 /* how many of those bytes are in the requested range? */
1746 blen = GNUNET_MIN (blen, dc->length + dc->offset - dr->offset);
1747 /* signal progress */
1748 dc->completed += blen;
1749 pi.status = GNUNET_FS_STATUS_DOWNLOAD_PROGRESS;
1750 pi.value.download.specifics.progress.data = NULL;
1751 pi.value.download.specifics.progress.offset = offset;
1752 pi.value.download.specifics.progress.data_len = 0;
1753 pi.value.download.specifics.progress.depth = 0;
1754 pi.value.download.specifics.progress.respect_offered = 0;
1755 pi.value.download.specifics.progress.block_download_duration = GNUNET_TIME_UNIT_ZERO;
1756 GNUNET_FS_download_make_status_ (&pi, dc);
1757 /* FIXME: duplicated code from 'process_result_with_request - refactor */
1758 if (dc->completed == dc->length)
1760 /* download completed, signal */
1761 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1762 "Download completed, truncating file to desired length %llu\n",
1763 (unsigned long long) GNUNET_ntohll (dc->uri->data.
1765 /* truncate file to size (since we store IBlocks at the end) */
1766 if (NULL != dc->filename)
1769 truncate (dc->filename,
1770 GNUNET_ntohll (dc->uri->data.chk.file_length)))
1771 GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING, "truncate",
1777 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1778 "Reconstruction failed, need to download block at offset %llu, depth %u\n",
1779 (unsigned long long) offset,
1782 case BRS_DOWNLOAD_DOWN:
1784 case BRS_DOWNLOAD_UP:
1792 dc->task = GNUNET_SCHEDULER_add_now (&get_next_block, dc);
1793 if ((dr == dc->top_request) && (dr->state == BRS_DOWNLOAD_UP))
1794 check_completed (dc);
1799 * Function called by the tree encoder to obtain a block of plaintext
1800 * data (for the lowest level of the tree).
1802 * @param cls our 'struct ReconstructContext'
1803 * @param offset identifies which block to get
1804 * @param max (maximum) number of bytes to get; returning
1805 * fewer will also cause errors
1806 * @param buf where to copy the plaintext buffer
1807 * @param emsg location to store an error message (on error)
1808 * @return number of bytes copied to buf, 0 on error
1811 fh_reader (void *cls, uint64_t offset, size_t max, void *buf, char **emsg)
1813 struct GNUNET_FS_DownloadContext *dc = cls;
1814 struct GNUNET_DISK_FileHandle *fh = dc->rfh;
1819 if (offset != GNUNET_DISK_file_seek (fh, offset, GNUNET_DISK_SEEK_SET))
1822 *emsg = GNUNET_strdup (strerror (errno));
1825 ret = GNUNET_DISK_file_read (fh, buf, max);
1829 *emsg = GNUNET_strdup (strerror (errno));
1837 * Task that creates the initial (top-level) download
1838 * request for the file.
1840 * @param cls the 'struct GNUNET_FS_DownloadContext'
1841 * @param tc scheduler context
1844 GNUNET_FS_download_start_task_ (void *cls,
1845 const struct GNUNET_SCHEDULER_TaskContext *tc)
1847 struct GNUNET_FS_DownloadContext *dc = cls;
1848 struct GNUNET_FS_ProgressInfo pi;
1849 struct GNUNET_DISK_FileHandle *fh;
1851 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Start task running...\n");
1852 dc->task = GNUNET_SCHEDULER_NO_TASK;
1853 if (0 == dc->length)
1855 /* no bytes required! */
1856 if (NULL != dc->filename)
1858 fh = GNUNET_DISK_file_open (dc->filename,
1859 GNUNET_DISK_OPEN_READWRITE |
1860 GNUNET_DISK_OPEN_CREATE |
1862 GNUNET_FS_uri_chk_get_file_size (dc->uri)) ?
1863 GNUNET_DISK_OPEN_TRUNCATE : 0),
1864 GNUNET_DISK_PERM_USER_READ |
1865 GNUNET_DISK_PERM_USER_WRITE |
1866 GNUNET_DISK_PERM_GROUP_READ |
1867 GNUNET_DISK_PERM_OTHER_READ);
1868 GNUNET_DISK_file_close (fh);
1870 GNUNET_FS_download_sync_ (dc);
1871 pi.status = GNUNET_FS_STATUS_DOWNLOAD_START;
1872 pi.value.download.specifics.start.meta = dc->meta;
1873 GNUNET_FS_download_make_status_ (&pi, dc);
1874 check_completed (dc);
1877 if (NULL != dc->emsg)
1879 if (NULL == dc->top_request)
1882 create_download_request (NULL, 0, dc->treedepth - 1, 0, dc->offset,
1884 dc->top_request->state = BRS_CHK_SET;
1885 dc->top_request->chk =
1887 GNUNET_FS_URI_CHK) ? dc->uri->data.chk.chk : dc->uri->data.loc.fi.chk;
1889 GNUNET_FS_download_sync_ (dc);
1890 if (NULL != dc->search)
1891 GNUNET_FS_search_result_sync_ (dc->search);
1892 pi.status = GNUNET_FS_STATUS_DOWNLOAD_START;
1893 pi.value.download.specifics.start.meta = dc->meta;
1894 GNUNET_FS_download_make_status_ (&pi, dc);
1896 GNUNET_FS_download_start_downloading_ (dc);
1897 /* attempt reconstruction from disk */
1898 if (GNUNET_YES == GNUNET_DISK_file_test (dc->filename))
1900 GNUNET_DISK_file_open (dc->filename, GNUNET_DISK_OPEN_READ,
1901 GNUNET_DISK_PERM_NONE);
1902 if (dc->top_request->state == BRS_CHK_SET)
1904 if (NULL != dc->rfh)
1906 /* first, try top-down */
1907 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1908 "Trying top-down reconstruction for `%s'\n", dc->filename);
1909 try_top_down_reconstruction (dc, dc->top_request);
1910 switch (dc->top_request->state)
1914 case BRS_DOWNLOAD_DOWN:
1915 break; /* normal, some blocks already down */
1916 case BRS_DOWNLOAD_UP:
1917 /* already done entirely, party! */
1918 if (NULL != dc->rfh)
1920 /* avoid hanging on to file handle longer than
1922 GNUNET_DISK_file_close (dc->rfh);
1927 GNUNET_asprintf (&dc->emsg, _("Invalid URI"));
1928 GNUNET_FS_download_sync_ (dc);
1929 pi.status = GNUNET_FS_STATUS_DOWNLOAD_ERROR;
1930 pi.value.download.specifics.error.message = dc->emsg;
1931 GNUNET_FS_download_make_status_ (&pi, dc);
1939 /* attempt reconstruction from meta data */
1940 if ((GNUNET_FS_uri_chk_get_file_size (dc->uri) <= MAX_INLINE_SIZE) &&
1943 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1944 "Trying to find embedded meta data for download of size %llu with %u bytes MD\n",
1945 (unsigned long long) GNUNET_FS_uri_chk_get_file_size (dc->uri),
1947 GNUNET_CONTAINER_meta_data_get_serialized_size (dc->meta));
1948 GNUNET_CONTAINER_meta_data_iterate (dc->meta, &match_full_data, dc);
1949 if (BRS_DOWNLOAD_UP == dc->top_request->state)
1951 if (NULL != dc->rfh)
1953 /* avoid hanging on to file handle longer than
1955 GNUNET_DISK_file_close (dc->rfh);
1958 return; /* finished, status update was already done for us */
1961 if (NULL != dc->rfh)
1963 /* finally, actually run bottom-up */
1964 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
1965 "Trying bottom-up reconstruction of file `%s'\n", dc->filename);
1967 GNUNET_FS_tree_encoder_create (dc->h,
1968 GNUNET_FS_uri_chk_get_file_size (dc->uri),
1970 &reconstruct_cb, NULL,
1972 dc->task = GNUNET_SCHEDULER_add_now (&get_next_block, dc);
1976 /* simple, top-level download */
1977 dc->issue_requests = GNUNET_YES;
1978 schedule_block_download (dc, dc->top_request);
1980 if (BRS_DOWNLOAD_UP == dc->top_request->state)
1981 check_completed (dc);
1986 * Create SUSPEND event for the given download operation
1987 * and then clean up our state (without stop signal).
1989 * @param cls the 'struct GNUNET_FS_DownloadContext' to signal for
1992 GNUNET_FS_download_signal_suspend_ (void *cls)
1994 struct GNUNET_FS_DownloadContext *dc = cls;
1995 struct GNUNET_FS_ProgressInfo pi;
1997 if (NULL != dc->top)
1998 GNUNET_FS_end_top (dc->h, dc->top);
1999 while (NULL != dc->child_head)
2000 GNUNET_FS_download_signal_suspend_ (dc->child_head);
2001 if (NULL != dc->search)
2003 dc->search->download = NULL;
2006 if (NULL != dc->job_queue)
2008 GNUNET_FS_dequeue_ (dc->job_queue);
2009 dc->job_queue = NULL;
2011 if (NULL != dc->parent)
2012 GNUNET_CONTAINER_DLL_remove (dc->parent->child_head, dc->parent->child_tail,
2014 if (GNUNET_SCHEDULER_NO_TASK != dc->task)
2016 GNUNET_SCHEDULER_cancel (dc->task);
2017 dc->task = GNUNET_SCHEDULER_NO_TASK;
2019 pi.status = GNUNET_FS_STATUS_DOWNLOAD_SUSPEND;
2020 GNUNET_FS_download_make_status_ (&pi, dc);
2023 GNUNET_FS_tree_encoder_finish (dc->te, NULL, NULL);
2026 if (NULL != dc->rfh)
2028 GNUNET_DISK_file_close (dc->rfh);
2031 GNUNET_FS_free_download_request_ (dc->top_request);
2032 if (NULL != dc->active)
2034 GNUNET_CONTAINER_multihashmap_destroy (dc->active);
2037 GNUNET_free_non_null (dc->filename);
2038 GNUNET_CONTAINER_meta_data_destroy (dc->meta);
2039 GNUNET_FS_uri_destroy (dc->uri);
2040 GNUNET_free_non_null (dc->temp_filename);
2041 GNUNET_free_non_null (dc->serialization);
2042 GNUNET_assert (NULL == dc->job_queue);
2048 * Helper function to setup the download context.
2050 * @param h handle to the file sharing subsystem
2051 * @param uri the URI of the file (determines what to download); CHK or LOC URI
2052 * @param meta known metadata for the file (can be NULL)
2053 * @param filename where to store the file, maybe NULL (then no file is
2054 * created on disk and data must be grabbed from the callbacks)
2055 * @param tempname where to store temporary file data, not used if filename is non-NULL;
2056 * can be NULL (in which case we will pick a name if needed); the temporary file
2057 * may already exist, in which case we will try to use the data that is there and
2058 * if it is not what is desired, will overwrite it
2059 * @param offset at what offset should we start the download (typically 0)
2060 * @param length how many bytes should be downloaded starting at offset
2061 * @param anonymity anonymity level to use for the download
2062 * @param options various options
2063 * @param cctx initial value for the client context for this download
2064 * @return context that can be used to control this download
2066 struct GNUNET_FS_DownloadContext *
2067 create_download_context (struct GNUNET_FS_Handle *h,
2068 const struct GNUNET_FS_Uri *uri,
2069 const struct GNUNET_CONTAINER_MetaData *meta,
2070 const char *filename, const char *tempname,
2071 uint64_t offset, uint64_t length, uint32_t anonymity,
2072 enum GNUNET_FS_DownloadOptions options, void *cctx)
2074 struct GNUNET_FS_DownloadContext *dc;
2076 GNUNET_assert (GNUNET_FS_uri_test_chk (uri) || GNUNET_FS_uri_test_loc (uri));
2077 if ((offset + length < offset) ||
2078 (offset + length > GNUNET_FS_uri_chk_get_file_size (uri)))
2083 dc = GNUNET_malloc (sizeof (struct GNUNET_FS_DownloadContext));
2084 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2085 "Starting download %p, %u bytes at offset %llu\n",
2087 (unsigned long long) length,
2088 (unsigned long long) offset);
2090 dc->uri = GNUNET_FS_uri_dup (uri);
2091 dc->meta = GNUNET_CONTAINER_meta_data_duplicate (meta);
2092 dc->client_info = cctx;
2093 dc->start_time = GNUNET_TIME_absolute_get ();
2094 if (NULL != filename)
2096 dc->filename = GNUNET_strdup (filename);
2097 if (GNUNET_YES == GNUNET_DISK_file_test (filename))
2098 GNUNET_break (GNUNET_OK == GNUNET_DISK_file_size (filename, &dc->old_file_size, GNUNET_YES, GNUNET_YES));
2100 if (GNUNET_FS_uri_test_loc (dc->uri))
2101 GNUNET_assert (GNUNET_OK ==
2102 GNUNET_FS_uri_loc_get_peer_identity (dc->uri, &dc->target));
2103 dc->offset = offset;
2104 dc->length = length;
2105 dc->anonymity = anonymity;
2106 dc->options = options;
2108 GNUNET_CONTAINER_multihashmap_create (1 + 2 * (length / DBLOCK_SIZE), GNUNET_NO);
2110 GNUNET_FS_compute_depth (GNUNET_FS_uri_chk_get_file_size (dc->uri));
2111 if ((NULL == filename) && (is_recursive_download (dc)))
2113 if (NULL != tempname)
2114 dc->temp_filename = GNUNET_strdup (tempname);
2116 dc->temp_filename = GNUNET_DISK_mktemp ("gnunet-directory-download-tmp");
2118 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2119 "Starting download `%s' of %llu bytes with tree depth %u\n",
2121 (unsigned long long) length,
2123 dc->task = GNUNET_SCHEDULER_add_now (&GNUNET_FS_download_start_task_, dc);
2129 * Download parts of a file. Note that this will store
2130 * the blocks at the respective offset in the given file. Also, the
2131 * download is still using the blocking of the underlying FS
2132 * encoding. As a result, the download may *write* outside of the
2133 * given boundaries (if offset and length do not match the 32k FS
2134 * block boundaries). <p>
2136 * This function should be used to focus a download towards a
2137 * particular portion of the file (optimization), not to strictly
2138 * limit the download to exactly those bytes.
2140 * @param h handle to the file sharing subsystem
2141 * @param uri the URI of the file (determines what to download); CHK or LOC URI
2142 * @param meta known metadata for the file (can be NULL)
2143 * @param filename where to store the file, maybe NULL (then no file is
2144 * created on disk and data must be grabbed from the callbacks)
2145 * @param tempname where to store temporary file data, not used if filename is non-NULL;
2146 * can be NULL (in which case we will pick a name if needed); the temporary file
2147 * may already exist, in which case we will try to use the data that is there and
2148 * if it is not what is desired, will overwrite it
2149 * @param offset at what offset should we start the download (typically 0)
2150 * @param length how many bytes should be downloaded starting at offset
2151 * @param anonymity anonymity level to use for the download
2152 * @param options various options
2153 * @param cctx initial value for the client context for this download
2154 * @param parent parent download to associate this download with (use NULL
2155 * for top-level downloads; useful for manually-triggered recursive downloads)
2156 * @return context that can be used to control this download
2158 struct GNUNET_FS_DownloadContext *
2159 GNUNET_FS_download_start (struct GNUNET_FS_Handle *h,
2160 const struct GNUNET_FS_Uri *uri,
2161 const struct GNUNET_CONTAINER_MetaData *meta,
2162 const char *filename, const char *tempname,
2163 uint64_t offset, uint64_t length, uint32_t anonymity,
2164 enum GNUNET_FS_DownloadOptions options, void *cctx,
2165 struct GNUNET_FS_DownloadContext *parent)
2167 struct GNUNET_FS_DownloadContext *dc;
2169 dc = create_download_context (h, uri, meta, filename, tempname,
2170 offset, length, anonymity, options, cctx);
2173 dc->parent = parent;
2175 GNUNET_CONTAINER_DLL_insert (parent->child_head, parent->child_tail, dc);
2176 else if (0 == (GNUNET_FS_DOWNLOAD_IS_PROBE & options) )
2178 GNUNET_FS_make_top (dc->h, &GNUNET_FS_download_signal_suspend_, dc);
2184 * Download parts of a file based on a search result. The download
2185 * will be associated with the search result (and the association
2186 * will be preserved when serializing/deserializing the state).
2187 * If the search is stopped, the download will not be aborted but
2188 * be 'promoted' to a stand-alone download.
2190 * As with the other download function, this will store
2191 * the blocks at the respective offset in the given file. Also, the
2192 * download is still using the blocking of the underlying FS
2193 * encoding. As a result, the download may *write* outside of the
2194 * given boundaries (if offset and length do not match the 32k FS
2195 * block boundaries). <p>
2197 * The given range can be used to focus a download towards a
2198 * particular portion of the file (optimization), not to strictly
2199 * limit the download to exactly those bytes.
2201 * @param h handle to the file sharing subsystem
2202 * @param sr the search result to use for the download (determines uri and
2203 * meta data and associations)
2204 * @param filename where to store the file, maybe NULL (then no file is
2205 * created on disk and data must be grabbed from the callbacks)
2206 * @param tempname where to store temporary file data, not used if filename is non-NULL;
2207 * can be NULL (in which case we will pick a name if needed); the temporary file
2208 * may already exist, in which case we will try to use the data that is there and
2209 * if it is not what is desired, will overwrite it
2210 * @param offset at what offset should we start the download (typically 0)
2211 * @param length how many bytes should be downloaded starting at offset
2212 * @param anonymity anonymity level to use for the download
2213 * @param options various download options
2214 * @param cctx initial value for the client context for this download
2215 * @return context that can be used to control this download
2217 struct GNUNET_FS_DownloadContext *
2218 GNUNET_FS_download_start_from_search (struct GNUNET_FS_Handle *h,
2219 struct GNUNET_FS_SearchResult *sr,
2220 const char *filename,
2221 const char *tempname, uint64_t offset,
2222 uint64_t length, uint32_t anonymity,
2223 enum GNUNET_FS_DownloadOptions options,
2226 struct GNUNET_FS_DownloadContext *dc;
2228 if ((NULL == sr) || (NULL != sr->download))
2233 dc = create_download_context (h, sr->uri, sr->meta, filename, tempname,
2234 offset, length, anonymity, options, cctx);
2239 if (NULL != sr->probe_ctx)
2241 GNUNET_FS_download_stop (sr->probe_ctx, GNUNET_YES);
2242 sr->probe_ctx = NULL;
2244 if (GNUNET_SCHEDULER_NO_TASK != sr->probe_ping_task)
2246 GNUNET_SCHEDULER_cancel (sr->probe_ping_task);
2247 sr->probe_ping_task = GNUNET_SCHEDULER_NO_TASK;
2254 * Start the downloading process (by entering the queue).
2256 * @param dc our download context
2259 GNUNET_FS_download_start_downloading_ (struct GNUNET_FS_DownloadContext *dc)
2261 if (dc->completed == dc->length)
2263 GNUNET_assert (NULL == dc->job_queue);
2264 GNUNET_assert (NULL != dc->active);
2266 GNUNET_FS_queue_ (dc->h, &activate_fs_download, &deactivate_fs_download,
2267 dc, (dc->length + DBLOCK_SIZE - 1) / DBLOCK_SIZE,
2268 (0 == (dc->options & GNUNET_FS_DOWNLOAD_IS_PROBE))
2269 ? GNUNET_FS_QUEUE_PRIORITY_NORMAL
2270 : GNUNET_FS_QUEUE_PRIORITY_PROBE);
2271 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
2272 "Download %p put into queue as job %p\n",
2279 * Stop a download (aborts if download is incomplete).
2281 * @param dc handle for the download
2282 * @param do_delete delete files of incomplete downloads
2285 GNUNET_FS_download_stop (struct GNUNET_FS_DownloadContext *dc, int do_delete)
2287 struct GNUNET_FS_ProgressInfo pi;
2289 int search_was_null;
2291 if (NULL != dc->top)
2292 GNUNET_FS_end_top (dc->h, dc->top);
2293 if (GNUNET_SCHEDULER_NO_TASK != dc->task)
2295 GNUNET_SCHEDULER_cancel (dc->task);
2296 dc->task = GNUNET_SCHEDULER_NO_TASK;
2298 search_was_null = (NULL == dc->search);
2299 if (NULL != dc->search)
2301 dc->search->download = NULL;
2302 GNUNET_FS_search_result_sync_ (dc->search);
2305 if (NULL != dc->job_queue)
2307 GNUNET_FS_dequeue_ (dc->job_queue);
2308 dc->job_queue = NULL;
2312 GNUNET_FS_tree_encoder_finish (dc->te, NULL, NULL);
2315 have_children = (NULL != dc->child_head) ? GNUNET_YES : GNUNET_NO;
2316 while (NULL != dc->child_head)
2317 GNUNET_FS_download_stop (dc->child_head, do_delete);
2318 if (NULL != dc->parent)
2319 GNUNET_CONTAINER_DLL_remove (dc->parent->child_head, dc->parent->child_tail,
2321 if (NULL != dc->serialization)
2322 GNUNET_FS_remove_sync_file_ (dc->h,
2323 ((NULL != dc->parent) ||
2324 (! search_was_null)) ? GNUNET_FS_SYNC_PATH_CHILD_DOWNLOAD :
2325 GNUNET_FS_SYNC_PATH_MASTER_DOWNLOAD,
2327 if ((GNUNET_YES == have_children) && (NULL == dc->parent))
2328 GNUNET_FS_remove_sync_dir_ (dc->h,
2329 (! search_was_null) ? GNUNET_FS_SYNC_PATH_CHILD_DOWNLOAD :
2330 GNUNET_FS_SYNC_PATH_MASTER_DOWNLOAD,
2332 pi.status = GNUNET_FS_STATUS_DOWNLOAD_STOPPED;
2333 GNUNET_FS_download_make_status_ (&pi, dc);
2334 GNUNET_FS_free_download_request_ (dc->top_request);
2335 dc->top_request = NULL;
2336 if (NULL != dc->active)
2338 GNUNET_CONTAINER_multihashmap_destroy (dc->active);
2341 if (NULL != dc->filename)
2343 if ((dc->completed != dc->length) && (GNUNET_YES == do_delete))
2345 if ( (0 != UNLINK (dc->filename)) &&
2347 GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING, "unlink",
2350 GNUNET_free (dc->filename);
2352 GNUNET_CONTAINER_meta_data_destroy (dc->meta);
2353 GNUNET_FS_uri_destroy (dc->uri);
2354 if (NULL != dc->temp_filename)
2356 if (0 != UNLINK (dc->temp_filename))
2357 GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR, "unlink",
2359 GNUNET_free (dc->temp_filename);
2361 GNUNET_free_non_null (dc->serialization);
2362 GNUNET_assert (NULL == dc->job_queue);
2366 /* end of fs_download.c */