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Diffstat (limited to 'src/fs/fs_download.c')
| -rw-r--r-- | src/fs/fs_download.c | 2260 |
1 files changed, 2260 insertions, 0 deletions
diff --git a/src/fs/fs_download.c b/src/fs/fs_download.c new file mode 100644 index 0000000..b23d14b --- /dev/null +++ b/src/fs/fs_download.c @@ -0,0 +1,2260 @@ +/* + This file is part of GNUnet. + (C) 2001-2011 Christian Grothoff (and other contributing authors) + + GNUnet is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published + by the Free Software Foundation; either version 3, or (at your + option) any later version. + + GNUnet is distributed in the hope that it will be useful, but + WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + General Public License for more details. + + You should have received a copy of the GNU General Public License + along with GNUnet; see the file COPYING. If not, write to the + Free Software Foundation, Inc., 59 Temple Place - Suite 330, + Boston, MA 02111-1307, USA. +*/ +/** + * @file fs/fs_download.c + * @brief download methods + * @author Christian Grothoff + * + * TODO: + * - different priority for scheduling probe downloads? + */ +#include "platform.h" +#include "gnunet_constants.h" +#include "gnunet_fs_service.h" +#include "fs_api.h" +#include "fs_tree.h" + + +/** + * Determine if the given download (options and meta data) should cause + * use to try to do a recursive download. + */ +static int +is_recursive_download (struct GNUNET_FS_DownloadContext *dc) +{ + return (0 != (dc->options & GNUNET_FS_DOWNLOAD_OPTION_RECURSIVE)) && + ((GNUNET_YES == GNUNET_FS_meta_data_test_for_directory (dc->meta)) || + ((dc->meta == NULL) && + ((NULL == dc->filename) || + ((strlen (dc->filename) >= strlen (GNUNET_FS_DIRECTORY_EXT)) && + (NULL != + strstr (dc->filename + strlen (dc->filename) - + strlen (GNUNET_FS_DIRECTORY_EXT), + GNUNET_FS_DIRECTORY_EXT)))))); +} + + +/** + * We're storing the IBLOCKS after the DBLOCKS on disk (so that we + * only have to truncate the file once we're done). + * + * Given the offset of a block (with respect to the DBLOCKS) and its + * depth, return the offset where we would store this block in the + * file. + * + * @param fsize overall file size + * @param off offset of the block in the file + * @param depth depth of the block in the tree, 0 for DBLOCK + * @return off for DBLOCKS (depth == treedepth), + * otherwise an offset past the end + * of the file that does not overlap + * with the range for any other block + */ +static uint64_t +compute_disk_offset (uint64_t fsize, uint64_t off, unsigned int depth) +{ + unsigned int i; + uint64_t lsize; /* what is the size of all IBlocks for depth "i"? */ + uint64_t loff; /* where do IBlocks for depth "i" start? */ + unsigned int ioff; /* which IBlock corresponds to "off" at depth "i"? */ + + if (depth == 0) + return off; + /* first IBlocks start at the end of file, rounded up + * to full DBLOCK_SIZE */ + loff = ((fsize + DBLOCK_SIZE - 1) / DBLOCK_SIZE) * DBLOCK_SIZE; + lsize = + ((fsize + DBLOCK_SIZE - + 1) / DBLOCK_SIZE) * sizeof (struct ContentHashKey); + GNUNET_assert (0 == (off % DBLOCK_SIZE)); + ioff = (off / DBLOCK_SIZE); + for (i = 1; i < depth; i++) + { + loff += lsize; + lsize = (lsize + CHK_PER_INODE - 1) / CHK_PER_INODE; + GNUNET_assert (lsize > 0); + GNUNET_assert (0 == (ioff % CHK_PER_INODE)); + ioff /= CHK_PER_INODE; + } + return loff + ioff * sizeof (struct ContentHashKey); +} + + +/** + * Fill in all of the generic fields for a download event and call the + * callback. + * + * @param pi structure to fill in + * @param dc overall download context + */ +void +GNUNET_FS_download_make_status_ (struct GNUNET_FS_ProgressInfo *pi, + struct GNUNET_FS_DownloadContext *dc) +{ + pi->value.download.dc = dc; + pi->value.download.cctx = dc->client_info; + pi->value.download.pctx = + (dc->parent == NULL) ? NULL : dc->parent->client_info; + pi->value.download.sctx = + (dc->search == NULL) ? NULL : dc->search->client_info; + pi->value.download.uri = dc->uri; + pi->value.download.filename = dc->filename; + pi->value.download.size = dc->length; + /* FIXME: Fix duration calculation to account for pauses */ + pi->value.download.duration = + GNUNET_TIME_absolute_get_duration (dc->start_time); + pi->value.download.completed = dc->completed; + pi->value.download.anonymity = dc->anonymity; + pi->value.download.eta = + GNUNET_TIME_calculate_eta (dc->start_time, dc->completed, dc->length); + pi->value.download.is_active = (dc->client == NULL) ? GNUNET_NO : GNUNET_YES; + if (0 == (dc->options & GNUNET_FS_DOWNLOAD_IS_PROBE)) + dc->client_info = dc->h->upcb (dc->h->upcb_cls, pi); + else + dc->client_info = GNUNET_FS_search_probe_progress_ (NULL, pi); +} + + +/** + * We're ready to transmit a search request to the + * file-sharing service. Do it. If there is + * more than one request pending, try to send + * multiple or request another transmission. + * + * @param cls closure + * @param size number of bytes available in buf + * @param buf where the callee should write the message + * @return number of bytes written to buf + */ +static size_t +transmit_download_request (void *cls, size_t size, void *buf); + + +/** + * Closure for iterator processing results. + */ +struct ProcessResultClosure +{ + + /** + * Hash of data. + */ + GNUNET_HashCode query; + + /** + * Data found in P2P network. + */ + const void *data; + + /** + * Our download context. + */ + struct GNUNET_FS_DownloadContext *dc; + + /** + * Number of bytes in data. + */ + size_t size; + + /** + * Type of data. + */ + enum GNUNET_BLOCK_Type type; + + /** + * Flag to indicate if this block should be stored on disk. + */ + int do_store; + + struct GNUNET_TIME_Absolute last_transmission; + +}; + + +/** + * Iterator over entries in the pending requests in the 'active' map for the + * reply that we just got. + * + * @param cls closure (our 'struct ProcessResultClosure') + * @param key query for the given value / request + * @param value value in the hash map (a 'struct DownloadRequest') + * @return GNUNET_YES (we should continue to iterate); unless serious error + */ +static int +process_result_with_request (void *cls, const GNUNET_HashCode * key, + void *value); + + +/** + * We've found a matching block without downloading it. + * Encrypt it and pass it to our "receive" function as + * if we had received it from the network. + * + * @param dc download in question + * @param chk request this relates to + * @param dr request details + * @param block plaintext data matching request + * @param len number of bytes in block + * @param do_store should we still store the block on disk? + * @return GNUNET_OK on success + */ +static int +encrypt_existing_match (struct GNUNET_FS_DownloadContext *dc, + const struct ContentHashKey *chk, + struct DownloadRequest *dr, const char *block, + size_t len, int do_store) +{ + struct ProcessResultClosure prc; + char enc[len]; + struct GNUNET_CRYPTO_AesSessionKey sk; + struct GNUNET_CRYPTO_AesInitializationVector iv; + GNUNET_HashCode query; + + GNUNET_CRYPTO_hash_to_aes_key (&chk->key, &sk, &iv); + if (-1 == GNUNET_CRYPTO_aes_encrypt (block, len, &sk, &iv, enc)) + { + GNUNET_break (0); + return GNUNET_SYSERR; + } + GNUNET_CRYPTO_hash (enc, len, &query); + if (0 != memcmp (&query, &chk->query, sizeof (GNUNET_HashCode))) + { + GNUNET_break_op (0); + return GNUNET_SYSERR; + } + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Matching block for `%s' at offset %llu already present, no need for download!\n", + dc->filename, (unsigned long long) dr->offset); + /* already got it! */ + prc.dc = dc; + prc.data = enc; + prc.size = len; + prc.type = + (0 == + dr->depth) ? GNUNET_BLOCK_TYPE_FS_DBLOCK : GNUNET_BLOCK_TYPE_FS_IBLOCK; + prc.query = chk->query; + prc.do_store = do_store; + prc.last_transmission = GNUNET_TIME_UNIT_FOREVER_ABS; + process_result_with_request (&prc, &chk->key, dr); + return GNUNET_OK; +} + + +/** + * We've lost our connection with the FS service. + * Re-establish it and re-transmit all of our + * pending requests. + * + * @param dc download context that is having trouble + */ +static void +try_reconnect (struct GNUNET_FS_DownloadContext *dc); + + +/** + * We found an entry in a directory. Check if the respective child + * already exists and if not create the respective child download. + * + * @param cls the parent download + * @param filename name of the file in the directory + * @param uri URI of the file (CHK or LOC) + * @param meta meta data of the file + * @param length number of bytes in data + * @param data contents of the file (or NULL if they were not inlined) + */ +static void +trigger_recursive_download (void *cls, const char *filename, + const struct GNUNET_FS_Uri *uri, + const struct GNUNET_CONTAINER_MetaData *meta, + size_t length, const void *data); + + +/** + * We're done downloading a directory. Open the file and + * trigger all of the (remaining) child downloads. + * + * @param dc context of download that just completed + */ +static void +full_recursive_download (struct GNUNET_FS_DownloadContext *dc) +{ + size_t size; + uint64_t size64; + void *data; + struct GNUNET_DISK_FileHandle *h; + struct GNUNET_DISK_MapHandle *m; + + size64 = GNUNET_FS_uri_chk_get_file_size (dc->uri); + size = (size_t) size64; + if (size64 != (uint64_t) size) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + _ + ("Recursive downloads of directories larger than 4 GB are not supported on 32-bit systems\n")); + return; + } + if (dc->filename != NULL) + { + h = GNUNET_DISK_file_open (dc->filename, GNUNET_DISK_OPEN_READ, + GNUNET_DISK_PERM_NONE); + } + else + { + GNUNET_assert (dc->temp_filename != NULL); + h = GNUNET_DISK_file_open (dc->temp_filename, GNUNET_DISK_OPEN_READ, + GNUNET_DISK_PERM_NONE); + } + if (h == NULL) + return; /* oops */ + data = GNUNET_DISK_file_map (h, &m, GNUNET_DISK_MAP_TYPE_READ, size); + if (data == NULL) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + _("Directory too large for system address space\n")); + } + else + { + GNUNET_FS_directory_list_contents (size, data, 0, + &trigger_recursive_download, dc); + GNUNET_DISK_file_unmap (m); + } + GNUNET_DISK_file_close (h); + if (dc->filename == NULL) + { + if (0 != UNLINK (dc->temp_filename)) + GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING, "unlink", + dc->temp_filename); + GNUNET_free (dc->temp_filename); + dc->temp_filename = NULL; + } +} + + +/** + * Check if all child-downloads have completed (or trigger them if + * necessary) and once we're completely done, signal completion (and + * possibly recurse to parent). This function MUST be called when the + * download of a file itself is done or when the download of a file is + * done and then later a direct child download has completed (and + * hence this download may complete itself). + * + * @param dc download to check for completion of children + */ +static void +check_completed (struct GNUNET_FS_DownloadContext *dc) +{ + struct GNUNET_FS_ProgressInfo pi; + struct GNUNET_FS_DownloadContext *pos; + + /* first, check if we need to download children */ + if ((dc->child_head == NULL) && (is_recursive_download (dc))) + full_recursive_download (dc); + /* then, check if children are done already */ + pos = dc->child_head; + while (pos != NULL) + { + if ((pos->emsg == NULL) && (pos->completed < pos->length)) + return; /* not done yet */ + if ((pos->child_head != NULL) && (pos->has_finished != GNUNET_YES)) + return; /* not transitively done yet */ + pos = pos->next; + } + /* All of our children are done, so mark this download done */ + dc->has_finished = GNUNET_YES; + if (dc->job_queue != NULL) + { + GNUNET_FS_dequeue_ (dc->job_queue); + dc->job_queue = NULL; + } + GNUNET_FS_download_sync_ (dc); + + /* signal completion */ + pi.status = GNUNET_FS_STATUS_DOWNLOAD_COMPLETED; + GNUNET_FS_download_make_status_ (&pi, dc); + + /* let parent know */ + if (dc->parent != NULL) + check_completed (dc->parent); +} + + +/** + * We got a block of plaintext data (from the meta data). + * Try it for upward reconstruction of the data. On success, + * the top-level block will move to state BRS_DOWNLOAD_UP. + * + * @param dc context for the download + * @param dr download request to match against + * @param data plaintext data, starting from the beginning of the file + * @param data_len number of bytes in data + */ +static void +try_match_block (struct GNUNET_FS_DownloadContext *dc, + struct DownloadRequest *dr, const char *data, size_t data_len) +{ + struct GNUNET_FS_ProgressInfo pi; + unsigned int i; + char enc[DBLOCK_SIZE]; + struct ContentHashKey chks[CHK_PER_INODE]; + struct ContentHashKey in_chk; + struct GNUNET_CRYPTO_AesSessionKey sk; + struct GNUNET_CRYPTO_AesInitializationVector iv; + size_t dlen; + struct DownloadRequest *drc; + struct GNUNET_DISK_FileHandle *fh; + int complete; + const char *fn; + const char *odata; + size_t odata_len; + + odata = data; + odata_len = data_len; + if (BRS_DOWNLOAD_UP == dr->state) + return; + if (dr->depth > 0) + { + complete = GNUNET_YES; + for (i = 0; i < dr->num_children; i++) + { + drc = dr->children[i]; + try_match_block (dc, drc, data, data_len); + if (drc->state != BRS_RECONSTRUCT_META_UP) + complete = GNUNET_NO; + else + chks[i] = drc->chk; + } + if (GNUNET_YES != complete) + return; + data = (const char *) chks; + dlen = dr->num_children * sizeof (struct ContentHashKey); + } + else + { + if (dr->offset > data_len) + return; /* oops */ + dlen = GNUNET_MIN (data_len - dr->offset, DBLOCK_SIZE); + } + GNUNET_CRYPTO_hash (&data[dr->offset], dlen, &in_chk.key); + GNUNET_CRYPTO_hash_to_aes_key (&in_chk.key, &sk, &iv); + if (-1 == GNUNET_CRYPTO_aes_encrypt (&data[dr->offset], dlen, &sk, &iv, enc)) + { + GNUNET_break (0); + return; + } + GNUNET_CRYPTO_hash (enc, dlen, &in_chk.query); + switch (dr->state) + { + case BRS_INIT: + dr->chk = in_chk; + dr->state = BRS_RECONSTRUCT_META_UP; + break; + case BRS_CHK_SET: + if (0 != memcmp (&in_chk, &dr->chk, sizeof (struct ContentHashKey))) + { + /* other peer provided bogus meta data */ + GNUNET_break_op (0); + break; + } + /* write block to disk */ + fn = dc->filename != NULL ? dc->filename : dc->temp_filename; + fh = GNUNET_DISK_file_open (fn, + GNUNET_DISK_OPEN_READWRITE | + GNUNET_DISK_OPEN_CREATE | + GNUNET_DISK_OPEN_TRUNCATE, + GNUNET_DISK_PERM_USER_READ | + GNUNET_DISK_PERM_USER_WRITE | + GNUNET_DISK_PERM_GROUP_READ | + GNUNET_DISK_PERM_OTHER_READ); + if (fh == NULL) + { + GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR, "open", fn); + GNUNET_asprintf (&dc->emsg, _("Failed to open file `%s' for writing"), + fn); + GNUNET_DISK_file_close (fh); + dr->state = BRS_ERROR; + pi.status = GNUNET_FS_STATUS_DOWNLOAD_ERROR; + pi.value.download.specifics.error.message = dc->emsg; + GNUNET_FS_download_make_status_ (&pi, dc); + return; + } + if (data_len != GNUNET_DISK_file_write (fh, odata, odata_len)) + { + GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR, "write", fn); + GNUNET_asprintf (&dc->emsg, _("Failed to open file `%s' for writing"), + fn); + GNUNET_DISK_file_close (fh); + dr->state = BRS_ERROR; + pi.status = GNUNET_FS_STATUS_DOWNLOAD_ERROR; + pi.value.download.specifics.error.message = dc->emsg; + GNUNET_FS_download_make_status_ (&pi, dc); + return; + } + GNUNET_DISK_file_close (fh); + /* signal success */ + dr->state = BRS_DOWNLOAD_UP; + dc->completed = dc->length; + GNUNET_FS_download_sync_ (dc); + pi.status = GNUNET_FS_STATUS_DOWNLOAD_PROGRESS; + pi.value.download.specifics.progress.data = data; + pi.value.download.specifics.progress.offset = 0; + pi.value.download.specifics.progress.data_len = dlen; + pi.value.download.specifics.progress.depth = 0; + pi.value.download.specifics.progress.trust_offered = 0; + GNUNET_FS_download_make_status_ (&pi, dc); + if ((NULL != dc->filename) && + (0 != + truncate (dc->filename, + GNUNET_ntohll (dc->uri->data.chk.file_length)))) + GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING, "truncate", + dc->filename); + check_completed (dc); + break; + default: + /* how did we get here? */ + GNUNET_break (0); + break; + } +} + + +/** + * Type of a function that libextractor calls for each + * meta data item found. If we find full data meta data, + * call 'try_match_block' on it. + * + * @param cls our 'struct GNUNET_FS_DownloadContext*' + * @param plugin_name name of the plugin that produced this value; + * special values can be used (i.e. '<zlib>' for zlib being + * used in the main libextractor library and yielding + * meta data). + * @param type libextractor-type describing the meta data + * @param format basic format information about data + * @param data_mime_type mime-type of data (not of the original file); + * can be NULL (if mime-type is not known) + * @param data actual meta-data found + * @param data_len number of bytes in data + * @return 0 to continue extracting, 1 to abort + */ +static int +match_full_data (void *cls, const char *plugin_name, + enum EXTRACTOR_MetaType type, enum EXTRACTOR_MetaFormat format, + const char *data_mime_type, const char *data, size_t data_len) +{ + struct GNUNET_FS_DownloadContext *dc = cls; + + if (type != EXTRACTOR_METATYPE_GNUNET_FULL_DATA) + return 0; + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Found %u bytes of FD!\n", + (unsigned int) data_len); + if (GNUNET_FS_uri_chk_get_file_size (dc->uri) != data_len) + { + GNUNET_break_op (0); + return 1; /* bogus meta data */ + } + try_match_block (dc, dc->top_request, data, data_len); + return 1; +} + + +/** + * Set the state of the given download request to + * BRS_DOWNLOAD_UP and propagate it up the tree. + * + * @param dr download request that is done + */ +static void +propagate_up (struct DownloadRequest *dr) +{ + unsigned int i; + + do + { + dr->state = BRS_DOWNLOAD_UP; + dr = dr->parent; + if (dr == NULL) + break; + for (i = 0; i < dr->num_children; i++) + if (dr->children[i]->state != BRS_DOWNLOAD_UP) + break; + } + while (i == dr->num_children); +} + + +/** + * Try top-down reconstruction. Before, the given request node + * must have the state BRS_CHK_SET. Afterwards, more nodes may + * have that state or advanced to BRS_DOWNLOAD_DOWN or even + * BRS_DOWNLOAD_UP. It is also possible to get BRS_ERROR on the + * top level. + * + * @param dc overall download this block belongs to + * @param dr block to reconstruct + */ +static void +try_top_down_reconstruction (struct GNUNET_FS_DownloadContext *dc, + struct DownloadRequest *dr) +{ + uint64_t off; + char block[DBLOCK_SIZE]; + GNUNET_HashCode key; + uint64_t total; + size_t len; + unsigned int i; + unsigned int chk_off; + struct DownloadRequest *drc; + uint64_t child_block_size; + const struct ContentHashKey *chks; + int up_done; + + GNUNET_assert (dc->rfh != NULL); + GNUNET_assert (dr->state == BRS_CHK_SET); + total = GNUNET_FS_uri_chk_get_file_size (dc->uri); + GNUNET_assert (dr->depth < dc->treedepth); + len = GNUNET_FS_tree_calculate_block_size (total, dr->offset, dr->depth); + GNUNET_assert (len <= DBLOCK_SIZE); + off = compute_disk_offset (total, dr->offset, dr->depth); + if (dc->old_file_size < off + len) + return; /* failure */ + if (off != GNUNET_DISK_file_seek (dc->rfh, off, GNUNET_DISK_SEEK_SET)) + { + GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING, "seek", dc->filename); + return; /* failure */ + } + if (len != GNUNET_DISK_file_read (dc->rfh, block, len)) + { + GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING, "read", dc->filename); + return; /* failure */ + } + GNUNET_CRYPTO_hash (block, len, &key); + if (0 != memcmp (&key, &dr->chk.key, sizeof (GNUNET_HashCode))) + return; /* mismatch */ + if (GNUNET_OK != + encrypt_existing_match (dc, &dr->chk, dr, block, len, GNUNET_NO)) + { + /* hash matches but encrypted block does not, really bad */ + dr->state = BRS_ERROR; + /* propagate up */ + while (dr->parent != NULL) + { + dr = dr->parent; + dr->state = BRS_ERROR; + } + return; + } + /* block matches */ + dr->state = BRS_DOWNLOAD_DOWN; + + /* set CHKs for children */ + up_done = GNUNET_YES; + chks = (const struct ContentHashKey *) block; + for (i = 0; i < dr->num_children; i++) + { + drc = dr->children[i]; + GNUNET_assert (drc->offset >= dr->offset); + child_block_size = GNUNET_FS_tree_compute_tree_size (drc->depth); + GNUNET_assert (0 == (drc->offset - dr->offset) % child_block_size); + chk_off = (drc->offset - dr->offset) / child_block_size; + if (drc->state == BRS_INIT) + { + drc->state = BRS_CHK_SET; + drc->chk = chks[chk_off]; + try_top_down_reconstruction (dc, drc); + } + if (drc->state != BRS_DOWNLOAD_UP) + up_done = GNUNET_NO; /* children not all done */ + } + if (up_done == GNUNET_YES) + propagate_up (dr); /* children all done (or no children...) */ +} + + +/** + * Schedule the download of the specified block in the tree. + * + * @param dc overall download this block belongs to + * @param dr request to schedule + */ +static void +schedule_block_download (struct GNUNET_FS_DownloadContext *dc, + struct DownloadRequest *dr) +{ + unsigned int i; + + switch (dr->state) + { + case BRS_INIT: + GNUNET_assert (0); + break; + case BRS_RECONSTRUCT_DOWN: + GNUNET_assert (0); + break; + case BRS_RECONSTRUCT_META_UP: + GNUNET_assert (0); + break; + case BRS_RECONSTRUCT_UP: + GNUNET_assert (0); + break; + case BRS_CHK_SET: + /* normal case, start download */ + break; + case BRS_DOWNLOAD_DOWN: + for (i = 0; i < dr->num_children; i++) + schedule_block_download (dc, dr->children[i]); + return; + case BRS_DOWNLOAD_UP: + /* We're done! */ + return; + case BRS_ERROR: + GNUNET_break (0); + return; + } + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Scheduling download at offset %llu and depth %u for `%s'\n", + (unsigned long long) dr->offset, dr->depth, + GNUNET_h2s (&dr->chk.query)); + if (GNUNET_NO != + GNUNET_CONTAINER_multihashmap_contains_value (dc->active, &dr->chk.query, + dr)) + return; /* already active */ + GNUNET_CONTAINER_multihashmap_put (dc->active, &dr->chk.query, dr, + GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE); + if (dc->client == NULL) + return; /* download not active */ + GNUNET_CONTAINER_DLL_insert (dc->pending_head, dc->pending_tail, dr); + dr->is_pending = GNUNET_YES; + if (NULL == dc->th) + dc->th = + GNUNET_CLIENT_notify_transmit_ready (dc->client, + sizeof (struct SearchMessage), + GNUNET_CONSTANTS_SERVICE_TIMEOUT, + GNUNET_NO, + &transmit_download_request, dc); +} + + +#define GNUNET_FS_URI_CHK_PREFIX GNUNET_FS_URI_PREFIX GNUNET_FS_URI_CHK_INFIX + +/** + * We found an entry in a directory. Check if the respective child + * already exists and if not create the respective child download. + * + * @param cls the parent download + * @param filename name of the file in the directory + * @param uri URI of the file (CHK or LOC) + * @param meta meta data of the file + * @param length number of bytes in data + * @param data contents of the file (or NULL if they were not inlined) + */ +static void +trigger_recursive_download (void *cls, const char *filename, + const struct GNUNET_FS_Uri *uri, + const struct GNUNET_CONTAINER_MetaData *meta, + size_t length, const void *data) +{ + struct GNUNET_FS_DownloadContext *dc = cls; + struct GNUNET_FS_DownloadContext *cpos; + char *temp_name; + char *fn; + char *us; + char *ext; + char *dn; + char *pos; + char *full_name; + char *sfn; + + if (NULL == uri) + return; /* entry for the directory itself */ + cpos = dc->child_head; + while (cpos != NULL) + { + if ((GNUNET_FS_uri_test_equal (uri, cpos->uri)) || + ((filename != NULL) && (0 == strcmp (cpos->filename, filename)))) + break; + cpos = cpos->next; + } + if (cpos != NULL) + return; /* already exists */ + fn = NULL; + if (NULL == filename) + { + fn = GNUNET_FS_meta_data_suggest_filename (meta); + if (fn == NULL) + { + us = GNUNET_FS_uri_to_string (uri); + fn = GNUNET_strdup (&us[strlen (GNUNET_FS_URI_CHK_PREFIX)]); + GNUNET_free (us); + } + else if (fn[0] == '.') + { + ext = fn; + us = GNUNET_FS_uri_to_string (uri); + GNUNET_asprintf (&fn, "%s%s", &us[strlen (GNUNET_FS_URI_CHK_PREFIX)], + ext); + GNUNET_free (ext); + GNUNET_free (us); + } + /* change '\' to '/' (this should have happened + * during insertion, but malicious peers may + * not have done this) */ + while (NULL != (pos = strstr (fn, "\\"))) + *pos = '/'; + /* remove '../' everywhere (again, well-behaved + * peers don't do this, but don't trust that + * we did not get something nasty) */ + while (NULL != (pos = strstr (fn, "../"))) + { + pos[0] = '_'; + pos[1] = '_'; + pos[2] = '_'; + } + filename = fn; + } + if (dc->filename == NULL) + { + full_name = NULL; + } + else + { + dn = GNUNET_strdup (dc->filename); + GNUNET_break ((strlen (dn) >= strlen (GNUNET_FS_DIRECTORY_EXT)) && + (NULL != + strstr (dn + strlen (dn) - strlen (GNUNET_FS_DIRECTORY_EXT), + GNUNET_FS_DIRECTORY_EXT))); + sfn = GNUNET_strdup (filename); + while ((strlen (sfn) > 0) && (filename[strlen (sfn) - 1] == '/')) + sfn[strlen (sfn) - 1] = '\0'; + if ((strlen (dn) >= strlen (GNUNET_FS_DIRECTORY_EXT)) && + (NULL != + strstr (dn + strlen (dn) - strlen (GNUNET_FS_DIRECTORY_EXT), + GNUNET_FS_DIRECTORY_EXT))) + dn[strlen (dn) - strlen (GNUNET_FS_DIRECTORY_EXT)] = '\0'; + if ((GNUNET_YES == GNUNET_FS_meta_data_test_for_directory (meta)) && + ((strlen (filename) < strlen (GNUNET_FS_DIRECTORY_EXT)) || + (NULL == + strstr (filename + strlen (filename) - + strlen (GNUNET_FS_DIRECTORY_EXT), GNUNET_FS_DIRECTORY_EXT)))) + { + GNUNET_asprintf (&full_name, "%s%s%s%s", dn, DIR_SEPARATOR_STR, sfn, + GNUNET_FS_DIRECTORY_EXT); + } + else + { + GNUNET_asprintf (&full_name, "%s%s%s", dn, DIR_SEPARATOR_STR, sfn); + } + GNUNET_free (sfn); + GNUNET_free (dn); + } + if ((full_name != NULL) && + (GNUNET_OK != GNUNET_DISK_directory_create_for_file (full_name))) + { + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + _ + ("Failed to create directory for recursive download of `%s'\n"), + full_name); + GNUNET_free (full_name); + GNUNET_free_non_null (fn); + return; + } + + temp_name = NULL; + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Triggering recursive download of size %llu with %u bytes MD\n", + (unsigned long long) GNUNET_FS_uri_chk_get_file_size (uri), + (unsigned int) + GNUNET_CONTAINER_meta_data_get_serialized_size (meta)); + GNUNET_FS_download_start (dc->h, uri, meta, full_name, temp_name, 0, + GNUNET_FS_uri_chk_get_file_size (uri), + dc->anonymity, dc->options, NULL, dc); + GNUNET_free_non_null (full_name); + GNUNET_free_non_null (temp_name); + GNUNET_free_non_null (fn); +} + + +/** + * (recursively) free download request structure + * + * @param dr request to free + */ +void +GNUNET_FS_free_download_request_ (struct DownloadRequest *dr) +{ + unsigned int i; + + if (dr == NULL) + return; + for (i = 0; i < dr->num_children; i++) + GNUNET_FS_free_download_request_ (dr->children[i]); + GNUNET_free_non_null (dr->children); + GNUNET_free (dr); +} + + +/** + * Iterator over entries in the pending requests in the 'active' map for the + * reply that we just got. + * + * @param cls closure (our 'struct ProcessResultClosure') + * @param key query for the given value / request + * @param value value in the hash map (a 'struct DownloadRequest') + * @return GNUNET_YES (we should continue to iterate); unless serious error + */ +static int +process_result_with_request (void *cls, const GNUNET_HashCode * key, + void *value) +{ + struct ProcessResultClosure *prc = cls; + struct DownloadRequest *dr = value; + struct GNUNET_FS_DownloadContext *dc = prc->dc; + struct DownloadRequest *drc; + struct GNUNET_DISK_FileHandle *fh = NULL; + struct GNUNET_CRYPTO_AesSessionKey skey; + struct GNUNET_CRYPTO_AesInitializationVector iv; + char pt[prc->size]; + struct GNUNET_FS_ProgressInfo pi; + uint64_t off; + size_t bs; + size_t app; + int i; + struct ContentHashKey *chkarr; + + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Received block `%s' matching pending request at depth %u and offset %llu/%llu\n", + GNUNET_h2s (key), dr->depth, (unsigned long long) dr->offset, + (unsigned long long) GNUNET_ntohll (dc->uri->data. + chk.file_length)); + bs = GNUNET_FS_tree_calculate_block_size (GNUNET_ntohll + (dc->uri->data.chk.file_length), + dr->offset, dr->depth); + if (prc->size != bs) + { + GNUNET_asprintf (&dc->emsg, + _ + ("Internal error or bogus download URI (expected %u bytes at depth %u and offset %llu/%llu, got %u bytes)\n"), + bs, dr->depth, (unsigned long long) dr->offset, + (unsigned long long) GNUNET_ntohll (dc->uri->data. + chk.file_length), + prc->size); + GNUNET_log (GNUNET_ERROR_TYPE_WARNING, "%s", dc->emsg); + while (dr->parent != NULL) + { + dr->state = BRS_ERROR; + dr = dr->parent; + } + dr->state = BRS_ERROR; + goto signal_error; + } + + (void) GNUNET_CONTAINER_multihashmap_remove (dc->active, &prc->query, dr); + if (GNUNET_YES == dr->is_pending) + { + GNUNET_CONTAINER_DLL_remove (dc->pending_head, dc->pending_tail, dr); + dr->is_pending = GNUNET_NO; + } + + GNUNET_CRYPTO_hash_to_aes_key (&dr->chk.key, &skey, &iv); + if (-1 == GNUNET_CRYPTO_aes_decrypt (prc->data, prc->size, &skey, &iv, pt)) + { + GNUNET_break (0); + dc->emsg = GNUNET_strdup (_("internal error decrypting content")); + goto signal_error; + } + off = + compute_disk_offset (GNUNET_ntohll (dc->uri->data.chk.file_length), + dr->offset, dr->depth); + /* save to disk */ + if ((GNUNET_YES == prc->do_store) && + ((dc->filename != NULL) || (is_recursive_download (dc))) && + ((dr->depth == dc->treedepth) || + (0 == (dc->options & GNUNET_FS_DOWNLOAD_NO_TEMPORARIES)))) + { + fh = GNUNET_DISK_file_open (dc->filename != + NULL ? dc->filename : dc->temp_filename, + GNUNET_DISK_OPEN_READWRITE | + GNUNET_DISK_OPEN_CREATE, + GNUNET_DISK_PERM_USER_READ | + GNUNET_DISK_PERM_USER_WRITE | + GNUNET_DISK_PERM_GROUP_READ | + GNUNET_DISK_PERM_OTHER_READ); + if (NULL == fh) + { + GNUNET_asprintf (&dc->emsg, + _("Download failed: could not open file `%s': %s\n"), + dc->filename, STRERROR (errno)); + goto signal_error; + } + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Saving decrypted block to disk at offset %llu\n", + (unsigned long long) off); + if ((off != GNUNET_DISK_file_seek (fh, off, GNUNET_DISK_SEEK_SET))) + { + GNUNET_asprintf (&dc->emsg, + _("Failed to seek to offset %llu in file `%s': %s\n"), + (unsigned long long) off, dc->filename, + STRERROR (errno)); + goto signal_error; + } + if (prc->size != GNUNET_DISK_file_write (fh, pt, prc->size)) + { + GNUNET_asprintf (&dc->emsg, + _ + ("Failed to write block of %u bytes at offset %llu in file `%s': %s\n"), + (unsigned int) prc->size, (unsigned long long) off, + dc->filename, STRERROR (errno)); + goto signal_error; + } + GNUNET_break (GNUNET_OK == GNUNET_DISK_file_close (fh)); + fh = NULL; + } + + if (dr->depth == 0) + { + /* DBLOCK, update progress and try recursion if applicable */ + app = prc->size; + if (dr->offset < dc->offset) + { + /* starting offset begins in the middle of pt, + * do not count first bytes as progress */ + GNUNET_assert (app > (dc->offset - dr->offset)); + app -= (dc->offset - dr->offset); + } + if (dr->offset + prc->size > dc->offset + dc->length) + { + /* end of block is after relevant range, + * do not count last bytes as progress */ + GNUNET_assert (app > + (dr->offset + prc->size) - (dc->offset + dc->length)); + app -= (dr->offset + prc->size) - (dc->offset + dc->length); + } + dc->completed += app; + + /* do recursive download if option is set and either meta data + * says it is a directory or if no meta data is given AND filename + * ends in '.gnd' (top-level case) */ + if (is_recursive_download (dc)) + GNUNET_FS_directory_list_contents (prc->size, pt, off, + &trigger_recursive_download, dc); + + } + GNUNET_assert (dc->completed <= dc->length); + dr->state = BRS_DOWNLOAD_DOWN; + pi.status = GNUNET_FS_STATUS_DOWNLOAD_PROGRESS; + pi.value.download.specifics.progress.data = pt; + pi.value.download.specifics.progress.offset = dr->offset; + pi.value.download.specifics.progress.data_len = prc->size; + pi.value.download.specifics.progress.depth = dr->depth; + pi.value.download.specifics.progress.trust_offered = 0; + if (prc->last_transmission.abs_value != GNUNET_TIME_UNIT_FOREVER_ABS.abs_value) + pi.value.download.specifics.progress.block_download_duration = + GNUNET_TIME_absolute_get_duration (prc->last_transmission); + else + pi.value.download.specifics.progress.block_download_duration.rel_value = + GNUNET_TIME_UNIT_FOREVER_REL.rel_value; + GNUNET_FS_download_make_status_ (&pi, dc); + if (dr->depth == 0) + propagate_up (dr); + + if (dc->completed == dc->length) + { + /* download completed, signal */ + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Download completed, truncating file to desired length %llu\n", + (unsigned long long) GNUNET_ntohll (dc->uri->data. + chk.file_length)); + /* truncate file to size (since we store IBlocks at the end) */ + if (dc->filename != NULL) + { + if (0 != + truncate (dc->filename, + GNUNET_ntohll (dc->uri->data.chk.file_length))) + GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING, "truncate", + dc->filename); + } + GNUNET_assert (dr->depth == 0); + check_completed (dc); + } + if (dr->depth == 0) + { + /* bottom of the tree, no child downloads possible, just sync */ + GNUNET_FS_download_sync_ (dc); + return GNUNET_YES; + } + + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Triggering downloads of children (this block was at depth %u and offset %llu)\n", + dr->depth, (unsigned long long) dr->offset); + GNUNET_assert (0 == (prc->size % sizeof (struct ContentHashKey))); + chkarr = (struct ContentHashKey *) pt; + for (i = (prc->size / sizeof (struct ContentHashKey)) - 1; i >= 0; i--) + { + drc = dr->children[i]; + switch (drc->state) + { + case BRS_INIT: + drc->chk = chkarr[i]; + drc->state = BRS_CHK_SET; + schedule_block_download (dc, drc); + break; + case BRS_RECONSTRUCT_DOWN: + GNUNET_assert (0); + break; + case BRS_RECONSTRUCT_META_UP: + GNUNET_assert (0); + break; + case BRS_RECONSTRUCT_UP: + GNUNET_assert (0); + break; + case BRS_CHK_SET: + GNUNET_assert (0); + break; + case BRS_DOWNLOAD_DOWN: + GNUNET_assert (0); + break; + case BRS_DOWNLOAD_UP: + GNUNET_assert (0); + break; + case BRS_ERROR: + GNUNET_assert (0); + break; + default: + GNUNET_assert (0); + break; + } + } + GNUNET_FS_download_sync_ (dc); + return GNUNET_YES; + +signal_error: + if (fh != NULL) + GNUNET_DISK_file_close (fh); + pi.status = GNUNET_FS_STATUS_DOWNLOAD_ERROR; + pi.value.download.specifics.error.message = dc->emsg; + GNUNET_FS_download_make_status_ (&pi, dc); + /* abort all pending requests */ + if (NULL != dc->th) + { + GNUNET_CLIENT_notify_transmit_ready_cancel (dc->th); + dc->th = NULL; + } + GNUNET_CLIENT_disconnect (dc->client, GNUNET_NO); + dc->in_receive = GNUNET_NO; + dc->client = NULL; + GNUNET_FS_free_download_request_ (dc->top_request); + dc->top_request = NULL; + GNUNET_CONTAINER_multihashmap_destroy (dc->active); + dc->active = NULL; + dc->pending_head = NULL; + dc->pending_tail = NULL; + GNUNET_FS_download_sync_ (dc); + return GNUNET_NO; +} + + +/** + * Process a download result. + * + * @param dc our download context + * @param type type of the result + * @param last_transmission when was this block requested the last time? (FOREVER if unknown/not applicable) + * @param data the (encrypted) response + * @param size size of data + */ +static void +process_result (struct GNUNET_FS_DownloadContext *dc, + enum GNUNET_BLOCK_Type type, + struct GNUNET_TIME_Absolute last_transmission, + const void *data, size_t size) +{ + struct ProcessResultClosure prc; + + prc.dc = dc; + prc.data = data; + prc.size = size; + prc.type = type; + prc.do_store = GNUNET_YES; + prc.last_transmission = last_transmission; + GNUNET_CRYPTO_hash (data, size, &prc.query); + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Received result for query `%s' from `%s'-service\n", + GNUNET_h2s (&prc.query), "FS"); + GNUNET_CONTAINER_multihashmap_get_multiple (dc->active, &prc.query, + &process_result_with_request, + &prc); +} + + +/** + * Type of a function to call when we receive a message + * from the service. + * + * @param cls closure + * @param msg message received, NULL on timeout or fatal error + */ +static void +receive_results (void *cls, const struct GNUNET_MessageHeader *msg) +{ + struct GNUNET_FS_DownloadContext *dc = cls; + const struct ClientPutMessage *cm; + uint16_t msize; + + if ((NULL == msg) || (ntohs (msg->type) != GNUNET_MESSAGE_TYPE_FS_PUT) || + (sizeof (struct ClientPutMessage) > ntohs (msg->size))) + { + GNUNET_break (msg == NULL); + try_reconnect (dc); + return; + } + msize = ntohs (msg->size); + cm = (const struct ClientPutMessage *) msg; + process_result (dc, ntohl (cm->type), + GNUNET_TIME_absolute_ntoh (cm->last_transmission), &cm[1], + msize - sizeof (struct ClientPutMessage)); + if (dc->client == NULL) + return; /* fatal error */ + /* continue receiving */ + GNUNET_CLIENT_receive (dc->client, &receive_results, dc, + GNUNET_TIME_UNIT_FOREVER_REL); +} + + + +/** + * We're ready to transmit a search request to the + * file-sharing service. Do it. If there is + * more than one request pending, try to send + * multiple or request another transmission. + * + * @param cls closure + * @param size number of bytes available in buf + * @param buf where the callee should write the message + * @return number of bytes written to buf + */ +static size_t +transmit_download_request (void *cls, size_t size, void *buf) +{ + struct GNUNET_FS_DownloadContext *dc = cls; + size_t msize; + struct SearchMessage *sm; + struct DownloadRequest *dr; + + dc->th = NULL; + if (NULL == buf) + { + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Transmitting download request failed, trying to reconnect\n"); + try_reconnect (dc); + return 0; + } + GNUNET_assert (size >= sizeof (struct SearchMessage)); + msize = 0; + sm = buf; + while ((NULL != (dr = dc->pending_head)) && + (size >= msize + sizeof (struct SearchMessage))) + { + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Transmitting download request for `%s' to `%s'-service\n", + GNUNET_h2s (&dr->chk.query), "FS"); + memset (sm, 0, sizeof (struct SearchMessage)); + sm->header.size = htons (sizeof (struct SearchMessage)); + sm->header.type = htons (GNUNET_MESSAGE_TYPE_FS_START_SEARCH); + if (0 != (dc->options & GNUNET_FS_DOWNLOAD_OPTION_LOOPBACK_ONLY)) + sm->options = htonl (GNUNET_FS_SEARCH_OPTION_LOOPBACK_ONLY); + else + sm->options = htonl (GNUNET_FS_SEARCH_OPTION_NONE); + if (dr->depth == 0) + sm->type = htonl (GNUNET_BLOCK_TYPE_FS_DBLOCK); + else + sm->type = htonl (GNUNET_BLOCK_TYPE_FS_IBLOCK); + sm->anonymity_level = htonl (dc->anonymity); + sm->target = dc->target.hashPubKey; + sm->query = dr->chk.query; + GNUNET_CONTAINER_DLL_remove (dc->pending_head, dc->pending_tail, dr); + dr->is_pending = GNUNET_NO; + msize += sizeof (struct SearchMessage); + sm++; + } + if (dc->pending_head != NULL) + { + dc->th = + GNUNET_CLIENT_notify_transmit_ready (dc->client, + sizeof (struct SearchMessage), + GNUNET_CONSTANTS_SERVICE_TIMEOUT, + GNUNET_NO, + &transmit_download_request, dc); + GNUNET_assert (dc->th != NULL); + } + if (GNUNET_NO == dc->in_receive) + { + dc->in_receive = GNUNET_YES; + GNUNET_CLIENT_receive (dc->client, &receive_results, dc, + GNUNET_TIME_UNIT_FOREVER_REL); + } + return msize; +} + + +/** + * Reconnect to the FS service and transmit our queries NOW. + * + * @param cls our download context + * @param tc unused + */ +static void +do_reconnect (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) +{ + struct GNUNET_FS_DownloadContext *dc = cls; + struct GNUNET_CLIENT_Connection *client; + + dc->task = GNUNET_SCHEDULER_NO_TASK; + client = GNUNET_CLIENT_connect ("fs", dc->h->cfg); + if (NULL == client) + { + GNUNET_log (GNUNET_ERROR_TYPE_WARNING, + "Connecting to `%s'-service failed, will try again.\n", "FS"); + try_reconnect (dc); + return; + } + dc->client = client; + if (dc->pending_head != NULL) + { + dc->th = + GNUNET_CLIENT_notify_transmit_ready (client, + sizeof (struct SearchMessage), + GNUNET_CONSTANTS_SERVICE_TIMEOUT, + GNUNET_NO, + &transmit_download_request, dc); + GNUNET_assert (dc->th != NULL); + } +} + + +/** + * Add entries to the pending list. + * + * @param cls our download context + * @param key unused + * @param entry entry of type "struct DownloadRequest" + * @return GNUNET_OK + */ +static int +retry_entry (void *cls, const GNUNET_HashCode * key, void *entry) +{ + struct GNUNET_FS_DownloadContext *dc = cls; + struct DownloadRequest *dr = entry; + + dr->next = NULL; + dr->prev = NULL; + GNUNET_CONTAINER_DLL_insert (dc->pending_head, dc->pending_tail, dr); + dr->is_pending = GNUNET_YES; + return GNUNET_OK; +} + + +/** + * We've lost our connection with the FS service. + * Re-establish it and re-transmit all of our + * pending requests. + * + * @param dc download context that is having trouble + */ +static void +try_reconnect (struct GNUNET_FS_DownloadContext *dc) +{ + + if (NULL != dc->client) + { + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Moving all requests back to pending list\n"); + if (NULL != dc->th) + { + GNUNET_CLIENT_notify_transmit_ready_cancel (dc->th); + dc->th = NULL; + } + /* full reset of the pending list */ + dc->pending_head = NULL; + dc->pending_tail = NULL; + GNUNET_CONTAINER_multihashmap_iterate (dc->active, &retry_entry, dc); + GNUNET_CLIENT_disconnect (dc->client, GNUNET_NO); + dc->in_receive = GNUNET_NO; + dc->client = NULL; + } + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Will try to reconnect in 1s\n"); + dc->task = + GNUNET_SCHEDULER_add_delayed (GNUNET_TIME_UNIT_SECONDS, &do_reconnect, + dc); +} + + +/** + * We're allowed to ask the FS service for our blocks. Start the download. + * + * @param cls the 'struct GNUNET_FS_DownloadContext' + * @param client handle to use for communcation with FS (we must destroy it!) + */ +static void +activate_fs_download (void *cls, struct GNUNET_CLIENT_Connection *client) +{ + struct GNUNET_FS_DownloadContext *dc = cls; + struct GNUNET_FS_ProgressInfo pi; + + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Download activated\n"); + GNUNET_assert (NULL != client); + GNUNET_assert (dc->client == NULL); + GNUNET_assert (dc->th == NULL); + dc->client = client; + pi.status = GNUNET_FS_STATUS_DOWNLOAD_ACTIVE; + GNUNET_FS_download_make_status_ (&pi, dc); + dc->pending_head = NULL; + dc->pending_tail = NULL; + GNUNET_CONTAINER_multihashmap_iterate (dc->active, &retry_entry, dc); + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Asking for transmission to FS service\n"); + if (dc->pending_head != NULL) + { + dc->th = + GNUNET_CLIENT_notify_transmit_ready (dc->client, + sizeof (struct SearchMessage), + GNUNET_CONSTANTS_SERVICE_TIMEOUT, + GNUNET_NO, + &transmit_download_request, dc); + GNUNET_assert (dc->th != NULL); + } +} + + +/** + * We must stop to ask the FS service for our blocks. Pause the download. + * + * @param cls the 'struct GNUNET_FS_DownloadContext' + */ +static void +deactivate_fs_download (void *cls) +{ + struct GNUNET_FS_DownloadContext *dc = cls; + struct GNUNET_FS_ProgressInfo pi; + + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Download deactivated\n"); + if (NULL != dc->th) + { + GNUNET_CLIENT_notify_transmit_ready_cancel (dc->th); + dc->th = NULL; + } + if (NULL != dc->client) + { + GNUNET_CLIENT_disconnect (dc->client, GNUNET_NO); + dc->in_receive = GNUNET_NO; + dc->client = NULL; + } + dc->pending_head = NULL; + dc->pending_tail = NULL; + pi.status = GNUNET_FS_STATUS_DOWNLOAD_INACTIVE; + GNUNET_FS_download_make_status_ (&pi, dc); +} + + +/** + * (recursively) Create a download request structure. + * + * @param parent parent of the current entry + * @param depth depth of the current entry, 0 are the DBLOCKs, + * top level block is 'dc->treedepth - 1' + * @param dr_offset offset in the original file this block maps to + * (as in, offset of the first byte of the first DBLOCK + * in the subtree rooted in the returned download request tree) + * @param file_start_offset desired starting offset for the download + * in the original file; requesting tree should not contain + * DBLOCKs prior to the file_start_offset + * @param desired_length desired number of bytes the user wanted to access + * (from file_start_offset). Resulting tree should not contain + * DBLOCKs after file_start_offset + file_length. + * @return download request tree for the given range of DBLOCKs at + * the specified depth + */ +static struct DownloadRequest * +create_download_request (struct DownloadRequest *parent, unsigned int depth, + uint64_t dr_offset, uint64_t file_start_offset, + uint64_t desired_length) +{ + struct DownloadRequest *dr; + unsigned int i; + unsigned int head_skip; + uint64_t child_block_size; + + dr = GNUNET_malloc (sizeof (struct DownloadRequest)); + dr->parent = parent; + dr->depth = depth; + dr->offset = dr_offset; + if (depth > 0) + { + child_block_size = GNUNET_FS_tree_compute_tree_size (depth - 1); + + /* calculate how many blocks at this level are not interesting + * from the start (rounded down), either because of the requested + * file offset or because this IBlock is further along */ + if (dr_offset < file_start_offset) + head_skip = file_start_offset / child_block_size; + else + head_skip = dr_offset / child_block_size; + + /* calculate index of last block at this level that is interesting (rounded up) */ + dr->num_children = file_start_offset + desired_length / child_block_size; + if (dr->num_children * child_block_size < + file_start_offset + desired_length) + dr->num_children++; /* round up */ + + /* now we can get the total number of children for this block */ + dr->num_children -= head_skip; + if (dr->num_children > CHK_PER_INODE) + dr->num_children = CHK_PER_INODE; /* cap at max */ + + /* why else would we have gotten here to begin with? (that'd be a bad logic error) */ + GNUNET_assert (dr->num_children > 0); + + dr->children = + GNUNET_malloc (dr->num_children * sizeof (struct DownloadRequest *)); + for (i = 0; i < dr->num_children; i++) + dr->children[i] = + create_download_request (dr, depth - 1, + dr_offset + i * child_block_size, + file_start_offset, desired_length); + } + return dr; +} + + +/** + * Continuation after a possible attempt to reconstruct + * the current IBlock from the existing file. + * + * @param cls the 'struct ReconstructContext' + * @param tc scheduler context + */ +static void +reconstruct_cont (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) +{ + struct GNUNET_FS_DownloadContext *dc = cls; + + /* clean up state from tree encoder */ + if (dc->te != NULL) + { + GNUNET_FS_tree_encoder_finish (dc->te, NULL, NULL); + dc->te = NULL; + } + if (dc->task != GNUNET_SCHEDULER_NO_TASK) + { + GNUNET_SCHEDULER_cancel (dc->task); + dc->task = GNUNET_SCHEDULER_NO_TASK; + } + if (dc->rfh != NULL) + { + GNUNET_break (GNUNET_OK == GNUNET_DISK_file_close (dc->rfh)); + dc->rfh = NULL; + } + /* start "normal" download */ + schedule_block_download (dc, dc->top_request); +} + + +/** + * Task requesting the next block from the tree encoder. + * + * @param cls the 'struct GNUJNET_FS_DownloadContext' we're processing + * @param tc task context + */ +static void +get_next_block (void *cls, const struct GNUNET_SCHEDULER_TaskContext *tc) +{ + struct GNUNET_FS_DownloadContext *dc = cls; + + dc->task = GNUNET_SCHEDULER_NO_TASK; + GNUNET_FS_tree_encoder_next (dc->te); +} + + + +/** + * Function called asking for the current (encoded) + * block to be processed. After processing the + * client should either call "GNUNET_FS_tree_encode_next" + * or (on error) "GNUNET_FS_tree_encode_finish". + * + * This function checks if the content on disk matches + * the expected content based on the URI. + * + * @param cls closure + * @param chk content hash key for the block + * @param offset offset of the block + * @param depth depth of the block, 0 for DBLOCK + * @param type type of the block (IBLOCK or DBLOCK) + * @param block the (encrypted) block + * @param block_size size of block (in bytes) + */ +static void +reconstruct_cb (void *cls, const struct ContentHashKey *chk, uint64_t offset, + unsigned int depth, enum GNUNET_BLOCK_Type type, + const void *block, uint16_t block_size) +{ + struct GNUNET_FS_DownloadContext *dc = cls; + struct GNUNET_FS_ProgressInfo pi; + struct DownloadRequest *dr; + uint64_t blen; + unsigned int chld; + + /* find corresponding request entry */ + dr = dc->top_request; + while (dr->depth > depth) + { + blen = GNUNET_FS_tree_compute_tree_size (dr->depth); + chld = (offset - dr->offset) / blen; + GNUNET_assert (chld < dr->num_children); + dr = dr->children[chld]; + } + /* FIXME: this code needs more testing and might + need to handle more states... */ + switch (dr->state) + { + case BRS_INIT: + break; + case BRS_RECONSTRUCT_DOWN: + break; + case BRS_RECONSTRUCT_META_UP: + break; + case BRS_RECONSTRUCT_UP: + break; + case BRS_CHK_SET: + if (0 == memcmp (chk, &dr->chk, sizeof (struct ContentHashKey))) + { + /* block matches, hence tree below matches; + * this request is done! */ + dr->state = BRS_DOWNLOAD_UP; + GNUNET_break (GNUNET_NO == + GNUNET_CONTAINER_multihashmap_remove (dc->active, &dr->chk.query, dr)); + if (GNUNET_YES == dr->is_pending) + { + GNUNET_break (0); /* how did we get here? */ + GNUNET_CONTAINER_DLL_remove (dc->pending_head, dc->pending_tail, dr); + dr->is_pending = GNUNET_NO; + } + /* calculate how many bytes of payload this block + * corresponds to */ + blen = GNUNET_FS_tree_compute_tree_size (dr->depth); + /* how many of those bytes are in the requested range? */ + blen = GNUNET_MIN (blen, dc->length + dc->offset - dr->offset); + /* signal progress */ + dc->completed += blen; + pi.status = GNUNET_FS_STATUS_DOWNLOAD_PROGRESS; + pi.value.download.specifics.progress.data = NULL; + pi.value.download.specifics.progress.offset = offset; + pi.value.download.specifics.progress.data_len = 0; + pi.value.download.specifics.progress.depth = 0; + pi.value.download.specifics.progress.trust_offered = 0; + GNUNET_FS_download_make_status_ (&pi, dc); + /* FIXME: duplicated code from 'process_result_with_request - refactor */ + if (dc->completed == dc->length) + { + /* download completed, signal */ + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Download completed, truncating file to desired length %llu\n", + (unsigned long long) GNUNET_ntohll (dc->uri->data. + chk.file_length)); + /* truncate file to size (since we store IBlocks at the end) */ + if (dc->filename != NULL) + { + if (0 != + truncate (dc->filename, + GNUNET_ntohll (dc->uri->data.chk.file_length))) + GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING, "truncate", + dc->filename); + } + } + } + break; + case BRS_DOWNLOAD_DOWN: + break; + case BRS_DOWNLOAD_UP: + break; + case BRS_ERROR: + break; + default: + GNUNET_assert (0); + break; + } + if ((dr == dc->top_request) && (dr->state == BRS_DOWNLOAD_UP)) + { + check_completed (dc); + return; + } + dc->task = GNUNET_SCHEDULER_add_now (&get_next_block, dc); +} + + +/** + * Function called by the tree encoder to obtain a block of plaintext + * data (for the lowest level of the tree). + * + * @param cls our 'struct ReconstructContext' + * @param offset identifies which block to get + * @param max (maximum) number of bytes to get; returning + * fewer will also cause errors + * @param buf where to copy the plaintext buffer + * @param emsg location to store an error message (on error) + * @return number of bytes copied to buf, 0 on error + */ +static size_t +fh_reader (void *cls, uint64_t offset, size_t max, void *buf, char **emsg) +{ + struct GNUNET_FS_DownloadContext *dc = cls; + struct GNUNET_DISK_FileHandle *fh = dc->rfh; + ssize_t ret; + + *emsg = NULL; + if (offset != GNUNET_DISK_file_seek (fh, offset, GNUNET_DISK_SEEK_SET)) + { + *emsg = GNUNET_strdup (strerror (errno)); + return 0; + } + ret = GNUNET_DISK_file_read (fh, buf, max); + if (ret < 0) + { + *emsg = GNUNET_strdup (strerror (errno)); + return 0; + } + return ret; +} + + +/** + * Task that creates the initial (top-level) download + * request for the file. + * + * @param cls the 'struct GNUNET_FS_DownloadContext' + * @param tc scheduler context + */ +void +GNUNET_FS_download_start_task_ (void *cls, + const struct GNUNET_SCHEDULER_TaskContext *tc) +{ + struct GNUNET_FS_DownloadContext *dc = cls; + struct GNUNET_FS_ProgressInfo pi; + struct GNUNET_DISK_FileHandle *fh; + + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Start task running...\n"); + dc->task = GNUNET_SCHEDULER_NO_TASK; + if (dc->length == 0) + { + /* no bytes required! */ + if (dc->filename != NULL) + { + fh = GNUNET_DISK_file_open (dc->filename, + GNUNET_DISK_OPEN_READWRITE | + GNUNET_DISK_OPEN_CREATE | + ((0 == + GNUNET_FS_uri_chk_get_file_size (dc->uri)) ? + GNUNET_DISK_OPEN_TRUNCATE : 0), + GNUNET_DISK_PERM_USER_READ | + GNUNET_DISK_PERM_USER_WRITE | + GNUNET_DISK_PERM_GROUP_READ | + GNUNET_DISK_PERM_OTHER_READ); + GNUNET_DISK_file_close (fh); + } + GNUNET_FS_download_sync_ (dc); + pi.status = GNUNET_FS_STATUS_DOWNLOAD_START; + pi.value.download.specifics.start.meta = dc->meta; + GNUNET_FS_download_make_status_ (&pi, dc); + check_completed (dc); + return; + } + if (dc->emsg != NULL) + return; + if (dc->top_request == NULL) + { + dc->top_request = + create_download_request (NULL, dc->treedepth - 1, 0, dc->offset, + dc->length); + dc->top_request->state = BRS_CHK_SET; + dc->top_request->chk = + (dc->uri->type == + chk) ? dc->uri->data.chk.chk : dc->uri->data.loc.fi.chk; + /* signal start */ + GNUNET_FS_download_sync_ (dc); + if (NULL != dc->search) + GNUNET_FS_search_result_sync_ (dc->search); + pi.status = GNUNET_FS_STATUS_DOWNLOAD_START; + pi.value.download.specifics.start.meta = dc->meta; + GNUNET_FS_download_make_status_ (&pi, dc); + } + GNUNET_FS_download_start_downloading_ (dc); + /* attempt reconstruction from disk */ + if (GNUNET_YES == GNUNET_DISK_file_test (dc->filename)) + dc->rfh = + GNUNET_DISK_file_open (dc->filename, GNUNET_DISK_OPEN_READ, + GNUNET_DISK_PERM_NONE); + if (dc->top_request->state == BRS_CHK_SET) + { + if (dc->rfh != NULL) + { + /* first, try top-down */ + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Trying top-down reconstruction for `%s'\n", dc->filename); + try_top_down_reconstruction (dc, dc->top_request); + switch (dc->top_request->state) + { + case BRS_CHK_SET: + break; /* normal */ + case BRS_DOWNLOAD_DOWN: + break; /* normal, some blocks already down */ + case BRS_DOWNLOAD_UP: + /* already done entirely, party! */ + if (dc->rfh != NULL) + { + /* avoid hanging on to file handle longer than + * necessary */ + GNUNET_DISK_file_close (dc->rfh); + dc->rfh = NULL; + } + return; + case BRS_ERROR: + GNUNET_asprintf (&dc->emsg, _("Invalid URI")); + GNUNET_FS_download_sync_ (dc); + pi.status = GNUNET_FS_STATUS_DOWNLOAD_ERROR; + pi.value.download.specifics.error.message = dc->emsg; + GNUNET_FS_download_make_status_ (&pi, dc); + return; + default: + GNUNET_assert (0); + break; + } + } + } + /* attempt reconstruction from meta data */ + if ((GNUNET_FS_uri_chk_get_file_size (dc->uri) <= MAX_INLINE_SIZE) && + (NULL != dc->meta)) + { + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Trying to find embedded meta data for download of size %llu with %u bytes MD\n", + (unsigned long long) GNUNET_FS_uri_chk_get_file_size (dc->uri), + (unsigned int) + GNUNET_CONTAINER_meta_data_get_serialized_size (dc->meta)); + GNUNET_CONTAINER_meta_data_iterate (dc->meta, &match_full_data, dc); + if (dc->top_request->state == BRS_DOWNLOAD_UP) + { + if (dc->rfh != NULL) + { + /* avoid hanging on to file handle longer than + * necessary */ + GNUNET_DISK_file_close (dc->rfh); + dc->rfh = NULL; + } + return; /* finished, status update was already done for us */ + } + } + if (dc->rfh != NULL) + { + /* finally, try bottom-up */ + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "Trying bottom-up reconstruction of file `%s'\n", dc->filename); + dc->te = + GNUNET_FS_tree_encoder_create (dc->h, dc->old_file_size, dc, &fh_reader, + &reconstruct_cb, NULL, + &reconstruct_cont); + dc->task = GNUNET_SCHEDULER_add_now (&get_next_block, dc); + } + else + { + /* simple, top-level download */ + schedule_block_download (dc, dc->top_request); + } + if (dc->top_request->state == BRS_DOWNLOAD_UP) + check_completed (dc); +} + + +/** + * Create SUSPEND event for the given download operation + * and then clean up our state (without stop signal). + * + * @param cls the 'struct GNUNET_FS_DownloadContext' to signal for + */ +void +GNUNET_FS_download_signal_suspend_ (void *cls) +{ + struct GNUNET_FS_DownloadContext *dc = cls; + struct GNUNET_FS_ProgressInfo pi; + + if (dc->top != NULL) + GNUNET_FS_end_top (dc->h, dc->top); + while (NULL != dc->child_head) + GNUNET_FS_download_signal_suspend_ (dc->child_head); + if (dc->search != NULL) + { + dc->search->download = NULL; + dc->search = NULL; + } + if (dc->job_queue != NULL) + { + GNUNET_FS_dequeue_ (dc->job_queue); + dc->job_queue = NULL; + } + if (dc->parent != NULL) + GNUNET_CONTAINER_DLL_remove (dc->parent->child_head, dc->parent->child_tail, + dc); + if (dc->task != GNUNET_SCHEDULER_NO_TASK) + { + GNUNET_SCHEDULER_cancel (dc->task); + dc->task = GNUNET_SCHEDULER_NO_TASK; + } + pi.status = GNUNET_FS_STATUS_DOWNLOAD_SUSPEND; + GNUNET_FS_download_make_status_ (&pi, dc); + if (dc->te != NULL) + { + GNUNET_FS_tree_encoder_finish (dc->te, NULL, NULL); + dc->te = NULL; + } + if (dc->rfh != NULL) + { + GNUNET_DISK_file_close (dc->rfh); + dc->rfh = NULL; + } + GNUNET_FS_free_download_request_ (dc->top_request); + if (dc->active != NULL) + { + GNUNET_CONTAINER_multihashmap_destroy (dc->active); + dc->active = NULL; + } + GNUNET_free_non_null (dc->filename); + GNUNET_CONTAINER_meta_data_destroy (dc->meta); + GNUNET_FS_uri_destroy (dc->uri); + GNUNET_free_non_null (dc->temp_filename); + GNUNET_free_non_null (dc->serialization); + GNUNET_free (dc); +} + + +/** + * Download parts of a file. Note that this will store + * the blocks at the respective offset in the given file. Also, the + * download is still using the blocking of the underlying FS + * encoding. As a result, the download may *write* outside of the + * given boundaries (if offset and length do not match the 32k FS + * block boundaries). <p> + * + * This function should be used to focus a download towards a + * particular portion of the file (optimization), not to strictly + * limit the download to exactly those bytes. + * + * @param h handle to the file sharing subsystem + * @param uri the URI of the file (determines what to download); CHK or LOC URI + * @param meta known metadata for the file (can be NULL) + * @param filename where to store the file, maybe NULL (then no file is + * created on disk and data must be grabbed from the callbacks) + * @param tempname where to store temporary file data, not used if filename is non-NULL; + * can be NULL (in which case we will pick a name if needed); the temporary file + * may already exist, in which case we will try to use the data that is there and + * if it is not what is desired, will overwrite it + * @param offset at what offset should we start the download (typically 0) + * @param length how many bytes should be downloaded starting at offset + * @param anonymity anonymity level to use for the download + * @param options various options + * @param cctx initial value for the client context for this download + * @param parent parent download to associate this download with (use NULL + * for top-level downloads; useful for manually-triggered recursive downloads) + * @return context that can be used to control this download + */ +struct GNUNET_FS_DownloadContext * +GNUNET_FS_download_start (struct GNUNET_FS_Handle *h, + const struct GNUNET_FS_Uri *uri, + const struct GNUNET_CONTAINER_MetaData *meta, + const char *filename, const char *tempname, + uint64_t offset, uint64_t length, uint32_t anonymity, + enum GNUNET_FS_DownloadOptions options, void *cctx, + struct GNUNET_FS_DownloadContext *parent) +{ + struct GNUNET_FS_DownloadContext *dc; + + GNUNET_assert (GNUNET_FS_uri_test_chk (uri) || GNUNET_FS_uri_test_loc (uri)); + + if ((offset + length < offset) || + (offset + length > GNUNET_FS_uri_chk_get_file_size (uri))) + { + GNUNET_break (0); + return NULL; + } + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Starting download `%s' of %llu bytes\n", + filename, (unsigned long long) length); + dc = GNUNET_malloc (sizeof (struct GNUNET_FS_DownloadContext)); + dc->h = h; + dc->parent = parent; + if (parent != NULL) + { + GNUNET_CONTAINER_DLL_insert (parent->child_head, parent->child_tail, dc); + } + dc->uri = GNUNET_FS_uri_dup (uri); + dc->meta = GNUNET_CONTAINER_meta_data_duplicate (meta); + dc->client_info = cctx; + dc->start_time = GNUNET_TIME_absolute_get (); + if (NULL != filename) + { + dc->filename = GNUNET_strdup (filename); + if (GNUNET_YES == GNUNET_DISK_file_test (filename)) + GNUNET_DISK_file_size (filename, &dc->old_file_size, GNUNET_YES); + } + if (GNUNET_FS_uri_test_loc (dc->uri)) + GNUNET_assert (GNUNET_OK == + GNUNET_FS_uri_loc_get_peer_identity (dc->uri, &dc->target)); + dc->offset = offset; + dc->length = length; + dc->anonymity = anonymity; + dc->options = options; + dc->active = + GNUNET_CONTAINER_multihashmap_create (1 + 2 * (length / DBLOCK_SIZE)); + dc->treedepth = + GNUNET_FS_compute_depth (GNUNET_FS_uri_chk_get_file_size (dc->uri)); + if ((filename == NULL) && (is_recursive_download (dc))) + { + if (tempname != NULL) + dc->temp_filename = GNUNET_strdup (tempname); + else + dc->temp_filename = GNUNET_DISK_mktemp ("gnunet-directory-download-tmp"); + } + + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Download tree has depth %u\n", + dc->treedepth); + if (parent == NULL) + { + dc->top = + GNUNET_FS_make_top (dc->h, &GNUNET_FS_download_signal_suspend_, dc); + } + dc->task = GNUNET_SCHEDULER_add_now (&GNUNET_FS_download_start_task_, dc); + return dc; +} + + +/** + * Download parts of a file based on a search result. The download + * will be associated with the search result (and the association + * will be preserved when serializing/deserializing the state). + * If the search is stopped, the download will not be aborted but + * be 'promoted' to a stand-alone download. + * + * As with the other download function, this will store + * the blocks at the respective offset in the given file. Also, the + * download is still using the blocking of the underlying FS + * encoding. As a result, the download may *write* outside of the + * given boundaries (if offset and length do not match the 32k FS + * block boundaries). <p> + * + * The given range can be used to focus a download towards a + * particular portion of the file (optimization), not to strictly + * limit the download to exactly those bytes. + * + * @param h handle to the file sharing subsystem + * @param sr the search result to use for the download (determines uri and + * meta data and associations) + * @param filename where to store the file, maybe NULL (then no file is + * created on disk and data must be grabbed from the callbacks) + * @param tempname where to store temporary file data, not used if filename is non-NULL; + * can be NULL (in which case we will pick a name if needed); the temporary file + * may already exist, in which case we will try to use the data that is there and + * if it is not what is desired, will overwrite it + * @param offset at what offset should we start the download (typically 0) + * @param length how many bytes should be downloaded starting at offset + * @param anonymity anonymity level to use for the download + * @param options various download options + * @param cctx initial value for the client context for this download + * @return context that can be used to control this download + */ +struct GNUNET_FS_DownloadContext * +GNUNET_FS_download_start_from_search (struct GNUNET_FS_Handle *h, + struct GNUNET_FS_SearchResult *sr, + const char *filename, + const char *tempname, uint64_t offset, + uint64_t length, uint32_t anonymity, + enum GNUNET_FS_DownloadOptions options, + void *cctx) +{ + struct GNUNET_FS_DownloadContext *dc; + + if ((sr == NULL) || (sr->download != NULL)) + { + GNUNET_break (0); + return NULL; + } + GNUNET_assert (GNUNET_FS_uri_test_chk (sr->uri) || + GNUNET_FS_uri_test_loc (sr->uri)); + if ((offset + length < offset) || + (offset + length > sr->uri->data.chk.file_length)) + { + GNUNET_break (0); + return NULL; + } + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Starting download `%s' of %llu bytes\n", + filename, (unsigned long long) length); + dc = GNUNET_malloc (sizeof (struct GNUNET_FS_DownloadContext)); + dc->h = h; + dc->search = sr; + sr->download = dc; + if (sr->probe_ctx != NULL) + { + GNUNET_FS_download_stop (sr->probe_ctx, GNUNET_YES); + sr->probe_ctx = NULL; + } + dc->uri = GNUNET_FS_uri_dup (sr->uri); + dc->meta = GNUNET_CONTAINER_meta_data_duplicate (sr->meta); + dc->client_info = cctx; + dc->start_time = GNUNET_TIME_absolute_get (); + if (NULL != filename) + { + dc->filename = GNUNET_strdup (filename); + if (GNUNET_YES == GNUNET_DISK_file_test (filename)) + GNUNET_DISK_file_size (filename, &dc->old_file_size, GNUNET_YES); + } + if (GNUNET_FS_uri_test_loc (dc->uri)) + GNUNET_assert (GNUNET_OK == + GNUNET_FS_uri_loc_get_peer_identity (dc->uri, &dc->target)); + dc->offset = offset; + dc->length = length; + dc->anonymity = anonymity; + dc->options = options; + dc->active = + GNUNET_CONTAINER_multihashmap_create (1 + 2 * (length / DBLOCK_SIZE)); + dc->treedepth = + GNUNET_FS_compute_depth (GNUNET_ntohll (dc->uri->data.chk.file_length)); + if ((filename == NULL) && (is_recursive_download (dc))) + { + if (tempname != NULL) + dc->temp_filename = GNUNET_strdup (tempname); + else + dc->temp_filename = GNUNET_DISK_mktemp ("gnunet-directory-download-tmp"); + } + + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, "Download tree has depth %u\n", + dc->treedepth); + dc->task = GNUNET_SCHEDULER_add_now (&GNUNET_FS_download_start_task_, dc); + return dc; +} + + +/** + * Start the downloading process (by entering the queue). + * + * @param dc our download context + */ +void +GNUNET_FS_download_start_downloading_ (struct GNUNET_FS_DownloadContext *dc) +{ + if (dc->completed == dc->length) + return; + GNUNET_assert (dc->job_queue == NULL); + dc->job_queue = + GNUNET_FS_queue_ (dc->h, &activate_fs_download, &deactivate_fs_download, + dc, (dc->length + DBLOCK_SIZE - 1) / DBLOCK_SIZE); +} + + +/** + * Stop a download (aborts if download is incomplete). + * + * @param dc handle for the download + * @param do_delete delete files of incomplete downloads + */ +void +GNUNET_FS_download_stop (struct GNUNET_FS_DownloadContext *dc, int do_delete) +{ + struct GNUNET_FS_ProgressInfo pi; + int have_children; + + if (dc->top != NULL) + GNUNET_FS_end_top (dc->h, dc->top); + + + if (dc->task != GNUNET_SCHEDULER_NO_TASK) + { + GNUNET_SCHEDULER_cancel (dc->task); + dc->task = GNUNET_SCHEDULER_NO_TASK; + } + if (dc->search != NULL) + { + dc->search->download = NULL; + GNUNET_FS_search_result_sync_ (dc->search); + dc->search = NULL; + } + if (dc->job_queue != NULL) + { + GNUNET_FS_dequeue_ (dc->job_queue); + dc->job_queue = NULL; + } + if (dc->te != NULL) + { + GNUNET_FS_tree_encoder_finish (dc->te, NULL, NULL); + dc->te = NULL; + } + have_children = (NULL != dc->child_head) ? GNUNET_YES : GNUNET_NO; + while (NULL != dc->child_head) + GNUNET_FS_download_stop (dc->child_head, do_delete); + if (dc->parent != NULL) + GNUNET_CONTAINER_DLL_remove (dc->parent->child_head, dc->parent->child_tail, + dc); + if (dc->serialization != NULL) + GNUNET_FS_remove_sync_file_ (dc->h, + ((dc->parent != NULL) || + (dc->search != + NULL)) ? GNUNET_FS_SYNC_PATH_CHILD_DOWNLOAD : + GNUNET_FS_SYNC_PATH_MASTER_DOWNLOAD, + dc->serialization); + if ((GNUNET_YES == have_children) && (dc->parent == NULL)) + GNUNET_FS_remove_sync_dir_ (dc->h, + (dc->search != + NULL) ? GNUNET_FS_SYNC_PATH_CHILD_DOWNLOAD : + GNUNET_FS_SYNC_PATH_MASTER_DOWNLOAD, + dc->serialization); + pi.status = GNUNET_FS_STATUS_DOWNLOAD_STOPPED; + GNUNET_FS_download_make_status_ (&pi, dc); + GNUNET_FS_free_download_request_ (dc->top_request); + dc->top_request = NULL; + if (dc->active != NULL) + { + GNUNET_CONTAINER_multihashmap_destroy (dc->active); + dc->active = NULL; + } + if (dc->filename != NULL) + { + if ((dc->completed != dc->length) && (GNUNET_YES == do_delete)) + { + if (0 != UNLINK (dc->filename)) + GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_WARNING, "unlink", + dc->filename); + } + GNUNET_free (dc->filename); + } + GNUNET_CONTAINER_meta_data_destroy (dc->meta); + GNUNET_FS_uri_destroy (dc->uri); + if (NULL != dc->temp_filename) + { + if (0 != UNLINK (dc->temp_filename)) + GNUNET_log_strerror_file (GNUNET_ERROR_TYPE_ERROR, "unlink", + dc->temp_filename); + GNUNET_free (dc->temp_filename); + } + GNUNET_free_non_null (dc->serialization); + GNUNET_free (dc); +} + +/* end of fs_download.c */ |