Enable torrent manager to check whether we already have a requested torrent file segment, manifest file segment, data packet before downloading
Refs: #3505
Change-Id: I97472459a774b1a858462f82a5b7d9606bd0843a
diff --git a/src/torrent-manager.cpp b/src/torrent-manager.cpp
index c06db40..4a0eaff 100644
--- a/src/torrent-manager.cpp
+++ b/src/torrent-manager.cpp
@@ -436,18 +436,44 @@
void
TorrentManager::downloadTorrentFile(const std::string& path,
- DataReceivedCallback onSuccess,
+ TorrentFileReceivedCallback onSuccess,
FailedCallback onFailed)
{
+ shared_ptr<Name> searchRes = this->findTorrentFileSegmentToDownload();
auto manifestNames = make_shared<std::vector<Name>>();
- this->downloadTorrentFileSegment(m_torrentFileName, path, manifestNames,
+ if (searchRes == nullptr) {
+ this->findFileManifestsToDownload(*manifestNames);
+ if (manifestNames->empty()) {
+ auto packetNames = make_shared<std::vector<Name>>();
+ this->findAllMissingDataPackets(*packetNames);
+ onSuccess(*packetNames);
+ return;
+ }
+ else {
+ onSuccess(*manifestNames);
+ return;
+ }
+ }
+ this->downloadTorrentFileSegment(*searchRes, path, manifestNames,
true, onSuccess, onFailed);
}
std::vector<Name>
TorrentManager::downloadTorrentFile(const std::string& path)
{
+ shared_ptr<Name> searchRes = this->findTorrentFileSegmentToDownload();
auto manifestNames = make_shared<std::vector<Name>>();
+ if (searchRes == nullptr) {
+ this->findFileManifestsToDownload(*manifestNames);
+ if (manifestNames->empty()) {
+ auto packetNames = make_shared<std::vector<Name>>();
+ this->findAllMissingDataPackets(*packetNames);
+ return *packetNames;
+ }
+ else {
+ return *manifestNames;
+ }
+ }
this->downloadTorrentFileSegment(m_torrentFileName, path, manifestNames,
false, {}, {});
return *manifestNames;
@@ -458,7 +484,7 @@
const std::string& path,
std::shared_ptr<std::vector<Name>> manifestNames,
bool async,
- DataReceivedCallback onSuccess,
+ TorrentFileReceivedCallback onSuccess,
FailedCallback onFailed)
{
shared_ptr<Interest> interest = createInterest(name);
@@ -469,6 +495,10 @@
m_stats_table_iter->incrementReceivedData();
m_retries = 0;
+ if (async) {
+ manifestNames->clear();
+ }
+
TorrentFile file(data.wireEncode());
// Write the torrent file segment to disk...
@@ -480,7 +510,7 @@
shared_ptr<Name> nextSegmentPtr = file.getTorrentFilePtr();
if (async) {
- onSuccess(file.getName());
+ onSuccess(*manifestNames);
}
if (nextSegmentPtr != nullptr) {
this->downloadTorrentFileSegment(*nextSegmentPtr, path, manifestNames,
@@ -517,8 +547,14 @@
TorrentManager::ManifestReceivedCallback onSuccess,
TorrentManager::FailedCallback onFailed)
{
+ shared_ptr<Name> searchRes = findManifestSegmentToDownload(manifestName);
auto packetNames = make_shared<std::vector<Name>>();
- this->downloadFileManifestSegment(manifestName, path, packetNames, onSuccess, onFailed);
+ if (searchRes == nullptr) {
+ this->findDataPacketsToDownload(manifestName, *packetNames);
+ onSuccess(*packetNames);
+ return;
+ }
+ this->downloadFileManifestSegment(*searchRes, path, packetNames, onSuccess, onFailed);
}
void
@@ -570,6 +606,11 @@
DataReceivedCallback onSuccess,
FailedCallback onFailed)
{
+ if (this->dataAlreadyDownloaded(packetName)) {
+ onSuccess(packetName);
+ return;
+ }
+
shared_ptr<Interest> interest = this->createInterest(packetName);
auto dataReceived = [onSuccess, onFailed, this]
@@ -624,5 +665,121 @@
return interest;
}
+shared_ptr<Name>
+TorrentManager::findTorrentFileSegmentToDownload()
+{
+ // if we have no segments
+ if (m_torrentSegments.empty()) {
+ return make_shared<Name>(m_torrentFileName);
+ }
+ // otherwise just return the next segment ptr of the last segment we have
+ return m_torrentSegments.back().getTorrentFilePtr();
+}
+
+shared_ptr<Name>
+TorrentManager::findManifestSegmentToDownload(const Name& manifestName)
+{
+ //sequentially find whether we have downloaded any segments of this manifest file
+ Name manifestPrefix = manifestName.getSubName(0, manifestName.size() - 2);
+ auto it = std::find_if(m_fileManifests.rbegin(), m_fileManifests.rend(),
+ [&manifestPrefix] (const FileManifest& f) {
+ return manifestPrefix.isPrefixOf(f.getName());
+ });
+
+ // if we do not have any segments of the file manifest
+ if (it == m_fileManifests.rend()) {
+ return make_shared<Name>(manifestName);
+ }
+
+ // if we already have the requested segment of the file manifest
+ if (it->submanifest_number() >= manifestName.get(manifestName.size() - 2).toSequenceNumber()) {
+ return it->submanifest_ptr();
+ }
+ // if we do not have the requested segment
+ else {
+ return make_shared<Name>(manifestName);
+ }
+}
+
+bool
+TorrentManager::dataAlreadyDownloaded(const Name& dataName)
+{
+
+ auto manifest_it = std::find_if(m_fileManifests.begin(), m_fileManifests.end(),
+ [&dataName](const FileManifest& m) {
+ return m.getName().isPrefixOf(dataName);
+ });
+
+ // if we do not have the file manifest, just return false
+ if (manifest_it == m_fileManifests.end()) {
+ return false;
+ }
+
+ // find the pair of (std::shared_ptr<fs::fstream>, std::vector<bool>)
+ // that corresponds to the specific submanifest
+ auto& fileState = m_fileStates[manifest_it->getFullName()];
+
+ auto dataNum = dataName.get(dataName.size() - 2).toSequenceNumber();
+
+ // find whether we have the requested packet from the bitmap
+ return fileState.second[dataNum];
+}
+
+void
+TorrentManager::findFileManifestsToDownload(std::vector<Name>& manifestNames)
+{
+ std::vector<Name> manifests;
+ // insert the first segment name of all the file manifests to the vector
+ for (auto i = m_torrentSegments.begin(); i != m_torrentSegments.end(); i++) {
+ manifests.insert(manifests.end(), i->getCatalog().begin(), i->getCatalog().end());
+ }
+ // for each file
+ for (const auto& manifestName : manifests) {
+ // find the first (if any) segment we are missing
+ shared_ptr<Name> manifestSegmentName = findManifestSegmentToDownload(manifestName);
+ if (nullptr != manifestSegmentName) {
+ manifestNames.push_back(*manifestSegmentName);
+ }
+ }
+}
+
+void
+TorrentManager::findDataPacketsToDownload(const Name& manifestName, std::vector<Name>& packetNames)
+{
+ auto manifest_it = std::find_if(m_fileManifests.begin(), m_fileManifests.end(),
+ [&manifestName](const FileManifest& m) {
+ return m.name().getSubName(0, m.name().size()
+ - 1).isPrefixOf(manifestName);
+ });
+
+ for (auto j = manifest_it; j != m_fileManifests.end(); j++) {
+ auto& fileState = m_fileStates[j->getFullName()];
+ for (size_t dataNum = 0; dataNum < j->catalog().size(); ++dataNum) {
+ if (!fileState.second[dataNum]) {
+ packetNames.push_back(j->catalog()[dataNum]);
+ }
+ }
+
+ // check that the next manifest in the vector refers to the next segment of the same file
+ if ((j + 1) != m_fileManifests.end() && (j+1)->file_name() != manifest_it->file_name()) {
+ break;
+ }
+ }
+}
+
+void
+TorrentManager::findAllMissingDataPackets(std::vector<Name>& packetNames)
+{
+ for (auto j = m_fileManifests.begin(); j != m_fileManifests.end(); j++) {
+ auto& fileState = m_fileStates[j->getFullName()];
+ for (auto i = j->catalog().begin(); i != j->catalog().end(); i++) {
+ auto dataNum = i->get(i->size() - 2).toSequenceNumber();
+ if (!fileState.second[dataNum]) {
+ packetNames.push_back(*i);
+ }
+ }
+ }
+}
+
} // end ntorrent
} // end ndn