some cast cleanup, const modifier and lint refactor

src/udp_socket.cpp

@@ -167,8 +167,8 @@ int udp_socket::read(span<packet> pkts, error_code& ec)
 
 	while (ret < num)
 	{
-		int const len = int(m_socket.receive_from(boost::asio::buffer(*m_buf)
-			, p.from, 0, ec));
+		std::size_t const len = m_socket.receive_from(boost::asio::buffer(*m_buf)
+			, p.from, 0, ec);
 
 		if (ec == error::would_block
 			|| ec == error::try_again
@@ -197,7 +197,7 @@ int udp_socket::read(span<packet> pkts, error_code& ec)
 		}
 		else
 		{
-			p.data = {m_buf->data(), aux::numeric_cast<std::size_t>(len)};
+			p.data = {m_buf->data(), len};
 
 			// support packets coming from the SOCKS5 proxy
 			if (m_socks5_connection && m_socks5_connection->active())

src/udp_tracker_connection.cpp

@@ -520,7 +520,7 @@ namespace libtorrent {
 		aux::write_uint32(0x27101980, view); // connection_id
 		aux::write_int32(action_t::connect, view); // action (connect)
 		aux::write_int32(m_transaction_id, view); // transaction_id
-		TORRENT_ASSERT(view.size() == 0);
+		TORRENT_ASSERT(view.empty());
 
 		error_code ec;
 		if (!m_hostname.empty())
@@ -627,7 +627,7 @@ namespace libtorrent {
 #endif
 			6;
 
-		int const num_peers = static_cast<int>(buf.size() / ip_stride);
+		std::size_t const num_peers = buf.size() / ip_stride;
 		if (buf.size() % ip_stride != 0)
 		{
 			fail(error_code(errors::invalid_tracker_response_length));
@@ -651,8 +651,8 @@ namespace libtorrent {
 #if TORRENT_USE_IPV6
 		if (is_v6(m_target))
 		{
-			resp.peers6.reserve(std::size_t(num_peers));
-			for (int i = 0; i < num_peers; ++i)
+			resp.peers6.reserve(num_peers);
+			for (std::size_t i = 0; i < num_peers; ++i)
 			{
 				ipv6_peer_entry e{};
 				std::memcpy(e.ip.data(), buf.data(), 16);
@@ -664,8 +664,8 @@ namespace libtorrent {
 		else
 #endif
 		{
-			resp.peers4.reserve(std::size_t(num_peers));
-			for (int i = 0; i < num_peers; ++i)
+			resp.peers4.reserve(num_peers);
+			for (std::size_t i = 0; i < num_peers; ++i)
 			{
 				ipv4_peer_entry e{};
 				std::memcpy(e.ip.data(), buf.data(), 4);

src/ut_metadata.cpp

@@ -149,6 +149,9 @@ namespace libtorrent {namespace {
 			m_requested_metadata.resize(div_round_up(size, 16 * 1024));
 		}
 
+		// explicitly disallow assignment, to silence msvc warning
+		ut_metadata_plugin& operator=(ut_metadata_plugin const&) = delete;
+
 	private:
 		torrent& m_torrent;
 
@@ -174,9 +177,6 @@ namespace libtorrent {namespace {
 		// block has been requested and who we ended up getting it from
 		// std::numeric_limits<int>::max() means we have the piece
 		aux::vector<metadata_piece> m_requested_metadata;
-
-		// explicitly disallow assignment, to silence msvc warning
-		ut_metadata_plugin& operator=(ut_metadata_plugin const&);
 	};
 
 
@@ -253,17 +253,17 @@ namespace libtorrent {namespace {
 
 			if (type == 1)
 			{
-				TORRENT_ASSERT(piece >= 0 && piece < int(m_tp.get_metadata_size() + 16 * 1024 - 1)/(16*1024));
+				TORRENT_ASSERT(piece >= 0 && piece < (m_tp.get_metadata_size() + 16 * 1024 - 1) / (16 * 1024));
 				TORRENT_ASSERT(m_pc.associated_torrent().lock()->valid_metadata());
 				TORRENT_ASSERT(m_torrent.valid_metadata());
 
-				int offset = piece * 16 * 1024;
+				int const offset = piece * 16 * 1024;
 				metadata = m_tp.metadata().data() + offset;
 				metadata_piece_size = std::min(
 					m_tp.get_metadata_size() - offset, 16 * 1024);
 				TORRENT_ASSERT(metadata_piece_size > 0);
 				TORRENT_ASSERT(offset >= 0);
-				TORRENT_ASSERT(offset + metadata_piece_size <= int(m_tp.get_metadata_size()));
+				TORRENT_ASSERT(offset + metadata_piece_size <= m_tp.get_metadata_size());
 			}
 
 			// TODO: 3 use the aux::write_* functions and the span here instead, it
@@ -291,8 +291,8 @@ namespace libtorrent {namespace {
 			m_pc.stats_counters().inc_stats_counter(counters::num_outgoing_metadata);
 		}
 
-		bool on_extended(int length
-			, int extended_msg, span<char const> body) override
+		bool on_extended(int const length
+			, int const extended_msg, span<char const> body) override
 		{
 			if (extended_msg != 2) return false;
 			if (m_message_index == 0) return false;
@@ -455,6 +455,9 @@ namespace libtorrent {namespace {
 			m_request_limit = now + seconds(20 + random(50));
 		}
 
+		// explicitly disallow assignment, to silence msvc warning
+		ut_metadata_peer_plugin& operator=(ut_metadata_peer_plugin const&) = delete;
+
 	private:
 
 		// this is the message index the remote peer uses
@@ -474,9 +477,6 @@ namespace libtorrent {namespace {
 		torrent& m_torrent;
 		bt_peer_connection& m_pc;
 		ut_metadata_plugin& m_tp;
-
-		// explicitly disallow assignment, to silence msvc warning
-		ut_metadata_peer_plugin& operator=(ut_metadata_peer_plugin const&);
 	};
 
 	std::shared_ptr<peer_plugin> ut_metadata_plugin::new_connection(
@@ -507,7 +507,7 @@ namespace libtorrent {namespace {
 		int const piece = int(i - m_requested_metadata.begin());
 
 		// don't request the same block more than once every 3 seconds
-		time_point now = aux::time_now();
+		time_point const now = aux::time_now();
 		if (m_requested_metadata[piece].last_request != min_time()
 			&& total_seconds(now - m_requested_metadata[piece].last_request) < 3)
 			return -1;
@@ -595,7 +595,7 @@ namespace libtorrent {namespace {
 		{
 			if (!m_torrent.valid_metadata())
 			{
-				time_point now = aux::time_now();
+				time_point const now = aux::time_now();
 				// any peer that we downloaded metadata from gets a random time
 				// penalty, from 5 to 30 seconds or so. During this time we don't
 				// make any metadata requests from those peers (to mix it up a bit
@@ -622,7 +622,8 @@ namespace libtorrent {namespace {
 		metadata();
 
 		// clear the storage for the bitfield
-		std::vector<metadata_piece>().swap(m_requested_metadata);
+		m_requested_metadata.clear();
+		m_requested_metadata.shrink_to_fit();
 
 		return true;
 	}