fixing sign-conversion warnings, part 20 (#1745)

fixing sign-conversion warnings, part 20

include/libtorrent/aux_/session_impl.hpp

@@ -553,7 +553,7 @@ namespace libtorrent
 			void get_cache_info(torrent_handle h, cache_status* ret, int flags) const;
 
 			void set_peer_id(peer_id const& id);
-			void set_key(int key);
+			void set_key(std::uint32_t key);
 			std::uint16_t listen_port() const override;
 			std::uint16_t ssl_listen_port() const override;
 
@@ -875,7 +875,7 @@ namespace libtorrent
 			// the key is an id that is used to identify the
 			// client with the tracker only. It is randomized
 			// at startup
-			int m_key = 0;
+			std::uint32_t m_key = 0;
 
 			// posts a notification when the set of local IPs changes
 			ip_change_notifier m_ip_notifier;

include/libtorrent/io.hpp

@@ -38,6 +38,7 @@ POSSIBILITY OF SUCH DAMAGE.
 #include <algorithm> // for copy
 #include <cstring> // for memcpy
 #include <type_traits>
+#include <iterator>
 
 #include "assert.hpp"
 
@@ -80,11 +81,19 @@ namespace libtorrent
 				|| std::is_enum<In>::value>::type>
 		inline void write_impl(In data, OutIt& start)
 		{
+			// Note: the test for [OutItT==void] below is necessary because
+			// in C++11 std::back_insert_iterator::value_type is void.
+			// This could change in C++17 or above
+			using OutItT = typename std::iterator_traits<OutIt>::value_type;
+			using Byte = typename std::conditional<
+				std::is_same<OutItT, void>::value, char, OutItT>::type;
+			static_assert(sizeof(Byte) == 1, "wrong iterator or pointer type");
+
 			T val = static_cast<T>(data);
 			TORRENT_ASSERT(data == static_cast<In>(val));
 			for (int i = int(sizeof(T)) - 1; i >= 0; --i)
 			{
-				*start = static_cast<unsigned char>((val >> (i * 8)) & 0xff);
+				*start = static_cast<Byte>((val >> (i * 8)) & 0xff);
 				++start;
 			}
 		}

include/libtorrent/packet_pool.hpp

@@ -109,7 +109,7 @@ namespace libtorrent
 
 	inline packet_ptr create_packet(int const size)
 	{
-		packet* p = static_cast<packet*>(std::malloc(sizeof(packet) + size));
+		packet* p = static_cast<packet*>(std::malloc(sizeof(packet) + aux::numeric_cast<std::uint16_t>(size)));
 		if (p == nullptr) aux::throw_ex<std::bad_alloc>();
 		new (p) packet();
 		p->allocated = aux::numeric_cast<std::uint16_t>(size);

include/libtorrent/session_handle.hpp

@@ -581,7 +581,7 @@ namespace libtorrent
 		// sets the key sent to trackers. If it's not set, it is initialized
 		// by libtorrent. The key may be used by the tracker to identify the
 		// peer potentially across you changing your IP.
-		void set_key(int key);
+		void set_key(std::uint32_t key);
 
 		// built-in peer classes
 		static constexpr peer_class_t global_peer_class_id{0};

src/session_handle.cpp

@@ -750,7 +750,7 @@ namespace libtorrent
 		return sync_call_ret<peer_id>(&session_impl::get_peer_id);
 	}
 
-	void session_handle::set_key(int key)
+	void session_handle::set_key(std::uint32_t key)
 	{
 		async_call(&session_impl::set_key, key);
 	}

src/session_impl.cpp

@@ -2913,7 +2913,7 @@ namespace aux {
 		m_peer_id = id;
 	}
 
-	void session_impl::set_key(int key)
+	void session_impl::set_key(std::uint32_t key)
 	{
 		m_key = key;
 	}

src/timestamp_history.cpp

@@ -32,6 +32,7 @@ POSSIBILITY OF SUCH DAMAGE.
 
 
 #include "libtorrent/timestamp_history.hpp"
+#include "libtorrent/aux_/numeric_cast.hpp"
 
 namespace libtorrent {
 
@@ -93,7 +94,7 @@ std::uint32_t timestamp_history::add_sample(std::uint32_t sample, bool step)
 void timestamp_history::adjust_base(int change)
 {
 	TORRENT_ASSERT(initialized());
-	m_base += change;
+	m_base += aux::numeric_cast<std::uint32_t>(change);
 	// make sure this adjustment sticks by updating all history slots
 	for (int i = 0; i < history_size; ++i)
 	{

src/utp_stream.cpp

@@ -1720,7 +1720,7 @@ bool utp_socket_impl::send_pkt(int const flags)
 	// congestion window and the advertised receive window from
 	// the other end.
 	if (m_bytes_in_flight + payload_size > std::min(int(m_cwnd >> 16)
-		, int(m_adv_wnd - m_bytes_in_flight)))
+		, int(m_adv_wnd) - m_bytes_in_flight))
 	{
 		// this means there's not enough room in the send window for
 		// another packet. We have to hold off sending this data.