improve interoperability between bdecode_node and entry (for encoding). Make it possible to construct an entry from a bdecode_node. move comparison operators out of entry to support implicit conversions from bdecode_node

include/libtorrent/bdecode.hpp

@@ -438,6 +438,8 @@ TORRENT_EXPORT int bdecode(char const* start, char const* end, bdecode_node& ret
 TORRENT_EXPORT bdecode_node bdecode(span<char const> buffer
 	, error_code& ec, int* error_pos = nullptr, int depth_limit = 100
 	, int token_limit = 2000000);
+TORRENT_EXPORT bdecode_node bdecode(span<char const> buffer
+	, int depth_limit = 100, int token_limit = 2000000);
 
 }
 

include/libtorrent/bencode.hpp

@@ -434,7 +434,6 @@ namespace detail {
 		if (err) return entry();
 		return e;
 	}
-	entry bdecode(span<char const> buffer);
 }
 
 #endif // TORRENT_BENCODE_HPP_INCLUDED

include/libtorrent/entry.hpp

@@ -178,16 +178,15 @@ namespace aux {
 		entry(entry const& e);
 		entry(entry&& e) noexcept;
 
+		// construct from bdecode_node parsed form (see bdecode())
+		entry(bdecode_node const& n); // NOLINT
+
 		// hidden
 		entry();
 
 		// hidden
 		~entry();
 
-		// hidden
-		bool operator==(entry const& e) const;
-		bool operator!=(entry const& e) const { return !(*this == e); }
-
 		// copies the structure of the right hand side into this
 		// entry.
 #if TORRENT_ABI_VERSION == 1
@@ -340,9 +339,13 @@ namespace aux {
 		mutable std::uint8_t m_type_queried:1;
 	};
 
+	TORRENT_EXPORT bool operator==(entry const& lhs, entry const& rhs);
+	inline bool operator!=(entry const& lhs, entry const& rhs) { return !(lhs == rhs); }
+
 namespace detail {
 
-	TORRENT_EXTRA_EXPORT string_view integer_to_str(span<char> buf
+	// internal
+	TORRENT_EXPORT string_view integer_to_str(span<char> buf
 		, entry::integer_type val);
 }
 

src/bdecode.cpp

@@ -33,6 +33,7 @@ POSSIBILITY OF SUCH DAMAGE.
 #include "libtorrent/bdecode.hpp"
 #include "libtorrent/aux_/alloca.hpp"
 #include "libtorrent/aux_/numeric_cast.hpp"
+#include "libtorrent/error_code.hpp"
 #include <limits>
 #include <cstring> // for memset
 #include <cstdio> // for snprintf
@@ -735,6 +736,14 @@ namespace {
 		return ec ? -1 : 0;
 	}
 
+	bdecode_node bdecode(span<char const> buffer, int depth_limit, int token_limit)
+	{
+		error_code ec;
+		bdecode_node ret = bdecode(buffer, ec, nullptr, depth_limit, token_limit);
+		if (ec) throw system_error(ec);
+		return ret;
+	}
+
 	bdecode_node bdecode(span<char const> buffer
 		, error_code& ec, int* error_pos, int depth_limit, int token_limit)
 	{

src/entry.cpp

@@ -68,17 +68,6 @@ namespace detail {
 	}
 } // detail
 
-	entry bdecode(span<char const> buffer)
-	{
-		entry e;
-		bool err = false;
-		auto it = buffer.begin();
-		detail::bdecode_recursive(it, buffer.end(), e, err, 0);
-		TORRENT_ASSERT(e.m_type_queried == false);
-		if (err) return entry();
-		return e;
-	}
-
 namespace {
 
 	inline void TORRENT_NO_RETURN throw_error()
@@ -311,6 +300,12 @@ namespace {
 		this->operator=(std::move(e));
 	}
 
+	entry::entry(bdecode_node const& n)
+		: m_type(undefined_t)
+	{
+		this->operator=(n);
+	}
+
 	entry::entry(dictionary_type v)
 		: m_type(undefined_t)
 	{
@@ -494,26 +489,26 @@ namespace {
 		return *this;
 	}
 
-	bool entry::operator==(entry const& e) const
+	bool operator==(entry const& lhs, entry const& rhs)
 	{
-		if (type() != e.type()) return false;
+		if (lhs.type() != rhs.type()) return false;
 
-		switch (m_type)
+		switch (lhs.type())
 		{
-		case int_t:
+		case entry::int_t:
-			return integer() == e.integer();
+			return lhs.integer() == rhs.integer();
-		case string_t:
+		case entry::string_t:
-			return string() == e.string();
+			return lhs.string() == rhs.string();
-		case list_t:
+		case entry::list_t:
-			return list() == e.list();
+			return lhs.list() == rhs.list();
-		case dictionary_t:
+		case entry::dictionary_t:
-			return dict() == e.dict();
+			return lhs.dict() == rhs.dict();
-		case preformatted_t:
+		case entry::preformatted_t:
-			return preformatted() == e.preformatted();
+			return lhs.preformatted() == rhs.preformatted();
-		default:
+		case entry::undefined_t:
-			TORRENT_ASSERT(m_type == undefined_t);
 			return true;
 		}
+		return false;
 	}
 
 	void entry::construct(data_type t)

src/kademlia/dht_storage.cpp

@@ -48,6 +48,7 @@ POSSIBILITY OF SUCH DAMAGE.
 #include <libtorrent/aux_/vector.hpp>
 #include <libtorrent/aux_/numeric_cast.hpp>
 #include <libtorrent/broadcast_socket.hpp> // for ip_v4
+#include <libtorrent/bdecode.hpp>
 
 namespace libtorrent { namespace dht {
 namespace {
@@ -355,8 +356,8 @@ namespace {
 			auto const i = m_immutable_table.find(target);
 			if (i == m_immutable_table.end()) return false;
 
-			item["v"] = bdecode(i->second.value.get()
+			error_code ec;
-				, i->second.value.get() + i->second.size);
+			item["v"] = bdecode({i->second.value.get(), i->second.size}, ec);
 			return true;
 		}
 
@@ -412,7 +413,8 @@ namespace {
 			item["seq"] = f.seq.value;
 			if (force_fill || (sequence_number(0) <= seq && seq < f.seq))
 			{
-				item["v"] = bdecode(f.value.get(), f.value.get() + f.size);
+				error_code ec;
+				item["v"] = bdecode({f.value.get(), f.size}, ec);
 				item["sig"] = f.sig.bytes;
 				item["k"] = f.key.bytes;
 			}

test/test_bencoding.cpp

@@ -31,6 +31,7 @@ POSSIBILITY OF SUCH DAMAGE.
 */
 
 #include "libtorrent/bencode.hpp"
+#include "libtorrent/bdecode.hpp"
 
 #include <iostream>
 #include <cstring>
@@ -56,39 +57,34 @@ std::string encode(entry const& e)
 	return ret;
 }
 
-entry decode(std::string const& str)
-{
-	return bdecode(str.begin(), str.end());
-}
-
 } // anonymous namespace
 
 TORRENT_TEST(strings)
 {
 	entry e("spam");
 	TEST_CHECK(encode(e) == "4:spam");
-	TEST_CHECK(decode(encode(e)) == e);
+	TEST_CHECK(bdecode(encode(e)) == e);
 }
 
 TORRENT_TEST(integers)
 {
 	entry e(3);
 	TEST_CHECK(encode(e) == "i3e");
-	TEST_CHECK(decode(encode(e)) == e);
+	TEST_CHECK(bdecode(encode(e)) == e);
 }
 
 TORRENT_TEST(integers2)
 {
 	entry e(-3);
 	TEST_CHECK(encode(e) == "i-3e");
-	TEST_CHECK(decode(encode(e)) == e);
+	TEST_CHECK(bdecode(encode(e)) == e);
 }
 
 TORRENT_TEST(integers3)
 {
 	entry e(int(0));
 	TEST_CHECK(encode(e) == "i0e");
-	TEST_CHECK(decode(encode(e)) == e);
+	TEST_CHECK(bdecode(encode(e)) == e);
 }
 
 TORRENT_TEST(lists)
@@ -98,7 +94,7 @@ TORRENT_TEST(lists)
 	l.push_back(entry("eggs"));
 	entry e(l);
 	TEST_CHECK(encode(e) == "l4:spam4:eggse");
-	TEST_CHECK(decode(encode(e)) == e);
+	TEST_CHECK(bdecode(encode(e)) == e);
 }
 
 TORRENT_TEST(dictionaries)
@@ -107,7 +103,7 @@ TORRENT_TEST(dictionaries)
 	e["spam"] = entry("eggs");
 	e["cow"] = entry("moo");
 	TEST_CHECK(encode(e) == "d3:cow3:moo4:spam4:eggse");
-	TEST_CHECK(decode(encode(e)) == e);
+	TEST_CHECK(bdecode(encode(e)) == e);
 }
 
 TORRENT_TEST(preformatted)
@@ -620,7 +616,8 @@ TORRENT_TEST(lazy_entry)
 
 	{
 		unsigned char buf[] = { 0x44, 0x91, 0x3a };
-		entry ent = bdecode(reinterpret_cast<char*>(buf), reinterpret_cast<char*>(buf) + sizeof(buf));
+		error_code ec;
+		entry ent = bdecode({reinterpret_cast<char*>(buf), int(sizeof(buf))}, ec);
 		TEST_CHECK(ent == entry());
 	}
 

test/test_fast_extension.cpp

@@ -154,7 +154,7 @@ void print_message(char const* buffer, int len)
 		else if (msg == 20 && len > 4 && buffer[1] == 0 )
 		{
 			std::snprintf(extra, sizeof(extra), "%s"
-				, bdecode(buffer + 2, buffer + len).to_string().c_str());
+				, print_entry(bdecode({buffer + 2, len - 2})).c_str());
 		}
 	}
 
@@ -356,7 +356,7 @@ entry read_extension_handshake(tcp::socket& s, char* recv_buffer, int size)
 		int extmsg = recv_buffer[1];
 		if (extmsg != 0) continue;
 
-		return bdecode(recv_buffer + 2, recv_buffer + len);
+		return bdecode({recv_buffer + 2, len - 2});
 	}
 }
 
@@ -409,7 +409,7 @@ entry read_ut_metadata_msg(tcp::socket& s, char* recv_buffer, int size)
 		int extmsg = recv_buffer[1];
 		if (extmsg != 1) continue;
 
-		return bdecode(recv_buffer + 2, recv_buffer + len);
+		return bdecode({recv_buffer + 2, len - 2});
 	}
 }
 #endif // TORRENT_DISABLE_EXTENSIONS
@@ -831,7 +831,7 @@ TORRENT_TEST(dont_have)
 	{
 		print_session_log(*ses);
 
-		int len = read_message(s, recv_buffer, sizeof(recv_buffer));
+		int const len = read_message(s, recv_buffer, sizeof(recv_buffer));
 		if (len == -1) break;
 		print_message(recv_buffer, len);
 		if (len == 0) continue;
@@ -840,15 +840,15 @@ TORRENT_TEST(dont_have)
 		int ext_msg = recv_buffer[1];
 		if (ext_msg != 0) continue;
 
-		bdecode_node e;
 		int pos = 0;
-		int ret = bdecode(recv_buffer + 2, recv_buffer + len, e, ec, &pos);
+		ec.clear();
-		if (ret != 0)
+		bdecode_node e = bdecode({recv_buffer + 2, len - 2}, ec, &pos);
+		if (ec)
 		{
 			log("failed to parse extension handshake: %s at pos %d"
 				, ec.message().c_str(), pos);
 		}
-		TEST_EQUAL(ret, 0);
+		TEST_CHECK(!ec);
 
 		log("extension handshake: %s", print_entry(e).c_str());
 		bdecode_node m = e.dict_find_dict("m");

test/test_read_resume.cpp

@@ -201,7 +201,7 @@ TORRENT_TEST(read_resume_torrent)
 	rd["file-format"] = "libtorrent resume file";
 	rd["file-version"] = 1;
 	rd["info-hash"] = ti->info_hash().to_string();
-	rd["info"] = bdecode(ti->metadata().get(), ti->metadata().get() + ti->metadata_size());
+	rd["info"] = bdecode({ti->metadata().get(), ti->metadata_size()});
 
 	std::vector<char> resume_data;
 	bencode(std::back_inserter(resume_data), rd);

test/test_resume.cpp

@@ -890,7 +890,7 @@ TORRENT_TEST(backwards_compatible_resume_info_dict)
 	rd["name"] = ti->name();
 	rd["info-hash"] = ti->info_hash();
 	auto metainfo = ti->metadata();
-	rd["info"] = bdecode(metainfo.get(), metainfo.get() + ti->metadata_size());
+	rd["info"] = bdecode({metainfo.get(), ti->metadata_size()});
 	std::vector<char> resume_data;
 	bencode(back_inserter(resume_data), rd);
 
@@ -917,7 +917,7 @@ TORRENT_TEST(resume_info_dict)
 	rd["name"] = ti->name();
 	rd["info-hash"] = ti->info_hash();
 	auto metainfo = ti->metadata();
-	rd["info"] = bdecode(metainfo.get(), metainfo.get() + ti->metadata_size());
+	rd["info"] = bdecode({metainfo.get(), ti->metadata_size()});
 	std::vector<char> resume_data;
 	bencode(back_inserter(resume_data), rd);