net: add CVectorWriter and CNetMsgMaker

CVectorWriter is useful for overwriting or appending an existing byte vector.

CNetMsgMaker is a shortcut for creating messages on-the-fly which are suitable
for pushing to CConnman.

1 files changed, 58 insertions, 0 deletions

diff --git a/src/test/streams_tests.cpp b/src/test/streams_tests.cpp
index 34f501e867..8b715ce93e 100644
--- a/src/test/streams_tests.cpp
+++ b/src/test/streams_tests.cpp
@@ -15,6 +15,64 @@ using namespace boost::assign; // bring 'operator+=()' into scope
 
 BOOST_FIXTURE_TEST_SUITE(streams_tests, BasicTestingSetup)
 
+BOOST_AUTO_TEST_CASE(streams_vector_writer)
+{
+    unsigned char a(1);
+    unsigned char b(2);
+    unsigned char bytes[] = { 3, 4, 5, 6 };
+    std::vector<unsigned char> vch;
+
+    // Each test runs twice. Serializing a second time at the same starting
+    // point should yield the same results, even if the first test grew the
+    // vector.
+
+    CVectorWriter(SER_NETWORK, INIT_PROTO_VERSION, vch, 0, a, b);
+    BOOST_CHECK((vch == std::vector<unsigned char>{{1, 2}}));
+    CVectorWriter(SER_NETWORK, INIT_PROTO_VERSION, vch, 0, a, b);
+    BOOST_CHECK((vch == std::vector<unsigned char>{{1, 2}}));
+    vch.clear();
+
+    CVectorWriter(SER_NETWORK, INIT_PROTO_VERSION, vch, 2, a, b);
+    BOOST_CHECK((vch == std::vector<unsigned char>{{0, 0, 1, 2}}));
+    CVectorWriter(SER_NETWORK, INIT_PROTO_VERSION, vch, 2, a, b);
+    BOOST_CHECK((vch == std::vector<unsigned char>{{0, 0, 1, 2}}));
+    vch.clear();
+
+    vch.resize(5, 0);
+    CVectorWriter(SER_NETWORK, INIT_PROTO_VERSION, vch, 2, a, b);
+    BOOST_CHECK((vch == std::vector<unsigned char>{{0, 0, 1, 2, 0}}));
+    CVectorWriter(SER_NETWORK, INIT_PROTO_VERSION, vch, 2, a, b);
+    BOOST_CHECK((vch == std::vector<unsigned char>{{0, 0, 1, 2, 0}}));
+    vch.clear();
+
+    vch.resize(4, 0);
+    CVectorWriter(SER_NETWORK, INIT_PROTO_VERSION, vch, 3, a, b);
+    BOOST_CHECK((vch == std::vector<unsigned char>{{0, 0, 0, 1, 2}}));
+    CVectorWriter(SER_NETWORK, INIT_PROTO_VERSION, vch, 3, a, b);
+    BOOST_CHECK((vch == std::vector<unsigned char>{{0, 0, 0, 1, 2}}));
+    vch.clear();
+
+    vch.resize(4, 0);
+    CVectorWriter(SER_NETWORK, INIT_PROTO_VERSION, vch, 4, a, b);
+    BOOST_CHECK((vch == std::vector<unsigned char>{{0, 0, 0, 0, 1, 2}}));
+    CVectorWriter(SER_NETWORK, INIT_PROTO_VERSION, vch, 4, a, b);
+    BOOST_CHECK((vch == std::vector<unsigned char>{{0, 0, 0, 0, 1, 2}}));
+    vch.clear();
+
+    CVectorWriter(SER_NETWORK, INIT_PROTO_VERSION, vch, 0, FLATDATA(bytes));
+    BOOST_CHECK((vch == std::vector<unsigned char>{{3, 4, 5, 6}}));
+    CVectorWriter(SER_NETWORK, INIT_PROTO_VERSION, vch, 0, FLATDATA(bytes));
+    BOOST_CHECK((vch == std::vector<unsigned char>{{3, 4, 5, 6}}));
+    vch.clear();
+
+    vch.resize(4, 8);
+    CVectorWriter(SER_NETWORK, INIT_PROTO_VERSION, vch, 2, a, FLATDATA(bytes), b);
+    BOOST_CHECK((vch == std::vector<unsigned char>{{8, 8, 1, 3, 4, 5, 6, 2}}));
+    CVectorWriter(SER_NETWORK, INIT_PROTO_VERSION, vch, 2, a, FLATDATA(bytes), b);
+    BOOST_CHECK((vch == std::vector<unsigned char>{{8, 8, 1, 3, 4, 5, 6, 2}}));
+    vch.clear();
+}
+
 BOOST_AUTO_TEST_CASE(streams_serializedata_xor)
 {
     std::vector<char> in;