net: add RAII socket and use it instead of bare SOCKET

Introduce a class to manage the lifetime of a socket - when the object
that contains the socket goes out of scope, the underlying socket will
be closed.

In addition, the new `Sock` class has a `Send()`, `Recv()` and `Wait()`
methods that can be overridden by unit tests to mock the socket
operations.

The `Wait()` method also hides the
`#ifdef USE_POLL poll() #else select() #endif` technique from higher
level code.

1 files changed, 6 insertions, 0 deletions

diff --git a/src/util/time.h b/src/util/time.h
index 2c0e3d83f6..03b75b5be5 100644
--- a/src/util/time.h
+++ b/src/util/time.h
@@ -27,6 +27,7 @@ void UninterruptibleSleep(const std::chrono::microseconds& n);
  * interface that doesn't support std::chrono (e.g. RPC, debug log, or the GUI)
  */
 inline int64_t count_seconds(std::chrono::seconds t) { return t.count(); }
+inline int64_t count_milliseconds(std::chrono::milliseconds t) { return t.count(); }
 inline int64_t count_microseconds(std::chrono::microseconds t) { return t.count(); }
 
 /**
@@ -64,4 +65,9 @@ int64_t ParseISO8601DateTime(const std::string& str);
  */
 struct timeval MillisToTimeval(int64_t nTimeout);
 
+/**
+ * Convert milliseconds to a struct timeval for e.g. select.
+ */
+struct timeval MillisToTimeval(std::chrono::milliseconds ms);
+
 #endif // BITCOIN_UTIL_TIME_H