net: move CloseSocket() from netbase to util/sock

Move `CloseSocket()` (and `NetworkErrorString()` which it uses) from
`netbase.{h,cpp}` to newly added `src/util/sock.{h,cpp}`.

This is necessary in order to use `CloseSocket()` from a newly
introduced Sock class (which will live in `src/util/sock.{h,cpp}`).
`sock.{h,cpp}` cannot depend on netbase because netbase will depend
on it.

1 files changed, 18 insertions, 0 deletions

diff --git a/src/util/sock.h b/src/util/sock.h
new file mode 100644
index 0000000000..0d48235043
--- /dev/null
+++ b/src/util/sock.h
@@ -0,0 +1,18 @@
+// Copyright (c) 2020-2021 The Bitcoin Core developers
+// Distributed under the MIT software license, see the accompanying
+// file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
+#ifndef BITCOIN_UTIL_SOCK_H
+#define BITCOIN_UTIL_SOCK_H
+
+#include <compat.h>
+
+#include <string>
+
+/** Return readable error string for a network error code */
+std::string NetworkErrorString(int err);
+
+/** Close socket and set hSocket to INVALID_SOCKET */
+bool CloseSocket(SOCKET& hSocket);
+
+#endif // BITCOIN_UTIL_SOCK_H