[wpinet] Move network portions of wpiutil into new wpinet library (#4077)

wpinet/src/main/native/cpp/raw_socket_ostream.cpp

@@ -0,0 +1,42 @@
+// Copyright (c) FIRST and other WPILib contributors.
+// Open Source Software; you can modify and/or share it under the terms of
+// the WPILib BSD license file in the root directory of this project.
+
+#include "wpinet/raw_socket_ostream.h"
+
+#include "wpinet/NetworkStream.h"
+
+using namespace wpi;
+
+raw_socket_ostream::~raw_socket_ostream() {
+  flush();
+  if (m_shouldClose) {
+    close();
+  }
+}
+
+void raw_socket_ostream::write_impl(const char* data, size_t len) {
+  size_t pos = 0;
+
+  while (pos < len) {
+    NetworkStream::Error err;
+    size_t count = m_stream.send(&data[pos], len - pos, &err);
+    if (count == 0) {
+      error_detected();
+      return;
+    }
+    pos += count;
+  }
+}
+
+uint64_t raw_socket_ostream::current_pos() const {
+  return 0;
+}
+
+void raw_socket_ostream::close() {
+  if (!m_shouldClose) {
+    return;
+  }
+  flush();
+  m_stream.close();
+}