intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 97 insertions, 0 deletions

diff --git a/util/network/pair.cpp b/util/network/pair.cpp
new file mode 100644
index 0000000000..9751ef5c96
--- /dev/null
+++ b/util/network/pair.cpp
@@ -0,0 +1,97 @@
+#include "pair.h"
+
+int SocketPair(SOCKET socks[2], bool overlapped, bool cloexec) {
+#if defined(_win_)
+    struct sockaddr_in addr;
+    SOCKET listener;
+    int e;
+    int addrlen = sizeof(addr);
+    DWORD flags = (overlapped ? WSA_FLAG_OVERLAPPED : 0) | (cloexec ? WSA_FLAG_NO_HANDLE_INHERIT : 0);
+
+    if (socks == 0) {
+        WSASetLastError(WSAEINVAL);
+
+        return SOCKET_ERROR;
+    }
+
+    socks[0] = INVALID_SOCKET;
+    socks[1] = INVALID_SOCKET;
+
+    if ((listener = socket(AF_INET, SOCK_STREAM, 0)) == INVALID_SOCKET) {
+        return SOCKET_ERROR;
+    }
+
+    memset(&addr, 0, sizeof(addr));
+    addr.sin_family = AF_INET;
+    addr.sin_addr.s_addr = htonl(0x7f000001);
+    addr.sin_port = 0;
+
+    e = bind(listener, (const struct sockaddr*)&addr, sizeof(addr));
+
+    if (e == SOCKET_ERROR) {
+        e = WSAGetLastError();
+        closesocket(listener);
+        WSASetLastError(e);
+
+        return SOCKET_ERROR;
+    }
+
+    e = getsockname(listener, (struct sockaddr*)&addr, &addrlen);
+
+    if (e == SOCKET_ERROR) {
+        e = WSAGetLastError();
+        closesocket(listener);
+        WSASetLastError(e);
+
+        return SOCKET_ERROR;
+    }
+
+    do {
+        if (listen(listener, 1) == SOCKET_ERROR)
+            break;
+
+        if ((socks[0] = WSASocket(AF_INET, SOCK_STREAM, 0, nullptr, 0, flags)) == INVALID_SOCKET)
+            break;
+
+        if (connect(socks[0], (const struct sockaddr*)&addr, sizeof(addr)) == SOCKET_ERROR)
+            break;
+
+        if ((socks[1] = accept(listener, nullptr, nullptr)) == INVALID_SOCKET)
+            break;
+
+        closesocket(listener);
+
+        return 0;
+    } while (0);
+
+    e = WSAGetLastError();
+    closesocket(listener);
+    closesocket(socks[0]);
+    closesocket(socks[1]);
+    WSASetLastError(e);
+
+    return SOCKET_ERROR;
+#else
+    (void)overlapped;
+
+    #if defined(_linux_)
+    return socketpair(AF_LOCAL, SOCK_STREAM | (cloexec ? SOCK_CLOEXEC : 0), 0, socks);
+    #else
+    int r = socketpair(AF_LOCAL, SOCK_STREAM, 0, socks);
+    // Non-atomic wrt exec
+    if (r == 0 && cloexec) {
+        for (int i = 0; i < 2; ++i) {
+            int flags = fcntl(socks[i], F_GETFD, 0);
+            if (flags < 0) {
+                return flags;
+            }
+            r = fcntl(socks[i], F_SETFD, flags | FD_CLOEXEC);
+            if (r < 0) {
+                return r;
+            }
+        }
+    }
+    return r;
+    #endif
+#endif
+}