From 53ddb39e1916d1546e98e5dc0570f8e78e61c7d1 Mon Sep 17 00:00:00 2001
From: baldurk <baldurk@baldurk.org>
Date: Mon, 27 Nov 2017 18:50:49 +0000
Subject: [PATCH] Add non-blocking recv function to Socket class

---
 renderdoc/os/os_specific.h           |  1 +
 renderdoc/os/posix/posix_network.cpp | 32 ++++++++++++++++++++++++++++
 renderdoc/os/win32/win32_network.cpp | 32 ++++++++++++++++++++++++++++
 3 files changed, 65 insertions(+)

diff --git a/renderdoc/os/os_specific.h b/renderdoc/os/os_specific.h
index 0452d1926..0fe24ab7a 100644
--- a/renderdoc/os/os_specific.h
+++ b/renderdoc/os/os_specific.h
@@ -147,6 +147,7 @@ public:
 
   bool SendDataBlocking(const void *buf, uint32_t length);
   bool RecvDataBlocking(void *data, uint32_t length);
+  bool RecvDataNonBlocking(void *data, uint32_t &length);
 
 private:
   ptrdiff_t socket;
diff --git a/renderdoc/os/posix/posix_network.cpp b/renderdoc/os/posix/posix_network.cpp
index 2937bf95e..82d967eed 100644
--- a/renderdoc/os/posix/posix_network.cpp
+++ b/renderdoc/os/posix/posix_network.cpp
@@ -183,6 +183,38 @@ bool Socket::IsRecvDataWaiting()
   return ret > 0;
 }
 
+bool Socket::RecvDataNonBlocking(void *buf, uint32_t &length)
+{
+  if(length == 0)
+    return true;
+
+  // socket is already blocking, don't have to change anything
+  int ret = recv(socket, (char *)buf, length, 0);
+
+  if(ret > 0)
+  {
+    length = (uint32_t)ret;
+  }
+  else
+  {
+    length = 0;
+    int err = errno;
+
+    if(err == EWOULDBLOCK || err == EAGAIN)
+    {
+      return true;
+    }
+    else
+    {
+      RDCWARN("recv: %d", err);
+      Shutdown();
+      return false;
+    }
+  }
+
+  return true;
+}
+
 bool Socket::RecvDataBlocking(void *buf, uint32_t length)
 {
   if(length == 0)
diff --git a/renderdoc/os/win32/win32_network.cpp b/renderdoc/os/win32/win32_network.cpp
index 4727ec02f..3c4e44135 100644
--- a/renderdoc/os/win32/win32_network.cpp
+++ b/renderdoc/os/win32/win32_network.cpp
@@ -184,6 +184,38 @@ bool Socket::IsRecvDataWaiting()
   return ret > 0;
 }
 
+bool Socket::RecvDataNonBlocking(void *buf, uint32_t &length)
+{
+  if(length == 0)
+    return true;
+
+  // socket is already blocking, don't have to change anything
+  int ret = recv(socket, (char *)buf, length, 0);
+
+  if(ret > 0)
+  {
+    length = (uint32_t)ret;
+  }
+  else
+  {
+    length = 0;
+    int err = WSAGetLastError();
+
+    if(err == WSAEWOULDBLOCK)
+    {
+      return true;
+    }
+    else
+    {
+      RDCWARN("recv: %d", err);
+      Shutdown();
+      return false;
+    }
+  }
+
+  return true;
+}
+
 bool Socket::RecvDataBlocking(void *buf, uint32_t length)
 {
   if(length == 0)