From f56ddd3fa83e186692fcc20a15432a39fa73125d Mon Sep 17 00:00:00 2001
From: Bert Belder <bertbelder@gmail.com>
Date: Mon, 9 May 2011 04:25:34 +0200
Subject: [PATCH] Implement oio_async for windows

---
 oio-win.c | 95 +++++++++++++++++++++++++++++++++++++++++++++++++++----
 oio-win.h |  6 ++++
 2 files changed, 94 insertions(+), 7 deletions(-)

diff --git a/oio-win.c b/oio-win.c
index 3bae9571..6cad3df5 100644
--- a/oio-win.c
+++ b/oio-win.c
@@ -522,6 +522,21 @@ static void oio_loop_endgame(oio_handle_t* handle) {
 }
 
 
+static void oio_async_endgame(oio_handle_t* handle) {
+  if (handle->flags & OIO_HANDLE_CLOSING &&
+      !handle->async_sent) {
+    assert(!(handle->flags & OIO_HANDLE_CLOSED));
+    handle->flags |= OIO_HANDLE_CLOSED;
+
+    if (handle->close_cb) {
+      handle->close_cb(handle, 0);
+    }
+
+    oio_refs_--;
+  }
+}
+
+
 static void oio_call_endgames() {
   oio_handle_t* handle;
 
@@ -542,6 +557,10 @@ static void oio_call_endgames() {
         oio_loop_endgame(handle);
         break;
 
+      case OIO_ASYNC:
+        oio_async_endgame(handle);
+        break;
+
       default:
         assert(0);
         break;
@@ -591,6 +610,11 @@ static int oio_close_error(oio_handle_t* handle, oio_err e) {
       oio_idle_stop(handle);
       oio_want_endgame(handle);
       return 0;
+
+    case OIO_ASYNC:
+      if (!handle->async_sent) {
+        oio_want_endgame(handle);
+      }
       return 0;
 
     default:
@@ -1119,6 +1143,50 @@ int oio_idle_stop(oio_handle_t* handle) {
 }
 
 
+int oio_async_init(oio_handle_t* handle, oio_async_cb async_cb,
+                   oio_close_cb close_cb, void* data) {
+  oio_req_t* req;
+
+  handle->type = OIO_ASYNC;
+  handle->close_cb = (void*) close_cb;
+  handle->data = data;
+  handle->flags = 0;
+  handle->async_sent = 0;
+  handle->error = oio_ok_;
+
+  req = &handle->async_req;
+  oio_req_init(req, handle, async_cb);
+  req->type = OIO_WAKEUP;
+
+  oio_refs_++;
+
+  return 0;
+}
+
+
+int oio_async_send(oio_handle_t* handle) {
+  if (handle->type != OIO_ASYNC) {
+    /* Can't set errno because that's not thread-safe. */
+    return -1;
+  }
+
+  /* The user should make sure never to call oio_async_send to a closing */
+  /* or closed handle. */
+  assert(!(handle->flags & OIO_HANDLE_CLOSING));
+
+  if (!(InterlockedOr8(&handle->async_sent, 1))) {
+    if (!PostQueuedCompletionStatus(oio_iocp_,
+                                    0,
+                                    0,
+                                    &handle->async_req.overlapped)) {
+      oio_fatal_error(GetLastError(), "PostQueuedCompletionStatus");
+    }
+  }
+
+  return 0;
+}
+
+
 static void oio_poll() {
   BOOL success;
   DWORD bytes;
@@ -1312,18 +1380,31 @@ static void oio_poll() {
         }
         break;
 
+      case OIO_WAKEUP:
+        handle->async_sent = 0;
+        if (req->cb) {
+          ((oio_async_cb)req->cb)(handle, 0);
+        }
+        if (handle->flags & OIO_HANDLE_CLOSING) {
+          oio_want_endgame(handle);
+        }
+        break;
+
       default:
         assert(0);
     }
 
-    /* The number of pending requests is now down by one */
-    handle->reqs_pending--;
+    /* TODO: reorganize this */
+    if (handle->type == OIO_TCP) {
+      /* The number of pending requests is now down by one */
+      handle->reqs_pending--;
 
-    /* Queue the handle's close callback if it is closing and there are no */
-    /* more pending requests. */
-    if (handle->flags & OIO_HANDLE_CLOSING &&
-        handle->reqs_pending == 0) {
-      oio_want_endgame(handle);
+      /* Queue the handle's close callback if it is closing and there are no */
+      /* more pending requests. */
+      if (handle->flags & OIO_HANDLE_CLOSING &&
+          handle->reqs_pending == 0) {
+        oio_want_endgame(handle);
+      }
     }
   } /* if (overlapped) */
 
diff --git a/oio-win.h b/oio-win.h
index f66b2544..e699f33b 100644
--- a/oio-win.h
+++ b/oio-win.h
@@ -81,6 +81,11 @@ typedef struct oio_buf {
   oio_handle_t* loop_next;                \
   void* loop_cb;
 
+#define oio_async_fields                  \
+  struct oio_req_s async_req;             \
+  /* char to avoid alignment issues */    \
+  char volatile async_sent;
+
 #define oio_handle_private_fields         \
   oio_handle_t* endgame_next;             \
   unsigned int flags;                     \
@@ -88,4 +93,5 @@ typedef struct oio_buf {
   union {                                 \
     struct { oio_tcp_fields  };           \
     struct { oio_loop_fields };           \
+    struct { oio_async_fields };          \
   };