From 216176f588f4a4616bc129ccf5255734c8b1fe93 Mon Sep 17 00:00:00 2001
From: Amit Shah <amit.shah@redhat.com>
Date: Mon, 21 Mar 2011 20:32:58 +0100
Subject: [PATCH] iohandlers: Add enable/disable_write_fd_handler() functions

These will be used to provide a cleaner API for the nonblocking case.

Signed-off-by: Amit Shah <amit.shah@redhat.com>
---
 iohandler.c | 35 +++++++++++++++++++++++++++++++++++
 main-loop.h |  3 +++
 2 files changed, 38 insertions(+)

diff --git a/iohandler.c b/iohandler.c
index 5640d49..a9a62cb 100644
--- a/iohandler.c
+++ b/iohandler.c
@@ -45,6 +45,41 @@ typedef struct IOHandlerRecord {
 static QLIST_HEAD(, IOHandlerRecord) io_handlers =
     QLIST_HEAD_INITIALIZER(io_handlers);
 
+static IOHandlerRecord *find_iohandler(int fd)
+{
+    IOHandlerRecord *ioh;
+
+    QLIST_FOREACH(ioh, &io_handlers, next) {
+        if (ioh->fd == fd) {
+            return ioh;
+        }
+    }
+    return NULL;
+}
+
+void enable_write_fd_handler(int fd, IOHandler *fd_write)
+{
+    IOHandlerRecord *ioh;
+
+    ioh = find_iohandler(fd);
+    if (!ioh) {
+        return;
+    }
+
+    ioh->fd_write = fd_write;
+}
+
+void disable_write_fd_handler(int fd)
+{
+    IOHandlerRecord *ioh;
+
+    ioh = find_iohandler(fd);
+    if (!ioh) {
+        return;
+    }
+
+    ioh->fd_write = NULL;
+}
 
 /* XXX: fd_read_poll should be suppressed, but an API change is
    necessary in the character devices to suppress fd_can_read(). */
diff --git a/main-loop.h b/main-loop.h
index 8a716b1..c5a96cd 100644
--- a/main-loop.h
+++ b/main-loop.h
@@ -167,6 +167,9 @@ typedef void IOReadHandler(void *opaque, const uint8_t *buf, int size);
 typedef int IOCanReadHandler(void *opaque);
 typedef void IOHandler(void *opaque);
 
+void enable_write_fd_handler(int fd, IOHandler *fd_write);
+void disable_write_fd_handler(int fd);
+
 /**
  * qemu_set_fd_handler2: Register a file descriptor with the main loop
  *