Switch to using internal event API for QEMU driver

ChangeLog

+Tue Jun 26 18:47:00 EST 2007 Daniel P. Berrange <berrange@redhat.com>
+
+	* src/event.h, src/event.c, src/Makefile.am, src/libvirt_sym.version:
+	Provide an internal API for drivers to register callbacks for
+	monitoring file handles & generating timer notifications.
+	* qemud/driver.c, qemud/event.c, qemud/event.h, qemud/qemud.c:
+	Adapt to make use of internal driver API for events.
+
 Tue Jun 26 18:41:00 EST 2007 Daniel P. Berrange <berrange@redhat.com>
 
 	* qemud/conf.c, qemud/conf.h, qemud/dispatch.c, qemud/driver.c,

docs/apibuild.py

@@ -49,6 +49,8 @@ ignored_files = {
   "conf.c": "internal code",
   "console.h": "internal code",
   "console.c": "internal code",
+  "event.h": "internal code",
+  "event.c": "internal code",
 }
 
 ignored_words = {

qemud/driver.c

@@ -81,6 +81,9 @@ static int qemudSetNonBlock(int fd) {
 }
 
 
+#define virEventAddHandle(fd, events, cb, opaque) virEventAddHandleImpl(fd, events, cb, opaque)
+#define virEventRemoveHandle(fd) virEventRemoveHandleImpl(fd)
+
 
 static void qemudDispatchVMEvent(int fd, int events, void *opaque);
 int qemudStartVMDaemon(struct qemud_driver *driver,

qemud/event.c

@@ -76,7 +76,7 @@ static int nextTimer = 0;
  * NB, it *must* be safe to call this from within a callback
  * For this reason we only ever append to existing list.
  */
-int virEventAddHandle(int fd, int events, virEventHandleCallback cb, void *opaque) {
+int virEventAddHandleImpl(int fd, int events, virEventHandleCallback cb, void *opaque) {
     qemudDebug("Add handle %d %d %p %p\n", fd, events, cb, opaque);
     if (eventLoop.handlesCount == eventLoop.handlesAlloc) {
         struct virEventHandle *tmp;
@@ -109,7 +109,7 @@ int virEventAddHandle(int fd, int events, virEventHandleCallback cb, void *opaqu
  * For this reason we only ever set a flag in the existing list.
  * Actual deletion will be done out-of-band
  */
-int virEventRemoveHandle(int fd) {
+int virEventRemoveHandleImpl(int fd) {
     int i;
     qemudDebug("Remove handle %d\n", fd);
     for (i = 0 ; i < eventLoop.handlesCount ; i++) {
@@ -131,7 +131,7 @@ int virEventRemoveHandle(int fd) {
  * NB, it *must* be safe to call this from within a callback
  * For this reason we only ever append to existing list.
  */
-int virEventAddTimeout(int timeout, virEventTimeoutCallback cb, void *opaque) {
+int virEventAddTimeoutImpl(int timeout, virEventTimeoutCallback cb, void *opaque) {
     struct timeval tv;
     qemudDebug("Adding timeout with %d ms period", timeout);
     if (gettimeofday(&tv, NULL) < 0) {
@@ -173,7 +173,7 @@ int virEventAddTimeout(int timeout, virEventTimeoutCallback cb, void *opaque) {
  * For this reason we only ever set a flag in the existing list.
  * Actual deletion will be done out-of-band
  */
-int virEventRemoveTimeout(int timer) {
+int virEventRemoveTimeoutImpl(int timer) {
     int i;
     for (i = 0 ; i < eventLoop.timeoutsCount ; i++) {
         if (eventLoop.timeouts[i].deleted)

qemud/event.h

@@ -24,18 +24,10 @@
 #ifndef __VIRTD_EVENT_H__
 #define __VIRTD_EVENT_H__
 
+#include "../src/event.h"
 
 /**
- * virEventHandleCallback: callback for receiving file handle events
- *
- * @fd: file handle on which the event occured
- * @events: bitset of events from POLLnnn constants
- * @opaque: user data registered with handle
- */
-typedef void (*virEventHandleCallback)(int fd, int events, void *opaque);
-
-/**
- * virEventAddHandle: register a callback for monitoring file handle events
+ * virEventAddHandleImpl: register a callback for monitoring file handle events
  *
  * @fd: file handle to monitor for events
  * @events: bitset of events to wach from POLLnnn constants
@@ -44,27 +36,19 @@ typedef void (*virEventHandleCallback)(int fd, int events, void *opaque);
  *
  * returns -1 if the file handle cannot be registered, 0 upon success
  */
-int virEventAddHandle(int fd, int events, virEventHandleCallback cb, void *opaque);
+int virEventAddHandleImpl(int fd, int events, virEventHandleCallback cb, void *opaque);
 
 /**
- * virEventRemoveHandle: unregister a callback from a file handle
+ * virEventRemoveHandleImpl: unregister a callback from a file handle
  *
  * @fd: file handle to stop monitoring for events
  *
  * returns -1 if the file handle was not registered, 0 upon success
  */
-int virEventRemoveHandle(int fd);
+int virEventRemoveHandleImpl(int fd);
 
 /**
- * virEventTimeoutCallback: callback for receiving timer events
- *
- * @timer: timer id emitting the event
- * @opaque: user data registered with handle
- */
-typedef void (*virEventTimeoutCallback)(int timer, void *opaque);
-
-/**
- * virEventAddTimeout: register a callback for a timer event
+ * virEventAddTimeoutImpl: register a callback for a timer event
  *
  * @timeout: timeout between events in milliseconds
  * @cb: callback to invoke when an event occurrs
@@ -73,17 +57,16 @@ typedef void (*virEventTimeoutCallback)(int timer, void *opaque);
  * returns -1 if the file handle cannot be registered, a positive
  * integer timer id upon success
  */
-int virEventAddTimeout(int timeout, virEventTimeoutCallback cb, void *opaque);
+int virEventAddTimeoutImpl(int timeout, virEventTimeoutCallback cb, void *opaque);
 
 /**
- * virEventRemoveTimeout: unregister a callback for a timer
+ * virEventRemoveTimeoutImpl: unregister a callback for a timer
  *
  * @timer: the timer id to remove
  *
  * returns -1 if the timer was not registered, 0 upon success
  */
-int virEventRemoveTimeout(int timer);
-
+int virEventRemoveTimeoutImpl(int timer);
 
 /**
  * virEventRunOnce: run a single iteration of the event loop.

qemud/qemud.c

@@ -471,10 +471,10 @@ static int qemudListenUnix(struct qemud_server *server,
         goto cleanup;
     }
 
-    if (virEventAddHandle(sock->fd,
-                          POLLIN| POLLERR | POLLHUP,
-                          qemudDispatchServerEvent,
-                          server) < 0) {
+    if (virEventAddHandleImpl(sock->fd,
+                              POLLIN| POLLERR | POLLHUP,
+                              qemudDispatchServerEvent,
+                              server) < 0) {
         qemudLog(QEMUD_ERR, "Failed to add server event callback");
         goto cleanup;
     }
@@ -584,10 +584,10 @@ remoteListenTCP (struct qemud_server *server,
             return -1;
         }
 
-        if (virEventAddHandle(sock->fd,
-                              POLLIN| POLLERR | POLLHUP,
-                              qemudDispatchServerEvent,
-                              server) < 0) {
+        if (virEventAddHandleImpl(sock->fd,
+                                  POLLIN| POLLERR | POLLHUP,
+                                  qemudDispatchServerEvent,
+                                  server) < 0) {
             qemudLog(QEMUD_ERR, "Failed to add server event callback");
             return -1;
         }
@@ -1056,7 +1056,7 @@ static void qemudDispatchClientFailure(struct qemud_server *server, struct qemud
         tmp = tmp->next;
     }
 
-    virEventRemoveHandle(client->fd);
+    virEventRemoveHandleImpl(client->fd);
 
     if (client->tls && client->session) gnutls_deinit (client->session);
     close(client->fd);
@@ -1418,22 +1418,22 @@ static int qemudRegisterClientEvent(struct qemud_server *server,
                                     struct qemud_client *client,
                                     int removeFirst) {
     if (removeFirst)
-        if (virEventRemoveHandle(client->fd) < 0)
+        if (virEventRemoveHandleImpl(client->fd) < 0)
             return -1;
 
     if (client->tls) {
-        if (virEventAddHandle(client->fd,
-                              (client->direction ?
-                               POLLOUT : POLLIN) | POLLERR | POLLHUP,
-                              qemudDispatchClientEvent,
-                              server) < 0)
+        if (virEventAddHandleImpl(client->fd,
+                                  (client->direction ?
+                                   POLLOUT : POLLIN) | POLLERR | POLLHUP,
+                                  qemudDispatchClientEvent,
+                                  server) < 0)
             return -1;
     } else {
-        if (virEventAddHandle(client->fd,
-                              (client->mode == QEMUD_MODE_TX_PACKET ?
-                               POLLOUT : POLLIN) | POLLERR | POLLHUP,
-                              qemudDispatchClientEvent,
-                              server) < 0)
+        if (virEventAddHandleImpl(client->fd,
+                                  (client->mode == QEMUD_MODE_TX_PACKET ?
+                                   POLLOUT : POLLIN) | POLLERR | POLLHUP,
+                                  qemudDispatchClientEvent,
+                                  server) < 0)
             return -1;
     }
 
@@ -1864,10 +1864,10 @@ int main(int argc, char **argv) {
         goto error2;
     }
 
-    if (virEventAddHandle(sigpipe[0],
-                          POLLIN,
-                          qemudDispatchSignalEvent,
-                          server) < 0) {
+    if (virEventAddHandleImpl(sigpipe[0],
+                              POLLIN,
+                              qemudDispatchSignalEvent,
+                              server) < 0) {
         qemudLog(QEMUD_ERR, "Failed to register callback for signal pipe");
         ret = 3;
         goto error2;

src/Makefile.am

@@ -31,6 +31,7 @@ CLIENT_SOURCES =						\
 		test.c test.h                                   \
                 buf.c buf.h					\
 		xml.c xml.h					\
+		event.c event.h					\
 		xen_unified.c xen_unified.h			\
 		xen_internal.c xen_internal.h			\
 		xs_internal.c xs_internal.h			\

src/event.c

+/*
+ * event.h: event loop for monitoring file handles
+ *
+ * Copyright (C) 2007 Daniel P. Berrange
+ * Copyright (C) 2007 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA
+ *
+ * Author: Daniel P. Berrange <berrange@redhat.com>
+ */
+
+
+#include "event.h"
+
+#include <stdlib.h>
+
+static virEventAddHandleFunc addHandleImpl = NULL;
+static virEventRemoveHandleFunc removeHandleImpl = NULL;
+static virEventAddTimeoutFunc addTimeoutImpl = NULL;
+static virEventRemoveTimeoutFunc removeTimeoutImpl = NULL;
+
+int virEventAddHandle(int fd, int events, virEventHandleCallback cb, void *opaque) {
+    if (!addHandleImpl)
+        return -1;
+
+    return addHandleImpl(fd, events, cb, opaque);
+}
+
+int virEventRemoveHandle(int fd) {
+    if (!removeHandleImpl)
+        return -1;
+
+    return removeHandleImpl(fd);
+}
+
+int virEventAddTimeout(int timeout, virEventTimeoutCallback cb, void *opaque) {
+    if (!addTimeoutImpl)
+        return -1;
+
+    return addTimeoutImpl(timeout, cb, opaque);
+}
+
+int virEventRemoveTimeout(int timer) {
+    if (!removeTimeoutImpl)
+        return -1;
+
+    return removeTimeoutImpl(timer);
+}
+
+void __virEventRegisterImpl(virEventAddHandleFunc addHandle,
+                           virEventRemoveHandleFunc removeHandle,
+                           virEventAddTimeoutFunc addTimeout,
+                           virEventRemoveTimeoutFunc removeTimeout) {
+    addHandleImpl = addHandle;
+    removeHandleImpl = removeHandle;
+    addTimeoutImpl = addTimeout;
+    removeTimeoutImpl = removeTimeout;
+}
+
+
+/*
+ * Local variables:
+ *  indent-tabs-mode: nil
+ *  c-indent-level: 4
+ *  c-basic-offset: 4
+ *  tab-width: 4
+ * End:
+ */

src/event.h

+/*
+ * event.h: event loop for monitoring file handles
+ *
+ * Copyright (C) 2007 Daniel P. Berrange
+ * Copyright (C) 2007 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307  USA
+ *
+ * Author: Daniel P. Berrange <berrange@redhat.com>
+ */
+
+#ifndef __VIR_EVENT_H__
+#define __VIR_EVENT_H__
+
+
+/**
+ * virEventHandleCallback: callback for receiving file handle events
+ *
+ * @fd: file handle on which the event occured
+ * @events: bitset of events from POLLnnn constants
+ * @opaque: user data registered with handle
+ */
+typedef void (*virEventHandleCallback)(int fd, int events, void *opaque);
+
+/**
+ * virEventAddHandle: register a callback for monitoring file handle events
+ *
+ * @fd: file handle to monitor for events
+ * @events: bitset of events to wach from POLLnnn constants
+ * @cb: callback to invoke when an event occurrs
+ * @opaque: user data to pass to callback
+ *
+ * returns -1 if the file handle cannot be registered, 0 upon success
+ */
+int virEventAddHandle(int fd, int events, virEventHandleCallback cb, void *opaque);
+
+/**
+ * virEventRemoveHandle: unregister a callback from a file handle
+ *
+ * @fd: file handle to stop monitoring for events
+ *
+ * returns -1 if the file handle was not registered, 0 upon success
+ */
+int virEventRemoveHandle(int fd);
+
+/**
+ * virEventTimeoutCallback: callback for receiving timer events
+ *
+ * @timer: timer id emitting the event
+ * @opaque: user data registered with handle
+ */
+typedef void (*virEventTimeoutCallback)(int timer, void *opaque);
+
+/**
+ * virEventAddTimeout: register a callback for a timer event
+ *
+ * @timeout: timeout between events in milliseconds
+ * @cb: callback to invoke when an event occurrs
+ * @opaque: user data to pass to callback
+ *
+ * returns -1 if the file handle cannot be registered, a positive
+ * integer timer id upon success
+ */
+int virEventAddTimeout(int timeout, virEventTimeoutCallback cb, void *opaque);
+
+/**
+ * virEventRemoveTimeout: unregister a callback for a timer
+ *
+ * @timer: the timer id to remove
+ *
+ * returns -1 if the timer was not registered, 0 upon success
+ */
+int virEventRemoveTimeout(int timer);
+
+typedef int (*virEventAddHandleFunc)(int, int, virEventHandleCallback, void *);
+typedef int (*virEventRemoveHandleFunc)(int);
+
+typedef int (*virEventAddTimeoutFunc)(int, virEventTimeoutCallback, void *);
+typedef int (*virEventRemoveTimeoutFunc)(int);
+
+void __virEventRegisterImpl(virEventAddHandleFunc addHandle,
+			    virEventRemoveHandleFunc removeHandle,
+			    virEventAddTimeoutFunc addTimeout,
+			    virEventRemoveTimeoutFunc removeTimeout);
+
+#define virEventRegisterImpl(ah,rh,at,rt) __virEventRegisterImpl(ah,rh,at,rt)
+
+#endif /* __VIR_EVENT_H__ */

src/libvirt_sym.version

@@ -91,6 +91,12 @@
 	virNetworkGetAutostart;
 	virNetworkSetAutostart;
 
+        /* Symbols with __ are private only
+           for use by the libvirtd daemon.
+           They are not part of stable ABI
+           guarentee provided for the public
+           symbols above */
+
 	__virConfNew;
 	__virConfReadFile;
 	__virConfReadMem;
@@ -103,5 +109,7 @@
 	__virGetDomain;
 	__virGetNetwork;
 
+	__virEventRegisterImpl;
+
     local: *;
 };