Add driver API for global startup/shutdown/reload hooks

ChangeLog

+Tue Jun 26 18:53:00 EST 2007 Daniel P. Berrange <berrange@redhat.com>
+
+	* src/internal.h, src/libvirt.c, src/driver.h, src/libvirt_sym.version
+	Added internal driver API hooks for global shutdown/startup/reload
+	* qemud/driver.c, qemud/driver.h, qemud/internal.h, qemud/qemud.c
+	Adapt to make use of new driver API for startup/shutdown
+
 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:

qemud/driver.c

@@ -205,7 +205,7 @@ int qemudStartup(void) {
     return -1;
 }
 
-void qemudReload(void) {
+int qemudReload(void) {
     qemudScanConfigs(qemu_driver);
 
      if (qemu_driver->iptables) {
@@ -214,14 +214,28 @@ void qemudReload(void) {
     }
 
     qemudAutostartConfigs(qemu_driver);
+
+    return 0;
 }
 
-void qemudShutdown() {
+int qemudActive(void) {
+    /* If we've any active networks or guests, then we
+     * mark this driver as active
+     */
+    if (qemu_driver->nactivenetworks &&
+        qemu_driver->nactivevms)
+        return 1;
+
+    /* Otherwise we're happy to deal with a shutdown */
+    return 0;
+}
+
+int qemudShutdown() {
     struct qemud_vm *vm;
     struct qemud_network *network;
 
     if (!qemu_driver)
-        return;
+        return -1;
 
     /* shutdown active VMs */
     vm = qemu_driver->vms;
@@ -279,6 +293,8 @@ void qemudShutdown() {
 
     free(qemu_driver);
     qemu_driver = NULL;
+
+    return 0;
 }
 
 static int
@@ -2516,6 +2532,12 @@ static virNetworkDriver qemuNetworkDriver = {
     qemudNetworkSetAutostart, /* networkSetAutostart */
 };
 
+static virStateDriver qemuStateDriver = {
+    qemudStartup,
+    qemudShutdown,
+    qemudReload,
+    qemudActive,
+};
 
 /*
  * Local variables:

qemud/driver.h

@@ -29,8 +29,9 @@
 #include "../src/internal.h"
 
 int qemudStartup(void);
-void qemudReload(void);
-void qemudShutdown(void);
+int qemudReload(void);
+int qemudShutdown(void);
+int qemudActive(void);
 
 
 virDrvOpenStatus qemudOpen(virConnectPtr conn,

qemud/internal.h

@@ -34,6 +34,7 @@
 #include "remote_protocol.h"
 #include "bridge.h"
 #include "iptables.h"
+#include "../config.h"
 
 #ifdef __GNUC__
 #ifdef HAVE_ANSIDECL_H

qemud/qemud.c

@@ -54,6 +54,7 @@
 #include <libvirt/virterror.h>
 
 #include "internal.h"
+#include "../src/internal.h"
 #include "../src/remote_internal.h"
 #include "../src/conf.h"
 #include "dispatch.h"
@@ -206,6 +207,9 @@ static void qemudDispatchSignalEvent(int fd ATTRIBUTE_UNUSED,
     switch (sigc) {
     case SIGHUP:
         qemudLog(QEMUD_INFO, "Reloading configuration on SIGHUP");
+        if (virStateReload() < 0)
+            qemudLog(QEMUD_WARN, "Error while reloading drivers");
+
         if (!remote) {
             qemudReload();
         }
@@ -704,6 +708,8 @@ static struct qemud_server *qemudInitialize(int sigread) {
     if (roSockname[0] != '\0' && qemudListenUnix(server, roSockname, 1) < 0)
         goto cleanup;
 
+    virStateInitialize();
+
     if (!remote) /* qemud only */ {
         if (qemudStartup() < 0) {
             goto cleanup;
@@ -1478,13 +1484,45 @@ static int qemudOneLoop(void) {
     return 0;
 }
 
+static void qemudInactiveTimer(int timer ATTRIBUTE_UNUSED, void *data) {
+    struct qemud_server *server = (struct qemud_server *)data;
+    qemudDebug("Got inactive timer expiry");
+    if (!virStateActive()) {
+        qemudDebug("No state active, shutting down");
+        server->shutdown = 1;
+    }
+}
+
 static int qemudRunLoop(struct qemud_server *server) {
-    int ret;
+    int timerid = -1;
+
+    for (;;) {
+        /* A shutdown timeout is specified, so check
+         * if any drivers have active state, if not
+         * shutdown after timeout seconds
+         */
+        if (timeout > 0 && !virStateActive() && !server->clients) {
+            timerid = virEventAddTimeoutImpl(timeout*1000, qemudInactiveTimer, server);
+            qemudDebug("Scheduling shutdown timer %d", timerid);
+        }
+
+        if (qemudOneLoop() < 0)
+            break;
 
-    while ((ret = qemudOneLoop()) == 0 && !server->shutdown)
-        ;
+        /* Unregister any timeout that's active, since we
+         * just had an event processed
+         */
+        if (timerid != -1) {
+            qemudDebug("Removing shutdown timer %d", timerid);
+            virEventRemoveTimeoutImpl(timerid);
+            timerid = -1;
+        }
 
-    return ret == -1 ? -1 : 0;
+        if (server->shutdown)
+            return 0;
+    }
+
+    return -1;
 }
 
 static void qemudCleanup(struct qemud_server *server) {
@@ -1502,6 +1540,7 @@ static void qemudCleanup(struct qemud_server *server) {
 
 
     qemudShutdown();
+    virStateCleanup();
 
     free(server);
 }

src/driver.h

@@ -322,6 +322,20 @@ struct _virNetworkDriver {
 	virDrvNetworkSetAutostart	networkSetAutostart;
 };
 
+typedef int (*virDrvStateInitialize) (void);
+typedef int (*virDrvStateCleanup) (void);
+typedef int (*virDrvStateReload) (void);
+typedef int (*virDrvStateActive) (void);
+
+typedef struct _virStateDriver virStateDriver;
+typedef virStateDriver *virStateDriverPtr;
+
+struct _virStateDriver {
+    virDrvStateInitialize  initialize;
+    virDrvStateCleanup     cleanup;
+    virDrvStateReload      reload;
+    virDrvStateActive      active;
+};
 
 /*
  * Registration
@@ -330,6 +344,7 @@ struct _virNetworkDriver {
  */
 int virRegisterDriver(virDriverPtr);
 int virRegisterNetworkDriver(virNetworkDriverPtr);
+int virRegisterStateDriver(virStateDriverPtr);
 
 #ifdef __cplusplus
 }

src/internal.h

@@ -220,6 +220,15 @@ int		virFreeNetwork	(virConnectPtr conn,
 #define virGetDomain(c,n,u) __virGetDomain((c),(n),(u))
 #define virGetNetwork(c,n,u) __virGetNetwork((c),(n),(u))
 
+int __virStateInitialize(void);
+int __virStateCleanup(void);
+int __virStateReload(void);
+int __virStateActive(void);
+#define virStateInitialize() __virStateInitialize()
+#define virStateCleanup() __virStateCleanup()
+#define virStateReload() __virStateReload()
+#define virStateActive() __virStateActive()
+
 #ifdef __cplusplus
 }
 #endif                          /* __cplusplus */

src/libvirt.c

@@ -40,6 +40,8 @@ static virDriverPtr virDriverTab[MAX_DRIVERS];
 static int virDriverTabCount = 0;
 static virNetworkDriverPtr virNetworkDriverTab[MAX_DRIVERS];
 static int virNetworkDriverTabCount = 0;
+static virStateDriverPtr virStateDriverTab[MAX_DRIVERS];
+static int virStateDriverTabCount = 0;
 static int initialized = 0;
 
 /**
@@ -240,6 +242,79 @@ virRegisterDriver(virDriverPtr driver)
     return virDriverTabCount++;
 }
 
+/**
+ * virRegisterStateDriver:
+ * @driver: pointer to a driver block
+ *
+ * Register a virtualization driver
+ *
+ * Returns the driver priority or -1 in case of error.
+ */
+int
+virRegisterStateDriver(virStateDriverPtr driver)
+{
+    if (virInitialize() < 0)
+      return -1;
+
+    if (driver == NULL) {
+        virLibConnError(NULL, VIR_ERR_INVALID_ARG, __FUNCTION__);
+        return(-1);
+    }
+
+    if (virStateDriverTabCount >= MAX_DRIVERS) {
+    	virLibConnError(NULL, VIR_ERR_INVALID_ARG, __FUNCTION__);
+        return(-1);
+    }
+
+    virStateDriverTab[virStateDriverTabCount] = driver;
+    return virStateDriverTabCount++;
+}
+
+int __virStateInitialize(void) {
+    int i, ret = 0;
+
+    if (virInitialize() < 0)
+        return -1;
+
+    for (i = 0 ; i < virStateDriverTabCount ; i++) {
+        if (virStateDriverTab[i]->initialize() < 0)
+            ret = -1;
+    }
+    return ret;
+}
+
+int __virStateCleanup(void) {
+    int i, ret = 0;
+
+    for (i = 0 ; i < virStateDriverTabCount ; i++) {
+        if (virStateDriverTab[i]->cleanup() < 0)
+            ret = -1;
+    }
+    return ret;
+}
+
+int __virStateReload(void) {
+    int i, ret = 0;
+
+    for (i = 0 ; i < virStateDriverTabCount ; i++) {
+        if (virStateDriverTab[i]->reload() < 0)
+            ret = -1;
+    }
+    return ret;
+}
+
+int __virStateActive(void) {
+    int i, ret = 0;
+
+    for (i = 0 ; i < virStateDriverTabCount ; i++) {
+        if (virStateDriverTab[i]->active())
+            ret = 1;
+    }
+    return ret;
+}
+
+
+
 /**
  * virGetVersion:
  * @libVer: return value for the library version (OUT)

src/libvirt_sym.version

@@ -111,5 +111,10 @@
 
 	__virEventRegisterImpl;
 
+ 	__virStateInitialize;
+ 	__virStateCleanup;
+ 	__virStateReload;
+ 	__virStateActive;
+
     local: *;
 };