Added the beginnings of our power management daemon. Currently does nothing except tell the roster to shut down when you press the power button (in conjuction with acpi_button, of course). Eventually will do things like display low power warnings, spin down hard disks, and display the requisite power info deskbar replicant.

git-svn-id: file:///srv/svn/repos/haiku/trunk/current@11466 a95241bf-73f2-0310-859d-f6bbb57e9c96

src/servers/power/power_button_monitor.cpp

@@ -0,0 +1,30 @@
+#include <Messenger.h>
+#include <Roster.h>
+
+#include "power_button_monitor.h"
+
+#define B_SYSTEM_SHUTDOWN 0x12d
+static const char *kRosterSignature = "application/x-vnd.Be-ROST";
+
+PowerButtonMonitor::PowerButtonMonitor() : BHandler ("power_button_monitor") {
+	power_button_fd = open("/dev/power/button/power",O_RDONLY);
+}
+
+PowerButtonMonitor::~PowerButtonMonitor() {
+	if (power_button_fd > 0)
+		close(power_button_fd);
+}
+
+void PowerButtonMonitor::MessageReceived(BMessage *msg) {
+	if (msg->what != POLL_POWER_BUTTON_STATUS)
+		return;
+		
+	if (power_button_fd <= 0)
+		return;
+		
+	bool button_pressed;
+	read(power_button_fd,&button_pressed,1);
+	
+	if (button_pressed)
+		BMessenger(kRosterSignature).SendMessage(B_SYSTEM_SHUTDOWN);
+}