client: Revise Apple idle time detection for compatibility with OS 10.6

svn path=/trunk/boinc/; revision=17432

checkin_notes

@@ -2506,3 +2506,11 @@ David  2 Mar 2009
     sched/
         sched_config.cpp,h
         sched_locality.cpp
+
+Charlie 2 Mar 2009
+    - client: Revise Apple idle time detection for compatibility with OS 10.6.
+
+    client/
+        hostinfo_unix.cpp
+    lib/
+        hostinfo.h

client/hostinfo_unix.cpp

@@ -125,7 +125,8 @@ extern "C" {
 }    // extern "C"
 #endif
 
-NXEventHandle gEventHandle = NULL;
+mach_port_t gEventHandle = NULL;
+#include "util.h"
 #endif  // __APPLE__
 
 #ifdef _HPUX_SOURCE
@@ -1078,20 +1079,86 @@ inline bool user_idle(time_t t, struct utmp* u) {
 
 #ifdef __APPLE__
 
+// NXIdleTime() is an undocumented Apple API to return user idle time, which 
+// was implemented from before OS 10.0 through OS 10.5.  In OS 10.4, Apple 
+// added the CGEventSourceSecondsSinceLastEventType() API as a replacement for 
+// NXIdleTime().  However, BOINC could not use this newer API when configured 
+// as a pre-login launchd daemon unless that daemon was running as root, 
+// because it could not connect to the Window Server.  So BOINC continued to 
+// use NXIdleTime().  
+//
+// In OS 10.6, Apple removed the NXIdleTime() API.  BOINC can instead use the 
+// IOHIDGetParameter() API in OS 10.6.  When BOINC is a pre-login launchd 
+// daemon running as user boinc_master, this API works properly under OS 10.6 
+// but fails under OS 10.5 and earlier.
+//
+// So we use weak-linking of NxIdleTime() to prevent a run-time crash from the 
+// dynamic linker, and use the IOHIDGetParameter() API if NXIdleTime does not 
+// exist.
+//
 bool HOST_INFO::users_idle(
     bool check_all_logins, double idle_time_to_run, double *actual_idle_time
 ) {
-    double idleTime = 0;
-      
-    if (gEventHandle) {
-        idleTime = NXIdleTime(gEventHandle);    
-    } else {
-        // Initialize Mac OS X idle time measurement / idle detection
-        // Do this here because NXOpenEventStatus() may not be available 
-        // immediately on system startup when running as a deaemon.
-        gEventHandle = NXOpenEventStatus();
-    }
+    static double   init_time = 0;
+    static bool     error_posted = false;
+    double          idleTime = 0;
+    io_service_t    service;
+    kern_return_t   kernResult; 
+    UInt64          params;
+    IOByteCount     rcnt = sizeof(UInt64);
     
+    if (init_time == 0) init_time = dtime();
+        
+    if (NXIdleTime) {   // Use NXIdleTime API in OS 10.5 and earlier
+        if (gEventHandle) {
+            idleTime = NXIdleTime(gEventHandle);    
+        } else {
+            // Initialize Mac OS X idle time measurement / idle detection
+            // Do this here because NXOpenEventStatus() may not be available 
+            // immediately on system startup when running as a deaemon.
+            if ((dtime() - init_time) > 180) {              // Limit retries to 180 seconds
+                
+                 msg_printf(NULL, MSG_USER_ERROR,
+                    "User idle detection is disabled: initialization failed."
+                );
+                goto bail;
+            }
+            
+            gEventHandle = NXOpenEventStatus();
+        }
+    } else {        // NXIdleTime API does not exist in OS 10.6 and later
+        if (gEventHandle) {
+            kernResult = IOHIDGetParameter( gEventHandle, CFSTR(EVSIOIDLE), sizeof(UInt64), &params, &rcnt );
+            if ( kernResult != kIOReturnSuccess ) {
+                if (!error_posted) {
+                    msg_printf(NULL, MSG_USER_ERROR,
+                        "User idle time measurement failed because IOHIDGetParameter failed."
+                    );
+                    error_posted = true;
+                }
+                goto bail;
+            }
+            idleTime = ((double)params) / 1000.0 / 1000.0 / 1000.0;
+        } else {
+            // When the system first starts up, allow time for HIDSystem to be available if needed
+            if ((dtime() - init_time) > 180) {              // Limit retries to 180 seconds
+                
+                 msg_printf(NULL, MSG_USER_ERROR,
+                    "Could not connect to HIDSystem: user idle detection is disabled."
+                );
+                goto bail;
+            }
+            
+            service = IOServiceGetMatchingService(kIOMasterPortDefault, IOServiceMatching(kIOHIDSystemClass));
+            if (service == 0) goto bail;
+
+            kernResult = IOServiceOpen(service, mach_task_self(), kIOHIDParamConnectType, &gEventHandle);
+            if (kernResult != KERN_SUCCESS) goto bail;
+
+        }   // End gEventHandle == NULL
+    }       // End NXIdleTime API does not exist
+    
+ bail:   
     if (actual_idle_time) {
         *actual_idle_time = idleTime;
     }

lib/hostinfo.h

@@ -82,9 +82,16 @@ public:
 extern "C" {
 #endif
 #include <mach/port.h>
+#include <IOKit/hidsystem/IOHIDLib.h>
+#include <IOKit/hidsystem/IOHIDParameter.h>
+
+// Apple has removed NxIdleTime() beginning with OS 10.6, so we must use 
+// weak linking to avoid a run-time crash.  For details, please see the 
+// comments in the __APPLE__ version of HOST_INFO::users_idle() in 
+// client/hostinfo_unix.cpp.
 typedef mach_port_t NXEventHandle;
-NXEventHandle NXOpenEventStatus(void);
-extern double NXIdleTime(NXEventHandle handle);
+NXEventHandle NXOpenEventStatus(void) __attribute__((weak_import));
+extern double NXIdleTime(NXEventHandle handle) __attribute__((weak_import));
 #ifdef __cplusplus
 }	// extern "C"
 #endif