From 6463ea29564c872bd93278878a2e5245e7d02aa0 Mon Sep 17 00:00:00 2001
From: David Hunt <dhunt@iolanthe.attlocal.net>
Date: Mon, 13 Jul 2015 17:09:18 -0500
Subject: [PATCH] Fixed CPU updating

---
 darwin/DarwinProcessList.c | 25 ++++++++++++++++---------
 darwin/DarwinProcessList.h |  7 +++++--
 darwin/Platform.c          | 14 +++++++++-----
 3 files changed, 30 insertions(+), 16 deletions(-)

diff --git a/darwin/DarwinProcessList.c b/darwin/DarwinProcessList.c
index 1e9bd148..a58fae17 100644
--- a/darwin/DarwinProcessList.c
+++ b/darwin/DarwinProcessList.c
@@ -25,7 +25,8 @@ typedef struct DarwinProcessList_ {
    ProcessList super;
 
    host_basic_info_data_t host_info;
-   processor_cpu_load_info_t cpu_load;
+   processor_cpu_load_info_t prev_load;
+   processor_cpu_load_info_t curr_load;
 } DarwinProcessList;
 
 }*/
@@ -39,17 +40,21 @@ void ProcessList_getHostInfo(host_basic_info_data_t *p) {
    }
 }
 
-unsigned ProcessList_updateCPULoadInfo(processor_cpu_load_info_t *p) {
-   mach_msg_type_number_t info_size = sizeof(processor_cpu_load_info_t);
-   unsigned cpu_count;
-
-   if(NULL != p) {
+void ProcessList_freeCPULoadInfo(processor_cpu_load_info_t *p) {
+   if(NULL != p && NULL != *p) {
        if(0 != munmap(*p, vm_page_size)) {
            fprintf(stderr, "Unable to free old CPU load information\n");
            exit(8);
        }
    }
 
+   *p = NULL;
+}
+
+unsigned ProcessList_allocateCPULoadInfo(processor_cpu_load_info_t *p) {
+   mach_msg_type_number_t info_size = sizeof(processor_cpu_load_info_t);
+   unsigned cpu_count;
+
    if(0 != host_processor_info(mach_host_self(), PROCESSOR_CPU_LOAD_INFO, &cpu_count, (processor_info_array_t *)p, &info_size)) {
        fprintf(stderr, "Unable to retrieve CPU info\n");
        exit(4);
@@ -95,9 +100,9 @@ ProcessList* ProcessList_new(UsersTable* usersTable, Hashtable* pidWhiteList, ui
    ProcessList_init(&this->super, Class(Process), usersTable, pidWhiteList, userId);
    
    /* Initialize the previous information */
-   this->cpu_load = NULL;
-   this->super.cpuCount = ProcessList_updateCPULoadInfo(&this->cpu_load);
+   this->super.cpuCount = ProcessList_allocateCPULoadInfo(&this->prev_load);
    ProcessList_getHostInfo(&this->host_info);
+   ProcessList_allocateCPULoadInfo(&this->curr_load);
 
    return &this->super;
 }
@@ -118,7 +123,9 @@ void ProcessList_goThroughEntries(ProcessList* super) {
     gettimeofday(&tv, NULL); /* Start processing time */
 
     /* Update the global data (CPU times) */
-    ProcessList_updateCPULoadInfo(&dpl->cpu_load);
+    ProcessList_freeCPULoadInfo(&dpl->prev_load);
+    dpl->prev_load = dpl->curr_load;
+    ProcessList_allocateCPULoadInfo(&dpl->curr_load);
 
     /* We use kinfo_procs for initial data since :
      *
diff --git a/darwin/DarwinProcessList.h b/darwin/DarwinProcessList.h
index 065e8fbf..a893dcfe 100644
--- a/darwin/DarwinProcessList.h
+++ b/darwin/DarwinProcessList.h
@@ -16,13 +16,16 @@ typedef struct DarwinProcessList_ {
    ProcessList super;
 
    host_basic_info_data_t host_info;
-   processor_cpu_load_info_t cpu_load;
+   processor_cpu_load_info_t prev_load;
+   processor_cpu_load_info_t curr_load;
 } DarwinProcessList;
 
 
 void ProcessList_getHostInfo(host_basic_info_data_t *p);
 
-unsigned ProcessList_updateCPULoadInfo(processor_cpu_load_info_t *p);
+void ProcessList_freeCPULoadInfo(processor_cpu_load_info_t *p);
+
+unsigned ProcessList_allocateCPULoadInfo(processor_cpu_load_info_t *p);
 
 struct kinfo_proc *ProcessList_getKInfoProcs(size_t *count);
 
diff --git a/darwin/Platform.c b/darwin/Platform.c
index 1d43eaa8..b3af72fb 100644
--- a/darwin/Platform.c
+++ b/darwin/Platform.c
@@ -139,17 +139,21 @@ double Platform_setCPUValues(Meter* mtr, int cpu) {
     static const int CPU_METER_KERNEL = 2;
 
     DarwinProcessList *dpl = (DarwinProcessList *)mtr->pl;
-    processor_cpu_load_info_t ticks = &dpl->cpu_load[cpu-1];
+    processor_cpu_load_info_t prev = &dpl->prev_load[cpu-1];
+    processor_cpu_load_info_t curr = &dpl->curr_load[cpu-1];
     double total = 0;
 
     /* Take the sums */
     for(size_t i = 0; i < CPU_STATE_MAX; ++i) {
-        total += (double)ticks->cpu_ticks[i];
+        total += (double)curr->cpu_ticks[i] - (double)prev->cpu_ticks[i];
     }
 
-    mtr->values[CPU_METER_NICE] = (double)ticks->cpu_ticks[CPU_STATE_NICE] * 100.0 / total;
-    mtr->values[CPU_METER_NORMAL] = (double)ticks->cpu_ticks[CPU_STATE_USER] * 100.0 / total;
-    mtr->values[CPU_METER_KERNEL] = (double)ticks->cpu_ticks[CPU_STATE_SYSTEM] * 100.0 / total;
+    mtr->values[CPU_METER_NICE]
+            = ((double)curr->cpu_ticks[CPU_STATE_NICE] - (double)prev->cpu_ticks[CPU_STATE_NICE])* 100.0 / total;
+    mtr->values[CPU_METER_NORMAL]
+            = ((double)curr->cpu_ticks[CPU_STATE_USER] - (double)prev->cpu_ticks[CPU_STATE_USER])* 100.0 / total;
+    mtr->values[CPU_METER_KERNEL]
+            = ((double)curr->cpu_ticks[CPU_STATE_SYSTEM] - (double)prev->cpu_ticks[CPU_STATE_SYSTEM])* 100.0 / total;
 
     Meter_setItems(mtr, 3);