Adds a CPU Frequency meter to htop. After patching, run ./autogen.sh before configuring and compiling.

htop-1.0.2-cpufreq.patch

diff -rupN htop-1.0.2/CPUFreqMeter.c htop-1.0.2-new/CPUFreqMeter.c
--- htop-1.0.2/CPUFreqMeter.c	1969-12-31 21:00:00.000000000 -0300
+++ htop-1.0.2-new/CPUFreqMeter.c	2015-01-04 18:08:24.678220500 -0200
@@ -0,0 +1,115 @@
+/*
+htop - CPUFreqMeter.c
+(C) 2015 Vinicius Frederico
+Released under the GNU GPL, see the COPYING file
+in the source distribution for its full text.
+*/
+
+#include "CPUFreqMeter.h"
+
+#include "ProcessList.h"
+#include "CRT.h"
+
+#define _GNU_SOURCE
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <limits.h>
+
+/*{
+#include "Meter.h"
+}*/
+
+
+static void CPUFreqMeter_setValues(Meter* this, char* buffer, int lenBuffer) {
+  
+   FILE* fd = fopen(PROCDIR "/cpuinfo", "r");
+   if(fd == NULL) return 1;
+
+   size_t read, len;
+   char *line = NULL;
+   char *entry = NULL;
+   char *tstart = NULL, *tend = NULL;
+   int  cpufreq;
+
+   sprintf(buffer, "");
+   while ((read = getline(&line, &len, fd)) != -1) {
+      // this line contains cpu frequency
+      entry = strstr(line, "cpu MHz");
+      if (entry == NULL) continue;
+
+      // find the begin of the cpu frequency
+      tstart = strchr(entry, ':');
+      if (tstart == NULL) continue;
+      tstart += 2; // jump over the ": "
+
+      // find the end of the cpu frequency.
+      tend = strchr(tstart, '.'); // just the integer
+      if (tend == NULL) continue;
+
+      // convert the string into an integer, this is necessary for further steps
+      cpufreq = strtol(tstart, &tend, 10);
+      if (cpufreq == LONG_MAX || cpufreq == LONG_MIN) continue;
+      if (tstart == tend) continue;
+
+      sprintf(buffer, "%s%d MHz ", buffer, cpufreq);
+   }
+
+   free(line);
+   fclose(fd);
+}
+
+static void CPUFreqMeter_display(Object* cast, RichString* out) {
+   
+   FILE* fd = fopen(PROCDIR "/cpuinfo", "r");
+   if(fd == NULL) return 1;
+
+   int textColor   = CRT_colors[METER_TEXT];
+   int cpuFreqColor   = CRT_colors[METER_VALUE];
+   
+   size_t read, len;
+   char *line = NULL;
+   char *entry = NULL;
+   char *tstart = NULL, *tend = NULL;
+   int  cpufreq;
+   while ((read = getline(&line, &len, fd)) != -1) {
+      // this line contains cpu frequency
+      entry = strstr(line, "cpu MHz");
+      if (entry == NULL) continue;
+
+      // find the begin of the cpu frequency
+      tstart = strchr(entry, ':');
+      if (tstart == NULL) continue;
+      tstart += 2; // jump over the ": "
+
+      // find the end of the cpu frequency.
+      tend = strchr(tstart, '.'); // just the integer
+      if (tend == NULL) continue;
+
+      // convert the string into an integer, this is necessary for further steps
+      cpufreq = strtol(tstart, &tend, 10);
+      if (cpufreq == LONG_MAX || cpufreq == LONG_MIN) continue;
+      if (tstart == tend) continue;
+
+      // output the cpu frequency
+      char buffer[20];
+      sprintf(buffer, "%d", cpufreq);
+      RichString_append(out, cpuFreqColor, buffer);
+      RichString_append(out, textColor, " MHz ");
+   }
+
+   free(line);
+   fclose(fd);
+}
+
+MeterType CPUFreqMeter = {
+   .setValues = CPUFreqMeter_setValues,
+   .display = CPUFreqMeter_display,
+   .mode = TEXT_METERMODE,
+   .items = 1,
+   .total = 100.0,
+   .attributes = NULL,
+   .name = "CPUFrequency",
+   .uiName = "CPU Frequency",
+   .caption = "CPU Frequency: "
+};
diff -rupN htop-1.0.2/Header.c htop-1.0.2-new/Header.c
--- htop-1.0.2/Header.c	2011-12-26 19:52:26.000000000 -0200
+++ htop-1.0.2-new/Header.c	2015-01-04 18:08:24.678978900 -0200
@@ -14,6 +14,7 @@ in the source distribution for its full
 #include "TasksMeter.h"
 #include "LoadAverageMeter.h"
 #include "UptimeMeter.h"
+#include "CPUFreqMeter.h"
 #include "BatteryMeter.h"
 #include "ClockMeter.h"
 #include "HostnameMeter.h"
diff -rupN htop-1.0.2/Makefile.am htop-1.0.2-new/Makefile.am
--- htop-1.0.2/Makefile.am	2012-10-03 17:18:30.000000000 -0300
+++ htop-1.0.2-new/Makefile.am	2015-01-04 18:08:55.035839600 -0200
@@ -22,6 +22,8 @@ IOPriorityPanel.c SignalsPanel.c String.
 UptimeMeter.c UsersTable.c Vector.c AvailableColumnsPanel.c AffinityPanel.c \
 HostnameMeter.c OpenFilesScreen.c Affinity.c IOPriority.c
 
+myhtopsources += CPUFreqMeter.c
+
 myhtopheaders = AvailableColumnsPanel.h AvailableMetersPanel.h \
 CategoriesPanel.h CheckItem.h ClockMeter.h ColorsPanel.h ColumnsPanel.h \
 IOPriorityPanel.h CPUMeter.h CRT.h DisplayOptionsPanel.h FunctionBar.h \
@@ -31,6 +33,8 @@ ScreenManager.h Settings.h SignalsPanel.
 SwapMeter.h TasksMeter.h TraceScreen.h UptimeMeter.h UsersTable.h Vector.h \
 Process.h AffinityPanel.h HostnameMeter.h OpenFilesScreen.h Affinity.h IOPriority.h
 
+myhtopheaders += CPUFreqMeter.h
+
 SUFFIXES = .h
 
 BUILT_SOURCES = $(myhtopheaders)
diff -rupN htop-1.0.2/Meter.c htop-1.0.2-new/Meter.c
--- htop-1.0.2/Meter.c	2012-02-02 21:06:38.000000000 -0200
+++ htop-1.0.2-new/Meter.c	2015-01-04 18:08:24.680595200 -0200
@@ -13,6 +13,7 @@ in the source distribution for its full
 #include "TasksMeter.h"
 #include "LoadAverageMeter.h"
 #include "UptimeMeter.h"
+#include "CPUFreqMeter.h"
 #include "BatteryMeter.h"
 #include "ClockMeter.h"
 #include "HostnameMeter.h"
@@ -127,6 +128,7 @@ MeterType* Meter_types[] = {
    &SwapMeter,
    &TasksMeter,
    &UptimeMeter,
+   &CPUFreqMeter,
    &BatteryMeter,
    &HostnameMeter,
    &AllCPUsMeter,