Another mega-patch for the refactoring process.

Kinda runs, but functionality from the original main loop
is still missing. Patience.

19 files changed, 300 insertions, 240 deletions

diff --git a/Action.c b/Action.c
index b56f195a..f968fc4a 100644
--- a/Action.c
+++ b/Action.c
@@ -12,6 +12,7 @@ in the source distribution for its full text.
 #include "AffinityPanel.h"
 #include "CategoriesPanel.h"
 #include "CRT.h"
+#include "MainPanel.h"
 #include "OpenFilesScreen.h"
 #include "Process.h"
 #include "ScreenManager.h"
@@ -58,37 +59,8 @@ typedef struct State_ {
    Header* header;
 } State;
 
-typedef bool(*Action_ForeachProcessFn)(Process*, size_t);
-
 }*/
 
-int Action_selectedPid(Panel* panel) {
-   Process* p = (Process*) Panel_getSelected(panel);
-   if (p) {
-      return p->pid;
-   }
-   return -1;
-}
-
-bool Action_foreachProcess(Panel* panel, Action_ForeachProcessFn fn, int arg, bool* wasAnyTagged) {
-   bool ok = true;
-   bool anyTagged = false;
-   for (int i = 0; i < Panel_size(panel); i++) {
-      Process* p = (Process*) Panel_get(panel, i);
-      if (p->tag) {
-         ok = fn(p, arg) && ok;
-         anyTagged = true;
-      }
-   }
-   if (!anyTagged) {
-      Process* p = (Process*) Panel_getSelected(panel);
-      if (p) ok = fn(p, arg) && ok;
-   }
-   if (wasAnyTagged)
-      *wasAnyTagged = anyTagged;
-   return ok;
-}
-
 Object* Action_pickFromVector(State* st, Panel* list, int x, const char** keyLabels) {
    Panel* panel = st->panel;
    Header* header = st->header;
@@ -97,14 +69,14 @@ Object* Action_pickFromVector(State* st, Panel* list, int x, const char** keyLab
    int y = panel->y;
    const char* fuKeys[] = {"Enter", "Esc", NULL};
    int fuEvents[] = {13, 27};
-   ScreenManager* scr = ScreenManager_new(0, y, 0, -1, HORIZONTAL, header, settings, false);
+   ScreenManager* scr = ScreenManager_new(0, header->height, 0, -1, HORIZONTAL, header, settings, false);
    scr->allowFocusChange = false;
    ScreenManager_add(scr, list, FunctionBar_new(keyLabels, fuKeys, fuEvents), x - 1);
    ScreenManager_add(scr, panel, NULL, -1);
    Panel* panelFocus;
    int ch;
    bool unfollow = false;
-   int pid = Action_selectedPid(panel);
+   int pid = MainPanel_selectedPid((MainPanel*)panel);
    if (header->pl->following == -1) {
       header->pl->following = pid;
       unfollow = true;
@@ -141,9 +113,9 @@ static void Setup_run(Settings* settings, const Header* header, ProcessList* pl)
    ScreenManager_delete(scr);
 }
 
-static bool changePriority(Panel* panel, int delta) {
+static bool changePriority(MainPanel* panel, int delta) {
    bool anyTagged;
-   bool ok = Action_foreachProcess(panel, (Action_ForeachProcessFn) Process_changePriorityBy, delta, &anyTagged);
+   bool ok = MainPanel_foreachProcess(panel, (MainPanel_ForeachProcessFn) Process_changePriorityBy, delta, &anyTagged);
    if (!ok)
       beep();
    return anyTagged;
@@ -165,13 +137,6 @@ bool Action_setUserOnly(const char* userName, uid_t* userId) {
    return false;
 }
 
-static const char* getMainPanelValue(Panel* panel, int i) {
-   Process* p = (Process*) Panel_get(panel, i);
-   if (p)
-      return p->comm;
-   return "";
-}
-
 static void tagAllChildren(Panel* panel, Process* parent) {
    parent->tag = true;
    pid_t ppid = parent->pid;
@@ -266,12 +231,12 @@ static Htop_Reaction actionIncSearch(State* st) {
 }
 
 static Htop_Reaction actionHigherPriority(State* st) {
-   bool changed = changePriority(st->panel, -1);
+   bool changed = changePriority((MainPanel*)st->panel, -1);
    return changed ? HTOP_REFRESH : HTOP_OK;
 }
 
 static Htop_Reaction actionLowerPriority(State* st) {
-   bool changed = changePriority(st->panel, 1);
+   bool changed = changePriority((MainPanel*)st->panel, 1);
    return changed ? HTOP_REFRESH : HTOP_OK;
 }
 
@@ -314,7 +279,7 @@ static Htop_Reaction actionSetAffinity(State* st) {
    void* set = Action_pickFromVector(st, affinityPanel, 15, fuFunctions);
    if (set) {
       Affinity* affinity = AffinityPanel_getAffinity(affinityPanel, st->pl);
-      bool ok = Action_foreachProcess(panel, (Action_ForeachProcessFn) Affinity_set, (size_t) affinity, NULL);
+      bool ok = MainPanel_foreachProcess((MainPanel*)panel, (MainPanel_ForeachProcessFn) Affinity_set, (size_t) affinity, NULL);
       if (!ok) beep();
       Affinity_delete(affinity);
    }
@@ -332,7 +297,7 @@ static Htop_Reaction actionKill(State* st) {
          Panel_setHeader(st->panel, "Sending...");
          Panel_draw(st->panel, true);
          refresh();
-         Action_foreachProcess(st->panel, (Action_ForeachProcessFn) Process_sendSignal, (size_t) sgn->key, NULL);
+         MainPanel_foreachProcess((MainPanel*)st->panel, (MainPanel_ForeachProcessFn) Process_sendSignal, (size_t) sgn->key, NULL);
          napms(500);
       }
    }
@@ -361,7 +326,7 @@ static Htop_Reaction actionFilterByUser(State* st) {
 }
 
 static Htop_Reaction actionFollow(State* st) {
-   st->pl->following = Action_selectedPid(st->panel);
+   st->pl->following = MainPanel_selectedPid((MainPanel*)st->panel);
    return HTOP_KEEP_FOLLOWING;
 }
 
diff --git a/Action.h b/Action.h
index 0a1bf024..dd11fdb4 100644
--- a/Action.h
+++ b/Action.h
@@ -39,12 +39,6 @@ typedef struct State_ {
    Header* header;
 } State;
 
-typedef bool(*Action_ForeachProcessFn)(Process*, size_t);
-
-
-int Action_selectedPid(Panel* panel);
-
-bool Action_foreachProcess(Panel* panel, Action_ForeachProcessFn fn, int arg, bool* wasAnyTagged);
 
 Object* Action_pickFromVector(State* st, Panel* list, int x, const char** keyLabels);
 
diff --git a/BatteryMeter.c b/BatteryMeter.c
index 5cd0c389..d0dff92e 100644
--- a/BatteryMeter.c
+++ b/BatteryMeter.c
@@ -9,7 +9,7 @@ This meter written by Ian P. Hands (iphands@gmail.com, ihands@redhat.com).
 
 #include "BatteryMeter.h"
 
-#include "Platform.h"
+#include "Battery.h"
 #include "ProcessList.h"
 #include "CRT.h"
 #include "String.h"
@@ -35,7 +35,7 @@ static void BatteryMeter_setValues(Meter * this, char *buffer, int len) {
    ACPresence isOnAC;
    double percent;
    
-   Platform_getBatteryLevel(&percent, &isOnAC);
+   Battery_getData(&percent, &isOnAC);
 
    if (percent == -1) {
       this->values[0] = 0;
diff --git a/CategoriesPanel.c b/CategoriesPanel.c
index cbad064d..d691d7f4 100644
--- a/CategoriesPanel.c
+++ b/CategoriesPanel.c
@@ -111,7 +111,6 @@ static HandlerResult CategoriesPanel_eventHandler(Panel* super, int ch) {
             result = IGNORED;
          break;
    }
-
    if (result == HANDLED) {
       int size = ScreenManager_size(this->scr);
       for (int i = 1; i < size; i++)
@@ -131,7 +130,6 @@ static HandlerResult CategoriesPanel_eventHandler(Panel* super, int ch) {
             break;
       }
    }
-
    return result;
 }
 
diff --git a/Header.c b/Header.c
index 8b7cef6d..6e99a681 100644
--- a/Header.c
+++ b/Header.c
@@ -18,15 +18,16 @@ in the source distribution for its full text.
 
 /*{
 #include "Meter.h"
+#include "Settings.h"
 #include "Vector.h"
 
 typedef struct Header_ {
    Vector** columns;
+   Settings* settings;
    struct ProcessList_* pl;
-   int height;
-   int pad;
    int nrColumns;
-   bool margin;
+   int pad;
+   int height;
 } Header;
 
 }*/
@@ -39,15 +40,15 @@ typedef struct Header_ {
 #define Header_forEachColumn(this_, i_) for (int i_=0; i_ < this->nrColumns; i_++)
 #endif
 
-Header* Header_new(struct ProcessList_* pl, int nrColumns) {
+Header* Header_new(struct ProcessList_* pl, Settings* settings, int nrColumns) {
    Header* this = calloc(1, sizeof(Header));
    this->columns = calloc(nrColumns, sizeof(Vector*));
+   this->settings = settings;
+   this->pl = pl;
    this->nrColumns = nrColumns;
    Header_forEachColumn(this, i) {
       this->columns[i] = Vector_new(Class(Meter), true, DEFAULT_SIZE);
    }
-   this->margin = true;
-   this->pl = pl;
    return this;
 }
 
@@ -59,6 +60,17 @@ void Header_delete(Header* this) {
    free(this);
 }
 
+void Header_populateFromSettings(Header* this) {
+   Header_forEachColumn(this, col) {
+      MeterColumnSettings* colSettings = &this->settings->columns[col];
+      for (int i = 0; i < colSettings->len; i++) {
+         Header_addMeterByName(this, colSettings->names[i], col);
+         Header_setMode(this, i, colSettings->modes[i], col);
+      }
+   }
+   Header_calculateHeight(this);
+}
+
 MeterModeId Header_addMeterByName(Header* this, char* name, int column) {
    Vector* meters = this->columns[column];
 
@@ -157,7 +169,7 @@ void Header_draw(const Header* this) {
 }
 
 int Header_calculateHeight(Header* this) {
-   int pad = this->margin ? 2 : 0;
+   int pad = this->settings->headerMargin ? 2 : 0;
    int maxHeight = pad;
 
    Header_forEachColumn(this, col) {
@@ -170,5 +182,6 @@ int Header_calculateHeight(Header* this) {
       maxHeight = MAX(maxHeight, height);
    }
    this->height = maxHeight;
+   this->pad = pad;
    return maxHeight;
 }
diff --git a/Header.h b/Header.h
index 11c04960..13811a9e 100644
--- a/Header.h
+++ b/Header.h
@@ -10,15 +10,16 @@ in the source distribution for its full text.
 */
 
 #include "Meter.h"
+#include "Settings.h"
 #include "Vector.h"
 
 typedef struct Header_ {
    Vector** columns;
+   Settings* settings;
    struct ProcessList_* pl;
-   int height;
-   int pad;
    int nrColumns;
-   bool margin;
+   int pad;
+   int height;
 } Header;
 
 
@@ -30,10 +31,12 @@ typedef struct Header_ {
 #define Header_forEachColumn(this_, i_) for (int i_=0; i_ < this->nrColumns; i_++)
 #endif
 
-Header* Header_new(struct ProcessList_* pl, int nrColumns);
+Header* Header_new(struct ProcessList_* pl, Settings* settings, int nrColumns);
 
 void Header_delete(Header* this);
 
+void Header_populateFromSettings(Header* this);
+
 MeterModeId Header_addMeterByName(Header* this, char* name, int column);
 
 void Header_setMode(Header* this, int i, MeterModeId mode, int column);
diff --git a/Meter.c b/Meter.c
index 1d4e6e3b..b1083cf0 100644
--- a/Meter.c
+++ b/Meter.c
@@ -23,6 +23,8 @@ in the source distribution for its full text.
 
 #define METER_BUFFER_LEN 256
 
+#define GRAPH_DELAY (DEFAULT_DELAY/2)
+
 /*{
 #include "ListItem.h"
 
@@ -342,7 +344,7 @@ static void GraphMeterMode_draw(Meter* this, int x, int y, int w) {
    struct timeval now;
    gettimeofday(&now, NULL);
    if (!timercmp(&now, &(data->time), <)) {
-      struct timeval delay = { .tv_sec = (int)(DEFAULT_DELAY/10), .tv_usec = (DEFAULT_DELAY-((int)(DEFAULT_DELAY/10)*10)) * 100000 };
+      struct timeval delay = { .tv_sec = (int)(GRAPH_DELAY/10), .tv_usec = (GRAPH_DELAY-((int)(GRAPH_DELAY/10)*10)) * 100000 };
       timeradd(&now, &delay, &(data->time));
 
       for (int i = 0; i < nValues - 1; i++)
diff --git a/Meter.h b/Meter.h
index 97efc1ad..67df33b2 100644
--- a/Meter.h
+++ b/Meter.h
@@ -11,6 +11,8 @@ in the source distribution for its full text.
 
 #define METER_BUFFER_LEN 256
 
+#define GRAPH_DELAY (DEFAULT_DELAY/2)
+
 #include "ListItem.h"
 
 #include <sys/time.h>
diff --git a/Panel.c b/Panel.c
index 8982cc2e..de120d7c 100644
--- a/Panel.c
+++ b/Panel.c
@@ -28,11 +28,11 @@ in the source distribution for its full text.
 typedef struct Panel_ Panel;
 
 typedef enum HandlerResult_ {
-   HANDLED     = 0x00,
-   IGNORED     = 0x01,
-   BREAK_LOOP  = 0x02,
-   REFRESH     = 0x04,
-   RECALCULATE = 0x08,
+   HANDLED     = 0x01,
+   IGNORED     = 0x02,
+   BREAK_LOOP  = 0x04,
+   REFRESH     = 0x08,
+   RECALCULATE = 0x10,
 } HandlerResult;
 
 #define EVENT_SETSELECTED -1
diff --git a/Panel.h b/Panel.h
index 717f6dde..baac7016 100644
--- a/Panel.h
+++ b/Panel.h
@@ -17,11 +17,11 @@ in the source distribution for its full text.
 typedef struct Panel_ Panel;
 
 typedef enum HandlerResult_ {
-   HANDLED     = 0x00,
-   IGNORED     = 0x01,
-   BREAK_LOOP  = 0x02,
-   REFRESH     = 0x04,
-   RECALCULATE = 0x08,
+   HANDLED     = 0x01,
+   IGNORED     = 0x02,
+   BREAK_LOOP  = 0x04,
+   REFRESH     = 0x08,
+   RECALCULATE = 0x10,
 } HandlerResult;
 
 #define EVENT_SETSELECTED -1
diff --git a/ScreenManager.c b/ScreenManager.c
index aad1b024..d7353b79 100644
--- a/ScreenManager.c
+++ b/ScreenManager.c
@@ -81,10 +81,11 @@ void ScreenManager_add(ScreenManager* this, Panel* item, FunctionBar* fuBar, int
          Panel* last = (Panel*) Vector_get(this->panels, this->panelCount - 1);
          lastX = last->x + last->w + 1;
       }
+      int height = LINES - this->y1 + this->y2;
       if (size > 0) {
-         Panel_resize(item, size, LINES-this->y1+this->y2);
+         Panel_resize(item, size, height);
       } else {
-         Panel_resize(item, COLS-this->x1+this->x2-lastX, LINES-this->y1+this->y2);
+         Panel_resize(item, COLS-this->x1+this->x2-lastX, height);
       }
       Panel_move(item, lastX, this->y1);
    }
@@ -114,16 +115,19 @@ void ScreenManager_resize(ScreenManager* this, int x1, int y1, int x2, int y2) {
    this->x2 = x2;
    this->y2 = y2;
    int panels = this->panelCount;
-   int lastX = 0;
-   for (int i = 0; i < panels - 1; i++) {
-      Panel* panel = (Panel*) Vector_get(this->panels, i);
-      Panel_resize(panel, panel->w, LINES-y1+y2);
+   if (this->orientation == HORIZONTAL) {
+      int lastX = 0;
+      for (int i = 0; i < panels - 1; i++) {
+         Panel* panel = (Panel*) Vector_get(this->panels, i);
+         Panel_resize(panel, panel->w, LINES-y1+y2);
+         Panel_move(panel, lastX, y1);
+         lastX = panel->x + panel->w + 1;
+      }
+      Panel* panel = (Panel*) Vector_get(this->panels, panels-1);
+      Panel_resize(panel, COLS-x1+x2-lastX, LINES-y1+y2);
       Panel_move(panel, lastX, y1);
-      lastX = panel->x + panel->w + 1;
    }
-   Panel* panel = (Panel*) Vector_get(this->panels, panels-1);
-   Panel_resize(panel, COLS-x1+x2-lastX, LINES-y1+y2);
-   Panel_move(panel, lastX, y1);
+   // TODO: VERTICAL
 }
 
 void ScreenManager_run(ScreenManager* this, Panel** lastFocus, int* lastKey) {
@@ -154,25 +158,29 @@ void ScreenManager_run(ScreenManager* this, Panel** lastFocus, int* lastKey) {
          double newTime = ((double)tv.tv_sec * 10) + ((double)tv.tv_usec / 100000);
          timeToRecalculate = (newTime - oldTime > this->settings->delay);
          if (newTime < oldTime) timeToRecalculate = true; // clock was adjusted?
-
-         if (timeToRecalculate) {
-            Header_draw(this->header);
-            oldTime = newTime;
-         }
-
+//fprintf(stderr, "\n%p %f ", this, newTime);
          if (doRefresh) {
             if (timeToRecalculate || forceRecalculate) {
                ProcessList_scan(this->header->pl);
-               forceRecalculate = false;
+//fprintf(stderr, "scan ");
             }
+//fprintf(stderr, "sortTo=%d ", sortTimeout);
             if (sortTimeout == 0 || this->settings->treeView) {
                ProcessList_sort(this->header->pl);
+//fprintf(stderr, "sort ");
                sortTimeout = 1;
             }
             //this->header->pl->incFilter = IncSet_filter(inc);
             ProcessList_rebuildPanel(this->header->pl);
+//fprintf(stderr, "rebuild ");
             drawPanel = true;
          }
+         if (timeToRecalculate || forceRecalculate) {
+            Header_draw(this->header);
+//fprintf(stderr, "drawHeader ");
+            oldTime = newTime;
+            forceRecalculate = false;
+         }
          doRefresh = true;
       }
       
@@ -180,6 +188,7 @@ void ScreenManager_run(ScreenManager* this, Panel** lastFocus, int* lastKey) {
          for (int i = 0; i < panels; i++) {
             Panel* panel = (Panel*) Vector_get(this->panels, i);
             Panel_draw(panel, i == focus);
+//fprintf(stderr, "drawPanel ");
             if (i < panels) {
                if (this->orientation == HORIZONTAL) {
                   mvvline(panel->y, panel->x+panel->w, ' ', panel->h+1);
@@ -196,6 +205,8 @@ void ScreenManager_run(ScreenManager* this, Panel** lastFocus, int* lastKey) {
 
       int prevCh = ch;
       ch = getch();
+
+//fprintf(stderr, "ch=%d ", ch);
       
       if (ch == KEY_MOUSE) {
          MEVENT mevent;
@@ -218,9 +229,9 @@ void ScreenManager_run(ScreenManager* this, Panel** lastFocus, int* lastKey) {
             }
          }
       }
-      
       if (Panel_eventHandlerFn(panelFocus)) {
          HandlerResult result = Panel_eventHandler(panelFocus, ch);
+//fprintf(stderr, "eventResult=%d ", result);
          if (result & REFRESH) {
             doRefresh = true;
             sortTimeout = 0;
@@ -230,14 +241,15 @@ void ScreenManager_run(ScreenManager* this, Panel** lastFocus, int* lastKey) {
             sortTimeout = 0;
          }
          if (result & HANDLED) {
+            drawPanel = true;
             continue;
          } else if (result & BREAK_LOOP) {
             quit = true;
             continue;
          }
       }
-      
       if (ch == ERR) {
+         sortTimeout--;
          if (prevCh == ch && !timeToRecalculate) {
             closeTimeout++;
             if (closeTimeout == 100) {
@@ -246,6 +258,7 @@ void ScreenManager_run(ScreenManager* this, Panel** lastFocus, int* lastKey) {
          } else
             closeTimeout = 0;
          drawPanel = false;
+//fprintf(stderr, "err ");
          continue;
       }
       drawPanel = true;
@@ -285,9 +298,12 @@ void ScreenManager_run(ScreenManager* this, Panel** lastFocus, int* lastKey) {
          quit = true;
          continue;
       default:
+//fprintf(stderr, "onKey ");
+         sortTimeout = resetSortTimeout;
          Panel_onKey(panelFocus, ch);
          break;
       }
+//fprintf(stderr, "loop ");
    }
 
    if (lastFocus)
diff --git a/Settings.c b/Settings.c
index e78f9918..8f2db0e8 100644
--- a/Settings.c
+++ b/Settings.c
@@ -26,7 +26,7 @@ typedef struct {
    char** names;
    int* modes;
 } MeterColumnSettings;
-   
+
 typedef struct Settings_ {
    char* filename;
    
diff --git a/Settings.h b/Settings.h
index 2ac431f0..af1fefb9 100644
--- a/Settings.h
+++ b/Settings.h
@@ -19,7 +19,7 @@ typedef struct {
    char** names;
    int* modes;
 } MeterColumnSettings;
-   
+
 typedef struct Settings_ {
    char* filename;
    
diff --git a/TasksMeter.c b/TasksMeter.c
index adcc55d9..7a3e5a47 100644
--- a/TasksMeter.c
+++ b/TasksMeter.c
@@ -20,7 +20,10 @@ int TasksMeter_attributes[] = {
 
 static void TasksMeter_setValues(Meter* this, char* buffer, int len) {
    Platform_setTasksValues(this);
-   snprintf(buffer, len, "%d/%d", (int) this->values[0], (int) this->total);
+   if (this->pl->settings->hideKernelThreads) {
+      this->values[0] = 0;
+   }
+   snprintf(buffer, len, "%d/%d", (int) this->values[3], (int) this->total);
 }
 
 static void TasksMeter_display(Object* cast, RichString* out) {
diff --git a/htop.c b/htop.c
index bb948b80..ef3182de 100644
--- a/htop.c
+++ b/htop.c
@@ -188,10 +188,13 @@ int main(int argc, char** argv) {
    UsersTable* ut = UsersTable_new();
    ProcessList* pl = ProcessList_new(ut, flags.pidWhiteList, flags.userId);
    
-   Header* header = Header_new(pl, 2);
    Settings* settings = Settings_new(pl->cpuCount);
    pl->settings = settings;
 
+   Header* header = Header_new(pl, settings, 2);
+
+   Header_populateFromSettings(header);
+
    if (flags.delay != -1)
       settings->delay = flags.delay;
    if (!flags.useColors) 
@@ -225,8 +228,8 @@ int main(int argc, char** argv) {
    };
    MainPanel_setState(panel, &state);
    
-   ScreenManager* scr = ScreenManager_new(0, 0, 0, -1, HORIZONTAL, header, settings, true);
-   ScreenManager_add(scr, (Panel*) panel, defaultBar, 0);
+   ScreenManager* scr = ScreenManager_new(0, header->height, 0, -1, HORIZONTAL, header, settings, true);
+   ScreenManager_add(scr, (Panel*) panel, defaultBar, -1);
 
    ProcessList_scan(pl);
    millisleep(75);
@@ -265,7 +268,7 @@ int main(int argc, char** argv) {
       double newTime = ((double)tv.tv_sec * 10) + ((double)tv.tv_usec / 100000);
       bool timeToRecalculate = (newTime - oldTime > settings->delay);
       if (newTime < oldTime) timeToRecalculate = true; // clock was adjusted?
-      int following = follow ? Action_selectedPid(panel) : -1;
+      int following = follow ? MainPanel_selectedPid((MainPanel*)panel) : -1;
       if (timeToRecalculate) {
          Header_draw(header);
          oldTime = newTime;
diff --git a/linux/Battery.c b/linux/Battery.c
index eb458af8..f766098f 100644
--- a/linux/Battery.c
+++ b/linux/Battery.c
@@ -11,28 +11,24 @@ Linux battery readings written by Ian P. Hands (iphands@gmail.com, ihands@redhat
 #define _GNU_SOURCE
 #endif
 #include <dirent.h>
+#include <errno.h>
 #include <unistd.h>
 #include <stdlib.h>
 #include <string.h>
+#include <fcntl.h>
+#include <time.h>
 #include "BatteryMeter.h"
 #include "String.h"
 
-static unsigned long int parseUevent(FILE * file, const char *key) {
-   char line[100];
-   unsigned long int dValue = 0;
-   char* saveptr;
-
-   while (fgets(line, sizeof line, file)) {
-      if (strncmp(line, key, strlen(key)) == 0) {
-         char *value;
-         strtok_r(line, "=", &saveptr);
-         value = strtok_r(NULL, "=", &saveptr);
-         dValue = atoi(value);
-         break;
-      }
-   }
-   return dValue;
-}
+#define SYS_POWERSUPPLY_DIR "/sys/class/power_supply"
+
+// ----------------------------------------
+// READ FROM /proc
+// ----------------------------------------
+
+// This implementation reading from from /proc/acpi is really inefficient,
+// but I think this is on the way out so I did not rewrite it.
+// The /sys implementation below does things the right way.
 
 static unsigned long int parseBatInfo(const char *fileName, const unsigned short int lineNum, const unsigned short int wordNum) {
    const char batteryPath[] = PROCDIR "/acpi/battery/";
@@ -94,15 +90,15 @@ static unsigned long int parseBatInfo(const char *fileName, const unsigned short
 static ACPresence procAcpiCheck() {
    ACPresence isOn = AC_ERROR;
    const char *power_supplyPath = PROCDIR "/acpi/ac_adapter";
-   DIR *power_supplyDir = opendir(power_supplyPath);
-   if (!power_supplyDir) {
+   DIR *dir = opendir(power_supplyPath);
+   if (!dir) {
       return AC_ERROR;
    }
 
    struct dirent result;
    struct dirent* dirEntry;
    for (;;) {
-      int err = readdir_r((DIR *) power_supplyDir, &result, &dirEntry);
+      int err = readdir_r((DIR *) dir, &result, &dirEntry);
       if (err || !dirEntry)
          break;
 
@@ -139,62 +135,12 @@ static ACPresence procAcpiCheck() {
       }
    }
 
-   if (power_supplyDir)
-      closedir(power_supplyDir);
-   return isOn;
-}
-
-static ACPresence sysCheck() {
-   ACPresence isOn = AC_ERROR;
-   const char *power_supplyPath = "/sys/class/power_supply";
-   DIR *power_supplyDir = opendir(power_supplyPath);
-   if (!power_supplyDir) {
-      return AC_ERROR;
-   }
-
-   struct dirent result;
-   struct dirent* dirEntry;
-   for (;;) {
-      int err = readdir_r((DIR *) power_supplyDir, &result, &dirEntry);
-      if (err || !dirEntry)
-         break;
-
-      char* entryName = (char *) dirEntry->d_name;
-      if (strncmp(entryName, "A", 1)) {
-         continue;
-      }
-      char onlinePath[50];
-      snprintf((char *) onlinePath, sizeof onlinePath, "%s/%s/online", power_supplyPath, entryName);
-      FILE* file = fopen(onlinePath, "r");
-      if (!file) {
-         isOn = AC_ERROR;
-      } else {
-         isOn = (fgetc(file) - '0');
-         fclose(file);
-         if (isOn == AC_PRESENT) {
-            // If any AC adapter is being used then stop
-            break;
-         }
-      }
-   }
-
-   if (power_supplyDir)
-      closedir(power_supplyDir);
-
+   if (dir)
+      closedir(dir);
    return isOn;
 }
 
-ACPresence Battery_isOnAC() {
-   if (access(PROCDIR "/acpi/ac_adapter", F_OK) == 0) {
-      return procAcpiCheck();
-   } else if (access("/sys/class/power_supply", F_OK) == 0) {
-      return sysCheck();
-   } else {
-      return AC_ERROR;
-   }
-}
-
-double Battery_getProcBatData() {
+static double Battery_getProcBatData() {
    const unsigned long int totalFull = parseBatInfo("info", 3, 4);
    if (totalFull == 0)
       return 0;
@@ -206,11 +152,58 @@ double Battery_getProcBatData() {
    return totalRemain * 100.0 / (double) totalFull;
 }
 
-double Battery_getSysBatData() {
-   const char *power_supplyPath = "/sys/class/power_supply/";
-   DIR *power_supplyDir = opendir(power_supplyPath);
-   if (!power_supplyDir)
-      return 0;
+static void Battery_getProcData(double* level, ACPresence* isOnAC) {
+   *level = Battery_getProcBatData();
+   *isOnAC = procAcpiCheck();
+}
+
+// ----------------------------------------
+// READ FROM /sys
+// ----------------------------------------
+
+static inline ssize_t xread(int fd, void *buf, size_t count) {
+  // Read some bytes. Retry on EINTR and when we don't get as many bytes as we requested.
+  size_t alreadyRead = 0;
+  for(;;) {
+     ssize_t res = read(fd, buf, count);
+     if (res == -1 && errno == EINTR) continue;
+     if (res > 0) {
+       buf = ((char*)buf)+res;
+       count -= res;
+       alreadyRead += res;
+     }
+     if (res == -1) return -1;
+     if (count == 0 || res == 0) return alreadyRead;
+  }
+}
+
+/**
+ * Returns a pointer to the suffix of `str` if its beginning matches `prefix`.
+ * Returns NULL if the prefix does not match.
+ * Examples: 
+ * match("hello world", "hello "); -> "world"
+ * match("hello world", "goodbye "); -> NULL
+ */
+static inline const char* match(const char* str, const char* prefix) {
+   for (;;) {
+      if (*prefix == '\0') {
+         return str;
+      }
+      if (*prefix != *str) {
+         return NULL;
+      }
+      prefix++; str++;
+   }
+}
+
+static void Battery_getSysData(double* level, ACPresence* isOnAC) {
+      
+   *level = 0;
+   *isOnAC = AC_ERROR;
+
+   DIR *dir = opendir(SYS_POWERSUPPLY_DIR);
+   if (!dir)
+      return;
 
    unsigned long int totalFull = 0;
    unsigned long int totalRemain = 0;
@@ -218,52 +211,120 @@ double Battery_getSysBatData() {
    struct dirent result;
    struct dirent* dirEntry;
    for (;;) {
-      int err = readdir_r((DIR *) power_supplyDir, &result, &dirEntry);
+      int err = readdir_r((DIR *) dir, &result, &dirEntry);
       if (err || !dirEntry)
          break;
       char* entryName = (char *) dirEntry->d_name;
-
-      if (strncmp(entryName, "BAT", 3)) {
-         continue;
+      const char filePath[50];
+
+      if (entryName[0] == 'B' && entryName[1] == 'A' && entryName[2] == 'T') {
+         
+         snprintf((char *) filePath, sizeof filePath, SYS_POWERSUPPLY_DIR "/%s/uevent", entryName);
+         int fd = open(filePath, O_RDONLY);
+         if (fd == -1) {
+            closedir(dir);
+            return;
+         }
+         char buffer[1024];
+         ssize_t buflen = xread(fd, buffer, 1023);
+         close(fd);
+         if (buflen < 1) {
+            closedir(dir);
+            return;
+         }
+         buffer[buflen] = '\0';
+         char *buf = buffer;
+         char *line = NULL;
+         bool full = false;
+         bool now = false;
+         while ((line = strsep(&buf, "\n")) != NULL) {
+            const char* ps = match(line, "POWER_SUPPLY_");
+            if (!ps) {
+               continue;
+            }
+            const char* energy = match(ps, "ENERGY_");
+            if (!energy) {
+               energy = match(ps, "CHARGE_");
+            }
+            if (!energy) {
+               continue;
+            }
+            const char* value = (!full) ? match(energy, "FULL=") : NULL;
+            if (value) {
+               totalFull += atoi(value);
+               full = true;
+               if (now) break;
+               continue;
+            }
+            value = (!now) ? match(energy, "NOW=") : NULL;
+            if (value) {
+               totalRemain += atoi(value);
+               now = true;
+               if (full) break;
+               continue;
+            }
+         }
+      } else if (entryName[0] == 'A') {
+         if (*isOnAC != AC_ERROR) {
+            continue;
+         }
+      
+         snprintf((char *) filePath, sizeof filePath, SYS_POWERSUPPLY_DIR "/%s/online", entryName);
+         int fd = open(filePath, O_RDONLY);
+         if (fd == -1) {
+            closedir(dir);
+            return;
+         }
+         char buffer[2] = "";
+         for(;;) {
+            ssize_t res = read(fd, buffer, 1);
+            if (res == -1 && errno == EINTR) continue;
+            break;
+         }
+         close(fd);
+         if (buffer[0] == '0') {
+            *isOnAC = AC_ABSENT;
+         } else if (buffer[0] == '1') {
+            *isOnAC = AC_PRESENT;
+         }
       }
+   }
+   closedir(dir);
+   *level = totalFull > 0 ? ((double) totalRemain * 100) / (double) totalFull : 0;
+}
 
-      const char ueventPath[50];
+static enum { BAT_PROC, BAT_SYS, BAT_ERR } Battery_method = BAT_PROC;
 
-      snprintf((char *) ueventPath, sizeof ueventPath, "%s%s/uevent", power_supplyPath, entryName);
+static time_t Battery_cacheTime = 0;
+static double Battery_cacheLevel = 0;
+static ACPresence Battery_cacheIsOnAC = 0;
 
-      FILE *file;
-      if ((file = fopen(ueventPath, "r")) == NULL) {
-         closedir(power_supplyDir);
-         return 0;
-      }
+void Battery_getData(double* level, ACPresence* isOnAC) {
+   time_t now = time(NULL);
+   // update battery reading is slow. Update it each 10 seconds only.
+   if (now < Battery_cacheTime + 10) {
+      *level = Battery_cacheLevel;
+      *isOnAC = Battery_cacheIsOnAC;
+      return;
+   }
 
-      if ((totalFull += parseUevent(file, "POWER_SUPPLY_ENERGY_FULL="))) {
-         totalRemain += parseUevent(file, "POWER_SUPPLY_ENERGY_NOW=");
-      } else {
-         //reset file pointer
-         if (fseek(file, 0, SEEK_SET) < 0) {
-            closedir(power_supplyDir);
-            fclose(file);
-            return 0;
-         }
+   if (Battery_method == BAT_PROC) {
+      Battery_getProcData(level, isOnAC);
+      if (*level == 0) {
+         Battery_method = BAT_SYS;
       }
-
-      //Some systems have it as CHARGE instead of ENERGY.
-      if ((totalFull += parseUevent(file, "POWER_SUPPLY_CHARGE_FULL="))) {
-         totalRemain += parseUevent(file, "POWER_SUPPLY_CHARGE_NOW=");
-      } else {
-        //reset file pointer
-         if (fseek(file, 0, SEEK_SET) < 0) {
-            closedir(power_supplyDir);
-            fclose(file);
-            return 0;
-         }
+   }
+   if (Battery_method == BAT_SYS) {
+      Battery_getSysData(level, isOnAC);
+      if (*level == 0) {
+         Battery_method = BAT_ERR;
       }
-
-      fclose(file);
    }
-
-   const double percent = totalFull > 0 ? ((double) totalRemain * 100) / (double) totalFull : 0;
-   closedir(power_supplyDir);
-   return percent;
+   if (Battery_method == BAT_ERR) {
+      *level = -1;
+      *isOnAC = AC_ERROR;
+   }
+   Battery_cacheLevel = *level;
+   Battery_cacheIsOnAC = *isOnAC;
+   Battery_cacheTime = now;
 }
diff --git a/linux/Battery.h b/linux/Battery.h
index 88ba2b01..4cb22a89 100644
--- a/linux/Battery.h
+++ b/linux/Battery.h
@@ -15,10 +15,27 @@ Linux battery readings written by Ian P. Hands (iphands@gmail.com, ihands@redhat
 #define _GNU_SOURCE
 #endif
 
-ACPresence Battery_isOnAC();
+#define SYS_POWERSUPPLY_DIR "/sys/class/power_supply"
 
-double Battery_getProcBatData();
+// ----------------------------------------
+// READ FROM /proc
+// ----------------------------------------
 
-double Battery_getSysBatData();
+// This implementation reading from from /proc/acpi is really inefficient,
+// but I think this is on the way out so I did not rewrite it.
+// The /sys implementation below does things the right way.
+
+// ----------------------------------------
+// READ FROM /sys
+// ----------------------------------------
+
+/**
+ * Returns a pointer to the suffix of `str` if its beginning matches `prefix`.
+ * Returns NULL if the prefix does not match.
+ * Examples: 
+ * match("hello world", "hello "); -> "world"
+ * match("hello world", "goodbye "); -> NULL
+ */
+void Battery_getData(double* level, ACPresence* isOnAC);
 
 #endif
diff --git a/linux/Platform.c b/linux/Platform.c
index a5704d23..0a763362 100644
--- a/linux/Platform.c
+++ b/linux/Platform.c
@@ -27,6 +27,7 @@ in the source distribution for its full text.
 
 /*{
 #include "Action.h"
+#include "MainPanel.h"
 #include "BatteryMeter.h"
 }*/
 
@@ -41,7 +42,7 @@ static Htop_Reaction Platform_actionSetIOPriority(State* st) {
    void* set = Action_pickFromVector(st, ioprioPanel, 21, fuFunctions);
    if (set) {
       IOPriority ioprio = IOPriorityPanel_getIOPriority(ioprioPanel);
-      bool ok = Action_foreachProcess(panel, (Action_ForeachProcessFn) LinuxProcess_setIOPriority, (size_t) ioprio, NULL);
+      bool ok = MainPanel_foreachProcess((MainPanel*)panel, (MainPanel_ForeachProcessFn) LinuxProcess_setIOPriority, (size_t) ioprio, NULL);
       if (!ok)
          beep();
    }
@@ -106,23 +107,6 @@ int Platform_getMaxPid() {
    return maxPid;
 }
 
-void Platform_getBatteryLevel(double* level, ACPresence* isOnAC) {
-
-   double percent = Battery_getProcBatData();
-
-   if (percent == 0) {
-      percent = Battery_getSysBatData();
-      if (percent == 0) {
-         *level = -1;
-         *isOnAC = AC_ERROR;
-         return;
-      }
-   }
-
-   *isOnAC = Battery_isOnAC();
-   *level = percent;
-}
-
 double Platform_setCPUValues(Meter* this, int cpu) {
    LinuxProcessList* pl = (LinuxProcessList*) this->pl;
    CPUData* cpuData = &(pl->cpus[cpu]);
diff --git a/linux/Platform.h b/linux/Platform.h
index 6fb6b543..c4a5cd24 100644
--- a/linux/Platform.h
+++ b/linux/Platform.h
@@ -10,6 +10,7 @@ in the source distribution for its full text.
 */
 
 #include "Action.h"
+#include "MainPanel.h"
 #include "BatteryMeter.h"
 
 void Platform_setBindings(Htop_Action* keys);
@@ -22,8 +23,6 @@ void Platform_getLoadAverage(double* one, double* five, double* fifteen);
 
 int Platform_getMaxPid();
 
-void Platform_getBatteryLevel(double* level, ACPresence* isOnAC);
-
 double Platform_setCPUValues(Meter* this, int cpu);
 
 void Platform_setMemoryValues(Meter* this);