source: npl/mediabox/lcdproc_edwin/src/clients/lcdproc/batt.c

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/utsname.h>

#include "../../shared/sockets.h"

#include "main.h"
#include "mode.h"
#include "batt.h"

int batt_fd = 0;


static int get_batt_stat(int *acstat, int *battstat,
                         int *battflag, int *percent);

static int get_batt_stat(int *acstat, int *battstat,
                         int *battflag, int *percent)
{
  char str[64];
  
  if(!batt_fd)
    batt_fd = open("/proc/apm", O_RDONLY);
  if(batt_fd <= 0) return -1;

  if(lseek(batt_fd, 0, 0) != 0) return -1;

  if(read(batt_fd, str, sizeof(str)-1) < 0) return -1;
  
  if(3 > sscanf(str+13, "0x%x 0x%x 0x%x %d",
                acstat, battstat, battflag, percent))
    return -1;

  return 0;
  
}



int batt_init()
{
   static int first = 1;

   if(first)
   {
      first = 0;
      sock_send_string(sock, "screen_add B\n");
   }

   return 0;
}

int batt_close()
{
   if(batt_fd) close(batt_fd);
   batt_fd = 0;

   return 0;
}


////////////////////////////////////////////////////////////////////////
// Battery Screen shows apm battery status...
//

//####################
//## Battery: 100% ###
//AC: Unknown
//Batt: Low (Charging)
//E------------------F

int battery_screen(int rep, int display)
{
   static int first=1;

   int acstat=0, battstat=0, battflag=0, percent=0;
  

   if(first)
   {
      first = 0;

      sprintf(buffer, "screen_set B name {APM stats: %s}\n", host);
      sock_send_string(sock, buffer);
      sock_send_string(sock, "widget_add B title title\n");
      sprintf(tmp, "widget_set B title {LCDPROC %s}\n", version);
      sock_send_string(sock, tmp);
      sock_send_string(sock, "widget_add B one string\n");
      if(lcd_hgt >= 4)
      {
         sock_send_string(sock, "widget_add B two string\n");
         sock_send_string(sock, "widget_add B three string\n");
         sock_send_string(sock, "widget_add B gauge hbar\n");
         sock_send_string(sock,
                          "widget_set B one 1 2 {AC: Unknown}\n");
         sock_send_string(sock,
                          "widget_set B two 1 3 {Batt: Unknown}\n");
         sock_send_string(sock,
                          "widget_set B three 1 4 {E                  F}\n");
         sock_send_string(sock, "widget_set B gauge 2 4 0\n");
      }
   }
   
   // Only run once every 16 frames...
   //if(rep&0x0f) return 0;
  
   get_batt_stat(&acstat, &battstat, &battflag, &percent);


   if(percent >= 0) sprintf(buffer, "%i%%", percent);
   else sprintf(buffer, "??%%");
   sprintf(tmp, "widget_set B title {Batt: %s: %s}\n", buffer, host);
  
   if(display) sock_send_string(sock, tmp);
  

   if(lcd_hgt >= 4) // 4-line version of the screen
   {
      sprintf(tmp, "widget_set B one 1 2 {");
      switch(acstat)
      {
         case 0: sprintf(tmp+strlen(tmp), "AC: Off}\n");
            break;
         case 1: sprintf(tmp+strlen(tmp), "AC: On}\n");
            break;
         case 2: sprintf(tmp+strlen(tmp), "AC: Backup}\n");
            break;
         default: sprintf(tmp+strlen(tmp), "AC: Unknown}\n");
            break;
      }
      
      if(display) sock_send_string(sock, tmp);


   
      sprintf(tmp, "widget_set B two 1 3 {");
      if(battflag == 0xff)
      {
         sprintf(tmp+strlen(tmp), "Battery Stat Unknown");
      }
      else
      {
         sprintf(tmp+strlen(tmp), "Batt:");
         if(battflag & 1)  sprintf(tmp+strlen(tmp), " High");
         if(battflag & 2)  sprintf(tmp+strlen(tmp), " Low");
         if(battflag & 4)  sprintf(tmp+strlen(tmp), " Critical");
         if(battflag & 8
            ||battstat == 3)  sprintf(tmp+strlen(tmp), " Charging");
         if(battflag & 128) sprintf(tmp+strlen(tmp), " (NONE)");
      } 
      sprintf(tmp+strlen(tmp), "}\n");
      if(display) sock_send_string(sock, tmp);
   

      if(percent > 0)
      {
         sprintf(tmp, "widget_set B gauge 2 4 %i\n",
                 (percent * ((lcd_wid-2)*lcd_cellwid)/100));
         if(display) sock_send_string(sock, tmp);
      }
   } // end if(lcd_hgt >= 4)
   else // two-line version of the screen
   {
      sprintf(tmp, "widget_set B one 1 2 {");
      if(acstat == 1)
         sprintf(tmp+strlen(tmp), "AC, ");
      
      if(battflag == 0xff)
      {
         sprintf(tmp+strlen(tmp), "No battery???");
      }
      else
      {
         sprintf(tmp+strlen(tmp), "Batt:");
         if(battflag & 1)  sprintf(tmp+strlen(tmp), " High");
         if(battflag & 2)  sprintf(tmp+strlen(tmp), " Low");
         if(battflag & 4)  sprintf(tmp+strlen(tmp), " Critical");
         if(battflag & 8
            ||battstat == 3)  sprintf(tmp+strlen(tmp), " Charging");
         if(battflag & 128) sprintf(tmp+strlen(tmp), " (NONE)");
      } 
      sprintf(tmp+strlen(tmp), "}\n");
      if(display) sock_send_string(sock, tmp);
   
   }
   
  return 0;
}