sugar-toolkit-gtk3/services/console/interface/xo/cpu.py

##!/usr/bin/env python

# Copyright (C) 2007, Eduardo Silva (edsiper@gmail.com).
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

import os
import sys
import gtk
import string
import gobject

import procmem

class CPU_Usage:
    
    _CPU_HZ = 0
    _last_jiffies = 0
    _times = 0

    def __init__(self):
        self._CPU_HZ = os.sysconf(2)

    def _get_CPU_data(self):
        # Uptime info
        stat_file = "/proc/stat"

        try:
            infile = file(stat_file, "r")
        except:
            print "Error trying uptime file"
            return -1

        stat_line = infile.readline()
        cpu_info = string.split(stat_line, ' ')
        infile.close()

        return cpu_info
    
    def _get_CPU_usage(self):
        
        cpu_info = self._get_CPU_data()
        
        used_jiffies = (int(cpu_info[2]) + int(cpu_info[3]) + int(cpu_info[4]))
        
        if self._times ==0:
            self._last_jiffies = used_jiffies
            self._times +=1
            return 0

        new_ujiffies = (used_jiffies - self._last_jiffies)
        new_ajiffies = ((self.frequency/1000) * self._CPU_HZ)

        if new_ajiffies <= 0:
            pcpu = 0.0
        else:
            pcpu = ((new_ujiffies*100)/new_ajiffies)

        if pcpu >100:
            pcpu = 100

        self._times +=1
        self._last_jiffies = used_jiffies
        
        return pcpu

class XO_CPU(gtk.Frame):
    _frequency_timer = 1

    def __init__(self):
        gtk.Frame.__init__(self, 'System CPU Usage')
        self.set_border_width(10)

        self._updated = False
        width = (gtk.gdk.screen_width() * 99 / 100) - 50
        height = (gtk.gdk.screen_height() * 15 / 100) - 20

        self._graphic = HorizontalGraphic()
        self._graphic.set_size_request(width, height)

        fixed = gtk.Fixed()
        fixed.set_border_width(10)
        fixed.add(self._graphic)

        self.add(fixed)

        self._DRW_CPU = CPU_Usage()
        self._DRW_CPU.frequency = 1000 # 1 Second

        gobject.timeout_add(self._DRW_CPU.frequency, self._update_cpu_usage)

    def _update_cpu_usage(self):
        self._cpu = self._DRW_CPU._get_CPU_usage()
        self._updated = True

        #print "Sending: " + str(self._cpu)
        self.set_label('System CPU Usage: ' + str(self._cpu) + '%')
        self._graphic.draw_value(self._cpu)
        return True

class HorizontalGraphic(gtk.DrawingArea):
    _MARGIN = 5
    _LINE_WIDTH = 2
    _GRAPH_OFFSET = 7
    _range_x = []
    _range_y = []
    _frequency_timer = 0

    def __init__(self):
        gtk.DrawingArea.__init__(self)
        self.connect('expose-event', self.do_expose)
        self.connect('size-allocate', self._change_size_cb)

        self._buffer = [0]
    
    def do_expose(self, widget, event):
        context = widget.window.cairo_create()
        context.rectangle(0, 0, self._width - 1, self._height - 1)
        context.set_source_rgb (0,0,0)
        context.fill_preserve()
        context.set_line_width(self._LINE_WIDTH)

        if event.area.x == 0:
            draw_all = True

            self._draw_border_lines(context)
            context.stroke()            
        else:
            draw_all = False
            context.rectangle(event.area.x, event.area.y, event.area.width, event.area.height)
            context.clip()

        context.set_source_rgb(1, 1, 1)
        self._draw_buffer(event, widget, context, draw_all)
        context.stroke()

        self._updated = False
        return False

    def draw_value(self, percent):
        redraw_all = False

        if (len(self._buffer) + 1) *self._GRAPH_OFFSET >= self._width:
            redraw_all = True
            self._buffer = [self._buffer[-1]]
            length = 1
        else:
            length = len(self._buffer) - 1

        self._buffer.append(percent)
        self._updated = True

        if redraw_all:
            area_x = 0
            area_y = 0
            height = self._height
            width = self._width
        else:
            area_x = (length*self._GRAPH_OFFSET)
            area_y = self._graph_y
            width = self._GRAPH_OFFSET * 2
            height = self._graph_height

        self.queue_draw_area(area_x, area_y, width, height)
        self._frequency_timer += 1

        return True

    def _draw_border_lines(self, context):
        context.set_source_rgb(1, 1, 1)
        self._draw_line(context, self._MARGIN, self._MARGIN, self._MARGIN, self._height - self._MARGIN)
        self._draw_line(context, self._MARGIN, self._height - self._MARGIN - 1, self._width - self._MARGIN, self._height - self._MARGIN - 1)

    def _draw_line(self, context, from_x, from_y, to_x, to_y):               
        #print ""
        #print "DRAWING LINE"
        #print "from: " + str(from_x) + "," + str(from_y) + "," + str(to_x) + "," + str(to_y)

        context.move_to(from_x, from_y)
        context.line_to(to_x, to_y)         

    def _draw_buffer(self, event, drwarea, context, draw_all=True):
        buffer_offset = 0
        freq = 1 # Frequency timer

        length = len(self._buffer)
        
        if length == 0:
            return

        # Context properties
        context.set_line_width(self._LINE_WIDTH)
        context.set_source_rgb(0,1,0)

        if draw_all == True:
            buffer_offset = 0
            freq = 0
        else:
            freq = buffer_offset = (event.area.x/self._GRAPH_OFFSET)

        for percent in self._buffer[buffer_offset:length]:
            if buffer_offset == 0:
                from_y = self._height - self._GRAPH_OFFSET
                from_x = self._GRAPH_OFFSET
            else:
                from_y = self._get_y(self._buffer[buffer_offset-1])
                from_x = (freq * self._GRAPH_OFFSET)

            to_x = (freq+1) * self._GRAPH_OFFSET
            to_y = self._get_y(percent)

            self._draw_line(context, from_x, from_y, to_x, to_y)
            buffer_offset+=1
            freq+=1

        context.stroke()

    def _get_y(self, percent):
        y_value = self._GRAPH_OFFSET + (self._graph_height - ((percent*self._graph_height)/100))
        return int(y_value) 

    def _change_size_cb(self, widget, allocation):
        self._width = allocation.width
        self._height = allocation.height

        self._graph_x = self._MARGIN + self._LINE_WIDTH
        self._graph_y = self._MARGIN + self._LINE_WIDTH
        self._graph_width = self._width - (self._MARGIN + self._LINE_WIDTH)
        self._graph_height = self._height - ((self._MARGIN + self._LINE_WIDTH)*2)


# Just for test >:)
#graph = HorizontalGraphic()
#graph.set_size_request(400,200)
"""
window = gtk.Window()
window.set_size_request(500, 250)
window.add(XO_CPU())
window.show_all()
gtk.main()
"""