pybootchartgui: visualize /proc/net/dev network stats in graphs

diff --git a/pybootchartgui/pybootchartgui/draw.py b/pybootchartgui/pybootchartgui/draw.py
index c6e67833ab..16739a0fa1 100644
--- a/pybootchartgui/pybootchartgui/draw.py
+++ b/pybootchartgui/pybootchartgui/draw.py
@@ -69,6 +69,11 @@  CPU_COLOR = (0.40, 0.55, 0.70, 1.0)
 IO_COLOR = (0.76, 0.48, 0.48, 0.5)
 # Disk throughput color.
 DISK_TPUT_COLOR = (0.20, 0.71, 0.20, 1.0)
+
+BYTES_RECEIVED_COLOR = (0.0, 0.0, 1.0, 1.0)
+BYTES_TRANSMITTED_COLOR = (1.0, 0.0, 0.0, 1.0)
+BYTES_RECEIVE_DIFF_COLOR = (0.0, 0.0, 1.0, 0.3)
+BYTES_TRANSMIT_DIFF_COLOR = (1.0, 0.0, 0.0, 0.3)
 # CPU load chart color.
 FILE_OPEN_COLOR = (0.20, 0.71, 0.71, 1.0)
 # Mem cached color
@@ -437,6 +442,49 @@  def render_charts(ctx, options, clip, trace, curr_y, w, h, sec_w):
 
         curr_y = curr_y + 30 + bar_h
 
+    if trace.net_stats:
+        for iface, samples in trace.net_stats.items():
+            max_received_sample = max(samples, key=lambda s: s.received_bytes)
+            max_transmitted_sample = max(samples, key=lambda s: s.transmitted_bytes)
+            max_receive_diff_sample = max(samples, key=lambda s: s.receive_diff)
+            max_transmit_diff_sample = max(samples, key=lambda s: s.transmit_diff)
+
+            draw_text(ctx, "Iface: %s" % (iface), TEXT_COLOR, off_x, curr_y+20)
+            draw_legend_line(ctx, "Bytes received (max %d)" % (max_received_sample.received_bytes),
+                             BYTES_RECEIVED_COLOR, off_x+150, curr_y+20, leg_s)
+            draw_legend_line(ctx, "Bytes transmitted (max %d)" % (max_transmitted_sample.transmitted_bytes),
+                             BYTES_TRANSMITTED_COLOR, off_x+400, curr_y+20, leg_s)
+            draw_legend_box(ctx, "Bytes receive diff (max %d)" % (max_receive_diff_sample.receive_diff),
+                             BYTES_RECEIVE_DIFF_COLOR, off_x+650, curr_y+20, leg_s)
+            draw_legend_box(ctx, "Bytes transmit diff (max %d)" % (max_transmit_diff_sample.transmit_diff),
+                             BYTES_TRANSMIT_DIFF_COLOR, off_x+900, curr_y+20, leg_s)
+
+
+            chart_rect = (off_x, curr_y + 30, w, bar_h)
+            if clip_visible(clip, chart_rect):
+                draw_box_ticks(ctx, chart_rect, sec_w)
+                draw_annotations(ctx, proc_tree, trace.times, chart_rect)
+
+            if clip_visible (clip, chart_rect):
+                draw_chart (ctx, BYTES_RECEIVED_COLOR, False, chart_rect, \
+                        [(sample.time, sample.received_bytes) for sample in samples], \
+                        proc_tree, None)
+
+                draw_chart (ctx, BYTES_TRANSMITTED_COLOR, False, chart_rect, \
+                        [(sample.time, sample.transmitted_bytes) for sample in samples], \
+                        proc_tree, None)
+
+            if clip_visible (clip, chart_rect):
+                draw_chart (ctx, BYTES_RECEIVE_DIFF_COLOR, True, chart_rect, \
+                        [(sample.time, sample.receive_diff) for sample in samples], \
+                        proc_tree, None)
+
+                draw_chart (ctx, BYTES_TRANSMIT_DIFF_COLOR, True, chart_rect, \
+                        [(sample.time, sample.transmit_diff) for sample in samples], \
+                        proc_tree, None)
+
+            curr_y = curr_y + 30 + bar_h
+
     # render CPU pressure chart
     if trace.cpu_pressure:
         max_sample_avg = max (trace.cpu_pressure, key = lambda s: s.avg10)
diff --git a/pybootchartgui/pybootchartgui/parsing.py b/pybootchartgui/pybootchartgui/parsing.py
index 144a16c723..72a54c6ba5 100644
--- a/pybootchartgui/pybootchartgui/parsing.py
+++ b/pybootchartgui/pybootchartgui/parsing.py
@@ -48,6 +48,7 @@  class Trace:
         self.filename = None
         self.parent_map = None
         self.mem_stats = []
+        self.net_stats = []
         self.monitor_disk = None
         self.cpu_pressure = []
         self.io_pressure = []
@@ -557,6 +558,21 @@  def _parse_monitor_disk_log(file):
 
     return disk_stats
 
+
+def _parse_reduced_net_log(file):
+    net_stats = {}
+    for time, lines in _parse_timed_blocks(file):
+
+        for line in lines:
+            parts = line.split()
+            iface = parts[0][:-1]
+            if iface not in net_stats:
+                net_stats[iface] = [NetSample(time, iface, int(parts[1]), int(parts[2]), int(parts[3]), int(parts[4]))]
+            else:
+                net_stats[iface].append(NetSample(time, iface, int(parts[1]), int(parts[2]), int(parts[3]), int(parts[4])))
+    return net_stats
+
+
 def _parse_pressure_logs(file, filename):
     """
     Parse file for "some" pressure with 'avg10', 'avg60' 'avg300' and delta total values
@@ -767,6 +783,8 @@  def _do_parse(writer, state, filename, file):
         state.cmdline = _parse_cmdline_log(writer, file)
     elif name == "monitor_disk.log":
         state.monitor_disk = _parse_monitor_disk_log(file)
+    elif name == "reduced_proc_net.log":
+        state.net_stats = _parse_reduced_net_log(file)
     #pressure logs are in a subdirectory
     elif name == "cpu.log":
         state.cpu_pressure = _parse_pressure_logs(file, name)
diff --git a/pybootchartgui/pybootchartgui/samples.py b/pybootchartgui/pybootchartgui/samples.py
index a70d8a5a28..7c92d2ce6a 100644
--- a/pybootchartgui/pybootchartgui/samples.py
+++ b/pybootchartgui/pybootchartgui/samples.py
@@ -37,6 +37,16 @@  class CPUSample:
         return str(self.time) + "\t" + str(self.user) + "\t" + \
                str(self.sys) + "\t" + str(self.io) + "\t" + str (self.swap)
 
+
+class NetSample:
+    def __init__(self, time, iface, received_bytes, transmitted_bytes, receive_diff, transmit_diff):
+        self.time = time
+        self.iface = iface
+        self.received_bytes = received_bytes
+        self.transmitted_bytes = transmitted_bytes
+        self.receive_diff = receive_diff
+        self.transmit_diff = transmit_diff
+
 class CPUPressureSample:
     def __init__(self, time, avg10, avg60, avg300, deltaTotal):
         self.time = time