#!/bin/sh
#
#   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., 675 Mass Ave, Cambridge, MA 02139, USA.
#
# Author: Marc Vertes, mailto:mvertes@free.fr, http://mvertes.free.fr
# Version 1.0
#
usage()
{
	cat << \EOT
NAME
  cgprof - generate colored call graph for profiled executables

SYNOPSIS
  cgprof [-h] [-T dev] [-g gmon_data] [gprof_file]

DESCRIPTION
  cgprof generate a function calling graph for a profiled executable. The
  executable must have been compiled and linked to output data suitable for
  gprof(1) (look at -pg option of gcc(1)). If no -T option is given,
  output is dot(1) commands. All the results are printed on standard
  output. cgprof takes gprof_file as input, or standard input.

  The result is a directed acyclic graph (DAG), where nodes represent
  functions traversed during the program execution, and edges function
  calls (arrow is from the caller to the called).

  Node colors represent the cumulative execution time spent by a
  function and its children. Colors range from intense red (100 % time) to
  pale violet (0 %), like a rainbow. A node is white filled when it has
  no time execution data available, which may be the case for profiling
  functions or not instrumented functions.

  cgprof helps to have a better understanding of program structure and
  execution. It makes hot spots identification visual and intuitive,
  and provides a minimum code coverage function.

OPTIONS
  -h      Display this help text.
  -T dev  This option sets the output format to dev. Possible values of
          dev are :
	  X    X11 output, with direct previewing using dotty(1).
	  ps   Postscript output, using dot(1) processor. The drawing will be
	       sized to fill one landscape page.
EXAMPLE
  to print a report from execution of test_hash, run the following
  command:
    
      $ cc -pg -o test_hash test_hash.c
      $ test_hash < test_data
      $ gprof test_hash | cgprof -Tps | lpr

SEE ALSO
  gprof(1), dot(1), dotty(1), cc(1).

HISTORY
  cgprof is inspired by a gprof2dot, a similar tool from AT&T Research Labs, 
  distributed part of graphviz (http://www.graphviz.org) which includes
  also dot tools.

AUTHOR
  Marc Vertes <mvertes@free.fr>
EOT
}

g2d()
{
	echo "digraph gprof {"
	echo "	rankdir=LR;"
	echo "	node [style=filled];"
	echo "	node [color=\"0.1 0.0 1.0\"];"

	awk '
	BEGIN { 
		start = 0 
		maxhue = 0.6	# from red (.0) to magenta (.6), cf rainbow
		minsat = 0.1	# low saturation
		bri = 1.0	# brightness, always 100%
	}
	#/Call graph/		{ start = 1; next }
	/granularity:/		{ start = 1; next }
	start == 0		{ next }
	$1 == ""		{ exit }
	$1 == "<spontaneous>"	{ next }
	$1 == "granularity:"	{ next }
	$1 == "called/total"	{ next }
	$1 == "index"		{ next }
	NF == 0			{ next }
	/<cycle [0-9]* as a whole>/	{ next }
	{ gsub(/<.*>/, "") }
	$1 ~ /\[/ { 
		caller = $(NF -1)
		cost = $2 / 100.0
		if (cost > 0.0) {
			# following formulas are totally empirical
			hue = maxhue * (1.0 - cost)
			sat = minsat + (3.0 - minsat) * cost
		} else {
			hue = maxhue
			sat = minsat
		}
		printf("\t\"%s\" [color=\"%.3f %.3f %.3f\"];\n", 
			caller, hue, sat, bri)
		next 
	}
	/^---/ { 
		for (i = 1; i <= nc; i++) {
			if (caller == "") caller = called[i]
			print "\t\"" called[i] "\" -> \"" caller "\";"
		}
		caller = ""; nc = 0; next 
	}
	caller == "" { called[++nc] = $(NF - 1) }
	caller != "" { print "\t\"" caller "\" -> \"" $(NF -1) "\";" }
	' $* | sort -u

	echo "}"
}

dev=""

while getopts :hT: opt
do
	case $opt in
	T) dev=$OPTARG;;
	*) usage; exit;;
	esac
done
shift $(($OPTIND - 1))

case $dev in
	X)  post="dotty -";;
	ps) post="dot -Tps -Gsize=\"11,17\" -Grotate=90";;
	*)  post="cat"
esac

g2d $* | eval $post