-- Permission is hereby granted, free of charge, to any person
-- obtaining a copy of this software and associated documentation files
-- (the "Software"), to deal in the Software without restriction,
-- including without limitation the rights to use, copy, modify, merge,
-- publish, distribute, sublicense, and/or sell copies of the Software,
-- and to permit persons to whom the Software is furnished to do so,
-- subject to the following conditions:
--
-- The above copyright notice and this permission notice shall be
-- included in all copies or substantial portions of the Software.
--
-- THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-- EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-- MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-- NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
-- BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
-- ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
-- CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
-- SOFTWARE.

--based on callgraph from http://publicclu2.blogspot.co.uk/2013/05/call-graph-generation.html
--translated to lua by Domingo Alvarez Duarte mingodad_at_gmail_dot_com

local strFormat = string.format

local function capture(cmd)
  local f = assert(io.popen(cmd, 'r'))
  local s = assert(f:read('*a'))
  f:close()
  return s
end

local prog_name="callgraph"

if  #arg < 1 then
    print( strFormat("Usage: %s EXECUTABLE [ARGS...]", prog_name))
    print( strFormat("\nExample: %s ~/bin/test-program foo 23", prog_name))
    os.exit( 1 )
end

-- Sanity checks.
local FILE=arg[1]

local fd, err = io.open(FILE)
if err then
    print(strFormat("%s: Unable to find executable '%s'", prog_name, FILE))
    os.exit( 1 )
end

fd:close()

local str = capture(strFormat("gdb --eval-command=quit %s 2>&1", FILE))

if str:match("(no debugging symbols found)") or str:match("(not in executable format)") then
    print(strFormat([==[
%s: Can't print call graph for '%s' because it's not a
binary executable compiled with debugging symbols.
]==], prog_name, FILE))
    os.exit( 1 )
end

-- Set up temporary files.
local TRACE_file_name = FILE .. ".gdb.trace"
local TRACE_fd=io.open(TRACE_file_name, "w")

local GETFUNCS_file_name = FILE .. ".gdb.funcs"
local GETFUNCS_fd=io.open(GETFUNCS_file_name, "w")

-- Take control of GDB and print call graph.
GETFUNCS_fd:write([[
set height 0
info functions
]])
GETFUNCS_fd:close()

str = capture(strFormat("gdb --batch --command=%s %s 2>/dev/null", GETFUNCS_file_name, FILE))

--print(str)
--os.exit(1)

local  total = 0;

TRACE_fd:write([[
set width 0
set height 0
set verbose off
]])

local functions_to_break = {}

for fn in str:gmatch("([a-zA-Z_][a-zA-Z0-9_]+)%b()") do
	TRACE_fd:write(strFormat("break %s\n", fn));
	functions_to_break[fn] = 0;
	total = total + 1;
end

for i = 1, total do
	TRACE_fd:write(strFormat("commands %d\n", i));
	--TRACE_fd:write("info args\n");
	TRACE_fd:write( "backtrace 2\ncontinue\nend\n");
end
TRACE_fd:write( "run\n");
TRACE_fd:close()

local cmd_args = ""
for i=2, #arg do
	cmd_args = cmd_args .. " " .. arg[i]
end
--print(FILE, cmd_args)

local cmd = strFormat("gdb --batch --command=%s --tty=/dev/null --args %s %s 2>/dev/null", TRACE_file_name, FILE, cmd_args)
--print(cmd)

local fd_cmd = assert(io.popen(cmd, 'r'))

local function joinLines(s)
	if not s:match(":%d+$") then
		--parameters have embedded new lines
		while(true) do
			local new_line = fd_cmd:read('*l')
			if not new_line then break end
			s = s .. "\\n" .. new_line
			if new_line:match(":%d+$") then
				break
			end
		end
	end
	return s
end

local isrecord = false;
local callee = "";
local caller = "*INITIAL*";
local params = "";
  
while(true) do
	local s = fd_cmd:read('*l')
	if not s then break end
	--print(s)
	if s:match("^Breakpoint [0-9]+,") then
		isrecord = true;
		s = joinLines(s)
		callee, params = s:match("^Breakpoint [0-9]+,%s*(%S+)%s*(%(.*%))%s+at%s+%S+:%d+$");
		local call_count = functions_to_break[callee]
		if call_count then
			functions_to_break[callee] = call_count + 1
		else
			print("Bad match", callee, s)
		end
	elseif s:match("^#1%s+") then
		if (isrecord) then
			s = joinLines(s)
			caller =s:match("^#1%s+%S+%s+%S+%s+(%S+)");
		end
	elseif #s == 0 then
		if (isrecord and (caller ~= "*INITIAL*")) then
			print(strFormat("%s %s %s", caller, callee, params));
			callee = "";
			caller = "";
			params = "";
		end
	else
		--print("No match line", s)
	end
end
fd_cmd:close()

local functions_calls = {}
for fn, cnt in pairs(functions_to_break) do
	table.insert(functions_calls, {fn, cnt})
end

--table.sort(functions_calls, function(a,b) return a[2] > b[2] end)
table.sort(functions_calls, function(a,b)
		if a[2] == b[2] then
			return a[1] < b[1]
		end
		return a[2] > b[2] 
	end)

print("Function calls count")
for k,v in ipairs(functions_calls) do
	print(v[1], v[2])
end