#!/bin/bash
# (c) 2014, Sasha Levin <sasha.levin@oracle.com>
#set -x

if [[ $# < 2 ]] {
	echo "Usage:"
	echo "	$0 [vmlinux] [base path] [modules path]"
	exit 1
}

setglobal vmlinux = $1
setglobal basepath = $2
setglobal modpath = $3TODO 
declare -A cache = ''TODO 
declare -A modcache = ''

proc parse_symbol {
	# The structure of symbol at this point is:
	#   ([name]+[offset]/[total length])
	#
	# For example:
	#   do_basic_setup+0x9c/0xbf

	if [[ $module == "" ]]  {
		var objfile = $vmlinux
	} elif [[ "${modcache[$module]+isset}" == "isset" ]] {
		var objfile = $(modcache[$module])
	} else {
		[[ $modpath == "" ]] && return
		var objfile = $[find $modpath -name $module.ko -print -quit]
		[[ $objfile == "" ]] && return
		compat array-assign modcache '$module' $objfile
	}

	# Remove the englobing parenthesis
	setglobal symbol = $(symbol#\()
	setglobal symbol = $(symbol%\))

	# Strip the symbol name so that we could look it up
	var name = $(symbol%+*)

	# Use 'nm vmlinux' to figure out the base address of said symbol.
	# It's actually faster to call it every time than to load it
	# all into bash.
	if [[ "${cache[$module,$name]+isset}" == "isset" ]] {
		var base_addr = $(cache[$module,$name])
	} else {
		var base_addr = $[nm $objfile | grep -i ' t ' | awk "/ $name\$/ {print \$1}" | head -n1]
		compat array-assign cache '$module,$name' $base_addr
	}
	# Let's start doing the math to get the exact address into the
	# symbol. First, strip out the symbol total length.
	var expr = $(symbol%/*)

	# Now, replace the symbol name with the base address we found
	# before.
	set expr = $(expr/$name/0x$base_addr)

	# Evaluate it to find the actual address
	set expr = $shExpr('expr')
	var address = $[printf "%x\n" $expr]

	# Pass it to addr2line to get filename and line number
	# Could get more than one result
	if [[ "${cache[$module,$address]+isset}" == "isset" ]] {
		var code = $(cache[$module,$address])
	} else {
		var code = $[addr2line -i -e $objfile $address]
		compat array-assign cache '$module,$address' $code
	}

	# addr2line doesn't return a proper error code if it fails, so
	# we detect it using the value it prints so that we could preserve
	# the offset/size into the function and bail out
	if [[ $code == "??:0" ]] {
		return
	}

	# Strip out the base of the path
	set code = $(code//$basepath/"")

	# In the case of inlines, move everything to same line
	set code = $(code//$'\n'/' ')

	# Replace old address with pretty line numbers
	setglobal symbol = ""$name ($code)""
}

proc decode_code {
	var scripts = $[dirname $(BASH_SOURCE[0])]

	echo $1 | $scripts/decodecode
}

proc handle_line {
	var words = ''

	# Tokenize
	read -a words <<<$1

	# Remove hex numbers. Do it ourselves until it happens in the
	# kernel

	# We need to know the index of the last element before we
	# remove elements because arrays are sparse
	var last = $shExpr(' ${#words[@]} - 1 ')

	for i in [$(!words[@])] {
		# Remove the address
		if [[ ${words[$i]} =~ \[\<([^]]+)\>\] ]] {
			unset words[$i]
		}

		# Format timestamps with tabs
		if [[ ${words[$i]} == \[ && ${words[$i+1]} == *\] ]] {
			unset words[$i]
			compat array-assign words '$i+1' $[printf "[%13s\n" $(words[$i+1])]
		}
	}

	if [[ ${words[$last]} =~ \[([^]]+)\] ]] {
		setglobal module = $(words[$last])
		setglobal module = $(module#\[)
		setglobal module = $(module%\])
		setglobal symbol = $(words[$last-1])
		unset words[$last-1]
	} else {
		# The symbol is the last element, process it
		setglobal symbol = $(words[$last])
		setglobal module = ''
	}

	unset words[$last]
	parse_symbol # modifies $symbol

	# Add up the line number to the symbol
	echo $(words[@]) "$symbol $module"
}

while read line {
	# Let's see if we have an address in the line
	if [[ $line =~ \[\<([^]]+)\>\]  ]] {
		# Translate address to line numbers
		handle_line $line
	# Is it a code line?
	} elif [[ $line == *Code:* ]] {
		decode_code $line
	} else {
		# Nothing special in this line, show it as is
		echo $line
	}
}