Script to parse the output of MOZ_LOG="nsStandardURL:5"

nsStandardUrlParse.py

#!/usr/bin/env python

import re
import sys

class URL:
	def __init__(self, ptr):
		self.ptr = ptr
		self.count = 0
		self.url = ""
		self.url_set = False
		self.trackB = False
	def setURL(self, url):
		if self.url_set:
			raise Exception("Trying to re-set a url that's already have a value. Current: " + self.url + " Attempted: " + url)
		self.url = url
		self.url_set = True
	def track(self):
		if self.trackB:
			raise Exception("Can't retrack something that's already tracked" + self.ptr)
		self.trackB = True
	def untrack(self):
		if not self.trackB:
			raise Exception("Can't untrack something that's not tracked? " + self.ptr)
		self.trackB = False
	def increment(self):
		self.count += 1
	def decrement(self):
		if self.count == 0:
			raise Exception("Can't decrement from 0")
		self.count -= 1
		if self.count == 0:
			self.url_set = False
	def __str__(self):
		return "%s, %s, %s, %s" % (self.ptr, self.count, self.trackB, self.url)

if __name__ == "__main__":
	if len(sys.argv) < 2:
		print "Usage:", sys.argv[0], "filename"
		sys.exit(1)

	createLine = "D/nsStandardURL Creating nsStandardURL @"
	destroyLine = "D/nsStandardURL Destroying nsStandardURL @"
	setSpecLine = "D/nsStandardURL nsStandardURL::SetSpec [this="
	trackLine = "And Tracking URL nsStandardURL @"
	untrackLine = "And Un-tracking URL nsStandardURL @"

	line = 0
	activeUrls = {}
	f = open(sys.argv[1])
	for l in f:
		l = l.strip()
		try:
			if setSpecLine in l:
				trimmed = l[l.index(setSpecLine) + len(setSpecLine):].strip()
				parts = trimmed.split(" ")

				ptr = parts[0].strip()
				spec = parts[1][5:-1]
				activeUrls[ptr].setURL(spec)
			elif trackLine in l:
				ptr = l[l.index(trackLine) + len(trackLine):].strip()
				activeUrls[ptr].track()
			elif untrackLine in l:
				ptr = l[l.index(untrackLine) + len(untrackLine):].strip()
				activeUrls[ptr].untrack()
			elif createLine in l:
				ptr = l[l.index(createLine) + len(createLine):].strip()
				if ptr not in activeUrls:
					activeUrls[ptr] = URL(ptr)
				activeUrls[ptr].increment()
			elif destroyLine in l:
				ptr = l[l.index(destroyLine) + len(destroyLine):].strip()
				if ptr not in activeUrls:
					raise Exception("We destroyed a URL we hadn't seen created! " + ptr)
				activeUrls[ptr].decrement()
		except Exception as e:
			print "Line", line, l
			print "     ", activeUrls[ptr]
			print "     ", e
		line += 1

	print "URLs we never destroyed:"
	for k in activeUrls:
		if activeUrls[k].count > 0:
			print activeUrls[k]