#!/usr/bin/env python

import argparse
import collections
import re
import sys


def parse_stack_name(line):
  # --- Thread 7f9fe9720340 (name: main/1) stack: ---
  m = re.match(r'\s*---\s*(.*)\s+stack:', line)
  if m:
    return m.group(1)
  # Thread 170 (Thread 0x7ffe7affb500 (LWP 38000)):
  m = re.match(r'Thread (\d+) \(Thread (0x[^\s]+) \(LWP (\d+)\)\):', line)
  if m:
    return m.group(2)
  m = re.match(r'Thread (\d+) \(LWP (\d+)\):', line)
  if m:
    return m.group(2)


def parse_stack_location(line):
  # PC:  0x7f9fe9759623: epoll_wait
  m = re.match(r'\s+PC:\s+0x[0-9a-fA-F]+', line)
  if m:
    return line
  # 0x5603eadc8ce1: Thread::ThreadBody(void*)
  m = re.match(r'\s+0x[0-9a-fA-F]+', line)
  if m:
    return line
  # #0  pthread_cond_wait@@GLIBC_2.3.2 () at ../sysdeps/unix/sysv/linux/x86_64/pthread_cond_wait.S:185
  m = re.match(r'#\d+\s+', line)
  if m:
    return re.sub(r'([a-zA-Z_]+)=(0x[a-fA-F0-9]+|[+\-]?\d+(\.\d*)?)', '\\1=X',
                  line)


def is_same_stack(line):
  # [same as previous thread]
  return re.search(r'\[same as previous thread\]', line)


def parse_stacks(lines):
  stacks = collections.defaultdict(list)
  name, stack, last_stack = None, '', ''
  for line in lines:
    if name is not None:
      location = parse_stack_location(line)
      if location:
        stack += location
        continue
      if not stack and is_same_stack(line) and last_stack:
        stacks[last_stack].append(name)
        name, stack = None, ''
        continue
      if stack:
        stacks[stack].append(name)
        last_stack = stack
        stack = ''
        name = parse_stack_name(line)
        continue
    else:
      name = parse_stack_name(line)
  return stacks


def create_report(args, stacks):
  mrkeys = sorted(stacks.keys(), key=lambda x: len(stacks[x]), reverse=True)
  for key in mrkeys:
    print('STACK (count={}):'.format(len(stacks[key])))
    print('{}'.format(key))
    print('LOCATIONS:')
    for name in stacks[key]:
      print('  {}'.format(name))
    print('')


def process_stack_lines(ln_iter, args):
  stacks = parse_stacks(ln_iter)
  create_report(args, stacks)


def process_stacks(args):
  fd = sys.stdin if args.input is None else open(args.input, 'r')
  process_stack_lines(fd, args)


if __name__ == '__main__':
  arg_parser = argparse.ArgumentParser()
  arg_parser.add_argument('--input', type=str)
  args, files = arg_parser.parse_known_args()
  args.files = files
  process_stacks(args)