#!/usr/bin/env python3
#===- lib/asan/scripts/asan_symbolize.py -----------------------------------===#
#
#                     The LLVM Compiler Infrastructure
#
# This file is distributed under the University of Illinois Open Source
# License. See LICENSE.TXT for details.
#
#===------------------------------------------------------------------------===#
import bisect
import os
import re
import subprocess
import sys

llvm_symbolizer = None
symbolizers = {}
filetypes = {}
vmaddrs = {}
DEBUG = False


# FIXME: merge the code that calls fix_filename().
def fix_filename(file_name):
  for path_to_cut in sys.argv[1:]:
    file_name = re.sub('.*' + path_to_cut, '', file_name)
  file_name = re.sub('.*asan_[a-z_]*.cc:[0-9]*', '_asan_rtl_', file_name)
  file_name = re.sub('.*crtstuff.c:0', '???:0', file_name)
  return file_name


class Symbolizer(object):
  def __init__(self):
    pass

  def symbolize(self, addr, binary, offset):
    """Symbolize the given address (pair of binary and offset).

    Overridden in subclasses.
    Args:
        addr: virtual address of an instruction.
        binary: path to executable/shared object containing this instruction.
        offset: instruction offset in the @binary.
    Returns:
        list of strings (one string for each inlined frame) describing
        the code locations for this instruction (that is, function name, file
        name, line and column numbers).
    """
    return None


class LLVMSymbolizer(Symbolizer):
  def __init__(self, symbolizer_path):
    super(LLVMSymbolizer, self).__init__()
    self.symbolizer_path = symbolizer_path
    self.pipe = self.open_llvm_symbolizer()

  def open_llvm_symbolizer(self):
    if not os.path.exists(self.symbolizer_path):
      return None
    cmd = [self.symbolizer_path,
           '--use-symbol-table=true',
           '--demangle=false',
           '--functions=true',
           '--inlining=true']
    if DEBUG:
      print(' '.join(cmd))
    return subprocess.Popen(cmd, stdin=subprocess.PIPE,
                            stdout=subprocess.PIPE)

  def symbolize(self, addr, binary, offset):
    """Overrides Symbolizer.symbolize."""
    if not self.pipe:
      return None
    result = []
    try:
      symbolizer_input = '%s %s' % (binary, offset)
      if DEBUG:
        print(symbolizer_input)
      self.pipe.stdin.write(symbolizer_input)
      self.pipe.stdin.write('\n')
      while True:
        function_name = self.pipe.stdout.readline().rstrip()
        if not function_name:
          break
        file_name = self.pipe.stdout.readline().rstrip()
        file_name = fix_filename(file_name)
        if (not function_name.startswith('??') and
            not file_name.startswith('??')):
          # Append only valid frames.
          result.append('%s in %s %s' % (addr, function_name,
                                         file_name))
    except Exception:
      result = []
    if not result:
      result = None
    return result


def LLVMSymbolizerFactory(system):
  symbolizer_path = os.getenv('LLVM_SYMBOLIZER_PATH')
  if not symbolizer_path:
    # Assume llvm-symbolizer is in PATH.
    symbolizer_path = 'llvm-symbolizer'
  return LLVMSymbolizer(symbolizer_path)


class Addr2LineSymbolizer(Symbolizer):
  def __init__(self, binary):
    super(Addr2LineSymbolizer, self).__init__()
    self.binary = binary
    self.pipe = self.open_addr2line()

  def open_addr2line(self):
    cmd = ['addr2line', '-f', '-e', self.binary]
    if DEBUG:
      print(' '.join(cmd))
    return subprocess.Popen(cmd,
                            stdin=subprocess.PIPE, stdout=subprocess.PIPE)

  def symbolize(self, addr, binary, offset):
    """Overrides Symbolizer.symbolize."""
    if self.binary != binary:
      return None
    try:
      self.pipe.stdin.write(offset)
      self.pipe.stdin.write('\n')
      function_name = self.pipe.stdout.readline().rstrip()
      file_name = self.pipe.stdout.readline().rstrip()
    except Exception:
      function_name = ''
      file_name = ''
    file_name = fix_filename(file_name)
    return ['%s in %s %s' % (addr, function_name, file_name)]


class DarwinSymbolizer(Symbolizer):
  def __init__(self, addr, binary):
    super(DarwinSymbolizer, self).__init__()
    self.binary = binary
    # Guess which arch we're running. 10 = len('0x') + 8 hex digits.
    if len(addr) > 10:
      self.arch = 'x86_64'
    else:
      self.arch = 'i386'
    self.vmaddr = None
    self.pipe = None

  def write_addr_to_pipe(self, offset):
    self.pipe.stdin.write('0x%x' % int(offset, 16))
    self.pipe.stdin.write('\n')

  def open_atos(self):
    if DEBUG:
      print('atos -o %s -arch %s' % (self.binary, self.arch))
    cmdline = ['atos', '-o', self.binary, '-arch', self.arch]
    self.pipe = subprocess.Popen(cmdline,
                                 stdin=subprocess.PIPE,
                                 stdout=subprocess.PIPE,
                                 stderr=subprocess.PIPE)

  def symbolize(self, addr, binary, offset):
    """Overrides Symbolizer.symbolize."""
    if self.binary != binary:
      return None
    self.open_atos()
    self.write_addr_to_pipe(offset)
    self.pipe.stdin.close()
    atos_line = self.pipe.stdout.readline().rstrip()
    # A well-formed atos response looks like this:
    #   foo(type1, type2) (in object.name) (filename.cc:80)
    match = re.match(r'^(.*) \(in (.*)\) \((.*:\d*)\)$', atos_line)
    if DEBUG:
      print(f'atos_line: {atos_line}')
    if match:
      function_name = match.group(1)
      function_name = re.sub(r'\(.*?\)', '', function_name)
      file_name = fix_filename(match.group(3))
      return ['%s in %s %s' % (addr, function_name, file_name)]
    else:
      return ['%s in %s' % (addr, atos_line)]


# Chain several symbolizers so that if one symbolizer fails, we fall back
# to the next symbolizer in chain.
class ChainSymbolizer(Symbolizer):
  def __init__(self, symbolizer_list):
    super(ChainSymbolizer, self).__init__()
    self.symbolizer_list = symbolizer_list

  def symbolize(self, addr, binary, offset):
    """Overrides Symbolizer.symbolize."""
    for symbolizer in self.symbolizer_list:
      if symbolizer:
        result = symbolizer.symbolize(addr, binary, offset)
        if result:
          return result
    return None

  def append_symbolizer(self, symbolizer):
    self.symbolizer_list.append(symbolizer)


def BreakpadSymbolizerFactory(binary):
  suffix = os.getenv('BREAKPAD_SUFFIX')
  if suffix:
    filename = binary + suffix
    if os.access(filename, os.F_OK):
      return BreakpadSymbolizer(filename)
  return None


def SystemSymbolizerFactory(system, addr, binary):
  if system == 'Darwin':
    return DarwinSymbolizer(addr, binary)
  elif system == 'Linux':
    return Addr2LineSymbolizer(binary)


class BreakpadSymbolizer(Symbolizer):
  def __init__(self, filename):
    super(BreakpadSymbolizer, self).__init__()
    self.filename = filename
    lines = file(filename).readlines()
    self.files = []
    self.symbols = {}
    self.address_list = []
    self.addresses = {}
    # MODULE mac x86_64 A7001116478B33F18FF9BEDE9F615F190 t
    fragments = lines[0].rstrip().split()
    self.arch = fragments[2]
    self.debug_id = fragments[3]
    self.binary = ' '.join(fragments[4:])
    self.parse_lines(lines[1:])

  def parse_lines(self, lines):
    cur_function_addr = ''
    for line in lines:
      fragments = line.split()
      if fragments[0] == 'FILE':
        assert int(fragments[1]) == len(self.files)
        self.files.append(' '.join(fragments[2:]))
      elif fragments[0] == 'PUBLIC':
        self.symbols[int(fragments[1], 16)] = ' '.join(fragments[3:])
      elif fragments[0] in ['CFI', 'STACK']:
        pass
      elif fragments[0] == 'FUNC':
        cur_function_addr = int(fragments[1], 16)
        if not cur_function_addr in self.symbols.keys():
          self.symbols[cur_function_addr] = ' '.join(fragments[4:])
      else:
        # Line starting with an address.
        addr = int(fragments[0], 16)
        self.address_list.append(addr)
        # Tuple of symbol address, size, line, file number.
        self.addresses[addr] = (cur_function_addr,
                                int(fragments[1], 16),
                                int(fragments[2]),
                                int(fragments[3]))
    self.address_list.sort()

  def get_sym_file_line(self, addr):
    key = None
    if addr in self.addresses.keys():
      key = addr
    else:
      index = bisect.bisect_left(self.address_list, addr)
      if index == 0:
        return None
      else:
        key = self.address_list[index - 1]
    sym_id, size, line_no, file_no = self.addresses[key]
    symbol = self.symbols[sym_id]
    filename = self.files[file_no]
    if addr < key + size:
      return symbol, filename, line_no
    else:
      return None

  def symbolize(self, addr, binary, offset):
    if self.binary != binary:
      return None
    res = self.get_sym_file_line(int(offset, 16))
    if res:
      function_name, file_name, line_no = res
      result = ['%s in %s %s:%d' % (
          addr, function_name, file_name, line_no)]
      print(result)
      return result
    else:
      return None


class SymbolizationLoop(object):
  def __init__(self, binary_name_filter=None):
    # Used by clients who may want to supply a different binary name.
    # E.g. in Chrome several binaries may share a single .dSYM.
    self.binary_name_filter = binary_name_filter
    self.system = os.uname()[0]
    if self.system in ['Linux', 'Darwin']:
      self.llvm_symbolizer = LLVMSymbolizerFactory(self.system)
    else:
      raise Exception('Unknown system')

  def symbolize_address(self, addr, binary, offset):
    # Use the chain of symbolizers:
    # Breakpad symbolizer -> LLVM symbolizer -> addr2line/atos
    # (fall back to next symbolizer if the previous one fails).
    if not binary in symbolizers:
      symbolizers[binary] = ChainSymbolizer(
          [BreakpadSymbolizerFactory(binary), self.llvm_symbolizer])
    result = symbolizers[binary].symbolize(addr, binary, offset)
    if result is None:
      # Initialize system symbolizer only if other symbolizers failed.
      symbolizers[binary].append_symbolizer(
          SystemSymbolizerFactory(self.system, addr, binary))
      result = symbolizers[binary].symbolize(addr, binary, offset)
    # The system symbolizer must produce some result.
    assert result
    return result

  def print_symbolized_lines(self, symbolized_lines):
    if not symbolized_lines:
      print(self.current_line)
    else:
      for symbolized_frame in symbolized_lines:
        print('    #' + str(self.frame_no) + ' ' + symbolized_frame.rstrip())
        self.frame_no += 1

  def process_stdin(self):
    self.frame_no = 0

    if sys.version_info[0] == 2:
      sys.stdout = os.fdopen(sys.stdout.fileno(), 'w', 0)
    else:
      # Unbuffered output is not supported in Python 3
      sys.stdout = os.fdopen(sys.stdout.fileno(), 'w')

    while True:
      line = sys.stdin.readline()
      if not line: break
      self.current_line = line.rstrip()
      #0 0x7f6e35cf2e45  (/blah/foo.so+0x11fe45)
      stack_trace_line_format = (
          r'^( *#([0-9]+) *)(0x[0-9a-f]+) *\((.*)\+(0x[0-9a-f]+)\)')
      match = re.match(stack_trace_line_format, line)
      if not match:
        print(self.current_line)
        continue
      if DEBUG:
        print(line)
      _, frameno_str, addr, binary, offset = match.groups()
      if frameno_str == '0':
        # Assume that frame #0 is the first frame of new stack trace.
        self.frame_no = 0
      original_binary = binary
      if self.binary_name_filter:
        binary = self.binary_name_filter(binary)
      symbolized_line = self.symbolize_address(addr, binary, offset)
      if not symbolized_line:
        if original_binary != binary:
          symbolized_line = self.symbolize_address(addr, binary, offset)
      self.print_symbolized_lines(symbolized_line)


if __name__ == '__main__':
  loop = SymbolizationLoop()
  loop.process_stdin()
