import itertools
import functools
from gdb.FrameIterator import FrameIterator
from gdb.command.backtrace import FrameWrapper

"""
source -p /this/script.py

set a breakpoint as usual
then
commands <break#>
taras
end
"""

openers = {}

def report():
    def sum_ls_len(values):
        sum = 0
        files = set()
        for ls in values:
            sum = sum + len(ls)
            for file in ls:
                files.add(file)
        return (sum, list(files))
    def compare(x, y):
        return y[1][0] - x[1][0]
    func_cost = ((key,sum_ls_len(value.values()))
          for (key, value) in openers.items())
    ls = list(func_cost)
    ls.sort(compare)
    for (func, (cost, files)) in ls:
        print("%d %s %s" %(cost, func, ",".join(files)))
        
class SavePrefixCommand (gdb.Command):
  "Prefix command for saving things."

  def __init__ (self):
    super (SavePrefixCommand, self).__init__ ("taras",
                         gdb.COMMAND_SUPPORT,
                         gdb.COMPLETE_NONE, True)

  def register_fopen (self, name, loc, filename):
      global openers
      try:
          ls = openers[name]
      except KeyError:
          ls = {}
          openers[name] = ls
      try:
          filels = ls[loc]
          filels.append(filename)
      except KeyError:
          ls[loc] = [filename]


  def invoke (self, arg, from_tty):
      newest_frame = gdb.selected_thread ().newest_frame ()
      i = itertools.imap (FrameWrapper, FrameIterator (newest_frame))
      filename = None
      if gdb.selected_frame().name() == "open64":
          #yank value out of register for syscalls
          filename = gdb.parse_and_eval("(char*)$rdi").string()

      for foo in i:
          sal = foo.frame.find_sal()
          name = foo.frame.name()
          func = foo.frame.function ()
          if filename == None and func:
              block = func.value
              for sym in block:
                  if not sym.is_argument or sym.name != "filename":
                      continue
                  try:
                      filename = foo.frame.read_var(sym).string()
                  except:
                      pass
          if sal.symtab and sal.symtab.filename:
              fname = sal.symtab.filename
              if fname.find("/mozilla-central/") == -1 or fname.find("nspr") != -1:
                  continue
              loc = fname + ":" + str(sal.line)
              #print([name, foo.block(), loc])
              self.register_fopen(name, loc, filename)
              break;
      gdb.execute("continue")

SavePrefixCommand()