escargot/tools/debugger/debugger.py

#!/usr/bin/env python3

# Copyright 2015-present Samsung Electronics Co., Ltd.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

from __future__ import print_function
from cmd import Cmd
from pprint import pprint
import math
import socket
import sys
import logging
import time
import debugger_core

from debugger_websocket import WebSocket
from debugger_tcp import TcpSocket

def write(string):
    print(string, end='')

class DebuggerPrompt(Cmd):
    # pylint: disable=too-many-instance-attributes,too-many-arguments
    def __init__(self, debugger):
        Cmd.__init__(self)
        self.debugger = debugger
        self.stop = False
        self.quit = False

    def precmd(self, line):
        self.stop = False
        if self.debugger.non_interactive:
            print("%s" % line)
        return line

    def postcmd(self, stop, line):
        return self.stop

    def do_quit(self, _):
        """ Exit debugger """
        self.debugger.quit()
        self.quit = True
        self.stop = True

    def do_EOF(self, _):
        """ Exit Escargot debugger """
        print("Unexpected end of input. Connection closed.")
        self.debugger.quit()
        self.quit = True
        self.stop = True

    def do_display(self, args):
        """ Toggle source code display after breakpoints """
        if args:
            line_num = src_check_args(args)
            if line_num >= 0:
                self.debugger.display = line_num
        else:
            print("Non-negative integer number expected, 0 turns off this function")

    def do_watch(self, args):
        """ Add value to watched values display after breakpoints """
        if not args:
            write("Error: Argument expected\n")
        else:
            write(self.debugger.set_watch(args))
    do_w = do_watch

    def do_print_watches(self, _):
        self.debugger.print_watches()
    do_pw = do_print_watches

    def do_watches(self, _):
        self.debugger.list_watches()
    do_list_watches = do_watches
    do_lw = do_watches

    def do_break(self, args):
        """ Insert breakpoints on the given lines or functions """
        if not args:
            write("Error: Argument expected\n")
        else:
            write(self.debugger.set_break(args))
    do_b = do_break

    def do_list(self, _):
        """ Lists the available breakpoints """
        write(self.debugger.breakpoint_list())

    def do_delete(self, args):
        """ Delete the given breakpoint, use 'delete all|active|pending' to clear all the given breakpoints """
        write(self.debugger.delete(args))

    def do_delete_watch(self, args):
        """ Delete the given watch """
        write(self.debugger.delete_watch(args))

    def do_continue(self, _):
        """ Continue execution """
        self.debugger.do_continue()
        self.stop = True
        if not self.debugger.non_interactive:
            print("Press enter to stop JavaScript execution.")
    do_c = do_continue

    def do_step(self, _):
        """ Next breakpoint, step into functions """
        self.debugger.step()
        self.stop = True
    do_s = do_step

    def do_next(self, args):
        """ Next breakpoint in the same context """
        self.stop = True
        if not args:
            args = 0
            self.debugger.next()
            return

        try:
            args = int(args)
            if args <= 0:
                raise ValueError(args)

            while args > 0:
                self.debugger.next()
                time.sleep(0.1)

                while True:
                    result = self.debugger.process_messages()
                    res_type = result.get_type()

                    if res_type == result.END:
                        self.quit = True
                        return
                    elif res_type == result.TEXT:
                        write(result.get_text())
                    elif res_type == result.PROMPT:
                        break

                args -= 1
        except ValueError as val_errno:
            print("Error: expected a positive integer: %s" % val_errno)
    do_n = do_next

    def do_finish(self, _):
        """ Continue running until the current function returns """
        self.debugger.finish()
        self.stop = True
    do_f = do_finish

    def do_src(self, args):
        """ Get current source code """
        if args:
            line_num = src_check_args(args)
            if line_num >= 0:
                write(self.debugger.print_source(line_num, 0))
        else:
            write(self.debugger.print_source(0, 0))
    do_source = do_src

    def do_scroll(self, _):
        """ Scroll the source up or down """
        while True:
            key = sys.stdin.readline()
            if key == 'w\n':
                _scroll_direction(self.debugger, "up")
            elif key == 's\n':
                _scroll_direction(self.debugger, "down")
            elif key == 'q\n':
                break
            else:
                print("Invalid key")

    def do_eval(self, args):
        """ Evaluate JavaScript source code """
        self.debugger.eval(args)
        self.stop = True
    do_e = do_eval
    do_p = do_eval
    do_print = do_eval

    def do_backtrace(self, args):
        """ Get backtrace data from debugger """
        write(self.debugger.backtrace(args))
        self.stop = True
    do_bt = do_backtrace

    def do_take_snapshot(self, args):
        """ Save heap snapshot to a .snapshot file in the escargot binary's folder """
        file_name = self.debugger._send_take_snapshot()
        print("Took heap snapshot as \'" + file_name.decode('utf-8')[1:] + "\'!")
        self.stop = True

    def do_scope(self, args):
        """ Get lexical environment chain """
        self.debugger.scope_chain(args)
        self.stop = True

    def do_variables(self, args):
        """ Get scope variables """
        write(self.debugger.scope_variables(args))
        self.stop = True

    def do_object(self, args):
        """ Get object by index """
        if not args:
            write("Error: Argument expected")
        else:
            write(self.debugger.object(args))
        self.stop = True

    def do_dump(self, args):
        """ Dump all of the debugger data """
        if args:
            print("Error: No argument expected")
        else:
            pprint(self.debugger.function_list)

    def do_restart(self, args):
        """ Restart current debugging from the start of the file """
        self.debugger.send_restart()
        self.debugger.step()
        self.stop = True
    do_re = do_restart

def _scroll_direction(debugger, direction):
    """ Helper function for do_scroll """
    debugger.src_offset_diff = int(max(math.floor(debugger.display / 3), 1))
    if direction == "up":
        debugger.src_offset -= debugger.src_offset_diff
    else:
        debugger.src_offset += debugger.src_offset_diff
    print(debugger.print_source(debugger.display, debugger.src_offset)['value'])


def src_check_args(args):
    try:
        line_num = int(args)
        if line_num < 0:
            print("Error: Non-negative integer number expected")
            return -1

        return line_num
    except ValueError as val_errno:
        print("Error: Non-negative integer number expected: %s" % (val_errno))
        return -1


# pylint: disable=too-many-branches,too-many-locals,too-many-statements,redefined-variable-type
def main():
    args = debugger_core.arguments_parse()

    tranport = TcpSocket(args.address)
    protocol = WebSocket(tranport)
    debugger = debugger_core.Debugger(protocol)

    debugger.non_interactive = args.non_interactive

    logging.debug("Connected to Escargot")

    prompt = DebuggerPrompt(debugger)
    prompt.prompt = "(escargot-debugger) "

    if args.color:
        debugger.set_colors()

    if args.display:
        debugger.display = args.display
        prompt.do_display(args.display)
    else:
        prompt.stop = False

    if args.client_source:
        debugger.store_client_sources(args.client_source)

    if args.wait_before_exit:
        debugger.set_wait_exit(args.wait_before_exit)

    if args.command:
        commands = args.command[0].split(";")
        i = 0
        while i < len(commands):
            result = debugger.process_messages()
            res_type = result.get_type()

            if res_type == result.END:
                return
            elif res_type == result.PROMPT:
                write(commands[i] + "\n")
                prompt.onecmd(commands[i] + "\n")
                i += 1
            elif res_type == result.TEXT:
                write(result.get_text())
            continue

    while True:
        if prompt.quit:
            break

        result = debugger.process_messages()
        res_type = result.get_type()

        if res_type == result.END:
            break
        elif res_type == result.PROMPT:
            prompt.cmdloop()
        elif res_type == result.TEXT:
            write(result.get_text())
        continue


if __name__ == "__main__":
    try:
        main()
        print("Connection closed.")
        sys.exit(0)
    except socket.error as error_msg:
        ERRNO = error_msg.errno
        MSG = str(error_msg)
        if ERRNO == 111:
            sys.exit("Failed to connect to the Escargot debugger.")
        elif ERRNO == 32 or ERRNO == 104:
            sys.exit("Connection closed.")
        else:
            sys.exit("Failed to connect to the Escargot debugger.\nError: %s" % (MSG))