python # GDB dashboard - Modular visual interface for GDB in Python. # # https://github.com/cyrus-and/gdb-dashboard import ast import fcntl import os import re import struct import termios import traceback import math # Common attributes ------------------------------------------------------------ class R(): @staticmethod def attributes(): return { # miscellaneous 'ansi': { 'doc': 'Control the ANSI output of the dashboard.', 'default': True, 'type': bool }, 'syntax_highlighting': { 'doc': """Pygments style to use for syntax highlighting. Using an empty string (or a name not in the list) disables this feature. The list of all the available styles can be obtained with (from GDB itself): python from pygments.styles import get_all_styles as styles python for s in styles(): print(s) """, 'default': 'vim', 'type': str }, # prompt 'prompt': { 'doc': """Command prompt. This value is parsed as a Python format string in which `{status}` is expanded with the substitution of either `prompt_running` or `prompt_not_running` attributes, according to the target program status. The resulting string must be a valid GDB prompt, see the command `python print(gdb.prompt.prompt_help())`""", 'default': '{status}' }, 'prompt_running': { 'doc': """`{status}` when the target program is running. See the `prompt` attribute. This value is parsed as a Python format string in which `{pid}` is expanded with the process identifier of the target program.""", 'default': '\[\e[1;35m\]>>>\[\e[0m\]' }, 'prompt_not_running': { 'doc': '`{status}` when the target program is not running.', 'default': '\[\e[1;30m\]>>>\[\e[0m\]' }, # divider 'divider_fill_char_primary': { 'doc': 'Filler around the label for primary dividers', 'default': '─' }, 'divider_fill_char_secondary': { 'doc': 'Filler around the label for secondary dividers', 'default': '─' }, 'divider_fill_style_primary': { 'doc': 'Style for `divider_fill_char_primary`', 'default': '36' }, 'divider_fill_style_secondary': { 'doc': 'Style for `divider_fill_char_secondary`', 'default': '1;30' }, 'divider_label_style_on_primary': { 'doc': 'Label style for non-empty primary dividers', 'default': '1;33' }, 'divider_label_style_on_secondary': { 'doc': 'Label style for non-empty secondary dividers', 'default': '0' }, 'divider_label_style_off_primary': { 'doc': 'Label style for empty primary dividers', 'default': '33' }, 'divider_label_style_off_secondary': { 'doc': 'Label style for empty secondary dividers', 'default': '1;30' }, 'divider_label_skip': { 'doc': 'Gap between the aligning border and the label.', 'default': 3, 'type': int, 'check': check_ge_zero }, 'divider_label_margin': { 'doc': 'Number of spaces around the label.', 'default': 1, 'type': int, 'check': check_ge_zero }, 'divider_label_align_right': { 'doc': 'Label alignment flag.', 'default': False, 'type': bool }, # common styles 'style_selected_1': { 'default': '1;32' }, 'style_selected_2': { 'default': '32' }, 'style_low': { 'default': '1;30' }, 'style_high': { 'default': '1;37' }, 'style_error': { 'default': '31' } } # Common ----------------------------------------------------------------------- def run(command): return gdb.execute(command, to_string=True) def ansi(string, style): if R.ansi: return '\x1b[{}m{}\x1b[0m'.format(style, string) else: return string def divider(width, label='', primary=False, active=True): if primary: divider_fill_style = R.divider_fill_style_primary divider_fill_char = R.divider_fill_char_primary divider_label_style_on = R.divider_label_style_on_primary divider_label_style_off = R.divider_label_style_off_primary else: divider_fill_style = R.divider_fill_style_secondary divider_fill_char = R.divider_fill_char_secondary divider_label_style_on = R.divider_label_style_on_secondary divider_label_style_off = R.divider_label_style_off_secondary if label: if active: divider_label_style = divider_label_style_on else: divider_label_style = divider_label_style_off skip = R.divider_label_skip margin = R.divider_label_margin before = ansi(divider_fill_char * skip, divider_fill_style) middle = ansi(label, divider_label_style) after_length = width - len(label) - skip - 2 * margin after = ansi(divider_fill_char * after_length, divider_fill_style) if R.divider_label_align_right: before, after = after, before return ''.join([before, ' ' * margin, middle, ' ' * margin, after]) else: return ansi(divider_fill_char * width, divider_fill_style) def check_gt_zero(x): return x > 0 def check_ge_zero(x): return x >= 0 def to_unsigned(value, size=8): # values from GDB can be used transparently but are not suitable for # being printed as unsigned integers, so a conversion is needed mask = (2 ** (size * 8)) - 1 return int(value.cast(gdb.Value(mask).type)) & mask def to_string(value): # attempt to convert an inferior value to string; OK when (Python 3 || # simple ASCII); otherwise (Python 2.7 && not ASCII) encode the string as # utf8 try: value_string = str(value) except UnicodeEncodeError: value_string = unicode(value).encode('utf8') return value_string def format_address(address): pointer_size = gdb.parse_and_eval('$pc').type.sizeof return ('0x{{:0{}x}}').format(pointer_size * 2).format(address) def format_value(value): # format references as referenced values # (TYPE_CODE_RVALUE_REF is not supported by old GDB) if value.type.code in (getattr(gdb, 'TYPE_CODE_REF', None), getattr(gdb, 'TYPE_CODE_RVALUE_REF', None)): try: return to_string(value.referenced_value()) except gdb.MemoryError: return to_string(value) else: try: return to_string(value) except gdb.MemoryError as e: return ansi(e, R.style_error) class Beautifier(): def __init__(self, filename, tab_size=4): self.tab_spaces = ' ' * tab_size self.active = False if not R.ansi: return # attempt to set up Pygments try: from pygments.lexers import get_lexer_for_filename from pygments.formatters import Terminal256Formatter self.formatter = Terminal256Formatter(style=R.syntax_highlighting) self.lexer = get_lexer_for_filename(filename, stripnl=False) self.active = True except ImportError: # Pygments not available pass except pygments.util.ClassNotFound: # no lexer for this file or invalid style pass def process(self, source): # convert tabs anyway source = source.replace('\t', self.tab_spaces) if self.active: import pygments source = pygments.highlight(source, self.lexer, self.formatter) return source.rstrip('\n') # Dashboard -------------------------------------------------------------------- class Dashboard(gdb.Command): """Redisplay the dashboard.""" def __init__(self): gdb.Command.__init__(self, 'dashboard', gdb.COMMAND_USER, gdb.COMPLETE_NONE, True) self.output = None # main terminal # setup subcommands Dashboard.ConfigurationCommand(self) Dashboard.OutputCommand(self) Dashboard.EnabledCommand(self) Dashboard.LayoutCommand(self) # setup style commands Dashboard.StyleCommand(self, 'dashboard', R, R.attributes()) # disabled by default self.enabled = None self.disable() def on_continue(self, _): # try to contain the GDB messages in a specified area unless the # dashboard is printed to a separate file (dashboard -output ...) if self.is_running() and not self.output: width = Dashboard.get_term_width() gdb.write(Dashboard.clear_screen()) gdb.write(divider(width, 'Output/messages', True)) gdb.write('\n') gdb.flush() def on_stop(self, _): if self.is_running(): self.render(clear_screen=False) def on_exit(self, _): if not self.is_running(): return # collect all the outputs outputs = set() outputs.add(self.output) outputs.update(module.output for module in self.modules) outputs.remove(None) # clean the screen and notify to avoid confusion for output in outputs: try: with open(output, 'w') as fs: fs.write(Dashboard.reset_terminal()) fs.write(Dashboard.clear_screen()) fs.write('--- EXITED ---') except: # skip cleanup for invalid outputs pass def enable(self): if self.enabled: return self.enabled = True # setup events gdb.events.cont.connect(self.on_continue) gdb.events.stop.connect(self.on_stop) gdb.events.exited.connect(self.on_exit) def disable(self): if not self.enabled: return self.enabled = False # setup events gdb.events.cont.disconnect(self.on_continue) gdb.events.stop.disconnect(self.on_stop) gdb.events.exited.disconnect(self.on_exit) def load_modules(self, modules): self.modules = [] for module in modules: info = Dashboard.ModuleInfo(self, module) self.modules.append(info) def redisplay(self, style_changed=False): # manually redisplay the dashboard if self.is_running() and self.enabled: self.render(True, style_changed) def inferior_pid(self): return gdb.selected_inferior().pid def is_running(self): return self.inferior_pid() != 0 def render(self, clear_screen, style_changed=False): # fetch module content and info all_disabled = True display_map = dict() for module in self.modules: # fall back to the global value output = module.output or self.output # add the instance or None if disabled if module.enabled: all_disabled = False instance = module.instance else: instance = None display_map.setdefault(output, []).append(instance) # notify the user if the output is empty, on the main terminal if all_disabled: # write the error message width = Dashboard.get_term_width() gdb.write(divider(width, 'Error', True)) gdb.write('\n') if self.modules: gdb.write('No module to display (see `help dashboard`)') else: gdb.write('No module loaded') # write the terminator gdb.write('\n') gdb.write(divider(width, primary=True)) gdb.write('\n') gdb.flush() # continue to allow separate terminals to update # process each display info for output, instances in display_map.items(): try: fs = None # use GDB stream by default if output: fs = open(output, 'w') fd = fs.fileno() # setup the terminal fs.write(Dashboard.hide_cursor()) else: fs = gdb fd = 1 # stdout # get the terminal width (default main terminal if either # the output is not a file) try: width = Dashboard.get_term_width(fd) except: width = Dashboard.get_term_width() # clear the "screen" if requested for the main terminal, # auxiliary terminals are always cleared if fs is not gdb or clear_screen: fs.write(Dashboard.clear_screen()) # show message in separate terminals if all the modules are # disabled if output != self.output and not any(instances): fs.write('--- NO MODULE TO DISPLAY ---\n') continue # process all the modules for that output for n, instance in enumerate(instances, 1): # skip disabled modules if not instance: continue # ask the module to generate the content lines = instance.lines(width, style_changed) # create the divider accordingly div = divider(width, instance.label(), True, lines) # write the data fs.write('\n'.join([div] + lines)) # write the newline for all but last unless main terminal if n != len(instances) or fs is gdb: fs.write('\n') # write the final newline and the terminator only if it is the # main terminal to allow the prompt to display correctly (unless # there are no modules to display) if fs is gdb and not all_disabled: fs.write(divider(width, primary=True)) fs.write('\n') fs.flush() except Exception as e: cause = traceback.format_exc().strip() Dashboard.err('Cannot write the dashboard\n{}'.format(cause)) finally: # don't close gdb stream if fs and fs is not gdb: fs.close() # Utility methods -------------------------------------------------------------- @staticmethod def start(): # initialize the dashboard dashboard = Dashboard() Dashboard.set_custom_prompt(dashboard) # parse Python inits, load modules then parse GDB inits Dashboard.parse_inits(True) modules = Dashboard.get_modules() dashboard.load_modules(modules) Dashboard.parse_inits(False) # GDB overrides run('set pagination off') # enable and display if possible (program running) dashboard.enable() dashboard.redisplay() @staticmethod def get_term_width(fd=1): # defaults to the main terminal # first 2 shorts (4 byte) of struct winsize raw = fcntl.ioctl(fd, termios.TIOCGWINSZ, ' ' * 4) height, width = struct.unpack('hh', raw) return int(width) @staticmethod def set_custom_prompt(dashboard): def custom_prompt(_): # render thread status indicator if dashboard.is_running(): pid = dashboard.inferior_pid() status = R.prompt_running.format(pid=pid) else: status = R.prompt_not_running # build prompt prompt = R.prompt.format(status=status) prompt = gdb.prompt.substitute_prompt(prompt) return prompt + ' ' # force trailing space gdb.prompt_hook = custom_prompt @staticmethod def parse_inits(python): for root, dirs, files in os.walk(os.path.expanduser('~/.gdbinit.d/')): dirs.sort() for init in sorted(files): path = os.path.join(root, init) _, ext = os.path.splitext(path) # either load Python files or GDB if python == (ext == '.py'): gdb.execute('source ' + path) @staticmethod def get_modules(): # scan the scope for modules modules = [] for name in globals(): obj = globals()[name] try: if issubclass(obj, Dashboard.Module): modules.append(obj) except TypeError: continue # sort modules alphabetically modules.sort(key=lambda x: x.__name__) return modules @staticmethod def create_command(name, invoke, doc, is_prefix, complete=None): Class = type('', (gdb.Command,), {'invoke': invoke, '__doc__': doc}) Class(name, gdb.COMMAND_USER, complete or gdb.COMPLETE_NONE, is_prefix) @staticmethod def err(string): print(ansi(string, R.style_error)) @staticmethod def complete(word, candidates): return filter(lambda candidate: candidate.startswith(word), candidates) @staticmethod def parse_arg(arg): # encode unicode GDB command arguments as utf8 in Python 2.7 if type(arg) is not str: arg = arg.encode('utf8') return arg @staticmethod def clear_screen(): # ANSI: move the cursor to top-left corner and clear the screen return '\x1b[H\x1b[J' @staticmethod def hide_cursor(): # ANSI: hide cursor return '\x1b[?25l' @staticmethod def reset_terminal(): # ANSI: reset to initial state return '\x1bc' # Module descriptor ------------------------------------------------------------ class ModuleInfo: def __init__(self, dashboard, module): self.name = module.__name__.lower() # from class to module name self.enabled = True self.output = None # value from the dashboard by default self.instance = module() self.doc = self.instance.__doc__ or '(no documentation)' self.prefix = 'dashboard {}'.format(self.name) # add GDB commands self.add_main_command(dashboard) self.add_output_command(dashboard) self.add_style_command(dashboard) self.add_subcommands(dashboard) def add_main_command(self, dashboard): module = self def invoke(self, arg, from_tty, info=self): arg = Dashboard.parse_arg(arg) if arg == '': info.enabled ^= True if dashboard.is_running(): dashboard.redisplay() else: status = 'enabled' if info.enabled else 'disabled' print('{} module {}'.format(module.name, status)) else: Dashboard.err('Wrong argument "{}"'.format(arg)) doc_brief = 'Configure the {} module.'.format(self.name) doc_extended = 'Toggle the module visibility.' doc = '{}\n{}\n\n{}'.format(doc_brief, doc_extended, self.doc) Dashboard.create_command(self.prefix, invoke, doc, True) def add_output_command(self, dashboard): Dashboard.OutputCommand(dashboard, self.prefix, self) def add_style_command(self, dashboard): if 'attributes' in dir(self.instance): Dashboard.StyleCommand(dashboard, self.prefix, self.instance, self.instance.attributes()) def add_subcommands(self, dashboard): if 'commands' in dir(self.instance): for name, command in self.instance.commands().items(): self.add_subcommand(dashboard, name, command) def add_subcommand(self, dashboard, name, command): action = command['action'] doc = command['doc'] complete = command.get('complete') def invoke(self, arg, from_tty, info=self): arg = Dashboard.parse_arg(arg) if info.enabled: try: action(arg) except Exception as e: Dashboard.err(e) return # don't catch redisplay errors dashboard.redisplay() else: Dashboard.err('Module disabled') prefix = '{} {}'.format(self.prefix, name) Dashboard.create_command(prefix, invoke, doc, False, complete) # GDB commands ----------------------------------------------------------------- def invoke(self, arg, from_tty): arg = Dashboard.parse_arg(arg) # show messages for checks in redisplay if arg != '': Dashboard.err('Wrong argument "{}"'.format(arg)) elif not self.is_running(): Dashboard.err('Is the target program running?') else: self.redisplay() class ConfigurationCommand(gdb.Command): """Dump the dashboard configuration (layout, styles, outputs). With an optional argument the configuration will be written to the specified file.""" def __init__(self, dashboard): gdb.Command.__init__(self, 'dashboard -configuration', gdb.COMMAND_USER, gdb.COMPLETE_FILENAME) self.dashboard = dashboard def invoke(self, arg, from_tty): arg = Dashboard.parse_arg(arg) if arg: with open(os.path.expanduser(arg), 'w') as fs: fs.write('# auto generated by GDB dashboard\n\n') self.dump(fs) self.dump(gdb) def dump(self, fs): # dump layout self.dump_layout(fs) # dump styles self.dump_style(fs, R) for module in self.dashboard.modules: self.dump_style(fs, module.instance, module.prefix) # dump outputs self.dump_output(fs, self.dashboard) for module in self.dashboard.modules: self.dump_output(fs, module, module.prefix) def dump_layout(self, fs): layout = ['dashboard -layout'] for module in self.dashboard.modules: mark = '' if module.enabled else '!' layout.append('{}{}'.format(mark, module.name)) fs.write(' '.join(layout)) fs.write('\n') def dump_style(self, fs, obj, prefix='dashboard'): attributes = getattr(obj, 'attributes', lambda: dict())() for name, attribute in attributes.items(): real_name = attribute.get('name', name) default = attribute.get('default') value = getattr(obj, real_name) if value != default: fs.write('{} -style {} {!r}\n'.format(prefix, name, value)) def dump_output(self, fs, obj, prefix='dashboard'): output = getattr(obj, 'output') if output: fs.write('{} -output {}\n'.format(prefix, output)) class OutputCommand(gdb.Command): """Set the output file/TTY for both the dashboard and modules. The dashboard/module will be written to the specified file, which will be created if it does not exist. If the specified file identifies a terminal then its width will be used to format the dashboard, otherwise falls back to the width of the main GDB terminal. Without argument the dashboard, the output/messages and modules which do not specify the output will be printed on standard output (default). Without argument the module will be printed where the dashboard will be printed.""" def __init__(self, dashboard, prefix=None, obj=None): if not prefix: prefix = 'dashboard' if not obj: obj = dashboard prefix = prefix + ' -output' gdb.Command.__init__(self, prefix, gdb.COMMAND_USER, gdb.COMPLETE_FILENAME) self.dashboard = dashboard self.obj = obj # None means the dashboard itself def invoke(self, arg, from_tty): arg = Dashboard.parse_arg(arg) # display a message in a separate terminal if released (note that # the check if this is the last module to use the output is not # performed since if that's not the case the message will be # overwritten) if self.obj.output: try: with open(self.obj.output, 'w') as fs: fs.write(Dashboard.clear_screen()) fs.write('--- RELEASED ---\n') except: # just do nothing if the file is not writable pass # set or open the output file if arg == '': self.obj.output = None else: self.obj.output = arg # redisplay the dashboard in the new output self.dashboard.redisplay() class EnabledCommand(gdb.Command): """Enable or disable the dashboard [on|off]. The current status is printed if no argument is present.""" def __init__(self, dashboard): gdb.Command.__init__(self, 'dashboard -enabled', gdb.COMMAND_USER) self.dashboard = dashboard def invoke(self, arg, from_tty): arg = Dashboard.parse_arg(arg) if arg == '': status = 'enabled' if self.dashboard.enabled else 'disabled' print('The dashboard is {}'.format(status)) elif arg == 'on': self.dashboard.enable() self.dashboard.redisplay() elif arg == 'off': self.dashboard.disable() else: msg = 'Wrong argument "{}"; expecting "on" or "off"' Dashboard.err(msg.format(arg)) def complete(self, text, word): return Dashboard.complete(word, ['on', 'off']) class LayoutCommand(gdb.Command): """Set or show the dashboard layout. Accepts a space-separated list of directive. Each directive is in the form "[!]". Modules in the list are placed in the dashboard in the same order as they appear and those prefixed by "!" are disabled by default. Omitted modules are hidden and placed at the bottom in alphabetical order. Without arguments the current layout is shown where the first line uses the same form expected by the input while the remaining depict the current status of output files.""" def __init__(self, dashboard): gdb.Command.__init__(self, 'dashboard -layout', gdb.COMMAND_USER) self.dashboard = dashboard def invoke(self, arg, from_tty): arg = Dashboard.parse_arg(arg) directives = str(arg).split() if directives: self.layout(directives) if from_tty and not self.dashboard.is_running(): self.show() else: self.show() def show(self): global_str = 'Global' max_name_len = len(global_str) # print directives modules = [] for module in self.dashboard.modules: max_name_len = max(max_name_len, len(module.name)) mark = '' if module.enabled else '!' modules.append('{}{}'.format(mark, module.name)) print(' '.join(modules)) # print outputs default = '(default)' fmt = '{{:{}s}}{{}}'.format(max_name_len + 2) print(('\n' + fmt + '\n').format(global_str, self.dashboard.output or default)) for module in self.dashboard.modules: style = R.style_high if module.enabled else R.style_low line = fmt.format(module.name, module.output or default) print(ansi(line, style)) def layout(self, directives): modules = self.dashboard.modules # reset visibility for module in modules: module.enabled = False # move and enable the selected modules on top last = 0 n_enabled = 0 for directive in directives: # parse next directive enabled = (directive[0] != '!') name = directive[not enabled:] try: # it may actually start from last, but in this way repeated # modules can be handled transparently and without error todo = enumerate(modules[last:], start=last) index = next(i for i, m in todo if name == m.name) modules[index].enabled = enabled modules.insert(last, modules.pop(index)) last += 1 n_enabled += enabled except StopIteration: def find_module(x): return x.name == name first_part = modules[:last] if len(list(filter(find_module, first_part))) == 0: Dashboard.err('Cannot find module "{}"'.format(name)) else: Dashboard.err('Module "{}" already set'.format(name)) continue # redisplay the dashboard if n_enabled: self.dashboard.redisplay() def complete(self, text, word): all_modules = (m.name for m in self.dashboard.modules) return Dashboard.complete(word, all_modules) class StyleCommand(gdb.Command): """Access the stylable attributes. Without arguments print all the stylable attributes. Subcommands are used to set or print (when the value is omitted) individual attributes.""" def __init__(self, dashboard, prefix, obj, attributes): self.prefix = prefix + ' -style' gdb.Command.__init__(self, self.prefix, gdb.COMMAND_USER, gdb.COMPLETE_NONE, True) self.dashboard = dashboard self.obj = obj self.attributes = attributes self.add_styles() def add_styles(self): this = self for name, attribute in self.attributes.items(): # fetch fields attr_name = attribute.get('name', name) attr_type = attribute.get('type', str) attr_check = attribute.get('check', lambda _: True) attr_default = attribute['default'] # set the default value (coerced to the type) value = attr_type(attr_default) setattr(self.obj, attr_name, value) # create the command def invoke(self, arg, from_tty, name=name, attr_name=attr_name, attr_type=attr_type, attr_check=attr_check): new_value = Dashboard.parse_arg(arg) if new_value == '': # print the current value value = getattr(this.obj, attr_name) print('{} = {!r}'.format(name, value)) else: try: # convert and check the new value parsed = ast.literal_eval(new_value) value = attr_type(parsed) if not attr_check(value): msg = 'Invalid value "{}" for "{}"' raise Exception(msg.format(new_value, name)) except Exception as e: Dashboard.err(e) else: # set and redisplay setattr(this.obj, attr_name, value) this.dashboard.redisplay(True) prefix = self.prefix + ' ' + name doc = attribute.get('doc', 'This style is self-documenting') Dashboard.create_command(prefix, invoke, doc, False) def invoke(self, arg, from_tty): # an argument here means that the provided attribute is invalid if arg: Dashboard.err('Invalid argument "{}"'.format(arg)) return # print all the pairs for name, attribute in self.attributes.items(): attr_name = attribute.get('name', name) value = getattr(self.obj, attr_name) print('{} = {!r}'.format(name, value)) # Base module ------------------------------------------------------------------ # just a tag class Module(): pass # Default modules -------------------------------------------------------------- class Source(Dashboard.Module): """Show the program source code, if available.""" def __init__(self): self.file_name = None self.source_lines = [] self.ts = None self.highlighted = False def label(self): return 'Source' def lines(self, term_width, style_changed): # skip if the current thread is not stopped if not gdb.selected_thread().is_stopped(): return [] # try to fetch the current line (skip if no line information) sal = gdb.selected_frame().find_sal() current_line = sal.line if current_line == 0: return [] # reload the source file if changed file_name = sal.symtab.fullname() ts = None try: ts = os.path.getmtime(file_name) except: pass # delay error check to open() if (style_changed or file_name != self.file_name or # different file name ts and ts > self.ts): # file modified in the meanwhile self.file_name = file_name self.ts = ts try: highlighter = Beautifier(self.file_name, self.tab_size) self.highlighted = highlighter.active with open(self.file_name) as source_file: source = highlighter.process(source_file.read()) self.source_lines = source.split('\n') except Exception as e: msg = 'Cannot display "{}" ({})'.format(self.file_name, e) return [ansi(msg, R.style_error)] # compute the line range start = max(current_line - 1 - self.context, 0) end = min(current_line - 1 + self.context + 1, len(self.source_lines)) # return the source code listing out = [] number_format = '{{:>{}}}'.format(len(str(end))) for number, line in enumerate(self.source_lines[start:end], start + 1): # properly handle UTF-8 source files line = to_string(line) if int(number) == current_line: # the current line has a different style without ANSI if R.ansi: if self.highlighted: line_format = ansi(number_format, R.style_selected_1) + ' {}' else: line_format = ansi(number_format + ' {}', R.style_selected_1) else: # just show a plain text indicator line_format = number_format + '>{}' else: line_format = ansi(number_format, R.style_low) + ' {}' out.append(line_format.format(number, line.rstrip('\n'))) return out def attributes(self): return { 'context': { 'doc': 'Number of context lines.', 'default': 5, 'type': int, 'check': check_ge_zero }, 'tab-size': { 'doc': 'Number of spaces used to display the tab character.', 'default': 4, 'name': 'tab_size', 'type': int, 'check': check_gt_zero } } class Assembly(Dashboard.Module): """Show the disassembled code surrounding the program counter. The instructions constituting the current statement are marked, if available.""" def label(self): return 'Assembly' def lines(self, term_width, style_changed): # skip if the current thread is not stopped if not gdb.selected_thread().is_stopped(): return [] line_info = None frame = gdb.selected_frame() # PC is here disassemble = frame.architecture().disassemble try: # try to fetch the function boundaries using the disassemble command output = run('disassemble').split('\n') start = int(re.split('[ :]', output[1][3:], 1)[0], 16) end = int(re.split('[ :]', output[-3][3:], 1)[0], 16) asm = disassemble(start, end_pc=end) # find the location of the PC pc_index = next(index for index, instr in enumerate(asm) if instr['addr'] == frame.pc()) start = max(pc_index - self.context, 0) end = pc_index + self.context + 1 asm = asm[start:end] # if there are line information then use it, it may be that # line_info is not None but line_info.last is None line_info = gdb.find_pc_line(frame.pc()) line_info = line_info if line_info.last else None except (gdb.error, StopIteration): # if it is not possible (stripped binary or the PC is not present in # the output of `disassemble` as per issue #31) start from PC and # end after twice the context try: asm = disassemble(frame.pc(), count=2 * self.context + 1) except gdb.error as e: msg = '{}'.format(e) return [ansi(msg, R.style_error)] # fetch function start if available func_start = None if self.show_function and frame.name(): try: # it may happen that the frame name is the whole function # declaration, instead of just the name, e.g., 'getkey()', so it # would be treated as a function call by 'gdb.parse_and_eval', # hence the trim, see #87 and #88 value = gdb.parse_and_eval(frame.name().split('(')[0]).address func_start = to_unsigned(value) except gdb.error: pass # e.g., @plt # fetch the assembly flavor and the extension used by Pygments try: flavor = gdb.parameter('disassembly-flavor') except: flavor = None # not always defined (see #36) filename = { 'att': '.s', 'intel': '.asm' }.get(flavor, '.s') # prepare the highlighter highlighter = Beautifier(filename) # compute the maximum offset size if func_start: max_offset = max(len(str(abs(asm[0]['addr'] - func_start))), len(str(abs(asm[-1]['addr'] - func_start)))) # return the machine code max_length = max(instr['length'] for instr in asm) inferior = gdb.selected_inferior() out = [] for index, instr in enumerate(asm): addr = instr['addr'] length = instr['length'] text = instr['asm'] addr_str = format_address(addr) if self.show_opcodes: # fetch and format opcode region = inferior.read_memory(addr, length) opcodes = (' '.join('{:02x}'.format(ord(byte)) for byte in region)) opcodes += (max_length - len(region)) * 3 * ' ' + ' ' else: opcodes = '' # compute the offset if available if self.show_function: if func_start: offset = '{:+d}'.format(addr - func_start) offset = offset.ljust(max_offset + 1) # sign func_info = '{}{}'.format(frame.name(), offset) else: func_info = '?' else: func_info = '' format_string = '{}{}{}{}{}' indicator = ' ' text = ' ' + highlighter.process(text) if addr == frame.pc(): if not R.ansi: indicator = '>' addr_str = ansi(addr_str, R.style_selected_1) indicator = ansi(indicator, R.style_selected_1) opcodes = ansi(opcodes, R.style_selected_1) func_info = ansi(func_info, R.style_selected_1) if not highlighter.active: text = ansi(text, R.style_selected_1) elif line_info and line_info.pc <= addr < line_info.last: if not R.ansi: indicator = ':' addr_str = ansi(addr_str, R.style_selected_2) indicator = ansi(indicator, R.style_selected_2) opcodes = ansi(opcodes, R.style_selected_2) func_info = ansi(func_info, R.style_selected_2) if not highlighter.active: text = ansi(text, R.style_selected_2) else: addr_str = ansi(addr_str, R.style_low) func_info = ansi(func_info, R.style_low) out.append(format_string.format(addr_str, indicator, opcodes, func_info, text)) return out def attributes(self): return { 'context': { 'doc': 'Number of context instructions.', 'default': 3, 'type': int, 'check': check_ge_zero }, 'opcodes': { 'doc': 'Opcodes visibility flag.', 'default': False, 'name': 'show_opcodes', 'type': bool }, 'function': { 'doc': 'Function information visibility flag.', 'default': True, 'name': 'show_function', 'type': bool } } class Stack(Dashboard.Module): """Show the current stack trace including the function name and the file location, if available. Optionally list the frame arguments and locals too.""" def label(self): return 'Stack' def lines(self, term_width, style_changed): # skip if the current thread is not stopped if not gdb.selected_thread().is_stopped(): return [] # find the selected frame (i.e., the first to display) selected_index = 0 frame = gdb.newest_frame() while frame: if frame == gdb.selected_frame(): break frame = frame.older() selected_index += 1 # format up to "limit" frames frames = [] number = selected_index more = False while frame: # the first is the selected one selected = (len(frames) == 0) # fetch frame info style = R.style_selected_1 if selected else R.style_selected_2 frame_id = ansi(str(number), style) info = Stack.get_pc_line(frame, style) frame_lines = [] frame_lines.append('[{}] {}'.format(frame_id, info)) # fetch frame arguments and locals decorator = gdb.FrameDecorator.FrameDecorator(frame) separator = ansi(', ', R.style_low) strip_newlines = re.compile(r'$\s*', re.MULTILINE) if self.show_arguments: def prefix(line): return Stack.format_line('arg', line) frame_args = decorator.frame_args() args_lines = Stack.fetch_frame_info(frame, frame_args) if args_lines: if self.compact: args_line = separator.join(args_lines) args_line = strip_newlines.sub('', args_line) single_line = prefix(args_line) frame_lines.append(single_line) else: frame_lines.extend(map(prefix, args_lines)) else: frame_lines.append(ansi('(no arguments)', R.style_low)) if self.show_locals: def prefix(line): return Stack.format_line('loc', line) frame_locals = decorator.frame_locals() locals_lines = Stack.fetch_frame_info(frame, frame_locals) if locals_lines: if self.compact: locals_line = separator.join(locals_lines) locals_line = strip_newlines.sub('', locals_line) single_line = prefix(locals_line) frame_lines.append(single_line) else: frame_lines.extend(map(prefix, locals_lines)) else: frame_lines.append(ansi('(no locals)', R.style_low)) # add frame frames.append(frame_lines) # next frame = frame.older() number += 1 # check finished according to the limit if self.limit and len(frames) == self.limit: # more frames to show but limited if frame: more = True break # format the output lines = [] for frame_lines in frames: lines.extend(frame_lines) # add the placeholder if more: lines.append('[{}]'.format(ansi('+', R.style_selected_2))) return lines @staticmethod def format_line(prefix, line): prefix = ansi(prefix, R.style_low) return '{} {}'.format(prefix, line) @staticmethod def fetch_frame_info(frame, data): lines = [] for elem in data or []: name = elem.sym equal = ansi('=', R.style_low) value = format_value(elem.sym.value(frame)) lines.append('{} {} {}'.format(name, equal, value)) return lines @staticmethod def get_pc_line(frame, style): frame_pc = ansi(format_address(frame.pc()), style) info = 'from {}'.format(frame_pc) if frame.name(): frame_name = ansi(frame.name(), style) try: # try to compute the offset relative to the current function (it # may happen that the frame name is the whole function # declaration, instead of just the name, e.g., 'getkey()', so it # would be treated as a function call by 'gdb.parse_and_eval', # hence the trim, see #87 and #88) value = gdb.parse_and_eval(frame.name().split('(')[0]).address # it can be None even if it is part of the "stack" (C++) if value: func_start = to_unsigned(value) offset = frame.pc() - func_start frame_name += '+' + ansi(str(offset), style) except gdb.error: pass # e.g., @plt info += ' in {}'.format(frame_name) sal = frame.find_sal() if sal.symtab: file_name = ansi(sal.symtab.filename, style) file_line = ansi(str(sal.line), style) info += ' at {}:{}'.format(file_name, file_line) return info def attributes(self): return { 'limit': { 'doc': 'Maximum number of displayed frames (0 means no limit).', 'default': 2, 'type': int, 'check': check_ge_zero }, 'arguments': { 'doc': 'Frame arguments visibility flag.', 'default': True, 'name': 'show_arguments', 'type': bool }, 'locals': { 'doc': 'Frame locals visibility flag.', 'default': False, 'name': 'show_locals', 'type': bool }, 'compact': { 'doc': 'Single-line display flag.', 'default': False, 'type': bool } } class History(Dashboard.Module): """List the last entries of the value history.""" def label(self): return 'History' def lines(self, term_width, style_changed): out = [] # fetch last entries for i in range(-self.limit + 1, 1): try: value = format_value(gdb.history(i)) value_id = ansi('$${}', R.style_low).format(abs(i)) line = '{} = {}'.format(value_id, value) out.append(line) except gdb.error: continue return out def attributes(self): return { 'limit': { 'doc': 'Maximum number of values to show.', 'default': 3, 'type': int, 'check': check_gt_zero } } class Memory(Dashboard.Module): """Allow to inspect memory regions.""" @staticmethod def format_byte(byte): # `type(byte) is bytes` in Python 3 if byte.isspace(): return ' ' elif 0x20 < ord(byte) < 0x7e: return chr(ord(byte)) else: return '.' @staticmethod def parse_as_address(expression): value = gdb.parse_and_eval(expression) return to_unsigned(value) def __init__(self): self.row_length = 16 self.table = {} def format_memory(self, start, memory): out = [] for i in range(0, len(memory), self.row_length): region = memory[i:i + self.row_length] pad = self.row_length - len(region) address = format_address(start + i) hexa = (' '.join('{:02x}'.format(ord(byte)) for byte in region)) text = (''.join(Memory.format_byte(byte) for byte in region)) out.append('{} {}{} {}{}'.format(ansi(address, R.style_low), hexa, ansi(pad * ' --', R.style_low), ansi(text, R.style_high), ansi(pad * '.', R.style_low))) return out def label(self): return 'Memory' def lines(self, term_width, style_changed): out = [] inferior = gdb.selected_inferior() for address, length in sorted(self.table.items()): try: memory = inferior.read_memory(address, length) out.extend(self.format_memory(address, memory)) except gdb.error: msg = 'Cannot access {} bytes starting at {}' msg = msg.format(length, format_address(address)) out.append(ansi(msg, R.style_error)) out.append(divider(term_width)) # drop last divider if out: del out[-1] return out def watch(self, arg): if arg: address, _, length = arg.partition(' ') address = Memory.parse_as_address(address) if length: length = Memory.parse_as_address(length) else: length = self.row_length self.table[address] = length else: raise Exception('Specify an address') def unwatch(self, arg): if arg: try: del self.table[Memory.parse_as_address(arg)] except KeyError: raise Exception('Memory region not watched') else: raise Exception('Specify an address') def clear(self, arg): self.table.clear() def commands(self): return { 'watch': { 'action': self.watch, 'doc': 'Watch a memory region by address and length.\n' 'The length defaults to 16 byte.', 'complete': gdb.COMPLETE_EXPRESSION }, 'unwatch': { 'action': self.unwatch, 'doc': 'Stop watching a memory region by address.', 'complete': gdb.COMPLETE_EXPRESSION }, 'clear': { 'action': self.clear, 'doc': 'Clear all the watched regions.' } } class Registers(Dashboard.Module): """Show the CPU registers and their values.""" def __init__(self): self.table = {} def label(self): return 'Registers' def lines(self, term_width, style_changed): # skip if the current thread is not stopped if not gdb.selected_thread().is_stopped(): return [] # fetch registers status registers = [] for reg_info in run('info registers').strip().split('\n'): # fetch register and update the table name = reg_info.split(None, 1)[0] # Exclude registers with a dot '.' or parse_and_eval() will fail if '.' in name: continue value = gdb.parse_and_eval('${}'.format(name)) string_value = Registers.format_value(value) changed = self.table and (self.table.get(name, '') != string_value) self.table[name] = string_value registers.append((name, string_value, changed)) # split registers in rows and columns, each column is composed of name, # space, value and another trailing space which is skipped in the last # column (hence term_width + 1) max_name = max(len(name) for name, _, _ in registers) max_value = max(len(value) for _, value, _ in registers) max_width = max_name + max_value + 2 per_line = int((term_width + 1) / max_width) or 1 # redistribute extra space among columns extra = int((term_width + 1 - max_width * per_line) / per_line) if per_line == 1: # center when there is only one column max_name += int(extra / 2) max_value += int(extra / 2) else: max_value += extra # format registers info partial = [] for name, value, changed in registers: styled_name = ansi(name.rjust(max_name), R.style_low) value_style = R.style_selected_1 if changed else '' styled_value = ansi(value.ljust(max_value), value_style) partial.append(styled_name + ' ' + styled_value) out = [] if self.column_major: num_lines = int(math.ceil(float(len(partial)) / per_line)) for i in range(num_lines): line = ' '.join(partial[i:len(partial):num_lines]).rstrip() real_n_col = math.ceil(float(len(partial)) / num_lines) line = ' ' * int((per_line - real_n_col) * max_width / 2) + line out.append(line) else: for i in range(0, len(partial), per_line): out.append(' '.join(partial[i:i + per_line]).rstrip()) return out def attributes(self): return { 'column-major': { 'doc': 'Whether to show registers in columns instead of rows.', 'default': False, 'name': 'column_major', 'type': bool } } @staticmethod def format_value(value): try: if value.type.code in [gdb.TYPE_CODE_INT, gdb.TYPE_CODE_PTR]: int_value = to_unsigned(value, value.type.sizeof) value_format = '0x{{:0{}x}}'.format(2 * value.type.sizeof) return value_format.format(int_value) except (gdb.error, ValueError): # convert to unsigned but preserve code and flags information pass return str(value) class Threads(Dashboard.Module): """List the currently available threads.""" def label(self): return 'Threads' def lines(self, term_width, style_changed): out = [] selected_thread = gdb.selected_thread() # do not restore the selected frame if the thread is not stopped restore_frame = gdb.selected_thread().is_stopped() if restore_frame: selected_frame = gdb.selected_frame() for thread in gdb.Inferior.threads(gdb.selected_inferior()): # skip running threads if requested if self.skip_running and thread.is_running(): continue is_selected = (thread.ptid == selected_thread.ptid) style = R.style_selected_1 if is_selected else R.style_selected_2 number = ansi(str(thread.num), style) tid = ansi(str(thread.ptid[1] or thread.ptid[2]), style) info = '[{}] id {}'.format(number, tid) if thread.name: info += ' name {}'.format(ansi(thread.name, style)) # switch thread to fetch info (unless is running in non-stop mode) try: thread.switch() frame = gdb.newest_frame() info += ' ' + Stack.get_pc_line(frame, style) except gdb.error: info += ' (running)' out.append(info) # restore thread and frame selected_thread.switch() if restore_frame: selected_frame.select() return out def attributes(self): return { 'skip-running': { 'doc': 'Skip running threads.', 'default': False, 'name': 'skip_running', 'type': bool } } class Expressions(Dashboard.Module): """Watch user expressions.""" def __init__(self): self.number = 1 self.table = {} def label(self): return 'Expressions' def lines(self, term_width, style_changed): out = [] for number, expression in sorted(self.table.items()): try: value = format_value(gdb.parse_and_eval(expression)) except gdb.error as e: value = ansi(e, R.style_error) number = ansi(number, R.style_selected_2) expression = ansi(expression, R.style_low) out.append('[{}] {} = {}'.format(number, expression, value)) return out def watch(self, arg): if arg: self.table[self.number] = arg self.number += 1 else: raise Exception('Specify an expression') def unwatch(self, arg): if arg: try: del self.table[int(arg)] except: raise Exception('Expression not watched') else: raise Exception('Specify an identifier') def clear(self, arg): self.table.clear() def commands(self): return { 'watch': { 'action': self.watch, 'doc': 'Watch an expression.', 'complete': gdb.COMPLETE_EXPRESSION }, 'unwatch': { 'action': self.unwatch, 'doc': 'Stop watching an expression by id.', 'complete': gdb.COMPLETE_EXPRESSION }, 'clear': { 'action': self.clear, 'doc': 'Clear all the watched expressions.' } } # XXX traceback line numbers in this Python block must be increased by 1 end # Better GDB defaults ---------------------------------------------------------- set history save set verbose off set print pretty on set print array off set print array-indexes on set python print-stack full # Start ------------------------------------------------------------------------ python Dashboard.start() # ------------------------------------------------------------------------------ # Copyright (c) 2015-2017 Andrea Cardaci # # Permission is hereby granted, free of charge, to any person obtaining a copy # of this software and associated documentation files (the "Software"), to deal # in the Software without restriction, including without limitation the rights # to use, copy, modify, merge, publish, distribute, sublicense, and/or sell # copies of the Software, and to permit persons to whom the Software is # furnished to do so, subject to the following conditions: # # The above copyright notice and this permission notice shall be included in all # copies or substantial portions of the Software. # # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE # AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE # SOFTWARE. # ------------------------------------------------------------------------------ # vim: filetype=python # Local Variables: # mode: python # End: