Source code for terminal

#
#       Copyright 2011 Liftoff Software Corporation
#

# Meta
__version__ = '0.9'
__license__ = "AGPLv3 or Proprietary (see LICENSE.txt)"
__version_info__ = (0, 9)
__author__ = 'Dan McDougall <daniel.mcdougall@liftoffsoftware.com>'

__doc__ = """\
About This Module
=================
This crux of this module is the Terminal class which is a pure-Python
implementation of a quintessential Unix-style terminal emulator.  It actually
does its best to emulate an xterm.  This means it supports the majority of the
relevant portions of ECMA-48.  This includes support for emulating varous VT-*
terminal types as well as the "linux" terminal type.

The Terminal class's emulation support is not complete but it should suffice for
most terminal emulation needs.  If additional support for certain escape
sequences or modes are required please feel free to provide a patch or to simply
ask for something to be added.

Note that Terminal was written from scratch in order to be as fast as possible.
Comments have been placed where different implementations/development patterns
have been tried and ultimately failed to provide speed improvements.  Any and
all suggestions or patches to improve speed (or emulation support) are welcome!

Supported Emulation Types
-------------------------
Without any special mode settings or parameters, Terminal should be able to
support most applications under the following terminal types (e.g.
"export TERM=<terminal type>"):

 * xterm (the most important one)
 * ECMA-48/ANSI X3.64
 * Nearly all the VT-* types:  VT-52, VT-100, VT-220, VT-320, VT-420, and VT-520
 * Linux console ("linux")

What Terminal Doesn't Do
------------------------
The Terminal class is meant to emulate the display portion of a given terminal.
It does not translate keystrokes into escape sequences or special control
codes--you'll have to take care of that in your application (or at the
client-side like Gate One).  It does, however, keep track of many
keystroke-specific modes of operation such as Application Cursor Keys and the G0
and G1 charset modes *with* callbacks that can be used to notify your
application when something changes.

Special Considerations
----------------------
Many methods inside Terminal start with an underscore.  This was done to
indicate that such methods shouldn't be called directly (from a program that
imported the module).  If it was thought that a situation might arise where a
method could be used externally by a controlling program, the underscore was
omitted.

Asynchronous Use
----------------
To support asynchronous usage (and make everything faster), Terminal was written
to support extensive callbacks that are called when certain events are
encountered.  Here are the events and their callbacks:

============================    ========================================================================
Callback                        Called when...
============================    ========================================================================
Terminal.CALLBACK_SCROLL_UP     The terminal is scrolled up (back).
Terminal.CALLBACK_CHANGED       The screen is changed/updated.
Terminal.CALLBACK_CURSOR_POS    The cursor position changes.
Terminal.CALLBACK_DSR           A Device Status Report (DSR) is requested (via the DSR escape sequence).
Terminal.CALLBACK_TITLE         The terminal title changes (xterm-style)
Terminal.CALLBACK_BELL          The bell character (^G) is encountered.
Terminal.CALLBACK_OPT           The special optional escape sequence is encountered.
Terminal.CALLBACK_MODE          The terminal mode setting changes (e.g. use alternate screen buffer).
============================    ========================================================================

Note that Terminal.CALLBACK_DSR is special in that it in most cases it will be called with arguments.  See the code for examples of how and when this happens.

Also, in most cases it is unwise to override Terminal.CALLBACK_MODE since this method is primarily meant for internal use within the Terminal class.

Using Terminal
--------------
Gate One makes extensive use of the Terminal class and its callbacks.  So that's
a great place to look for specific examples (gateone.py and termio.py,
specifically).  Having said that, implementing Terminal is pretty
straightforward::

    >>> import terminal
    >>> term = terminal.Terminal(24, 80)
    >>> term.write("This text will be written to the terminal screen.")
    >>> term.dump()
    [u'This text will be written to the terminal screen.                               ',
    <snip>
    u'                                                                                ']

Here's an example with some basic callbacks:

    >>> def mycallback():
    ...     "This will be called whenever the screen changes."
    ...     print("Screen update! Perfect time to dump the terminal screen.")
    ...     print(term.dump()[0]) # Only need to see the top line for this demo =)
    ...     print("Just dumped the screen.")
    >>> import terminal
    >>> term = terminal.Terminal(24, 80)
    >>> term.callbacks[term.CALLBACK_CHANGED] = mycallback
    >>> term.write("This should result in mycallback() being called")
    Screen update! Perfect time to dump the terminal screen.
    This should result in mycallback() being called
    Just dumped the screen.

.. note:: In testing Gate One it was determined that it is faster to perform the conversion of a terminal screen to HTML on the server side than it is on the client side (via JavaScript anyway).

About The Scrollback Bufffer
----------------------------
The Terminal class implements a scrollback buffer.  Here's how it works:
Whenever a scroll_up() event occurs, the line (or lines) that will be removed
from the top of the screen will be placed into Terminal.scrollback_buf.  Then,
whenever dump_html() is called, the scrollback buffer will be returned along
with the screen output and reset to an empty state.

Why do this?  In the event that a very large write() occurs (e.g. 'ps aux'), it
gives the controlling program the ability to capture what went past the screen
without some fancy tracking logic surrounding Terminal.write().

More information about how this works can be had by looking at the dump_html()
function itself.

.. note:: There's more than one function that empties Terminal.scrollback_buf when called.  You'll just have to have a look around =)

Class Docstrings
================
"""

# Imports
import re, time, logging
from collections import defaultdict
from itertools import imap, izip, count
import copy

# Globals
# These are for HTML output:
RENDITION_CLASSES = defaultdict(lambda: None, {
    0: 'reset', # Special: Return everything to defaults
    1: 'bold',
    2: 'dim',
    3: 'italic',
    4: 'underline',
    5: 'blink',
    6: 'fastblink',
    7: 'reverse',
    8: 'hidden',
    9: 'strikethrough',
    10: 'resetfont', # NOTE: The font renditions don't do anything right now
    11: 'font11', # Mostly because I have no idea what they are supposed to look
    12: 'font12', # like.
    13: 'font13',
    14: 'font14',
    15: 'font15',
    16: 'font16',
    17: 'font17',
    18: 'font18',
    19: 'font19',
    20: 'fraktur',
    21: 'boldreset',
    22: 'dimreset',
    23: 'italicreset',
    24: 'underlinereset',
    27: 'reversereset',
    28: 'hiddenreset',
    29: 'strikethroughreset',
    30: 'f0',
    31: 'f1',
    32: 'f2',
    33: 'f3',
    34: 'f4',
    35: 'f5',
    36: 'f6',
    37: 'f7',
    39: 'foregroundreset', # Special: Set FG to default
    40: 'b0',
    41: 'b1',
    42: 'b2',
    43: 'b3',
    44: 'b4',
    45: 'b5',
    46: 'b6',
    47: 'b7',
    49: 'backgroundreset', # Special: Set BG to default
    51: 'frame',
    52: 'encircle',
    53: 'overline',
    60: 'rightline',
    61: 'rightdoubleline',
    62: 'leftline',
    63: 'leftdoubleline'
})

# TODO List:
#
#   * Needs tests!
#   * Figure out how to handle programs like htop that position the cursor without following up with proper rendition reset sequences.

class Terminal(object):
[docs] """ Terminal controller class. """ ASCII_NUL = 0 # Null ASCII_BEL = 7 # Bell (BEL) ASCII_BS = 8 # Backspace ASCII_HT = 9 # Horizontal Tab ASCII_LF = 10 # Line Feed ASCII_VT = 11 # Vertical Tab ASCII_FF = 12 # Form Feed ASCII_CR = 13 # Carriage Return ASCII_XON = 17 # Resume Transmission ASCII_XOFF = 19 # Stop Transmission or Ignore Characters ASCII_CAN = 24 # Cancel Escape Sequence ASCII_SUB = 26 # Substitute: Cancel Escape Sequence and replace with ? ASCII_ESC = 27 # Escape ASCII_CSI = 155 # Control Sequence Introducer (that nothing uses) ASCII_HTS = 210 # Horizontal Tab Stop (HTS) charsets = {'0': { # Line drawing mode 95: u' ', 96: u'◆', 97: u'▒', 98: u'\t', 99: u'\x0c', 100: u'\r', 101: u'\n', 102: u'°', 103: u'±', 104: u'\n', 105: u'\x0b', 106: u'┘', 107: u'┐', 108: u'┌', 109: u'└', 110: u'┼', 111: u'⎺', # All these bars and not a drink! 112: u'⎻', 113: u'─', 114: u'⎼', 115: u'⎽', 116: u'├', 117: u'┤', 118: u'┴', 119: u'┬', 120: u'│', 121: u'≤', 122: u'≥', 123: u'π', 124: u'≠', 125: u'£', 126: u'·' # Centered dot--who comes up with this stuff?!? } } CALLBACK_SCROLL_UP = 1 # Called after a scroll up event (new line) CALLBACK_CHANGED = 2 # Called after the screen is updated CALLBACK_CURSOR_POS = 3 # Called after the cursor position is updated # <waives hand in air> You are not concerned with the number 4 CALLBACK_DSR = 5 # Called when a DSR requires a response # NOTE: CALLBACK_DSR must accept 'response' as either the first argument or # as a keyword argument. CALLBACK_TITLE = 6 # Called when the terminal sets the window title CALLBACK_BELL = 7 # Called after ASCII_BEL is encountered. CALLBACK_OPT = 8 # Called when we encounter the optional ESC sequence # NOTE: CALLBACK_OPT must accept 'chars' as either the first argument or as # a keyword argument. CALLBACK_MODE = 9 # Called when the terminal mode changes (e.g. DECCKM) RE_CSI_ESC_SEQ = re.compile(r'\x1B\[([?A-Za-z0-9;@:\!]*)([A-Za-z@_])') RE_ESC_SEQ = re.compile(r'\x1b(.*\x1b\\|[ABCDEFGHIJKLMNOQRSTUVWXYZa-z0-9=]|[()# %*+].)') RE_TITLE_SEQ = re.compile(r'\x1b\][0-2]\;(.*)(\x07|\x1b\\)') # The below regex is used to match our optional (non-standard) handler RE_OPT_SEQ = re.compile(r'\x1b\]_\;(.*)(\x07|\x1b\\)') RE_NUMBERS = re.compile('\d*') # Matches any number def __init__(self, rows=24, cols=80): self.cols = cols self.rows = rows self.scrollback_buf = [] self.scrollback_renditions = [] self.title = "Gate One" self.ignore = False self.local_echo = True self.esc_buffer = '' # For holding escape sequences as they're typed. self.prev_esc_buffer = '' # Special: So we can differentiate between # certain circumstances. self.show_cursor = True self.rendition_set = False self.init_screen() self.init_renditions() self.G0_charset = 'B' self.G1_charset = 'B' # Set the default window margins self.top_margin, self.bottom_margin = 0, self.rows - 1 self.specials = { self.ASCII_NUL: self.__ignore, self.ASCII_BEL: self._bell, self.ASCII_BS: self._backspace, self.ASCII_HT: self._horizontal_tab, self.ASCII_LF: self._linefeed, self.ASCII_VT: self._linefeed, self.ASCII_FF: self._linefeed, self.ASCII_CR: self._carriage_return, self.ASCII_XON: self._xon, self.ASCII_CAN: self._cancel_esc_sequence, self.ASCII_XOFF: self._xoff, self.ASCII_ESC: self._sub_esc_sequence, self.ASCII_ESC: self._escape, self.ASCII_CSI: self._set_rendition, } # TODO: Finish these: self.esc_handlers = { # TODO: Make a different set of these for each respective emulation mode (VT-52, VT-100, VT-200, etc etc) '#': self._set_line_params, # Varies '\\': self._string_terminator, # ST 'c': self.clear_screen, # Reset terminal 'D': self.__ignore, # Move/scroll window up one line IND 'M': self._reverse_linefeed, # Move/scroll window down one line RI 'E': self._next_line, # Move to next line NEL 'F': self.__ignore, # Enter Graphics Mode 'G': self._next_line, # Exit Graphics Mode '6': self._dsr_get_cursor_position, # Get cursor position DSR '7': self.save_cursor_position, # Save cursor position and attributes DECSC '8': self.restore_cursor_position, # Restore cursor position and attributes DECSC 'H': self._set_tabstop, # Set a tab at the current column HTS 'I': self._reverse_linefeed, '(': self.set_G0_charset, # Designate G0 Character Set ')': self.set_G1_charset, # Designate G1 Character Set 'N': self.__ignore, # Set single shift 2 SS2 'O': self.__ignore, # Set single shift 3 SS3 '5': self._device_status_report, # Request: Device status report DSR '0': self.__ignore, # Response: terminal is OK DSR 'P': self._dcs_handler, # Device Control String DCS '=': self.__ignore, # Application Keypad DECPAM '>': self.__ignore, # Exit alternate keypad mode '<': self.__ignore, # Exit VT-52 mode } self.csi_handlers = { 'A': self.cursor_up, 'B': self.cursor_down, 'C': self.cursor_right, 'D': self.cursor_left, 'E': self.cursor_next_line, 'F': self.cursor_previous_line, 'G': self.cursor_horizontal_absolute, 'H': self.cursor_position, 'L': self.insert_line, #'M': self.delete_line, # TODO #'b': self.repeat_last_char, # TODO 'c': self._csi_device_status_report, # Device status report (DSR) 'g': self.__ignore, # TODO: Tab clear 'h': self._set_expanded_mode, 'l': self._reset_expanded_mode, 'f': self.cursor_position, 'd': self.cursor_position_vertical, # Vertical Line Position Absolute (VPA) #'e': self.cursor_position_vertical_relative, # VPR TODO 'J': self.clear_screen_from_cursor, 'K': self.clear_line_from_cursor, 'S': self.scroll_up, 'T': self.scroll_down, 's': self.save_cursor_position, 'u': self.restore_cursor_position, 'm': self._set_rendition, 'n': self.__ignore, # <ESC>[6n is the only one I know of (request cursor position) #'m': self.__ignore, # For testing how much CPU we save when not processing CSI 'p': self.terminal_reset, # TODO: "!p" is "Soft terminal reset". Also, "Set conformance level" (VT100, VT200, or VT300) 'r': self._set_top_bottom, # DECSTBM (used by many apps) 'q': self.set_led_state, # Seems a bit silly but you never know 'P': self.delete_characters, # DCH Deletes the specified number of chars 'X': self._erase_characters, # ECH Same as DCH but also deletes renditions 'Z': self.insert_characters, # Inserts the specified number of chars '@': self.insert_characters, # Inserts the specified number of chars #'`': self._char_position_row, # Position cursor (row only) #'t': self.window_manipulation, # TODO #'z': self.locator, # TODO: DECELR "Enable locator reporting" } self.expanded_modes = { # Expanded modes take a True/False argument for set/reset '1': self.application_mode, '2': self.__ignore, # DECANM and set VT100 mode '3': self.__ignore, # 132 Column Mode (DECCOLM) '4': self.__ignore, # Smooth (Slow) Scroll (DECSCLM) '5': self.__ignore, # Reverse video (might support in future) '6': self.__ignore, # Origin Mode (DECOM) '7': self.__ignore, # Wraparound Mode (DECAWM) '8': self.__ignore, # Auto-repeat Keys (DECARM) '9': self.__ignore, # Send Mouse X & Y on button press (maybe) '12': self.send_receive_mode, # SRM '18': self.__ignore, # Print form feed (DECPFF) '19': self.__ignore, # Set print extent to full screen (DECPEX) '25': self.show_hide_cursor, '38': self.__ignore, # Enter Tektronix Mode (DECTEK) '41': self.__ignore, # more(1) fix (whatever that is) '42': self.__ignore, # Enable Nation Replacement Character sets (DECNRCM) '44': self.__ignore, # Turn On Margin Bell '45': self.__ignore, # Reverse-wraparound Mode '46': self.__ignore, # Start Logging (Hmmm) '47': self.alternate_screen_buffer, # Use Alternate Screen Buffer '66': self.__ignore, # Application keypad (DECNKM) '67': self.__ignore, # Backarrow key sends delete (DECBKM) '1000': self.__ignore, # Send Mouse X/Y on button press and release '1001': self.__ignore, # Use Hilite Mouse Tracking '1002': self.__ignore, # Use Cell Motion Mouse Tracking '1003': self.__ignore, # Use All Motion Mouse Tracking '1010': self.__ignore, # Scroll to bottom on tty output '1011': self.__ignore, # Scroll to bottom on key press '1035': self.__ignore, # Enable special modifiers for Alt and NumLock keys '1036': self.__ignore, # Send ESC when Meta modifies a key '1037': self.__ignore, # Send DEL from the editing-keypad Delete key '1047': self.__ignore, # Use Alternate Screen Buffer '1048': self.__ignore, # Save cursor as in DECSC '1049': self.alternate_screen_buffer_cursor, # Save cursor as in DECSC and use Alternate Screen Buffer, clearing it first '1051': self.__ignore, # Set Sun function-key mode '1052': self.__ignore, # Set HP function-key mode '1060': self.__ignore, # Set legacy keyboard emulation (X11R6) '1061': self.__ignore, # Set Sun/PC keyboard emulation of VT220 keyboard } self.callbacks = { self.CALLBACK_SCROLL_UP: None, self.CALLBACK_CHANGED: None, self.CALLBACK_CURSOR_POS: None, self.CALLBACK_DSR: None, self.CALLBACK_TITLE: None, self.CALLBACK_BELL: None, self.CALLBACK_OPT: None, self.CALLBACK_MODE: None } self.leds = { 1: False, 2: False, 3: False, 4: False } # These are for saving self.screen and self.renditions so we can support # an "alternate buffer" self.alt_screen = None self.alt_renditions = None self.alt_cursorX = 0 self.alt_cursorY = 0 self.saved_cursorX = 0 self.saved_cursorY = 0 self.saved_rendition = [None] self.application_keys = False self.__linecounter = count() def init_screen(self):
[docs] """ Fills self.screen with empty lines of (unicode) spaces using self.cols and self.rows for the dimensions. NOTE: Just because each line starts out with a uniform length does not mean it will stay that way. Processing of escape sequences is handled when an output function is called. """ self.screen = [ [u' ' for a in xrange(self.cols)] for b in xrange(self.rows) ] # Tabstops tabs, remainder = divmod(self.cols, 8) # Default is every 8 chars self.tabstops = [(a*8)-1 for a in xrange(tabs)] self.tabstops[0] = 0 # Fix the first tabstop (which will be -1) # Base cursor position self.cursorX = 0 self.cursorY = 0 self.rendition_set = False def init_renditions(self):
[docs] """ Fills self.renditions with lists of None using self.cols and self.rows for the dimenions. """ self.renditions = [ [None for a in xrange(self.cols)] for b in xrange(self.rows) ] def init_scrollback(self):
[docs] """ Empties out the scrollback buffers """ self.scrollback_buf = [] self.scrollback_renditions = [] def __reset_linecounter(self):
""" Resets self.linecounter """ self.__linecounter = count() def terminal_reset(self, *args, **kwargs):
[docs] """ Resets the terminal back to an empty screen with all defaults. """ self.leds = { 1: False, 2: False, 3: False, 4: False } self.title = "Gate One" self.ignore = False self.esc_buffer = '' self.prev_esc_buffer = '' self.show_cursor = True self.rendition_set = False self.G0_charset = 'B' self.top_margin, self.bottom_margin = 0, self.rows - 1 self.alt_screen = None self.alt_renditions = None self.alt_cursorX = 0 self.alt_cursorY = 0 self.saved_cursorX = 0 self.saved_cursorY = 0 self.saved_rendition = [None] self.application_keys = False self.init_screen() self.init_renditions() self.init_scrollback() def __ignore(self, *args, **kwargs):
"""Do nothing""" pass def resize(self, rows, cols):
[docs] """ Resizes the terminal window, adding or removing rows or columns as needed. """ if rows < self.rows: # Remove rows from the top for i in xrange(self.rows - rows): self.screen.pop(0) self.renditions.pop(0) elif rows > self.rows: # Add rows at the bottom for i in xrange(rows - self.rows): line = [u' ' for a in xrange(cols)] renditions = [None for a in xrange(self.cols)] self.screen.append(line) self.renditions.append(renditions) self.rows = rows self.top_margin = 0 self.bottom_margin = self.rows - 1 # Fix the cursor location: if self.cursorY >= self.rows: self.cursorY = self.rows - 1 # TODO: Test these to make sure they're sane in all situations if cols < self.cols: # Remove cols to the right for i in xrange(self.rows): self.screen[i] = self.screen[i][:cols - self.cols] self.renditions[i] = self.renditions[i][:cols - self.cols] elif cols > self.cols: # Add cols to the right for i in xrange(self.rows): for j in xrange(cols - self.cols): self.screen[i].append(u' ') self.renditions[i].append(None) self.cols = cols # Fix the cursor location: if self.cursorX >= self.cols: self.cursorX = self.cols - 1 self.rendition_set = False def _set_top_bottom(self, settings):
""" DECSTBM - Sets self.top_margin and self.bottom_margin using the provided settings in the form of '<top_margin>;<bottom_margin>' """ # NOTE: Used by screen and vi so this needs to work and work well! if len(settings): top, bottom = settings.split(';') self.top_margin = max(0, int(top) - 1) # These are 0-based like self.cursor[XY] if bottom: self.bottom_margin = min(self.rows - 1, int(bottom) - 1) else: # Reset to defaults (full screen margins) self.top_margin, self.bottom_margin = 0, self.rows - 1 def get_cursor_position(self):
[docs] """ Returns the current cursor positition as a tuple, (row, col) """ return (self.cursorY, self.cursorX) def set_title(self, title):
[docs] """ Sets self.title to *title* and executes self.callbacks[self.CALLBACK_TITLE]() """ self.title = title try: self.callbacks[self.CALLBACK_TITLE]() except TypeError as e: print("Got TypeError on CALLBACK_TITLE...") print(repr(self.callbacks[self.CALLBACK_TITLE])) print(e) # TODO: put some logic in these save/restore functions to walk the current # rendition line to come up with a logical rendition for that exact spot. def save_cursor_position(self):
[docs] """ Saves the cursor position and current rendition settings to self.saved_cursorX, self.saved_cursorY, and self.saved_rendition """ self.saved_cursorX = self.cursorX self.saved_cursorY = self.cursorY self.saved_rendition = self.renditions[self.cursorY][self.cursorX] def restore_cursor_position(self):
[docs] """ Restores the cursor position and rendition settings from self.saved_cursorX, self.saved_cursorY, and self.saved_rendition (if they're set). """ if self.saved_cursorX and self.saved_cursorY: self.cursorX = self.saved_cursorX self.cursorY = self.saved_cursorY self.renditions[self.cursorY][self.cursorX] = self.saved_rendition def _dsr_get_cursor_position(self):
""" Returns the current cursor positition as a DSR response in the form of: '\x1b<self.cursorY>;<self.cursorX>R'. Also executes CALLBACK_DSR with the same output as the first argument. Example: self.callbacks[self.CALLBACK_DSR]('\x1b20;123R') """ esc_cursor_pos = '\x1b%s;%sR' % (self.cursorY, self.cursorX) try: self.callbacks[self.CALLBACK_DSR](esc_cursor_pos) except TypeError: pass return esc_cursor_pos def _dcs_handler(self, string=None): """ Handles Device Control String sequences. Still haven't figured out if these really need to be implemented. """ print("TODO: Handle this DCS: %s" % string) def _set_line_params(self, param): """ This function handles the control sequences that set double and single line heights and widths. NOTE: Not actually implemented yet! """ print("TODO: Handle this line height setting: %s" % param) def set_G0_charset(self, char):
[docs] """ Sets the terminal's G0 (default) charset to the type specified by *char* Here's the possibilities: 0 DEC Special Character and Line Drawing Set A United Kingdom (UK) B United States (USASCII) 4 Dutch C Finnish 5 Finnish R French Q French Canadian K German Y Italian E Norwegian/Danish 6 Norwegian/Danish Z Spanish H Swedish 7 Swedish = Swiss NOTE: Doesn't actually do anything other than set the variable. """ self.G0_charset = char def set_G1_charset(self, char):
[docs] """ Sets the terminal's G1 (alt) charset to the type specified by *char* Here's the possibilities: 0 DEC Special Character and Line Drawing Set A United Kingdom (UK) B United States (USASCII) 4 Dutch C Finnish 5 Finnish R French Q French Canadian K German Y Italian E Norwegian/Danish 6 Norwegian/Danish Z Spanish H Swedish 7 Swedish = Swiss NOTE: Doesn't actually do anything other than set the variable. """ self.G1_charset = char def write(self, chars):
[docs] """ Write *chars* to the terminal at the current cursor position advancing the cursor as it does so. If *chars* is not unicode, it will be converted to unicode before being stored in self.screen. """ # Speedups (don't want dots in loops if they can be avoided) specials = self.specials esc_handlers = self.esc_handlers csi_handlers = self.csi_handlers RE_ESC_SEQ = self.RE_ESC_SEQ RE_CSI_ESC_SEQ = self.RE_CSI_ESC_SEQ cursor_right = self.cursor_right changed = False for char in chars: charnum = ord(char) if charnum in specials: specials[charnum]() elif not self.ignore: # Now handle the regular characters and escape sequences if self.esc_buffer: # We've got an escape sequence going on... try: self.esc_buffer += char # First try to handle non-CSI ESC sequences (the basics) match_obj = RE_ESC_SEQ.match(self.esc_buffer) if match_obj: seq_type = match_obj.group(1) # '\x1bA' -> 'A' # Call the matching ESC handler if len(seq_type) == 1: # Single-character sequnces esc_handlers[seq_type]() else: # Multi-character stuff like '\x1b)B' esc_handlers[seq_type[0]](seq_type[1:]) self.prev_esc_buffer = self.esc_buffer self.esc_buffer = '' # All done with this one continue # Next try to handle CSI ESC sequences match_obj = RE_CSI_ESC_SEQ.match(self.esc_buffer) if match_obj: csi_values = match_obj.group(1) # e.g. '0;1;37' csi_type = match_obj.group(2) # e.g. 'm' if csi_type == 'm': self.rendition_set = True # Call the matching CSI handler csi_handlers[csi_type](csi_values) self.prev_esc_buffer = self.esc_buffer self.esc_buffer = '' continue except KeyError: # No handler for this, try some alternatives if self.esc_buffer.endswith('\x1b\\'): self._osc_handler() else: print( "Warning: No ESC sequence handler for %s" % `self.esc_buffer` ) self.esc_buffer = '' continue # We're done here # TODO: Figure out a way to write characters past the edge of the screen so that users can copy & paste without having newlines in the middle of everything. if self.local_echo: changed = True if self.cursorX >= self.cols: # Start a newline but NOTE: Not really the best way to # handle this because it means copying and pasting lines # will end up broken into pieces of size=self.cols self._newline() self.cursorX = 0 if not self.rendition_set: # If no rendition was just set on this position empty it self.renditions[self.cursorY][self.cursorX] = None if self.G0_charset == '0': self.screen[self.cursorY][self.cursorX] = self.charsets[ '0'][charnum] else: self.screen[self.cursorY][self.cursorX] = unicode(char) self.prev_esc_buffer = '' cursor_right() self.rendition_set = False if changed: # Execute our callbacks try: self.callbacks[self.CALLBACK_CHANGED]() except TypeError: pass try: self.callbacks[self.CALLBACK_CURSOR_POS]() except TypeError: pass def flush(self):
[docs] """ Only here to make Terminal compatible with programs that want to use file-like methods. """ pass def scroll_up(self, n=1):
[docs] """ Scrolls up the terminal screen by *n* lines (default: 1). The callbacks CALLBACK_CHANGED and CALLBACK_SCROLL_UP are called after scrolling the screen. NOTE: This will only scroll up the region within self.top_margin and self.bottom_margin (if set). """ for x in xrange(int(n)): line = self.screen.pop(self.top_margin) # Remove the top line self.scrollback_buf.append(line) # Add it to the scrollback buffer empty_line = [u' ' for a in xrange(self.cols)] # Line full of spaces # Add it to the bottom of the window: self.screen.insert(self.bottom_margin, empty_line) # Remove top line's style information style = self.renditions.pop(self.top_margin) self.scrollback_renditions.insert(self.bottom_margin, style) # Insert a new empty rendition as well: self.renditions.insert( self.bottom_margin, [None for a in xrange(self.cols)]) # Execute our callback indicating lines have been updated try: self.callbacks[self.CALLBACK_CHANGED]() except TypeError: pass # Execute our callback to scroll up the screen try: self.callbacks[self.CALLBACK_SCROLL_UP]() except TypeError: pass def scroll_down(self, n=1):
[docs] """ Scrolls down the terminal screen by *n* lines (default: 1). The callbacks CALLBACK_CHANGED and CALLBACK_SCROLL_DOWN are called after scrolling the screen. """ for x in xrange(int(n)): line = self.screen.pop(self.bottom_margin) # Remove the bottom line empty_line = [u' ' for a in xrange(self.cols)] # Line full of spaces self.screen.insert(self.top_margin, empty_line) # Add it to the top # Remove bottom line's style information: style = self.renditions.pop(self.bottom_margin) # Insert a new empty one: self.renditions.insert( self.top_margin, [None for a in xrange(self.cols)]) # Execute our callback indicating lines have been updated try: self.callbacks[self.CALLBACK_CHANGED]() except TypeError: pass # Execute our callback to scroll up the screen try: self.callbacks[self.CALLBACK_SCROLL_UP]() except TypeError: pass def insert_line(self, n):
[docs] """ Inserts a line at the current cursor position. """ line = self.screen.pop(self.bottom_margin) # Remove the bottom line # Remove bottom line's style information as well: style = self.renditions.pop(self.bottom_margin) empty_line = [u' ' for a in xrange(self.cols)] # Line full of spaces self.screen.insert(self.cursorY, empty_line) # Insert at cursor # Insert a new empty rendition as well: self.renditions.insert(self.cursorY, [None for a in xrange(self.cols)]) def _backspace(self):
"""Execute a backspace (\x08)""" self.cursor_left(1) def _horizontal_tab(self): """Execute horizontal tab (\x09)""" next_tabstop = self.cols -1 for tabstop in self.tabstops: if tabstop > self.cursorX: next_tabstop = tabstop break self.cursorX = next_tabstop self.rendition_set = False def _set_tabstop(self): """Sets a tabstop at the current position of self.cursorX.""" if self.cursorX not in self.tabstops: for tabstop in self.tabstops: if self.cursorX > tabstop: self.tabstops.append(self.cursorX) self.tabstops.sort() # Put them in order :) break def _linefeed(self): """Execute line feed""" self._newline() def _next_line(self): """Moves cursor down one line""" if self.cursorY < self.rows -1: self.cursorY += 1 def _reverse_linefeed(self): self.cursorX = 0 self.cursorY -= 1 if self.cursorY < self.top_margin: self.scroll_down() self.cursorY = self.top_margin def _newline(self): """ Adds a new line to self.screen and sets self.cursorX to 0. """ self.cursorY += 1 if self.cursorY > self.bottom_margin: self.scroll_up() self.cursorY = self.bottom_margin self.clear_line() self.rendition_set = False def _carriage_return(self): """ Execute carriage return (set self.cursorX to 0) """ self.cursorX = 0 self.rendition_set = False def _xon(self): """ Handle XON character (stop ignoring) """ self.ignore = False def _xoff(self): """ Handle XOFF character (start ignoring) """ self.ignore = True def _cancel_esc_sequence(self): """Cancels any escape sequence currently in progress.""" self.esc_buffer = '' def _sub_esc_sequence(self): """ Cancels any escape sequence currently in progress and substitutes it with single question mark (?). """ self.esc_buffer = '' self.write('?') def _escape(self): """ Handle escape character as well as escape sequences. """ buf = self.esc_buffer if buf.startswith('\x1bP') or buf.startswith('\x1b]'): # CSRs and OSCs are special self.esc_buffer += '\x1b' else: # Get rid of whatever's there since we obviously didn't know what to # do with it self.esc_buffer = '\x1b' def _string_terminator(self): """ Handle the string terminator. """ # TODO: This. # NOTE: Might this just call _cancel_esc_sequence? I need to double-check. pass def _osc_handler(self): """ Handles Operating System Command (OSC) escape sequences which need special care since they are of indeterminiate length and end with either a bell (\x07) or a sequence terminator (\x9c aka ST). This will usually called from self._bell() to set the title of the terminal (just like an xterm) but it is also possible to be called directly whenever an ST is encountered. """ # Try the title sequence first match_obj = self.RE_TITLE_SEQ.match(self.esc_buffer) if match_obj: title = match_obj.group(1) self.set_title(title) # Sets self.title self.esc_buffer = '' return # Next try our special optional handler sequence match_obj = self.RE_OPT_SEQ.match(self.esc_buffer) if match_obj: text = match_obj.group(1) self.__opt_handler(text) self.esc_buffer = '' return def _bell(self): """ Handle bell character and execute self.CALLBACKS[CALLBACK_BELL]() if we are not in the middle of an escape sequence. If we *are* in the middle of an escape sequence, call self._osc_handler() since we can be nearly certain that we're simply terminating an OSC sequence. """ # NOTE: A little explanation is in order: The bell character (\x07) by # itself should play a bell (pretty straighforward). However, if # the bell character is at the tail end of a particular escape # sequence (string starting with \x1b]0;) this indicates an xterm # title (everything between \x1b]0;...\x07). if not self.esc_buffer: # We're not in the middle of an esc sequence try: self.callbacks[self.CALLBACK_BELL]() except TypeError: pass else: # We're (likely) setting a title self.esc_buffer += '\x07' # Add the bell char so we don't lose it self._osc_handler() def _device_status_report(self): """ Returns '\x1b[0n' (terminal OK) and executes self.callbacks[self.CALLBACK_DSR]("\x1b[0n"). """ response = "\x1b[0n" try: self.callbacks[self.CALLBACK_DSR](response) except TypeError: pass return response def _csi_device_status_report(self, request): """ Returns '\x1b[1;2c' (Meaning: I'm a vt220 terminal, version 1.0) and executes self.callbacks[self.CALLBACK_DSR]("\x1b[1;2c"). """ response = "\x1b[1;2c" try: self.callbacks[self.CALLBACK_DSR](response) except TypeError: pass return response def _set_expanded_mode(self, setting): """ Accepts "standard mode" settings. Typically '\x1b[?25h' to hide cursor. Notes on modes:: '?1h' - Application Cursor Keys '?12h' - Local echo (SRM or Send Receive Mode) '?25h' - Hide cursor '?1049h' - Save cursor and screen """ # TODO: Add support for the following: # * 3: 132 column mode (might be "or greater") # * 4: Smooth scroll (for animations and also makes things less choppy) # * 5: Reverse video (should be easy: just need some extra CSS) # * 6: Origin mode # * 7: Wraparound mode setting = setting[1:] # Don't need the ? settings = setting.split(';') for setting in settings: try: self.expanded_modes[setting](True) except (KeyError, TypeError): pass # Unsupported expanded mode try: self.callbacks[self.CALLBACK_MODE](setting, True) except TypeError: pass def _reset_expanded_mode(self, setting): """ Accepts "standard mode" settings. Typically '\x1b[?25l' to show cursor. """ setting = setting[1:] # Don't need the ? settings = setting.split(';') for setting in settings: try: self.expanded_modes[setting](False) except (KeyError, TypeError): pass # Unsupported expanded mode try: self.callbacks[self.CALLBACK_MODE](setting, False) except TypeError: pass def application_mode(self, boolean):
[docs] """self.application_keys = *boolean*""" self.application_keys = boolean def alternate_screen_buffer(self, alt):
[docs] """ If *alt* is True, copy the current screen and renditions to self.alt_screen and self.alt_renditions then re-init self.screen and self.renditions. If *alt* is False, restore the saved screen buffer and renditions then nullify self.alt_screen and self.alt_renditions. """ if alt: # Save the existing screen and renditions self.alt_screen = copy.copy(self.screen) self.alt_renditions = copy.copy(self.renditions) # Make a fresh one self.clear_screen() else: # Restore the screen if self.alt_screen and self.alt_renditions: self.screen = self.alt_screen self.renditions = self.alt_renditions # Empty out the alternate buffer (to save memory) self.alt_screen = None self.alt_renditions = None def alternate_screen_buffer_cursor(self, alt):
[docs] """ Same as self.alternate_screen_buffer but saves/restores the cursor location. """ if alt: self.alt_cursorX = self.cursorX self.alt_cursorY = self.cursorY else: self.cursorX = self.alt_cursorX self.cursorY = self.alt_cursorY self.alternate_screen_buffer(alt) self.rendition_set = False def show_hide_cursor(self, boolean):
[docs] """self.show_cursor = boolean""" self.show_cursor = boolean def send_receive_mode(self, onoff):
[docs] """ Turns on or off local echo dependong on the value of *onoff* self.local_echo = *onoff* """ if onoff: self.local_echo = False else: self.local_echo = True def insert_characters(self, n=1):
[docs] """Inserts the specified number of characters at the cursor position""" n = int(n) for i in xrange(n): self.screen[self.cursorY].pop() # Take one down, pass it around self.screen[self.cursorY].insert(self.cursorX, u' ') def delete_characters(self, n=1):
[docs] """ DCH - Deletes (to the left) the specified number of characters at the cursor position. As characters are deleted, the remaining characters between the cursor and right margin move to the left. Character attributes (renditions) move with the characters. The terminal adds blank spaces with no visual character attributes at the right margin. DCH has no effect outside the scrolling margins. NOTE: Deletes renditions too. """ if not n: # e.g. n == '' n = 1 else: n = int(n) for i in xrange(n): try: self.screen[self.cursorY].pop(self.cursorX) self.screen[self.cursorY].append(u' ') self.renditions[self.cursorY].pop(self.cursorX) self.renditions[self.cursorY].append(None) except IndexError: # At edge of screen, ignore pass def _erase_characters(self, n=1):
""" Erases (to the right) the specified number of characters at the cursor position. NOTE: Deletes renditions too. """ if not n: # e.g. n == '' n = 1 else: n = int(n) distance = self.cols - self.cursorX n = min(n, distance) for i in xrange(n): self.screen[self.cursorY][self.cursorX+i] = u' ' self.renditions[self.cursorY][self.cursorX+i] = None def cursor_left(self, n=1):
[docs] """ESCnD CUB (Cursor Back)""" n = int(n) self.cursorX = max(0, self.cursorX - n) try: self.callbacks[self.CALLBACK_CURSOR_POS]() except TypeError: pass self.rendition_set = False def cursor_right(self, n=1):
[docs] """ESCnC CUF (Cursor Forward)""" if not n: n = 1 n = int(n) self.cursorX += 1 try: self.callbacks[self.CALLBACK_CURSOR_POS]() except TypeError: pass self.rendition_set = False def cursor_up(self, n=1):
[docs] """ESCnA CUU (Cursor Up)""" if not n: n = 1 n = int(n) self.cursorY = max(0, self.cursorY - n) self.rendition_set = False try: self.callbacks[self.CALLBACK_CURSOR_POS]() except TypeError: pass def cursor_down(self, n=1):
[docs] """ESCnB CUD (Cursor Down)""" if not n: n = 1 n = int(n) self.cursorY = min(self.rows, self.cursorY + n) self.rendition_set = False try: self.callbacks[self.CALLBACK_CURSOR_POS]() except TypeError: pass def cursor_next_line(self, n):
[docs] """ESCnE CNL (Cursor Next Line)""" if not n: n = 1 n = int(n) self.cursorY = min(self.rows, self.cursorY + n) self.cursorX = 0 self.rendition_set = False try: self.callbacks[self.CALLBACK_CURSOR_POS]() except TypeError: pass def cursor_previous_line(self, n):
[docs] """ESCnF CPL (Cursor Previous Line)""" if not n: n = 1 n = int(n) self.cursorY = max(0, self.cursorY - n) self.cursorX = 0 self.rendition_set = False try: self.callbacks[self.CALLBACK_CURSOR_POS]() except TypeError: pass def cursor_horizontal_absolute(self, n):
[docs] """ESCnG CHA (Cursor Horizontal Absolute)""" if not n: n = 1 n = int(n) self.cursorX = n - 1 # -1 because cols is 0-based self.rendition_set = False try: self.callbacks[self.CALLBACK_CURSOR_POS]() except TypeError: pass def cursor_position(self, coordinates):
[docs] """ ESCnH CUP (Cursor Position). Move the cursor to the given coordinates. *coordinates*: Should be something like, 'row;col' (1-based) but, 'row', 'row;', and ';col' are also valid (assumes 1 on missing value). If coordinates is '', the cursor will be moved to the top left (1;1). """ # NOTE: Since this is 1-based we have to subtract 1 from everything to # match how we store these values internally. if not coordinates: row, col = 0, 0 elif ';' in coordinates: row, col = coordinates.split(';') else: row = coordinates col = 0 try: row = int(row) except ValueError: row = 0 try: col = int(col) except ValueError: col = 0 # These ensure a positive integer while reducing row and col by 1: row = max(0, row - 1) col = max(0, col - 1) self.cursorY = row self.cursorX = col self.rendition_set = False try: self.callbacks[self.CALLBACK_CURSOR_POS]() except TypeError: pass def cursor_position_vertical(self, n):
[docs] """ Vertical Line Position Absolute (VPA) - Moves the cursor to given line. """ n = int(n) self.cursorY = n - 1 self.rendition_set = False def clear_screen(self):
[docs] """ Clears the screen. Also used to emulate a terminal reset. """ self.init_screen() self.init_renditions() self.cursorX = 0 self.cursorY = 0 self.rendition_set = False def clear_screen_from_cursor_down(self):
[docs] """ Clears the screen from the cursor down (Esc[J or Esc[0J). """ self.screen[self.cursorY:] = [ [u' ' for a in xrange(self.cols)] for a in self.screen[self.cursorY:] ] self.renditions[self.cursorY:] = [ [None for a in xrange(self.cols)] for a in self.screen[self.cursorY:] ] self.cursorX = 0 self.rendition_set = False def clear_screen_from_cursor_up(self):
[docs] """ Clears the screen from the cursor up (Esc[1J). """ self.screen[:self.cursorY+1] = [ [u' ' for a in xrange(self.cols)] for a in self.screen[:self.cursorY] ] self.renditions[:self.cursorY+1] = [ [None for a in xrange(self.cols)] for a in self.screen[:self.cursorY] ] self.cursorX = 0 self.cursorY = 0 self.rendition_set = False def clear_screen_from_cursor(self, n):
[docs] """ CSI*n*J ED (Erase Data). This escape sequence uses the following rules:: Esc[J Clear screen from cursor down ED0 Esc[0J Clear screen from cursor down ED0 Esc[1J Clear screen from cursor up ED1 Esc[2J Clear entire screen ED2 """ try: n = int(n) except ValueError: # Esc[J n = 0 clear_types = { 0: self.clear_screen_from_cursor_down, 1: self.clear_screen_from_cursor_up, 2: self.clear_screen } try: clear_types[n]() except KeyError: print("Error: Unsupported number for escape sequence J") # Execute our callbacks try: self.callbacks[self.CALLBACK_CHANGED]() except TypeError: pass try: self.callbacks[self.CALLBACK_CURSOR_POS]() except TypeError: pass def clear_line_from_cursor_right(self):
[docs] """ Clears the screen from the cursor right (Esc[K or Esc[0K). """ self.screen[self.cursorY][self.cursorX:] = [ u' ' for a in self.screen[self.cursorY][self.cursorX:]] # NOTE: We have to check if a rendition was just set for this cursor # position since \x1b[K is only supposed to clear renditions that # were set prior to the cursor being placed at its current # position (which is odd--and I can't find any documentation that # says that's how it is supposed to work but it seems to be the # case in real-world testing). if self.prev_esc_buffer.endswith('m'): # Was a rendition, preserve it self.renditions[self.cursorY][self.cursorX+1:] = [ None for a in self.screen[self.cursorY][self.cursorX:]] else: # Reset the cursor position's rendition to the end of the line self.renditions[self.cursorY][self.cursorX:] = [ None for a in self.screen[self.cursorY][self.cursorX:]] def clear_line_from_cursor_left(self):
[docs] """ Clears the screen from the cursor left (Esc[1K). """ saved = self.screen[self.cursorY][self.cursorX:] saved_renditions = self.renditions[self.cursorY][self.cursorX:] self.screen[self.cursorY] = [ u' ' for a in self.screen[self.cursorY][:self.cursorX] ] + saved self.renditions[self.cursorY] = [ None for a in self.screen[self.cursorY][:self.cursorX] ] + saved_renditions def clear_line(self):
[docs] """ Clears the entire line (Esc[2K). """ self.screen[self.cursorY] = [u' ' for a in xrange(self.cols)] self.renditions[self.cursorY] = [None for a in xrange(self.cols)] self.cursorX = 0 self.rendition_set = False def clear_line_from_cursor(self, n):
[docs] """ CSI*n*K EL (Erase in Line). This escape sequence uses the following rules:: Esc[K Clear screen from cursor right EL0 Esc[0K Clear screen from cursor right EL0 Esc[1K Clear screen from cursor left EL1 Esc[2K Clear entire line ED2 """ try: n = int(n) except ValueError: # Esc[J n = 0 clear_types = { 0: self.clear_line_from_cursor_right, 1: self.clear_line_from_cursor_left, 2: self.clear_line } try: clear_types[n]() except KeyError: print("Error: Unsupported number for CSI escape sequence K") # Execute our callbacks try: self.callbacks[self.CALLBACK_CHANGED]() except TypeError: pass try: self.callbacks[self.CALLBACK_CURSOR_POS]() except TypeError: pass def set_led_state(self, n):
[docs] """ Sets the values the dict, self.leds depending on *n* using the following rules: Esc[0q Turn off all four leds DECLL0 Esc[1q Turn on LED #1 DECLL1 Esc[2q Turn on LED #2 DECLL2 Esc[3q Turn on LED #3 DECLL3 Esc[4q Turn on LED #4 DECLL4 """ states = n.split(';') for state in states: state = int(state) if state == 0: self.leds[1] = False self.leds[2] = False self.leds[3] = False self.leds[4] = False else: self.leds[state] = True def __reduce_renditions(self, renditions):
""" Takes a list, *renditions*, and reduces it to its logical equivalent (as far as renditions go). Example: [0, 32, 0, 34, 0, 32] Would become: [0, 32] Other Examples: [0, 1, 36, 36] -> [0, 1, 36] [0, 30, 42, 30, 42] -> [0, 30, 42] [36, 32, 44, 42] -> [32, 42] """ out_renditions = [] foreground = None background = None for i, rend in enumerate(renditions): if rend < 29: if rend not in out_renditions: out_renditions.append(rend) elif rend > 29 and rend < 40: foreground = rend elif rend > 39 and rend < 50: background = rend else: out_renditions.append(rend) if foreground: out_renditions.append(foreground) if background: out_renditions.append(background) return out_renditions def _set_rendition(self, n): """ Sets self.renditions[self.cursorY][self.cursorX] equal to n.split(';'). *n* is expected to be a string of ECMA-48 rendition numbers separated by semicolons. Example: '0;1;31' ...will result in: [0, 1, 31] Note that the numbers were converted to integers and the order was preserved. """ # TODO: Make this whole thing faster (or prove it isn't possible). cursorY = self.cursorY cursorX = self.cursorX if cursorX >= self.cols: # We're at the end of the row return #cursorY += 1 # Set the rendition for the next line #cursorX = 0 if cursorY >= self.rows: return # Don't bother setting renditions past the bottom if not n: # or \x1b[m (reset) self.renditions[cursorY][cursorX] = [0] return # No need for further processing; save some CPU # Convert the string (e.g. '0;1;32') to a list (e.g. [0,1,32] new_renditions = [int(a) for a in n.split(';') if a != ''] if self.renditions[cursorY][cursorX] == new_renditions: return # Nothing left to do if self.renditions[cursorY][cursorX]: # Existing rendition for this spot... Tack it on the end self.renditions[cursorY][cursorX] += new_renditions # Remove duplicates and unnecessary renditions self.renditions[cursorY][cursorX] = self.__reduce_renditions( self.renditions[cursorY][cursorX]) else: self.renditions[cursorY][cursorX] = self.__reduce_renditions(new_renditions) def __opt_handler(self, chars): """ Optional special escape sequence handler for sequences matching RE_OPT_SEQ. If self.CALLBACK_OPT is defined it will be called like so: self.CALLBACKS[self.CALLBACK_OPT](chars) Applications can use this escape sequence to define whatever special handlers they like. It works like this: If an escape sequence is encountered matching RE_OPT_SEQ this method will be called with the inbetween *chars* (e.g. \x1b]_;<chars>\x07) as the argument. Applications can then do what they wish with *chars*. NOTE: I added this functionality so that plugin authors would have a mechanism to communicate with terminal applications. See the SSH plugin for an example of how this can be done (there's channels of communication amongst ssh_connect.py, ssh.js, and ssh.py). """ try: self.callbacks[self.CALLBACK_OPT](chars) except TypeError as e: # High likelyhood that nothing is defined. No biggie. pass def __spanify_line(self, lines, renditions): """ Iterates over *line* and *renditions*, applying HTML markup (spans) where appropriate and returns a single line as the result. It also marks the cursor position via a <span> tag at the appropriate location. """ linecount = self.__linecounter.next() outline = "" charcount = 0 rendition_classes = RENDITION_CLASSES cursorX = self.cursorX cursorY = self.cursorY classcount = 0 spancount = 0 current_classes = [] foregrounds = ('f0','f1','f2','f3','f4','f5','f6','f7') backgrounds = ('b0','b1','b2','b3','b4','b5','b6','b7') for char, rendition in izip(lines, renditions): if char in "<>": # Have to convert lt/gt to HTML entities char = char.replace('<', '&lt;') char = char.replace('>', '&gt;') if rendition != None: classes = imap(rendition_classes.get, rendition) same_as_before = True for _class in classes: if _class not in current_classes: # Something changed... Start a new span same_as_before = False if spancount: outline += "</span>" spancount -= 1 if 'reset' in _class: if _class == 'reset': current_classes = [] else: reset_class = _class.split('reset')[0] if reset_class == 'foreground': # Remove any foreground classes [current_classes.pop(i) for i, a in enumerate(current_classes) if a in foregrounds ] elif reset_class == 'background': [current_classes.pop(i) for i, a in enumerate(current_classes) if a in backgrounds ] else: try: current_classes.remove(reset_class) except ValueError: # Trying to reset something that was # never set. Ignore pass else: if _class in foregrounds: [current_classes.pop(i) for i, a in enumerate(current_classes) if a in foregrounds ] elif _class in backgrounds: [current_classes.pop(i) for i, a in enumerate(current_classes) if a in backgrounds ] current_classes.append(_class) if current_classes and not same_as_before: outline += '<span class="%s">' % " ".join(current_classes) spancount += 1 if linecount == cursorY and charcount == cursorX: # Cursor position if self.show_cursor: outline += '<span class="cursor">%s</span>' % char else: outline += char # Use the simpler self.__spanify_line_no_cursor as a speedup: self.__temp = self.__spanify_line self.__spanify_line = self.__spanify_line_no_cursor else: outline += char charcount += 1 for whatever in xrange(spancount): outline += "</span>" return outline def __spanify_line_no_cursor(self, lines, renditions): """ Iterates over *lines* and *renditions*, applying HTML markup (spans) where appropriate and returns a single line as the result. """ outline = "" classcount = 0 charcount = 0 rendition_classes = RENDITION_CLASSES spancount = 0 current_classes = [] foregrounds = ('f0','f1','f2','f3','f4','f5','f6','f7') backgrounds = ('b0','b1','b2','b3','b4','b5','b6','b7') for char, rendition in izip(lines, renditions): if char in "<>": # Have to escape lt/gt char = char.replace('<', '&lt;') char = char.replace('>', '&gt;') if rendition != None: classes = imap(rendition_classes.get, rendition) for _class in classes: if _class not in current_classes: # Something changed... Start a new span if spancount: outline += "</span>" spancount -= 1 if 'reset' in _class: if _class == 'reset': current_classes = [] else: reset_class = _class.split('reset')[0] if reset_class == 'foreground': # Remove any foreground classes [current_classes.pop(i) for i, a in enumerate(current_classes) if a in foregrounds ] elif reset_class == 'background': [current_classes.pop(i) for i, a in enumerate(current_classes) if a in backgrounds ] else: try: current_classes.remove(reset_class) except ValueError: # Trying to reset something that was # never set. Ignore pass else: if _class in foregrounds: [current_classes.pop(i) for i, a in enumerate(current_classes) if a in foregrounds ] elif _class in foregrounds: [current_classes.pop(i) for i, a in enumerate(current_classes) if a in foregrounds ] current_classes.append(_class) if current_classes: outline += '<span class="%s">' % " ".join(current_classes) spancount += 1 outline += char charcount += 1 for whatever in xrange(spancount): outline += "</span>" return outline def dump_html(self):
[docs] """ Dumps the terminal screen as a list of HTML-formatted lines. Note: This places <span class="cursor">(current character)</span> around the cursor location. """ results = map(self.__spanify_line, self.screen, self.renditions) self.__reset_linecounter() # Reset self.__spanify_line back to default: try: self.__spanify_line = self.__temp del self.__temp except AttributeError: pass # No cursor yet scrollback = [] if self.scrollback_buf: # Process the scrollback buffer too scrollback = map( self.__spanify_line_no_cursor, # Slightly faster self.scrollback_buf, self.scrollback_renditions ) # Empty the scrollback buffer: self.init_scrollback() self.__reset_linecounter() return (scrollback, results) def dump_plain(self):
[docs] """ Dumps the screen and the scrollback buffer as-is then empties the scrollback buffer. """ screen = self.screen scrollback = self.scrollback_buf # Empty the scrollback buffer: self.init_scrollback() return (scrollback, screen) def dump_components(self):
[docs] """ Dumps the screen and renditions as-is, the scrollback buffer as HTML, and the current cursor coordinates. Also, empties the scrollback buffer NOTE: Was used in some performance-related experiments but might be useful for other patterns in the future so I've left it here. """ screen = [a.tounicode() for a in self.screen] scrollback = [] if self.scrollback_buf: # Process the scrollback buffer into HTML scrollback = map( self.__spanify_line_no_cursor, # Slightly faster (no cursor logic) self.scrollback_buf, self.scrollback_renditions ) # Empty the scrollback buffer: self.init_scrollback() return (scrollback, screen, self.renditions, self.cursorY, self.cursorX) def dump(self):
[docs] """ Returns self.screen as a list of strings with no formatting. No scrollback buffer. No renditions. NOTE: Does not empty the scrollback buffer. Primarily used to get a quick glance of what is being displayed (when debugging). """ out = [] for line in self.screen: out.append("".join(line)) return out