godot-xterm/addons/godot_xterm/terminal.gd
Leroy Hopson 9ed6750b83
Fix unicode errors
Changes `write()` method of native pipe and terminal to accept a
PoolByteArray rather than String. This means that `get_string_from_utf8()`
is no longer called on data coming from PTY and being sent to Terminal.

The terminal state machine already has a UTF8 parser which maintains
its state across calls to `write()`. This means that we can write half
the bytes of a single unicode character in one call and the remaining half
in the next call and the state machine will parse it correctly.

On the other hand, the `get_string_from_utf8()` method of Godot's
PoolByteArray requires that the array contains completely valid UTF8,
otherwise we get errors such as "Unicode error: invalid skip".

The data coming from PTY can be arbitrarily split in the middle of a
unicode character meaning that we will sometimes get errors when calling
`get_string_from_utf8()` on it. This is more likely to occur when there
is a large amount of output (i.e. it's more likely to be split). In other
cases, the data might intentionally contain invalid unicode such as when
printing binary files or random data (e.g. `cat /bin/sh`, `cat /dev/random`).

We avoid these errors by passing the PoolByteArray data directly to the terminal
state machine.

In addition to fixing unicode errors, this commit:
- Prevents repeated calls to pipes `_read_cb()` method that would block Godot
  and result in a crash with the message "ERROR: All memory pool allocations
  are in use" that resulted from writing data to an ever-increasing number of
  PoolByteArrays before any of them could be freed. This could be triggered by
  running the `cat /dev/urandom` command after making the change to `write()`
  mentioned above.
- Prevents memory leaks by freeing libuv buffers after they have been copied
  to PoolByteArrays.

Fixes #55.
2022-08-15 17:09:29 +12:00

300 lines
8 KiB
GDScript

# Copyright (c) 2021, Leroy Hopson (MIT License).
#
# This file contains snippets of code derived from Godot's TextEdit node.
# These snippets are copyright of their authors and released under the MIT license:
# - Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur (MIT License).
# - Copyright (c) 2014-2021 Godot Engine contributors (MIT License).
tool
extends Control
signal data_sent(data)
signal key_pressed(data, event)
signal size_changed(new_size)
signal bell
enum UpdateMode {
DISABLED,
AUTO,
ALL,
ALL_NEXT_FRAME,
}
enum SelectionMode {
NONE,
POINTER,
}
export(UpdateMode) var update_mode = UpdateMode.AUTO setget set_update_mode
var cols = 2
var rows = 2
# If true, text in the terminal will be copied to the clipboard when selected.
export(bool) var copy_on_selection
# Bell
# If muted, the "bell" signal will not be emitted when the bell "\u0007" character
# is written to the terminal.
export var bell_muted := false
# Amount of time in seconds that must pass before emitting a new "bell" signal.
# This can be useful in cases where the bell character is being written too
# frequently such as `while true; do echo -e "\a"; done`.
export var bell_cooldown: float = 0.1
export var blink_on_time: float = 0.6
export var blink_off_time: float = 0.3
var _default_theme: Theme = preload("./themes/default.tres")
var _viewport: Viewport = preload("./nodes/terminal/viewport.tscn").instance()
var _native_terminal: Control = _viewport.get_node("Terminal")
var _screen := TextureRect.new()
var _bell_timer := Timer.new()
var _selecting := false
var _selecting_mode: int = SelectionMode.NONE
var _selection_timer := Timer.new()
var _dirty := false
var buffer := StreamPeerBuffer.new()
var times = 0
var _buffer := []
func set_update_mode(value):
update_mode = value
_native_terminal.update_mode = value
func get_rows() -> int:
return 0
func get_cols() -> int:
return 0
func write(data) -> void:
assert(
data is PoolByteArray or data is String,
"Invalid type for argument 'data'. Should be of type PoolByteArray or String."
)
# Will be cleared when _flush() is called after VisualServer emits the "frame_pre_draw" signal.
_buffer.push_back(data)
# Ensure redraw is requested if terminal is visible.
if visible:
update()
func _flush():
for data in _buffer:
_native_terminal.write(data if data is PoolByteArray else data.to_utf8())
_native_terminal.update()
_buffer.clear()
func clear() -> void:
var initial_size = _native_terminal.rect_size
_native_terminal.rect_size.y = _native_terminal.cell_size.y
_native_terminal.clear_sb()
_native_terminal.rect_size = initial_size
func copy_selection() -> String:
return _native_terminal.copy_selection()
func copy_all() -> String:
return _native_terminal.copy_all()
func _ready():
_update_theme()
_native_terminal.update_mode = update_mode
_native_terminal.connect("data_sent", self, "_on_data_sent")
_native_terminal.connect("key_pressed", self, "_on_key_pressed")
_native_terminal.connect("size_changed", self, "_on_size_changed")
_viewport.size = rect_size
_viewport.render_target_update_mode = Viewport.UPDATE_ALWAYS
_screen.set_anchors_preset(PRESET_WIDE)
_screen.texture = _viewport.get_texture()
_native_terminal.connect("bell", self, "_on_bell")
_bell_timer.one_shot = true
add_child(_bell_timer)
_selection_timer.wait_time = 0.05
_selection_timer.connect("timeout", self, "_on_selection_held")
add_child(_viewport)
add_child(_screen)
add_child(_selection_timer)
_refresh()
# Ensure the terminal state machine's framebuffer is up to date before
# we make all the draw_* calls caused by writing. We need to use signals
# here rather than yield otherwise we will sometimes get a "Resumed
# function after yield but class instance is gone" error.
VisualServer.connect("frame_pre_draw", self, "_flush")
func _update_theme():
# Themes are not propagated through the Viewport, so in order for theme
# inheritance to work we can pass through the theme variables manually.
for color in _default_theme.get_color_list("Terminal"):
var c: Color
if has_color(color, "Terminal"):
c = get_color(color, "Terminal")
else:
c = _default_theme.get_color(color, "Terminal")
_native_terminal.add_color_override(color, c)
for font in _default_theme.get_font_list("Terminal"):
var f: Font
if has_font(font, "Terminal"):
f = get_font(font, "Terminal")
elif has_font("Regular", "Terminal"):
f = get_font("Regular", "Terminal")
else:
if _default_theme.has_font(font, "Terminal"):
f = _default_theme.get_font(font, "Terminal")
else:
f = _default_theme.get_font(font, "Regular")
_native_terminal.add_font_override(font, f)
_native_terminal._update_theme()
_native_terminal._update_size()
func _refresh():
_screen.update()
if update_mode == UpdateMode.AUTO:
_native_terminal.update_mode = UpdateMode.ALL_NEXT_FRAME
func _gui_input(event):
_native_terminal._gui_input(event)
if event is InputEventKey and event.pressed:
# Return to bottom of scrollback buffer if we scrolled up. Ignore modifier
# keys pressed in isolation or if Ctrl+Shift modifier keys are pressed.
if (
not event.scancode in [KEY_ALT, KEY_SHIFT, KEY_CONTROL, KEY_META, KEY_MASK_CMD]
and not (event.control and event.shift)
):
_native_terminal.sb_reset()
# Prevent focus changing to other inputs when pressing Tab or Arrow keys.
if event.scancode in [KEY_LEFT, KEY_UP, KEY_RIGHT, KEY_DOWN, KEY_TAB]:
accept_event()
_handle_mouse_wheel(event)
_handle_selection(event)
func _handle_mouse_wheel(event: InputEventMouseButton):
if not event or not event.is_pressed():
return
if event.button_index == BUTTON_WHEEL_UP:
if event.alt:
# Scroll 5 times as fast as normal (like TextEdit).
_native_terminal.sb_up(15 * event.factor)
else:
# Scroll 3 lines.
_native_terminal.sb_up(3 * event.factor)
if event.button_index == BUTTON_WHEEL_DOWN:
if event.alt:
# Scroll 5 times as fast as normal (like TextEdit).
_native_terminal.sb_down(15 * event.factor)
else:
# Scroll 3 lines.
_native_terminal.sb_down(3 * event.factor)
func _handle_selection(event: InputEventMouse):
if event is InputEventMouseButton:
if not event or not event.is_pressed() or not event.button_index == BUTTON_LEFT:
return
if _selecting:
_selecting = false
_selecting_mode = SelectionMode.NONE
_native_terminal.reset_selection()
# Single-click select pointer.
_selecting = false
_selecting_mode = SelectionMode.POINTER
elif event is InputEventMouseMotion:
if (
event.button_mask & BUTTON_MASK_LEFT
and _selecting_mode != SelectionMode.NONE
and not _selecting
):
_selecting = true
_native_terminal.start_selection(_mouse_to_cell(event.position))
_selection_timer.start()
func _on_selection_held() -> void:
if not Input.is_mouse_button_pressed(BUTTON_LEFT) or _selecting_mode == SelectionMode.NONE:
if copy_on_selection:
var selection = _native_terminal.copy_selection()
OS.set_clipboard(selection)
_selection_timer.stop()
return
var position: Vector2 = _mouse_to_cell(get_local_mouse_position())
_native_terminal.select_to_pointer(position)
_selection_timer.start()
func _notification(what: int) -> void:
match what:
NOTIFICATION_RESIZED:
_viewport.size = rect_size
_refresh()
NOTIFICATION_THEME_CHANGED:
_update_theme()
_refresh()
func _on_data_sent(data: PoolByteArray):
emit_signal("data_sent", data)
func _on_key_pressed(data: PoolByteArray, event: InputEventKey):
emit_signal("key_pressed", data.get_string_from_utf8(), event)
func _on_size_changed(new_size: Vector2):
cols = new_size.x
rows = new_size.y
emit_signal("size_changed", new_size)
func _on_bell():
if not bell_muted and (bell_cooldown == 0 or _bell_timer.time_left == 0):
emit_signal("bell")
if bell_cooldown > 0:
_bell_timer.start(bell_cooldown)
func _mouse_to_cell(pos: Vector2) -> Vector2:
return Vector2(pos / _native_terminal.cell_size)
func _set_size_warning(value):
if value:
push_warning(
"Terminal cols and rows are read only and determined by the font and rect sizes."
)