Framework for remote control

__main__.py

@@ -15,21 +15,35 @@ def list_fonts(args):
     main(args)
 
 
+def remote_control(args):
+    from kitty.remote_control import main
+    main(args)
+
+
+def namespaced(args):
+    func = namespaced_entry_points[args[0]]
+    func(args[1:])
+
+
+entry_points = {
+    'icat': icat,
+    'list-fonts': list_fonts,
+    '+icat': icat,
+    '+list-fonts': list_fonts,
+    '@': remote_control,
+    '+': namespaced,
+}
+namespaced_entry_points = {k: v for k, v in entry_points.items() if k[0] not in '+@'}
+
+
 def main():
     first_arg = '' if len(sys.argv) < 2 else sys.argv[1]
-    if first_arg in ('icat', '+icat'):
-        icat(sys.argv[1:])
-    elif first_arg in ('list-fonts', '+list-fonts'):
-        list_fonts(sys.argv[1:])
-    elif first_arg == '+' and len(sys.argv) > 2:
-        q = sys.argv[2]
-        if q == 'icat':
-            icat(sys.argv[2:])
-        elif q == 'list-fonts':
-            list_fonts(sys.argv[2:])
-    else:
+    func = entry_points.get(first_arg)
+    if func is None:
         from kitty.main import main
         main()
+    else:
+        func(sys.argv[1:])
 
 
 if __name__ == '__main__':

kitty/boss.py

@@ -125,6 +125,16 @@ class Boss:
             else:
                 safe_print('Unknown message received from peer, ignoring')
 
+    def handle_remote_cmd(self, cmd, window=None):
+        response = None
+        if self.opts.allow_remote_control:
+            pass
+        else:
+            response = {'ok': False, 'err': 'NOT_ALLOWED'}
+        if response is not None:
+            if window is not None:
+                window.send_cmd_response(response)
+
     def on_child_death(self, window_id):
         window = self.window_id_map.pop(window_id, None)
         if window is None:

kitty/cli.py

@@ -206,7 +206,7 @@ def prettify(text):
     def sub(m):
         t = m.group(2)
         for ch in m.group(1):
-            t = {'C': cyan, '_': italic, '*': bold}[ch](t)
+            t = {'C': cyan, '_': italic, '*': bold, 'G': green, 'T': title}[ch](t)
         return t
 
     text = re.sub(r'[|]([a-zA-Z_*]+?) (.+?)[|]', sub, text)
@@ -263,17 +263,24 @@ def print_help_for_seq(seq, usage, message, appname):
         if leading_indent is None:
             leading_indent = indent
         j = '\n' + (' ' * indent)
-        a((' ' * leading_indent) + j.join(wrap(text, limit=linesz - indent)))
+        lines = []
+        for l in text.splitlines():
+            if l:
+                lines.extend(wrap(l, limit=linesz - indent))
+            else:
+                lines.append('')
+        a((' ' * leading_indent) + j.join(lines))
 
     usage = usage or '[program-to-run ...]'
     a('{}: {} [options] {}'.format(title('Usage'), bold(yellow(appname)), usage))
     a('')
     message = message or (
-        'Run the |_ {appname}| terminal emulator. You can also specify the |_ program| to run inside |_ {appname}| as normal'
+        'Run the |G {appname}| terminal emulator. You can also specify the |_ program| to run inside |_ {appname}| as normal'
         ' arguments following the |_ options|. For example: {appname} /bin/sh'
     ).format(appname=appname)
     wa(prettify(message))
     a('')
+    if seq:
         a('{}:'.format(title('Options')))
     for opt in seq:
         if isinstance(opt, str):

kitty/config.py

@@ -256,6 +256,7 @@ url_style.map = dict(((v, i) for i, v in enumerate('none single double curly'.sp
 
 
 type_map = {
+    'allow_remote_control': to_bool,
     'adjust_line_height': adjust_line_height,
     'scrollback_lines': positive_int,
     'scrollback_pager': shlex.split,

kitty/kitty.conf

@@ -153,6 +153,13 @@ open_url_with default
 # rectangular block with the mouse)
 rectangle_select_modifiers ctrl+alt
 
+
+# Allow other programs to control kitty. If you turn this on other programs can
+# control all aspects of kitty, including sending text to kitty windows,
+# opening new windows, closing windows, reading the content of windows, etc.
+# Note that this even works over ssh connections.
+allow_remote_control no
+
 # Choose whether to use the system implementation of wcwidth() (used to
 # control how many cells a character is rendered in).  If you use the system
 # implementation, then kitty and any programs running in it will agree. The

kitty/parser.c

@@ -727,6 +727,17 @@ dispatch_csi(Screen *screen, PyObject DUMP_UNUSED *dump_callback) {
 // }}}
 
 // DCS mode {{{
+
+static inline bool
+startswith(const uint32_t *string, size_t sz, const char *prefix) {
+    size_t l = strlen(prefix);
+    if (sz < l) return false;
+    for (size_t i = 0; i < l; i++) {
+        if (string[i] != (unsigned char)prefix[i]) return false;
+    }
+    return true;
+}
+
 static inline void
 dispatch_dcs(Screen *screen, PyObject DUMP_UNUSED *dump_callback) {
     if (screen->parser_buf_pos < 2) return;
@@ -739,11 +750,23 @@ dispatch_dcs(Screen *screen, PyObject DUMP_UNUSED *dump_callback) {
                     REPORT_OSC2(screen_request_capabilities, (char)screen->parser_buf[0], string);
                     screen_request_capabilities(screen, (char)screen->parser_buf[0], string);
                     Py_DECREF(string);
-                }
+                } else PyErr_Clear();
             } else {
                 REPORT_ERROR("Unrecognized DCS %c code: 0x%x", (char)screen->parser_buf[0], screen->parser_buf[1]);
             }
             break;
+        case '@':
+            if (startswith(screen->parser_buf + 1, screen->parser_buf_pos - 2, "kitty-cmd{")) {
+                PyObject *cmd = PyUnicode_FromKindAndData(PyUnicode_4BYTE_KIND, screen->parser_buf + 11, screen->parser_buf_pos - 11);
+                if (cmd != NULL) {
+                    REPORT_OSC2(screen_handle_cmd, (char)screen->parser_buf[0], cmd);
+                    screen_handle_cmd(screen, cmd);
+                    Py_DECREF(cmd);
+                } else PyErr_Clear();
+            } else {
+                REPORT_ERROR("Unrecognized DCS @ code: 0x%x", screen->parser_buf[1]);
+            }
+            break;
         default:
             REPORT_ERROR("Unrecognized DCS code: 0x%x", screen->parser_buf[0]);
             break;

kitty/remote_control.py

@@ -0,0 +1,73 @@
+#!/usr/bin/env python
+# vim:fileencoding=utf-8
+# License: GPL v3 Copyright: 2018, Kovid Goyal <kovid at kovidgoyal.net>
+
+import json
+import sys
+from functools import partial
+
+from kitty.cli import emph, parse_args
+from kitty.constants import appname, version
+
+
+def cmd(short_desc, desc=None, options_spec=None):
+
+    def w(func):
+        func.short_desc = short_desc
+        func.desc = desc or short_desc
+        func.name = func.__name__[4:]
+        func.options_spec = options_spec
+        return func
+    return w
+
+
+def parse_subcommand_cli(func, args):
+    opts, items = parse_args(args[1:], func.options_spec or '\n'.format, '...', func.desc, '{} @ {}'.format(appname, func.name))
+    return opts, items
+
+
+@cmd('List all windows')
+def cmd_ls(global_opts, opts, args):
+    pass
+
+
+global_options_spec = partial('''\
+
+'''.format, appname=appname)
+
+
+def main(args):
+    cmap = {k[4:]: v for k, v in globals().items() if k.startswith('cmd_')}
+    all_commands = tuple(sorted(cmap))
+    cmds = ('  |G {}|\n    {}'.format(cmap[c].name, cmap[c].short_desc) for c in all_commands)
+    msg = (
+        'Control {appname} by sending it commands. Add'
+        ' |_ allow_remote_control yes| to kitty.conf for this'
+        ' to work.\n\n|T Commands|:\n{cmds}\n\n'
+        'You can get help for each individual command by using:\n'
+        '{appname} @ |_ command| -h'
+    ).format(appname=appname, cmds='\n'.join(cmds))
+
+    global_opts, items = parse_args(args[1:], global_options_spec, 'command ...', msg, '{} @'.format(appname))
+
+    if not items:
+        raise SystemExit('You must specify a command')
+    cmd = items[0]
+    try:
+        func = cmap[cmd]
+    except KeyError:
+        raise SystemExit('{} is not a known command. Known commands are: {}'.format(
+            emph(cmd), ', '.join(all_commands)))
+    opts, items = parse_subcommand_cli(func, items)
+    payload = func(global_opts, opts, items)
+    send = {
+        'cmd': cmd,
+        'version': version,
+    }
+    if payload is not None:
+        send['payload'] = payload
+    send = ('@kitty-cmd' + json.dumps(send)).encode('ascii')
+    if not sys.stdout.isatty():
+        raise SystemExit('stdout is not a terminal')
+    sys.stdout.buffer.write(b'\x1bP' + send + b'\x1b\\')
+    sys.stdout.flush()

kitty/screen.c

@@ -1141,6 +1141,11 @@ set_color_table_color(Screen *self, unsigned int code, PyObject *color) {
     else { CALLBACK("set_color_table_color", "IO", code, color); }
 }
 
+void
+screen_handle_cmd(Screen *self, PyObject *cmd) {
+    CALLBACK("handle_remote_cmd", "O", cmd);
+}
+
 void
 screen_request_capabilities(Screen *self, char c, PyObject *q) {
     static char buf[128];

kitty/screen.h

@@ -106,6 +106,7 @@ void screen_delete_characters(Screen *self, unsigned int count);
 void screen_erase_characters(Screen *self, unsigned int count);
 void screen_set_margins(Screen *self, unsigned int top, unsigned int bottom);
 void screen_change_charset(Screen *, uint32_t to);
+void screen_handle_cmd(Screen *, PyObject *cmd);
 void screen_designate_charset(Screen *, uint32_t which, uint32_t as);
 void screen_use_latin1(Screen *, bool);
 void set_title(Screen *self, PyObject*);

kitty/window.py

@@ -2,6 +2,7 @@
 # vim:fileencoding=utf-8
 # License: GPL v3 Copyright: 2016, Kovid Goyal <kovid at kovidgoyal.net>
 
+import json
 import sys
 import weakref
 from collections import deque
@@ -258,6 +259,12 @@ class Window:
     def request_capabilities(self, q):
         self.screen.send_escape_code_to_child(DCS, get_capabilities(q))
 
+    def handle_remote_cmd(self, cmd):
+        get_boss().handle_remote_cmd(cmd, self)
+
+    def send_cmd_response(self, response):
+        self.screen.send_escape_code_to_child(DCS, '@kitty-cmd' + json.dumps(response))
+
     # }}}
 
     def text_for_selection(self):