Implement DCS querying of terminfo data

kitty/boss.py

@@ -24,6 +24,7 @@ from .utils import sanitize_title
 from .fast_data_types import (
     BRACKETED_PASTE_START, BRACKETED_PASTE_END, Screen, read_bytes_dump, read_bytes
 )
+from .terminfo import get_capabilities
 
 
 def handle_unix_signals():
@@ -246,7 +247,9 @@ class Boss(Thread):
 
     def set_dynamic_color(self, code, value):
         wmap = {10: 'fg', 11: 'bg', 110: 'fg', 111: 'bg'}
-        for val in value.decode('utf-8').split(';'):
+        if isinstance(value, bytes):
+            value = value.decode('utf-8')
+        for val in value.split(';'):
             w = wmap.get(code)
             if w is not None:
                 if code >= 110:
@@ -260,6 +263,9 @@ class Boss(Thread):
         self.pending_color_changes = {}
         glfw.glfwPostEmptyEvent()
 
+    def request_capabilities(self, q):
+        self.write_to_child(get_capabilities(q))
+
     # actions {{{
 
     def paste(self, text):

kitty/data-types.c

@@ -51,6 +51,7 @@ PyInit_fast_data_types(void) {
         PyModule_AddIntConstant(m, "DECORATION", DECORATION_SHIFT);
         PyModule_AddStringMacro(m, BRACKETED_PASTE_START);
         PyModule_AddStringMacro(m, BRACKETED_PASTE_END);
+        PyModule_AddStringMacro(m, ERROR_PREFIX);
         PyModule_AddIntMacro(m, CURSOR_BLOCK);
         PyModule_AddIntMacro(m, CURSOR_BEAM);
         PyModule_AddIntMacro(m, CURSOR_UNDERLINE);

kitty/data-types.h

@@ -21,6 +21,9 @@ typedef uint64_t color_type;
 typedef uint32_t decoration_type;
 typedef uint32_t combining_type;
 typedef unsigned int index_type;
+
+#define ERROR_PREFIX "[PARSE ERROR]"
+
 #define CELL_SIZE (sizeof(char_type) + sizeof(color_type) + sizeof(decoration_type) + sizeof(combining_type))
 // The data cell size must be a multiple of 3
 #define DATA_CELL_SIZE 2 * 3

kitty/parser.c

@@ -76,7 +76,7 @@ static void _report_error(PyObject *dump_callback, const char *fmt, ...) {
 
 #define DUMP_UNUSED UNUSED
 
-#define REPORT_ERROR(...) fprintf(stderr, "[PARSE ERROR] "); fprintf(stderr, __VA_ARGS__); fprintf(stderr, "\n");
+#define REPORT_ERROR(...) fprintf(stderr, "%s ", ERROR_PREFIX); fprintf(stderr, __VA_ARGS__); fprintf(stderr, "\n");
 
 #define REPORT_COMMAND(...)
 #define REPORT_DRAW(ch)

kitty/terminfo.py

@@ -2,6 +2,8 @@
 # vim:fileencoding=utf-8
 # License: GPL v3 Copyright: 2016, Kovid Goyal <kovid at kovidgoyal.net>
 
+from binascii import unhexlify, hexlify
+
 names = 'xterm-kitty', 'KovIdTTY'
 
 termcap_aliases = {
@@ -264,7 +266,7 @@ termcap_aliases.update({
     'SF': 'indn',
     # 'Ic': 'initc',
     # 'mk': 'invis',
-    'bs': 'kbs',
+    'kb': 'kbs',
     'kl': 'kcub1',
     'kd': 'kcud1',
     'kr': 'kcuf1',
@@ -318,6 +320,8 @@ termcap_aliases.update({
 
 })
 
+queryable_capabilities = numeric_capabilities.copy()
+queryable_capabilities.update(string_capabilities)
 extra = (bool_capabilities | numeric_capabilities.keys() | string_capabilities.keys()) - set(termcap_aliases.values())
 if extra:
     raise Exception('Termcap aliases not complete, missing: {}'.format(extra))
@@ -335,3 +339,26 @@ def generate_terminfo():
 def key_as_bytes(name):
     ans = string_capabilities[name]
     return ans.replace(r'\E', '\033').encode('ascii')
+
+
+def get_capabilities(query_string):
+    from .fast_data_types import ERROR_PREFIX
+    ans = []
+    try:
+        for q in query_string.split(';'):
+            name = unhexlify(q).decode('utf-8')
+            if name == 'TN':
+                val = names[0]
+            else:
+                try:
+                    val = queryable_capabilities[name]
+                except KeyError:
+                    try:
+                        val = queryable_capabilities[termcap_aliases[name]]
+                    except Exception as e:
+                        print(ERROR_PREFIX, 'Unknown terminfo property:', name)
+                        raise
+            ans.append(q + '=' + hexlify(str(val)))
+        return b'\033P1+r' + ';'.join(ans).encode('utf-8') + b'\033\\'
+    except Exception:
+        return b'\033P0+r' + query_string.encode('utf-8') + b'\033\\'