ledit

commit 53f769b1d999f6964bc2431b316cf07a3b8166ec
parent feafabfe8d714cc8d08d0000a91a7a6e8baf8492
Author: lumidify <nobody@lumidify.org>
Date:   Thu,  7 Jul 2022 13:14:00 +0200

Check for XBufferOverflow when handling keys; misc fixes

Diffstat:
M
keys.c
 | 
49
++++++++++++++++++++++++++++++++++++++++++-------
M
keys.h
 | 
5
+++--
M
keys_basic.c
 | 
6
+++---
M
keys_command.c
 | 
8
+++++---
M
ledit.c
 | 
2
+-
M
leditrc.5
 | 
4
++--
M
leditrc.example
 | 
4
++--

7 files changed, 58 insertions(+), 20 deletions(-)
diff --git a/keys.c b/keys.c
@@ -19,16 +19,31 @@
 /* LockMask and Mod2Mask in particular are disabled (caps lock and numlock usually) */
 static unsigned int importantmod = ShiftMask | ControlMask | Mod1Mask | Mod3Mask | Mod4Mask | Mod5Mask;
 
+#define KEY_TEXT_INITIAL_SIZE 32
+static char *key_text = NULL;
+static size_t key_text_alloc = 0;
+
+void
+key_processing_cleanup(void) {
+	free(key_text);
+}
+
 int
 match_key(unsigned int mask, unsigned int state)
 {
 	return mask == XK_ANY_MOD || mask == (state & importantmod);
 }
 
+#ifdef X_HAVE_UTF8_STRING
+#define LOOKUP_STRING_FUNC Xutf8LookupString
+#else
+#define LOOKUP_STRING_FUNC XmbLookupString
+#endif
+
 void
 preprocess_key(
-    ledit_window *window, XEvent *event, KeySym *sym_ret,
-    char *buf_ret, int buf_size, int *buf_len_ret) {
+    ledit_window *window, XKeyEvent *event, KeySym *sym_ret,
+    char **buf_ret, int *buf_len_ret) {
 	/*
 	 * FIXME: I don't understand how key handling works with different keymaps.
 	 * If, for instance, you run "setxkbmap pk" and then type "Ctrl+c", the
@@ -52,9 +67,29 @@ preprocess_key(
 	 * keys don't use control in normal mode, and it just messes with all the
 	 * keys that do use control because ledit does its own mapping.
 	 */
-	event->xkey.state &= ~ControlMask;
-	/* FIXME: X_HAVE_UTF8_STRING See XmbLookupString(3) */
-	*buf_len_ret = Xutf8LookupString(
-	    window->xic, &event->xkey, buf_ret, buf_size, sym_ret, NULL
-	);
+	if (key_text_alloc == 0) {
+		key_text = ledit_malloc(KEY_TEXT_INITIAL_SIZE);
+		key_text_alloc = KEY_TEXT_INITIAL_SIZE;
+	}
+	event->state &= ~ControlMask;
+
+	int len = 0;
+	Status status;
+	if (window->xic && event->type == KeyPress) {
+		len = LOOKUP_STRING_FUNC(window->xic, event, key_text, key_text_alloc - 1, sym_ret, &status);
+		if (status == XBufferOverflow) {
+			key_text_alloc = ideal_array_size(key_text_alloc, len + 1);
+			key_text = ledit_realloc(key_text, key_text_alloc);
+			len = LOOKUP_STRING_FUNC(window->xic, event, key_text, key_text_alloc - 1, sym_ret, &status);
+		}
+	} else {
+		/* FIXME: anything equivalent to XBufferOverflow here? */
+		len = XLookupString(event, key_text, key_text_alloc - 1, sym_ret, NULL);
+		status = XLookupBoth;
+	}
+	*buf_len_ret = len >= (int)key_text_alloc ? (int)key_text_alloc - 1 : len;
+	key_text[*buf_len_ret] = '\0';
+	if (status != XLookupBoth && status != XLookupKeySym)
+		*sym_ret = NoSymbol;
+	*buf_ret = key_text;
 }
diff --git a/keys.h b/keys.h
@@ -15,9 +15,10 @@ int get_language_index(char *lang);
 int match_key(unsigned int mask, unsigned int state);
 /* preprocess key, i.e. get the KeySym and text corresponding to it */
 void preprocess_key(
-    ledit_window *window, XEvent *event, KeySym *sym_ret,
-    char *buf_ret, int buf_size, int *buf_len_ret
+    ledit_window *window, XKeyEvent *event, KeySym *sym_ret,
+    char **buf_ret, int *buf_len_ret
 );
+void key_processing_cleanup(void);
 
 /* FIXME: documentation */
 #define GEN_CB_MAP_HELPERS(name, typename, cmp_entry)                     \
diff --git a/keys_basic.c b/keys_basic.c
@@ -2622,12 +2622,12 @@ repeat_command(ledit_view *view, char *text, size_t len) {
 
 struct action
 basic_key_handler(ledit_view *view, XEvent *event, int lang_index) {
-	char buf[64];
-	KeySym sym;
+	char *buf = NULL;
+	KeySym sym = NoSymbol;
 	int n;
 
 	unsigned int key_state = event->xkey.state;
-	preprocess_key(view->window, event, &sym, buf, sizeof(buf), &n);
+	preprocess_key(view->window, &event->xkey, &sym, &buf, &n);
 
 	struct repetition_stack_elem *re = push_repetition_stack();
 	re->key_text = ledit_strndup(buf, (size_t)n);
diff --git a/keys_command.c b/keys_command.c
@@ -214,6 +214,8 @@ static int parse_range(
 );
 static int handle_cmd(ledit_view *view, char *cmd, size_t len, size_t lang_index);
 
+/* FIXME: USE LEN EVERYWHERE INSTEAD OF RELYING ON cmd BEING NUL-TERMINATED */
+/* FIXME: return error so write_quit knows when to quit */
 static int
 handle_write(ledit_view *view, char *cmd, size_t l1, size_t l2) {
 	(void)l1;
@@ -946,13 +948,13 @@ edit_discard(ledit_view *view, char *key_text, size_t len, size_t lang_index) {
 
 struct action
 command_key_handler(ledit_view *view, XEvent *event, int lang_index) {
-	char buf[64];
-	KeySym sym;
+	char *buf = NULL;
+	KeySym sym = NoSymbol;
 	int n;
 	command_key_array *cur_keys = config_get_command_keys(lang_index);
 	size_t num_keys = cur_keys->num_keys;
 	unsigned int key_state = event->xkey.state;
-	preprocess_key(view->window, event, &sym, buf, sizeof(buf), &n);
+	preprocess_key(view->window, &event->xkey, &sym, &buf, &n);
 	int grabkey = 1, found = 0;
 	command_key_cb_flags flags = KEY_FLAG_NONE;
 	for (size_t i = 0; i < num_keys; i++) {
diff --git a/ledit.c b/ledit.c
@@ -114,7 +114,6 @@ mainloop(void) {
 				change_kbd = 1;
 				continue;
 			}
-			/* FIXME: why None? */
 			if (XFilterEvent(&event, None))
 				continue;
 			ledit_view *view = NULL;
@@ -450,6 +449,7 @@ ledit_cleanup(void) {
 	search_cleanup();
 	basic_key_cleanup();
 	command_key_cleanup();
+	key_processing_cleanup();
 	if (buffer)
 		buffer_destroy(buffer);
 	config_cleanup(&common);
diff --git a/leditrc.5 b/leditrc.5
@@ -619,12 +619,12 @@ Note that this command works with soft lines, regardless of the current mode.
 .It Ar scroll-with-cursor-down Oo normal, insert Oc Oo num Oc
 Move
 .Ar num
-lines down, attemting to leave the cursor in its current line and character position.
+lines down, attempting to leave the cursor in its current line and character position.
 Note that this command works with soft lines, regardless of the current mode.
 .It Ar scroll-with-cursor-up Oo normal, insert Oc Oo num Oc
 Move
 .Ar num
-lines up, attemting to leave the cursor in its current line and character position.
+lines up, attempting to leave the cursor in its current line and character position.
 Note that this command works with soft lines, regardless of the current mode.
 .It Ar search-next Op normal, insert
 Move to the next search result.
diff --git a/leditrc.example b/leditrc.example
@@ -221,7 +221,7 @@ language-mapping = {
 		map "^" "^"
 	}
 	command-mapping = {
-		map "वग" "wq"
+		map "व‌" "wq"
 		map "व" "w"
 		map "‌" "q"
 		map "ड" "v"
@@ -293,7 +293,7 @@ language-mapping = {
 		map "^" "^"
 	}
 	command-mapping = {
-		map "وگ" "wq"
+		map "وق" "wq"
 		map "و" "w"
 		map "ق" "q"
 		map "ط" "v"