Adding input method patch (#31)

Adding input method patch ref. PR #22

README.md

@@ -28,6 +28,8 @@ Browsing patches? There is a [map of patches](https://coggle.it/diagram/YjT2DD6j
 
 ### Changelog:
 
+2024-07-17 - Added the input method patch
+
 2024-07-16 - Added the mouse motion support patch
 
 2023-06-15 - Added the caret width patch
@@ -138,6 +140,9 @@ Browsing patches? There is a [map of patches](https://coggle.it/diagram/YjT2DD6j
    - [initialtext](https://tools.suckless.org/dmenu/patches/initialtext/)
       - adds an option to provide preselected text
 
+   - input-method
+      - adds support for input methods (fctix, ibus, etc.)
+
    - [instant](https://tools.suckless.org/dmenu/patches/instant/)
       - adds a flag that will cause dmenu to select an item immediately if there is only one
         matching option left

dmenu.c

@@ -269,6 +269,9 @@ cleanup(void)
 	size_t i;
 
 	XUngrabKey(dpy, AnyKey, AnyModifier, root);
+	#if INPUTMETHOD_PATCH
+	XSetInputFocus(dpy, root, RevertToPointerRoot, CurrentTime);
+	#endif // INPUTMETHOD_PATCH
 	for (i = 0; i < SchemeLast; i++)
 		free(scheme[i]);
 	for (i = 0; items && items[i].text; ++i)
@@ -1505,7 +1508,6 @@ run(void)
 	#if PRESELECT_PATCH
 	int i;
 	#endif // PRESELECT_PATCH
-
 	while (!XNextEvent(dpy, &ev)) {
 		#if PRESELECT_PATCH
 		if (preselected) {
@@ -1519,8 +1521,15 @@ run(void)
 			preselected = 0;
 		}
 		#endif // PRESELECT_PATCH
+		#if INPUTMETHOD_PATCH
+		if (XFilterEvent(&ev, None))
+			continue;
+		if (composing)
+			continue;
+		#else
 		if (XFilterEvent(&ev, win))
 			continue;
+		#endif // INPUTMETHOD_PATCH
 		switch(ev.type) {
 		#if MOUSE_SUPPORT_PATCH
 		case ButtonPress:
@@ -1787,13 +1796,16 @@ setup(void)
 			(unsigned char *) &dock, 1);
 	#endif // WMTYPE_PATCH
 
-
 	/* input methods */
 	if ((xim = XOpenIM(dpy, NULL, NULL, NULL)) == NULL)
 		die("XOpenIM failed: could not open input device");
 
+	#if INPUTMETHOD_PATCH
+	init_input_method(xim);
+	#else
 	xic = XCreateIC(xim, XNInputStyle, XIMPreeditNothing | XIMStatusNothing,
 	                XNClientWindow, win, XNFocusWindow, win, NULL);
+	#endif // INPUTMETHOD_PATCH
 
 	#if MANAGED_PATCH
 	if (managed) {
@@ -1815,8 +1827,13 @@ setup(void)
 				XSelectInput(dpy, dws[i], FocusChangeMask);
 			XFree(dws);
 		}
+		#if !INPUTMETHOD_PATCH
 		grabfocus();
+		#endif // INPUTMETHOD_PATCH
 	}
+	#if INPUTMETHOD_PATCH
+	grabfocus();
+	#endif // INPUTMETHOD_PATCH
 	drw_resize(drw, mw, mh);
 	drawmenu();
 }
@@ -1932,6 +1949,10 @@ main(int argc, char *argv[])
 	#if XRESOURCES_PATCH
 	if (!setlocale(LC_CTYPE, "") || !XSupportsLocale())
 		fputs("warning: no locale support\n", stderr);
+	#if INPUTMETHOD_PATCH
+	if (!XSetLocaleModifiers(""))
+		fputs("warning: could not set locale modifiers", stderr);
+	#endif // INPUTMETHOD_PATCH
 	if (!(dpy = XOpenDisplay(NULL)))
 		die("cannot open display");
 
@@ -2164,6 +2185,10 @@ main(int argc, char *argv[])
 	#else // !XRESOURCES_PATCH
 	if (!setlocale(LC_CTYPE, "") || !XSupportsLocale())
 		fputs("warning: no locale support\n", stderr);
+	#if INPUTMETHOD_PATCH
+	if (!XSetLocaleModifiers(""))
+		fputs("warning: could not set locale modifiers", stderr);
+	#endif // INPUTMETHOD_PATCH
 	if (!(dpy = XOpenDisplay(NULL)))
 		die("cannot open display");
 	screen = DefaultScreen(dpy);

patch/include.c

@@ -13,6 +13,9 @@
 #if HIGHPRIORITY_PATCH
 #include "highpriority.c"
 #endif
+#if INPUTMETHOD_PATCH
+#include "inputmethod.c"
+#endif
 #if DYNAMIC_OPTIONS_PATCH
 #include "dynamicoptions.c"
 #endif

patch/include.h

@@ -4,6 +4,9 @@
 #if FZFEXPECT_PATCH
 #include "fzfexpect.h"
 #endif
+#if INPUTMETHOD_PATCH
+#include "inputmethod.h"
+#endif
 #if MULTI_SELECTION_PATCH
 #include "multiselect.h"
 #endif

patch/inputmethod.c

@@ -0,0 +1,196 @@
+static size_t nextrunetext(const char *text, size_t position, int inc)
+{
+	ssize_t n;
+
+	/* return location of next utf8 rune in the given direction (+1 or -1) */
+	for (n = position + inc; n + inc >= 0 && (text[n] & 0xc0) == 0x80; n += inc)
+		;
+	return n;
+}
+
+/* return bytes from beginning of text to nth utf8 rune to the right */
+static size_t runebytes(const char *text, size_t n)
+{
+	size_t ret;
+
+	ret = 0;
+	while (n-- > 0)
+		ret += nextrunetext(text + ret, 0, 1);
+	return ret;
+}
+
+/* return number of characters from beginning of text to nth byte to the right
+ */
+static size_t runechars(const char *text, size_t n)
+{
+	size_t ret, i;
+
+	ret = i = 0;
+	while (i < n) {
+		i += nextrunetext(text + i, 0, 1);
+		ret++;
+	}
+	return ret;
+}
+
+/* move caret on pre-edit text */
+static void preeditcaret(XIC xic, XPointer clientdata, XPointer calldata)
+{
+	XIMPreeditCaretCallbackStruct *pcaret;
+
+	(void)xic;
+	pcaret = (XIMPreeditCaretCallbackStruct *)calldata;
+	if (!pcaret)
+		return;
+	switch (pcaret->direction) {
+	case XIMForwardChar:
+		cursor = nextrune(+1);
+		break;
+	case XIMBackwardChar:
+		cursor = nextrune(-1);
+		break;
+	case XIMForwardWord:
+		movewordedge(+1);
+		break;
+	case XIMBackwardWord:
+		movewordedge(-1);
+		break;
+	case XIMLineStart:
+		cursor = 0;
+		break;
+	case XIMLineEnd:
+		if (preview[cursor] != '\0')
+			cursor = strlen(preview);
+		break;
+	case XIMAbsolutePosition:
+		cursor = runebytes(text, pcaret->position);
+		break;
+	case XIMDontChange:
+		/* do nothing */
+		break;
+	case XIMCaretUp:
+	case XIMCaretDown:
+	case XIMNextLine:
+	case XIMPreviousLine:
+		/* not implemented */
+		break;
+	}
+	pcaret->position = runechars(preview, cursor);
+}
+
+/* start input method pre-editing */
+static int preeditstart(XIC xic, XPointer clientdata, XPointer calldata)
+{
+	(void)xic;
+	(void)calldata;
+	(void)clientdata;
+	composing = 1;
+	printf("PREEDIT\n");
+	return BUFSIZ;
+}
+
+/* end input method pre-editing */
+static void preeditdone(XIC xic, XPointer clientdata, XPointer calldata)
+{
+	(void)xic;
+	(void)clientdata;
+	(void)calldata;
+	printf("DONE\n");
+
+	composing = 0;
+}
+
+/* draw input method pre-edit text */
+static void preeditdraw(XIC xic, XPointer clientdata, XPointer calldata)
+{
+	XIMPreeditDrawCallbackStruct *pdraw;
+	size_t beg, dellen, inslen, endlen;
+
+	printf("DRAW\n");
+
+	(void)xic;
+	pdraw = (XIMPreeditDrawCallbackStruct *)calldata;
+	if (!pdraw)
+		return;
+
+	/* we do not support wide characters */
+	if (pdraw->text && pdraw->text->encoding_is_wchar == True) {
+		fputs("warning: wchar is not supportecd; use utf8", stderr);
+		return;
+	}
+
+	beg = runebytes(text, pdraw->chg_first);
+	dellen = runebytes(preview + beg, pdraw->chg_length);
+	inslen = pdraw->text ? runebytes(pdraw->text->string.multi_byte, pdraw->text->length) : 0;
+	endlen = 0;
+	if (beg + dellen < strlen(preview))
+		endlen = strlen(preview + beg + dellen);
+
+	/* we cannot change text past the end of our pre-edit string */
+
+	if (beg + dellen >= BUFSIZ || beg + inslen >= BUFSIZ)
+		return;
+
+	/* get space for text to be copied, and copy it */
+	memmove(preview + beg + inslen, preview + beg + dellen, endlen + 1);
+	if (pdraw->text && pdraw->text->length)
+		memcpy(preview + beg, pdraw->text->string.multi_byte, inslen);
+	(preview + beg + inslen + endlen)[0] = '\0';
+
+	/* get caret position */
+	cursor = runebytes(text, pdraw->caret);
+}
+
+static void init_input_method(XIM xim)
+{
+	XVaNestedList preedit = NULL;
+	XICCallback start, done, draw, caret;
+	XIMStyle preeditstyle;
+	XIMStyle statusstyle;
+	XIMStyles *imstyles;
+	int i;
+
+	/* get styles supported by input method */
+	if (XGetIMValues(xim, XNQueryInputStyle, &imstyles, NULL) != NULL)
+		fputs("XGetIMValues: could not obtain input method values", stderr);
+
+	/* check whether input method support on-the-spot pre-editing */
+	preeditstyle = XIMPreeditNothing;
+	statusstyle = XIMStatusNothing;
+	for (i = 0; i < imstyles->count_styles; i++) {
+		if (imstyles->supported_styles[i] & XIMPreeditCallbacks) {
+			preeditstyle = XIMPreeditCallbacks;
+			break;
+		}
+	}
+
+	/* create callbacks for the input context */
+	start.client_data = NULL;
+	done.client_data = NULL;
+	draw.client_data = (XPointer)text;
+	caret.client_data = (XPointer)text;
+	start.callback = (XICProc)preeditstart;
+	done.callback = (XICProc)preeditdone;
+	draw.callback = (XICProc)preeditdraw;
+	caret.callback = (XICProc)preeditcaret;
+
+	/* create list of values for input context */
+	preedit = XVaCreateNestedList(0, XNPreeditStartCallback, &start, XNPreeditDoneCallback,
+				      &done, XNPreeditDrawCallback, &draw, XNPreeditCaretCallback,
+				      &caret, NULL);
+	if (preedit == NULL)
+		fputs("XVaCreateNestedList: could not create nested list", stderr);
+
+	xic = XCreateIC(xim, XNInputStyle, preeditstyle | statusstyle, XNPreeditAttributes, preedit,
+			XNClientWindow, win, XNFocusWindow, win, NULL);
+	XFree(preedit);
+
+	long eventmask;
+	/* get events the input method is interested in */
+	if (XGetICValues(xic, XNFilterEvents, &eventmask, NULL))
+		fputs("XGetICValues: could not obtain input context values", stderr);
+
+	XSelectInput(dpy, win,
+		     ExposureMask | KeyPressMask | VisibilityChangeMask | ButtonPressMask |
+			     PointerMotionMask | eventmask);
+}

patch/inputmethod.h

@@ -0,0 +1,11 @@
+static int composing;
+static char preview[512] = "";
+
+static size_t nextrunetext(const char *text, size_t position, int inc);
+static size_t runebytes(const char *text, size_t n);
+static size_t runechars(const char *text, size_t n);
+static void preeditcaret(XIC xic, XPointer clientdata, XPointer calldata);
+static int preeditstart(XIC xic, XPointer clientdata, XPointer calldata);
+static void preeditdone(XIC xic, XPointer clientdata, XPointer calldata);
+static void preeditdraw(XIC xic, XPointer clientdata, XPointer calldata);
+static void init_input_method(XIM xim);

patches.def.h

@@ -108,6 +108,12 @@
  */
 #define INITIALTEXT_PATCH 0
 
+/* Adds support for input methods (fctix, ibus, etc.) allowing the user to change the
+ * keyboard layout while dmenu is open.
+ * https://github.com/bakkeby/dmenu-flexipatch/pull/22
+ */
+#define INPUTMETHOD_PATCH 0
+
 /* This patch adds a flag which will cause dmenu to select an item immediately if there
  * is only one matching option left.
  * https://tools.suckless.org/dmenu/patches/instant/