libsl

commit b82ef25d40d29b93d4f9a2fd2a646670f5ea6fd6
parent e8224f0f3dea1c6945bb283bee1d3eb2f981597b
Author: Hiltjo Posthuma <hiltjo@codemadness.org>
Date:   Sat, 27 Sep 2025 12:27:20 +0200

add x11 "backend"

This code is based of older dwm and dmenu versions which didn't use Xft with
some modifications for the newer interface.

It was one of the goals of libsl: to support multiple backends for X11.

Diffstat:
A
x11/drw.c
 | 
289
++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
A
x11/drw.h
 | 
61
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

2 files changed, 350 insertions(+), 0 deletions(-)
diff --git a/x11/drw.c b/x11/drw.c
@@ -0,0 +1,289 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <X11/Xlib.h>
+
+#include "drw.h"
+#include "util.h"
+
+Drw *
+drw_create(Display *dpy, int screen, Window root, unsigned int w, unsigned int h)
+{
+	Drw *drw;
+
+	drw = ecalloc(1, sizeof(Drw));
+	drw->dpy = dpy;
+	drw->screen = screen;
+	drw->root = root;
+	drw->w = w;
+	drw->h = h;
+	drw->drawable = XCreatePixmap(dpy, root, w, h, DefaultDepth(dpy, screen));
+	drw->gc = XCreateGC(dpy, root, 0, NULL);
+	XSetLineAttributes(dpy, drw->gc, 1, LineSolid, CapButt, JoinMiter);
+
+	return drw;
+}
+
+void
+drw_resize(Drw *drw, unsigned int w, unsigned int h)
+{
+	drw->w = w;
+	drw->h = h;
+	if (drw->drawable)
+		XFreePixmap(drw->dpy, drw->drawable);
+	drw->drawable = XCreatePixmap(drw->dpy, drw->root, w, h, DefaultDepth(drw->dpy, drw->screen));
+}
+
+void
+drw_free(Drw *drw)
+{
+	XFreePixmap(drw->dpy, drw->drawable);
+	XFreeGC(drw->dpy, drw->gc);
+	free(drw);
+}
+
+static Fnt *
+xfont_create(Display *dpy, const char *fontname)
+{
+	Fnt *font;
+	XFontStruct **xfonts;
+	char **font_names;
+	char *def, **missing;
+	int n;
+
+	font = ecalloc(1, sizeof(Fnt));
+	font->dpy = dpy;
+	font->set = XCreateFontSet(dpy, fontname, &missing, &n, &def);
+	if (missing) {
+		while (n--)
+			fprintf(stderr, "drw: missing fontset: %s\n", missing[n]);
+		XFreeStringList(missing);
+	}
+	if (font->set) {
+		XExtentsOfFontSet(font->set);
+		n = XFontsOfFontSet(font->set, &xfonts, &font_names);
+		while (n--) {
+			font->ascent = MAX(font->ascent, (*xfonts)->ascent);
+			font->descent = MAX(font->descent,(*xfonts)->descent);
+			xfonts++;
+		}
+	} else {
+		if (!(font->xfont = XLoadQueryFont(dpy, fontname))
+		&& !(font->xfont = XLoadQueryFont(dpy, "fixed")))
+			die("error, cannot load font: '%s'\n", fontname);
+		font->ascent = font->xfont->ascent;
+		font->descent = font->xfont->descent;
+	}
+	font->h = font->ascent + font->descent;
+
+	return font;
+}
+
+void
+xfont_free(Display *dpy, Fnt *font)
+{
+	if (font->set)
+		XFreeFontSet(dpy, font->set);
+	else
+		XFreeFont(dpy, font->xfont);
+	free(font);
+}
+
+Fnt *
+drw_fontset_create(Drw* drw, const char *fonts[], size_t fontcount)
+{
+	/* just create using first font */
+	/* TODO: more? */
+	drw->fonts = xfont_create(drw->dpy, fonts[0]);
+	return drw->fonts;
+}
+
+void
+drw_fontset_free(Fnt *font)
+{
+	xfont_free(font->dpy, font);
+}
+
+void
+drw_clr_create(Drw *drw, Clr *dest, const char *clrname)
+{
+	Colormap cmap;
+	XColor ecolor;
+
+	cmap = DefaultColormap(drw->dpy, drw->screen);
+	if (!XAllocNamedColor(drw->dpy, cmap, clrname, dest, &ecolor))
+		die("error, cannot allocate color '%s'\n", clrname);
+}
+
+/* Wrapper to create color schemes. The caller has to call free(3) on the
+ * returned color scheme when done using it. */
+Clr *
+drw_scm_create(Drw *drw, const char *clrnames[], size_t clrcount)
+{
+	size_t i;
+	Clr *ret;
+
+	ret = ecalloc(clrcount, sizeof(Clr));
+	for (i = 0; i < clrcount; i++)
+		drw_clr_create(drw, &ret[i], clrnames[i]);
+
+	return ret;
+}
+
+void
+drw_clr_free(Drw *drw, Clr *c)
+{
+	if (!drw || !c)
+		return;
+
+	/* c is typedef XColor Clr */
+	/* TODO: free XColor? */
+}
+
+void
+drw_scm_free(Drw *drw, Clr *scm, size_t clrcount)
+{
+	size_t i;
+
+	if (!drw || !scm)
+		return;
+
+	for (i = 0; i < clrcount; i++)
+		drw_clr_free(drw, &scm[i]);
+}
+
+void
+drw_setfontset(Drw *drw, Fnt *set)
+{
+	drw->fonts = set;
+}
+
+void
+drw_setscheme(Drw *drw, Clr *scheme)
+{
+	drw->scheme = scheme;
+}
+
+void
+drw_rect(Drw *drw, int x, int y, unsigned int w, unsigned int h, int filled,
+	int invert)
+{
+	XSetForeground(drw->dpy, drw->gc, drw->scheme[invert ? ColBg : ColFg].pixel);
+	if (filled)
+		XFillRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w + 1, h + 1);
+	else
+		XDrawRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w, h);
+}
+
+int
+drw_text(Drw *drw, int x, int y, unsigned int w, unsigned int h, unsigned int lpad,
+	const char *text, int invert)
+{
+	char buf[256];
+	int i, tx, ty, th, len, olen, render = x || y || w || h;
+	unsigned int texw, texh;
+
+	if (!render) {
+		w = ~w;
+	} else {
+		XSetForeground(drw->dpy, drw->gc, drw->scheme[invert ? ColFg : ColBg].pixel);
+		XFillRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w, h);
+		x += lpad;
+		w -= lpad;
+	}
+
+	olen = strlen(text);
+	drw_font_getexts(drw->fonts, text, olen, &texw, &texh);
+	th = drw->fonts->ascent + drw->fonts->descent;
+	ty = y + (h / 2) - (th / 2) + drw->fonts->ascent;
+	tx = x;
+	/* shorten text if necessary */
+	for (len = MIN(olen, sizeof buf); len && texw > w; len--)
+		drw_font_getexts(drw->fonts, text, len, &texw, &texh);
+	if (!len)
+		return x;
+	memcpy(buf, text, len);
+	if (len < olen)
+		for (i = len; i && i > len - 3; buf[--i] = '.')
+			;
+	XSetForeground(drw->dpy, drw->gc, invert ? drw->scheme[ColBg].pixel : drw->scheme[ColFg].pixel);
+	if (drw->fonts->set)
+		XmbDrawString(drw->dpy, drw->drawable, drw->fonts->set, drw->gc, tx, ty, buf, len);
+	else
+		XDrawString(drw->dpy, drw->drawable, drw->gc, tx, ty, buf, len);
+
+	x += texw;
+	w -= texw;
+
+	return x + (render ? w : 0);
+}
+
+void
+drw_map(Drw *drw, Window win, int x, int y, unsigned int w, unsigned int h)
+{
+	XCopyArea(drw->dpy, drw->drawable, win, drw->gc, x, y, w, h, x, y);
+	XSync(drw->dpy, False);
+}
+
+static unsigned int
+drw_font_getexts_width(Fnt *font, const char *text, unsigned int len)
+{
+	unsigned int w;
+
+	drw_font_getexts(font, text, len, &w, NULL);
+
+	return w;
+}
+
+unsigned int
+drw_fontset_getwidth(Drw *drw, const char *text)
+{
+	return drw_font_getexts_width(drw->fonts, text, strlen(text));
+}
+
+unsigned int
+drw_fontset_getwidth_clamp(Drw *drw, const char *text, unsigned int n)
+{
+	unsigned int tmp = 0;
+	if (drw && drw->fonts && text && n)
+		tmp = drw_text(drw, 0, 0, 0, 0, 0, text, n);
+	return MIN(n, tmp);
+}
+
+void
+drw_font_getexts(Fnt *font, const char *text, unsigned int len, unsigned int *w, unsigned int *h)
+{
+	XRectangle r;
+
+	if (font->set) {
+		XmbTextExtents(font->set, text, len, NULL, &r);
+		if (w)
+			*w = r.width;
+		if (h)
+			*h = r.height;
+	} else {
+		if (w)
+			*w = XTextWidth(font->xfont, text, len);
+		if (h)
+			*h = font->ascent + font->descent;
+	}
+}
+
+Cur *
+drw_cur_create(Drw *drw, int shape)
+{
+	Cur *cur;
+
+	cur = ecalloc(1, sizeof(Cur));
+	cur->cursor = XCreateFontCursor(drw->dpy, shape);
+
+	return cur;
+}
+
+void
+drw_cur_free(Drw *drw, Cur *cursor)
+{
+	XFreeCursor(drw->dpy, cursor->cursor);
+	free(cursor);
+}
diff --git a/x11/drw.h b/x11/drw.h
@@ -0,0 +1,61 @@
+/* See LICENSE file for copyright and license details. */
+
+typedef struct {
+	Cursor cursor;
+} Cur;
+
+typedef struct {
+	Display *dpy;
+	int ascent;
+	int descent;
+	unsigned int h;
+	XFontSet set;
+	XFontStruct *xfont;
+} Fnt;
+
+enum { ColFg, ColBg, ColBorder }; /* Clr scheme index */
+typedef XColor Clr;
+
+typedef struct {
+	unsigned int w, h;
+	Display *dpy;
+	int screen;
+	Window root;
+	Drawable drawable;
+	GC gc;
+	Clr *scheme;
+	Fnt *fonts;
+} Drw;
+
+/* Drawable abstraction */
+Drw *drw_create(Display *dpy, int screen, Window win, unsigned int w, unsigned int h);
+void drw_resize(Drw *drw, unsigned int w, unsigned int h);
+void drw_free(Drw *drw);
+
+/* Fnt abstraction */
+Fnt *drw_fontset_create(Drw* drw, const char *fonts[], size_t fontcount);
+void drw_fontset_free(Fnt* set);
+unsigned int drw_fontset_getwidth(Drw *drw, const char *text);
+unsigned int drw_fontset_getwidth_clamp(Drw *drw, const char *text, unsigned int n);
+void drw_font_getexts(Fnt *font, const char *text, unsigned int len, unsigned int *w, unsigned int *h);
+
+/* Colorscheme abstraction */
+void drw_clr_create(Drw *drw, Clr *dest, const char *clrname);
+void drw_clr_free(Drw *drw, Clr *c);
+Clr *drw_scm_create(Drw *drw, const char *clrnames[], size_t clrcount);
+void drw_scm_free(Drw *drw, Clr *scm, size_t clrcount);
+
+/* Cursor abstraction */
+Cur *drw_cur_create(Drw *drw, int shape);
+void drw_cur_free(Drw *drw, Cur *cursor);
+
+/* Drawing context manipulation */
+void drw_setfontset(Drw *drw, Fnt *set);
+void drw_setscheme(Drw *drw, Clr *scm);
+
+/* Drawing functions */
+void drw_rect(Drw *drw, int x, int y, unsigned int w, unsigned int h, int filled, int invert);
+int drw_text(Drw *drw, int x, int y, unsigned int w, unsigned int h, unsigned int lpad, const char *text, int invert);
+
+/* Map functions */
+void drw_map(Drw *drw, Window win, int x, int y, unsigned int w, unsigned int h);