path: root/drw.c

/* See LICENSE file for copyright and license details. */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <X11/Xlib.h>
#include <X11/Xft/Xft.h>

#include "drw.h"
#include "util.h"

#define UTF_INVALID 0xFFFD
#define UTF_SIZ     4

static const unsigned char utfbyte[UTF_SIZ + 1] = {0x80,    0, 0xC0, 0xE0, 0xF0};
static const unsigned char utfmask[UTF_SIZ + 1] = {0xC0, 0x80, 0xE0, 0xF0, 0xF8};
static const long utfmin[UTF_SIZ + 1] = {       0,    0,  0x80,  0x800,  0x10000};
static const long utfmax[UTF_SIZ + 1] = {0x10FFFF, 0x7F, 0x7FF, 0xFFFF, 0x10FFFF};

static long
utf8decodebyte(const char c, size_t *i)
{
	for (*i = 0; *i < (UTF_SIZ + 1); ++(*i))
		if (((unsigned char)c & utfmask[*i]) == utfbyte[*i])
			return (unsigned char)c & ~utfmask[*i];
	return 0;
}

static size_t
utf8validate(long *u, size_t i)
{
	if (!BETWEEN(*u, utfmin[i], utfmax[i]) || BETWEEN(*u, 0xD800, 0xDFFF))
		*u = UTF_INVALID;
	for (i = 1; *u > utfmax[i]; ++i)
		;
	return i;
}

static size_t
utf8decode(const char *c, long *u, size_t clen)
{
	size_t i, j, len, type;
	long udecoded;

	*u = UTF_INVALID;
	if (!clen)
		return 0;
	udecoded = utf8decodebyte(c[0], &len);
	if (!BETWEEN(len, 1, UTF_SIZ))
		return 1;
	for (i = 1, j = 1; i < clen && j < len; ++i, ++j) {
		udecoded = (udecoded << 6) | utf8decodebyte(c[i], &type);
		if (type)
			return j;
	}
	if (j < len)
		return 0;
	*u = udecoded;
	utf8validate(u, len);

	return len;
}

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);
	drw->fontcount = 0;
	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)
{
	size_t i;

	for (i = 0; i < drw->fontcount; i++)
		drw_font_free(drw->fonts[i]);
	XFreePixmap(drw->dpy, drw->drawable);
	XFreeGC(drw->dpy, drw->gc);
	free(drw);
}

/* This function is an implementation detail. Library users should use
 * drw_font_create instead.
 */
static Fnt *
drw_font_xcreate(Drw *drw, const char *fontname, FcPattern *fontpattern)
{
	Fnt *font;
	XftFont *xfont