dmenu/drw.c
NRK 51e32d49b5 overhaul utf8decode()
this changes the utf8decode function to:

* report when an error occurs
* report how many bytes to advance on error

these will be useful in the next commit to render invalid utf8
sequences.

the new implementation is also shorter and more direct.
2024-07-14 11:42:55 +02:00

438 lines
11 KiB
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
static int
utf8decode(const char *s_in, long *u, int *err)
{
static const unsigned char lens[] = {
/* 0XXXX */ 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1,
/* 10XXX */ 0, 0, 0, 0, 0, 0, 0, 0, /* invalid */
/* 110XX */ 2, 2, 2, 2,
/* 1110X */ 3, 3,
/* 11110 */ 4,
/* 11111 */ 0, /* invalid */
};
static const unsigned char leading_mask[] = { 0x7F, 0x1F, 0x0F, 0x07 };
static const unsigned int overlong[] = { 0x0, 0x80, 0x0800, 0x10000 };
const unsigned char *s = (const unsigned char *)s_in;
int len = lens[*s >> 3];
*u = UTF_INVALID;
*err = 1;
if (len == 0)
return 1;
long cp = s[0] & leading_mask[len - 1];
for (int i = 1; i < len; ++i) {
if (s[i] == '\0' || (s[i] & 0xC0) != 0x80)
return i;
cp = (cp << 6) | (s[i] & 0x3F);
}
/* out of range, surrogate, overlong encoding */
if (cp > 0x10FFFF || (cp >> 11) == 0x1B || cp < overlong[len - 1])
return len;
*err = 0;
*u = cp;
return len;
}
Drw *
drw_create(Display *dpy, int screen, Window root, unsigned int w, unsigned int h)
{
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)
{
if (!drw)
return;
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);
drw_fontset_free(drw->fonts);
free(drw);
}
/* This function is an implementation detail. Library users should use
* drw_fontset_create instead.
*/
static Fnt *
xfont_create(Drw *drw, const char *fontname, FcPattern *fontpattern)
{
Fnt *font;
XftFont *xfont = NULL;
FcPattern *pattern = NULL;
if (fontname) {
/* Using the pattern found at font->xfont->pattern does not yield the
* same substitution results as using the pattern returned by
* FcNameParse; using the latter results in the desired fallback
* behaviour whereas the former just results in missing-character
* rectangles being drawn, at least with some fonts. */
if (!(xfont = XftFontOpenName(drw->dpy, drw->screen, fontname))) {
fprintf(stderr, "error, cannot load font from name: '%s'\n", fontname);
return NULL;
}
if (!(pattern = FcNameParse((FcChar8 *) fontname))) {
fprintf(stderr, "error, cannot parse font name to pattern: '%s'\n", fontname);
XftFontClose(drw->dpy, xfont);
return NULL;
}
} else if (fontpattern) {
if (!(xfont = XftFontOpenPattern(drw->dpy, fontpattern))) {
fprintf(stderr, "error, cannot load font from pattern.\n");
return NULL;
}
} else {
die("no font specified.");
}
font = ecalloc(1, sizeof(Fnt));
font->xfont = xfont;
font->pattern = pattern;
font->h = xfont->ascent + xfont->descent;
font->dpy = drw->dpy;
return font;
}
static void
xfont_free(Fnt *font)
{
if (!font)
return;
if (font->pattern)
FcPatternDestroy(font->pattern);
XftFontClose(font->dpy, font->xfont);
free(font);
}
Fnt*
drw_fontset_create(Drw* drw, const char *fonts[], size_t fontcount)
{
Fnt *cur, *ret = NULL;
size_t i;
if (!drw || !fonts)
return NULL;
for (i = 1; i <= fontcount; i++) {
if ((cur = xfont_create(drw, fonts[fontcount - i], NULL))) {
cur->next = ret;
ret = cur;
}
}
return (drw->fonts = ret);
}
void
drw_fontset_free(Fnt *font)
{
if (font) {
drw_fontset_free(font->next);
xfont_free(font);
}
}
void
drw_clr_create(Drw *drw, Clr *dest, const char *clrname)
{
if (!drw || !dest || !clrname)
return;
if (!XftColorAllocName(drw->dpy, DefaultVisual(drw->dpy, drw->screen),
DefaultColormap(drw->dpy, drw->screen),
clrname, dest))
die("error, cannot allocate color '%s'", 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;
/* need at least two colors for a scheme */
if (!drw || !clrnames || clrcount < 2 || !(ret = ecalloc(clrcount, sizeof(XftColor))))
return NULL;
for (i = 0; i < clrcount; i++)
drw_clr_create(drw, &ret[i], clrnames[i]);
return ret;
}
void
drw_setfontset(Drw *drw, Fnt *set)
{
if (drw)
drw->fonts = set;
}
void
drw_setscheme(Drw *drw, Clr *scm)
{
if (drw)
drw->scheme = scm;
}
void
drw_rect(Drw *drw, int x, int y, unsigned int w, unsigned int h, int filled, int invert)
{
if (!drw || !drw->scheme)
return;
XSetForeground(drw->dpy, drw->gc, invert ? drw->scheme[ColBg].pixel : drw->scheme[ColFg].pixel);
if (filled)
XFillRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w, h);
else
XDrawRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w - 1, h - 1);
}
int
drw_text(Drw *drw, int x, int y, unsigned int w, unsigned int h, unsigned int lpad, const char *text, int invert)
{
int ty, ellipsis_x = 0;
unsigned int tmpw, ew, ellipsis_w = 0, ellipsis_len, hash, h0, h1;
XftDraw *d = NULL;
Fnt *usedfont, *curfont, *nextfont;
int utf8strlen, utf8charlen, utf8err, render = x || y || w || h;
long utf8codepoint = 0;
const char *utf8str;
FcCharSet *fccharset;
FcPattern *fcpattern;
FcPattern *match;
XftResult result;
int charexists = 0, overflow = 0;
/* keep track of a couple codepoints for which we have no match. */
static unsigned int nomatches[128], ellipsis_width;
if (!drw || (render && (!drw->scheme || !w)) || !text || !drw->fonts)
return 0;
if (!render) {
w = invert ? invert : ~invert;
} else {
XSetForeground(drw->dpy, drw->gc, drw->scheme[invert ? ColFg : ColBg].pixel);
XFillRectangle(drw->dpy, drw->drawable, drw->gc, x, y, w, h);
d = XftDrawCreate(drw->dpy, drw->drawable,
DefaultVisual(drw->dpy, drw->screen),
DefaultColormap(drw->dpy, drw->screen));
x += lpad;
w -= lpad;
}
usedfont = drw->fonts;
if (!ellipsis_width && render)
ellipsis_width = drw_fontset_getwidth(drw, "...");
while (1) {
ew = ellipsis_len = utf8err = utf8charlen = utf8strlen = 0;
utf8str = text;
nextfont = NULL;
while (*text) {
utf8charlen = utf8decode(text, &utf8codepoint, &utf8err);
for (curfont = drw->fonts; curfont; curfont = curfont->next) {
charexists = charexists || XftCharExists(drw->dpy, curfont->xfont, utf8codepoint);
if (charexists) {
drw_font_getexts(curfont, text, utf8charlen, &tmpw, NULL);
if (ew + ellipsis_width <= w) {
/* keep track where the ellipsis still fits */
ellipsis_x = x + ew;
ellipsis_w = w - ew;
ellipsis_len = utf8strlen;
}
if (ew + tmpw > w) {
overflow = 1;
/* called from drw_fontset_getwidth_clamp():
* it wants the width AFTER the overflow
*/
if (!render)
x += tmpw;
else
utf8strlen = ellipsis_len;
} else if (curfont == usedfont) {
utf8strlen += utf8charlen;
text += utf8charlen;
ew += tmpw;
} else {
nextfont = curfont;
}
break;
}
}
if (overflow || !charexists || nextfont)
break;
else
charexists = 0;
}
if (utf8strlen) {
if (render) {
ty = y + (h - usedfont->h) / 2 + usedfont->xfont->ascent;
XftDrawStringUtf8(d, &drw->scheme[invert ? ColBg : ColFg],
usedfont->xfont, x, ty, (XftChar8 *)utf8str, utf8strlen);
}
x += ew;
w -= ew;
}
if (render && overflow)
drw_text(drw, ellipsis_x, y, ellipsis_w, h, 0, "...", invert);
if (!*text || overflow) {
break;
} else if (nextfont) {
charexists = 0;
usedfont = nextfont;
} else {
/* Regardless of whether or not a fallback font is found, the
* character must be drawn. */
charexists = 1;
hash = (unsigned int)utf8codepoint;
hash = ((hash >> 16) ^ hash) * 0x21F0AAAD;
hash = ((hash >> 15) ^ hash) * 0xD35A2D97;
h0 = ((hash >> 15) ^ hash) % LENGTH(nomatches);
h1 = (hash >> 17) % LENGTH(nomatches);
/* avoid expensive XftFontMatch call when we know we won't find a match */
if (nomatches[h0] == utf8codepoint || nomatches[h1] == utf8codepoint)
goto no_match;
fccharset = FcCharSetCreate();
FcCharSetAddChar(fccharset, utf8codepoint);
if (!drw->fonts->pattern) {
/* Refer to the comment in xfont_create for more information. */
die("the first font in the cache must be loaded from a font string.");
}
fcpattern = FcPatternDuplicate(drw->fonts->pattern);
FcPatternAddCharSet(fcpattern, FC_CHARSET, fccharset);
FcPatternAddBool(fcpattern, FC_SCALABLE, FcTrue);
FcConfigSubstitute(NULL, fcpattern, FcMatchPattern);
FcDefaultSubstitute(fcpattern);
match = XftFontMatch(drw->dpy, drw->screen, fcpattern, &result);
FcCharSetDestroy(fccharset);
FcPatternDestroy(fcpattern);
if (match) {
usedfont = xfont_create(drw, NULL, match);
if (usedfont && XftCharExists(drw->dpy, usedfont->xfont, utf8codepoint)) {
for (curfont = drw->fonts; curfont->next; curfont = curfont->next)
; /* NOP */
curfont->next = usedfont;
} else {
xfont_free(usedfont);
nomatches[nomatches[h0] ? h1 : h0] = utf8codepoint;
no_match:
usedfont = drw->fonts;
}
}
}
}
if (d)
XftDrawDestroy(d);
return x + (render ? w : 0);
}
void
drw_map(Drw *drw, Window win, int x, int y, unsigned int w, unsigned int h)
{
if (!drw)
return;
XCopyArea(drw->dpy, drw->drawable, win, drw->gc, x, y, w, h, x, y);
XSync(drw->dpy, False);
}
unsigned int
drw_fontset_getwidth(Drw *drw, const char *text)
{
if (!drw || !drw->fonts || !text)
return 0;
return drw_text(drw, 0, 0, 0, 0, 0, text, 0);
}
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)
{
XGlyphInfo ext;
if (!font || !text)
return;
XftTextExtentsUtf8(font->dpy, font->xfont, (XftChar8 *)text, len, &ext);
if (w)
*w = ext.xOff;
if (h)
*h = font->h;
}
Cur *
drw_cur_create(Drw *drw, int shape)
{
Cur *cur;
if (!drw || !(cur = ecalloc(1, sizeof(Cur))))
return NULL;
cur->cursor = XCreateFontCursor(drw->dpy, shape);
return cur;
}
void
drw_cur_free(Drw *drw, Cur *cursor)
{
if (!cursor)
return;
XFreeCursor(drw->dpy, cursor->cursor);
free(cursor);
}