1 files changed, 450 insertions, 0 deletions

diff --git a/drw.c b/drw.c
new file mode 100644
index 0000000..a58a2b4
--- /dev/null
+++ b/drw.c
@@ -0,0 +1,450 @@
+/* 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 = 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 i, ty, ellipsis_x = 0;
+        unsigned int tmpw, ew, ellipsis_w = 0, ellipsis_len;
+        XftDraw *d = NULL;
+        Fnt *usedfont, *curfont, *nextfont;
+        int utf8strlen, utf8charlen, 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. */
+        enum { nomatches_len = 64 };
+        static struct { long codepoint[nomatches_len]; unsigned int idx; } nomatches;
+        static unsigned int ellipsis_width = 0;
+
+        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 = utf8strlen = 0;
+                utf8str = text;
+                nextfont = NULL;
+                while (*text) {
+                        utf8charlen = utf8decode(text, &utf8codepoint, UTF_SIZ);
+                        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;
+
+                        for (i = 0; i < nomatches_len; ++i) {
+                                /* avoid calling XftFontMatch if we know we won't find a match */
+                                if (utf8codepoint == nomatches.codepoint[i])
+                                        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.codepoint[++nomatches.idx % nomatches_len] = 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);
+}