1 files changed, 425 insertions, 0 deletions

diff --git a/src/drw/drw.c b/src/drw/drw.c
new file mode 100644
index 0000000..8f53beb
--- /dev/null
+++ b/src/drw/drw.c
@@ -0,0 +1,425 @@
+/* See LICENSE file for copyright and license details. */
+#include <X11/Xft/Xft.h>
+#include <X11/Xlib.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.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);
+}