st/x.c

/* See LICENSE for license details. */
#include <X11/XKBlib.h>
#include <X11/Xatom.h>
#include <X11/Xft/Xft.h>
#include <X11/Xlib.h>
#include <X11/cursorfont.h>
#include <X11/keysym.h>
#include <errno.h>
#include <libgen.h>
#include <limits.h>
#include <locale.h>
#include <math.h>
#include <signal.h>
#include <sys/select.h>
#include <time.h>
#include <unistd.h>

char *argv0;
#include "arg.h"
#include "hb.h"
#include "st.h"
#include "win.h"

/* types used in config.h */
typedef struct {
  uint mod;
  KeySym keysym;
  void (*func)(const Arg *);
  const Arg arg;
} Shortcut;

typedef struct {
  uint mod;
  uint button;
  void (*func)(const Arg *);
  const Arg arg;
  uint release;
  int altscrn; /* 0: don't care, -1: not alt screen, 1: alt screen */
} MouseShortcut;

typedef struct {
  KeySym k;
  uint mask;
  char *s;
  /* three-valued logic variables: 0 indifferent, 1 on, -1 off */
  signed char appkey;    /* application keypad */
  signed char appcursor; /* application cursor */
} Key;

/* X modifiers */
#define XK_ANY_MOD UINT_MAX
#define XK_NO_MOD 0
#define XK_SWITCH_MOD (1 << 13 | 1 << 14)

/* function definitions used in config.h */
static void clipcopy(const Arg *);
static void clippaste(const Arg *);
static void numlock(const Arg *);
static void selpaste(const Arg *);
static void swapcolors(const Arg *);
static void zoom(const Arg *);
static void zoomabs(const Arg *);
static void zoomreset(const Arg *);
static void ttysend(const Arg *);

/* config.h for applying patches and the configuration. */
#include "config.h"

/* XEMBED messages */
#define XEMBED_FOCUS_IN 4
#define XEMBED_FOCUS_OUT 5

/* macros */
#define IS_SET(flag) ((win.mode & (flag)) != 0)
#define TRUERED(x) (((x)&0xff0000) >> 8)
#define TRUEGREEN(x) (((x)&0xff00))
#define TRUEBLUE(x) (((x)&0xff) << 8)

typedef XftDraw *Draw;
typedef XftColor Color;
typedef XftGlyphFontSpec GlyphFontSpec;

/* Purely graphic info */
typedef struct {
  int tw, th; /* tty width and height */
  int w, h;   /* window width and height */
  int hborderpx, vborderpx;
  int ch;     /* char height */
  int cw;     /* char width  */
  int mode;   /* window state/mode flags */
  int cursor; /* cursor style */
} TermWindow;

typedef struct {
  Display *dpy;
  Colormap cmap;
  Window win;
  Drawable buf;
  GlyphFontSpec *specbuf; /* font spec buffer used for rendering */
  Atom xembed, wmdeletewin, netwmname, netwmiconname, netwmpid;
  struct {
    XIM xim;
    XIC xic;
    XPoint spot;
    XVaNestedList spotlist;
  } ime;
  Draw draw;
  Visual *vis;
  XSetWindowAttributes attrs;
  /* Here, we use the term *pointer* to differentiate the cursor
   * one sees when hovering the mouse over the terminal from, e.g.,
   * a green rectangle where text would be entered. */
  Cursor vpointer, bpointer; /* visible and hidden pointers */
  int pointerisvisible;
  int scr;
  int isfixed; /* is fixed geometry? */
  int depth;   /* bit depth */
  int l, t;    /* left and top offset */
  int gm;      /* geometry mask */
} XWindow;

typedef struct {
  Atom xtarget;
  char *primary, *clipboard;
  struct timespec tclick1;
  struct timespec tclick2;
} XSelection;

/* Font structure */
#define Font Font_
typedef struct {
  int height;
  int width;
  int ascent;
  int descent;
  int badslant;
  int badweight;
  short lbearing;
  short rbearing;
  XftFont *match;
  FcFontSet *set;
  FcPattern *pattern;
} Font;

/* Drawing Context */
typedef struct {
  Color *col;
  size_t collen;
  Font font, bfont, ifont, ibfont;
  GC gc;
} DC;

static inline ushort sixd_to_16bit(int);
static int xmakeglyphfontspecs(XftGlyphFontSpec *, const Glyph *, int, int,
                               int);
static void xdrawglyphfontspecs(const XftGlyphFontSpec *, Glyph, int, int, int);
static void xdrawglyph(Glyph, int, int);
static void xclear(int, int, int, int);
static int xgeommasktogravity(int);
static int ximopen(Display *);
static void ximinstantiate(Display *, XPointer, XPointer);
static void ximdestroy(XIM, XPointer, XPointer);
static int xicdestroy(XIC, XPointer, XPointer);
static void xinit(int, int);
static void cresize(int, int);
static void xresize(int, int);
static void xhints(void);
static int xloadcolor(int, const char *, Color *);
static int xloadfont(Font *, FcPattern *);
static void xloadfonts(const char *, double);
static int xloadsparefont(FcPattern *, int);
static void xloadsparefonts(void);
static void xunloadfont(Font *);
static void xunloadfonts(void);
static void xsetenv(void);
static void xseturgency(int);
static int evcol(XEvent *);
static int evrow(XEvent *);

static void expose(XEvent *);
static void visibility(XEvent *);
static void unmap(XEvent *);
static void kpress(XEvent *);
static void cmessage(XEvent *);
static void resize(XEvent *);
static void focus(XEvent *);
static uint buttonmask(uint);
static int mouseaction(XEvent *, uint);
static void brelease(XEvent *);
static void bpress(XEvent *);
static void bmotion(XEvent *);
static void propnotify(XEvent *);
static void selnotify(XEvent *);
static void selclear_(XEvent *);
static void selrequest(XEvent *);
static void setsel(char *, Time);
static void mousesel(XEvent *, int);
static void mousereport(XEvent *);
static char *kmap(KeySym, uint);
static int match(uint, uint);

static void run(void);
static void usage(void);

static void (*handler[LASTEvent])(XEvent *) = {
    [KeyPress] = kpress,
    [ClientMessage] = cmessage,
    [ConfigureNotify] = resize,
    [VisibilityNotify] = visibility,
    [UnmapNotify] = unmap,
    [Expose] = expose,
    [FocusIn] = focus,
    [FocusOut] = focus,
    [MotionNotify] = bmotion,
    [ButtonPress] = bpress,
    [ButtonRelease] = brelease,
    /*
     * Uncomment if you want the selection to disappear when you select
     * something different in another window.
     */
    /*	[SelectionClear] = selclear_, */
    [SelectionNotify] = selnotify,
    /*
     * PropertyNotify is only turned on when there is some INCR transfer
     * happening for the selection retrieval.
     */
    [PropertyNotify] = propnotify,
    [SelectionRequest] = selrequest,
};

/* Globals */
static DC dc;
static XWindow xw;
static XSelection xsel;
static TermWindow win;

/* Font Ring Cache */
enum { FRC_NORMAL, FRC_ITALIC, FRC_BOLD, FRC_ITALICBOLD };

typedef struct {
  XftFont *font;
  int flags;
  Rune unicodep;
} Fontcache;

/* Fontcache is an array now. A new font will be appended to the array. */
static Fontcache *frc = NULL;
static int frclen = 0;
static int frccap = 0;
static char *usedfont = NULL;
static double usedfontsize = 0;
static double defaultfontsize = 0;

static char *opt_alpha = NULL;
static char *opt_class = NULL;
static char **opt_cmd = NULL;
static char *opt_embed = NULL;
static char *opt_font = NULL;
static char *opt_io = NULL;
static char *opt_line = NULL;
static char *opt_name = NULL;
static char *opt_title = NULL;

static uint buttons; /* bit field of pressed buttons */

int usealtcolors = 0; /* 1 to use alternate palette */

void clipcopy(const Arg *dummy) {
  Atom clipboard;

  free(xsel.clipboard);
  xsel.clipboard = NULL;

  if (xsel.primary != NULL) {
    xsel.clipboard = xstrdup(xsel.primary);
    clipboard = XInternAtom(xw.dpy, "CLIPBOARD", 0);
    XSetSelectionOwner(xw.dpy, clipboard, xw.win, CurrentTime);
  }
}

void clippaste(const Arg *dummy) {
  Atom clipboard;

  clipboard = XInternAtom(xw.dpy, "CLIPBOARD", 0);
  XConvertSelection(xw.dpy, clipboard, xsel.xtarget, clipboard, xw.win,
                    CurrentTime);
}

void selpaste(const Arg *dummy) {
  XConvertSelection(xw.dpy, XA_PRIMARY, xsel.xtarget, XA_PRIMARY, xw.win,
                    CurrentTime);
}

void numlock(const Arg *dummy) { win.mode ^= MODE_NUMLOCK; }

void swapcolors(const Arg *dummy) {
  usealtcolors = !usealtcolors;
  xloadcols();
  redraw();
}

void zoom(const Arg *arg) {
  Arg larg;

  larg.f = usedfontsize + arg->f;
  zoomabs(&larg);
}

void zoomabs(const Arg *arg) {
  xunloadfonts();
  xloadfonts(usedfont, arg->f);
  xloadsparefonts();
  cresize(0, 0);
  redraw();
  xhints();
}

void zoomreset(const Arg *arg) {
  Arg larg;

  if (defaultfontsize > 0) {
    larg.f = defaultfontsize;
    zoomabs(&larg);
  }
}

void ttysend(const Arg *arg) { ttywrite(arg->s, strlen(arg->s), 1); }

int evcol(XEvent *e) {
  int x = e->xbutton.x - win.hborderpx;
  LIMIT(x, 0, win.tw - 1);
  return x / win.cw;
}

int evrow(XEvent *e) {
  int y = e->xbutton.y - win.vborderpx;
  LIMIT(y, 0, win.th - 1);
  return y / win.ch;
}

void mousesel(XEvent *e, int done) {
  int type, seltype = SEL_REGULAR;
  uint state = e->xbutton.state & ~(Button1Mask | forcemousemod);

  for (type = 1; type < LEN(selmasks); ++type) {
    if (match(selmasks[type], state)) {
      seltype = type;
      break;
    }
  }
  selextend(evcol(e), evrow(e), seltype, done);
  if (done)
    setsel(getsel(), e->xbutton.time);
}

void mousereport(XEvent *e) {
  int len, btn, code;
  int x = evcol(e), y = evrow(e);
  int state = e->xbutton.state;
  char buf[40];
  static int ox, oy;

  if (e->type == MotionNotify) {
    if (x == ox && y == oy)
      return;
    if (!IS_SET(MODE_MOUSEMOTION) && !IS_SET(MODE_MOUSEMANY))
      return;
    /* MODE_MOUSEMOTION: no reporting if no button is pressed */
    if (IS_SET(MODE_MOUSEMOTION) && buttons == 0)
      return;
    /* Set btn to lowest-numbered pressed button, or 12 if no
     * buttons are pressed. */
    for (btn = 1; btn <= 11 && !(buttons & (1 << (btn - 1))); btn++)
      ;
    code = 32;
  } else {
    btn = e->xbutton.button;
    /* Only buttons 1 through 11 can be encoded */
    if (btn < 1 || btn > 11)
      return;
    if (e->type == ButtonRelease) {
      /* MODE_MOUSEX10: no button release reporting */
      if (IS_SET(MODE_MOUSEX10))
        return;
      /* Don't send release events for the scroll wheel */
      if (btn == 4 || btn == 5)
        return;
    }
    code = 0;
  }

  ox = x;
  oy = y;

  /* Encode btn into code. If no button is pressed for a motion event in
   * MODE_MOUSEMANY, then encode it as a release. */
  if ((!IS_SET(MODE_MOUSESGR) && e->type == ButtonRelease) || btn == 12)
    code += 3;
  else if (btn >= 8)
    code += 128 + btn - 8;
  else if (btn >= 4)
    code += 64 + btn - 4;
  else
    code += btn - 1;

  if (!IS_SET(MODE_MOUSEX10)) {
    code += ((state & ShiftMask) ? 4 : 0) +
            ((state & Mod1Mask) ? 8 : 0) /* meta key: alt */
            + ((state & ControlMask) ? 16 : 0);
  }

  if (IS_SET(MODE_MOUSESGR)) {
    len = snprintf(buf, sizeof(buf), "\033[<%d;%d;%d%c", code, x + 1, y + 1,
                   e->type == ButtonRelease ? 'm' : 'M');
  } else if (x < 223 && y < 223) {
    len = snprintf(buf, sizeof(buf), "\033[M%c%c%c", 32 + code, 32 + x + 1,
                   32 + y + 1);
  } else {
    return;
  }

  ttywrite(buf, len, 0);
}

uint buttonmask(uint button) {
  return button == Button1   ? Button1Mask
         : button == Button2 ? Button2Mask
         : button == Button3 ? Button3Mask
         : button == Button4 ? Button4Mask
         : button == Button5 ? Button5Mask
                             : 0;
}

int mouseaction(XEvent *e, uint release) {
  MouseShortcut *ms;

  /* ignore Button<N>mask for Button<N> - it's set on release */
  uint state = e->xbutton.state & ~buttonmask(e->xbutton.button);

  for (ms = mshortcuts; ms < mshortcuts + LEN(mshortcuts); ms++) {
    if (ms->release == release && ms->button == e->xbutton.button &&
        (!ms->altscrn || (ms->altscrn == (tisaltscr() ? 1 : -1))) &&
        (match(ms->mod, state) || /* exact or forced */
         match(ms->mod, state & ~forcemousemod))) {
      ms->func(&(ms->arg));
      return 1;
    }
  }

  return 0;
}

void bpress(XEvent *e) {
  int btn = e->xbutton.button;
  struct timespec now;
  int snap;

  if (1 <= btn && btn <= 11)
    buttons |= 1 << (btn - 1);

  if (IS_SET(MODE_MOUSE) && !(e->xbutton.state & forcemousemod)) {
    mousereport(e);
    return;
  }

  if (mouseaction(e, 0))
    return;

  if (btn == Button1) {
    /*
     * If the user clicks below predefined timeouts specific
     * snapping behaviour is exposed.
     */
    clock_gettime(CLOCK_MONOTONIC, &now);
    if (TIMEDIFF(now, xsel.tclick2) <= tripleclicktimeout) {
      snap = SNAP_LINE;
    } else if (TIMEDIFF(now, xsel.tclick1) <= doubleclicktimeout) {
      snap = SNAP_WORD;
    } else {
      snap = 0;
    }
    xsel.tclick2 = xsel.tclick1;
    xsel.tclick1 = now;

    selstart(evcol(e), evrow(e), snap);
  }
}

void propnotify(XEvent *e) {
  XPropertyEvent *xpev;
  Atom clipboard = XInternAtom(xw.dpy, "CLIPBOARD", 0);

  xpev = &e->xproperty;
  if (xpev->state == PropertyNewValue &&
      (xpev->atom == XA_PRIMARY || xpev->atom == clipboard)) {
    selnotify(e);
  }
}

void selnotify(XEvent *e) {
  ulong nitems, ofs, rem;
  int format;
  uchar *data, *last, *repl;
  Atom type, incratom, property = None;

  incratom = XInternAtom(xw.dpy, "INCR", 0);

  ofs = 0;
  if (e->type == SelectionNotify)
    property = e->xselection.property;
  else if (e->type == PropertyNotify)
    property = e->xproperty.atom;

  if (property == None)
    return;

  do {
    if (XGetWindowProperty(xw.dpy, xw.win, property, ofs, BUFSIZ / 4, False,
                           AnyPropertyType, &type, &format, &nitems, &rem,
                           &data)) {
      fprintf(stderr, "Clipboard allocation failed\n");
      return;
    }

    if (e->type == PropertyNotify && nitems == 0 && rem == 0) {
      /*
       * If there is some PropertyNotify with no data, then
       * this is the signal of the selection owner that all
       * data has been transferred. We won't need to receive
       * PropertyNotify events anymore.
       */
      MODBIT(xw.attrs.event_mask, 0, PropertyChangeMask);
      XChangeWindowAttributes(xw.dpy, xw.win, CWEventMask, &xw.attrs);
    }

    if (type == incratom) {
      /*
       * Activate the PropertyNotify events so we receive
       * when the selection owner does send us the next
       * chunk of data.
       */
      MODBIT(xw.attrs.event_mask, 1, PropertyChangeMask);
      XChangeWindowAttributes(xw.dpy, xw.win, CWEventMask, &xw.attrs);

      /*
       * Deleting the property is the transfer start signal.
       */
      XDeleteProperty(xw.dpy, xw.win, (int)property);
      continue;
    }

    /*
     * As seen in getsel:
     * Line endings are inconsistent in the terminal and GUI world
     * copy and pasting. When receiving some selection data,
     * replace all '\n' with '\r'.
     * FIXME: Fix the computer world.
     */
    repl = data;
    last = data + nitems * format / 8;
    while ((repl = memchr(repl, '\n', last - repl))) {
      *repl++ = '\r';
    }

    if (IS_SET(MODE_BRCKTPASTE) && ofs == 0)
      ttywrite("\033[200~", 6, 0);
    ttywrite((char *)data, nitems * format / 8, 1);
    if (IS_SET(MODE_BRCKTPASTE) && rem == 0)
      ttywrite("\033[201~", 6, 0);
    XFree(data);
    /* number of 32-bit chunks returned */
    ofs += nitems * format / 32;
  } while (rem > 0);

  /*
   * Deleting the property again tells the selection owner to send the
   * next data chunk in the property.
   */
  XDeleteProperty(xw.dpy, xw.win, (int)property);
}

void xclipcopy(void) { clipcopy(NULL); }

void selclear_(XEvent *e) { selclear(); }

void selrequest(XEvent *e) {
  XSelectionRequestEvent *xsre;
  XSelectionEvent xev;
  Atom xa_targets, string, clipboard;
  char *seltext;

  xsre = (XSelectionRequestEvent *)e;
  xev.type = SelectionNotify;
  xev.requestor = xsre->requestor;
  xev.selection = xsre->selection;
  xev.target = xsre->target;
  xev.time = xsre->time;
  if (xsre->property == None)
    xsre->property = xsre->target;

  /* reject */
  xev.property = None;

  xa_targets = XInternAtom(xw.dpy, "TARGETS", 0);
  if (xsre->target == xa_targets) {
    /* respond with the supported type */
    string = xsel.xtarget;
    XChangeProperty(xsre->display, xsre->requestor, xsre->property, XA_ATOM, 32,
                    PropModeReplace, (uchar *)&string, 1);
    xev.property = xsre->property;
  } else if (xsre->target == xsel.xtarget || xsre->target == XA_STRING) {
    /*
     * xith XA_STRING non ascii characters may be incorrect in the
     * requestor. It is not our problem, use utf8.
     */
    clipboard = XInternAtom(xw.dpy, "CLIPBOARD", 0);
    if (xsre->selection == XA_PRIMARY) {
      seltext = xsel.primary;
    } else if (xsre->selection == clipboard) {
      seltext = xsel.clipboard;
    } else {
      fprintf(stderr, "Unhandled clipboard selection 0x%lx\n", xsre->selection);
      return;
    }
    if (seltext != NULL) {
      XChangeProperty(xsre->display, xsre->requestor, xsre->property,
                      xsre->target, 8, PropModeReplace, (uchar *)seltext,
                      strlen(seltext));
      xev.property = xsre->property;
    }
  }

  /* all done, send a notification to the listener */
  if (!XSendEvent(xsre->display, xsre->requestor, 1, 0, (XEvent *)&xev))
    fprintf(stderr, "Error sending SelectionNotify event\n");
}

void setsel(char *str, Time t) {
  if (!str)
    return;

  free(xsel.primary);
  xsel.primary = str;

  XSetSelectionOwner(xw.dpy, XA_PRIMARY, xw.win, t);
  if (XGetSelectionOwner(xw.dpy, XA_PRIMARY) != xw.win)
    selclear();
  clipcopy(NULL);
}

void xsetsel(char *str) { setsel(str, CurrentTime); }

void brelease(XEvent *e) {
  if (!xw.pointerisvisible) {
    XDefineCursor(xw.dpy, xw.win, xw.vpointer);
    xw.pointerisvisible = 1;
    if (!IS_SET(MODE_MOUSEMANY))
      xsetpointermotion(0);
  }
  int btn = e->xbutton.button;

  if (1 <= btn && btn <= 11)
    buttons &= ~(1 << (btn - 1));

  if (IS_SET(MODE_MOUSE) && !(e->xbutton.state & forcemousemod)) {
    mousereport(e);
    return;
  }

  if (mouseaction(e, 1))
    return;
  if (btn == Button1)
    mousesel(e, 1);
}

void bmotion(XEvent *e) {
  if (!xw.pointerisvisible) {
    XDefineCursor(xw.dpy, xw.win, xw.vpointer);
    xw.pointerisvisible = 1;
    if (!IS_SET(MODE_MOUSEMANY))
      xsetpointermotion(0);
  }

  if (IS_SET(MODE_MOUSE) && !(e->xbutton.state & forcemousemod)) {
    mousereport(e);
    return;
  }

  mousesel(e, 0);
}

void cresize(int width, int height) {
  int col, row;

  if (width != 0)
    win.w = width;
  if (height != 0)
    win.h = height;

  col = (win.w - 2 * borderpx) / win.cw;
  row = (win.h - 2 * borderpx) / win.ch;
  col = MAX(1, col);
  row = MAX(1, row);

  win.hborderpx = (win.w - col * win.cw) / 2;
  win.vborderpx = (win.h - row * win.ch) / 2;

  tresize(col, row);
  xresize(col, row);
  ttyresize(win.tw, win.th);
}

void xresize(int col, int row) {
  win.tw = col * win.cw;
  win.th = row * win.ch;

  XFreePixmap(xw.dpy, xw.buf);
  xw.buf = XCreatePixmap(xw.dpy, xw.win, win.w, win.h, xw.depth);
  XftDrawChange(xw.draw, xw.buf);
  xclear(0, 0, win.w, win.h);

  /* resize to new width */
  xw.specbuf = xrealloc(xw.specbuf, col * sizeof(GlyphFontSpec));
}

ushort sixd_to_16bit(int x) { return x == 0 ? 0 : 0x3737 + 0x2828 * x; }

const char *getcolorname(int i) {
  return (usealtcolors) ? altcolorname[i] : colorname[i];
}

int xloadcolor(int i, const char *name, Color *ncolor) {
  XRenderColor color = {.alpha = 0xffff};

  if (!name) {
    if (BETWEEN(i, 16, 255)) {  /* 256 color */
      if (i < 6 * 6 * 6 + 16) { /* same colors as xterm */
        color.red = sixd_to_16bit(((i - 16) / 36) % 6);
        color.green = sixd_to_16bit(((i - 16) / 6) % 6);
        color.blue = sixd_to_16bit(((i - 16) / 1) % 6);
      } else { /* greyscale */
        color.red = 0x0808 + 0x0a0a * (i - (6 * 6 * 6 + 16));
        color.green = color.blue = color.red;
      }
      return XftColorAllocValue(xw.dpy, xw.vis, xw.cmap, &color, ncolor);
    } else
      name = getcolorname(i);
  }

  return XftColorAllocName(xw.dpy, xw.vis, xw.cmap, name, ncolor);
}

void xloadcols(void) {
  int i;
  static int loaded;
  Color *cp;

  if (loaded) {
    for (cp = dc.col; cp < &dc.col[dc.collen]; ++cp)
      XftColorFree(xw.dpy, xw.vis, xw.cmap, cp);
  } else {
    dc.collen = MAX(LEN(colorname), 256);
    dc.col = xmalloc(dc.collen * sizeof(Color));
  }

  for (i = 0; i < dc.collen; i++)
    if (!xloadcolor(i, NULL, &dc.col[i])) {
      if (getcolorname(i))
        die("could not allocate color '%s'\n", getcolorname(i));
      else
        die("could not allocate color %d\n", i);
    }

  /* set alpha value of bg color */
  if (opt_alpha)
    alpha = strtof(opt_alpha, NULL);
  dc.col[defaultbg].color.alpha = (unsigned short)(0xffff * alpha);
  dc.col[defaultbg].pixel &= 0x00FFFFFF;
  dc.col[defaultbg].pixel |= (unsigned char)(0xff * alpha) << 24;
  loaded = 1;
}

int xgetcolor(int x, unsigned char *r, unsigned char *g, unsigned char *b) {
  if (!BETWEEN(x, 0, dc.collen))
    return 1;

  *r = dc.col[x].color.red >> 8;
  *g = dc.col[x].color.green >> 8;
  *b = dc.col[x].color.blue >> 8;

  return 0;
}

int xsetcolorname(int x, const char *name) {
  Color ncolor;

  if (!BETWEEN(x, 0, dc.collen))
    return 1;

  if (!xloadcolor(x, name, &ncolor))
    return 1;

  XftColorFree(xw.dpy, xw.vis, xw.cmap, &dc.col[x]);
  dc.col[x] = ncolor;

  return 0;
}

/*
 * Absolute coordinates.
 */
void xclear(int x1, int y1, int x2, int y2) {
  XftDrawRect(xw.draw, &dc.col[IS_SET(MODE_REVERSE) ? defaultfg : defaultbg],
              x1, y1, x2 - x1, y2 - y1);
}

void xhints(void) {
  XClassHint class = {opt_name ? opt_name : termname,
                      opt_class ? opt_class : termname};
  XWMHints wm = {.flags = InputHint, .input = 1};
  XSizeHints *sizeh;

  sizeh = XAllocSizeHints();

  sizeh->flags = PSize | PResizeInc | PBaseSize | PMinSize;
  sizeh->height = win.h;
  sizeh->width = win.w;
  sizeh->height_inc = 1;
  sizeh->width_inc = 1;
  sizeh->base_height = 2 * borderpx;
  sizeh->base_width = 2 * borderpx;
  sizeh->min_height = win.ch + 2 * borderpx;
  sizeh->min_width = win.cw + 2 * borderpx;
  if (xw.isfixed) {
    sizeh->flags |= PMaxSize;
    sizeh->min_width = sizeh->max_width = win.w;
    sizeh->min_height = sizeh->max_height = win.h;
  }
  if (xw.gm & (XValue | YValue)) {
    sizeh->flags |= USPosition | PWinGravity;
    sizeh->x = xw.l;
    sizeh->y = xw.t;
    sizeh->win_gravity = xgeommasktogravity(xw.gm);
  }

  XSetWMProperties(xw.dpy, xw.win, NULL, NULL, NULL, 0, sizeh, &wm, &class);
  XFree(sizeh);
}

int xgeommasktogravity(int mask) {
  switch (mask & (XNegative | YNegative)) {
  case 0:
    return NorthWestGravity;
  case XNegative:
    return NorthEastGravity;
  case YNegative:
    return SouthWestGravity;
  }

  return SouthEastGravity;
}

int xloadfont(Font *f, FcPattern *pattern) {
  FcPattern *configured;
  FcPattern *match;
  FcResult result;
  XGlyphInfo extents;
  int wantattr, haveattr;

  /*
   * Manually configure instead of calling XftMatchFont
   * so that we can use the configured pattern for
   * "missing glyph" lookups.
   */
  configured = FcPatternDuplicate(pattern);
  if (!configured)
    return 1;

  FcConfigSubstitute(NULL, configured, FcMatchPattern);
  XftDefaultSubstitute(xw.dpy, xw.scr, configured);

  match = FcFontMatch(NULL, configured, &result);
  if (!match) {
    FcPatternDestroy(configured);
    return 1;
  }

  if (!(f->match = XftFontOpenPattern(xw.dpy, match))) {
    FcPatternDestroy(configured);
    FcPatternDestroy(match);
    return 1;
  }

  if ((XftPatternGetInteger(pattern, "slant", 0, &wantattr) ==
       XftResultMatch)) {
    /*
     * Check if xft was unable to find a font with the appropriate
     * slant but gave us one anyway. Try to mitigate.
     */
    if ((XftPatternGetInteger(f->match->pattern, "slant", 0, &haveattr) !=
         XftResultMatch) ||
        haveattr < wantattr) {
      f->badslant = 1;
      fputs("font slant does not match\n", stderr);
    }
  }

  if ((XftPatternGetInteger(pattern, "weight", 0, &wantattr) ==
       XftResultMatch)) {
    if ((XftPatternGetInteger(f->match->pattern, "weight", 0, &haveattr) !=
         XftResultMatch) ||
        haveattr != wantattr) {
      f->badweight = 1;
      fputs("font weight does not match\n", stderr);
    }
  }

  XftTextExtentsUtf8(xw.dpy, f->match, (const FcChar8 *)ascii_printable,
                     strlen(ascii_printable), &extents);

  f->set = NULL;
  f->pattern = configured;

  f->ascent = f->match->ascent;
  f->descent = f->match->descent;
  f->lbearing = 0;
  f->rbearing = f->match->max_advance_width;

  f->height = f->ascent + f->descent;
  f->width = DIVCEIL(extents.xOff, strlen(ascii_printable));

  return 0;
}

void xloadfonts(const char *fontstr, double fontsize) {
  FcPattern *pattern;
  double fontval;

  if (fontstr[0] == '-')
    pattern = XftXlfdParse(fontstr, False, False);
  else
    pattern = FcNameParse((const FcChar8 *)fontstr);

  if (!pattern)
    die("can't open font %s\n", fontstr);

  if (fontsize > 1) {
    FcPatternDel(pattern, FC_PIXEL_SIZE);
    FcPatternDel(pattern, FC_SIZE);
    FcPatternAddDouble(pattern, FC_PIXEL_SIZE, (double)fontsize);
    usedfontsize = fontsize;
  } else {
    if (FcPatternGetDouble(pattern, FC_PIXEL_SIZE, 0, &fontval) ==
        FcResultMatch) {
      usedfontsize = fontval;
    } else if (FcPatternGetDouble(pattern, FC_SIZE, 0, &fontval) ==
               FcResultMatch) {
      usedfontsize = -1;
    } else {
      /*
       * Default font size is 12, if none given. This is to
       * have a known usedfontsize value.
       */
      FcPatternAddDouble(pattern, FC_PIXEL_SIZE, 12);
      usedfontsize = 12;
    }
    defaultfontsize = usedfontsize;
  }

  if (xloadfont(&dc.font, pattern))
    die("can't open font %s\n", fontstr);

  if (usedfontsize < 0) {
    FcPatternGetDouble(dc.font.match->pattern, FC_PIXEL_SIZE, 0, &fontval);
    usedfontsize = fontval;
    if (fontsize == 0)
      defaultfontsize = fontval;
  }

  /* Setting character width and height. */
  win.cw = ceilf(dc.font.width * cwscale);
  win.ch = ceilf(dc.font.height * chscale);

  FcPatternDel(pattern, FC_SLANT);
  FcPatternAddInteger(pattern, FC_SLANT, FC_SLANT_ITALIC);
  if (xloadfont(&dc.ifont, pattern))
    die("can't open font %s\n", fontstr);

  FcPatternDel(pattern, FC_WEIGHT);
  FcPatternAddInteger(pattern, FC_WEIGHT, FC_WEIGHT_BOLD);
  if (xloadfont(&dc.ibfont, pattern))
    die("can't open font %s\n", fontstr);

  FcPatternDel(pattern, FC_SLANT);
  FcPatternAddInteger(pattern, FC_SLANT, FC_SLANT_ROMAN);
  if (xloadfont(&dc.bfont, pattern))
    die("can't open font %s\n", fontstr);

  FcPatternDestroy(pattern);
}

int xloadsparefont(FcPattern *pattern, int flags) {
  FcPattern *match;
  FcResult result;

  match = FcFontMatch(NULL, pattern, &result);
  if (!match) {
    return 1;
  }

  if (!(frc[frclen].font = XftFontOpenPattern(xw.dpy, match))) {
    FcPatternDestroy(match);
    return 1;
  }

  frc[frclen].flags = flags;
  /* Believe U+0000 glyph will present in each default font */
  frc[frclen].unicodep = 0;
  frclen++;

  return 0;
}

void xloadsparefonts(void) {
  FcPattern *pattern;
  double sizeshift, fontval;
  int fc;
  char **fp;

  if (frclen != 0)
    die("can't embed spare fonts. cache isn't empty");

  /* Calculate count of spare fonts */
  fc = sizeof(font2) / sizeof(*font2);
  if (fc == 0)
    return;

  /* Allocate memory for cache entries. */
  if (frccap < 4 * fc) {
    frccap += 4 * fc - frccap;
    frc = xrealloc(frc, frccap * sizeof(Fontcache));
  }

  for (fp = font2; fp - font2 < fc; ++fp) {

    if (**fp == '-')
      pattern = XftXlfdParse(*fp, False, False);
    else
      pattern = FcNameParse((FcChar8 *)*fp);

    if (!pattern)
      die("can't open spare font %s\n", *fp);

    if (defaultfontsize > 0) {
      sizeshift = usedfontsize - defaultfontsize;
      if (sizeshift != 0 && FcPatternGetDouble(pattern, FC_PIXEL_SIZE, 0,
                                               &fontval) == FcResultMatch) {
        fontval += sizeshift;
        FcPatternDel(pattern, FC_PIXEL_SIZE);
        FcPatternDel(pattern, FC_SIZE);
        FcPatternAddDouble(pattern, FC_PIXEL_SIZE, fontval);
      }
    }

    FcPatternAddBool(pattern, FC_SCALABLE, 1);

    FcConfigSubstitute(NULL, pattern, FcMatchPattern);
    XftDefaultSubstitute(xw.dpy, xw.scr, pattern);

    if (xloadsparefont(pattern, FRC_NORMAL))
      die("can't open spare font %s\n", *fp);

    FcPatternDel(pattern, FC_SLANT);
    FcPatternAddInteger(pattern, FC_SLANT, FC_SLANT_ITALIC);
    if (xloadsparefont(pattern, FRC_ITALIC))
      die("can't open spare font %s\n", *fp);

    FcPatternDel(pattern, FC_WEIGHT);
    FcPatternAddInteger(pattern, FC_WEIGHT, FC_WEIGHT_BOLD);
    if (xloadsparefont(pattern, FRC_ITALICBOLD))
      die("can't open spare font %s\n", *fp);

    FcPatternDel(pattern, FC_SLANT);
    FcPatternAddInteger(pattern, FC_SLANT, FC_SLANT_ROMAN);
    if (xloadsparefont(pattern, FRC_BOLD))
      die("can't open spare font %s\n", *fp);

    FcPatternDestroy(pattern);
  }
}

void xunloadfont(Font *f) {
  XftFontClose(xw.dpy, f->match);
  FcPatternDestroy(f->pattern);
  if (f->set)
    FcFontSetDestroy(f->set);
}

void xunloadfonts(void) {
  /* Clear Harfbuzz font cache. */
  hbunloadfonts();

  /* Free the loaded fonts in the font cache.  */
  while (frclen > 0)
    XftFontClose(xw.dpy, frc[--frclen].font);

  xunloadfont(&dc.font);
  xunloadfont(&dc.bfont);
  xunloadfont(&dc.ifont);
  xunloadfont(&dc.ibfont);
}

int ximopen(Display *dpy) {
  XIMCallback imdestroy = {.client_data = NULL, .callback = ximdestroy};
  XICCallback icdestroy = {.client_data = NULL, .callback = xicdestroy};

  xw.ime.xim = XOpenIM(xw.dpy, NULL, NULL, NULL);
  if (xw.ime.xim == NULL)
    return 0;

  if (XSetIMValues(xw.ime.xim, XNDestroyCallback, &imdestroy, NULL))
    fprintf(stderr, "XSetIMValues: "
                    "Could not set XNDestroyCallback.\n");

  xw.ime.spotlist = XVaCreateNestedList(0, XNSpotLocation, &xw.ime.spot, NULL);

  if (xw.ime.xic == NULL) {
    xw.ime.xic = XCreateIC(xw.ime.xim, XNInputStyle,
                           XIMPreeditNothing | XIMStatusNothing, XNClientWindow,
                           xw.win, XNDestroyCallback, &icdestroy, NULL);
  }
  if (xw.ime.xic == NULL)
    fprintf(stderr, "XCreateIC: Could not create input context.\n");

  return 1;
}

void ximinstantiate(Display *dpy, XPointer client, XPointer call) {
  if (ximopen(dpy))
    XUnregisterIMInstantiateCallback(xw.dpy, NULL, NULL, NULL, ximinstantiate,
                                     NULL);
}

void ximdestroy(XIM xim, XPointer client, XPointer call) {
  xw.ime.xim = NULL;
  XRegisterIMInstantiateCallback(xw.dpy, NULL, NULL, NULL, ximinstantiate,
                                 NULL);
  XFree(xw.ime.spotlist);
}

int xicdestroy(XIC xim, XPointer client, XPointer call) {
  xw.ime.xic = NULL;
  return 1;
}

void xinit(int cols, int rows) {
  XGCValues gcvalues;
  Window parent;
  pid_t thispid = getpid();
  XColor xmousefg, xmousebg;
  Pixmap blankpm;
  XWindowAttributes attr;
  XVisualInfo vis;

  if (!(xw.dpy = XOpenDisplay(NULL)))
    die("can't open display\n");
  xw.scr = XDefaultScreen(xw.dpy);

  if (!(opt_embed && (parent = strtol(opt_embed, NULL, 0)))) {
    parent = XRootWindow(xw.dpy, xw.scr);
    xw.depth = 32;
  } else {
    XGetWindowAttributes(xw.dpy, parent, &attr);
    xw.depth = attr.depth;
  }

  XMatchVisualInfo(xw.dpy, xw.scr, xw.depth, TrueColor, &vis);
  xw.vis = vis.visual;

  /* font */
  if (!FcInit())
    die("could not init fontconfig.\n");

  usedfont = (opt_font == NULL) ? font : opt_font;
  xloadfonts(usedfont, 0);

  /* spare fonts */
  xloadsparefonts();

  /* colors */
  xw.cmap = XCreateColormap(xw.dpy, parent, xw.vis, None);
  xloadcols();

  /* adjust fixed window geometry */
  win.w = 2 * win.hborderpx + cols * win.cw;
  win.h = 2 * win.vborderpx + rows * win.ch;
  if (xw.gm & XNegative)
    xw.l += DisplayWidth(xw.dpy, xw.scr) - win.w - 2;
  if (xw.gm & YNegative)
    xw.t += DisplayHeight(xw.dpy, xw.scr) - win.h - 2;

  /* Events */
  xw.attrs.background_pixel = dc.col[defaultbg].pixel;
  xw.attrs.border_pixel = dc.col[defaultbg].pixel;
  xw.attrs.bit_gravity = NorthWestGravity;
  xw.attrs.event_mask = FocusChangeMask | KeyPressMask | KeyReleaseMask |
                        ExposureMask | VisibilityChangeMask |
                        StructureNotifyMask | ButtonMotionMask |
                        ButtonPressMask | ButtonReleaseMask;
  xw.attrs.colormap = xw.cmap;

  xw.win = XCreateWindow(xw.dpy, parent, xw.l, xw.t, win.w, win.h, 0, xw.depth,
                         InputOutput, xw.vis,
                         CWBackPixel | CWBorderPixel | CWBitGravity |
                             CWEventMask | CWColormap,
                         &xw.attrs);

  memset(&gcvalues, 0, sizeof(gcvalues));
  gcvalues.graphics_exposures = False;
  xw.buf = XCreatePixmap(xw.dpy, xw.win, win.w, win.h, xw.depth);
  dc.gc = XCreateGC(xw.dpy, xw.buf, GCGraphicsExposures, &gcvalues);
  XSetForeground(xw.dpy, dc.gc, dc.col[defaultbg].pixel);
  XFillRectangle(xw.dpy, xw.buf, dc.gc, 0, 0, win.w, win.h);

  /* font spec buffer */
  xw.specbuf = xmalloc(cols * sizeof(GlyphFontSpec));

  /* Xft rendering context */
  xw.draw = XftDrawCreate(xw.dpy, xw.buf, xw.vis, xw.cmap);

  /* input methods */
  if (!ximopen(xw.dpy)) {
    XRegisterIMInstantiateCallback(xw.dpy, NULL, NULL, NULL, ximinstantiate,
                                   NULL);
  }

  /* white cursor, black outline */
  xw.pointerisvisible = 1;
  xw.vpointer = XCreateFontCursor(xw.dpy, mouseshape);
  XDefineCursor(xw.dpy, xw.win, xw.vpointer);

  if (XParseColor(xw.dpy, xw.cmap, getcolorname(mousefg), &xmousefg) == 0) {
    xmousefg.red = 0xffff;
    xmousefg.green = 0xffff;
    xmousefg.blue = 0xffff;
  }

  if (XParseColor(xw.dpy, xw.cmap, getcolorname(mousebg), &xmousebg) == 0) {
    xmousebg.red = 0x0000;
    xmousebg.green = 0x0000;
    xmousebg.blue = 0x0000;
  }

  XRecolorCursor(xw.dpy, xw.vpointer, &xmousefg, &xmousebg);
  blankpm = XCreateBitmapFromData(xw.dpy, xw.win, &(char){0}, 1, 1);
  xw.bpointer =
      XCreatePixmapCursor(xw.dpy, blankpm, blankpm, &xmousefg, &xmousebg, 0, 0);

  xw.xembed = XInternAtom(xw.dpy, "_XEMBED", False);
  xw.wmdeletewin = XInternAtom(xw.dpy, "WM_DELETE_WINDOW", False);
  xw.netwmname = XInternAtom(xw.dpy, "_NET_WM_NAME", False);
  xw.netwmiconname = XInternAtom(xw.dpy, "_NET_WM_ICON_NAME", False);
  XSetWMProtocols(xw.dpy, xw.win, &xw.wmdeletewin, 1);

  xw.netwmpid = XInternAtom(xw.dpy, "_NET_WM_PID", False);
  XChangeProperty(xw.dpy, xw.win, xw.netwmpid, XA_CARDINAL, 32, PropModeReplace,
                  (uchar *)&thispid, 1);

  win.mode = MODE_NUMLOCK;
  resettitle();
  xhints();
  XMapWindow(xw.dpy, xw.win);
  XSync(xw.dpy, False);

  clock_gettime(CLOCK_MONOTONIC, &xsel.tclick1);
  clock_gettime(CLOCK_MONOTONIC, &xsel.tclick2);
  xsel.primary = NULL;
  xsel.clipboard = NULL;
  xsel.xtarget = XInternAtom(xw.dpy, "UTF8_STRING", 0);
  if (xsel.xtarget == None)
    xsel.xtarget = XA_STRING;

  boxdraw_xinit(xw.dpy, xw.cmap, xw.draw, xw.vis);
}

int xmakeglyphfontspecs(XftGlyphFontSpec *specs, const Glyph *glyphs, int len,
                        int x, int y) {
  float winx = win.hborderpx + x * win.cw, winy = win.vborderpx + y * win.ch,
        xp, yp;
  ushort mode, prevmode = USHRT_MAX;
  Font *font = &dc.font;
  int frcflags = FRC_NORMAL;
  float runewidth = win.cw;
  Rune rune;
  FT_UInt glyphidx;
  FcResult fcres;
  FcPattern *fcpattern, *fontpattern;
  FcFontSet *fcsets[] = {NULL};
  FcCharSet *fccharset;
  int i, f, numspecs = 0;

  for (i = 0, xp = winx, yp = winy + font->ascent; i < len; ++i) {
    /* Fetch rune and mode for current glyph. */
    rune = glyphs[i].u;
    mode = glyphs[i].mode;

    /* Skip dummy wide-character spacing. */
    if (mode & ATTR_WDUMMY)
      continue;

    /* Determine font for glyph if different from previous glyph. */
    if (prevmode != mode) {
      prevmode = mode;
      font = &dc.font;
      frcflags = FRC_NORMAL;
      runewidth = win.cw * ((mode & ATTR_WIDE) ? 2.0f : 1.0f);
      if ((mode & ATTR_ITALIC) && (mode & ATTR_BOLD)) {
        font = &dc.ibfont;
        frcflags = FRC_ITALICBOLD;
      } else if (mode & ATTR_ITALIC) {
        font = &dc.ifont;
        frcflags = FRC_ITALIC;
      } else if (mode & ATTR_BOLD) {
        font = &dc.bfont;
        frcflags = FRC_BOLD;
      }
      yp = winy + font->ascent;
    }

    if (mode & ATTR_BOXDRAW) {
      /* minor shoehorning: boxdraw uses only this ushort */
      glyphidx = boxdrawindex(&glyphs[i]);
    } else {
      /* Lookup character index with default font. */
      glyphidx = XftCharIndex(xw.dpy, font->match, rune);
    }
    if (glyphidx) {
      specs[numspecs].font = font->match;
      specs[numspecs].glyph = glyphidx;
      specs[numspecs].x = (short)xp;
      specs[numspecs].y = (short)yp;
      xp += runewidth;
      numspecs++;
      continue;
    }

    /* Fallback on font cache, search the font cache for match. */
    for (f = 0; f < frclen; f++) {
      glyphidx = XftCharIndex(xw.dpy, frc[f].font, rune);
      /* Everything correct. */
      if (glyphidx && frc[f].flags == frcflags)
        break;
      /* We got a default font for a not found glyph. */
      if (!glyphidx && frc[f].flags == frcflags && frc[f].unicodep == rune) {
        break;
      }
    }

    /* Nothing was found. Use fontconfig to find matching font. */
    if (f >= frclen) {
      if (!font->set)
        font->set = FcFontSort(0, font->pattern, 1, 0, &fcres);
      fcsets[0] = font->set;

      /*
       * Nothing was found in the cache. Now use
       * some dozen of Fontconfig calls to get the
       * font for one single character.
       *
       * Xft and fontconfig are design failures.
       */
      fcpattern = FcPatternDuplicate(font->pattern);
      fccharset = FcCharSetCreate();

      FcCharSetAddChar(fccharset, rune);
      FcPatternAddCharSet(fcpattern, FC_CHARSET, fccharset);
      FcPatternAddBool(fcpattern, FC_SCALABLE, 1);

      FcConfigSubstitute(0, fcpattern, FcMatchPattern);
      FcDefaultSubstitute(fcpattern);

      fontpattern = FcFontSetMatch(0, fcsets, 1, fcpattern, &fcres);

      /* Allocate memory for the new cache entry. */
      if (frclen >= frccap) {
        frccap += 16;
        frc = xrealloc(frc, frccap * sizeof(Fontcache));
      }

      frc[frclen].font = XftFontOpenPattern(xw.dpy, fontpattern);
      if (!frc[frclen].font)
        die("XftFontOpenPattern failed seeking fallback font: %s\n",
            strerror(errno));
      frc[frclen].flags = frcflags;
      frc[frclen].unicodep = rune;

      glyphidx = XftCharIndex(xw.dpy, frc[frclen].font, rune);

      f = frclen;
      frclen++;

      FcPatternDestroy(fcpattern);
      FcCharSetDestroy(fccharset);
    }

    specs[numspecs].font = frc[f].font;
    specs[numspecs].glyph = glyphidx;
    specs[numspecs].x = (short)xp;
    specs[numspecs].y = (short)yp;
    xp += runewidth;
    numspecs++;
  }

  /* Harfbuzz transformation for ligatures. */
  hbtransform(specs, glyphs, len, x, y);

  return numspecs;
}

void xdrawglyphfontspecs(const XftGlyphFontSpec *specs, Glyph base, int len,
                         int x, int y) {
  int charlen = len * ((base.mode & ATTR_WIDE) ? 2 : 1);
  int winx = win.hborderpx + x * win.cw, winy = win.vborderpx + y * win.ch,
      width = charlen * win.cw;
  Color *fg, *bg, *temp, revfg, revbg, truefg, truebg;
  XRenderColor colfg, colbg;
  XRectangle r;

  /* Fallback on color display for attributes not supported by the font */
  if (base.mode & ATTR_ITALIC && base.mode & ATTR_BOLD) {
    if (dc.ibfont.badslant || dc.ibfont.badweight)
      base.fg = defaultattr;
  } else if ((base.mode & ATTR_ITALIC && dc.ifont.badslant) ||
             (base.mode & ATTR_BOLD && dc.bfont.badweight)) {
    base.fg = defaultattr;
  }

  if (IS_TRUECOL(base.fg)) {
    colfg.alpha = 0xffff;
    colfg.red = TRUERED(base.fg);
    colfg.green = TRUEGREEN(base.fg);
    colfg.blue = TRUEBLUE(base.fg);
    XftColorAllocValue(xw.dpy, xw.vis, xw.cmap, &colfg, &truefg);
    fg = &truefg;
  } else {
    fg = &dc.col[base.fg];
  }

  if (IS_TRUECOL(base.bg)) {
    colbg.alpha = 0xffff;
    colbg.green = TRUEGREEN(base.bg);
    colbg.red = TRUERED(base.bg);
    colbg.blue = TRUEBLUE(base.bg);
    XftColorAllocValue(xw.dpy, xw.vis, xw.cmap, &colbg, &truebg);
    bg = &truebg;
  } else {
    bg = &dc.col[base.bg];
  }

  /* Change basic system colors [0-7] to bright system colors [8-15] */
  if ((base.mode & ATTR_BOLD_FAINT) == ATTR_BOLD && BETWEEN(base.fg, 0, 7))
    fg = &dc.col[base.fg];

  if (IS_SET(MODE_REVERSE)) {
    if (fg == &dc.col[defaultfg]) {
      fg = &dc.col[defaultbg];
    } else {
      colfg.red = ~fg->color.red;
      colfg.green = ~fg->color.green;
      colfg.blue = ~fg->color.blue;
      colfg.alpha = fg->color.alpha;
      XftColorAllocValue(xw.dpy, xw.vis, xw.cmap, &colfg, &revfg);
      fg = &revfg;
    }

    if (bg == &dc.col[defaultbg]) {
      bg = &dc.col[defaultfg];
    } else {
      colbg.red = ~bg->color.red;
      colbg.green = ~bg->color.green;
      colbg.blue = ~bg->color.blue;
      colbg.alpha = bg->color.alpha;
      XftColorAllocValue(xw.dpy, xw.vis, xw.cmap, &colbg, &revbg);
      bg = &revbg;
    }
  }

  if ((base.mode & ATTR_BOLD_FAINT) == ATTR_FAINT) {
    colfg.red = fg->color.red / 2;
    colfg.green = fg->color.green / 2;
    colfg.blue = fg->color.blue / 2;
    colfg.alpha = fg->color.alpha;
    XftColorAllocValue(xw.dpy, xw.vis, xw.cmap, &colfg, &revfg);
    fg = &revfg;
  }

  if (base.mode & ATTR_REVERSE) {
    temp = fg;
    fg = bg;
    bg = temp;
  }

  if (base.mode & ATTR_BLINK && win.mode & MODE_BLINK)
    fg = bg;

  if (base.mode & ATTR_INVISIBLE)
    fg = bg;

  /* Intelligent cleaning up of the borders. */
  if (x == 0) {
    xclear(0, (y == 0) ? 0 : winy, win.vborderpx,
           winy + win.ch +
               ((winy + win.ch >= win.vborderpx + win.th) ? win.h : 0));
  }
  if (winx + width >= win.hborderpx + win.tw) {
    xclear(
        winx + width, (y == 0) ? 0 : winy, win.w,
        ((winy + win.ch >= win.vborderpx + win.th) ? win.h : (winy + win.ch)));
  }
  if (y == 0)
    xclear(winx, 0, winx + width, win.hborderpx);
  if (winy + win.ch >= win.vborderpx + win.th)
    xclear(winx, winy + win.ch, winx + width, win.h);

  /* Clean up the region we want to draw to. */
  XftDrawRect(xw.draw, bg, winx, winy, width, win.ch);

  /* Set the clip region because Xft is sometimes dirty. */
  r.x = 0;
  r.y = 0;
  r.height = win.ch;
  r.width = width;
  XftDrawSetClipRectangles(xw.draw, winx, winy, &r, 1);

  if (base.mode & ATTR_BOXDRAW) {
    drawboxes(winx, winy, width / len, win.ch, fg, bg, specs, len);
  } else {
    /* Render the glyphs. */
    XftDrawGlyphFontSpec(xw.draw, fg, specs, len);
  }

  /* Render underline and strikethrough. */
  if (base.mode & ATTR_UNDERLINE) {
    XftDrawRect(xw.draw, fg, winx, winy + dc.font.ascent + 1, width, 1);
  }

  if (base.mode & ATTR_STRUCK) {
    XftDrawRect(xw.draw, fg, winx, winy + 2 * dc.font.ascent / 3, width, 1);
  }

  /* Reset clip to none. */
  XftDrawSetClip(xw.draw, 0);
}

void xdrawglyph(Glyph g, int x, int y) {
  int numspecs;
  XftGlyphFontSpec spec;

  numspecs = xmakeglyphfontspecs(&spec, &g, 1, x, y);
  xdrawglyphfontspecs(&spec, g, numspecs, x, y);
}

void xdrawcursor(int cx, int cy, Glyph g, int ox, int oy, Glyph og, Line line,
                 int len) {
  Color drawcol;

  /* remove the old cursor */
  if (selected(ox, oy))
    og.mode ^= ATTR_REVERSE;

  /* Redraw the line where cursor was previously.
   * It will restore the ligatures broken by the cursor. */
  xdrawline(line, 0, oy, len);

  if (IS_SET(MODE_HIDE))
    return;

  /*
   * Select the right color for the right mode.
   */
  g.mode &= ATTR_BOLD | ATTR_ITALIC | ATTR_UNDERLINE | ATTR_STRUCK | ATTR_WIDE |
            ATTR_BOXDRAW;

  if (IS_SET(MODE_REVERSE)) {
    g.mode |= ATTR_REVERSE;
    g.bg = defaultfg;
    if (selected(cx, cy)) {
      drawcol = dc.col[defaultcs];
      g.fg = defaultrcs;
    } else {
      drawcol = dc.col[defaultrcs];
      g.fg = defaultcs;
    }
  } else {
    if (selected(cx, cy)) {
      g.fg = defaultfg;
      g.bg = defaultrcs;
    } else {
      g.fg = defaultbg;
      g.bg = defaultcs;
    }
    drawcol = dc.col[g.bg];
  }

  /* draw the new one */
  if (IS_SET(MODE_FOCUSED)) {
    switch (win.cursor) {
    case 7:         /* st extension */
      g.u = 0x2603; /* snowman (U+2603) */
                    /* FALLTHROUGH */
    case 0:         /* Blinking Block */
    case 1:         /* Blinking Block (Default) */
    case 2:         /* Steady Block */
      xdrawglyph(g, cx, cy);
      break;
    case 3: /* Blinking Underline */
    case 4: /* Steady Underline */
      XftDrawRect(xw.draw, &drawcol, win.hborderpx + cx * win.cw,
                  win.vborderpx + (cy + 1) * win.ch - cursorthickness, win.cw,
                  cursorthickness);
      break;
    case 5: /* Blinking bar */
    case 6: /* Steady bar */
      XftDrawRect(xw.draw, &drawcol, win.hborderpx + cx * win.cw,
                  win.vborderpx + cy * win.ch, cursorthickness, win.ch);
      break;
    }
  } else {
    XftDrawRect(xw.draw, &drawcol, win.hborderpx + cx * win.cw,
                win.vborderpx + cy * win.ch, win.cw - 1, 1);
    XftDrawRect(xw.draw, &drawcol, win.hborderpx + cx * win.cw,
                win.vborderpx + cy * win.ch, 1, win.ch - 1);
    XftDrawRect(xw.draw, &drawcol, win.hborderpx + (cx + 1) * win.cw - 1,
                win.vborderpx + cy * win.ch, 1, win.ch - 1);
    XftDrawRect(xw.draw, &drawcol, win.hborderpx + cx * win.cw,
                win.vborderpx + (cy + 1) * win.ch - 1, win.cw, 1);
  }
}

void xsetenv(void) {
  char buf[sizeof(long) * 8 + 1];

  snprintf(buf, sizeof(buf), "%lu", xw.win);
  setenv("WINDOWID", buf, 1);
}

void xseticontitle(char *p) {
  XTextProperty prop;
  DEFAULT(p, opt_title);

  if (Xutf8TextListToTextProperty(xw.dpy, &p, 1, XUTF8StringStyle, &prop) !=
      Success)
    return;
  XSetWMIconName(xw.dpy, xw.win, &prop);
  XSetTextProperty(xw.dpy, xw.win, &prop, xw.netwmiconname);
  XFree(prop.value);
}

void xsettitle(char *p) {
  XTextProperty prop;
  DEFAULT(p, opt_title);

  if (Xutf8TextListToTextProperty(xw.dpy, &p, 1, XUTF8StringStyle, &prop) !=
      Success)
    return;
  XSetWMName(xw.dpy, xw.win, &prop);
  XSetTextProperty(xw.dpy, xw.win, &prop, xw.netwmname);
  XFree(prop.value);
}

int xstartdraw(void) { return IS_SET(MODE_VISIBLE); }

void xdrawline(Line line, int x1, int y1, int x2) {
  int i, x, ox, numspecs;
  Glyph base, new;
  XftGlyphFontSpec *specs = xw.specbuf;

  numspecs = xmakeglyphfontspecs(specs, &line[x1], x2 - x1, x1, y1);
  i = ox = 0;
  for (x = x1; x < x2 && i < numspecs; x++) {
    new = line[x];
    if (new.mode == ATTR_WDUMMY)
      continue;
    if (selected(x, y1))
      new.mode ^= ATTR_REVERSE;
    if (i > 0 && ATTRCMP(base, new)) {
      xdrawglyphfontspecs(specs, base, i, ox, y1);
      specs += i;
      numspecs -= i;
      i = 0;
    }
    if (i == 0) {
      ox = x;
      base = new;
    }
    i++;
  }
  if (i > 0)
    xdrawglyphfontspecs(specs, base, i, ox, y1);
}

void xfinishdraw(void) {
  XCopyArea(xw.dpy, xw.buf, xw.win, dc.gc, 0, 0, win.w, win.h, 0, 0);
  XSetForeground(xw.dpy, dc.gc,
                 dc.col[IS_SET(MODE_REVERSE) ? defaultfg : defaultbg].pixel);
}

void xximspot(int x, int y) {
  if (xw.ime.xic == NULL)
    return;

  xw.ime.spot.x = borderpx + x * win.cw;
  xw.ime.spot.y = borderpx + (y + 1) * win.ch;

  XSetICValues(xw.ime.xic, XNPreeditAttributes, xw.ime.spotlist, NULL);
}

void expose(XEvent *ev) { redraw(); }

void visibility(XEvent *ev) {
  XVisibilityEvent *e = &ev->xvisibility;

  MODBIT(win.mode, e->state != VisibilityFullyObscured, MODE_VISIBLE);
}

void unmap(XEvent *ev) { win.mode &= ~MODE_VISIBLE; }

void xsetpointermotion(int set) {
  if (!set && !xw.pointerisvisible)
    return;
  MODBIT(xw.attrs.event_mask, set, PointerMotionMask);
  XChangeWindowAttributes(xw.dpy, xw.win, CWEventMask, &xw.attrs);
}

void xsetmode(int set, unsigned int flags) {
  int mode = win.mode;
  MODBIT(win.mode, set, flags);
  if ((win.mode & MODE_REVERSE) != (mode & MODE_REVERSE))
    redraw();
}

int xsetcursor(int cursor) {
  if (!BETWEEN(cursor, 0, 7)) /* 7: st extension */
    return 1;
  win.cursor = cursor;
  return 0;
}

void xseturgency(int add) {
  XWMHints *h = XGetWMHints(xw.dpy, xw.win);

  MODBIT(h->flags, add, XUrgencyHint);
  XSetWMHints(xw.dpy, xw.win, h);
  XFree(h);
}

void xbell(void) {
  if (!(IS_SET(MODE_FOCUSED)))
    xseturgency(1);
  if (bellvolume)
    XkbBell(xw.dpy, xw.win, bellvolume, (Atom)NULL);
}

void focus(XEvent *ev) {
  XFocusChangeEvent *e = &ev->xfocus;

  if (e->mode == NotifyGrab)
    return;

  if (ev->type == FocusIn) {
    if (xw.ime.xic)
      XSetICFocus(xw.ime.xic);
    win.mode |= MODE_FOCUSED;
    xseturgency(0);
    if (IS_SET(MODE_FOCUS))
      ttywrite("\033[I", 3, 0);
  } else {
    if (xw.ime.xic)
      XUnsetICFocus(xw.ime.xic);
    win.mode &= ~MODE_FOCUSED;
    if (IS_SET(MODE_FOCUS))
      ttywrite("\033[O", 3, 0);
  }
}

int match(uint mask, uint state) {
  return mask == XK_ANY_MOD || mask == (state & ~ignoremod);
}

char *kmap(KeySym k, uint state) {
  Key *kp;
  int i;

  /* Check for mapped keys out of X11 function keys. */
  for (i = 0; i < LEN(mappedkeys); i++) {
    if (mappedkeys[i] == k)
      break;
  }
  if (i == LEN(mappedkeys)) {
    if ((k & 0xFFFF) < 0xFD00)
      return NULL;
  }

  for (kp = key; kp < key + LEN(key); kp++) {
    if (kp->k != k)
      continue;

    if (!match(kp->mask, state))
      continue;

    if (IS_SET(MODE_APPKEYPAD) ? kp->appkey < 0 : kp->appkey > 0)
      continue;
    if (IS_SET(MODE_NUMLOCK) && kp->appkey == 2)
      continue;

    if (IS_SET(MODE_APPCURSOR) ? kp->appcursor < 0 : kp->appcursor > 0)
      continue;

    return kp->s;
  }

  return NULL;
}

void kpress(XEvent *ev) {
  XKeyEvent *e = &ev->xkey;
  KeySym ksym;
  char buf[64], *customkey;
  int len;
  Rune c;
  Status status;
  Shortcut *bp;

  if (xw.pointerisvisible) {
    XDefineCursor(xw.dpy, xw.win, xw.bpointer);
    xsetpointermotion(1);
    xw.pointerisvisible = 0;
  }

  if (IS_SET(MODE_KBDLOCK))
    return;

  if (xw.ime.xic)
    len = XmbLookupString(xw.ime.xic, e, buf, sizeof buf, &ksym, &status);
  else
    len = XLookupString(e, buf, sizeof buf, &ksym, NULL);
  /* 1. shortcuts */
  for (bp = shortcuts; bp < shortcuts + LEN(shortcuts); bp++) {
    if (ksym == bp->keysym && match(bp->mod, e->state)) {
      bp->func(&(bp->arg));
      return;
    }
  }

  /* 2. custom keys from config.h */
  if ((customkey = kmap(ksym, e->state))) {
    ttywrite(customkey, strlen(customkey), 1);
    return;
  }

  /* 3. composed string from input method */
  if (len == 0)
    return;
  if (len == 1 && e->state & Mod1Mask) {
    if (IS_SET(MODE_8BIT)) {
      if (*buf < 0177) {
        c = *buf | 0x80;
        len = utf8encode(c, buf);
      }
    } else {
      buf[1] = buf[0];
      buf[0] = '\033';
      len = 2;
    }
  }
  ttywrite(buf, len, 1);
}

void cmessage(XEvent *e) {
  /*
   * See xembed specs
   *  http://standards.freedesktop.org/xembed-spec/xembed-spec-latest.html
   */
  if (e->xclient.message_type == xw.xembed && e->xclient.format == 32) {
    if (e->xclient.data.l[1] == XEMBED_FOCUS_IN) {
      win.mode |= MODE_FOCUSED;
      xseturgency(0);
    } else if (e->xclient.data.l[1] == XEMBED_FOCUS_OUT) {
      win.mode &= ~MODE_FOCUSED;
    }
  } else if (e->xclient.data.l[0] == xw.wmdeletewin) {
    ttyhangup();
    exit(0);
  }
}

void resize(XEvent *e) {
  if (e->xconfigure.width == win.w && e->xconfigure.height == win.h)
    return;

  cresize(e->xconfigure.width, e->xconfigure.height);
}

void run(void) {
  XEvent ev;
  int w = win.w, h = win.h;
  fd_set rfd;
  int xfd = XConnectionNumber(xw.dpy), ttyfd, xev, drawing;
  struct timespec seltv, *tv, now, lastblink, trigger;
  double timeout;

  /* Waiting for window mapping */
  do {
    XNextEvent(xw.dpy, &ev);
    /*
     * This XFilterEvent call is required because of XOpenIM. It
     * does filter out the key event and some client message for
     * the input method too.
     */
    if (XFilterEvent(&ev, None))
      continue;
    if (ev.type == ConfigureNotify) {
      w = ev.xconfigure.width;
      h = ev.xconfigure.height;
    }
  } while (ev.type != MapNotify);

  ttyfd = ttynew(opt_line, shell, opt_io, opt_cmd);
  cresize(w, h);

  for (timeout = -1, drawing = 0, lastblink = (struct timespec){0};;) {
    FD_ZERO(&rfd);
    FD_SET(ttyfd, &rfd);
    FD_SET(xfd, &rfd);

    if (XPending(xw.dpy))
      timeout = 0; /* existing events might not set xfd */

    seltv.tv_sec = timeout / 1E3;
    seltv.tv_nsec = 1E6 * (timeout - 1E3 * seltv.tv_sec);
    tv = timeout >= 0 ? &seltv : NULL;

    if (pselect(MAX(xfd, ttyfd) + 1, &rfd, NULL, NULL, tv, NULL) < 0) {
      if (errno == EINTR)
        continue;
      die("select failed: %s\n", strerror(errno));
    }
    clock_gettime(CLOCK_MONOTONIC, &now);

    if (FD_ISSET(ttyfd, &rfd))
      ttyread();

    xev = 0;
    while (XPending(xw.dpy)) {
      xev = 1;
      XNextEvent(xw.dpy, &ev);
      if (XFilterEvent(&ev, None))
        continue;
      if (handler[ev.type])
        (handler[ev.type])(&ev);
    }

    /*
     * To reduce flicker and tearing, when new content or event
     * triggers drawing, we first wait a bit to ensure we got
     * everything, and if nothing new arrives - we draw.
     * We start with trying to wait minlatency ms. If more content
     * arrives sooner, we retry with shorter and shorter periods,
     * and eventually draw even without idle after maxlatency ms.
     * Typically this results in low latency while interacting,
     * maximum latency intervals during `cat huge.txt`, and perfect
     * sync with periodic updates from animations/key-repeats/etc.
     */
    if (FD_ISSET(ttyfd, &rfd) || xev) {
      if (!drawing) {
        trigger = now;
        drawing = 1;
      }
      timeout = (maxlatency - TIMEDIFF(now, trigger)) / maxlatency * minlatency;
      if (timeout > 0)
        continue; /* we have time, try to find idle */
    }

    /* idle detected or maxlatency exhausted -> draw */
    timeout = -1;
    if (blinktimeout && tattrset(ATTR_BLINK)) {
      timeout = blinktimeout - TIMEDIFF(now, lastblink);
      if (timeout <= 0) {
        if (-timeout > blinktimeout) /* start visible */
          win.mode |= MODE_BLINK;
        win.mode ^= MODE_BLINK;
        tsetdirtattr(ATTR_BLINK);
        lastblink = now;
        timeout = blinktimeout;
      }
    }

    draw();
    XFlush(xw.dpy);
    drawing = 0;
  }
}

void usage(void) {
  die("usage: %s [-aiv] [-c class] [-f font] [-g geometry]"
      " [-n name] [-o file]\n"
      "          [-T title] [-t title] [-w windowid]"
      " [[-e] command [args ...]]\n"
      "       %s [-aiv] [-c class] [-f font] [-g geometry]"
      " [-n name] [-o file]\n"
      "          [-T title] [-t title] [-w windowid] -l line"
      " [stty_args ...]\n",
      argv0, argv0);
}

int main(int argc, char *argv[]) {
  xw.l = xw.t = 0;
  xw.isfixed = False;
  xsetcursor(cursorshape);

  ARGBEGIN {
  case 'a':
    allowaltscreen = 0;
    break;
  case 'A':
    opt_alpha = EARGF(usage());
    break;
  case 'c':
    opt_class = EARGF(usage());
    break;
  case 'e':
    if (argc > 0)
      --argc, ++argv;
    goto run;
  case 'f':
    opt_font = EARGF(usage());
    break;
  case 'g':
    xw.gm = XParseGeometry(EARGF(usage()), &xw.l, &xw.t, &cols, &rows);
    break;
  case 'i':
    xw.isfixed = 1;
    break;
  case 'o':
    opt_io = EARGF(usage());
    break;
  case 'l':
    opt_line = EARGF(usage());
    break;
  case 'n':
    opt_name = EARGF(usage());
    break;
  case 't':
  case 'T':
    opt_title = EARGF(usage());
    break;
  case 'w':
    opt_embed = EARGF(usage());
    break;
  case 'v':
    die("%s " VERSION "\n", argv0);
    break;
  default:
    usage();
  }
  ARGEND;

run:
  if (argc > 0) /* eat all remaining arguments */
    opt_cmd = argv;

  if (!opt_title)
    opt_title = (opt_line || !opt_cmd) ? "st" : opt_cmd[0];

  setlocale(LC_CTYPE, "");
  XSetLocaleModifiers("");
  cols = MAX(cols, 1);
  rows = MAX(rows, 1);
  tnew(cols, rows);
  xinit(cols, rows);
  xsetenv();
  selinit();
  run();

  return 0;
}