FAQ

@@ -2,14 +2,12 @@
 
 Use the excellent tool of [utmp](https://git.suckless.org/utmp/) for this task.
 
-
 ## Some _random program_ complains that st is unknown/not recognised/unsupported/whatever!
 
 It means that st doesn’t have any terminfo entry on your system. Chances are
 you did not `make install`. If you just want to test it without installing it,
 you can manually run `tic -sx st.info`.
 
-
 ## Nothing works, and nothing is said about an unknown terminal!
 
 * Some programs just assume they’re running in xterm i.e. they don’t rely on
@@ -17,7 +15,6 @@ you can manually run `tic -sx st.info`.
 * Some programs don’t complain about the lacking st description and default to
   another terminal. In that case see the question about terminfo.
 
-
 ## How do I scroll back up?
 
 * Using a terminal multiplexer.
@@ -26,13 +23,11 @@ you can manually run `tic -sx st.info`.
 * Using the excellent tool of [scroll](https://git.suckless.org/scroll/).
 * Using the scrollback [patch](https://st.suckless.org/patches/scrollback/).
 
-
 ## I would like to have utmp and/or scroll functionality by default
 
 You can add the absolute patch of both programs in your config.h
 file. You only have to modify the value of utmp and scroll variables.
 
-
 ## Why doesn't the Del key work in some programs?
 
 Taken from the terminfo manpage:
@@ -88,14 +83,12 @@ If you are using zsh, then read the zsh FAQ
 
 Putting these lines into your .zshrc will fix the problems.
 
-
 ## How can I use meta in 8bit mode?
 
 St supports meta in 8bit mode, but the default terminfo entry doesn't
 use this capability. If you want it, you have to use the 'st-meta' value
 in TERM.
 
-
 ## I cannot compile st in OpenBSD
 
 OpenBSD lacks librt, despite it being mandatory in POSIX
@@ -104,7 +97,6 @@ If you want to compile st for OpenBSD you have to remove -lrt from config.mk, an
 st will compile without any loss of functionality, because all the functions are
 included in libc on this platform.
 
-
 ## The Backspace Case
 
 St is emulating the Linux way of handling backspace being delete and delete being
@@ -166,60 +158,19 @@ terminal users wants its backspace to be how he feels it:
 	[1] http://www.ibb.net/~anne/keyboard.html
 	[2] http://www.tldp.org/HOWTO/Keyboard-and-Console-HOWTO-5.html
 
-
 ## But I really want the old grumpy behaviour of my terminal
 
 Apply [1].
 
 [1] https://st.suckless.org/patches/delkey
 
+## Why do images not work in st (in programs such as w3m)?
 
-## Why do images not work in st using the w3m image hack?
+This is a terrible hack that overdraws an image on top of the terminal emulator
-
+window. It also relies on a very specific way the terminal draws it's contents.
-w3mimg uses a hack that draws an image on top of the terminal emulator Drawable
-window. The hack relies on the terminal to use a single buffer to draw its
-contents directly.
-
-st uses double-buffered drawing so the image is quickly replaced and may show a
-short flicker effect.
-
-Below is a patch example to change st double-buffering to a single Drawable
-buffer.
-
-diff --git a/x.c b/x.c
---- a/x.c
-+++ b/x.c
-@@ -732,10 +732,6 @@ 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,
--			DefaultDepth(xw.dpy, xw.scr));
--	XftDrawChange(xw.draw, xw.buf);
- 	xclear(0, 0, win.w, win.h);
- 
- 	/* resize to new width */
-@@ -1148,8 +1144,7 @@ xinit(int cols, int rows)
- 	gcvalues.graphics_exposures = False;
- 	dc.gc = XCreateGC(xw.dpy, parent, GCGraphicsExposures,
- 			&gcvalues);
--	xw.buf = XCreatePixmap(xw.dpy, xw.win, win.w, win.h,
--			DefaultDepth(xw.dpy, xw.scr));
-+	xw.buf = xw.win;
- 	XSetForeground(xw.dpy, dc.gc, dc.col[defaultbg].pixel);
- 	XFillRectangle(xw.dpy, xw.buf, dc.gc, 0, 0, win.w, win.h);
- 
-@@ -1632,8 +1627,6 @@ xdrawline(Line line, int x1, int y1, int x2)
- 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);
 
+A more proper (but limited way) would be using sixels. Which st doesn't
+support.
 
 ## BadLength X error in Xft when trying to render emoji
 

LICENSE

@@ -1,6 +1,6 @@
 MIT/X Consortium License
 
-© 2014-2020 Hiltjo Posthuma <hiltjo at codemadness dot org>
+© 2014-2018 Hiltjo Posthuma <hiltjo at codemadness dot org>
 © 2018 Devin J. Pohly <djpohly at gmail dot com>
 © 2014-2017 Quentin Rameau <quinq at fifth dot space>
 © 2009-2012 Aurélien APTEL <aurelien dot aptel at gmail dot com>

config.def.h

@@ -43,18 +43,9 @@ static unsigned int tripleclicktimeout = 600;
 /* alt screens */
 int allowaltscreen = 1;
 
-/* allow certain non-interactive (insecure) window operations such as:
+/* frames per second st should at maximum draw to the screen */
-   setting the clipboard text */
+static unsigned int xfps = 120;
-int allowwindowops = 0;
+static unsigned int actionfps = 30;
-
-/*
- * draw latency range in ms - from new content/keypress/etc until drawing.
- * within this range, st draws when content stops arriving (idle). mostly it's
- * near minlatency, but it waits longer for slow updates to avoid partial draw.
- * low minlatency will tear/flicker more, as it can "detect" idle too early.
- */
-static double minlatency = 8;
-static double maxlatency = 33;
 
 /*
  * blinking timeout (set to 0 to disable blinking) for the terminal blinking
@@ -179,9 +170,7 @@ static uint forcemousemod = ShiftMask;
 static MouseShortcut mshortcuts[] = {
 	/* mask                 button   function        argument       release */
 	{ XK_ANY_MOD,           Button2, selpaste,       {.i = 0},      1 },
-	{ ShiftMask,            Button4, ttysend,        {.s = "\033[5;2~"} },
 	{ XK_ANY_MOD,           Button4, ttysend,        {.s = "\031"} },
-	{ ShiftMask,            Button5, ttysend,        {.s = "\033[6;2~"} },
 	{ XK_ANY_MOD,           Button5, ttysend,        {.s = "\005"} },
 };
 

config.mk

@@ -1,5 +1,5 @@
 # st version
-VERSION = 0.8.4
+VERSION = 0.8.2
 
 # Customize below to fit your system
 
@@ -28,8 +28,8 @@ STLDFLAGS = $(LIBS) $(LDFLAGS)
 # OpenBSD:
 #CPPFLAGS = -DVERSION=\"$(VERSION)\" -D_XOPEN_SOURCE=600 -D_BSD_SOURCE
 #LIBS = -L$(X11LIB) -lm -lX11 -lutil -lXft \
-#       `$(PKG_CONFIG) --libs fontconfig` \
+#       `pkg-config --libs fontconfig` \
-#       `$(PKG_CONFIG) --libs freetype2`
+#       `pkg-config --libs freetype2`
 
 # compiler and linker
 # CC = c99

st.c

@@ -38,7 +38,7 @@
 
 /* macros */
 #define IS_SET(flag)		((term.mode & (flag)) != 0)
-#define ISCONTROLC0(c)		(BETWEEN(c, 0, 0x1f) || (c) == 0x7f)
+#define ISCONTROLC0(c)		(BETWEEN(c, 0, 0x1f) || (c) == '\177')
 #define ISCONTROLC1(c)		(BETWEEN(c, 0x80, 0x9f))
 #define ISCONTROL(c)		(ISCONTROLC0(c) || ISCONTROLC1(c))
 #define ISDELIM(u)		(u && wcschr(worddelimiters, u))
@@ -51,6 +51,7 @@ enum term_mode {
 	MODE_ECHO        = 1 << 4,
 	MODE_PRINT       = 1 << 5,
 	MODE_UTF8        = 1 << 6,
+	MODE_SIXEL       = 1 << 7,
 };
 
 enum cursor_movement {
@@ -77,11 +78,12 @@ enum charset {
 enum escape_state {
 	ESC_START      = 1,
 	ESC_CSI        = 2,
-	ESC_STR        = 4,  /* DCS, OSC, PM, APC */
+	ESC_STR        = 4,  /* OSC, PM, APC */
 	ESC_ALTCHARSET = 8,
 	ESC_STR_END    = 16, /* a final string was encountered */
 	ESC_TEST       = 32, /* Enter in test mode */
 	ESC_UTF8       = 64,
+	ESC_DCS        =128,
 };
 
 typedef struct {
@@ -127,7 +129,6 @@ typedef struct {
 	int charset;  /* current charset */
 	int icharset; /* selected charset for sequence */
 	int *tabs;
-	Rune lastc;   /* last printed char outside of sequence, 0 if control */
 } Term;
 
 /* CSI Escape sequence structs */
@@ -633,8 +634,7 @@ getsel(void)
 		 * st.
 		 * FIXME: Fix the computer world.
 		 */
-		if ((y < sel.ne.y || lastx >= linelen) &&
+		if ((y < sel.ne.y || lastx >= linelen) && !(last->mode & ATTR_WRAP))
-		    (!(last->mode & ATTR_WRAP) || sel.type == SEL_RECTANGULAR))
 			*ptr++ = '\n';
 	}
 	*ptr = 0;
@@ -730,7 +730,7 @@ sigchld(int a)
 		die("child exited with status %d\n", WEXITSTATUS(stat));
 	else if (WIFSIGNALED(stat))
 		die("child terminated due to signal %d\n", WTERMSIG(stat));
-	_exit(0);
+	exit(0);
 }
 
 void
@@ -841,6 +841,7 @@ ttyread(void)
 		if (buflen > 0)
 			memmove(buf, buf + written, buflen);
 		return ret;
+
 	}
 }
 
@@ -1104,17 +1105,27 @@ selscroll(int orig, int n)
 	if (sel.ob.x == -1)
 		return;
 
-	if (BETWEEN(sel.nb.y, orig, term.bot) != BETWEEN(sel.ne.y, orig, term.bot)) {
+	if (BETWEEN(sel.ob.y, orig, term.bot) || BETWEEN(sel.oe.y, orig, term.bot)) {
+		if ((sel.ob.y += n) > term.bot || (sel.oe.y += n) < term.top) {
 			selclear();
-	} else if (BETWEEN(sel.nb.y, orig, term.bot)) {
+			return;
-		sel.ob.y += n;
-		sel.oe.y += n;
-		if (sel.ob.y < term.top || sel.ob.y > term.bot ||
-		    sel.oe.y < term.top || sel.oe.y > term.bot) {
-			selclear();
-		} else {
-			selnormalize();
 		}
+		if (sel.type == SEL_RECTANGULAR) {
+			if (sel.ob.y < term.top)
+				sel.ob.y = term.top;
+			if (sel.oe.y > term.bot)
+				sel.oe.y = term.bot;
+		} else {
+			if (sel.ob.y < term.top) {
+				sel.ob.y = term.top;
+				sel.ob.x = 0;
+			}
+			if (sel.oe.y > term.bot) {
+				sel.oe.y = term.bot;
+				sel.oe.x = term.col;
+			}
+		}
+		selnormalize();
 	}
 }
 
@@ -1646,12 +1657,6 @@ csihandle(void)
 		if (csiescseq.arg[0] == 0)
 			ttywrite(vtiden, strlen(vtiden), 0);
 		break;
-	case 'b': /* REP -- if last char is printable print it <n> more times */
-		DEFAULT(csiescseq.arg[0], 1);
-		if (term.lastc)
-			while (csiescseq.arg[0]-- > 0)
-				tputc(term.lastc);
-		break;
 	case 'C': /* CUF -- Cursor <n> Forward */
 	case 'a': /* HPR -- Cursor <n> Forward */
 		DEFAULT(csiescseq.arg[0], 1);
@@ -1859,7 +1864,7 @@ strhandle(void)
 				xsettitle(strescseq.args[1]);
 			return;
 		case 52:
-			if (narg > 2 && allowwindowops) {
+			if (narg > 2) {
 				dec = base64dec(strescseq.args[2]);
 				if (dec) {
 					xsetsel(dec);
@@ -1895,6 +1900,7 @@ strhandle(void)
 		xsettitle(strescseq.args[0]);
 		return;
 	case 'P': /* DCS -- Device Control String */
+		term.mode |= ESC_DCS;
 	case '_': /* APC -- Application Program Command */
 	case '^': /* PM -- Privacy Message */
 		return;
@@ -2088,9 +2094,12 @@ tdectest(char c)
 void
 tstrsequence(uchar c)
 {
+	strreset();
+
 	switch (c) {
 	case 0x90:   /* DCS -- Device Control String */
 		c = 'P';
+		term.esc |= ESC_DCS;
 		break;
 	case 0x9f:   /* APC -- Application Program Command */
 		c = '_';
@@ -2102,7 +2111,6 @@ tstrsequence(uchar c)
 		c = ']';
 		break;
 	}
-	strreset();
 	strescseq.type = c;
 	term.esc |= ESC_STR;
 }
@@ -2145,7 +2153,6 @@ tcontrolcode(uchar ascii)
 		return;
 	case '\032': /* SUB */
 		tsetchar('?', &term.c.attr, term.c.x, term.c.y);
-		/* FALLTHROUGH */
 	case '\030': /* CAN */
 		csireset();
 		break;
@@ -2300,14 +2307,16 @@ tputc(Rune u)
 	Glyph *gp;
 
 	control = ISCONTROL(u);
-	if (u < 127 || !IS_SET(MODE_UTF8)) {
+	if (!IS_SET(MODE_UTF8) && !IS_SET(MODE_SIXEL)) {
 		c[0] = u;
 		width = len = 1;
 	} else {
 		len = utf8encode(u, c);
-		if (!control && (width = wcwidth(u)) == -1)
+		if (!control && (width = wcwidth(u)) == -1) {
+			memcpy(c, "\357\277\275", 4); /* UTF_INVALID */
 			width = 1;
 		}
+	}
 
 	if (IS_SET(MODE_PRINT))
 		tprinter(c, len);
@@ -2321,11 +2330,23 @@ tputc(Rune u)
 	if (term.esc & ESC_STR) {
 		if (u == '\a' || u == 030 || u == 032 || u == 033 ||
 		   ISCONTROLC1(u)) {
-			term.esc &= ~(ESC_START|ESC_STR);
+			term.esc &= ~(ESC_START|ESC_STR|ESC_DCS);
+			if (IS_SET(MODE_SIXEL)) {
+				/* TODO: render sixel */;
+				term.mode &= ~MODE_SIXEL;
+				return;
+			}
 			term.esc |= ESC_STR_END;
 			goto check_control_code;
 		}
 
+		if (IS_SET(MODE_SIXEL)) {
+			/* TODO: implement sixel mode */
+			return;
+		}
+		if (term.esc&ESC_DCS && strescseq.len == 0 && u == 'q')
+			term.mode |= MODE_SIXEL;
+
 		if (strescseq.len+len >= strescseq.siz) {
 			/*
 			 * Here is a bug in terminals. If the user never sends
@@ -2362,8 +2383,6 @@ check_control_code:
 		/*
 		 * control codes are not shown ever
 		 */
-		if (!term.esc)
-			term.lastc = 0;
 		return;
 	} else if (term.esc & ESC_START) {
 		if (term.esc & ESC_CSI) {
@@ -2394,7 +2413,7 @@ check_control_code:
 		 */
 		return;
 	}
-	if (selected(term.c.x, term.c.y))
+	if (sel.ob.x != -1 && BETWEEN(term.c.y, sel.ob.y, sel.oe.y))
 		selclear();
 
 	gp = &term.line[term.c.y][term.c.x];
@@ -2413,7 +2432,6 @@ check_control_code:
 	}
 
 	tsetchar(u, &term.c.attr, term.c.x, term.c.y);
-	term.lastc = u;
 
 	if (width == 2) {
 		gp->mode |= ATTR_WIDE;
@@ -2437,7 +2455,7 @@ twrite(const char *buf, int buflen, int show_ctrl)
 	int n;
 
 	for (n = 0; n < buflen; n += charsize) {
-		if (IS_SET(MODE_UTF8)) {
+		if (IS_SET(MODE_UTF8) && !IS_SET(MODE_SIXEL)) {
 			/* process a complete utf8 char */
 			charsize = utf8decode(buf + n, &u, buflen - n);
 			if (charsize == 0)

st.h

@@ -118,7 +118,6 @@ extern char *stty_args;
 extern char *vtiden;
 extern wchar_t *worddelimiters;
 extern int allowaltscreen;
-extern int allowwindowops;
 extern char *termname;
 extern unsigned int tabspaces;
 extern unsigned int defaultfg;

st.info

@@ -158,7 +158,6 @@ st-mono| simpleterm monocolor,
 	rc=\E8,
 	rev=\E[7m,
 	ri=\EM,
-	rin=\E[%p1%dT,
 	ritm=\E[23m,
 	rmacs=\E(B,
 	rmcup=\E[?1049l,
@@ -184,8 +183,6 @@ st-mono| simpleterm monocolor,
 # XTerm extensions
 	rmxx=\E[29m,
 	smxx=\E[9m,
-# disabled rep for now: causes some issues with older ncurses versions.
-#	rep=%p1%c\E[%p2%{1}%-%db,
 # tmux extensions, see TERMINFO EXTENSIONS in tmux(1)
 	Tc,
 	Ms=\E]52;%p1%s;%p2%s\007,

x.c

@@ -1543,9 +1543,8 @@ xdrawcursor(int cx, int cy, Glyph g, int ox, int oy, Glyph og)
 	/* draw the new one */
 	if (IS_SET(MODE_FOCUSED)) {
 		switch (win.cursor) {
-		case 7: /* st extension */
+		case 7: /* st extension: snowman (U+2603) */
-			g.u = 0x2603; /* snowman (U+2603) */
+			g.u = 0x2603;
-			/* FALLTHROUGH */
 		case 0: /* Blinking Block */
 		case 1: /* Blinking Block (Default) */
 		case 2: /* Steady Block */
@@ -1707,7 +1706,8 @@ xsetmode(int set, unsigned int flags)
 int
 xsetcursor(int cursor)
 {
-	if (!BETWEEN(cursor, 0, 7)) /* 7: st extension */
+	DEFAULT(cursor, 1);
+	if (!BETWEEN(cursor, 0, 6))
 		return 1;
 	win.cursor = cursor;
 	return 0;
@@ -1884,9 +1884,10 @@ run(void)
 	XEvent ev;
 	int w = win.w, h = win.h;
 	fd_set rfd;
-	int xfd = XConnectionNumber(xw.dpy), ttyfd, xev, drawing;
+	int xfd = XConnectionNumber(xw.dpy), xev, blinkset = 0, dodraw = 0;
-	struct timespec seltv, *tv, now, lastblink, trigger;
+	int ttyfd;
-	double timeout;
+	struct timespec drawtimeout, *tv = NULL, now, last, lastblink;
+	long deltatime;
 
 	/* Waiting for window mapping */
 	do {
@@ -1907,31 +1908,51 @@ run(void)
 	ttyfd = ttynew(opt_line, shell, opt_io, opt_cmd);
 	cresize(w, h);
 
-	for (timeout = -1, drawing = 0, lastblink = (struct timespec){0};;) {
+	clock_gettime(CLOCK_MONOTONIC, &last);
+	lastblink = last;
+
+	for (xev = actionfps;;) {
 		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)) {
-
-		if (FD_ISSET(ttyfd, &rfd))
 			ttyread();
+			if (blinktimeout) {
+				blinkset = tattrset(ATTR_BLINK);
+				if (!blinkset)
+					MODBIT(win.mode, 0, MODE_BLINK);
+			}
+		}
 
-		xev = 0;
+		if (FD_ISSET(xfd, &rfd))
+			xev = actionfps;
+
+		clock_gettime(CLOCK_MONOTONIC, &now);
+		drawtimeout.tv_sec = 0;
+		drawtimeout.tv_nsec =  (1000 * 1E6)/ xfps;
+		tv = &drawtimeout;
+
+		dodraw = 0;
+		if (blinktimeout && TIMEDIFF(now, lastblink) > blinktimeout) {
+			tsetdirtattr(ATTR_BLINK);
+			win.mode ^= MODE_BLINK;
+			lastblink = now;
+			dodraw = 1;
+		}
+		deltatime = TIMEDIFF(now, last);
+		if (deltatime > 1000 / (xev ? xfps : actionfps)) {
+			dodraw = 1;
+			last = now;
+		}
+
+		if (dodraw) {
 			while (XPending(xw.dpy)) {
-			xev = 1;
 				XNextEvent(xw.dpy, &ev);
 				if (XFilterEvent(&ev, None))
 					continue;
@@ -1939,45 +1960,30 @@ run(void)
 					(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;
+
+			if (xev && !FD_ISSET(xfd, &rfd))
+				xev--;
+			if (!FD_ISSET(ttyfd, &rfd) && !FD_ISSET(xfd, &rfd)) {
+				if (blinkset) {
+					if (TIMEDIFF(now, lastblink) \
+							> blinktimeout) {
+						drawtimeout.tv_nsec = 1000;
+					} else {
+						drawtimeout.tv_nsec = (1E6 * \
+							(blinktimeout - \
+							TIMEDIFF(now,
+								lastblink)));
+					}
+					drawtimeout.tv_sec = \
+					    drawtimeout.tv_nsec / 1E9;
+					drawtimeout.tv_nsec %= (long)1E9;
+				} else {
+					tv = NULL;
+				}
+			}
+		}
 	}
 }
 
@@ -1999,7 +2005,7 @@ main(int argc, char *argv[])
 {
 	xw.l = xw.t = 0;
 	xw.isfixed = False;
-	xsetcursor(cursorshape);
+	win.cursor = cursorshape;
 
 	ARGBEGIN {
 	case 'a':