path: root/st.c

/* See LICENSE for licence details.  */
#include "st.h"

/* Globals */
DC dc;
XWindow xw;
Term term;
Escseq escseq;
int cmdfd;
int running;

void
die(const char *errstr, ...) {
	va_list ap;

	va_start(ap, errstr);
	vfprintf(stderr, errstr, ap);
	va_end(ap);
	exit(EXIT_FAILURE);
}

void
execsh(void) {
	char *args[3] = {SHELL, "-i", NULL};
	putenv("TERM=" TNAME);
	execvp(SHELL, args);
}

void
xbell(void) {   /* visual bell */
	XRectangle r = { 0, 0, xw.w, xw.h };
	XSetForeground(xw.dis, dc.gc, dc.col[BellCol]);
	XFillRectangles(xw.dis, xw.win, dc.gc, &r, 1);
	XFlush(xw.dis);
	usleep(30000);
	draw(SCredraw);
}

void
ttynew(void) {
	int m, s;
	pid_t pid;
	char *pts;

	if((m = posix_openpt(O_RDWR | O_NOCTTY)) < 0)
		die("openpt");
	if(grantpt(m) == -1)
		die("grandpt");
	if(unlockpt(m) == -1)
		die("unlockpt");
	if((pts = ptsname(m)) == NULL)
		die("ptsname");
	if((s = open(pts, O_RDWR | O_NOCTTY)) < 0)
		die("slave open");
	fcntl(s, F_SETFL, O_NDELAY);
	switch(pid = fork()) {
	case -1:
		die("fork");
		break;
	case 0:
		setsid(); /* create a new process group */
		dup2(s, STDIN_FILENO);
		dup2(s, STDOUT_FILENO);
		dup2(s, STDERR_FILENO);
		if(ioctl(s, TIOCSCTTY, NULL) < 0)
			die("slave TTIOCSTTY");
		execsh();
		break;
	default:
		close(s);
		cmdfd = m;
	}
}

void
dump(char c) {
	static int col;
	fprintf(stderr, " %02x %c ", c, isprint(c)?c:'.');
	if(++col % 10 == 0)
		fprintf(stderr, "\n");
}

void
ttyread(void) {
	char buf[BUFSIZ] = {0};
	int ret;

	switch(ret = read(cmdfd, buf, BUFSIZ)) {
	case -1: /* error or exit */
		/* XXX: be more precise */
		running = 0;
		break;
	default:
		tputs(buf, ret);
	}
}

void
ttywrite(char *s, size_t n) {
	if(write(cmdfd, s, n) == -1)
		die("write error on tty.");
}

void
ttyresize(int x, int y) {
	struct winsize w;

	w.ws_row = term.row;
	w.ws_col = term.col;
	w.ws_xpixel = w.ws_ypixel = 0;
	if(ioctl(cmdfd, TIOCSWINSZ, &w) < 0)
		fprintf(stderr, "Couldn't set window size: %m\n");
}

int
escfinal(char c) {
	if(escseq.len == 1)
		switch(c) {
		case '[':
		case ']':
		case '(':
			return 0;
		case '=':
		case '>':
		default:
			return 1;
		}
	else if(BETWEEN(c, 0x40, 0x7E))
		return 1;
	return 0;     
}

void
tcpos(int mode) {
	static int x = 0;
	static int y = 0;

	if(mode == CSsave)
		x = term.c.x, y = term.c.y;
	else if(mode == CSload)
		tmoveto(x, y);
}

void
tnew(int col, int row) {   /* screen size */
	term.row = row, term.col = col;
	term.top = 0, term.bot = term.row - 1;
	/* mode */
	term.mode = TMwrap;
	/* cursor */
	term.c.attr.mode = ATnone;
	term.c.attr.fg = DefaultFG;
	term.c.attr.bg = DefaultBG;
	term.c.x = term.c.y = 0;
	term.c.hidden = 0;
	/* allocate screen */
	term.line = calloc(term.row, sizeof(Line));
	for(row = 0 ; row < term.row; row++)
		term.line[row] = calloc(term.col, sizeof(Glyph));
}

void
tscroll(void) {
	Line temp = term.line[term.top];
	int i;

	for(i = term.top; i < term.bot; i++)
		term.line[i] = term.line[i+1];
	memset(temp, 0, sizeof(Glyph) * term.col);
	term.line[term.bot] = temp;
	xscroll();    
}

void
tnewline(void) {
	int y = term.c.y + 1;

	if(y > term.bot) {
		tscroll(), y = term.bot;
	}
	tmoveto(0, y);
}

int
escaddc(char c) {
	escseq.buf[escseq.len++] = c;
	if(escfinal(c) || escseq.len >= ESCSIZ) {
		escparse(), eschandle();
		return 0;
	}
	return 1;
}

void
escparse(void) {
	/* int noarg = 1; */
	char *p = escseq.buf;

	escseq.narg = 0;
	switch(escseq.pre = *p++) {
	case '[': /* CSI */
		if(*p == '?')
			escseq.priv = 1, p++;

		while(p < escseq.buf+escseq.len) {
			while(isdigit(*p)) {
				escseq.arg[escseq.narg] *= 10;
				escseq.arg[escseq.narg] += *(p++) - '0'/*, noarg = 0 */;
			}
			if(*p == ';')
				escseq.narg++, p++;
			else {
				escseq.mode = *p;
				escseq.narg++;
				return;
			}
		}
		break;
	case '(':
		/* XXX: graphic character set */
		break;
	}
}