From: Mike Karels <karels@ucbvax.Berkeley.EDU>
Date: Thu, 12 Apr 1984 06:02:48 +0000 (-0800)
Subject: date and time created 84/04/11 15:02:48 by karels
X-Git-Tag: BSD-4_3-Snapshot-Development~10124
X-Git-Url: https://git.subgeniuskitty.com/unix-history/.git/commitdiff_plain/a07b5a3866282d3ae1f5f5dd7d3811f69b30dac7

date and time created 84/04/11 15:02:48 by karels

SCCS-vsn: usr.bin/talk/display.c 1.1
---

diff --git a/usr/src/usr.bin/talk/display.c b/usr/src/usr.bin/talk/display.c
new file mode 100644
index 0000000000..22615a00ec
--- /dev/null
+++ b/usr/src/usr.bin/talk/display.c
@@ -0,0 +1,170 @@
+/* $Header: display.c 1.2 83/04/23 02:09:33 moore Exp $ */
+
+/* The window 'manager', initializes curses and handles the actual
+ * displaying of text
+ */
+
+#include "talk.h"
+
+xwin_t my_win;
+xwin_t his_win;
+WINDOW *line_win;
+
+int curses_initialized = 0;
+
+    /* max HAS to be a function, it is called with
+     * a argument of the form --foo at least once.
+     */
+
+max(a,b)
+int a, b;
+{
+    if (a > b) {
+	return(a);
+    } else {
+	return(b);
+    }
+}
+
+/*
+ * Display some text on somebody's window, processing some control
+ * characters while we are at it.
+ */
+
+display(win, text, size)
+register xwin_t *win;
+register char *text;
+int size;
+{
+    register int i;
+    char cch;
+
+    for (i = 0; i < size; i++) {
+
+	if (*text == '\n') {
+	    xscroll(win, 0);
+	    text++;
+	    continue;
+	}
+
+	    /* erase character */
+
+	if (*text == win->cerase) {
+	    wmove(win->x_win, win->x_line, max(--win->x_col, 0));
+	    getyx(win->x_win, win->x_line, win->x_col);
+	    waddch(win->x_win, ' ');
+	    wmove(win->x_win, win->x_line, win->x_col);
+	    getyx(win->x_win, win->x_line, win->x_col);
+	    text++;
+	    continue;
+	}
+	/*
+	 * On word erase search backwards until we find
+	 * the beginning of a word or the beginning of
+	 * the line.
+	 */
+	if (*text == win->werase) {
+	    int endcol, xcol, i, c;
+
+	    endcol = win->x_col;
+	    xcol = endcol - 1;
+	    while (xcol >= 0) {
+		c = readwin(win->x_win, win->x_line, xcol);
+		if (c != ' ')
+			break;
+		xcol--;
+	    }
+	    while (xcol >= 0) {
+		c = readwin(win->x_win, win->x_line, xcol);
+		if (c == ' ')
+			break;
+		xcol--;
+	    }
+	    wmove(win->x_win, win->x_line, xcol + 1);
+	    for (i = xcol + 1; i < endcol; i++)
+		waddch(win->x_win, ' ');
+	    wmove(win->x_win, win->x_line, xcol + 1);
+	    getyx(win->x_win, win->x_line, win->x_col);
+	    continue;
+	}
+	    /* line kill */
+	if (*text == win->kill) {
+	    wmove(win->x_win, win->x_line, 0);
+	    wclrtoeol(win->x_win);
+	    getyx(win->x_win, win->x_line, win->x_col);
+	    text++;
+	    continue;
+	}
+	if (*text == '\f') {
+	    if (win == &my_win)
+		wrefresh(curscr);
+	    text++;
+	    continue;
+	}
+
+	if (win->x_col == COLS-1) {
+		/* check for wraparound */
+	    xscroll(win, 0);
+	}
+
+	if (*text < ' ' && *text != '\t') {
+	    waddch(win->x_win, '^');
+	    getyx(win->x_win, win->x_line, win->x_col);
+
+	    if (win->x_col == COLS-1) {
+		    /* check for wraparound */
+		xscroll(win, 0);
+	    }
+
+	    cch = (*text & 63) + 64;
+	    waddch(win->x_win, cch);
+	} else {
+	    waddch(win->x_win, *text);
+	}
+
+	getyx(win->x_win, win->x_line, win->x_col);
+	text++;
+
+    }
+wrefresh(win->x_win);
+}
+
+/*
+* Read the character at the indicated position in win
+*/
+readwin(win, line, col)
+WINDOW *win;
+{
+int oldline, oldcol;
+register int c;
+
+getyx(win, oldline, oldcol);
+wmove(win, line, col);
+c = winch(win);
+wmove(win, oldline, oldcol);
+return(c);
+}
+
+/*
+* Scroll a window, blanking out the line following the current line
+* so that the current position is obvious
+*/
+
+xscroll(win, flag)
+register xwin_t *win;
+int flag;
+{
+    if (flag == -1) {
+	wmove(win->x_win, 0, 0);
+	win->x_line = 0;
+	win->x_col = 0;
+	return;
+    }
+    win->x_line = (win->x_line + 1) % win->x_nlines;
+    win->x_col = 0;
+    wmove(win->x_win, win->x_line, win->x_col);
+    wclrtoeol(win->x_win);
+    wmove(win->x_win, (win->x_line + 1) % win->x_nlines, win->x_col);
+    wclrtoeol(win->x_win);
+    wmove(win->x_win, win->x_line, win->x_col);
+}