Import of unmolested less-290.

1 files changed, 363 insertions, 0 deletions

diff --git a/usr.bin/less/output.c b/usr.bin/less/output.c
new file mode 100644
index 00000000000..dbe180073a5
--- /dev/null
+++ b/usr.bin/less/output.c
@@ -0,0 +1,363 @@
+/*
+ * Copyright (c) 1984,1985,1989,1994,1995  Mark Nudelman
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice in the documentation and/or other materials provided with 
+ *    the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
+ * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR 
+ * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE 
+ * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN 
+ * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+
+/*
+ * High level routines dealing with the output to the screen.
+ */
+
+#include "less.h"
+
+public int errmsgs;	/* Count of messages displayed by error() */
+public int need_clr;
+
+extern int sigs;
+extern int sc_width;
+extern int so_s_width, so_e_width;
+extern int screen_trashed;
+extern int any_display;
+
+/*
+ * Display the line which is in the line buffer.
+ */
+	public void
+put_line()
+{
+	register int c;
+	register int i;
+	int a;
+	int curr_attr;
+
+	if (ABORT_SIGS())
+	{
+		/*
+		 * Don't output if a signal is pending.
+		 */
+		screen_trashed = 1;
+		return;
+	}
+
+	curr_attr = AT_NORMAL;
+
+	for (i = 0;  (c = gline(i, &a)) != '\0';  i++)
+	{
+		if (a != curr_attr)
+		{
+			/*
+			 * Changing attributes.
+			 * Display the exit sequence for the old attribute
+			 * and the enter sequence for the new one.
+			 */
+			switch (curr_attr)
+			{
+			case AT_UNDERLINE:	ul_exit();	break;
+			case AT_BOLD:		bo_exit();	break;
+			case AT_BLINK:		bl_exit();	break;
+			case AT_STANDOUT:	so_exit();	break;
+			}
+			switch (a)
+			{
+			case AT_UNDERLINE:	ul_enter();	break;
+			case AT_BOLD:		bo_enter();	break;
+			case AT_BLINK:		bl_enter();	break;
+			case AT_STANDOUT:	so_enter();	break;
+			}
+			curr_attr = a;
+		}
+		if (curr_attr == AT_INVIS)
+			continue;
+		if (c == '\b')
+			putbs();
+		else
+			putchr(c);
+	}
+
+	switch (curr_attr)
+	{
+	case AT_UNDERLINE:	ul_exit();	break;
+	case AT_BOLD:		bo_exit();	break;
+	case AT_BLINK:		bl_exit();	break;
+	case AT_STANDOUT:	so_exit();	break;
+	}
+}
+
+static char obuf[1024];
+static char *ob = obuf;
+
+/*
+ * Flush buffered output.
+ *
+ * If we haven't displayed any file data yet,
+ * output messages on error output (file descriptor 2),
+ * otherwise output on standard output (file descriptor 1).
+ *
+ * This has the desirable effect of producing all
+ * error messages on error output if standard output
+ * is directed to a file.  It also does the same if
+ * we never produce any real output; for example, if
+ * the input file(s) cannot be opened.  If we do
+ * eventually produce output, code in edit() makes
+ * sure these messages can be seen before they are
+ * overwritten or scrolled away.
+ */
+	public void
+flush()
+{
+	register int n;
+	register int fd;
+
+#if MSOFTC
+	*ob = '\0';
+	_outtext(obuf);
+	ob = obuf;
+#else
+	n = ob - obuf;
+	if (n == 0)
+		return;
+	fd = (any_display) ? 1 : 2;
+	if (write(fd, obuf, n) != n)
+		screen_trashed = 1;
+	ob = obuf;
+#endif
+}
+
+/*
+ * Output a character.
+ */
+	public int
+putchr(c)
+	int c;
+{
+	if (ob >= &obuf[sizeof(obuf)])
+		flush();
+	if (need_clr)
+	{
+		need_clr = 0;
+		clear_bot();
+	}
+#if MSOFTC
+	if (c == '\n')
+		putchr('\r');
+#endif
+	*ob++ = c;
+	return (c);
+}
+
+/*
+ * Output a string.
+ */
+	public void
+putstr(s)
+	register char *s;
+{
+	while (*s != '\0')
+		putchr(*s++);
+}
+
+
+/*
+ * Output an integer in a given radix.
+ */
+	static int
+iprintnum(num, radix)
+	int num;
+	int radix;
+{
+	register char *s;
+	int r;
+	int neg;
+	char buf[10];
+
+	if (neg = (num < 0))
+		num = -num;
+
+	s = buf;
+	do
+	{
+		*s++ = (num % radix) + '0';
+	} while ((num /= radix) != 0);
+
+	if (neg)
+		*s++ = '-';
+	r = s - buf;
+
+	while (s > buf)
+		putchr(*--s);
+	return (r);
+}
+
+/*
+ * This function implements printf-like functionality
+ * using a more portable argument list mechanism than printf's.
+ */
+	static int
+iprintf(fmt, parg)
+	register char *fmt;
+	PARG *parg;
+{
+	register char *s;
+	register int n;
+	register int col;
+
+	col = 0;
+	while (*fmt != '\0')
+	{
+		if (*fmt != '%')
+		{
+			putchr(*fmt++);
+			col++;
+		} else
+		{
+			++fmt;
+			switch (*fmt++) {
+			case 's':
+				s = parg->p_string;
+				parg++;
+				while (*s != '\0')
+				{
+					putchr(*s++);
+					col++;
+				}
+				break;
+			case 'd':
+				n = parg->p_int;
+				parg++;
+				col += iprintnum(n, 10);
+				break;
+			}
+		}
+	}
+	return (col);
+}
+
+/*
+ * Output a message in the lower left corner of the screen
+ * and wait for carriage return.
+ */
+	public void
+error(fmt, parg)
+	char *fmt;
+	PARG *parg;
+{
+	int c;
+	int col = 0;
+	static char return_to_continue[] = "  (press RETURN)";
+
+	errmsgs++;
+
+	if (any_display)
+	{
+		clear_bot();
+		so_enter();
+		col += so_s_width;
+	}
+
+	col += iprintf(fmt, parg);
+
+	if (!any_display)
+	{
+		putchr('\n');
+		return;
+	}
+
+	putstr(return_to_continue);
+	so_exit();
+	col += sizeof(return_to_continue) + so_e_width;
+
+#if ONLY_RETURN
+	while ((c = getchr()) != '\n' && c != '\r')
+		bell();
+#else
+	c = getchr();
+	if (c != '\n' && c != '\r' && c != ' ' && c != READ_INTR)
+		ungetcc(c);
+#endif
+	lower_left();
+
+	if (col >= sc_width)
+		/*
+		 * Printing the message has probably scrolled the screen.
+		 * {{ Unless the terminal doesn't have auto margins,
+		 *    in which case we just hammered on the right margin. }}
+		 */
+		screen_trashed = 1;
+
+	flush();
+}
+
+static char intr_to_abort[] = "... (interrupt to abort)";
+
+/*
+ * Output a message in the lower left corner of the screen
+ * and don't wait for carriage return.
+ * Usually used to warn that we are beginning a potentially
+ * time-consuming operation.
+ */
+	public void
+ierror(fmt, parg)
+	char *fmt;
+	PARG *parg;
+{
+	clear_bot();
+	so_enter();
+	(void) iprintf(fmt, parg);
+	putstr(intr_to_abort);
+	so_exit();
+	flush();
+	need_clr = 1;
+}
+
+/*
+ * Output a message in the lower left corner of the screen
+ * and return a single-character response.
+ */
+	public int
+query(fmt, parg)
+	char *fmt;
+	PARG *parg;
+{
+	register int c;
+	int col = 0;
+
+	if (any_display)
+		clear_bot();
+
+	(void) iprintf(fmt, parg);
+	c = getchr();
+
+	if (!any_display)
+	{
+		putchr('\n');
+		return (c);
+	}
+
+	lower_left();
+	if (col >= sc_width)
+		screen_trashed = 1;
+	flush();
+
+	return (c);
+}