freebsd-src/contrib/less/output.c
Paul Saab a5f0fb151d Import the [now] dual licensed version 3.5.4 of less. It is
distributed under your choice of the GPL or a BSD style license.

Reviewed by:	peter
Obtained from:	http://home.flash.net/~marknu/less/
2000-05-22 09:53:22 +00:00

462 lines
8.2 KiB
C

/*
* Copyright (C) 1984-2000 Mark Nudelman
*
* You may distribute under the terms of either the GNU General Public
* License or the Less License, as specified in the README file.
*
* For more information about less, or for information on how to
* contact the author, see the README file.
*/
/*
* High level routines dealing with the output to the screen.
*/
#include "less.h"
#if MSDOS_COMPILER==WIN32C
#include "windows.h"
#endif
public int errmsgs; /* Count of messages displayed by error() */
public int need_clr;
public int final_attr;
extern int sigs;
extern int sc_width;
extern int so_s_width, so_e_width;
extern int screen_trashed;
extern int any_display;
extern int is_tty;
/*
* 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;
}
final_attr = curr_attr;
}
static char obuf[OUTBUF_SIZE];
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;
n = ob - obuf;
if (n == 0)
return;
#if MSDOS_COMPILER==WIN32C
if (is_tty && any_display)
{
char *p;
char *op;
DWORD nwritten = 0;
CONSOLE_SCREEN_BUFFER_INFO scr;
DWORD nchars;
COORD cpos;
WORD nm_attr;
int olen;
extern HANDLE con_out;
extern int nm_fg_color;
extern int nm_bg_color;
#define MAKEATTR(fg,bg) ((WORD)((fg)|((bg)<<4)))
*ob = '\0';
olen = ob - obuf;
/*
* To avoid color problems, if we're scrolling the screen,
* we write only up to the char that causes the scroll,
* (a newline or a char in the last column), then fill
* the bottom line with the "normal" attribute, then
* write the rest.
* When Windows scrolls, it takes the attributes for the
* new line from the first char of the (previously)
* bottom line.
*
* {{ This still doesn't work correctly in all cases! }}
*/
nm_attr = MAKEATTR(nm_fg_color, nm_bg_color);
for (op = obuf; *op != '\0'; )
{
GetConsoleScreenBufferInfo(con_out, &scr);
/* Find the next newline. */
p = strchr(op, '\n');
if (p == NULL &&
scr.dwCursorPosition.X + olen >= sc_width)
{
/*
* No newline, but writing in the
* last column causes scrolling.
*/
p = op + sc_width - scr.dwCursorPosition.X - 1;
}
if (scr.dwCursorPosition.Y != scr.srWindow.Bottom ||
p == NULL)
{
/* Write the entire buffer. */
WriteConsole(con_out, op, olen,
&nwritten, NULL);
op += olen;
} else
{
/* Write only up to the scrolling char. */
WriteConsole(con_out, op, p - op + 1,
&nwritten, NULL);
cpos.X = 0;
cpos.Y = scr.dwCursorPosition.Y;
FillConsoleOutputAttribute(con_out, nm_attr,
sc_width, cpos, &nchars);
olen -= p - op + 1;
op = p + 1;
}
}
ob = obuf;
return;
}
#else
#if MSDOS_COMPILER==MSOFTC
if (is_tty && any_display)
{
*ob = '\0';
_outtext(obuf);
ob = obuf;
return;
}
#else
#if MSDOS_COMPILER==BORLANDC || MSDOS_COMPILER==DJGPPC
if (is_tty && any_display)
{
*ob = '\0';
cputs(obuf);
ob = obuf;
return;
}
#endif
#endif
#endif
fd = (any_display) ? 1 : 2;
if (write(fd, obuf, n) != n)
screen_trashed = 1;
ob = obuf;
}
/*
* Output a character.
*/
public int
putchr(c)
int c;
{
if (need_clr)
{
need_clr = 0;
clear_bot();
}
#if MSDOS_COMPILER
if (c == '\n' && is_tty)
{
/* remove_top(1); */
putchr('\r');
}
#else
#ifdef _OSK
if (c == '\n' && is_tty) /* In OS-9, '\n' == 0x0D */
putchr(0x0A);
#endif
#endif
/*
* Some versions of flush() write to *ob, so we must flush
* when we are still one char from the end of obuf.
*/
if (ob >= &obuf[sizeof(obuf)-1])
flush();
*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];
neg = (num < 0);
if (neg)
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
less_printf(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);
}
/*
* Get a RETURN.
* If some other non-trivial char is pressed, unget it, so it will
* become the next command.
*/
public void
get_return()
{
int c;
#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
}
/*
* 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 col = 0;
static char return_to_continue[] = " (press RETURN)";
errmsgs++;
if (any_display && is_tty)
{
clear_bot();
so_enter();
col += so_s_width;
}
col += less_printf(fmt, parg);
if (!(any_display && is_tty))
{
putchr('\n');
return;
}
putstr(return_to_continue);
so_exit();
col += sizeof(return_to_continue) + so_e_width;
get_return();
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) less_printf(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 && is_tty)
clear_bot();
(void) less_printf(fmt, parg);
c = getchr();
if (!(any_display && is_tty))
{
putchr('\n');
return (c);
}
lower_left();
if (col >= sc_width)
screen_trashed = 1;
flush();
return (c);
}