mirror of
https://git.FreeBSD.org/src.git
synced 2024-11-25 07:49:18 +00:00
159 lines
3.6 KiB
C
159 lines
3.6 KiB
C
/*-
|
|
* Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
|
|
* 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, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
|
|
*/
|
|
/*
|
|
* Simple paged-output and paged-viewing functions
|
|
*/
|
|
|
|
#include "stand.h"
|
|
#include <string.h>
|
|
|
|
static int p_maxlines = -1;
|
|
static int p_freelines;
|
|
|
|
static char *pager_prompt1 = " --more-- <space> page down <enter> line down <q> quit ";
|
|
static char *pager_blank = " ";
|
|
|
|
/*
|
|
* 'open' the pager
|
|
*/
|
|
void
|
|
pager_open(void)
|
|
{
|
|
int nlines;
|
|
char *cp, *lp;
|
|
|
|
nlines = 24; /* sensible default */
|
|
if ((cp = getenv("LINES")) != NULL) {
|
|
nlines = strtol(cp, &lp, 0);
|
|
}
|
|
|
|
p_maxlines = nlines - 1;
|
|
if (p_maxlines < 1)
|
|
p_maxlines = 1;
|
|
p_freelines = p_maxlines;
|
|
}
|
|
|
|
/*
|
|
* 'close' the pager
|
|
*/
|
|
void
|
|
pager_close(void)
|
|
{
|
|
p_maxlines = -1;
|
|
}
|
|
|
|
/*
|
|
* Emit lines to the pager; may not return until the user
|
|
* has responded to the prompt.
|
|
*
|
|
* Will return nonzero if the user enters 'q' or 'Q' at the prompt.
|
|
*
|
|
* XXX note that this watches outgoing newlines (and eats them), but
|
|
* does not handle wrap detection (req. count of columns).
|
|
*/
|
|
|
|
int
|
|
pager_output(const char *cp)
|
|
{
|
|
int action;
|
|
|
|
if (cp == NULL)
|
|
return(0);
|
|
|
|
for (;;) {
|
|
if (*cp == 0)
|
|
return(0);
|
|
|
|
putchar(*cp); /* always emit character */
|
|
|
|
if (*(cp++) == '\n') { /* got a newline? */
|
|
p_freelines--;
|
|
if (p_freelines <= 0) {
|
|
printf("%s", pager_prompt1);
|
|
action = 0;
|
|
while (action == 0) {
|
|
switch(getchar()) {
|
|
case '\r':
|
|
case '\n':
|
|
p_freelines = 1;
|
|
action = 1;
|
|
break;
|
|
case ' ':
|
|
p_freelines = p_maxlines;
|
|
action = 1;
|
|
break;
|
|
case 'q':
|
|
case 'Q':
|
|
action = 2;
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
printf("\r%s\r", pager_blank);
|
|
if (action == 2)
|
|
return(1);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Display from (fd).
|
|
*/
|
|
int
|
|
pager_file(const char *fname)
|
|
{
|
|
char buf[80];
|
|
size_t hmuch;
|
|
int fd;
|
|
int result;
|
|
|
|
if ((fd = open(fname, O_RDONLY)) == -1) {
|
|
printf("can't open '%s': %s\n", fname, strerror(errno));
|
|
return(-1);
|
|
}
|
|
|
|
for (;;) {
|
|
hmuch = read(fd, buf, sizeof(buf) - 1);
|
|
if (hmuch == -1) {
|
|
result = -1;
|
|
break;
|
|
}
|
|
if (hmuch == 0) {
|
|
result = 0;
|
|
break;
|
|
}
|
|
buf[hmuch] = 0;
|
|
if (pager_output(buf)) {
|
|
result = 1;
|
|
break;
|
|
}
|
|
}
|
|
close(fd);
|
|
return(result);
|
|
}
|