199767f8919635c4928607450d9e0abb932109ceToomas Soome/*-
199767f8919635c4928607450d9e0abb932109ceToomas Soome * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
199767f8919635c4928607450d9e0abb932109ceToomas Soome * All rights reserved.
199767f8919635c4928607450d9e0abb932109ceToomas Soome *
199767f8919635c4928607450d9e0abb932109ceToomas Soome * Redistribution and use in source and binary forms, with or without
199767f8919635c4928607450d9e0abb932109ceToomas Soome * modification, are permitted provided that the following conditions
199767f8919635c4928607450d9e0abb932109ceToomas Soome * are met:
199767f8919635c4928607450d9e0abb932109ceToomas Soome * 1. Redistributions of source code must retain the above copyright
199767f8919635c4928607450d9e0abb932109ceToomas Soome * notice, this list of conditions and the following disclaimer.
199767f8919635c4928607450d9e0abb932109ceToomas Soome * 2. Redistributions in binary form must reproduce the above copyright
199767f8919635c4928607450d9e0abb932109ceToomas Soome * notice, this list of conditions and the following disclaimer in the
199767f8919635c4928607450d9e0abb932109ceToomas Soome * documentation and/or other materials provided with the distribution.
199767f8919635c4928607450d9e0abb932109ceToomas Soome *
199767f8919635c4928607450d9e0abb932109ceToomas Soome * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
199767f8919635c4928607450d9e0abb932109ceToomas Soome * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
199767f8919635c4928607450d9e0abb932109ceToomas Soome * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
199767f8919635c4928607450d9e0abb932109ceToomas Soome * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
199767f8919635c4928607450d9e0abb932109ceToomas Soome * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
199767f8919635c4928607450d9e0abb932109ceToomas Soome * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
199767f8919635c4928607450d9e0abb932109ceToomas Soome * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
199767f8919635c4928607450d9e0abb932109ceToomas Soome * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
199767f8919635c4928607450d9e0abb932109ceToomas Soome * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
199767f8919635c4928607450d9e0abb932109ceToomas Soome * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
199767f8919635c4928607450d9e0abb932109ceToomas Soome * SUCH DAMAGE.
199767f8919635c4928607450d9e0abb932109ceToomas Soome */
199767f8919635c4928607450d9e0abb932109ceToomas Soome/*
199767f8919635c4928607450d9e0abb932109ceToomas Soome * Simple paged-output and paged-viewing functions
199767f8919635c4928607450d9e0abb932109ceToomas Soome */
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome#include <sys/cdefs.h>
199767f8919635c4928607450d9e0abb932109ceToomas Soome__FBSDID("$FreeBSD$");
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome#include "stand.h"
199767f8919635c4928607450d9e0abb932109ceToomas Soome#include <string.h>
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soomestatic int p_maxlines = -1;
199767f8919635c4928607450d9e0abb932109ceToomas Soomestatic int p_freelines;
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soomestatic char *pager_prompt1 = " --more-- <space> page down <enter> line down <q> quit ";
199767f8919635c4928607450d9e0abb932109ceToomas Soomestatic char *pager_blank = " ";
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome/*
199767f8919635c4928607450d9e0abb932109ceToomas Soome * 'open' the pager
199767f8919635c4928607450d9e0abb932109ceToomas Soome */
199767f8919635c4928607450d9e0abb932109ceToomas Soomevoid
199767f8919635c4928607450d9e0abb932109ceToomas Soomepager_open(void)
199767f8919635c4928607450d9e0abb932109ceToomas Soome{
199767f8919635c4928607450d9e0abb932109ceToomas Soome int nlines;
199767f8919635c4928607450d9e0abb932109ceToomas Soome char *cp, *lp;
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome nlines = 24; /* sensible default */
199767f8919635c4928607450d9e0abb932109ceToomas Soome if ((cp = getenv("LINES")) != NULL) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome nlines = strtol(cp, &lp, 0);
199767f8919635c4928607450d9e0abb932109ceToomas Soome }
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome p_maxlines = nlines - 1;
199767f8919635c4928607450d9e0abb932109ceToomas Soome if (p_maxlines < 1)
199767f8919635c4928607450d9e0abb932109ceToomas Soome p_maxlines = 1;
199767f8919635c4928607450d9e0abb932109ceToomas Soome p_freelines = p_maxlines;
199767f8919635c4928607450d9e0abb932109ceToomas Soome}
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome/*
199767f8919635c4928607450d9e0abb932109ceToomas Soome * 'close' the pager
199767f8919635c4928607450d9e0abb932109ceToomas Soome */
199767f8919635c4928607450d9e0abb932109ceToomas Soomevoid
199767f8919635c4928607450d9e0abb932109ceToomas Soomepager_close(void)
199767f8919635c4928607450d9e0abb932109ceToomas Soome{
199767f8919635c4928607450d9e0abb932109ceToomas Soome p_maxlines = -1;
199767f8919635c4928607450d9e0abb932109ceToomas Soome}
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome/*
199767f8919635c4928607450d9e0abb932109ceToomas Soome * Emit lines to the pager; may not return until the user
199767f8919635c4928607450d9e0abb932109ceToomas Soome * has responded to the prompt.
199767f8919635c4928607450d9e0abb932109ceToomas Soome *
199767f8919635c4928607450d9e0abb932109ceToomas Soome * Will return nonzero if the user enters 'q' or 'Q' at the prompt.
199767f8919635c4928607450d9e0abb932109ceToomas Soome *
199767f8919635c4928607450d9e0abb932109ceToomas Soome * XXX note that this watches outgoing newlines (and eats them), but
199767f8919635c4928607450d9e0abb932109ceToomas Soome * does not handle wrap detection (req. count of columns).
199767f8919635c4928607450d9e0abb932109ceToomas Soome */
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soomeint
199767f8919635c4928607450d9e0abb932109ceToomas Soomepager_output(const char *cp)
199767f8919635c4928607450d9e0abb932109ceToomas Soome{
199767f8919635c4928607450d9e0abb932109ceToomas Soome int action;
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome if (cp == NULL)
199767f8919635c4928607450d9e0abb932109ceToomas Soome return(0);
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome for (;;) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome if (*cp == 0)
199767f8919635c4928607450d9e0abb932109ceToomas Soome return(0);
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome putchar(*cp); /* always emit character */
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome if (*(cp++) == '\n') { /* got a newline? */
199767f8919635c4928607450d9e0abb932109ceToomas Soome p_freelines--;
199767f8919635c4928607450d9e0abb932109ceToomas Soome if (p_freelines <= 0) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome printf("%s", pager_prompt1);
199767f8919635c4928607450d9e0abb932109ceToomas Soome action = 0;
199767f8919635c4928607450d9e0abb932109ceToomas Soome while (action == 0) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome switch(getchar()) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome case '\r':
199767f8919635c4928607450d9e0abb932109ceToomas Soome case '\n':
199767f8919635c4928607450d9e0abb932109ceToomas Soome p_freelines = 1;
199767f8919635c4928607450d9e0abb932109ceToomas Soome action = 1;
199767f8919635c4928607450d9e0abb932109ceToomas Soome break;
199767f8919635c4928607450d9e0abb932109ceToomas Soome case ' ':
199767f8919635c4928607450d9e0abb932109ceToomas Soome p_freelines = p_maxlines;
199767f8919635c4928607450d9e0abb932109ceToomas Soome action = 1;
199767f8919635c4928607450d9e0abb932109ceToomas Soome break;
199767f8919635c4928607450d9e0abb932109ceToomas Soome case 'q':
199767f8919635c4928607450d9e0abb932109ceToomas Soome case 'Q':
199767f8919635c4928607450d9e0abb932109ceToomas Soome action = 2;
199767f8919635c4928607450d9e0abb932109ceToomas Soome break;
199767f8919635c4928607450d9e0abb932109ceToomas Soome default:
199767f8919635c4928607450d9e0abb932109ceToomas Soome break;
199767f8919635c4928607450d9e0abb932109ceToomas Soome }
199767f8919635c4928607450d9e0abb932109ceToomas Soome }
199767f8919635c4928607450d9e0abb932109ceToomas Soome printf("\r%s\r", pager_blank);
199767f8919635c4928607450d9e0abb932109ceToomas Soome if (action == 2)
199767f8919635c4928607450d9e0abb932109ceToomas Soome return(1);
199767f8919635c4928607450d9e0abb932109ceToomas Soome }
199767f8919635c4928607450d9e0abb932109ceToomas Soome }
199767f8919635c4928607450d9e0abb932109ceToomas Soome }
199767f8919635c4928607450d9e0abb932109ceToomas Soome}
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome/*
199767f8919635c4928607450d9e0abb932109ceToomas Soome * Display from (fd).
199767f8919635c4928607450d9e0abb932109ceToomas Soome */
199767f8919635c4928607450d9e0abb932109ceToomas Soomeint
199767f8919635c4928607450d9e0abb932109ceToomas Soomepager_file(const char *fname)
199767f8919635c4928607450d9e0abb932109ceToomas Soome{
199767f8919635c4928607450d9e0abb932109ceToomas Soome char buf[80];
199767f8919635c4928607450d9e0abb932109ceToomas Soome size_t hmuch;
199767f8919635c4928607450d9e0abb932109ceToomas Soome int fd;
199767f8919635c4928607450d9e0abb932109ceToomas Soome int result;
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome if ((fd = open(fname, O_RDONLY)) == -1) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome printf("can't open '%s': %s\n", fname, strerror(errno));
199767f8919635c4928607450d9e0abb932109ceToomas Soome return(-1);
199767f8919635c4928607450d9e0abb932109ceToomas Soome }
199767f8919635c4928607450d9e0abb932109ceToomas Soome
199767f8919635c4928607450d9e0abb932109ceToomas Soome for (;;) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome hmuch = read(fd, buf, sizeof(buf) - 1);
199767f8919635c4928607450d9e0abb932109ceToomas Soome if (hmuch == -1) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome result = -1;
199767f8919635c4928607450d9e0abb932109ceToomas Soome break;
199767f8919635c4928607450d9e0abb932109ceToomas Soome }
199767f8919635c4928607450d9e0abb932109ceToomas Soome if (hmuch == 0) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome result = 0;
199767f8919635c4928607450d9e0abb932109ceToomas Soome break;
199767f8919635c4928607450d9e0abb932109ceToomas Soome }
199767f8919635c4928607450d9e0abb932109ceToomas Soome buf[hmuch] = 0;
199767f8919635c4928607450d9e0abb932109ceToomas Soome if (pager_output(buf)) {
199767f8919635c4928607450d9e0abb932109ceToomas Soome result = 1;
199767f8919635c4928607450d9e0abb932109ceToomas Soome break;
199767f8919635c4928607450d9e0abb932109ceToomas Soome }
199767f8919635c4928607450d9e0abb932109ceToomas Soome }
199767f8919635c4928607450d9e0abb932109ceToomas Soome close(fd);
199767f8919635c4928607450d9e0abb932109ceToomas Soome return(result);
199767f8919635c4928607450d9e0abb932109ceToomas Soome}