OpenBSD-4.6/games/hack/hack.pager.c
/* $OpenBSD: hack.pager.c,v 1.17 2009/06/03 14:47:47 chl Exp $ */
/*
* Copyright (c) 1985, Stichting Centrum voor Wiskunde en Informatica,
* Amsterdam
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met:
*
* - Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* - 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.
*
* - Neither the name of the Stichting Centrum voor Wiskunde en
* Informatica, nor the names of its contributors may be used to endorse or
* promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT OWNER
* 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.
*/
/*
* Copyright (c) 1982 Jay Fenlason <hack@gnu.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.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED ``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.
*/
#ifndef lint
static const char rcsid[] = "$OpenBSD: hack.pager.c,v 1.17 2009/06/03 14:47:47 chl Exp $";
#endif /* not lint */
/* This file contains the command routine dowhatis() and a pager. */
/* Also readmail() and doshell(), and generally the things that
contact the outside world. */
#include <sys/types.h>
#include <signal.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "hack.h"
extern int CO, LI; /* usually COLNO and ROWNO+2 */
extern char *CD;
extern char quitchars[];
static void page_more(FILE *, int);
int
dowhatis()
{
FILE *fp;
char bufr[BUFSZ+6];
char *buf = &bufr[6], q;
size_t len;
extern char readchar();
if (!(fp = fopen(DATAFILE, "r")))
pline("Cannot open data file!");
else {
pline("Specify what? ");
q = readchar();
if (q != '\t')
while (fgets(buf,BUFSZ,fp))
if (*buf == q) {
len = strcspn(buf, "\n");
/* bad data file */
if (len == 0)
continue;
buf[len] = '\0';
/* Expand tab 'by hand' */
if (buf[1] == '\t'){
buf = bufr;
buf[0] = q;
(void) strncpy(buf+1, " ", 7);
len = strlen(buf);
}
pline(buf);
if (buf[len - 1] == ';') {
pline("More info? ");
if (readchar() == 'y') {
page_more(fp,1); /* does fclose() */
return(0);
}
}
(void) fclose(fp); /* kopper@psuvax1 */
return(0);
}
pline("I've never heard of such things.");
(void) fclose(fp);
}
return(0);
}
/* make the paging of a file interruptible */
static int got_intrup;
void
intruph(int notused)
{
got_intrup++;
}
/* simple pager, also used from dohelp() */
/* strip: nr of chars to be stripped from each line (0 or 1) */
static void
page_more(FILE *fp, int strip)
{
char *bufr;
sig_t prevsig = signal(SIGINT, intruph);
set_pager(0);
bufr = (char *) alloc((unsigned) CO);
while (fgets(bufr, CO, fp) && (!strip || *bufr == '\t') &&
!got_intrup) {
bufr[strcspn(bufr, "\n")] = '\0';
if (*bufr == '\0' || page_line(bufr+strip)) {
set_pager(2);
goto ret;
}
}
set_pager(1);
ret:
free(bufr);
(void) fclose(fp);
(void) signal(SIGINT, prevsig);
got_intrup = 0;
}
static boolean whole_screen = TRUE;
#define PAGMIN 12 /* minimum # of lines for page below level map */
void
set_whole_screen()
{ /* called in termcap as soon as LI is known */
whole_screen = (LI-ROWNO-2 <= PAGMIN || !CD);
}
#ifdef NEWS
int
readnews()
{
int ret;
whole_screen = TRUE; /* force a docrt(), our first */
ret = page_file(NEWS, TRUE);
set_whole_screen();
return(ret); /* report whether we did docrt() */
}
#endif /* NEWS */
/* 0: open 1: wait+close 2: close */
void
set_pager(int mode)
{
static boolean so;
if(mode == 0) {
if(!whole_screen) {
/* clear topline */
clrlin();
/* use part of screen below level map */
curs(1, ROWNO+4);
} else {
cls();
}
so = flags.standout;
flags.standout = 1;
} else {
if(mode == 1) {
curs(1, LI);
more();
}
flags.standout = so;
if(whole_screen)
docrt();
else {
curs(1, ROWNO+4);
cl_eos();
}
}
}
int
page_line(char *s) /* returns 1 if we should quit */
{
extern char morc;
if(cury == LI-1) {
if(!*s)
return(0); /* suppress blank lines at top */
putchar('\n');
cury++;
cmore("q\033");
if(morc) {
morc = 0;
return(1);
}
if(whole_screen)
cls();
else {
curs(1, ROWNO+4);
cl_eos();
}
}
puts(s);
cury++;
return(0);
}
/*
* Flexible pager: feed it with a number of lines and it will decide
* whether these should be fed to the pager above, or displayed in a
* corner.
* Call:
* cornline(0, title or 0) : initialize
* cornline(1, text) : add text to the chain of texts
* cornline(2, morcs) : output everything and cleanup
* cornline(3, 0) : cleanup
*/
void
cornline(int mode, char *text)
{
static struct line {
struct line *next_line;
char *line_text;
} *texthead, *texttail;
static int maxlen;
static int linect;
struct line *tl;
if(mode == 0) {
texthead = 0;
maxlen = 0;
linect = 0;
if(text) {
cornline(1, text); /* title */
cornline(1, ""); /* blank line */
}
return;
}
if(mode == 1) {
int len;
if(!text) return; /* superfluous, just to be sure */
linect++;
len = strlen(text);
if(len > maxlen)
maxlen = len;
tl = (struct line *)
alloc((unsigned)(len + sizeof(struct line) + 1));
tl->next_line = 0;
tl->line_text = (char *)(tl + 1);
(void) strlcpy(tl->line_text, text, len + 1);
if(!texthead)
texthead = tl;
else
texttail->next_line = tl;
texttail = tl;
return;
}
/* --- now we really do it --- */
if(mode == 2 && linect == 1) /* topline only */
pline(texthead->line_text);
else
if(mode == 2) {
int curline, lth;
if(flags.toplin == 1) more(); /* ab@unido */
remember_topl();
lth = CO - maxlen - 2; /* Use full screen width */
if (linect < LI && lth >= 10) { /* in a corner */
home();
cl_end();
flags.toplin = 0;
curline = 1;
for (tl = texthead; tl; tl = tl->next_line) {
curs(lth, curline);
if(curline > 1)
cl_end();
putsym(' ');
putstr (tl->line_text);
curline++;
}
curs(lth, curline);
cl_end();
cmore(text);
home();
cl_end();
docorner(lth, curline-1);
} else { /* feed to pager */
set_pager(0);
for (tl = texthead; tl; tl = tl->next_line) {
if (page_line (tl->line_text)) {
set_pager(2);
goto cleanup;
}
}
if(text) {
cgetret(text);
set_pager(2);
} else
set_pager(1);
}
}
cleanup:
while ((tl = texthead)) {
texthead = tl->next_line;
free((char *) tl);
}
}
int
dohelp()
{
char c;
pline ("Long or short help? ");
while (((c = readchar ()) != 'l') && (c != 's') && !strchr(quitchars,c))
hackbell ();
if (!strchr(quitchars, c))
(void) page_file((c == 'l') ? HELP : SHELP, FALSE);
return(0);
}
/* return: 0 - cannot open fnam; 1 - otherwise */
int
page_file(char *fnam, boolean silent)
{
#ifdef DEF_PAGER /* this implies that UNIX is defined */
{
/* use external pager; this may give security problems */
int fd = open(fnam, O_RDONLY);
if(fd < 0) {
if(!silent) pline("Cannot open %s.", fnam);
return(0);
}
if(child(1)){
extern char *catmore;
/* Now that child() does a setuid(getuid()) and a chdir(),
we may not be able to open file fnam anymore, so make
it stdin. */
(void) close(0);
if(dup(fd)) {
if(!silent) printf("Cannot open %s as stdin.\n", fnam);
} else {
execl(catmore, "page", (char *) 0);
if(!silent) printf("Cannot exec %s.\n", catmore);
}
exit(1);
}
(void) close(fd);
}
#else /* DEF_PAGER */
{
FILE *f; /* free after Robert Viduya */
if ((f = fopen (fnam, "r")) == (FILE *) 0) {
if(!silent) {
home(); perror (fnam); flags.toplin = 1;
pline ("Cannot open %s.", fnam);
}
return(0);
}
page_more(f, 0);
}
#endif /* DEF_PAGER */
return(1);
}
#ifdef UNIX
#ifdef SHELL
int
dosh()
{
char *str;
if(child(0)) {
if ((str = getenv("SHELL")))
execl(str, str, (char *) 0);
else
execl("/bin/sh", "sh", (char *) 0);
pline("sh: cannot execute.");
exit(1);
}
return(0);
}
#endif /* SHELL */
#include <sys/wait.h>
int
child(int wt)
{
int status;
int f;
char *home;
gid_t gid;
f = fork();
if(f == 0){ /* child */
settty((char *) 0); /* also calls end_screen() */
/* revoke privs */
gid = getgid();
setresgid(gid, gid, gid);
#ifdef CHDIR
home = getenv("HOME");
if (home == NULL || *home == '\0')
home = "/";
(void) chdir(home);
#endif /* CHDIR */
return(1);
}
if(f == -1) { /* cannot fork */
pline("Fork failed. Try again.");
return(0);
}
/* fork succeeded; wait for child to exit */
(void) signal(SIGINT,SIG_IGN);
(void) signal(SIGQUIT,SIG_IGN);
(void) wait(&status);
gettty();
setftty();
(void) signal(SIGINT,done1);
#ifdef WIZARD
if(wizard) (void) signal(SIGQUIT,SIG_DFL);
#endif /* WIZARD */
if(wt) getret();
docrt();
return(0);
}
#endif /* UNIX */