xref: /dragonfly/games/hack/hack.pager.c (revision 71126e33) 
1 /* Copyright (c) Stichting Mathematisch Centrum, Amsterdam, 1985. */
2 /* hack.pager.c - version 1.0.3 */
3 /* $FreeBSD: src/games/hack/hack.pager.c,v 1.7 1999/11/16 02:57:09 billf Exp $ */
4 /* $DragonFly: src/games/hack/hack.pager.c,v 1.3 2004/11/06 12:29:17 eirikn Exp $ */
5 
6 /* This file contains the command routine dowhatis() and a pager. */
7 /* Also readmail() and doshell(), and generally the things that
8    contact the outside world. */
9 
10 #include	<sys/types.h>
11 #include	<sys/signal.h>
12 #include	<stdio.h>
13 #include        <stdlib.h>
14 #include        <unistd.h>
15 #include "hack.h"
16 extern int CO, LI;	/* usually COLNO and ROWNO+2 */
17 extern char *CD;
18 extern char quitchars[];
19 void done1();
20 
21 dowhatis()
22 {
23 	FILE *fp;
24 	char bufr[BUFSZ+6];
25 	char *buf = &bufr[6], *ep, q;
26 	extern char readchar();
27 
28 	if(!(fp = fopen(DATAFILE, "r")))
29 		pline("Cannot open data file!");
30 	else {
31 		pline("Specify what? ");
32 		q = readchar();
33 		if(q != '\t')
34 		while(fgets(buf,BUFSZ,fp))
35 		    if(*buf == q) {
36 			ep = index(buf, '\n');
37 			if(ep) *ep = 0;
38 			/* else: bad data file */
39 			/* Expand tab 'by hand' */
40 			if(buf[1] == '\t'){
41 				buf = bufr;
42 				buf[0] = q;
43 				(void) strncpy(buf+1, "       ", 7);
44 			}
45 			pline(buf);
46 			if(ep[-1] == ';') {
47 				pline("More info? ");
48 				if(readchar() == 'y') {
49 					page_more(fp,1); /* does fclose() */
50 					return(0);
51 				}
52 			}
53 			(void) fclose(fp); 	/* kopper@psuvax1 */
54 			return(0);
55 		    }
56 		pline("I've never heard of such things.");
57 		(void) fclose(fp);
58 	}
59 	return(0);
60 }
61 
62 /* make the paging of a file interruptible */
63 static int got_intrup;
64 
65 void
66 intruph(){
67 	got_intrup++;
68 }
69 
70 /* simple pager, also used from dohelp() */
71 page_more(fp,strip)
72 FILE *fp;
73 int strip;	/* nr of chars to be stripped from each line (0 or 1) */
74 {
75 	char *bufr, *ep;
76 	sig_t prevsig = signal(SIGINT, intruph);
77 
78 	set_pager(0);
79 	bufr = (char *) alloc((unsigned) CO);
80 	bufr[CO-1] = 0;
81 	while(fgets(bufr,CO-1,fp) && (!strip || *bufr == '\t') && !got_intrup){
82 		ep = index(bufr, '\n');
83 		if(ep)
84 			*ep = 0;
85 		if(page_line(bufr+strip)) {
86 			set_pager(2);
87 			goto ret;
88 		}
89 	}
90 	set_pager(1);
91 ret:
92 	free(bufr);
93 	(void) fclose(fp);
94 	(void) signal(SIGINT, prevsig);
95 	got_intrup = 0;
96 }
97 
98 static boolean whole_screen = TRUE;
99 #define	PAGMIN	12	/* minimum # of lines for page below level map */
100 
101 set_whole_screen() {	/* called in termcap as soon as LI is known */
102 	whole_screen = (LI-ROWNO-2 <= PAGMIN || !CD);
103 }
104 
105 #ifdef NEWS
106 readnews() {
107 	int ret;
108 
109 	whole_screen = TRUE;	/* force a docrt(), our first */
110 	ret = page_file(NEWS, TRUE);
111 	set_whole_screen();
112 	return(ret);		/* report whether we did docrt() */
113 }
114 #endif /* NEWS */
115 
116 set_pager(mode)
117 int mode;	/* 0: open  1: wait+close  2: close */
118 {
119 	static boolean so;
120 	if(mode == 0) {
121 		if(!whole_screen) {
122 			/* clear topline */
123 			clrlin();
124 			/* use part of screen below level map */
125 			curs(1, ROWNO+4);
126 		} else {
127 			cls();
128 		}
129 		so = flags.standout;
130 		flags.standout = 1;
131 	} else {
132 		if(mode == 1) {
133 			curs(1, LI);
134 			more();
135 		}
136 		flags.standout = so;
137 		if(whole_screen)
138 			docrt();
139 		else {
140 			curs(1, ROWNO+4);
141 			cl_eos();
142 		}
143 	}
144 }
145 
146 page_line(s)		/* returns 1 if we should quit */
147 char *s;
148 {
149 	extern char morc;
150 
151 	if(cury == LI-1) {
152 		if(!*s)
153 			return(0);	/* suppress blank lines at top */
154 		putchar('\n');
155 		cury++;
156 		cmore("q\033");
157 		if(morc) {
158 			morc = 0;
159 			return(1);
160 		}
161 		if(whole_screen)
162 			cls();
163 		else {
164 			curs(1, ROWNO+4);
165 			cl_eos();
166 		}
167 	}
168 	puts(s);
169 	cury++;
170 	return(0);
171 }
172 
173 /*
174  * Flexible pager: feed it with a number of lines and it will decide
175  * whether these should be fed to the pager above, or displayed in a
176  * corner.
177  * Call:
178  *	cornline(0, title or 0)	: initialize
179  *	cornline(1, text)	: add text to the chain of texts
180  *	cornline(2, morcs)	: output everything and cleanup
181  *	cornline(3, 0)		: cleanup
182  */
183 
184 cornline(mode, text)
185 int mode;
186 char *text;
187 {
188 	static struct line {
189 		struct line *next_line;
190 		char *line_text;
191 	} *texthead, *texttail;
192 	static int maxlen;
193 	static int linect;
194 	struct line *tl;
195 
196 	if(mode == 0) {
197 		texthead = 0;
198 		maxlen = 0;
199 		linect = 0;
200 		if(text) {
201 			cornline(1, text);	/* title */
202 			cornline(1, "");	/* blank line */
203 		}
204 		return;
205 	}
206 
207 	if(mode == 1) {
208 	    int len;
209 
210 	    if(!text) return;	/* superfluous, just to be sure */
211 	    linect++;
212 	    len = strlen(text);
213 	    if(len > maxlen)
214 		maxlen = len;
215 	    tl = (struct line *)
216 		alloc((unsigned)(len + sizeof(struct line) + 1));
217 	    tl->next_line = 0;
218 	    tl->line_text = (char *)(tl + 1);
219 	    (void) strcpy(tl->line_text, text);
220 	    if(!texthead)
221 		texthead = tl;
222 	    else
223 		texttail->next_line = tl;
224 	    texttail = tl;
225 	    return;
226 	}
227 
228 	/* --- now we really do it --- */
229 	if(mode == 2 && linect == 1)			    /* topline only */
230 		pline(texthead->line_text);
231 	else
232 	if(mode == 2) {
233 	    int curline, lth;
234 
235 	    if(flags.toplin == 1) more();	/* ab@unido */
236 	    remember_topl();
237 
238 	    lth = CO - maxlen - 2;		   /* Use full screen width */
239 	    if (linect < LI && lth >= 10) {		     /* in a corner */
240 		home ();
241 		cl_end ();
242 		flags.toplin = 0;
243 		curline = 1;
244 		for (tl = texthead; tl; tl = tl->next_line) {
245 		    curs (lth, curline);
246 		    if(curline > 1)
247 			cl_end ();
248 		    putsym(' ');
249 		    putstr (tl->line_text);
250 		    curline++;
251 		}
252 		curs (lth, curline);
253 		cl_end ();
254 		cmore (text);
255 		home ();
256 		cl_end ();
257 		docorner (lth, curline-1);
258 	    } else {					/* feed to pager */
259 		set_pager(0);
260 		for (tl = texthead; tl; tl = tl->next_line) {
261 		    if (page_line (tl->line_text)) {
262 			set_pager(2);
263 			goto cleanup;
264 		    }
265 		}
266 		if(text) {
267 			cgetret(text);
268 			set_pager(2);
269 		} else
270 			set_pager(1);
271 	    }
272 	}
273 
274 cleanup:
275 	while(tl = texthead) {
276 		texthead = tl->next_line;
277 		free((char *) tl);
278 	}
279 }
280 
281 dohelp()
282 {
283 	char c;
284 
285 	pline ("Long or short help? ");
286 	while (((c = readchar ()) != 'l') && (c != 's') && !index(quitchars,c))
287 		bell ();
288 	if (!index(quitchars, c))
289 		(void) page_file((c == 'l') ? HELP : SHELP, FALSE);
290 	return(0);
291 }
292 
293 page_file(fnam, silent)	/* return: 0 - cannot open fnam; 1 - otherwise */
294 char *fnam;
295 boolean silent;
296 {
297 #ifdef DEF_PAGER			/* this implies that UNIX is defined */
298       {
299 	/* use external pager; this may give security problems */
300 
301 	int fd = open(fnam, 0);
302 
303 	if(fd < 0) {
304 		if(!silent) pline("Cannot open %s.", fnam);
305 		return(0);
306 	}
307 	if(child(1)){
308 		extern char *catmore;
309 
310 		/* Now that child() does a setuid(getuid()) and a chdir(),
311 		   we may not be able to open file fnam anymore, so make
312 		   it stdin. */
313 		(void) close(0);
314 		if(dup(fd)) {
315 			if(!silent) printf("Cannot open %s as stdin.\n", fnam);
316 		} else {
317 			execl(catmore, "page", (char *) 0);
318 			if(!silent) printf("Cannot exec %s.\n", catmore);
319 		}
320 		exit(1);
321 	}
322 	(void) close(fd);
323       }
324 #else /* DEF_PAGER */
325       {
326 	FILE *f;			/* free after Robert Viduya */
327 
328 	if ((f = fopen (fnam, "r")) == (FILE *) 0) {
329 		if(!silent) {
330 			home(); perror (fnam); flags.toplin = 1;
331 			pline ("Cannot open %s.", fnam);
332 		}
333 		return(0);
334 	}
335 	page_more(f, 0);
336       }
337 #endif /* DEF_PAGER */
338 
339 	return(1);
340 }
341 
342 #ifdef UNIX
343 #ifdef SHELL
344 dosh(){
345 char *str;
346 	if(child(0)) {
347 		if(str = getenv("SHELL"))
348 			execl(str, str, (char *) 0);
349 		else
350 			execl("/bin/sh", "sh", (char *) 0);
351 		pline("sh: cannot execute.");
352 		exit(1);
353 	}
354 	return(0);
355 }
356 #endif /* SHELL */
357 
358 #ifdef NOWAITINCLUDE
359 union wait {		/* used only for the cast  (union wait *) 0  */
360 	int w_status;
361 	struct {
362 		unsigned short w_Termsig:7;
363 		unsigned short w_Coredump:1;
364 		unsigned short w_Retcode:8;
365 	} w_T;
366 };
367 
368 #else
369 
370 #ifdef BSD
371 #include	<sys/wait.h>
372 #else
373 #include	<wait.h>
374 #endif /* BSD */
375 #endif /* NOWAITINCLUDE */
376 
377 child(wt) {
378 	int status;
379 	int f;
380 
381 	f = fork();
382 	if(f == 0){		/* child */
383 		settty((char *) 0);		/* also calls end_screen() */
384 		/* revoke */
385 		setgid(getgid());
386 #ifdef CHDIR
387 		(void) chdir(getenv("HOME"));
388 #endif /* CHDIR */
389 		return(1);
390 	}
391 	if(f == -1) {	/* cannot fork */
392 		pline("Fork failed. Try again.");
393 		return(0);
394 	}
395 	/* fork succeeded; wait for child to exit */
396 	(void) signal(SIGINT,SIG_IGN);
397 	(void) signal(SIGQUIT,SIG_IGN);
398 	(void) wait(&status);
399 	gettty();
400 	setftty();
401 	(void) signal(SIGINT,done1);
402 #ifdef WIZARD
403 	if(wizard) (void) signal(SIGQUIT,SIG_DFL);
404 #endif /* WIZARD */
405 	if(wt) getret();
406 	docrt();
407 	return(0);
408 }
409 #endif /* UNIX */
410