1/*-
2 * Copyright (c) 1993, 1994
3 *	The Regents of the University of California.  All rights reserved.
4 * Copyright (c) 1993, 1994, 1995, 1996
5 *	Keith Bostic.  All rights reserved.
6 *
7 * See the LICENSE file for redistribution information.
8 */
9
10#include "config.h"
11
12#ifndef lint
13static const char sccsid[] = "$Id: cl_read.c,v 10.30 2012/07/12 18:28:58 zy Exp $";
14#endif /* not lint */
15
16#include <sys/types.h>
17#include <sys/queue.h>
18#include <sys/select.h>
19
20#include <bitstring.h>
21#include <errno.h>
22#include <fcntl.h>
23#include <signal.h>
24#include <stdio.h>
25#include <stdlib.h>
26#include <string.h>
27#include <termios.h>
28#include <unistd.h>
29
30#include "../common/common.h"
31#include "../ex/script.h"
32#include "cl.h"
33
34/* Pollution by Solaris curses. */
35#undef columns
36#undef lines
37
38static input_t	cl_read(SCR *,
39    u_int32_t, char *, size_t, int *, struct timeval *);
40static int	cl_resize(SCR *, size_t, size_t);
41
42/*
43 * cl_event --
44 *	Return a single event.
45 *
46 * PUBLIC: int cl_event(SCR *, EVENT *, u_int32_t, int);
47 */
48int
49cl_event(SCR *sp, EVENT *evp, u_int32_t flags, int ms)
50{
51	struct timeval t, *tp;
52	CL_PRIVATE *clp;
53	size_t lines, columns;
54	int changed, nr = 0;
55	CHAR_T *wp;
56	size_t wlen;
57	int rc;
58
59	/*
60	 * Queue signal based events.  We never clear SIGHUP or SIGTERM events,
61	 * so that we just keep returning them until the editor dies.
62	 */
63	clp = CLP(sp);
64retest:	if (LF_ISSET(EC_INTERRUPT) || F_ISSET(clp, CL_SIGINT)) {
65		if (F_ISSET(clp, CL_SIGINT)) {
66			F_CLR(clp, CL_SIGINT);
67			evp->e_event = E_INTERRUPT;
68		} else
69			evp->e_event = E_TIMEOUT;
70		return (0);
71	}
72	if (F_ISSET(clp, CL_SIGHUP | CL_SIGTERM | CL_SIGWINCH)) {
73		if (F_ISSET(clp, CL_SIGHUP)) {
74			evp->e_event = E_SIGHUP;
75			return (0);
76		}
77		if (F_ISSET(clp, CL_SIGTERM)) {
78			evp->e_event = E_SIGTERM;
79			return (0);
80		}
81		if (F_ISSET(clp, CL_SIGWINCH)) {
82			F_CLR(clp, CL_SIGWINCH);
83			if (cl_ssize(sp, 1, &lines, &columns, &changed))
84				return (1);
85			if (changed) {
86				(void)cl_resize(sp, lines, columns);
87				evp->e_event = E_WRESIZE;
88				return (0);
89			}
90			/* No real change, ignore the signal. */
91		}
92	}
93
94	/* Set timer. */
95	if (ms == 0)
96		tp = NULL;
97	else {
98		t.tv_sec = ms / 1000;
99		t.tv_usec = (ms % 1000) * 1000;
100		tp = &t;
101	}
102
103	/* Read input characters. */
104read:
105	switch (cl_read(sp, LF_ISSET(EC_QUOTED | EC_RAW),
106	    clp->ibuf + clp->skip, SIZE(clp->ibuf) - clp->skip, &nr, tp)) {
107	case INP_OK:
108		rc = INPUT2INT5(sp, clp->cw, clp->ibuf, nr + clp->skip,
109				wp, wlen);
110		evp->e_csp = wp;
111		evp->e_len = wlen;
112		evp->e_event = E_STRING;
113		if (rc < 0) {
114		    int n = -rc;
115		    memmove(clp->ibuf, clp->ibuf + nr + clp->skip - n, n);
116		    clp->skip = n;
117		    if (wlen == 0)
118			goto read;
119		} else if (rc == 0)
120		    clp->skip = 0;
121		else
122		    msgq(sp, M_ERR, "323|Invalid input. Truncated.");
123		break;
124	case INP_EOF:
125		evp->e_event = E_EOF;
126		break;
127	case INP_ERR:
128		evp->e_event = E_ERR;
129		break;
130	case INP_INTR:
131		goto retest;
132	case INP_TIMEOUT:
133		evp->e_event = E_TIMEOUT;
134		break;
135	default:
136		abort();
137	}
138	return (0);
139}
140
141/*
142 * cl_read --
143 *	Read characters from the input.
144 */
145static input_t
146cl_read(SCR *sp, u_int32_t flags, char *bp, size_t blen, int *nrp,
147    struct timeval *tp)
148{
149	struct termios term1, term2;
150	CL_PRIVATE *clp;
151	GS *gp;
152	fd_set rdfd;
153	input_t rval;
154	int maxfd, nr, term_reset;
155
156	gp = sp->gp;
157	clp = CLP(sp);
158	term_reset = 0;
159
160	/*
161	 * 1: A read from a file or a pipe.  In this case, the reads
162	 *    never timeout regardless.  This means that we can hang
163	 *    when trying to complete a map, but we're going to hang
164	 *    on the next read anyway.
165	 */
166	if (!F_ISSET(clp, CL_STDIN_TTY)) {
167		switch (nr = read(STDIN_FILENO, bp, blen)) {
168		case 0:
169			return (INP_EOF);
170		case -1:
171			goto err;
172		default:
173			*nrp = nr;
174			return (INP_OK);
175		}
176		/* NOTREACHED */
177	}
178
179	/*
180	 * 2: A read with an associated timeout, e.g., trying to complete
181	 *    a map sequence.  If input exists, we fall into #3.
182	 */
183	if (tp != NULL) {
184		FD_ZERO(&rdfd);
185		FD_SET(STDIN_FILENO, &rdfd);
186		switch (select(STDIN_FILENO + 1, &rdfd, NULL, NULL, tp)) {
187		case 0:
188			return (INP_TIMEOUT);
189		case -1:
190			goto err;
191		default:
192			break;
193		}
194	}
195
196	/*
197	 * The user can enter a key in the editor to quote a character.  If we
198	 * get here and the next key is supposed to be quoted, do what we can.
199	 * Reset the tty so that the user can enter a ^C, ^Q, ^S.  There's an
200	 * obvious race here, when the key has already been entered, but there's
201	 * nothing that we can do to fix that problem.
202	 *
203	 * The editor can ask for the next literal character even thought it's
204	 * generally running in line-at-a-time mode.  Do what we can.
205	 */
206	if (LF_ISSET(EC_QUOTED | EC_RAW) && !tcgetattr(STDIN_FILENO, &term1)) {
207		term_reset = 1;
208		if (LF_ISSET(EC_QUOTED)) {
209			term2 = term1;
210			term2.c_lflag &= ~ISIG;
211			term2.c_iflag &= ~(IXON | IXOFF);
212			(void)tcsetattr(STDIN_FILENO,
213			    TCSASOFT | TCSADRAIN, &term2);
214		} else
215			(void)tcsetattr(STDIN_FILENO,
216			    TCSASOFT | TCSADRAIN, &clp->vi_enter);
217	}
218
219	/*
220	 * 3: Wait for input.
221	 *
222	 * Select on the command input and scripting window file descriptors.
223	 * It's ugly that we wait on scripting file descriptors here, but it's
224	 * the only way to keep from locking out scripting windows.
225	 */
226	if (F_ISSET(gp, G_SCRWIN)) {
227loop:		FD_ZERO(&rdfd);
228		FD_SET(STDIN_FILENO, &rdfd);
229		maxfd = STDIN_FILENO;
230		if (F_ISSET(sp, SC_SCRIPT)) {
231			FD_SET(sp->script->sh_master, &rdfd);
232			if (sp->script->sh_master > maxfd)
233				maxfd = sp->script->sh_master;
234		}
235		switch (select(maxfd + 1, &rdfd, NULL, NULL, NULL)) {
236		case 0:
237			abort();
238		case -1:
239			goto err;
240		default:
241			break;
242		}
243		if (!FD_ISSET(STDIN_FILENO, &rdfd)) {
244			if (sscr_input(sp))
245				return (INP_ERR);
246			goto loop;
247		}
248	}
249
250	/*
251	 * 4: Read the input.
252	 *
253	 * !!!
254	 * What's going on here is some scary stuff.  Ex runs the terminal in
255	 * canonical mode.  So, the <newline> character terminating a line of
256	 * input is returned in the buffer, but a trailing <EOF> character is
257	 * not similarly included.  As ex uses 0<EOF> and ^<EOF> as autoindent
258	 * commands, it has to see the trailing <EOF> characters to determine
259	 * the difference between the user entering "0ab" and "0<EOF>ab".  We
260	 * leave an extra slot in the buffer, so that we can add a trailing
261	 * <EOF> character if the buffer isn't terminated by a <newline>.  We
262	 * lose if the buffer is too small for the line and exactly N characters
263	 * are entered followed by an <EOF> character.
264	 */
265#define	ONE_FOR_EOF	1
266	switch (nr = read(STDIN_FILENO, bp, blen - ONE_FOR_EOF)) {
267	case  0:				/* EOF. */
268		/*
269		 * ^D in canonical mode returns a read of 0, i.e. EOF.  EOF is
270		 * a valid command, but we don't want to loop forever because
271		 * the terminal driver is returning EOF because the user has
272		 * disconnected. The editor will almost certainly try to write
273		 * something before this fires, which should kill us, but You
274		 * Never Know.
275		 */
276		if (++clp->eof_count < 50) {
277			bp[0] = clp->orig.c_cc[VEOF];
278			*nrp = 1;
279			rval = INP_OK;
280
281		} else
282			rval = INP_EOF;
283		break;
284	case -1:				/* Error or interrupt. */
285err:		if (errno == EINTR)
286			rval = INP_INTR;
287		else {
288			rval = INP_ERR;
289			msgq(sp, M_SYSERR, "input");
290		}
291		break;
292	default:				/* Input characters. */
293		if (F_ISSET(sp, SC_EX) && bp[nr - 1] != '\n')
294			bp[nr++] = clp->orig.c_cc[VEOF];
295		*nrp = nr;
296		clp->eof_count = 0;
297		rval = INP_OK;
298		break;
299	}
300
301	/* Restore the terminal state if it was modified. */
302	if (term_reset)
303		(void)tcsetattr(STDIN_FILENO, TCSASOFT | TCSADRAIN, &term1);
304	return (rval);
305}
306
307/*
308 * cl_resize --
309 *	Reset the options for a resize event.
310 */
311static int
312cl_resize(SCR *sp, size_t lines, size_t columns)
313{
314	ARGS *argv[2], a, b;
315	CHAR_T b1[1024];
316
317	a.bp = b1;
318	b.bp = NULL;
319	a.len = b.len = 0;
320	argv[0] = &a;
321	argv[1] = &b;
322
323	a.len = SPRINTF(b1, sizeof(b1), L("lines=%lu"), (u_long)lines);
324	if (opts_set(sp, argv, NULL))
325		return (1);
326	a.len = SPRINTF(b1, sizeof(b1), L("columns=%lu"), (u_long)columns);
327	if (opts_set(sp, argv, NULL))
328		return (1);
329	return (0);
330}
331