xref: /netbsd-src/external/bsd/nvi/dist/cl/cl_read.c (revision 2f698edb5c1cb2dcd9e762b0abb50c41dde8b6b7)
1 /*	$NetBSD: cl_read.c,v 1.3 2014/01/26 21:43:45 christos Exp $ */
2 /*-
3  * Copyright (c) 1993, 1994
4  *	The Regents of the University of California.  All rights reserved.
5  * Copyright (c) 1993, 1994, 1995, 1996
6  *	Keith Bostic.  All rights reserved.
7  *
8  * See the LICENSE file for redistribution information.
9  */
10 
11 #include "config.h"
12 
13 #include <sys/cdefs.h>
14 #if 0
15 #ifndef lint
16 static const char sccsid[] = "Id: cl_read.c,v 10.29 2001/08/18 21:51:59 skimo Exp  (Berkeley) Date: 2001/08/18 21:51:59 ";
17 #endif /* not lint */
18 #else
19 __RCSID("$NetBSD: cl_read.c,v 1.3 2014/01/26 21:43:45 christos Exp $");
20 #endif
21 
22 #include <sys/types.h>
23 #include <sys/queue.h>
24 #ifdef HAVE_SYS_SELECT_H
25 #include <sys/select.h>
26 #endif
27 #include <sys/time.h>
28 
29 #include <bitstring.h>
30 #include <errno.h>
31 #include <fcntl.h>
32 #include <signal.h>
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36 #include <termios.h>
37 #include <unistd.h>
38 
39 #include "../common/common.h"
40 #include "../ex/script.h"
41 #include "cl.h"
42 
43 /* Pollution by Solaris curses. */
44 #undef columns
45 #undef lines
46 
47 static input_t	cl_read __P((SCR *,
48     u_int32_t, char *, size_t, int *, struct timeval *));
49 static int	cl_resize __P((SCR *, size_t, size_t));
50 
51 /*
52  * cl_event --
53  *	Return a single event.
54  *
55  * PUBLIC: int cl_event __P((SCR *, EVENT *, u_int32_t, int));
56  */
57 int
cl_event(SCR * sp,EVENT * evp,u_int32_t flags,int ms)58 cl_event(SCR *sp, EVENT *evp, u_int32_t flags, int ms)
59 {
60 	struct timeval t, *tp;
61 	CL_PRIVATE *clp;
62 	size_t lines, columns;
63 	int changed, nr = 0;
64 	const CHAR_T *wp;
65 	size_t wlen;
66 	int rc;
67 
68 	/*
69 	 * Queue signal based events.  We never clear SIGHUP or SIGTERM events,
70 	 * so that we just keep returning them until the editor dies.
71 	 */
72 	clp = CLP(sp);
73 retest:	if (LF_ISSET(EC_INTERRUPT) || F_ISSET(clp, CL_SIGINT)) {
74 		if (F_ISSET(clp, CL_SIGINT)) {
75 			F_CLR(clp, CL_SIGINT);
76 			evp->e_event = E_INTERRUPT;
77 		} else
78 			evp->e_event = E_TIMEOUT;
79 		return (0);
80 	}
81 	if (F_ISSET(clp, CL_SIGHUP | CL_SIGTERM | CL_SIGWINCH)) {
82 		if (F_ISSET(clp, CL_SIGHUP)) {
83 			evp->e_event = E_SIGHUP;
84 			return (0);
85 		}
86 		if (F_ISSET(clp, CL_SIGTERM)) {
87 			evp->e_event = E_SIGTERM;
88 			return (0);
89 		}
90 		if (F_ISSET(clp, CL_SIGWINCH)) {
91 			F_CLR(clp, CL_SIGWINCH);
92 			if (cl_ssize(sp, 1, &lines, &columns, &changed))
93 				return (1);
94 			if (changed) {
95 				(void)cl_resize(sp, lines, columns);
96 				evp->e_event = E_WRESIZE;
97 				return (0);
98 			}
99 			/* No real change, ignore the signal. */
100 		}
101 	}
102 
103 	/* Set timer. */
104 	if (ms == 0)
105 		tp = NULL;
106 	else {
107 		t.tv_sec = ms / 1000;
108 		t.tv_usec = (ms % 1000) * 1000;
109 		tp = &t;
110 	}
111 
112 	/* Read input characters. */
113 read:
114 	switch (cl_read(sp, LF_ISSET(EC_QUOTED | EC_RAW),
115 	    clp->ibuf + clp->skip, SIZE(clp->ibuf) - clp->skip, &nr, tp)) {
116 	case INP_OK:
117 		rc = INPUT2INT5(sp, clp->cw, clp->ibuf, nr + clp->skip,
118 				wp, wlen);
119 		evp->e_csp = __UNCONST(wp);
120 		evp->e_len = wlen;
121 		evp->e_event = E_STRING;
122 		if (rc < 0) {
123 		    int n = -rc;
124 		    memmove(clp->ibuf, clp->ibuf + nr + clp->skip - n, n);
125 		    clp->skip = n;
126 		    if (wlen == 0)
127 			goto read;
128 		} else if (rc == 0)
129 		    clp->skip = 0;
130 		else
131 		    msgq(sp, M_ERR, "323|Invalid input. Truncated.");
132 		break;
133 	case INP_ERR:
134 		evp->e_event = E_ERR;
135 		break;
136 	case INP_EOF:
137 		evp->e_event = E_EOF;
138 		break;
139 	case INP_INTR:
140 		goto retest;
141 	case INP_TIMEOUT:
142 		evp->e_event = E_TIMEOUT;
143 		break;
144 	default:
145 		abort();
146 	}
147 	return (0);
148 }
149 
150 /*
151  * cl_read --
152  *	Read characters from the input.
153  */
154 static input_t
cl_read(SCR * sp,u_int32_t flags,char * bp,size_t blen,int * nrp,struct timeval * tp)155 cl_read(SCR *sp, u_int32_t flags, char *bp, size_t blen, int *nrp, struct timeval *tp)
156 {
157 	struct termios term1, term2;
158 	struct timeval poll;
159 	CL_PRIVATE *clp;
160 	GS *gp;
161 	fd_set rdfd;
162 	input_t rval;
163 	int maxfd, nr, term_reset;
164 
165 	gp = sp->gp;
166 	clp = CLP(sp);
167 	term_reset = 0;
168 
169 	/*
170 	 * 1: A read from a file or a pipe.  In this case, the reads
171 	 *    never timeout regardless.  This means that we can hang
172 	 *    when trying to complete a map, but we're going to hang
173 	 *    on the next read anyway.
174 	 */
175 	if (!F_ISSET(clp, CL_STDIN_TTY)) {
176 		switch (nr = read(STDIN_FILENO, bp, blen)) {
177 		case 0:
178 			return (INP_EOF);
179 		case -1:
180 			goto err;
181 		default:
182 			*nrp = nr;
183 			return (INP_OK);
184 		}
185 		/* NOTREACHED */
186 	}
187 
188 	/*
189 	 * 2: A read with an associated timeout, e.g., trying to complete
190 	 *    a map sequence.  If input exists, we fall into #3.
191 	 */
192 	FD_ZERO(&rdfd);
193 	poll.tv_sec = 0;
194 	poll.tv_usec = 0;
195 	if (tp != NULL) {
196 		FD_SET(STDIN_FILENO, &rdfd);
197 		switch (select(STDIN_FILENO + 1,
198 		    &rdfd, NULL, NULL, tp == NULL ? &poll : tp)) {
199 		case 0:
200 			return (INP_TIMEOUT);
201 		case -1:
202 			goto err;
203 		default:
204 			break;
205 		}
206 	}
207 
208 	/*
209 	 * The user can enter a key in the editor to quote a character.  If we
210 	 * get here and the next key is supposed to be quoted, do what we can.
211 	 * Reset the tty so that the user can enter a ^C, ^Q, ^S.  There's an
212 	 * obvious race here, when the key has already been entered, but there's
213 	 * nothing that we can do to fix that problem.
214 	 *
215 	 * The editor can ask for the next literal character even thought it's
216 	 * generally running in line-at-a-time mode.  Do what we can.
217 	 */
218 	if (LF_ISSET(EC_QUOTED | EC_RAW) && !tcgetattr(STDIN_FILENO, &term1)) {
219 		term_reset = 1;
220 		if (LF_ISSET(EC_QUOTED)) {
221 			term2 = term1;
222 			term2.c_lflag &= ~ISIG;
223 			term2.c_iflag &= ~(IXON | IXOFF);
224 			(void)tcsetattr(STDIN_FILENO,
225 			    TCSASOFT | TCSADRAIN, &term2);
226 		} else
227 			(void)tcsetattr(STDIN_FILENO,
228 			    TCSASOFT | TCSADRAIN, &clp->vi_enter);
229 	}
230 
231 	/*
232 	 * 3: Wait for input.
233 	 *
234 	 * Select on the command input and scripting window file descriptors.
235 	 * It's ugly that we wait on scripting file descriptors here, but it's
236 	 * the only way to keep from locking out scripting windows.
237 	 */
238 	if (F_ISSET(gp, G_SCRWIN)) {
239 		FD_ZERO(&rdfd);
240 		FD_SET(STDIN_FILENO, &rdfd);
241 		maxfd = STDIN_FILENO;
242 		if (sscr_check_input(sp, &rdfd, maxfd))
243 			goto err;
244 	}
245 
246 	/*
247 	 * 4: Read the input.
248 	 *
249 	 * !!!
250 	 * What's going on here is some scary stuff.  Ex runs the terminal in
251 	 * canonical mode.  So, the <newline> character terminating a line of
252 	 * input is returned in the buffer, but a trailing <EOF> character is
253 	 * not similarly included.  As ex uses 0<EOF> and ^<EOF> as autoindent
254 	 * commands, it has to see the trailing <EOF> characters to determine
255 	 * the difference between the user entering "0ab" and "0<EOF>ab".  We
256 	 * leave an extra slot in the buffer, so that we can add a trailing
257 	 * <EOF> character if the buffer isn't terminated by a <newline>.  We
258 	 * lose if the buffer is too small for the line and exactly N characters
259 	 * are entered followed by an <EOF> character.
260 	 */
261 #define	ONE_FOR_EOF	1
262 	switch (nr = read(STDIN_FILENO, bp, blen - ONE_FOR_EOF)) {
263 	case  0:				/* EOF. */
264 		/*
265 		 * ^D in canonical mode returns a read of 0, i.e. EOF.  EOF is
266 		 * a valid command, but we don't want to loop forever because
267 		 * the terminal driver is returning EOF because the user has
268 		 * disconnected. The editor will almost certainly try to write
269 		 * something before this fires, which should kill us, but You
270 		 * Never Know.
271 		 */
272 		if (++clp->eof_count < 50) {
273 			bp[0] = clp->orig.c_cc[VEOF];
274 			*nrp = 1;
275 			rval = INP_OK;
276 
277 		} else
278 			rval = INP_EOF;
279 		break;
280 	case -1:				/* Error or interrupt. */
281 err:		if (errno == EINTR)
282 			rval = INP_INTR;
283 		else {
284 			rval = INP_ERR;
285 			msgq(sp, M_SYSERR, "input");
286 		}
287 		break;
288 	default:				/* Input characters. */
289 		if (F_ISSET(sp, SC_EX) && bp[nr - 1] != '\n')
290 			bp[nr++] = clp->orig.c_cc[VEOF];
291 		*nrp = nr;
292 		clp->eof_count = 0;
293 		rval = INP_OK;
294 		break;
295 	}
296 
297 	/* Restore the terminal state if it was modified. */
298 	if (term_reset)
299 		(void)tcsetattr(STDIN_FILENO, TCSASOFT | TCSADRAIN, &term1);
300 	return (rval);
301 }
302 
303 /*
304  * cl_resize --
305  *	Reset the options for a resize event.
306  */
307 static int
cl_resize(SCR * sp,size_t lines,size_t columns)308 cl_resize(SCR *sp, size_t lines, size_t columns)
309 {
310 	int rval;
311 
312 	rval = api_opts_set(sp, L("lines"), NULL, lines, 0);
313 	if (api_opts_set(sp, L("columns"), NULL, columns, 0))
314 		rval = 1;
315 	return (rval);
316 }
317