1/*
2 * Copyright (c) 1993, 1994, 1995, 1996 Rick Sladkey <jrs@world.std.com>
3 * Copyright (c) 1996-1999 Wichert Akkerman <wichert@cistron.nl>
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 * 3. The name of the author may not be used to endorse or promote products
15 *    derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29#include "defs.h"
30#include <poll.h>
31
32#include "xlat/pollflags.h"
33
34static bool
35print_pollfd(struct tcb *tcp, void *elem_buf, size_t elem_size, void *data)
36{
37	const struct pollfd *fds = elem_buf;
38
39	tprints("{fd=");
40	printfd(tcp, fds->fd);
41	if (fds->fd >= 0) {
42		tprints(", events=");
43		printflags(pollflags, (unsigned short) fds->events, "POLL???");
44	}
45	tprints("}");
46
47	return true;
48}
49
50static void
51decode_poll_entering(struct tcb *tcp)
52{
53	const kernel_ulong_t addr = tcp->u_arg[0];
54	const unsigned int nfds = tcp->u_arg[1];
55	struct pollfd fds;
56
57	print_array(tcp, addr, nfds, &fds, sizeof(fds),
58		    umoven_or_printaddr, print_pollfd, 0);
59	tprintf(", %u, ", nfds);
60}
61
62static int
63decode_poll_exiting(struct tcb *const tcp, const kernel_ulong_t pts)
64{
65	struct pollfd fds;
66	const unsigned int nfds = tcp->u_arg[1];
67	const unsigned long size = sizeof(fds) * nfds;
68	const kernel_ulong_t start = tcp->u_arg[0];
69	const kernel_ulong_t end = start + size;
70	kernel_ulong_t cur;
71	const unsigned int max_printed =
72		abbrev(tcp) ? max_strlen : -1U;
73	unsigned int printed;
74
75	static char outstr[1024];
76	char *outptr;
77#define end_outstr (outstr + sizeof(outstr))
78
79	if (syserror(tcp))
80		return 0;
81	if (tcp->u_rval == 0) {
82		tcp->auxstr = "Timeout";
83		return RVAL_STR;
84	}
85
86	if (!verbose(tcp) || !start || !nfds ||
87	    size / sizeof(fds) != nfds || end < start)
88		return 0;
89
90	outptr = outstr;
91
92	for (printed = 0, cur = start; cur < end; cur += sizeof(fds)) {
93		if (umove(tcp, cur, &fds) < 0) {
94			if (outptr == outstr)
95				*outptr++ = '[';
96			else
97				outptr = stpcpy(outptr, ", ");
98			outptr += sprintf(outptr, "%#" PRI_klx, cur);
99			break;
100		}
101		if (!fds.revents)
102			continue;
103		if (outptr == outstr)
104			*outptr++ = '[';
105		else
106			outptr = stpcpy(outptr, ", ");
107		if (printed >= max_printed) {
108			outptr = stpcpy(outptr, "...");
109			break;
110		}
111
112		static const char fmt[] = "{fd=%d, revents=";
113		char fdstr[sizeof(fmt) + sizeof(int) * 3];
114		sprintf(fdstr, fmt, fds.fd);
115
116		const char *flagstr = sprintflags("", pollflags,
117						  (unsigned short) fds.revents);
118
119		if (outptr + strlen(fdstr) + strlen(flagstr) + 1 >=
120		    end_outstr - (2 + 2 * sizeof(long) + sizeof(", ], ..."))) {
121			outptr = stpcpy(outptr, "...");
122			break;
123		}
124		outptr = stpcpy(outptr, fdstr);
125		outptr = stpcpy(outptr, flagstr);
126		*outptr++ = '}';
127		++printed;
128	}
129
130	if (outptr != outstr)
131		*outptr++ = ']';
132
133	*outptr = '\0';
134	if (pts) {
135		const char *str = sprint_timespec(tcp, pts);
136
137		if (outptr + sizeof(", left ") + strlen(str) < end_outstr) {
138			outptr = stpcpy(outptr, outptr == outstr ? "left " : ", left ");
139			outptr = stpcpy(outptr, str);
140		} else {
141			outptr = stpcpy(outptr, ", ...");
142		}
143	}
144
145	if (outptr == outstr)
146		return 0;
147
148	tcp->auxstr = outstr;
149	return RVAL_STR;
150#undef end_outstr
151}
152
153SYS_FUNC(poll)
154{
155	if (entering(tcp)) {
156		decode_poll_entering(tcp);
157		int timeout = tcp->u_arg[2];
158
159#ifdef INFTIM
160		if (INFTIM == timeout)
161			tprints("INFTIM");
162		else
163#endif
164			tprintf("%d", timeout);
165
166		return 0;
167	} else {
168		return decode_poll_exiting(tcp, 0);
169	}
170}
171
172SYS_FUNC(ppoll)
173{
174	if (entering(tcp)) {
175		decode_poll_entering(tcp);
176
177		print_timespec(tcp, tcp->u_arg[2]);
178		tprints(", ");
179		/* NB: kernel requires arg[4] == NSIG_BYTES */
180		print_sigset_addr_len(tcp, tcp->u_arg[3], tcp->u_arg[4]);
181		tprintf(", %" PRI_klu, tcp->u_arg[4]);
182
183		return 0;
184	} else {
185		return decode_poll_exiting(tcp, tcp->u_arg[2]);
186	}
187}
188