osdep-freebsd.c revision 1.1.1.9 
1/* $OpenBSD$ */
2
3/*
4 * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
15 * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
16 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18
19#include <sys/param.h>
20#include <sys/proc.h>
21#include <sys/stat.h>
22#include <sys/sysctl.h>
23#include <sys/user.h>
24
25#include <err.h>
26#include <errno.h>
27#include <stdint.h>
28#include <stdlib.h>
29#include <string.h>
30#include <unistd.h>
31#include <libutil.h>
32
33#include "compat.h"
34
35struct kinfo_proc	*cmp_procs(struct kinfo_proc *, struct kinfo_proc *);
36char			*osdep_get_name(int, char *);
37char			*osdep_get_cwd(int);
38struct event_base	*osdep_event_init(void);
39
40#ifndef nitems
41#define nitems(_a) (sizeof((_a)) / sizeof((_a)[0]))
42#endif
43
44#define is_runnable(p) \
45	((p)->ki_stat == SRUN || (p)->ki_stat == SIDL)
46#define is_stopped(p) \
47	((p)->ki_stat == SSTOP || (p)->ki_stat == SZOMB)
48
49struct kinfo_proc *
50cmp_procs(struct kinfo_proc *p1, struct kinfo_proc *p2)
51{
52	if (is_runnable(p1) && !is_runnable(p2))
53		return (p1);
54	if (!is_runnable(p1) && is_runnable(p2))
55		return (p2);
56
57	if (is_stopped(p1) && !is_stopped(p2))
58		return (p1);
59	if (!is_stopped(p1) && is_stopped(p2))
60		return (p2);
61
62	if (p1->ki_estcpu > p2->ki_estcpu)
63		return (p1);
64	if (p1->ki_estcpu < p2->ki_estcpu)
65		return (p2);
66
67	if (p1->ki_slptime < p2->ki_slptime)
68		return (p1);
69	if (p1->ki_slptime > p2->ki_slptime)
70		return (p2);
71
72	if (strcmp(p1->ki_comm, p2->ki_comm) < 0)
73		return (p1);
74	if (strcmp(p1->ki_comm, p2->ki_comm) > 0)
75		return (p2);
76
77	if (p1->ki_pid > p2->ki_pid)
78		return (p1);
79	return (p2);
80}
81
82char *
83osdep_get_name(int fd, char *tty)
84{
85	int		 mib[4] = { CTL_KERN, KERN_PROC, KERN_PROC_PGRP, 0 };
86	struct stat	 sb;
87	size_t		 len;
88	struct kinfo_proc *buf, *newbuf, *bestp;
89	u_int		 i;
90	char		*name;
91
92	buf = NULL;
93
94	if (stat(tty, &sb) == -1)
95		return (NULL);
96	if ((mib[3] = tcgetpgrp(fd)) == -1)
97		return (NULL);
98
99retry:
100	if (sysctl(mib, nitems(mib), NULL, &len, NULL, 0) == -1)
101		return (NULL);
102	len = (len * 5) / 4;
103
104	if ((newbuf = realloc(buf, len)) == NULL)
105		goto error;
106	buf = newbuf;
107
108	if (sysctl(mib, nitems(mib), buf, &len, NULL, 0) == -1) {
109		if (errno == ENOMEM)
110			goto retry;
111		goto error;
112	}
113
114	bestp = NULL;
115	for (i = 0; i < len / sizeof (struct kinfo_proc); i++) {
116		if (buf[i].ki_tdev != sb.st_rdev)
117			continue;
118		if (bestp == NULL)
119			bestp = &buf[i];
120		else
121			bestp = cmp_procs(&buf[i], bestp);
122	}
123
124	name = NULL;
125	if (bestp != NULL)
126		name = strdup(bestp->ki_comm);
127
128	free(buf);
129	return (name);
130
131error:
132	free(buf);
133	return (NULL);
134}
135
136static char *
137osdep_get_cwd_fallback(int fd)
138{
139	static char		 wd[PATH_MAX];
140	struct kinfo_file	*info = NULL;
141	pid_t			 pgrp;
142	int			 nrecords, i;
143
144	if ((pgrp = tcgetpgrp(fd)) == -1)
145		return (NULL);
146
147	if ((info = kinfo_getfile(pgrp, &nrecords)) == NULL)
148		return (NULL);
149
150	for (i = 0; i < nrecords; i++) {
151		if (info[i].kf_fd == KF_FD_TYPE_CWD) {
152			strlcpy(wd, info[i].kf_path, sizeof wd);
153			free(info);
154			return (wd);
155		}
156	}
157
158	free(info);
159	return (NULL);
160}
161
162#ifdef KERN_PROC_CWD
163char *
164osdep_get_cwd(int fd)
165{
166	static struct kinfo_file	info;
167	static int			fallback;
168	int	name[] = { CTL_KERN, KERN_PROC, KERN_PROC_CWD, 0 };
169	size_t	len = sizeof info;
170
171	if (fallback)
172		return (osdep_get_cwd_fallback(fd));
173
174	if ((name[3] = tcgetpgrp(fd)) == -1)
175		return (NULL);
176
177	if (sysctl(name, 4, &info, &len, NULL, 0) == -1) {
178		if (errno == ENOENT) {
179			fallback = 1;
180			return (osdep_get_cwd_fallback(fd));
181		}
182		return (NULL);
183	}
184	return (info.kf_path);
185}
186#else /* !KERN_PROC_CWD */
187char *
188osdep_get_cwd(int fd)
189{
190	return (osdep_get_cwd_fallback(fd));
191}
192#endif /* KERN_PROC_CWD */
193
194struct event_base *
195osdep_event_init(void)
196{
197	struct event_base	*base;
198
199	/*
200	 * On some versions of FreeBSD, kqueue doesn't work properly on tty
201	 * file descriptors. This is fixed in recent FreeBSD versions.
202	 */
203	setenv("EVENT_NOKQUEUE", "1", 1);
204
205	base = event_init();
206	unsetenv("EVENT_NOKQUEUE");
207	return (base);
208}
209