osdep-freebsd.c revision 1.1.1.8 
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 <event.h>
28#include <stdint.h>
29#include <stdlib.h>
30#include <string.h>
31#include <unistd.h>
32#include <libutil.h>
33
34#include "compat.h"
35
36struct kinfo_proc	*cmp_procs(struct kinfo_proc *, struct kinfo_proc *);
37char			*osdep_get_name(int, char *);
38char			*osdep_get_cwd(int);
39struct event_base	*osdep_event_init(void);
40
41#ifndef nitems
42#define nitems(_a) (sizeof((_a)) / sizeof((_a)[0]))
43#endif
44
45#define is_runnable(p) \
46	((p)->ki_stat == SRUN || (p)->ki_stat == SIDL)
47#define is_stopped(p) \
48	((p)->ki_stat == SSTOP || (p)->ki_stat == SZOMB)
49
50struct kinfo_proc *
51cmp_procs(struct kinfo_proc *p1, struct kinfo_proc *p2)
52{
53	if (is_runnable(p1) && !is_runnable(p2))
54		return (p1);
55	if (!is_runnable(p1) && is_runnable(p2))
56		return (p2);
57
58	if (is_stopped(p1) && !is_stopped(p2))
59		return (p1);
60	if (!is_stopped(p1) && is_stopped(p2))
61		return (p2);
62
63	if (p1->ki_estcpu > p2->ki_estcpu)
64		return (p1);
65	if (p1->ki_estcpu < p2->ki_estcpu)
66		return (p2);
67
68	if (p1->ki_slptime < p2->ki_slptime)
69		return (p1);
70	if (p1->ki_slptime > p2->ki_slptime)
71		return (p2);
72
73	if (strcmp(p1->ki_comm, p2->ki_comm) < 0)
74		return (p1);
75	if (strcmp(p1->ki_comm, p2->ki_comm) > 0)
76		return (p2);
77
78	if (p1->ki_pid > p2->ki_pid)
79		return (p1);
80	return (p2);
81}
82
83char *
84osdep_get_name(int fd, char *tty)
85{
86	int		 mib[4] = { CTL_KERN, KERN_PROC, KERN_PROC_PGRP, 0 };
87	struct stat	 sb;
88	size_t		 len;
89	struct kinfo_proc *buf, *newbuf, *bestp;
90	u_int		 i;
91	char		*name;
92
93	buf = NULL;
94
95	if (stat(tty, &sb) == -1)
96		return (NULL);
97	if ((mib[3] = tcgetpgrp(fd)) == -1)
98		return (NULL);
99
100retry:
101	if (sysctl(mib, nitems(mib), NULL, &len, NULL, 0) == -1)
102		return (NULL);
103	len = (len * 5) / 4;
104
105	if ((newbuf = realloc(buf, len)) == NULL)
106		goto error;
107	buf = newbuf;
108
109	if (sysctl(mib, nitems(mib), buf, &len, NULL, 0) == -1) {
110		if (errno == ENOMEM)
111			goto retry;
112		goto error;
113	}
114
115	bestp = NULL;
116	for (i = 0; i < len / sizeof (struct kinfo_proc); i++) {
117		if (buf[i].ki_tdev != sb.st_rdev)
118			continue;
119		if (bestp == NULL)
120			bestp = &buf[i];
121		else
122			bestp = cmp_procs(&buf[i], bestp);
123	}
124
125	name = NULL;
126	if (bestp != NULL)
127		name = strdup(bestp->ki_comm);
128
129	free(buf);
130	return (name);
131
132error:
133	free(buf);
134	return (NULL);
135}
136
137static char *
138osdep_get_cwd_fallback(int fd)
139{
140	static char		 wd[PATH_MAX];
141	struct kinfo_file	*info = NULL;
142	pid_t			 pgrp;
143	int			 nrecords, i;
144
145	if ((pgrp = tcgetpgrp(fd)) == -1)
146		return (NULL);
147
148	if ((info = kinfo_getfile(pgrp, &nrecords)) == NULL)
149		return (NULL);
150
151	for (i = 0; i < nrecords; i++) {
152		if (info[i].kf_fd == KF_FD_TYPE_CWD) {
153			strlcpy(wd, info[i].kf_path, sizeof wd);
154			free(info);
155			return (wd);
156		}
157	}
158
159	free(info);
160	return (NULL);
161}
162
163#ifdef KERN_PROC_CWD
164char *
165osdep_get_cwd(int fd)
166{
167	static struct kinfo_file	info;
168	static int			fallback;
169	int	name[] = { CTL_KERN, KERN_PROC, KERN_PROC_CWD, 0 };
170	size_t	len = sizeof info;
171
172	if (fallback)
173		return (osdep_get_cwd_fallback(fd));
174
175	if ((name[3] = tcgetpgrp(fd)) == -1)
176		return (NULL);
177
178	if (sysctl(name, 4, &info, &len, NULL, 0) == -1) {
179		if (errno == ENOENT) {
180			fallback = 1;
181			return (osdep_get_cwd_fallback(fd));
182		}
183		return (NULL);
184	}
185	return (info.kf_path);
186}
187#else /* !KERN_PROC_CWD */
188char *
189osdep_get_cwd(int fd)
190{
191	return (osdep_get_cwd_fallback(fd));
192}
193#endif /* KERN_PROC_CWD */
194
195struct event_base *
196osdep_event_init(void)
197{
198	struct event_base	*base;
199
200	/*
201	 * On some versions of FreeBSD, kqueue doesn't work properly on tty
202	 * file descriptors. This is fixed in recent FreeBSD versions.
203	 */
204	setenv("EVENT_NOKQUEUE", "1", 1);
205
206	base = event_init();
207	unsetenv("EVENT_NOKQUEUE");
208	return (base);
209}
210