osdep-freebsd.c revision 1.1.1.7 
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
34struct kinfo_proc	*cmp_procs(struct kinfo_proc *, struct kinfo_proc *);
35char			*osdep_get_name(int, char *);
36char			*osdep_get_cwd(int);
37struct event_base	*osdep_event_init(void);
38
39#ifndef nitems
40#define nitems(_a) (sizeof((_a)) / sizeof((_a)[0]))
41#endif
42
43#define is_runnable(p) \
44	((p)->ki_stat == SRUN || (p)->ki_stat == SIDL)
45#define is_stopped(p) \
46	((p)->ki_stat == SSTOP || (p)->ki_stat == SZOMB)
47
48struct kinfo_proc *
49cmp_procs(struct kinfo_proc *p1, struct kinfo_proc *p2)
50{
51	if (is_runnable(p1) && !is_runnable(p2))
52		return (p1);
53	if (!is_runnable(p1) && is_runnable(p2))
54		return (p2);
55
56	if (is_stopped(p1) && !is_stopped(p2))
57		return (p1);
58	if (!is_stopped(p1) && is_stopped(p2))
59		return (p2);
60
61	if (p1->ki_estcpu > p2->ki_estcpu)
62		return (p1);
63	if (p1->ki_estcpu < p2->ki_estcpu)
64		return (p2);
65
66	if (p1->ki_slptime < p2->ki_slptime)
67		return (p1);
68	if (p1->ki_slptime > p2->ki_slptime)
69		return (p2);
70
71	if (strcmp(p1->ki_comm, p2->ki_comm) < 0)
72		return (p1);
73	if (strcmp(p1->ki_comm, p2->ki_comm) > 0)
74		return (p2);
75
76	if (p1->ki_pid > p2->ki_pid)
77		return (p1);
78	return (p2);
79}
80
81char *
82osdep_get_name(int fd, char *tty)
83{
84	int		 mib[4] = { CTL_KERN, KERN_PROC, KERN_PROC_PGRP, 0 };
85	struct stat	 sb;
86	size_t		 len;
87	struct kinfo_proc *buf, *newbuf, *bestp;
88	u_int		 i;
89	char		*name;
90
91	buf = NULL;
92
93	if (stat(tty, &sb) == -1)
94		return (NULL);
95	if ((mib[3] = tcgetpgrp(fd)) == -1)
96		return (NULL);
97
98retry:
99	if (sysctl(mib, nitems(mib), NULL, &len, NULL, 0) == -1)
100		return (NULL);
101	len = (len * 5) / 4;
102
103	if ((newbuf = realloc(buf, len)) == NULL)
104		goto error;
105	buf = newbuf;
106
107	if (sysctl(mib, nitems(mib), buf, &len, NULL, 0) == -1) {
108		if (errno == ENOMEM)
109			goto retry;
110		goto error;
111	}
112
113	bestp = NULL;
114	for (i = 0; i < len / sizeof (struct kinfo_proc); i++) {
115		if (buf[i].ki_tdev != sb.st_rdev)
116			continue;
117		if (bestp == NULL)
118			bestp = &buf[i];
119		else
120			bestp = cmp_procs(&buf[i], bestp);
121	}
122
123	name = NULL;
124	if (bestp != NULL)
125		name = strdup(bestp->ki_comm);
126
127	free(buf);
128	return (name);
129
130error:
131	free(buf);
132	return (NULL);
133}
134
135static char *
136osdep_get_cwd_fallback(int fd)
137{
138	static char		 wd[PATH_MAX];
139	struct kinfo_file	*info = NULL;
140	pid_t			 pgrp;
141	int			 nrecords, i;
142
143	if ((pgrp = tcgetpgrp(fd)) == -1)
144		return (NULL);
145
146	if ((info = kinfo_getfile(pgrp, &nrecords)) == NULL)
147		return (NULL);
148
149	for (i = 0; i < nrecords; i++) {
150		if (info[i].kf_fd == KF_FD_TYPE_CWD) {
151			strlcpy(wd, info[i].kf_path, sizeof wd);
152			free(info);
153			return (wd);
154		}
155	}
156
157	free(info);
158	return (NULL);
159}
160
161#ifdef KERN_PROC_CWD
162char *
163osdep_get_cwd(int fd)
164{
165	static struct kinfo_file	info;
166	static int			fallback;
167	int	name[] = { CTL_KERN, KERN_PROC, KERN_PROC_CWD, 0 };
168	size_t	len = sizeof info;
169
170	if (fallback)
171		return (osdep_get_cwd_fallback(fd));
172
173	if ((name[3] = tcgetpgrp(fd)) == -1)
174		return (NULL);
175
176	if (sysctl(name, 4, &info, &len, NULL, 0) == -1) {
177		if (errno == ENOENT) {
178			fallback = 1;
179			return (osdep_get_cwd_fallback(fd));
180		}
181		return (NULL);
182	}
183	return (info.kf_path);
184}
185#else /* !KERN_PROC_CWD */
186char *
187osdep_get_cwd(int fd)
188{
189	return (osdep_get_cwd_fallback(fd));
190}
191#endif /* KERN_PROC_CWD */
192
193struct event_base *
194osdep_event_init(void)
195{
196	struct event_base	*base;
197
198	/*
199	 * On some versions of FreeBSD, kqueue doesn't work properly on tty
200	 * file descriptors. This is fixed in recent FreeBSD versions.
201	 */
202	setenv("EVENT_NOKQUEUE", "1", 1);
203
204	base = event_init();
205	unsetenv("EVENT_NOKQUEUE");
206	return (base);
207}
208