xref: /netbsd-src/external/bsd/tmux/dist/osdep-freebsd.c (revision 46f5119e40af2e51998f686b2fdcc76b5488f7f3)
1 /* $Id: osdep-freebsd.c,v 1.1.1.1 2011/03/10 09:15:38 jmmv Exp $ */
2 
3 /*
4  * Copyright (c) 2009 Nicholas Marriott <nicm@users.sourceforge.net>
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 
32 struct kinfo_proc	*cmp_procs(struct kinfo_proc *, struct kinfo_proc *);
33 char			*osdep_get_name(int, char *);
34 
35 #ifndef nitems
36 #define nitems(_a) (sizeof((_a)) / sizeof((_a)[0]))
37 #endif
38 
39 #define is_runnable(p) \
40 	((p)->ki_stat == SRUN || (p)->ki_stat == SIDL)
41 #define is_stopped(p) \
42 	((p)->ki_stat == SSTOP || (p)->ki_stat == SZOMB)
43 
44 struct kinfo_proc *
45 cmp_procs(struct kinfo_proc *p1, struct kinfo_proc *p2)
46 {
47 	if (is_runnable(p1) && !is_runnable(p2))
48 		return (p1);
49 	if (!is_runnable(p1) && is_runnable(p2))
50 		return (p2);
51 
52 	if (is_stopped(p1) && !is_stopped(p2))
53 		return (p1);
54 	if (!is_stopped(p1) && is_stopped(p2))
55 		return (p2);
56 
57 	if (p1->ki_estcpu > p2->ki_estcpu)
58 		return (p1);
59 	if (p1->ki_estcpu < p2->ki_estcpu)
60 		return (p2);
61 
62 	if (p1->ki_slptime < p2->ki_slptime)
63 		return (p1);
64 	if (p1->ki_slptime > p2->ki_slptime)
65 		return (p2);
66 
67 	if (strcmp(p1->ki_comm, p2->ki_comm) < 0)
68 		return (p1);
69 	if (strcmp(p1->ki_comm, p2->ki_comm) > 0)
70 		return (p2);
71 
72 	if (p1->ki_pid > p2->ki_pid)
73 		return (p1);
74 	return (p2);
75 }
76 
77 char *
78 osdep_get_name(int fd, char *tty)
79 {
80 	int		 mib[4] = { CTL_KERN, KERN_PROC, KERN_PROC_PGRP, 0 };
81 	struct stat	 sb;
82 	size_t		 len;
83 	struct kinfo_proc *buf, *newbuf, *bestp;
84 	u_int		 i;
85 	char		*name;
86 
87 	buf = NULL;
88 
89 	if (stat(tty, &sb) == -1)
90 		return (NULL);
91 	if ((mib[3] = tcgetpgrp(fd)) == -1)
92 		return (NULL);
93 
94 retry:
95 	if (sysctl(mib, nitems(mib), NULL, &len, NULL, 0) == -1)
96 		return (NULL);
97 	len = (len * 5) / 4;
98 
99 	if ((newbuf = realloc(buf, len)) == NULL)
100 		goto error;
101 	buf = newbuf;
102 
103 	if (sysctl(mib, nitems(mib), buf, &len, NULL, 0) == -1) {
104 		if (errno == ENOMEM)
105 			goto retry;
106 		goto error;
107 	}
108 
109 	bestp = NULL;
110 	for (i = 0; i < len / sizeof (struct kinfo_proc); i++) {
111 		if (buf[i].ki_tdev != sb.st_rdev)
112 			continue;
113 		if (bestp == NULL)
114 			bestp = &buf[i];
115 		else
116 			bestp = cmp_procs(&buf[i], bestp);
117 	}
118 
119 	name = NULL;
120 	if (bestp != NULL)
121 		name = strdup(bestp->ki_comm);
122 
123 	free(buf);
124 	return (name);
125 
126 error:
127 	free(buf);
128 	return (NULL);
129 }
130