procname.c revision 1.8 
1/* $OpenBSD: procname.c,v 1.8 2011/12/09 16:28:18 nicm 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/sysctl.h>
21#include <sys/stat.h>
22
23#include <errno.h>
24#include <stdlib.h>
25#include <string.h>
26#include <unistd.h>
27
28#ifndef nitems
29#define nitems(_a) (sizeof((_a)) / sizeof((_a)[0]))
30#endif
31
32#define is_runnable(p) \
33	((p)->p_stat == SRUN || (p)->p_stat == SIDL || (p)->p_stat == SONPROC)
34#define is_stopped(p) \
35	((p)->p_stat == SSTOP || (p)->p_stat == SZOMB || (p)->p_stat == SDEAD)
36
37struct kinfo_proc	*cmp_procs(struct kinfo_proc *, struct kinfo_proc *);
38char			*get_proc_name(int, char *);
39char			*get_proc_cwd(pid_t);
40
41struct kinfo_proc *
42cmp_procs(struct kinfo_proc *p1, struct kinfo_proc *p2)
43{
44	if (is_runnable(p1) && !is_runnable(p2))
45		return (p1);
46	if (!is_runnable(p1) && is_runnable(p2))
47		return (p2);
48
49	if (is_stopped(p1) && !is_stopped(p2))
50		return (p1);
51	if (!is_stopped(p1) && is_stopped(p2))
52		return (p2);
53
54	if (p1->p_estcpu > p2->p_estcpu)
55		return (p1);
56	if (p1->p_estcpu < p2->p_estcpu)
57		return (p2);
58
59	if (p1->p_slptime < p2->p_slptime)
60		return (p1);
61	if (p1->p_slptime > p2->p_slptime)
62		return (p2);
63
64	if ((p1->p_flag & P_SINTR) && !(p2->p_flag & P_SINTR))
65		return (p1);
66	if (!(p1->p_flag & P_SINTR) && (p2->p_flag & P_SINTR))
67		return (p2);
68
69	if (strcmp(p1->p_comm, p2->p_comm) < 0)
70		return (p1);
71	if (strcmp(p1->p_comm, p2->p_comm) > 0)
72		return (p2);
73
74	if (p1->p_pid > p2->p_pid)
75		return (p1);
76	return (p2);
77}
78
79char *
80get_proc_name(int fd, char *tty)
81{
82	int		 mib[6] = { CTL_KERN, KERN_PROC, KERN_PROC_PGRP, 0,
83				    sizeof(struct kinfo_proc), 0 };
84	struct stat	 sb;
85	size_t		 len;
86	struct kinfo_proc *buf, *newbuf, *bestp;
87	u_int		 i;
88	char		*name;
89
90	buf = NULL;
91
92	if (stat(tty, &sb) == -1)
93		return (NULL);
94	if ((mib[3] = tcgetpgrp(fd)) == -1)
95		return (NULL);
96
97retry:
98	if (sysctl(mib, nitems(mib), NULL, &len, NULL, 0) == -1)
99		return (NULL);
100	len = (len * 5) / 4;
101
102	if ((newbuf = realloc(buf, len)) == NULL)
103		goto error;
104	buf = newbuf;
105
106	mib[5] = (int)(len / sizeof(struct kinfo_proc));
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 ((dev_t)buf[i].p_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->p_comm);
126
127	free(buf);
128	return (name);
129
130error:
131	free(buf);
132	return (NULL);
133}
134
135char*
136get_proc_cwd(pid_t pid)
137{
138	int		name[] = { CTL_KERN, KERN_PROC_CWD, (int)pid };
139	static char	path[MAXPATHLEN];
140	size_t		pathlen = sizeof path;
141
142	if (sysctl(name, 3, path, &pathlen, NULL, 0) != 0)
143		return (NULL);
144	return (path);
145}
146