xref: /openbsd/usr.bin/tmux/procname.c (revision 4ec73a12)
1 /* $OpenBSD: procname.c,v 1.20 2022/02/22 17:35:01 deraadt Exp $ */
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/types.h>
20 #include <sys/signal.h>
21 #include <sys/proc.h>
22 #include <sys/sysctl.h>
23 #include <sys/stat.h>
24 
25 #include <errno.h>
26 #include <stdlib.h>
27 #include <string.h>
28 #include <unistd.h>
29 
30 #ifndef nitems
31 #define nitems(_a) (sizeof((_a)) / sizeof((_a)[0]))
32 #endif
33 
34 #define is_runnable(p) \
35 	((p)->p_stat == SRUN || (p)->p_stat == SIDL || (p)->p_stat == SONPROC)
36 #define is_stopped(p) \
37 	((p)->p_stat == SSTOP || (p)->p_stat == SDEAD)
38 
39 static struct kinfo_proc *cmp_procs(struct kinfo_proc *, struct kinfo_proc *);
40 char	*get_proc_name(int, char *);
41 char	*get_proc_cwd(int);
42 
43 static struct kinfo_proc *
cmp_procs(struct kinfo_proc * p1,struct kinfo_proc * p2)44 cmp_procs(struct kinfo_proc *p1, struct kinfo_proc *p2)
45 {
46 	if (is_runnable(p1) && !is_runnable(p2))
47 		return (p1);
48 	if (!is_runnable(p1) && is_runnable(p2))
49 		return (p2);
50 
51 	if (is_stopped(p1) && !is_stopped(p2))
52 		return (p1);
53 	if (!is_stopped(p1) && is_stopped(p2))
54 		return (p2);
55 
56 	if (p1->p_estcpu > p2->p_estcpu)
57 		return (p1);
58 	if (p1->p_estcpu < p2->p_estcpu)
59 		return (p2);
60 
61 	if (p1->p_slptime < p2->p_slptime)
62 		return (p1);
63 	if (p1->p_slptime > p2->p_slptime)
64 		return (p2);
65 
66 	if ((p1->p_flag & P_SINTR) && !(p2->p_flag & P_SINTR))
67 		return (p1);
68 	if (!(p1->p_flag & P_SINTR) && (p2->p_flag & P_SINTR))
69 		return (p2);
70 
71 	if (strcmp(p1->p_comm, p2->p_comm) < 0)
72 		return (p1);
73 	if (strcmp(p1->p_comm, p2->p_comm) > 0)
74 		return (p2);
75 
76 	if (p1->p_pid > p2->p_pid)
77 		return (p1);
78 	return (p2);
79 }
80 
81 char *
get_proc_name(int fd,char * tty)82 get_proc_name(int fd, char *tty)
83 {
84 	int		 mib[6] = { CTL_KERN, KERN_PROC, KERN_PROC_PGRP, 0,
85 				    sizeof(struct kinfo_proc), 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 
99 retry:
100 	if (sysctl(mib, nitems(mib), NULL, &len, NULL, 0) == -1)
101 		goto error;
102 	len = (len * 5) / 4;
103 
104 	if ((newbuf = realloc(buf, len)) == NULL)
105 		goto error;
106 	buf = newbuf;
107 
108 	mib[5] = (int)(len / sizeof(struct kinfo_proc));
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 ((dev_t)buf[i].p_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->p_comm);
128 
129 	free(buf);
130 	return (name);
131 
132 error:
133 	free(buf);
134 	return (NULL);
135 }
136 
137 char *
get_proc_cwd(int fd)138 get_proc_cwd(int fd)
139 {
140         int             name[] = { CTL_KERN, KERN_PROC_CWD, 0 };
141         static char     path[PATH_MAX];
142         size_t          pathlen = sizeof path;
143 
144         if ((name[2] = tcgetpgrp(fd)) == -1)
145                 return (NULL);
146         if (sysctl(name, 3, path, &pathlen, NULL, 0) != 0)
147                 return (NULL);
148         return (path);
149 }
150