procname.c

   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/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 *
  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 *
  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 *
 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 }