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/param.h>  /* MAXCOMLEN */
  20 #include <sys/types.h>
  21 #include <sys/signal.h>
  22 #include <sys/proc.h>
  23 #include <sys/sysctl.h>
  24 #include <sys/stat.h>
  25
  26 #include <errno.h>
  27 #include <stdlib.h>
  28 #include <string.h>
  29 #include <unistd.h>
  30
  31 #ifndef nitems
  32 #define nitems(_a) (sizeof((_a)) / sizeof((_a)[0]))
  33 #endif
  34
  35 #define is_runnable(p) \
  36         ((p)->p_stat == SRUN || (p)->p_stat == SIDL || (p)->p_stat == SONPROC)
  37 #define is_stopped(p) \
  38         ((p)->p_stat == SSTOP || (p)->p_stat == SDEAD)
  39
  40 static struct kinfo_proc *cmp_procs(struct kinfo_proc *, struct kinfo_proc *);
  41 char    *get_proc_name(int, char *);
  42 char    *get_proc_cwd(int);
  43
  44 static 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->p_estcpu > p2->p_estcpu)
  58                 return (p1);
  59         if (p1->p_estcpu < p2->p_estcpu)
  60                 return (p2);
  61
  62         if (p1->p_slptime < p2->p_slptime)
  63                 return (p1);
  64         if (p1->p_slptime > p2->p_slptime)
  65                 return (p2);
  66
  67         if ((p1->p_flag & P_SINTR) && !(p2->p_flag & P_SINTR))
  68                 return (p1);
  69         if (!(p1->p_flag & P_SINTR) && (p2->p_flag & P_SINTR))
  70                 return (p2);
  71
  72         if (strcmp(p1->p_comm, p2->p_comm) < 0)
  73                 return (p1);
  74         if (strcmp(p1->p_comm, p2->p_comm) > 0)
  75                 return (p2);
  76
  77         if (p1->p_pid > p2->p_pid)
  78                 return (p1);
  79         return (p2);
  80 }
  81
  82 char *
  83 get_proc_name(int fd, char *tty)
  84 {
  85         int              mib[6] = { CTL_KERN, KERN_PROC, KERN_PROC_PGRP, 0,
  86                                     sizeof(struct kinfo_proc), 0 };
  87         struct stat      sb;
  88         size_t           len;
  89         struct kinfo_proc *buf, *newbuf, *bestp;
  90         u_int            i;
  91         char            *name;
  92
  93         buf = NULL;
  94
  95         if (stat(tty, &sb) == -1)
  96                 return (NULL);
  97         if ((mib[3] = tcgetpgrp(fd)) == -1)
  98                 return (NULL);
  99
 100 retry:
 101         if (sysctl(mib, nitems(mib), NULL, &len, NULL, 0) == -1)
 102                 goto error;
 103         len = (len * 5) / 4;
 104
 105         if ((newbuf = realloc(buf, len)) == NULL)
 106                 goto error;
 107         buf = newbuf;
 108
 109         mib[5] = (int)(len / sizeof(struct kinfo_proc));
 110         if (sysctl(mib, nitems(mib), buf, &len, NULL, 0) == -1) {
 111                 if (errno == ENOMEM)
 112                         goto retry;
 113                 goto error;
 114         }
 115
 116         bestp = NULL;
 117         for (i = 0; i < len / sizeof (struct kinfo_proc); i++) {
 118                 if ((dev_t)buf[i].p_tdev != sb.st_rdev)
 119                         continue;
 120                 if (bestp == NULL)
 121                         bestp = &buf[i];
 122                 else
 123                         bestp = cmp_procs(&buf[i], bestp);
 124         }
 125
 126         name = NULL;
 127         if (bestp != NULL)
 128                 name = strdup(bestp->p_comm);
 129
 130         free(buf);
 131         return (name);
 132
 133 error:
 134         free(buf);
 135         return (NULL);
 136 }
 137
 138 char *
 139 get_proc_cwd(int fd)
 140 {
 141         int             name[] = { CTL_KERN, KERN_PROC_CWD, 0 };
 142         static char     path[PATH_MAX];
 143         size_t          pathlen = sizeof path;
 144
 145         if ((name[2] = tcgetpgrp(fd)) == -1)
 146                 return (NULL);
 147         if (sysctl(name, 3, path, &pathlen, NULL, 0) != 0)
 148                 return (NULL);
 149         return (path);
 150 }