procname.c

   1 /* $OpenBSD$ */
   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
  37 struct kinfo_proc       *cmp_procs(struct kinfo_proc *, struct kinfo_proc *);
  38 char                    *get_proc_name(int, char *);
  39 char                    *get_proc_cwd(pid_t);
  40
  41 struct kinfo_proc *
  42 cmp_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
  79 char *
  80 get_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
  97 retry:
  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
 130 error:
 131         free(buf);
 132         return (NULL);
 133 }
 134
 135 char*
 136 get_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 }