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/proc.h>
  21 #include <sys/sysctl.h>
  22 #include <sys/stat.h>
  23
  24 #include <errno.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <unistd.h>
  28
  29 #ifndef nitems
  30 #define nitems(_a) (sizeof((_a)) / sizeof((_a)[0]))
  31 #endif
  32
  33 #define is_runnable(p) \
  34         ((p)->p_stat == SRUN || (p)->p_stat == SIDL || (p)->p_stat == SONPROC)
  35 #define is_stopped(p) \
  36         ((p)->p_stat == SSTOP || (p)->p_stat == SZOMB || (p)->p_stat == SDEAD)
  37
  38 struct kinfo_proc       *cmp_procs(struct kinfo_proc *, struct kinfo_proc *);
  39 char                    *get_proc_name(int, char *);
  40 char                    *get_proc_cwd(int);
  41
  42 struct kinfo_proc *
  43 cmp_procs(struct kinfo_proc *p1, struct kinfo_proc *p2)
  44 {
  45         if (is_runnable(p1) && !is_runnable(p2))
  46                 return (p1);
  47         if (!is_runnable(p1) && is_runnable(p2))
  48                 return (p2);
  49
  50         if (is_stopped(p1) && !is_stopped(p2))
  51                 return (p1);
  52         if (!is_stopped(p1) && is_stopped(p2))
  53                 return (p2);
  54
  55         if (p1->p_estcpu > p2->p_estcpu)
  56                 return (p1);
  57         if (p1->p_estcpu < p2->p_estcpu)
  58                 return (p2);
  59
  60         if (p1->p_slptime < p2->p_slptime)
  61                 return (p1);
  62         if (p1->p_slptime > p2->p_slptime)
  63                 return (p2);
  64
  65         if ((p1->p_flag & P_SINTR) && !(p2->p_flag & P_SINTR))
  66                 return (p1);
  67         if (!(p1->p_flag & P_SINTR) && (p2->p_flag & P_SINTR))
  68                 return (p2);
  69
  70         if (strcmp(p1->p_comm, p2->p_comm) < 0)
  71                 return (p1);
  72         if (strcmp(p1->p_comm, p2->p_comm) > 0)
  73                 return (p2);
  74
  75         if (p1->p_pid > p2->p_pid)
  76                 return (p1);
  77         return (p2);
  78 }
  79
  80 char *
  81 get_proc_name(int fd, char *tty)
  82 {
  83         int              mib[6] = { CTL_KERN, KERN_PROC, KERN_PROC_PGRP, 0,
  84                                     sizeof(struct kinfo_proc), 0 };
  85         struct stat      sb;
  86         size_t           len;
  87         struct kinfo_proc *buf, *newbuf, *bestp;
  88         u_int            i;
  89         char            *name;
  90
  91         buf = NULL;
  92
  93         if (stat(tty, &sb) == -1)
  94                 return (NULL);
  95         if ((mib[3] = tcgetpgrp(fd)) == -1)
  96                 return (NULL);
  97
  98 retry:
  99         if (sysctl(mib, nitems(mib), NULL, &len, NULL, 0) == -1)
 100                 return (NULL);
 101         len = (len * 5) / 4;
 102
 103         if ((newbuf = realloc(buf, len)) == NULL)
 104                 goto error;
 105         buf = newbuf;
 106
 107         mib[5] = (int)(len / sizeof(struct kinfo_proc));
 108         if (sysctl(mib, nitems(mib), buf, &len, NULL, 0) == -1) {
 109                 if (errno == ENOMEM)
 110                         goto retry;
 111                 goto error;
 112         }
 113
 114         bestp = NULL;
 115         for (i = 0; i < len / sizeof (struct kinfo_proc); i++) {
 116                 if ((dev_t)buf[i].p_tdev != sb.st_rdev)
 117                         continue;
 118                 if (bestp == NULL)
 119                         bestp = &buf[i];
 120                 else
 121                         bestp = cmp_procs(&buf[i], bestp);
 122         }
 123
 124         name = NULL;
 125         if (bestp != NULL)
 126                 name = strdup(bestp->p_comm);
 127
 128         free(buf);
 129         return (name);
 130
 131 error:
 132         free(buf);
 133         return (NULL);
 134 }
 135
 136 char*
 137 get_proc_cwd(int fd)
 138 {
 139         int             name[] = { CTL_KERN, KERN_PROC_CWD, 0 };
 140         static char     path[MAXPATHLEN];
 141         size_t          pathlen = sizeof path;
 142
 143         if ((name[2] = tcgetpgrp(fd)) == -1)
 144                 return (NULL);
 145         if (sysctl(name, 3, path, &pathlen, NULL, 0) != 0)
 146                 return (NULL);
 147         return (path);
 148 }