osdep-freebsd.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>
  20 #include <sys/proc.h>
  21 #include <sys/stat.h>
  22 #include <sys/sysctl.h>
  23 #include <sys/user.h>
  24
  25 #include <err.h>
  26 #include <errno.h>
  27 #include <stdint.h>
  28 #include <stdlib.h>
  29 #include <string.h>
  30 #include <unistd.h>
  31 #include <libutil.h>
  32
  33 #include "compat.h"
  34
  35 struct kinfo_proc       *cmp_procs(struct kinfo_proc *, struct kinfo_proc *);
  36 char                    *osdep_get_name(int, char *);
  37 char                    *osdep_get_cwd(int);
  38 struct event_base       *osdep_event_init(void);
  39
  40 #ifndef nitems
  41 #define nitems(_a) (sizeof((_a)) / sizeof((_a)[0]))
  42 #endif
  43
  44 #define is_runnable(p) \
  45         ((p)->ki_stat == SRUN || (p)->ki_stat == SIDL)
  46 #define is_stopped(p) \
  47         ((p)->ki_stat == SSTOP || (p)->ki_stat == SZOMB)
  48
  49 struct kinfo_proc *
  50 cmp_procs(struct kinfo_proc *p1, struct kinfo_proc *p2)
  51 {
  52         if (is_runnable(p1) && !is_runnable(p2))
  53                 return (p1);
  54         if (!is_runnable(p1) && is_runnable(p2))
  55                 return (p2);
  56
  57         if (is_stopped(p1) && !is_stopped(p2))
  58                 return (p1);
  59         if (!is_stopped(p1) && is_stopped(p2))
  60                 return (p2);
  61
  62         if (p1->ki_estcpu > p2->ki_estcpu)
  63                 return (p1);
  64         if (p1->ki_estcpu < p2->ki_estcpu)
  65                 return (p2);
  66
  67         if (p1->ki_slptime < p2->ki_slptime)
  68                 return (p1);
  69         if (p1->ki_slptime > p2->ki_slptime)
  70                 return (p2);
  71
  72         if (strcmp(p1->ki_comm, p2->ki_comm) < 0)
  73                 return (p1);
  74         if (strcmp(p1->ki_comm, p2->ki_comm) > 0)
  75                 return (p2);
  76
  77         if (p1->ki_pid > p2->ki_pid)
  78                 return (p1);
  79         return (p2);
  80 }
  81
  82 char *
  83 osdep_get_name(int fd, char *tty)
  84 {
  85         int              mib[4] = { CTL_KERN, KERN_PROC, KERN_PROC_PGRP, 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                 return (NULL);
 102         len = (len * 5) / 4;
 103
 104         if ((newbuf = realloc(buf, len)) == NULL)
 105                 goto error;
 106         buf = newbuf;
 107
 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 (buf[i].ki_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->ki_comm);
 127
 128         free(buf);
 129         return (name);
 130
 131 error:
 132         free(buf);
 133         return (NULL);
 134 }
 135
 136 static char *
 137 osdep_get_cwd_fallback(int fd)
 138 {
 139         static char              wd[PATH_MAX];
 140         struct kinfo_file       *info = NULL;
 141         pid_t                    pgrp;
 142         int                      nrecords, i;
 143
 144         if ((pgrp = tcgetpgrp(fd)) == -1)
 145                 return (NULL);
 146
 147         if ((info = kinfo_getfile(pgrp, &nrecords)) == NULL)
 148                 return (NULL);
 149
 150         for (i = 0; i < nrecords; i++) {
 151                 if (info[i].kf_fd == KF_FD_TYPE_CWD) {
 152                         strlcpy(wd, info[i].kf_path, sizeof wd);
 153                         free(info);
 154                         return (wd);
 155                 }
 156         }
 157
 158         free(info);
 159         return (NULL);
 160 }
 161
 162 #ifdef KERN_PROC_CWD
 163 char *
 164 osdep_get_cwd(int fd)
 165 {
 166         static struct kinfo_file        info;
 167         static int                      fallback;
 168         int     name[] = { CTL_KERN, KERN_PROC, KERN_PROC_CWD, 0 };
 169         size_t  len = sizeof info;
 170
 171         if (fallback)
 172                 return (osdep_get_cwd_fallback(fd));
 173
 174         if ((name[3] = tcgetpgrp(fd)) == -1)
 175                 return (NULL);
 176
 177         if (sysctl(name, 4, &info, &len, NULL, 0) == -1) {
 178                 if (errno == ENOENT) {
 179                         fallback = 1;
 180                         return (osdep_get_cwd_fallback(fd));
 181                 }
 182                 return (NULL);
 183         }
 184         return (info.kf_path);
 185 }
 186 #else /* !KERN_PROC_CWD */
 187 char *
 188 osdep_get_cwd(int fd)
 189 {
 190         return (osdep_get_cwd_fallback(fd));
 191 }
 192 #endif /* KERN_PROC_CWD */
 193
 194 struct event_base *
 195 osdep_event_init(void)
 196 {
 197         struct event_base       *base;
 198
 199         /*
 200          * On some versions of FreeBSD, kqueue doesn't work properly on tty
 201          * file descriptors. This is fixed in recent FreeBSD versions.
 202          */
 203         setenv("EVENT_NOKQUEUE", "1", 1);
 204
 205         base = event_init();
 206         unsetenv("EVENT_NOKQUEUE");
 207         return (base);
 208 }