lib/libkvm/kvm_proc.c

   1 /*-
   2  * Copyright (c) 1989, 1992, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * This code is derived from software developed by the Computer Systems
   6  * Engineering group at Lawrence Berkeley Laboratory under DARPA contract
   7  * BG 91-66 and contributed to Berkeley.
   8  *
   9  * Redistribution and use in source and binary forms, with or without
  10  * modification, are permitted provided that the following conditions
  11  * are met:
  12  * 1. Redistributions of source code must retain the above copyright
  13  *    notice, this list of conditions and the following disclaimer.
  14  * 2. Redistributions in binary form must reproduce the above copyright
  15  *    notice, this list of conditions and the following disclaimer in the
  16  *    documentation and/or other materials provided with the distribution.
  17  * 3. Neither the name of the University nor the names of its contributors
  18  *    may be used to endorse or promote products derived from this software
  19  *    without specific prior written permission.
  20  *
  21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  31  * SUCH DAMAGE.
  32  */
  33
  34 #if 0
  35 #if defined(LIBC_SCCS) && !defined(lint)
  36 static char sccsid[] = "@(#)kvm_proc.c  8.3 (Berkeley) 9/23/93";
  37 #endif /* LIBC_SCCS and not lint */
  38 #endif
  39
  40 #include <sys/cdefs.h>
  41 __FBSDID("$FreeBSD$");
  42
  43 /*
  44  * Proc traversal interface for kvm.  ps and w are (probably) the exclusive
  45  * users of this code, so we've factored it out into a separate module.
  46  * Thus, we keep this grunge out of the other kvm applications (i.e.,
  47  * most other applications are interested only in open/close/read/nlist).
  48  */
  49
  50 #include <sys/param.h>
  51 #define _WANT_UCRED     /* make ucred.h give us 'struct ucred' */
  52 #include <sys/ucred.h>
  53 #include <sys/queue.h>
  54 #include <sys/_lock.h>
  55 #include <sys/_mutex.h>
  56 #include <sys/_task.h>
  57 #include <sys/cpuset.h>
  58 #include <sys/user.h>
  59 #include <sys/proc.h>
  60 #define _WANT_PRISON    /* make jail.h give us 'struct prison' */
  61 #include <sys/jail.h>
  62 #include <sys/exec.h>
  63 #include <sys/stat.h>
  64 #include <sys/sysent.h>
  65 #include <sys/ioctl.h>
  66 #include <sys/tty.h>
  67 #include <sys/file.h>
  68 #include <sys/conf.h>
  69 #define _WANT_KW_EXITCODE
  70 #include <sys/wait.h>
  71 #include <stdio.h>
  72 #include <stdlib.h>
  73 #include <unistd.h>
  74 #include <nlist.h>
  75 #include <kvm.h>
  76
  77 #include <sys/sysctl.h>
  78
  79 #include <limits.h>
  80 #include <memory.h>
  81 #include <paths.h>
  82
  83 #include "kvm_private.h"
  84
  85 #define KREAD(kd, addr, obj) \
  86         (kvm_read(kd, addr, (char *)(obj), sizeof(*obj)) != sizeof(*obj))
  87
  88 static int ticks;
  89 static int hz;
  90 static uint64_t cpu_tick_frequency;
  91
  92 /*
  93  * From sys/kern/kern_tc.c. Depends on cpu_tick_frequency, which is
  94  * read/initialized before this function is ever called.
  95  */
  96 static uint64_t
  97 cputick2usec(uint64_t tick)
  98 {
  99
 100         if (cpu_tick_frequency == 0)
 101                 return (0);
 102         if (tick > 18446744073709551)           /* floor(2^64 / 1000) */
 103                 return (tick / (cpu_tick_frequency / 1000000));
 104         else if (tick > 18446744073709) /* floor(2^64 / 1000000) */
 105                 return ((tick * 1000) / (cpu_tick_frequency / 1000));
 106         else
 107                 return ((tick * 1000000) / cpu_tick_frequency);
 108 }
 109
 110 /*
 111  * Read proc's from memory file into buffer bp, which has space to hold
 112  * at most maxcnt procs.
 113  */
 114 static int
 115 kvm_proclist(kvm_t *kd, int what, int arg, struct proc *p,
 116     struct kinfo_proc *bp, int maxcnt)
 117 {
 118         int cnt = 0;
 119         struct kinfo_proc kinfo_proc, *kp;
 120         struct pgrp pgrp;
 121         struct session sess;
 122         struct cdev t_cdev;
 123         struct tty tty;
 124         struct vmspace vmspace;
 125         struct sigacts sigacts;
 126 #if 0
 127         struct pstats pstats;
 128 #endif
 129         struct ucred ucred;
 130         struct prison pr;
 131         struct thread mtd;
 132         struct proc proc;
 133         struct proc pproc;
 134         struct sysentvec sysent;
 135         char svname[KI_EMULNAMELEN];
 136
 137         kp = &kinfo_proc;
 138         kp->ki_structsize = sizeof(kinfo_proc);
 139         /*
 140          * Loop on the processes. this is completely broken because we need to be
 141          * able to loop on the threads and merge the ones that are the same process some how.
 142          */
 143         for (; cnt < maxcnt && p != NULL; p = LIST_NEXT(&proc, p_list)) {
 144                 memset(kp, 0, sizeof *kp);
 145                 if (KREAD(kd, (u_long)p, &proc)) {
 146                         _kvm_err(kd, kd->program, "can't read proc at %p", p);
 147                         return (-1);
 148                 }
 149                 if (proc.p_state == PRS_NEW)
 150                         continue;
 151                 if (proc.p_state != PRS_ZOMBIE) {
 152                         if (KREAD(kd, (u_long)TAILQ_FIRST(&proc.p_threads),
 153                             &mtd)) {
 154                                 _kvm_err(kd, kd->program,
 155                                     "can't read thread at %p",
 156                                     TAILQ_FIRST(&proc.p_threads));
 157                                 return (-1);
 158                         }
 159                 }
 160                 if (KREAD(kd, (u_long)proc.p_ucred, &ucred) == 0) {
 161                         kp->ki_ruid = ucred.cr_ruid;
 162                         kp->ki_svuid = ucred.cr_svuid;
 163                         kp->ki_rgid = ucred.cr_rgid;
 164                         kp->ki_svgid = ucred.cr_svgid;
 165                         kp->ki_cr_flags = ucred.cr_flags;
 166                         if (ucred.cr_ngroups > KI_NGROUPS) {
 167                                 kp->ki_ngroups = KI_NGROUPS;
 168                                 kp->ki_cr_flags |= KI_CRF_GRP_OVERFLOW;
 169                         } else
 170                                 kp->ki_ngroups = ucred.cr_ngroups;
 171                         kvm_read(kd, (u_long)ucred.cr_groups, kp->ki_groups,
 172                             kp->ki_ngroups * sizeof(gid_t));
 173                         kp->ki_uid = ucred.cr_uid;
 174                         if (ucred.cr_prison != NULL) {
 175                                 if (KREAD(kd, (u_long)ucred.cr_prison, &pr)) {
 176                                         _kvm_err(kd, kd->program,
 177                                             "can't read prison at %p",
 178                                             ucred.cr_prison);
 179                                         return (-1);
 180                                 }
 181                                 kp->ki_jid = pr.pr_id;
 182                         }
 183                 }
 184
 185                 switch(what & ~KERN_PROC_INC_THREAD) {
 186
 187                 case KERN_PROC_GID:
 188                         if (kp->ki_groups[0] != (gid_t)arg)
 189                                 continue;
 190                         break;
 191
 192                 case KERN_PROC_PID:
 193                         if (proc.p_pid != (pid_t)arg)
 194                                 continue;
 195                         break;
 196
 197                 case KERN_PROC_RGID:
 198                         if (kp->ki_rgid != (gid_t)arg)
 199                                 continue;
 200                         break;
 201
 202                 case KERN_PROC_UID:
 203                         if (kp->ki_uid != (uid_t)arg)
 204                                 continue;
 205                         break;
 206
 207                 case KERN_PROC_RUID:
 208                         if (kp->ki_ruid != (uid_t)arg)
 209                                 continue;
 210                         break;
 211                 }
 212                 /*
 213                  * We're going to add another proc to the set.  If this
 214                  * will overflow the buffer, assume the reason is because
 215                  * nprocs (or the proc list) is corrupt and declare an error.
 216                  */
 217                 if (cnt >= maxcnt) {
 218                         _kvm_err(kd, kd->program, "nprocs corrupt");
 219                         return (-1);
 220                 }
 221                 /*
 222                  * gather kinfo_proc
 223                  */
 224                 kp->ki_paddr = p;
 225                 kp->ki_addr = 0;        /* XXX uarea */
 226                 /* kp->ki_kstack = proc.p_thread.td_kstack; XXXKSE */
 227                 kp->ki_args = proc.p_args;
 228                 kp->ki_tracep = proc.p_tracevp;
 229                 kp->ki_textvp = proc.p_textvp;
 230                 kp->ki_fd = proc.p_fd;
 231                 kp->ki_vmspace = proc.p_vmspace;
 232                 if (proc.p_sigacts != NULL) {
 233                         if (KREAD(kd, (u_long)proc.p_sigacts, &sigacts)) {
 234                                 _kvm_err(kd, kd->program,
 235                                     "can't read sigacts at %p", proc.p_sigacts);
 236                                 return (-1);
 237                         }
 238                         kp->ki_sigignore = sigacts.ps_sigignore;
 239                         kp->ki_sigcatch = sigacts.ps_sigcatch;
 240                 }
 241 #if 0
 242                 if ((proc.p_flag & P_INMEM) && proc.p_stats != NULL) {
 243                         if (KREAD(kd, (u_long)proc.p_stats, &pstats)) {
 244                                 _kvm_err(kd, kd->program,
 245                                     "can't read stats at %x", proc.p_stats);
 246                                 return (-1);
 247                         }
 248                         kp->ki_start = pstats.p_start;
 249
 250                         /*
 251                          * XXX: The times here are probably zero and need
 252                          * to be calculated from the raw data in p_rux and
 253                          * p_crux.
 254                          */
 255                         kp->ki_rusage = pstats.p_ru;
 256                         kp->ki_childstime = pstats.p_cru.ru_stime;
 257                         kp->ki_childutime = pstats.p_cru.ru_utime;
 258                         /* Some callers want child-times in a single value */
 259                         timeradd(&kp->ki_childstime, &kp->ki_childutime,
 260                             &kp->ki_childtime);
 261                 }
 262 #endif
 263                 if (proc.p_oppid)
 264                         kp->ki_ppid = proc.p_oppid;
 265                 else if (proc.p_pptr) {
 266                         if (KREAD(kd, (u_long)proc.p_pptr, &pproc)) {
 267                                 _kvm_err(kd, kd->program,
 268                                     "can't read pproc at %p", proc.p_pptr);
 269                                 return (-1);
 270                         }
 271                         kp->ki_ppid = pproc.p_pid;
 272                 } else
 273                         kp->ki_ppid = 0;
 274                 if (proc.p_pgrp == NULL)
 275                         goto nopgrp;
 276                 if (KREAD(kd, (u_long)proc.p_pgrp, &pgrp)) {
 277                         _kvm_err(kd, kd->program, "can't read pgrp at %p",
 278                                  proc.p_pgrp);
 279                         return (-1);
 280                 }
 281                 kp->ki_pgid = pgrp.pg_id;
 282                 kp->ki_jobc = pgrp.pg_jobc;
 283                 if (KREAD(kd, (u_long)pgrp.pg_session, &sess)) {
 284                         _kvm_err(kd, kd->program, "can't read session at %p",
 285                                 pgrp.pg_session);
 286                         return (-1);
 287                 }
 288                 kp->ki_sid = sess.s_sid;
 289                 (void)memcpy(kp->ki_login, sess.s_login,
 290                                                 sizeof(kp->ki_login));
 291                 kp->ki_kiflag = sess.s_ttyvp ? KI_CTTY : 0;
 292                 if (sess.s_leader == p)
 293                         kp->ki_kiflag |= KI_SLEADER;
 294                 if ((proc.p_flag & P_CONTROLT) && sess.s_ttyp != NULL) {
 295                         if (KREAD(kd, (u_long)sess.s_ttyp, &tty)) {
 296                                 _kvm_err(kd, kd->program,
 297                                          "can't read tty at %p", sess.s_ttyp);
 298                                 return (-1);
 299                         }
 300                         if (tty.t_dev != NULL) {
 301                                 if (KREAD(kd, (u_long)tty.t_dev, &t_cdev)) {
 302                                         _kvm_err(kd, kd->program,
 303                                                  "can't read cdev at %p",
 304                                                 tty.t_dev);
 305                                         return (-1);
 306                                 }
 307 #if 0
 308                                 kp->ki_tdev = t_cdev.si_udev;
 309 #else
 310                                 kp->ki_tdev = NODEV;
 311 #endif
 312                         }
 313                         if (tty.t_pgrp != NULL) {
 314                                 if (KREAD(kd, (u_long)tty.t_pgrp, &pgrp)) {
 315                                         _kvm_err(kd, kd->program,
 316                                                  "can't read tpgrp at %p",
 317                                                 tty.t_pgrp);
 318                                         return (-1);
 319                                 }
 320                                 kp->ki_tpgid = pgrp.pg_id;
 321                         } else
 322                                 kp->ki_tpgid = -1;
 323                         if (tty.t_session != NULL) {
 324                                 if (KREAD(kd, (u_long)tty.t_session, &sess)) {
 325                                         _kvm_err(kd, kd->program,
 326                                             "can't read session at %p",
 327                                             tty.t_session);
 328                                         return (-1);
 329                                 }
 330                                 kp->ki_tsid = sess.s_sid;
 331                         }
 332                 } else {
 333 nopgrp:
 334                         kp->ki_tdev = NODEV;
 335                 }
 336                 if ((proc.p_state != PRS_ZOMBIE) && mtd.td_wmesg)
 337                         (void)kvm_read(kd, (u_long)mtd.td_wmesg,
 338                             kp->ki_wmesg, WMESGLEN);
 339
 340                 (void)kvm_read(kd, (u_long)proc.p_vmspace,
 341                     (char *)&vmspace, sizeof(vmspace));
 342                 kp->ki_size = vmspace.vm_map.size;
 343                 /*
 344                  * Approximate the kernel's method of calculating
 345                  * this field.
 346                  */
 347 #define         pmap_resident_count(pm) ((pm)->pm_stats.resident_count)
 348                 kp->ki_rssize = pmap_resident_count(&vmspace.vm_pmap);
 349                 kp->ki_swrss = vmspace.vm_swrss;
 350                 kp->ki_tsize = vmspace.vm_tsize;
 351                 kp->ki_dsize = vmspace.vm_dsize;
 352                 kp->ki_ssize = vmspace.vm_ssize;
 353
 354                 switch (what & ~KERN_PROC_INC_THREAD) {
 355
 356                 case KERN_PROC_PGRP:
 357                         if (kp->ki_pgid != (pid_t)arg)
 358                                 continue;
 359                         break;
 360
 361                 case KERN_PROC_SESSION:
 362                         if (kp->ki_sid != (pid_t)arg)
 363                                 continue;
 364                         break;
 365
 366                 case KERN_PROC_TTY:
 367                         if ((proc.p_flag & P_CONTROLT) == 0 ||
 368                              kp->ki_tdev != (dev_t)arg)
 369                                 continue;
 370                         break;
 371                 }
 372                 if (proc.p_comm[0] != 0)
 373                         strlcpy(kp->ki_comm, proc.p_comm, MAXCOMLEN);
 374                 (void)kvm_read(kd, (u_long)proc.p_sysent, (char *)&sysent,
 375                     sizeof(sysent));
 376                 (void)kvm_read(kd, (u_long)sysent.sv_name, (char *)&svname,
 377                     sizeof(svname));
 378                 if (svname[0] != 0)
 379                         strlcpy(kp->ki_emul, svname, KI_EMULNAMELEN);
 380                 if ((proc.p_state != PRS_ZOMBIE) &&
 381                     (mtd.td_blocked != 0)) {
 382                         kp->ki_kiflag |= KI_LOCKBLOCK;
 383                         if (mtd.td_lockname)
 384                                 (void)kvm_read(kd,
 385                                     (u_long)mtd.td_lockname,
 386                                     kp->ki_lockname, LOCKNAMELEN);
 387                         kp->ki_lockname[LOCKNAMELEN] = 0;
 388                 }
 389                 kp->ki_runtime = cputick2usec(proc.p_rux.rux_runtime);
 390                 kp->ki_pid = proc.p_pid;
 391                 kp->ki_siglist = proc.p_siglist;
 392                 SIGSETOR(kp->ki_siglist, mtd.td_siglist);
 393                 kp->ki_sigmask = mtd.td_sigmask;
 394                 kp->ki_xstat = KW_EXITCODE(proc.p_xexit, proc.p_xsig);
 395                 kp->ki_acflag = proc.p_acflag;
 396                 kp->ki_lock = proc.p_lock;
 397                 if (proc.p_state != PRS_ZOMBIE) {
 398                         kp->ki_swtime = (ticks - proc.p_swtick) / hz;
 399                         kp->ki_flag = proc.p_flag;
 400                         kp->ki_sflag = 0;
 401                         kp->ki_nice = proc.p_nice;
 402                         kp->ki_traceflag = proc.p_traceflag;
 403                         if (proc.p_state == PRS_NORMAL) {
 404                                 if (TD_ON_RUNQ(&mtd) ||
 405                                     TD_CAN_RUN(&mtd) ||
 406                                     TD_IS_RUNNING(&mtd)) {
 407                                         kp->ki_stat = SRUN;
 408                                 } else if (mtd.td_state ==
 409                                     TDS_INHIBITED) {
 410                                         if (P_SHOULDSTOP(&proc)) {
 411                                                 kp->ki_stat = SSTOP;
 412                                         } else if (
 413                                             TD_IS_SLEEPING(&mtd)) {
 414                                                 kp->ki_stat = SSLEEP;
 415                                         } else if (TD_ON_LOCK(&mtd)) {
 416                                                 kp->ki_stat = SLOCK;
 417                                         } else {
 418                                                 kp->ki_stat = SWAIT;
 419                                         }
 420                                 }
 421                         } else {
 422                                 kp->ki_stat = SIDL;
 423                         }
 424                         /* Stuff from the thread */
 425                         kp->ki_pri.pri_level = mtd.td_priority;
 426                         kp->ki_pri.pri_native = mtd.td_base_pri;
 427                         kp->ki_lastcpu = mtd.td_lastcpu;
 428                         kp->ki_wchan = mtd.td_wchan;
 429                         kp->ki_oncpu = mtd.td_oncpu;
 430                         if (mtd.td_name[0] != '\0')
 431                                 strlcpy(kp->ki_tdname, mtd.td_name, sizeof(kp->ki_tdname));
 432                         kp->ki_pctcpu = 0;
 433                         kp->ki_rqindex = 0;
 434
 435                         /*
 436                          * Note: legacy fields; wraps at NO_CPU_OLD or the
 437                          * old max CPU value as appropriate
 438                          */
 439                         if (mtd.td_lastcpu == NOCPU)
 440                                 kp->ki_lastcpu_old = NOCPU_OLD;
 441                         else if (mtd.td_lastcpu > MAXCPU_OLD)
 442                                 kp->ki_lastcpu_old = MAXCPU_OLD;
 443                         else
 444                                 kp->ki_lastcpu_old = mtd.td_lastcpu;
 445
 446                         if (mtd.td_oncpu == NOCPU)
 447                                 kp->ki_oncpu_old = NOCPU_OLD;
 448                         else if (mtd.td_oncpu > MAXCPU_OLD)
 449                                 kp->ki_oncpu_old = MAXCPU_OLD;
 450                         else
 451                                 kp->ki_oncpu_old = mtd.td_oncpu;
 452                 } else {
 453                         kp->ki_stat = SZOMB;
 454                 }
 455                 kp->ki_tdev_freebsd11 = kp->ki_tdev; /* truncate */
 456                 bcopy(&kinfo_proc, bp, sizeof(kinfo_proc));
 457                 ++bp;
 458                 ++cnt;
 459         }
 460         return (cnt);
 461 }
 462
 463 /*
 464  * Build proc info array by reading in proc list from a crash dump.
 465  * Return number of procs read.  maxcnt is the max we will read.
 466  */
 467 static int
 468 kvm_deadprocs(kvm_t *kd, int what, int arg, u_long a_allproc,
 469     u_long a_zombproc, int maxcnt)
 470 {
 471         struct kinfo_proc *bp = kd->procbase;
 472         int acnt, zcnt;
 473         struct proc *p;
 474
 475         if (KREAD(kd, a_allproc, &p)) {
 476                 _kvm_err(kd, kd->program, "cannot read allproc");
 477                 return (-1);
 478         }
 479         acnt = kvm_proclist(kd, what, arg, p, bp, maxcnt);
 480         if (acnt < 0)
 481                 return (acnt);
 482
 483         if (KREAD(kd, a_zombproc, &p)) {
 484                 _kvm_err(kd, kd->program, "cannot read zombproc");
 485                 return (-1);
 486         }
 487         zcnt = kvm_proclist(kd, what, arg, p, bp + acnt, maxcnt - acnt);
 488         if (zcnt < 0)
 489                 zcnt = 0;
 490
 491         return (acnt + zcnt);
 492 }
 493
 494 struct kinfo_proc *
 495 kvm_getprocs(kvm_t *kd, int op, int arg, int *cnt)
 496 {
 497         int mib[4], st, nprocs;
 498         size_t size, osize;
 499         int temp_op;
 500
 501         if (kd->procbase != 0) {
 502                 free((void *)kd->procbase);
 503                 /*
 504                  * Clear this pointer in case this call fails.  Otherwise,
 505                  * kvm_close() will free it again.
 506                  */
 507                 kd->procbase = 0;
 508         }
 509         if (ISALIVE(kd)) {
 510                 size = 0;
 511                 mib[0] = CTL_KERN;
 512                 mib[1] = KERN_PROC;
 513                 mib[2] = op;
 514                 mib[3] = arg;
 515                 temp_op = op & ~KERN_PROC_INC_THREAD;
 516                 st = sysctl(mib,
 517                     temp_op == KERN_PROC_ALL || temp_op == KERN_PROC_PROC ?
 518                     3 : 4, NULL, &size, NULL, 0);
 519                 if (st == -1) {
 520                         _kvm_syserr(kd, kd->program, "kvm_getprocs");
 521                         return (0);
 522                 }
 523                 /*
 524                  * We can't continue with a size of 0 because we pass
 525                  * it to realloc() (via _kvm_realloc()), and passing 0
 526                  * to realloc() results in undefined behavior.
 527                  */
 528                 if (size == 0) {
 529                         /*
 530                          * XXX: We should probably return an invalid,
 531                          * but non-NULL, pointer here so any client
 532                          * program trying to dereference it will
 533                          * crash.  However, _kvm_freeprocs() calls
 534                          * free() on kd->procbase if it isn't NULL,
 535                          * and free()'ing a junk pointer isn't good.
 536                          * Then again, _kvm_freeprocs() isn't used
 537                          * anywhere . . .
 538                          */
 539                         kd->procbase = _kvm_malloc(kd, 1);
 540                         goto liveout;
 541                 }
 542                 do {
 543                         size += size / 10;
 544                         kd->procbase = (struct kinfo_proc *)
 545                             _kvm_realloc(kd, kd->procbase, size);
 546                         if (kd->procbase == NULL)
 547                                 return (0);
 548                         osize = size;
 549                         st = sysctl(mib, temp_op == KERN_PROC_ALL ||
 550                             temp_op == KERN_PROC_PROC ? 3 : 4,
 551                             kd->procbase, &size, NULL, 0);
 552                 } while (st == -1 && errno == ENOMEM && size == osize);
 553                 if (st == -1) {
 554                         _kvm_syserr(kd, kd->program, "kvm_getprocs");
 555                         return (0);
 556                 }
 557                 /*
 558                  * We have to check the size again because sysctl()
 559                  * may "round up" oldlenp if oldp is NULL; hence it
 560                  * might've told us that there was data to get when
 561                  * there really isn't any.
 562                  */
 563                 if (size > 0 &&
 564                     kd->procbase->ki_structsize != sizeof(struct kinfo_proc)) {
 565                         _kvm_err(kd, kd->program,
 566                             "kinfo_proc size mismatch (expected %zu, got %d)",
 567                             sizeof(struct kinfo_proc),
 568                             kd->procbase->ki_structsize);
 569                         return (0);
 570                 }
 571 liveout:
 572                 nprocs = size == 0 ? 0 : size / kd->procbase->ki_structsize;
 573         } else {
 574                 struct nlist nl[7], *p;
 575
 576                 nl[0].n_name = "_nprocs";
 577                 nl[1].n_name = "_allproc";
 578                 nl[2].n_name = "_zombproc";
 579                 nl[3].n_name = "_ticks";
 580                 nl[4].n_name = "_hz";
 581                 nl[5].n_name = "_cpu_tick_frequency";
 582                 nl[6].n_name = 0;
 583
 584                 if (!kd->arch->ka_native(kd)) {
 585                         _kvm_err(kd, kd->program,
 586                             "cannot read procs from non-native core");
 587                         return (0);
 588                 }
 589
 590                 if (kvm_nlist(kd, nl) != 0) {
 591                         for (p = nl; p->n_type != 0; ++p)
 592                                 ;
 593                         _kvm_err(kd, kd->program,
 594                                  "%s: no such symbol", p->n_name);
 595                         return (0);
 596                 }
 597                 if (KREAD(kd, nl[0].n_value, &nprocs)) {
 598                         _kvm_err(kd, kd->program, "can't read nprocs");
 599                         return (0);
 600                 }
 601                 if (KREAD(kd, nl[3].n_value, &ticks)) {
 602                         _kvm_err(kd, kd->program, "can't read ticks");
 603                         return (0);
 604                 }
 605                 if (KREAD(kd, nl[4].n_value, &hz)) {
 606                         _kvm_err(kd, kd->program, "can't read hz");
 607                         return (0);
 608                 }
 609                 if (KREAD(kd, nl[5].n_value, &cpu_tick_frequency)) {
 610                         _kvm_err(kd, kd->program,
 611                             "can't read cpu_tick_frequency");
 612                         return (0);
 613                 }
 614                 size = nprocs * sizeof(struct kinfo_proc);
 615                 kd->procbase = (struct kinfo_proc *)_kvm_malloc(kd, size);
 616                 if (kd->procbase == NULL)
 617                         return (0);
 618
 619                 nprocs = kvm_deadprocs(kd, op, arg, nl[1].n_value,
 620                                       nl[2].n_value, nprocs);
 621                 if (nprocs <= 0) {
 622                         _kvm_freeprocs(kd);
 623                         nprocs = 0;
 624                 }
 625 #ifdef notdef
 626                 else {
 627                         size = nprocs * sizeof(struct kinfo_proc);
 628                         kd->procbase = realloc(kd->procbase, size);
 629                 }
 630 #endif
 631         }
 632         *cnt = nprocs;
 633         return (kd->procbase);
 634 }
 635
 636 void
 637 _kvm_freeprocs(kvm_t *kd)
 638 {
 639
 640         free(kd->procbase);
 641         kd->procbase = NULL;
 642 }
 643
 644 void *
 645 _kvm_realloc(kvm_t *kd, void *p, size_t n)
 646 {
 647         void *np;
 648
 649         np = reallocf(p, n);
 650         if (np == NULL)
 651                 _kvm_err(kd, kd->program, "out of memory");
 652         return (np);
 653 }
 654
 655 /*
 656  * Get the command args or environment.
 657  */
 658 static char **
 659 kvm_argv(kvm_t *kd, const struct kinfo_proc *kp, int env, int nchr)
 660 {
 661         int oid[4];
 662         int i;
 663         size_t bufsz;
 664         static int buflen;
 665         static char *buf, *p;
 666         static char **bufp;
 667         static int argc;
 668         char **nbufp;
 669
 670         if (!ISALIVE(kd)) {
 671                 _kvm_err(kd, kd->program,
 672                     "cannot read user space from dead kernel");
 673                 return (NULL);
 674         }
 675
 676         if (nchr == 0 || nchr > ARG_MAX)
 677                 nchr = ARG_MAX;
 678         if (buflen == 0) {
 679                 buf = malloc(nchr);
 680                 if (buf == NULL) {
 681                         _kvm_err(kd, kd->program, "cannot allocate memory");
 682                         return (NULL);
 683                 }
 684                 argc = 32;
 685                 bufp = malloc(sizeof(char *) * argc);
 686                 if (bufp == NULL) {
 687                         free(buf);
 688                         buf = NULL;
 689                         _kvm_err(kd, kd->program, "cannot allocate memory");
 690                         return (NULL);
 691                 }
 692                 buflen = nchr;
 693         } else if (nchr > buflen) {
 694                 p = realloc(buf, nchr);
 695                 if (p != NULL) {
 696                         buf = p;
 697                         buflen = nchr;
 698                 }
 699         }
 700         oid[0] = CTL_KERN;
 701         oid[1] = KERN_PROC;
 702         oid[2] = env ? KERN_PROC_ENV : KERN_PROC_ARGS;
 703         oid[3] = kp->ki_pid;
 704         bufsz = buflen;
 705         if (sysctl(oid, 4, buf, &bufsz, 0, 0) == -1) {
 706                 /*
 707                  * If the supplied buf is too short to hold the requested
 708                  * value the sysctl returns with ENOMEM. The buf is filled
 709                  * with the truncated value and the returned bufsz is equal
 710                  * to the requested len.
 711                  */
 712                 if (errno != ENOMEM || bufsz != (size_t)buflen)
 713                         return (NULL);
 714                 buf[bufsz - 1] = '\0';
 715                 errno = 0;
 716         } else if (bufsz == 0)
 717                 return (NULL);
 718         i = 0;
 719         p = buf;
 720         do {
 721                 bufp[i++] = p;
 722                 p += strlen(p) + 1;
 723                 if (i >= argc) {
 724                         argc += argc;
 725                         nbufp = realloc(bufp, sizeof(char *) * argc);
 726                         if (nbufp == NULL)
 727                                 return (NULL);
 728                         bufp = nbufp;
 729                 }
 730         } while (p < buf + bufsz);
 731         bufp[i++] = 0;
 732         return (bufp);
 733 }
 734
 735 char **
 736 kvm_getargv(kvm_t *kd, const struct kinfo_proc *kp, int nchr)
 737 {
 738         return (kvm_argv(kd, kp, 0, nchr));
 739 }
 740
 741 char **
 742 kvm_getenvv(kvm_t *kd, const struct kinfo_proc *kp, int nchr)
 743 {
 744         return (kvm_argv(kd, kp, 1, nchr));
 745 }