11626 introduce /etc/versions/build
11627 clean up UUID code for ::status

*** 21,31 ****
  /*
   * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
   */
  
  /*
!  * Copyright (c) 2013, Joyent, Inc.  All rights reserved.
   */
  
  /*
   * Libkvm Kernel Target
   *
--- 21,31 ----
  /*
   * Copyright (c) 1999, 2010, Oracle and/or its affiliates. All rights reserved.
   */
  
  /*
!  * Copyright 2019 Joyent, Inc.
   */
  
  /*
   * Libkvm Kernel Target
   *
*** 49,58 ****
--- 49,59 ----
  #include <sys/kobj_impl.h>
  #include <sys/utsname.h>
  #include <sys/panic.h>
  #include <sys/dumphdr.h>
  #include <sys/dumpadm.h>
+ #include <sys/uuid.h>
  
  #include <dlfcn.h>
  #include <libctf.h>
  #include <string.h>
  #include <fcntl.h>
*** 66,75 ****
--- 67,77 ----
  #include <mdb/mdb_io_impl.h>
  #include <mdb/mdb_ctf.h>
  #include <mdb/mdb_kvm.h>
  #include <mdb/mdb_module.h>
  #include <mdb/mdb_kb.h>
+ #include <mdb/mdb_ks.h>
  #include <mdb/mdb.h>
  
  #define KT_RELOC_BUF(buf, obase, nbase) \
          ((uintptr_t)(buf) - (uintptr_t)(obase) + (uintptr_t)(nbase))
  
*** 92,101 ****
--- 94,105 ----
  } kt_maparg_t;
  
  static const char KT_MODULE[] = "mdb_ks";
  static const char KT_CTFPARENT[] = "genunix";
  
+ static void (*print_buildversion)(void);
+ 
  static void
  kt_load_module(kt_data_t *kt, mdb_tgt_t *t, kt_module_t *km)
  {
          km->km_data = mdb_alloc(km->km_datasz, UM_SLEEP);
  
*** 483,506 ****
          }
  
          mdb_printf("operating system: %s %s (%s)\n",
              uts.release, uts.version, uts.machine);
  
          if (kt->k_dumphdr) {
                  dumphdr_t *dh = kt->k_dumphdr;
  
                  mdb_printf("image uuid: %s\n", dh->dump_uuid[0] != '\0' ?
                      dh->dump_uuid : "(not set)");
                  mdb_printf("panic message: %s\n", dh->dump_panicstring);
  
                  kt->k_dump_print_content(dh, kt->k_dumpcontent);
          } else {
!                 char uuid[37];
  
!                 if (mdb_readsym(uuid, 37, "dump_osimage_uuid") == 37 &&
!                     uuid[36] == '\0') {
!                         mdb_printf("image uuid: %s\n", uuid);
                  }
          }
  
          return (DCMD_OK);
  }
--- 487,515 ----
          }
  
          mdb_printf("operating system: %s %s (%s)\n",
              uts.release, uts.version, uts.machine);
  
+         if (print_buildversion != NULL)
+                 print_buildversion();
+ 
          if (kt->k_dumphdr) {
                  dumphdr_t *dh = kt->k_dumphdr;
  
                  mdb_printf("image uuid: %s\n", dh->dump_uuid[0] != '\0' ?
                      dh->dump_uuid : "(not set)");
                  mdb_printf("panic message: %s\n", dh->dump_panicstring);
  
                  kt->k_dump_print_content(dh, kt->k_dumpcontent);
          } else {
!                 char uuid[UUID_PRINTABLE_STRING_LENGTH];
  
!                 if (mdb_readsym(uuid, sizeof (uuid),
!                     "dump_osimage_uuid") == sizeof (uuid) &&
!                     uuid[sizeof (uuid) - 1] == '\0') {
!                         mdb_printf("image uuid: %s\n", uuid[0] != '\0' ?
!                             uuid : "(not set)");
                  }
          }
  
          return (DCMD_OK);
  }
*** 580,589 ****
--- 589,601 ----
                  if (mdb_module_load(KT_MODULE, MDB_MOD_GLOBAL) < 0) {
                          warn("failed to load kernel support module -- "
                              "some modules may not load\n");
                  }
  
+                 print_buildversion = (void (*)(void))dlsym(RTLD_NEXT,
+                     "mdb_print_buildversion");
+ 
                  if (mdb_prop_postmortem && kt->k_dumphdr != NULL) {
                          sym = dlsym(RTLD_NEXT, "mdb_dump_print_content");
                          if (sym != NULL)
                                  kt->k_dump_print_content = (void (*)())sym;