8264 want support for promoting datasets in libzfs_core

*** 28,37 ****
--- 28,38 ----
   * Copyright (c) 2013 Martin Matuska. All rights reserved.
   * Copyright (c) 2013 Steven Hartland. All rights reserved.
   * Copyright (c) 2014 Integros [integros.com]
   * Copyright 2016 Nexenta Systems, Inc.
   * Copyright 2016 Igor Kozhukhov <ikozhukhov@gmail.com>
+  * Copyright 2017 RackTop Systems.
   */
  
  #include <ctype.h>
  #include <errno.h>
  #include <libintl.h>
*** 3626,3637 ****
   */
  int
  zfs_promote(zfs_handle_t *zhp)
  {
          libzfs_handle_t *hdl = zhp->zfs_hdl;
!         zfs_cmd_t zc = { 0 };
!         char parent[MAXPATHLEN];
          int ret;
          char errbuf[1024];
  
          (void) snprintf(errbuf, sizeof (errbuf), dgettext(TEXT_DOMAIN,
              "cannot promote '%s'"), zhp->zfs_name);
--- 3627,3637 ----
   */
  int
  zfs_promote(zfs_handle_t *zhp)
  {
          libzfs_handle_t *hdl = zhp->zfs_hdl;
!         char snapname[MAXPATHLEN];
          int ret;
          char errbuf[1024];
  
          (void) snprintf(errbuf, sizeof (errbuf), dgettext(TEXT_DOMAIN,
              "cannot promote '%s'"), zhp->zfs_name);
*** 3640,3670 ****
                  zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                      "snapshots can not be promoted"));
                  return (zfs_error(hdl, EZFS_BADTYPE, errbuf));
          }
  
!         (void) strlcpy(parent, zhp->zfs_dmustats.dds_origin, sizeof (parent));
!         if (parent[0] == '\0') {
                  zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                      "not a cloned filesystem"));
                  return (zfs_error(hdl, EZFS_BADTYPE, errbuf));
          }
  
!         (void) strlcpy(zc.zc_value, zhp->zfs_dmustats.dds_origin,
!             sizeof (zc.zc_value));
!         (void) strlcpy(zc.zc_name, zhp->zfs_name, sizeof (zc.zc_name));
!         ret = zfs_ioctl(hdl, ZFS_IOC_PROMOTE, &zc);
  
          if (ret != 0) {
                  int save_errno = errno;
  
                  switch (save_errno) {
                  case EEXIST:
                          /* There is a conflicting snapshot name. */
                          zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                              "conflicting snapshot '%s' from parent '%s'"),
!                             zc.zc_string, parent);
                          return (zfs_error(hdl, EZFS_EXISTS, errbuf));
  
                  default:
                          return (zfs_standard_error(hdl, save_errno, errbuf));
                  }
--- 3640,3666 ----
                  zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                      "snapshots can not be promoted"));
                  return (zfs_error(hdl, EZFS_BADTYPE, errbuf));
          }
  
!         if (zhp->zfs_dmustats.dds_origin[0] == '\0') {
                  zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                      "not a cloned filesystem"));
                  return (zfs_error(hdl, EZFS_BADTYPE, errbuf));
          }
  
!         ret = lzc_promote(zhp->zfs_name, snapname, sizeof(snapname));
  
          if (ret != 0) {
                  int save_errno = errno;
  
                  switch (save_errno) {
                  case EEXIST:
                          /* There is a conflicting snapshot name. */
                          zfs_error_aux(hdl, dgettext(TEXT_DOMAIN,
                              "conflicting snapshot '%s' from parent '%s'"),
!                             snapname, zhp->zfs_dmustats.dds_origin);
                          return (zfs_error(hdl, EZFS_EXISTS, errbuf));
  
                  default:
                          return (zfs_standard_error(hdl, save_errno, errbuf));
                  }