OS-4348 libnsl should seek netconfig file in native root
Reviewed by: Robert Mustacchi <rm@joyent.com>
OS-3812 lxbrand nfs mounting fails

*** 20,29 ****
--- 20,30 ----
   */
  
  /*
   * Copyright 2007 Sun Microsystems, Inc.  All rights reserved.
   * Use is subject to license terms.
+  * Copyright 2015 Joyent, Inc.
   */
  
  /*      Copyright (c) 1983, 1984, 1985, 1986, 1987, 1988, 1989 AT&T     */
  /*        All Rights Reserved   */
  
*** 30,41 ****
  /*
   * Portions of this source code were derived from Berkeley 4.3 BSD
   * under license from the Regents of the University of California.
   */
  
- #pragma ident   "%Z%%M% %I%     %E% SMI"
- 
  #include "mt.h"
  #include "../rpc/rpc_mt.h"              /* for MT declarations only */
  #include <rpc/types.h>
  #include <stdio.h>
  #include <stdlib.h>
--- 31,40 ----
*** 43,52 ****
--- 42,52 ----
  #include <ctype.h>
  #include <netconfig.h>
  #include <malloc.h>
  #include <libintl.h>
  #include <syslog.h>
+ #include <zone.h>
  #include "netcspace.h"
  
  #define FAILURE  (unsigned)(-1)
  
  /*
*** 68,77 ****
--- 68,80 ----
  static void free_entry(void *);
  static struct netconfig *netconfig_dup(struct netconfig *);
  
  extern const char __nsl_dom[];
  
+ static int (*brand_get_sz)(void) = NULL;
+ static struct netconfig *(*brand_get_net_ent)(int) = NULL;
+ 
  /*
   *      Static global variables used by the library procedures:
   *
   *      netpp - points to the beginning of the list of netconfig
   *              entries used by setnetconfig() and setnetpath().
*** 253,262 ****
--- 256,273 ----
  freenetconfigent(struct netconfig *netp)
  {
          netconfig_free(netp);
  }
  
+ void
+ _nsl_brand_set_hooks(int (*set_sz_func)(void),
+     struct netconfig *(*get_ent_func)(int))
+ {
+         brand_get_sz = set_sz_func;
+         brand_get_net_ent = get_ent_func;
+ }
+ 
  /*
   *      getnetlist() reads the netconfig file and creates a
   *      NULL-terminated list of entries.
   *      Returns the pointer to the head of the list or a NULL
   *      on failure.
*** 263,279 ****
   */
  
  static struct netconfig **
  getnetlist(void)
  {
!         char line[BUFSIZ];      /* holds each line of NETCONFIG */
!         FILE *fp;               /* file stream for NETCONFIG */
          struct netconfig **listpp; /* the beginning of the netconfig list */
          struct netconfig **tpp; /* used to traverse the netconfig list */
          int count;              /* the number of entries in file */
  
!         if ((fp = fopen(NETCONFIG, "rF")) == NULL) {
                  nc_error = NC_OPENFAIL;
                  return (NULL);
          }
  
          count = 0;
--- 274,303 ----
   */
  
  static struct netconfig **
  getnetlist(void)
  {
!         FILE *fp = NULL;        /* file stream for NETCONFIG */
          struct netconfig **listpp; /* the beginning of the netconfig list */
          struct netconfig **tpp; /* used to traverse the netconfig list */
          int count;              /* the number of entries in file */
+         char nc_path[MAXPATHLEN];
+         const char *zroot = zone_get_nroot();
  
!         /*
!          * If we are running in a branded zone, ensure we use the "/native"
!          * prefix when opening the netconfig file:
!          */
!         (void) snprintf(nc_path, sizeof (nc_path), "%s%s", zroot != NULL ?
!             zroot : "", NETCONFIG);
! 
!         if (brand_get_sz != NULL) {
!                 count = brand_get_sz();
!         } else {
!                 char line[BUFSIZ];      /* holds each line of NETCONFIG */
! 
!                 if ((fp = fopen(nc_path, "rF")) == NULL) {
                          nc_error = NC_OPENFAIL;
                          return (NULL);
                  }
  
                  count = 0;
*** 281,303 ****
--- 305,342 ----
                          if (!(blank(line) || comment(line))) {
                                  ++count;
                          }
                  }
                  rewind(fp);
+         }
  
          if (count == 0) {
                  nc_error = NC_NOTFOUND;
+                 if (fp != NULL)
                          (void) fclose(fp);
                  return (NULL);
          }
+ 
          if ((listpp = malloc((count + 1) *
              sizeof (struct netconfig *))) == NULL) {
                  nc_error = NC_NOMEM;
+                 if (fp != NULL)
                          (void) fclose(fp);
                  return (NULL);
          }
  
+         if (brand_get_net_ent != NULL) {
+                 int i;
+ 
+                 tpp = listpp;
+                 for (i = 0; i < count; i++) {
+                         *tpp = brand_get_net_ent(i);
+                         tpp++;
+                 }
+                 *tpp = NULL;
+                 nc_error = NC_NOMOREENTRIES;
+         } else {
                  /*
                   *      The following loop fills in the list (loops until
                   *      fgetnetconfig() returns a NULL) and counts the
                   *      number of entries placed in the list.  Note that
                   *      when the loop is completed, the last entry in the
*** 309,318 ****
--- 348,359 ----
                          ;
                  (void) fclose(fp);
  
                  if (nc_error != NC_NOMOREENTRIES) /* Something is screwed up */
                          netlist_free(&listpp);
+         }
+ 
          return (listpp);
  }
  
  /*
   *      fgetnetconfig() parses a line of the netconfig file into