/*
   Bacula® - The Network Backup Solution

   Copyright (C) 2007 Kern Sibbald

   The main author of Bacula is Kern Sibbald, with contributions from
   many others, a complete list can be found in the file AUTHORS.
   This program is Free Software; you can redistribute it and/or
   modify it under the terms of version two of the GNU General Public
   License as published by the Free Software Foundation, which is 
   listed in the file LICENSE.

   This program is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
   General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
   02110-1301, USA.

   Bacula® is a registered trademark of John Walker.
   The licensor of Bacula is the Free Software Foundation Europe
   (FSFE), Fiduciary Program, Sumatrastrasse 25, 8006 Zürich,
   Switzerland, email:ftf@fsfeurope.org.
*/
/*
 * Written by Kern Sibbald, July 2007 to replace idcache.c
 * 
 *  Program to convert uid and gid into names, and cache the results
 *   for preformance reasons.
 *
 *  Version $Id: guid_to_name.c 5502 2007-09-09 08:00:09Z kerns $
 */

#include "bacula.h"

#ifndef WIN32
static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
#endif

struct guitem {
   dlink link;
   char *name;
   union {
      uid_t uid;
      gid_t gid;
   };
};


guid_list *new_guid_list()
{
   guid_list *list;
   guitem *item = NULL;
   list = (guid_list *)malloc(sizeof(guid_list));
   list->uid_list = New(dlist(item, &item->link));
   list->gid_list = New(dlist(item, &item->link));
   return list;
}

void free_guid_list(guid_list *list)
{
   guitem *item;
   foreach_dlist(item, list->uid_list) {
      free(item->name);
   }
   foreach_dlist(item, list->gid_list) {
      free(item->name);
   }
   delete list->uid_list;
   delete list->gid_list;
   free(list);
}

static int uid_compare(void *item1, void *item2)
{
   guitem *i1 = (guitem *)item1;
   guitem *i2 = (guitem *)item2;
   if (i1->uid < i2->uid) {
      return -1;
   } else if (i1->uid > i2->uid) {
      return 1;
   } else {
      return 0;
   }
}

static int gid_compare(void *item1, void *item2)
{
   guitem *i1 = (guitem *)item1;
   guitem *i2 = (guitem *)item2;
   if (i1->gid < i2->gid) {
      return -1;
   } else if (i1->gid > i2->gid) {
      return 1;
   } else {
      return 0;
   }
}


static void get_uidname(uid_t uid, guitem *item)
{
#ifndef HAVE_WIN32
   struct passwd *pwbuf;
   P(mutex);
   pwbuf = getpwuid(uid);
   if (pwbuf != NULL && strcmp(pwbuf->pw_name, "????????") != 0) {
      item->name = bstrdup(pwbuf->pw_name);
   }
   V(mutex);
#endif
}

static void get_gidname(gid_t gid, guitem *item)
{
#ifndef HAVE_WIN32
   struct group *grbuf;
   P(mutex);
   grbuf = getgrgid(gid);
   if (grbuf != NULL && strcmp(grbuf->gr_name, "????????") != 0) {
      item->name = bstrdup(grbuf->gr_name);
   }
   V(mutex);
#endif
}


char *guid_list::uid_to_name(uid_t uid, char *name, int maxlen)
{
   guitem sitem, *item, *fitem;
   sitem.uid = uid;
   char buf[50];

   item = (guitem *)uid_list->binary_search(&sitem, uid_compare);
   Dmsg2(900, "uid=%d item=%p\n", uid, item);
   if (!item) {
      item = (guitem *)malloc(sizeof(guitem));
      item->uid = uid;
      item->name = NULL;
      get_uidname(uid, item);
      if (!item->name) {
         item->name = bstrdup(edit_int64(uid, buf));
         Dmsg2(900, "set uid=%d name=%s\n", uid, item->name);
      }
      fitem = (guitem *)uid_list->binary_insert(item, uid_compare);
      if (fitem != item) {               /* item already there this shouldn't happen */
         free(item);
         item = fitem;   
      }
   }
   bstrncpy(name, item->name, maxlen);
   return name;
}

char *guid_list::gid_to_name(gid_t gid, char *name, int maxlen)
{
   guitem sitem, *item, *fitem;
   sitem.gid = gid;
   char buf[50];

   item = (guitem *)gid_list->binary_search(&sitem, gid_compare);
   if (!item) {
      item = (guitem *)malloc(sizeof(guitem));
      item->gid = gid;
      item->name = NULL;
      get_gidname(gid, item);
      if (!item->name) {
         item->name = bstrdup(edit_int64(gid, buf));
      }
      fitem = (guitem *)gid_list->binary_insert(item, gid_compare);
      if (fitem != item) {               /* item already there this shouldn't happen */
         free(item);
         item = fitem;   
      }
   }

   bstrncpy(name, item->name, maxlen);
   return name;
}

#ifdef TEST_PROGRAM

int main()
{
   int i;
   guid_list *list;
   char ed1[50], ed2[50];
   list = new_guid_list();
   for (i=0; i<1001; i++) {
      printf("uid=%d name=%s  gid=%d name=%s\n", i, list->uid_to_name(i, ed1, sizeof(ed1)),
         i, list->gid_to_name(i, ed2, sizeof(ed2)));
      printf("uid=%d name=%s  gid=%d name=%s\n", i, list->uid_to_name(i, ed1, sizeof(ed1)),
         i, list->gid_to_name(i, ed2, sizeof(ed2)));
   }
    
   free_guid_list(list);
   sm_dump(false);

   return 0;
}
 
#endif