/*
  *  md5 based hashtab
  *
  *  Copyright (C) 2008 Sourcefire, Inc.
  *
  *  Authors: aCaB <acab@clamav.net>
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License version 2 as
  *  published by the Free Software Foundation.
  *
  *  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.
  */
 
 #if HAVE_CONFIG_H
 #include "clamav-config.h"
 #endif
 

 #include <stdlib.h>
 #if HAVE_STRING_H
 #include <string.h>
 #endif
 

 #include "uniq.h"

 #include "others.h"

 #include "md5.h"
 
 struct uniq *uniq_init(uint32_t count) {
   struct uniq *U;
 
   if(!count) return NULL;
   U = cli_calloc(1, sizeof(*U));
   if(!U) return NULL;
 
   U->md5s = cli_malloc(count * sizeof(*U->md5s));
   if(!U->md5s) {
     uniq_free(U);
     return NULL;
   }
 
   return U;
 }
 
 void uniq_free(struct uniq *U) {
   free(U->md5s);
   free(U);
 }
 
 uint32_t uniq_add(struct uniq *U, const char *key, uint32_t key_len, char **rhash) {
   unsigned int i;
   uint8_t digest[16];
   cli_md5_ctx md5;

   struct UNIQMD5 *m = NULL;

 
   cli_md5_init(&md5);
   cli_md5_update(&md5, key, key_len);
   cli_md5_final(digest, &md5);
 

   if(U->items && U->md5s[U->idx[*digest]].md5[0]==*digest)
     for(m=&U->md5s[U->idx[*digest]]; m; m=m->next)
       if(!memcmp(&digest[1], &m->md5[1], 15)) break;

   if(!m) {
     const char HEX[] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' };
 
     m = &U->md5s[U->items];

     m->count = 0;

 
     if(U->items && U->md5s[U->idx[*digest]].md5[0]==*digest)
       m->next = &U->md5s[U->idx[*digest]];
     else
       m->next = NULL;
 
     U->idx[*digest]=U->items;
 

     for(i = 0; i < 16; i++) {
       m->name[i*2] = HEX[digest[i]>>4 & 0xf];
       m->name[i*2+1] = HEX[digest[i] & 0xf];

       m->md5[i] = digest[i];

     }
     m->name[32] = '\0';
   }

   U->items++;
   if(rhash) *rhash = m->name;
   return m->count++;
 }
 
 uint32_t uniq_get(struct uniq *U, const char *key, uint32_t key_len, char **rhash) {
   uint8_t digest[16];
   cli_md5_ctx md5;

   struct UNIQMD5 *m = NULL;

 
   cli_md5_init(&md5);
   cli_md5_update(&md5, key, key_len);
   cli_md5_final(digest, &md5);
 

   if(!U->items || U->md5s[U->idx[*digest]].md5[0]!=*digest)
     return 0;
 
   for(m=&U->md5s[U->idx[*digest]]; m; m=m->next) {
     if(memcmp(&digest[1], &m->md5[1], 15)) continue;
     if(rhash) *rhash = m->name;
     return m->count;

   }
 
   return 0;
 }