/src/libewf/libewf/libewf_huffman_tree.c

Source (jump to first uncovered line)
/*
 * Huffman tree functions
 *
 * Copyright (C) 2006-2023, Joachim Metz <joachim.metz@gmail.com>
 *
 * Refer to AUTHORS for acknowledgements.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * 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 Lesser General Public License
 * along with this program.  If not, see <https://www.gnu.org/licenses/>.
 */

#include <common.h>
#include <memory.h>
#include <types.h>

#include "libewf_bit_stream.h"
#include "libewf_huffman_tree.h"
#include "libewf_libcerror.h"
#include "libewf_libcnotify.h"

/* Creates a Huffman tree
 * Make sure the value huffman_tree is referencing, is set to NULL
 * Returns 1 if successful or -1 on error
 */
int libewf_huffman_tree_initialize(
     libewf_huffman_tree_t **huffman_tree,
     int number_of_symbols,
     uint8_t maximum_code_size,
     libcerror_error_t **error )
{
  static char *function = "libewf_huffman_tree_initialize";
  size_t array_size     = 0;

  if( huffman_tree == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
     "%s: invalid Huffman tree.",
     function );

    return( -1 );
  }
  if( *huffman_tree != NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_RUNTIME,
     LIBCERROR_RUNTIME_ERROR_VALUE_ALREADY_SET,
     "%s: invalid Huffman tree value already set.",
     function );

    return( -1 );
  }
  if( ( number_of_symbols < 0 )
   || ( number_of_symbols > 1024 ) )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
     LIBCERROR_ARGUMENT_ERROR_VALUE_OUT_OF_BOUNDS,
     "%s: invalid number of symbols value out of bounds.",
     function );

    return( -1 );
  }
  if( maximum_code_size > 32 )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
     LIBCERROR_ARGUMENT_ERROR_VALUE_OUT_OF_BOUNDS,
     "%s: invalid maximum code size value out of bounds.",
     function );

    return( -1 );
  }
  *huffman_tree = memory_allocate_structure(
                   libewf_huffman_tree_t );

  if( *huffman_tree == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_MEMORY,
     LIBCERROR_MEMORY_ERROR_INSUFFICIENT,
     "%s: unable to create Huffman tree.",
     function );

    goto on_error;
  }
  if( memory_set(
       *huffman_tree,
       0,
       sizeof( libewf_huffman_tree_t ) ) == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_MEMORY,
     LIBCERROR_MEMORY_ERROR_SET_FAILED,
     "%s: unable to clear Huffman tree.",
     function );

    memory_free(
     *huffman_tree );

    *huffman_tree = NULL;

    return( -1 );
  }
  array_size = sizeof( uint16_t ) * number_of_symbols;

  ( *huffman_tree )->symbols = (uint16_t *) memory_allocate(
                                             array_size );

  if( ( *huffman_tree )->symbols == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_MEMORY,
     LIBCERROR_MEMORY_ERROR_INSUFFICIENT,
     "%s: unable to create symbols.",
     function );

    goto on_error;
  }
  if( memory_set(
       ( *huffman_tree )->symbols,
       0,
       array_size ) == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_MEMORY,
     LIBCERROR_MEMORY_ERROR_SET_FAILED,
     "%s: unable to clear symbols.",
     function );

    goto on_error;
  }
  array_size = sizeof( int ) * ( maximum_code_size + 1 );

  ( *huffman_tree )->code_size_counts = (int *) memory_allocate(
                                                 array_size );

  if( ( *huffman_tree )->code_size_counts == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_MEMORY,
     LIBCERROR_MEMORY_ERROR_INSUFFICIENT,
     "%s: unable to create code size counts.",
     function );

    goto on_error;
  }
  if( memory_set(
       ( *huffman_tree )->code_size_counts,
       0,
       array_size ) == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_MEMORY,
     LIBCERROR_MEMORY_ERROR_SET_FAILED,
     "%s: unable to clear code size counts.",
     function );

    goto on_error;
  }
  ( *huffman_tree )->maximum_code_size = maximum_code_size;

  return( 1 );

on_error:
  if( *huffman_tree != NULL )
  {
    if( ( *huffman_tree )->code_size_counts != NULL )
    {
      memory_free(
       ( *huffman_tree )->code_size_counts );
    }
    if( ( *huffman_tree )->symbols != NULL )
    {
      memory_free(
       ( *huffman_tree )->symbols );
    }
    memory_free(
     *huffman_tree );

    *huffman_tree = NULL;
  }
  return( -1 );
}

/* Frees a Huffman tree
 * Returns 1 if successful or -1 on error
 */
int libewf_huffman_tree_free(
     libewf_huffman_tree_t **huffman_tree,
     libcerror_error_t **error )
{
  static char *function = "libewf_huffman_tree_free";

  if( huffman_tree == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
     "%s: invalid Huffman tree.",
     function );

    return( -1 );
  }
  if( *huffman_tree != NULL )
  {
    if( ( *huffman_tree )->code_size_counts != NULL )
    {
      memory_free(
       ( *huffman_tree )->code_size_counts );
    }
    if( ( *huffman_tree )->symbols != NULL )
    {
      memory_free(
       ( *huffman_tree )->symbols );
    }
    memory_free(
     *huffman_tree );

    *huffman_tree = NULL;
  }
  return( 1 );
}

/* Builds the Huffman tree
 * Returns 1 on success, 0 if the tree is empty or -1 on error
 */
int libewf_huffman_tree_build(
     libewf_huffman_tree_t *huffman_tree,
     const uint8_t *code_sizes_array,
     int number_of_code_sizes,
     libcerror_error_t **error )
{
  int *symbol_offsets   = NULL;
  static char *function = "libewf_huffman_tree_build";
  size_t array_size     = 0;
  uint16_t symbol       = 0;
  uint8_t bit_index     = 0;
  uint8_t code_size     = 0;
  int code_offset       = 0;
  int left_value        = 0;

  if( huffman_tree == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
     "%s: invalid Huffman tree.",
     function );

    return( -1 );
  }
  if( code_sizes_array == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
     "%s: invalid code sizes array.",
     function );

    return( -1 );
  }
  if( ( number_of_code_sizes < 0 )
   || ( number_of_code_sizes > (int) INT16_MAX ) )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
     LIBCERROR_ARGUMENT_ERROR_VALUE_OUT_OF_BOUNDS,
     "%s: invalid number of code sizes value out of bounds.",
     function );

    return( -1 );
  }
  /* Determine the code size frequencies
   */
  array_size = sizeof( int ) * ( huffman_tree->maximum_code_size + 1 );

  if( memory_set(
       huffman_tree->code_size_counts,
       0,
       array_size ) == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_MEMORY,
     LIBCERROR_MEMORY_ERROR_SET_FAILED,
     "%s: unable to clear code size counts.",
     function );

    goto on_error;
  }
  for( symbol = 0;
       symbol < (uint16_t) number_of_code_sizes;
       symbol++ )
  {
    code_size = code_sizes_array[ symbol ];

    if( code_size > huffman_tree->maximum_code_size )
    {
      libcerror_error_set(
       error,
       LIBCERROR_ERROR_DOMAIN_RUNTIME,
       LIBCERROR_RUNTIME_ERROR_VALUE_OUT_OF_BOUNDS,
       "%s: invalid symbol: %d code size: %" PRIu8 " value out of bounds.",
       function,
       symbol,
       code_size );

      goto on_error;
    }
    huffman_tree->code_size_counts[ code_size ] += 1;
  }
  /* The tree has no codes
   */
  if( huffman_tree->code_size_counts[ 0 ] == number_of_code_sizes )
  {
    return( 0 );
  }
  /* Check if the set of code sizes is incomplete or over-subscribed
   */
  left_value = 1;

  for( bit_index = 1;
       bit_index <= huffman_tree->maximum_code_size;
       bit_index++ )
  {
    left_value <<= 1;
    left_value  -= huffman_tree->code_size_counts[ bit_index ];

    if( left_value < 0 )
    {
      libcerror_error_set(
       error,
       LIBCERROR_ERROR_DOMAIN_RUNTIME,
       LIBCERROR_RUNTIME_ERROR_VALUE_OUT_OF_BOUNDS,
       "%s: code sizes are over-subscribed.",
       function );

      goto on_error;
    }
  }
/* TODO
  if( left_value > 0 )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_RUNTIME,
     LIBCERROR_RUNTIME_ERROR_VALUE_OUT_OF_BOUNDS,
     "%s: code sizes are incomplete.",
     function );

    goto on_error;
  }
*/
  symbol_offsets = (int *) memory_allocate(
                            array_size );

  if( symbol_offsets == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_MEMORY,
     LIBCERROR_MEMORY_ERROR_INSUFFICIENT,
     "%s: unable to create symbol offsets.",
     function );

    goto on_error;
  }
  /* Calculate the offsets to sort the symbols per code size
   */
  symbol_offsets[ 0 ] = 0;
  symbol_offsets[ 1 ] = 0;

  for( bit_index = 1;
       bit_index < huffman_tree->maximum_code_size;
       bit_index++ )
  {
    symbol_offsets[ bit_index + 1 ] = symbol_offsets[ bit_index ] + huffman_tree->code_size_counts[ bit_index ];
  }
  /* Fill the symbols sorted by code size
   */
  for( symbol = 0;
       symbol < (uint16_t) number_of_code_sizes;
       symbol++ )
  {
    code_size = code_sizes_array[ symbol ];

    if( code_size == 0 )
    {
      continue;
    }
    code_offset = symbol_offsets[ code_size ];

    if( ( code_offset < 0 )
     || ( code_offset > number_of_code_sizes ) )
    {
      libcerror_error_set(
       error,
       LIBCERROR_ERROR_DOMAIN_RUNTIME,
       LIBCERROR_RUNTIME_ERROR_VALUE_OUT_OF_BOUNDS,
       "%s: invalid symbol: %" PRIu16 " code offset: %d value out of bounds.",
       function,
       symbol,
       code_offset );

      goto on_error;
    }
    symbol_offsets[ code_size ] += 1;

    huffman_tree->symbols[ code_offset ] = symbol;
  }
  memory_free(
   symbol_offsets );

  return( 1 );

on_error:
  if( symbol_offsets != NULL )
  {
    memory_free(
     symbol_offsets );
  }
  return( -1 );
}

/* Retrieves a symbol based on the Huffman code read from the bit-stream
 * Returns 1 on success or -1 on error
 */
int libewf_huffman_tree_get_symbol_from_bit_stream(
     libewf_huffman_tree_t *huffman_tree,
     libewf_bit_stream_t *bit_stream,
     uint16_t *symbol,
     libcerror_error_t **error )
{
  static char *function  = "libewf_huffman_tree_get_symbol_from_bit_stream";
  uint32_t value_32bit   = 0;
  uint16_t safe_symbol   = 0;
  uint8_t bit_index      = 0;
  int code_size_count    = 0;
  int first_huffman_code = 0;
  int first_index        = 0;
  int huffman_code       = 0;
  int result             = 0;

  if( huffman_tree == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
     "%s: invalid Huffman tree.",
     function );

    return( -1 );
  }
  if( bit_stream == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
     "%s: invalid bit stream.",
     function );

    return( -1 );
  }
  if( symbol == NULL )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
     LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
     "%s: invalid symbol.",
     function );

    return( -1 );
  }
/* TODO get maximum_code_size of bits into local bit buffer */

  for( bit_index = 1;
       bit_index <= huffman_tree->maximum_code_size;
       bit_index++ )
  {
    if( libewf_bit_stream_get_value(
         bit_stream,
         1,
         &value_32bit,
         error ) != 1 )
    {
      libcerror_error_set(
       error,
       LIBCERROR_ERROR_DOMAIN_RUNTIME,
       LIBCERROR_RUNTIME_ERROR_GET_FAILED,
       "%s: unable to retrieve value from bit stream.",
       function );

      return( -1 );
    }
    huffman_code <<= 1;
    huffman_code  |= (int) value_32bit;

    code_size_count = huffman_tree->code_size_counts[ bit_index ];

    if( ( huffman_code - code_size_count ) < first_huffman_code )
    {
      safe_symbol = huffman_tree->symbols[ first_index + ( huffman_code - first_huffman_code ) ];

      result = 1;

      break;
    }
    first_huffman_code  += code_size_count;
    first_huffman_code <<= 1;
    first_index         += code_size_count;
  }
  if( result != 1 )
  {
    libcerror_error_set(
     error,
     LIBCERROR_ERROR_DOMAIN_RUNTIME,
     LIBCERROR_RUNTIME_ERROR_VALUE_OUT_OF_BOUNDS,
     "%s: invalid Huffman code: 0x%08" PRIx32 ".",
     function,
     huffman_code );

    return( -1 );
  }
  *symbol = safe_symbol;

  return( 1 );
}


Coverage Report

Created: 2024-02-25 07:20

Line	Count	Source (jump to first uncovered line)
1		/*
2		* Huffman tree functions
3		*
4		* Copyright (C) 2006-2023, Joachim Metz <joachim.metz@gmail.com>
5		*
6		* Refer to AUTHORS for acknowledgements.
7		*
8		* This program is free software: you can redistribute it and/or modify
9		* it under the terms of the GNU Lesser General Public License as published by
10		* the Free Software Foundation, either version 3 of the License, or
11		* (at your option) any later version.
12		*
13		* This program is distributed in the hope that it will be useful,
14		* but WITHOUT ANY WARRANTY; without even the implied warranty of
15		* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16		* GNU General Public License for more details.
17		*
18		* You should have received a copy of the GNU Lesser General Public License
19		* along with this program. If not, see <https://www.gnu.org/licenses/>.
20		*/
21
22		#include <common.h>
23		#include <memory.h>
24		#include <types.h>
25
26		#include "libewf_bit_stream.h"
27		#include "libewf_huffman_tree.h"
28		#include "libewf_libcerror.h"
29		#include "libewf_libcnotify.h"
30
31		/* Creates a Huffman tree
32		* Make sure the value huffman_tree is referencing, is set to NULL
33		* Returns 1 if successful or -1 on error
34		*/
35		int libewf_huffman_tree_initialize(
36		libewf_huffman_tree_t **huffman_tree,
37		int number_of_symbols,
38		uint8_t maximum_code_size,
39		libcerror_error_t **error )
40	15.5k	{
41	15.5k	static char *function = "libewf_huffman_tree_initialize";
42	15.5k	size_t array_size = 0;
43
44	15.5k	if( huffman_tree == NULL )
45	0	{
46	0	libcerror_error_set(
47	0	error,
48	0	LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
49	0	LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
50	0	"%s: invalid Huffman tree.",
51	0	function );
52
53	0	return( -1 );
54	0	}
55	15.5k	if( *huffman_tree != NULL )
56	0	{
57	0	libcerror_error_set(
58	0	error,
59	0	LIBCERROR_ERROR_DOMAIN_RUNTIME,
60	0	LIBCERROR_RUNTIME_ERROR_VALUE_ALREADY_SET,
61	0	"%s: invalid Huffman tree value already set.",
62	0	function );
63
64	0	return( -1 );
65	0	}
66	15.5k	if( ( number_of_symbols < 0 )
67	15.5k	\|\| ( number_of_symbols > 1024 ) )
68	0	{
69	0	libcerror_error_set(
70	0	error,
71	0	LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
72	0	LIBCERROR_ARGUMENT_ERROR_VALUE_OUT_OF_BOUNDS,
73	0	"%s: invalid number of symbols value out of bounds.",
74	0	function );
75
76	0	return( -1 );
77	0	}
78	15.5k	if( maximum_code_size > 32 )
79	0	{
80	0	libcerror_error_set(
81	0	error,
82	0	LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
83	0	LIBCERROR_ARGUMENT_ERROR_VALUE_OUT_OF_BOUNDS,
84	0	"%s: invalid maximum code size value out of bounds.",
85	0	function );
86
87	0	return( -1 );
88	0	}
89	15.5k	*huffman_tree = memory_allocate_structure(
90	15.5k	libewf_huffman_tree_t );
91
92	15.5k	if( *huffman_tree == NULL )
93	0	{
94	0	libcerror_error_set(
95	0	error,
96	0	LIBCERROR_ERROR_DOMAIN_MEMORY,
97	0	LIBCERROR_MEMORY_ERROR_INSUFFICIENT,
98	0	"%s: unable to create Huffman tree.",
99	0	function );
100
101	0	goto on_error;
102	0	}
103	15.5k	if( memory_set(
104	15.5k	*huffman_tree,
105	15.5k	0,
106	15.5k	sizeof( libewf_huffman_tree_t ) ) == NULL )
107	0	{
108	0	libcerror_error_set(
109	0	error,
110	0	LIBCERROR_ERROR_DOMAIN_MEMORY,
111	0	LIBCERROR_MEMORY_ERROR_SET_FAILED,
112	0	"%s: unable to clear Huffman tree.",
113	0	function );
114
115	0	memory_free(
116	0	*huffman_tree );
117
118	0	*huffman_tree = NULL;
119
120	0	return( -1 );
121	0	}
122	15.5k	array_size = sizeof( uint16_t ) * number_of_symbols;
123
124	15.5k	( huffman_tree )->symbols = (uint16_t ) memory_allocate(
125	15.5k	array_size );
126
127	15.5k	if( ( *huffman_tree )->symbols == NULL )
128	0	{
129	0	libcerror_error_set(
130	0	error,
131	0	LIBCERROR_ERROR_DOMAIN_MEMORY,
132	0	LIBCERROR_MEMORY_ERROR_INSUFFICIENT,
133	0	"%s: unable to create symbols.",
134	0	function );
135
136	0	goto on_error;
137	0	}
138	15.5k	if( memory_set(
139	15.5k	( *huffman_tree )->symbols,
140	15.5k	0,
141	15.5k	array_size ) == NULL )
142	0	{
143	0	libcerror_error_set(
144	0	error,
145	0	LIBCERROR_ERROR_DOMAIN_MEMORY,
146	0	LIBCERROR_MEMORY_ERROR_SET_FAILED,
147	0	"%s: unable to clear symbols.",
148	0	function );
149
150	0	goto on_error;
151	0	}
152	15.5k	array_size = sizeof( int ) * ( maximum_code_size + 1 );
153
154	15.5k	( huffman_tree )->code_size_counts = (int ) memory_allocate(
155	15.5k	array_size );
156
157	15.5k	if( ( *huffman_tree )->code_size_counts == NULL )
158	0	{
159	0	libcerror_error_set(
160	0	error,
161	0	LIBCERROR_ERROR_DOMAIN_MEMORY,
162	0	LIBCERROR_MEMORY_ERROR_INSUFFICIENT,
163	0	"%s: unable to create code size counts.",
164	0	function );
165
166	0	goto on_error;
167	0	}
168	15.5k	if( memory_set(
169	15.5k	( *huffman_tree )->code_size_counts,
170	15.5k	0,
171	15.5k	array_size ) == NULL )
172	0	{
173	0	libcerror_error_set(
174	0	error,
175	0	LIBCERROR_ERROR_DOMAIN_MEMORY,
176	0	LIBCERROR_MEMORY_ERROR_SET_FAILED,
177	0	"%s: unable to clear code size counts.",
178	0	function );
179
180	0	goto on_error;
181	0	}
182	15.5k	( *huffman_tree )->maximum_code_size = maximum_code_size;
183
184	15.5k	return( 1 );
185
186	0	on_error:
187	0	if( *huffman_tree != NULL )
188	0	{
189	0	if( ( *huffman_tree )->code_size_counts != NULL )
190	0	{
191	0	memory_free(
192	0	( *huffman_tree )->code_size_counts );
193	0	}
194	0	if( ( *huffman_tree )->symbols != NULL )
195	0	{
196	0	memory_free(
197	0	( *huffman_tree )->symbols );
198	0	}
199	0	memory_free(
200	0	*huffman_tree );
201
202	0	*huffman_tree = NULL;
203	0	}
204	0	return( -1 );
205	15.5k	}
206
207		/* Frees a Huffman tree
208		* Returns 1 if successful or -1 on error
209		*/
210		int libewf_huffman_tree_free(
211		libewf_huffman_tree_t **huffman_tree,
212		libcerror_error_t **error )
213	15.5k	{
214	15.5k	static char *function = "libewf_huffman_tree_free";
215
216	15.5k	if( huffman_tree == NULL )
217	0	{
218	0	libcerror_error_set(
219	0	error,
220	0	LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
221	0	LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
222	0	"%s: invalid Huffman tree.",
223	0	function );
224
225	0	return( -1 );
226	0	}
227	15.5k	if( *huffman_tree != NULL )
228	15.5k	{
229	15.5k	if( ( *huffman_tree )->code_size_counts != NULL )
230	15.5k	{
231	15.5k	memory_free(
232	15.5k	( *huffman_tree )->code_size_counts );
233	15.5k	}
234	15.5k	if( ( *huffman_tree )->symbols != NULL )
235	15.5k	{
236	15.5k	memory_free(
237	15.5k	( *huffman_tree )->symbols );
238	15.5k	}
239	15.5k	memory_free(
240	15.5k	*huffman_tree );
241
242	15.5k	*huffman_tree = NULL;
243	15.5k	}
244	15.5k	return( 1 );
245	15.5k	}
246
247		/* Builds the Huffman tree
248		* Returns 1 on success, 0 if the tree is empty or -1 on error
249		*/
250		int libewf_huffman_tree_build(
251		libewf_huffman_tree_t *huffman_tree,
252		const uint8_t *code_sizes_array,
253		int number_of_code_sizes,
254		libcerror_error_t **error )
255	15.4k	{
256	15.4k	int *symbol_offsets = NULL;
257	15.4k	static char *function = "libewf_huffman_tree_build";
258	15.4k	size_t array_size = 0;
259	15.4k	uint16_t symbol = 0;
260	15.4k	uint8_t bit_index = 0;
261	15.4k	uint8_t code_size = 0;
262	15.4k	int code_offset = 0;
263	15.4k	int left_value = 0;
264
265	15.4k	if( huffman_tree == NULL )
266	0	{
267	0	libcerror_error_set(
268	0	error,
269	0	LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
270	0	LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
271	0	"%s: invalid Huffman tree.",
272	0	function );
273
274	0	return( -1 );
275	0	}
276	15.4k	if( code_sizes_array == NULL )
277	0	{
278	0	libcerror_error_set(
279	0	error,
280	0	LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
281	0	LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
282	0	"%s: invalid code sizes array.",
283	0	function );
284
285	0	return( -1 );
286	0	}
287	15.4k	if( ( number_of_code_sizes < 0 )
288	15.4k	\|\| ( number_of_code_sizes > (int) INT16_MAX ) )
289	0	{
290	0	libcerror_error_set(
291	0	error,
292	0	LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
293	0	LIBCERROR_ARGUMENT_ERROR_VALUE_OUT_OF_BOUNDS,
294	0	"%s: invalid number of code sizes value out of bounds.",
295	0	function );
296
297	0	return( -1 );
298	0	}
299		/* Determine the code size frequencies
300		*/
301	15.4k	array_size = sizeof( int ) * ( huffman_tree->maximum_code_size + 1 );
302
303	15.4k	if( memory_set(
304	15.4k	huffman_tree->code_size_counts,
305	15.4k	0,
306	15.4k	array_size ) == NULL )
307	0	{
308	0	libcerror_error_set(
309	0	error,
310	0	LIBCERROR_ERROR_DOMAIN_MEMORY,
311	0	LIBCERROR_MEMORY_ERROR_SET_FAILED,
312	0	"%s: unable to clear code size counts.",
313	0	function );
314
315	0	goto on_error;
316	0	}
317	15.4k	for( symbol = 0;
318	1.62M	symbol < (uint16_t) number_of_code_sizes;
319	1.60M	symbol++ )
320	1.60M	{
321	1.60M	code_size = code_sizes_array[ symbol ];
322
323	1.60M	if( code_size > huffman_tree->maximum_code_size )
324	0	{
325	0	libcerror_error_set(
326	0	error,
327	0	LIBCERROR_ERROR_DOMAIN_RUNTIME,
328	0	LIBCERROR_RUNTIME_ERROR_VALUE_OUT_OF_BOUNDS,
329	0	"%s: invalid symbol: %d code size: %" PRIu8 " value out of bounds.",
330	0	function,
331	0	symbol,
332	0	code_size );
333
334	0	goto on_error;
335	0	}
336	1.60M	huffman_tree->code_size_counts[ code_size ] += 1;
337	1.60M	}
338		/* The tree has no codes
339		*/
340	15.4k	if( huffman_tree->code_size_counts[ 0 ] == number_of_code_sizes )
341	4	{
342	4	return( 0 );
343	4	}
344		/* Check if the set of code sizes is incomplete or over-subscribed
345		*/
346	15.4k	left_value = 1;
347
348	15.4k	for( bit_index = 1;
349	246k	bit_index <= huffman_tree->maximum_code_size;
350	230k	bit_index++ )
351	230k	{
352	230k	left_value <<= 1;
353	230k	left_value -= huffman_tree->code_size_counts[ bit_index ];
354
355	230k	if( left_value < 0 )
356	24	{
357	24	libcerror_error_set(
358	24	error,
359	24	LIBCERROR_ERROR_DOMAIN_RUNTIME,
360	24	LIBCERROR_RUNTIME_ERROR_VALUE_OUT_OF_BOUNDS,
361	24	"%s: code sizes are over-subscribed.",
362	24	function );
363
364	24	goto on_error;
365	24	}
366	230k	}
367		/* TODO
368		if( left_value > 0 )
369		{
370		libcerror_error_set(
371		error,
372		LIBCERROR_ERROR_DOMAIN_RUNTIME,
373		LIBCERROR_RUNTIME_ERROR_VALUE_OUT_OF_BOUNDS,
374		"%s: code sizes are incomplete.",
375		function );
376
377		goto on_error;
378		}
379		*/
380	15.3k	symbol_offsets = (int *) memory_allocate(
381	15.3k	array_size );
382
383	15.3k	if( symbol_offsets == NULL )
384	0	{
385	0	libcerror_error_set(
386	0	error,
387	0	LIBCERROR_ERROR_DOMAIN_MEMORY,
388	0	LIBCERROR_MEMORY_ERROR_INSUFFICIENT,
389	0	"%s: unable to create symbol offsets.",
390	0	function );
391
392	0	goto on_error;
393	0	}
394		/* Calculate the offsets to sort the symbols per code size
395		*/
396	15.3k	symbol_offsets[ 0 ] = 0;
397	15.3k	symbol_offsets[ 1 ] = 0;
398
399	15.3k	for( bit_index = 1;
400	230k	bit_index < huffman_tree->maximum_code_size;
401	215k	bit_index++ )
402	215k	{
403	215k	symbol_offsets[ bit_index + 1 ] = symbol_offsets[ bit_index ] + huffman_tree->code_size_counts[ bit_index ];
404	215k	}
405		/* Fill the symbols sorted by code size
406		*/
407	15.3k	for( symbol = 0;
408	1.61M	symbol < (uint16_t) number_of_code_sizes;
409	1.60M	symbol++ )
410	1.60M	{
411	1.60M	code_size = code_sizes_array[ symbol ];
412
413	1.60M	if( code_size == 0 )
414	1.17M	{
415	1.17M	continue;
416	1.17M	}
417	431k	code_offset = symbol_offsets[ code_size ];
418
419	431k	if( ( code_offset < 0 )
420	431k	\|\| ( code_offset > number_of_code_sizes ) )
421	0	{
422	0	libcerror_error_set(
423	0	error,
424	0	LIBCERROR_ERROR_DOMAIN_RUNTIME,
425	0	LIBCERROR_RUNTIME_ERROR_VALUE_OUT_OF_BOUNDS,
426	0	"%s: invalid symbol: %" PRIu16 " code offset: %d value out of bounds.",
427	0	function,
428	0	symbol,
429	0	code_offset );
430
431	0	goto on_error;
432	0	}
433	431k	symbol_offsets[ code_size ] += 1;
434
435	431k	huffman_tree->symbols[ code_offset ] = symbol;
436	431k	}
437	15.3k	memory_free(
438	15.3k	symbol_offsets );
439
440	15.3k	return( 1 );
441
442	24	on_error:
443	24	if( symbol_offsets != NULL )
444	0	{
445	0	memory_free(
446	0	symbol_offsets );
447	0	}
448	24	return( -1 );
449	15.3k	}
450
451		/* Retrieves a symbol based on the Huffman code read from the bit-stream
452		* Returns 1 on success or -1 on error
453		*/
454		int libewf_huffman_tree_get_symbol_from_bit_stream(
455		libewf_huffman_tree_t *huffman_tree,
456		libewf_bit_stream_t *bit_stream,
457		uint16_t *symbol,
458		libcerror_error_t **error )
459	18.3M	{
460	18.3M	static char *function = "libewf_huffman_tree_get_symbol_from_bit_stream";
461	18.3M	uint32_t value_32bit = 0;
462	18.3M	uint16_t safe_symbol = 0;
463	18.3M	uint8_t bit_index = 0;
464	18.3M	int code_size_count = 0;
465	18.3M	int first_huffman_code = 0;
466	18.3M	int first_index = 0;
467	18.3M	int huffman_code = 0;
468	18.3M	int result = 0;
469
470	18.3M	if( huffman_tree == NULL )
471	0	{
472	0	libcerror_error_set(
473	0	error,
474	0	LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
475	0	LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
476	0	"%s: invalid Huffman tree.",
477	0	function );
478
479	0	return( -1 );
480	0	}
481	18.3M	if( bit_stream == NULL )
482	0	{
483	0	libcerror_error_set(
484	0	error,
485	0	LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
486	0	LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
487	0	"%s: invalid bit stream.",
488	0	function );
489
490	0	return( -1 );
491	0	}
492	18.3M	if( symbol == NULL )
493	0	{
494	0	libcerror_error_set(
495	0	error,
496	0	LIBCERROR_ERROR_DOMAIN_ARGUMENTS,
497	0	LIBCERROR_ARGUMENT_ERROR_INVALID_VALUE,
498	0	"%s: invalid symbol.",
499	0	function );
500
501	0	return( -1 );
502	0	}
503		/* TODO get maximum_code_size of bits into local bit buffer */
504
505	18.3M	for( bit_index = 1;
506	48.2M	bit_index <= huffman_tree->maximum_code_size;
507	29.9M	bit_index++ )
508	48.2M	{
509	48.2M	if( libewf_bit_stream_get_value(
510	48.2M	bit_stream,
511	48.2M	1,
512	48.2M	&value_32bit,
513	48.2M	error ) != 1 )
514	12	{
515	12	libcerror_error_set(
516	12	error,
517	12	LIBCERROR_ERROR_DOMAIN_RUNTIME,
518	12	LIBCERROR_RUNTIME_ERROR_GET_FAILED,
519	12	"%s: unable to retrieve value from bit stream.",
520	12	function );
521
522	12	return( -1 );
523	12	}
524	48.2M	huffman_code <<= 1;
525	48.2M	huffman_code \|= (int) value_32bit;
526
527	48.2M	code_size_count = huffman_tree->code_size_counts[ bit_index ];
528
529	48.2M	if( ( huffman_code - code_size_count ) < first_huffman_code )
530	18.3M	{
531	18.3M	safe_symbol = huffman_tree->symbols[ first_index + ( huffman_code - first_huffman_code ) ];
532
533	18.3M	result = 1;
534
535	18.3M	break;
536	18.3M	}
537	29.9M	first_huffman_code += code_size_count;
538	29.9M	first_huffman_code <<= 1;
539	29.9M	first_index += code_size_count;
540	29.9M	}
541	18.3M	if( result != 1 )
542	19	{
543	19	libcerror_error_set(
544	19	error,
545	19	LIBCERROR_ERROR_DOMAIN_RUNTIME,
546	19	LIBCERROR_RUNTIME_ERROR_VALUE_OUT_OF_BOUNDS,
547	19	"%s: invalid Huffman code: 0x%08" PRIx32 ".",
548	19	function,
549	19	huffman_code );
550
551	19	return( -1 );
552	19	}
553	18.3M	*symbol = safe_symbol;
554
555	18.3M	return( 1 );
556	18.3M	}
557