1 ///////////////////////////////////////////////////////////////////////////////
2 //
3 /// \file       filter_flags_decoder.c
4 /// \brief      Decodes a Filter Flags field
5 //
6 //  Author:     Lasse Collin
7 //
8 //  This file has been put into the public domain.
9 //  You can do whatever you want with this file.
10 //
11 ///////////////////////////////////////////////////////////////////////////////
12 
13 #include "filter_decoder.h"
14 
15 
16 extern LZMA_API(lzma_ret)
17 lzma_filter_flags_decode(
18 		lzma_filter *filter, const lzma_allocator *allocator,
19 		const uint8_t *in, size_t *in_pos, size_t in_size)
20 {
21 	// Set the pointer to NULL so the caller can always safely free it.
22 	filter->options = NULL;
23 
24 	// Filter ID
25 	return_if_error(lzma_vli_decode(&filter->id, NULL,
26 			in, in_pos, in_size));
27 
28 	if (filter->id >= LZMA_FILTER_RESERVED_START)
29 		return LZMA_DATA_ERROR;
30 
31 	// Size of Properties
32 	lzma_vli props_size;
33 	return_if_error(lzma_vli_decode(&props_size, NULL,
34 			in, in_pos, in_size));
35 
36 	// Filter Properties
37 	if (in_size - *in_pos < props_size)
38 		return LZMA_DATA_ERROR;
39 
40 	const lzma_ret ret = lzma_properties_decode(
41 			filter, allocator, in + *in_pos, props_size);
42 
43 	*in_pos += props_size;
44 
45 	return ret;
46 }
47