release/src-rt-6.x.4708/tools/misc/xz/src/liblzma/common/filter_flags_decoder.c

   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, 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 }