source/bzip2.cpp

   1 #include <ail/bzip2.hpp>
   2
   3 namespace ail
   4 {
   5         bzip2_reader::bzip2_reader():
   6                 bz_file(0)
   7         {
   8         }
   9
  10         bzip2_reader::bzip2_reader(std::string const & file_name)
  11         {
  12                 open(file_name);
  13         }
  14
  15         bzip2_reader::~bzip2_reader()
  16         {
  17                 if(bz_file != 0)
  18                 {
  19                         int bz_error;
  20                         ::fclose(file);
  21                         ::BZ2_bzReadClose(&bz_error, bz_file);
  22                 }
  23         }
  24
  25         bool bzip2_reader::open(std::string const & file_name)
  26         {
  27                 int bz_error;
  28                 file = ::fopen(file_name.c_str(), "rb");
  29                 if(file == 0)
  30                         return false;
  31                 bz_file = ::BZ2_bzReadOpen(&bz_error, file, 0, 0, 0, 0);
  32                 if(bz_file == 0)
  33                 {
  34                         ::fclose(file);
  35                         ::BZ2_bzReadClose(&bz_error, bz_file);
  36                         return false;
  37                 }
  38                 return true;
  39         }
  40
  41         bool bzip2_reader::read(std::string & buffer)
  42         {
  43                 std::size_t const buffer_size = 16 * 1024;
  44                 char in_buffer[buffer_size];
  45                 int bz_error;
  46                 int bytes_read = ::BZ2_bzRead(&bz_error, bz_file, in_buffer, static_cast<int>(buffer_size));
  47                 if(bz_error != BZ_OK)
  48                         return false;
  49                 std::string new_data;
  50                 new_data.assign(in_buffer, static_cast<std::size_t>(bytes_read));
  51                 buffer += new_data;
  52                 return true;
  53         }
  54
  55         bool decompress_bzip2(std::string const & file_name, std::string & output)
  56         {
  57                 bzip2_reader reader;
  58                 if(!reader.open(file_name))
  59                         return false;
  60                 while(reader.read(output));
  61                 return true;
  62         }
  63 }