src/mpeg2/ts/PMT.cpp

   1 /*
   2  *  PMT.cpp
   3  */
   4
   5 #include "mpeg2/ts/PMT.h"
   6
   7 namespace MPEG2
   8 {
   9 namespace TS
  10 {
  11
  12 PMT::PMT()
  13 {
  14     _descriptor = NULL;
  15     _element_count = 0;
  16     _elements = NULL;
  17 }
  18
  19 PMT::~PMT()
  20 {
  21     if (_descriptor != NULL)
  22     {
  23         free(_descriptor);
  24     }
  25     if (_elements != NULL)
  26     {
  27         for (int i = 0; i < _element_count; ++i)
  28         {
  29             if (_elements[i]._descriptor != NULL)
  30             {
  31                 free(_elements[i]._descriptor);
  32             }
  33         }
  34         free(_elements);
  35     }
  36 }
  37
  38 bool PMT::decode_section()
  39 {
  40     bool result = true;
  41     _table_id                 = _section[0x00];
  42     if (_table_id == TABLE_ID_PMT)
  43     {
  44         _section_syntax_indicator = (_section[0x01] & 0x80) >> 7;
  45         _section_length           = ((_section[0x01] << 8) + _section[0x02]) & 0x0FFF;
  46         _program_number           = (_section[0x03] << 8) + _section[0x04];
  47         _version_number           = (_section[0x05] & 0x3E) >> 1;
  48         _current_next_indicator   = _section[0x05] & 0x01;
  49         _section_number           = _section[0x06];
  50         _last_section_number      = _section[0x07];
  51         _PCR_PID                  = ((_section[0x08] << 8) + _section[0x09]) & 0x1FFF;
  52         _program_info_length      = ((_section[0x0a] << 8) + _section[0x0b]) & 0x0FFF;
  53         if (_descriptor != NULL)
  54         {
  55             free(_descriptor);
  56         }
  57         _descriptor               = (uint8_t *)malloc(_program_info_length);
  58         memcpy(_descriptor, &_section[0x0c], _program_info_length);
  59
  60         if (_elements != NULL)
  61         {
  62             for (int i = 0; i < _element_count; ++i)
  63             {
  64                 if (_elements[i]._descriptor != NULL)
  65                 {
  66                     free(_elements[i]._descriptor);
  67                 }
  68             }
  69             free(_elements);
  70             _elements = NULL;
  71         }
  72
  73         uint16_t offset = 0x0c + _program_info_length;
  74
  75         _element_count = 0;
  76         while (offset < (_length - 4))
  77         {
  78             if (_elements == NULL)
  79             {
  80                 _elements = (struct _element *)malloc(sizeof(struct _element));
  81             }
  82             else
  83             {
  84                 _elements = (struct _element *)realloc(_elements, sizeof(struct _element) * (_element_count + 1));
  85             }
  86             _elements[_element_count]._stream_type = _section[offset];
  87             _elements[_element_count]._elementary_PID = ((_section[offset + 1] << 8) + _section[offset + 2]) & 0x1FFF;
  88             _elements[_element_count]._ES_info_length = ((_section[offset + 3] << 8) + _section[offset + 4]) & 0x0FFF;
  89             _elements[_element_count]._descriptor = (uint8_t *)malloc(_elements[_element_count]._ES_info_length);
  90             memcpy(_elements[_element_count]._descriptor, &_section[offset + 5], _elements[_element_count]._ES_info_length);
  91             offset += (5 + _elements[_element_count]._ES_info_length);
  92             _element_count++;
  93         }
  94     }
  95     else
  96     {
  97         reset();
  98         result = false;
  99     }
 100
 101     return result;
 102 }
 103
 104 void PMT::reset()
 105 {
 106     _section_syntax_indicator = 0;
 107     _section_length           = 0;
 108     _program_number           = 0;
 109     _version_number           = 0;
 110     _current_next_indicator   = 0;
 111     _section_number           = 0;
 112     _last_section_number      = 0;
 113     _PCR_PID                  = 0;
 114     _program_info_length      = 0;
 115     if (_descriptor != NULL)
 116     {
 117         free(_descriptor);
 118         _descriptor = NULL;
 119     }
 120     if (_elements != NULL)
 121     {
 122         for (int i = 0; i < _element_count; ++i)
 123         {
 124             if (_elements[i]._descriptor != NULL)
 125             {
 126                 free(_elements[i]._descriptor);
 127             }
 128         }
 129         free(_elements);
 130         _elements = NULL;
 131         _element_count = 0;
 132     }
 133 }
 134
 135 } // TS
 136 } // MPEG2