common/TLVHelper.cpp

   1 /*
   2  * Copyright (c) 2012, 2013 Samsung Electronics Co., Ltd.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 /* standard library header */
  18 #include <stdio.h>
  19 #include <string.h>
  20
  21 /* SLP library header */
  22
  23 /* local header */
  24 #include "Debug.h"
  25 #include "TLVHelper.h"
  26
  27 namespace smartcard_service_api
  28 {
  29         void TLVHelper::initialize(TLVHelper *parent)
  30         {
  31                 parentTLV = parent;
  32                 childTLV = NULL;
  33                 currentTLV = this;
  34                 offset = 0;
  35                 currentT = 0;
  36                 currentL = 0;
  37         }
  38
  39         TLVHelper::TLVHelper()
  40         {
  41                 initialize();
  42         }
  43
  44         TLVHelper::TLVHelper(TLVHelper *parent)
  45         {
  46                 initialize(parent);
  47         }
  48
  49         TLVHelper::TLVHelper(const ByteArray &array)
  50         {
  51                 setTLVBuffer(array);
  52         }
  53
  54         TLVHelper::TLVHelper(const ByteArray &array, TLVHelper *parent)
  55         {
  56                 setTLVBuffer(array, parent);
  57         }
  58
  59         TLVHelper::~TLVHelper()
  60         {
  61         }
  62
  63         bool TLVHelper::setTLVBuffer(const ByteArray &array, TLVHelper *parent)
  64         {
  65                 initialize(parent);
  66
  67                 if (array.getLength() == 0)
  68                         return false;
  69
  70                 tlvBuffer = array;
  71
  72                 return true;
  73         }
  74
  75         bool TLVHelper::setTLVBuffer(unsigned char *buffer, unsigned int length, TLVHelper *parent)
  76         {
  77                 return setTLVBuffer(ByteArray(buffer, length), parent);
  78         }
  79
  80         bool TLVHelper::_decodeTLV()
  81         {
  82                 int result;
  83
  84                 currentT = 0;
  85                 currentL = 0;
  86                 currentV.releaseBuffer();
  87
  88                 if (isEndOfBuffer())
  89                         return false;
  90
  91                 /* T */
  92                 if ((result = decodeTag(tlvBuffer.getBuffer(offset))) < 0)
  93                         return false;
  94
  95                 offset += result;
  96
  97                 /* L */
  98                 if ((result = decodeLength(tlvBuffer.getBuffer(offset))) < 0)
  99                         return false;
 100
 101                 offset += result;
 102
 103                 if (currentL > 0)
 104                 {
 105                         /* V */
 106                         if ((result = decodeValue(tlvBuffer.getBuffer(offset))) < 0)
 107                                 return false;
 108
 109                         offset += result;
 110                 }
 111
 112                 return true;
 113         }
 114
 115         const char *TLVHelper::toString()
 116         {
 117                 memset(strBuffer, 0, sizeof(strBuffer));
 118
 119                 if (currentL == 0)
 120                 {
 121                         snprintf(strBuffer, sizeof(strBuffer), "T [%X], L [%d]", getTag(), getLength());
 122                 }
 123                 else
 124                 {
 125                         snprintf(strBuffer, sizeof(strBuffer), "T [%X], L [%d], V %s", getTag(), getLength(), getValue().toString());
 126                 }
 127
 128                 return strBuffer;
 129         }
 130
 131         TLVHelper *TLVHelper::getParentTLV()
 132         {
 133                 return parentTLV;
 134         }
 135
 136         bool TLVHelper::enterToValueTLV()
 137         {
 138                 bool result = false;
 139                 TLVHelper *temp = NULL;
 140
 141                 if (getLength() >= 2)
 142                 {
 143                         temp = currentTLV->getChildTLV(getValue());
 144
 145                         if (temp != NULL)
 146                         {
 147                                 currentTLV = temp;
 148                                 result = true;
 149                         }
 150                 }
 151
 152                 return result;
 153         }
 154
 155         bool TLVHelper::returnToParentTLV()
 156         {
 157                 bool result = true;
 158
 159 //              SCARD_DEBUG("current [%p], parent [%p]", currentTLV, currentTLV->getParentTLV());
 160
 161                 if (currentTLV->getParentTLV() != NULL)
 162                 {
 163                         currentTLV = currentTLV->getParentTLV();
 164                 }
 165                 else
 166                 {
 167                         /* top tlv */
 168                 }
 169
 170                 return result;
 171         }
 172
 173 } /* namespace smartcard_service_api */