private void InitializeBytes()
{
if (_bytes != null)
{
return;
}
uint fetched = 0;
_bytes = new byte[0];
IDebugMemoryContext2 memAddr;
if (GetMemoryContext(out memAddr) != VSConstants.S_OK)
{
// no address in the expression value, try casting to a char*
VariableInformation v = new VariableInformation("(char*)(" + _variableInformation.FullName() + ")", (VariableInformation)_variableInformation);
v.SyncEval();
if (v.Error)
{
return;
}
AD7Property p = new AD7Property(_engine, v);
uint pLen;
if (p.GetStringCharLength(out pLen) == VSConstants.S_OK)
{
_bytes = new byte[pLen];
p.GetStringRawBytes(pLen, _bytes, out fetched);
}
return;
}
IDebugMemoryBytes2 memContent;
if (((AD7MemoryAddress)memAddr).Engine.GetMemoryBytes(out memContent) != VSConstants.S_OK)
{
return;
}
fetched = 0;
bool eos = false;
byte[] bytes = new byte[s_maxChars + 1];
byte[] chunk = new byte[2048];
while (!eos)
{
// fetched is count of bytes in string so far
// eos == false => fetch < s_maxChars
// eos == true => string is terminated, that is bytes[fetched-1] == 0
uint bytesRead;
uint bytesUnreadable = 0;
// get next chunk
if (memContent.ReadAt(memAddr, (uint)chunk.Length, chunk, out bytesRead, ref bytesUnreadable) != VSConstants.S_OK)
{
break;
}
// copy chunk to bytes
for (uint i = 0; i < bytesRead; ++i)
{
bytes[fetched++] = chunk[i];
if (bytes[fetched - 1] == 0)
{
eos = true; // end of string
break;
}
if (fetched == s_maxChars) // buffer is full
{
bytes[fetched++] = 0; // end the string
eos = true;
break;
}
}
if (bytesRead != chunk.Length)
{
// read to end of available memory
break;
}
// advance to next chunk
memAddr.Add(bytesRead, out memAddr);
}
if (!eos)
{
Debug.Assert(fetched < bytes.Length);
bytes[fetched++] = 0;
}
if (fetched < bytes.Length)
{
_bytes = new byte[fetched];
Array.Copy(bytes, _bytes, (int)fetched);
}
else
{
_bytes = bytes;
}
}