+// ----------------------------------------------------------------------------
+// constants
+// ----------------------------------------------------------------------------
+
+// the temporary buffer size used when copying from stream to stream
+#define BUF_TEMP_SIZE 4096
+
+// ============================================================================
+// implementation
+// ============================================================================
+
+// ----------------------------------------------------------------------------
+// wxStreamBuffer
+// ----------------------------------------------------------------------------
+
+void wxStreamBuffer::SetError(wxStreamError err)
+{
+ if ( m_stream && m_stream->m_lasterror == wxSTREAM_NO_ERROR )
+ m_stream->m_lasterror = err;
+}
+
+void wxStreamBuffer::InitBuffer()
+{
+ m_buffer_start =
+ m_buffer_end =
+ m_buffer_pos = NULL;
+ m_buffer_size = 0;
+
+ // if we are going to allocate the buffer, we should free it later as well
+ m_destroybuf = true;
+}
+
+void wxStreamBuffer::Init()
+{
+ InitBuffer();
+
+ m_fixed = true;
+}
+
+wxStreamBuffer::wxStreamBuffer(BufMode mode)
+{
+ Init();
+
+ m_stream = NULL;
+ m_mode = mode;
+
+ m_flushable = false;
+}
+
+wxStreamBuffer::wxStreamBuffer(wxStreamBase& stream, BufMode mode)
+{
+ Init();
+
+ m_stream = &stream;
+ m_mode = mode;
+
+ m_flushable = true;
+}
+
+wxStreamBuffer::wxStreamBuffer(const wxStreamBuffer& buffer)
+{
+ // doing this has big chances to lead to a crash when the source buffer is
+ // destroyed (otherwise assume the caller knows what he does)
+ wxASSERT_MSG( !buffer.m_destroybuf,
+ _T("it's a bad idea to copy this buffer") );
+
+ m_buffer_start = buffer.m_buffer_start;
+ m_buffer_end = buffer.m_buffer_end;
+ m_buffer_pos = buffer.m_buffer_pos;
+ m_buffer_size = buffer.m_buffer_size;
+ m_fixed = buffer.m_fixed;
+ m_flushable = buffer.m_flushable;
+ m_stream = buffer.m_stream;
+ m_mode = buffer.m_mode;
+ m_destroybuf = false;
+}
+
+void wxStreamBuffer::FreeBuffer()
+{
+ if ( m_destroybuf )
+ {
+ free(m_buffer_start);
+ m_buffer_start = NULL;
+ }
+}
+
+wxStreamBuffer::~wxStreamBuffer()
+{
+ FreeBuffer();
+}
+
+wxInputStream *wxStreamBuffer::GetInputStream() const
+{
+ return m_mode == write ? NULL : (wxInputStream *)m_stream;
+}
+
+wxOutputStream *wxStreamBuffer::GetOutputStream() const
+{
+ return m_mode == read ? NULL : (wxOutputStream *)m_stream;
+}
+
+void wxStreamBuffer::SetBufferIO(void *buffer_start,
+ void *buffer_end,
+ bool takeOwnership)
+{
+ SetBufferIO(buffer_start, (char *)buffer_end - (char *)buffer_start,
+ takeOwnership);
+}
+
+void wxStreamBuffer::SetBufferIO(void *start,
+ size_t len,
+ bool takeOwnership)
+{
+ // start by freeing the old buffer
+ FreeBuffer();
+
+ m_buffer_start = (char *)start;
+ m_buffer_end = m_buffer_start + len;
+
+ m_buffer_size = len;
+
+ // if we own it, we free it
+ m_destroybuf = takeOwnership;
+
+ ResetBuffer();
+}
+
+void wxStreamBuffer::SetBufferIO(size_t bufsize)
+{
+ if ( bufsize )
+ {
+ // this will free the old buffer and allocate the new one
+ SetBufferIO(malloc(bufsize), bufsize, true /* take ownership */);
+ }
+ else // no buffer size => no buffer
+ {
+ // still free the old one
+ FreeBuffer();
+ InitBuffer();
+ }
+}
+
+void wxStreamBuffer::ResetBuffer()
+{
+ if ( m_stream )
+ {
+ m_stream->Reset();
+ m_stream->m_lastcount = 0;
+ }
+
+ m_buffer_pos = m_mode == read && m_flushable
+ ? m_buffer_end
+ : m_buffer_start;
+}
+
+// fill the buffer with as much data as possible (only for read buffers)
+bool wxStreamBuffer::FillBuffer()
+{
+ wxInputStream *inStream = GetInputStream();
+
+ // It's legal to have no stream, so we don't complain about it just return false
+ if ( !inStream )
+ return false;
+
+ size_t count = inStream->OnSysRead(m_buffer_start, m_buffer_size);
+ if ( !count )
+ return false;
+
+ m_buffer_end = m_buffer_start + count;
+ m_buffer_pos = m_buffer_start;
+
+ return true;
+}
+
+// write the buffer contents to the stream (only for write buffers)
+bool wxStreamBuffer::FlushBuffer()
+{
+ wxCHECK_MSG( m_flushable, false, _T("can't flush this buffer") );
+
+ // FIXME: what is this check for? (VZ)
+ if ( m_buffer_pos == m_buffer_start )
+ return false;
+
+ wxOutputStream *outStream = GetOutputStream();
+
+ wxCHECK_MSG( outStream, false, _T("should have a stream in wxStreamBuffer") );
+
+ size_t current = m_buffer_pos - m_buffer_start;
+ size_t count = outStream->OnSysWrite(m_buffer_start, current);
+ if ( count != current )
+ return false;
+
+ m_buffer_pos = m_buffer_start;
+
+ return true;
+}
+
+size_t wxStreamBuffer::GetDataLeft()
+{
+ /* Why is this done? RR. */
+ if ( m_buffer_pos == m_buffer_end && m_flushable)
+ FillBuffer();
+
+ return GetBytesLeft();
+}
+
+// copy up to size bytes from our buffer into the provided one
+void wxStreamBuffer::GetFromBuffer(void *buffer, size_t size)
+{
+ // don't get more bytes than left in the buffer
+ size_t left = GetBytesLeft();
+
+ if ( size > left )
+ size = left;
+
+ memcpy(buffer, m_buffer_pos, size);
+ m_buffer_pos += size;
+}
+
+// copy the contents of the provided buffer into this one
+void wxStreamBuffer::PutToBuffer(const void *buffer, size_t size)
+{
+ size_t left = GetBytesLeft();
+
+ if ( size > left )
+ {
+ if ( m_fixed )
+ {
+ // we can't realloc the buffer, so just copy what we can
+ size = left;
+ }
+ else // !m_fixed
+ {
+ // realloc the buffer to have enough space for the data
+ size_t delta = m_buffer_pos - m_buffer_start;
+
+ char *startOld = m_buffer_start;
+ m_buffer_size += size;
+ m_buffer_start = (char *)realloc(m_buffer_start, m_buffer_size);
+ if ( !m_buffer_start )
+ {
+ // don't leak memory if realloc() failed
+ m_buffer_start = startOld;
+ m_buffer_size -= size;
+
+ // what else can we do?
+ return;
+ }
+
+ // adjust the pointers invalidated by realloc()
+ m_buffer_pos = m_buffer_start + delta;
+ m_buffer_end = m_buffer_start + m_buffer_size;
+ }
+ }
+
+ memcpy(m_buffer_pos, buffer, size);
+ m_buffer_pos += size;
+}
+
+void wxStreamBuffer::PutChar(char c)
+{
+ wxOutputStream *outStream = GetOutputStream();
+
+ wxCHECK_RET( outStream, _T("should have a stream in wxStreamBuffer") );
+
+ // if we don't have buffer at all, just forward this call to the stream,
+ if ( !HasBuffer() )
+ {
+ outStream->OnSysWrite(&c, sizeof(c));
+ }
+ else
+ {
+ // otherwise check we have enough space left
+ if ( !GetDataLeft() && !FlushBuffer() )
+ {
+ // we don't
+ SetError(wxSTREAM_WRITE_ERROR);
+ }
+ else
+ {
+ PutToBuffer(&c, sizeof(c));
+ m_stream->m_lastcount = 1;
+ }
+ }
+}
+
+char wxStreamBuffer::Peek()
+{
+ wxCHECK_MSG( m_stream && HasBuffer(), 0,
+ _T("should have the stream and the buffer in wxStreamBuffer") );
+
+ if ( !GetDataLeft() )
+ {
+ SetError(wxSTREAM_READ_ERROR);
+ return 0;
+ }
+
+ char c;
+ GetFromBuffer(&c, sizeof(c));
+ m_buffer_pos--;
+
+ return c;
+}
+
+char wxStreamBuffer::GetChar()
+{
+ wxInputStream *inStream = GetInputStream();
+
+ wxCHECK_MSG( inStream, 0, _T("should have a stream in wxStreamBuffer") );
+
+ char c;
+ if ( !HasBuffer() )
+ {
+ inStream->OnSysRead(&c, sizeof(c));
+ }
+ else
+ {
+ if ( !GetDataLeft() )
+ {
+ SetError(wxSTREAM_READ_ERROR);
+ c = 0;
+ }
+ else
+ {
+ GetFromBuffer(&c, sizeof(c));
+ m_stream->m_lastcount = 1;
+ }
+ }
+
+ return c;
+}
+
+size_t wxStreamBuffer::Read(void *buffer, size_t size)
+{
+ // lasterror is reset before all new IO calls
+ if ( m_stream )
+ m_stream->Reset();
+
+ size_t readBytes;
+ if ( !HasBuffer() )
+ {
+ wxInputStream *inStream = GetInputStream();
+
+ wxCHECK_MSG( inStream, 0, _T("should have a stream in wxStreamBuffer") );
+
+ readBytes = inStream->OnSysRead(buffer, size);
+ }
+ else // we have a buffer, use it
+ {
+ size_t orig_size = size;
+
+ while ( size > 0 )
+ {
+ size_t left = GetDataLeft();
+
+ // if the requested number of bytes if greater than the buffer
+ // size, read data in chunks
+ if ( size > left )
+ {
+ GetFromBuffer(buffer, left);
+ size -= left;
+ buffer = (char *)buffer + left;
+
+ if ( !FillBuffer() )
+ {
+ SetError(wxSTREAM_EOF);
+ break;
+ }
+ }
+ else // otherwise just do it in one gulp
+ {
+ GetFromBuffer(buffer, size);
+ size = 0;
+ }
+ }
+
+ readBytes = orig_size - size;
+ }
+
+ if ( m_stream )
+ m_stream->m_lastcount = readBytes;
+
+ return readBytes;
+}
+
+// this should really be called "Copy()"
+size_t wxStreamBuffer::Read(wxStreamBuffer *dbuf)
+{
+ wxCHECK_MSG( m_mode != write, 0, _T("can't read from this buffer") );
+
+ char buf[BUF_TEMP_SIZE];
+ size_t nRead,
+ total = 0;
+
+ do
+ {
+ nRead = Read(buf, WXSIZEOF(buf));
+ if ( nRead )
+ {
+ nRead = dbuf->Write(buf, nRead);
+ total += nRead;
+ }
+ }
+ while ( nRead );
+
+ return total;
+}
+
+size_t wxStreamBuffer::Write(const void *buffer, size_t size)
+{
+ if (m_stream)
+ {
+ // lasterror is reset before all new IO calls
+ m_stream->Reset();
+ }
+
+ size_t ret;
+
+ if ( !HasBuffer() && m_fixed )
+ {
+ wxOutputStream *outStream = GetOutputStream();
+
+ wxCHECK_MSG( outStream, 0, _T("should have a stream in wxStreamBuffer") );
+
+ // no buffer, just forward the call to the stream
+ ret = outStream->OnSysWrite(buffer, size);
+ }
+ else // we [may] have a buffer, use it
+ {
+ size_t orig_size = size;
+
+ while ( size > 0 )
+ {
+ size_t left = GetBytesLeft();
+
+ // if the buffer is too large to fit in the stream buffer, split
+ // it in smaller parts
+ //
+ // NB: If stream buffer isn't fixed (as for wxMemoryOutputStream),
+ // we always go to the second case.
+ //
+ // FIXME: fine, but if it fails we should (re)try writing it by
+ // chunks as this will (hopefully) always work (VZ)
+
+ if ( size > left && m_fixed )
+ {
+ PutToBuffer(buffer, left);
+ size -= left;
+ buffer = (char *)buffer + left;
+
+ if ( !FlushBuffer() )
+ {
+ SetError(wxSTREAM_WRITE_ERROR);
+
+ break;
+ }
+
+ m_buffer_pos = m_buffer_start;
+ }
+ else // we can do it in one gulp
+ {
+ PutToBuffer(buffer, size);
+ size = 0;
+ }
+ }
+
+ ret = orig_size - size;
+ }
+
+ if (m_stream)
+ {
+ // i am not entirely sure what we do this for
+ m_stream->m_lastcount = ret;
+ }
+
+ return ret;
+}
+
+size_t wxStreamBuffer::Write(wxStreamBuffer *sbuf)
+{
+ wxCHECK_MSG( m_mode != read, 0, _T("can't write to this buffer") );
+ wxCHECK_MSG( sbuf->m_mode != write, 0, _T("can't read from that buffer") );
+
+ char buf[BUF_TEMP_SIZE];
+ size_t nWrite,
+ total = 0;
+
+ do
+ {
+ size_t nRead = sbuf->Read(buf, WXSIZEOF(buf));
+ if ( nRead )
+ {
+ nWrite = Write(buf, nRead);
+ if ( nWrite < nRead )
+ {
+ // put back data we couldn't copy
+ wxInputStream *in_stream = (wxInputStream *)sbuf->GetStream();
+
+ in_stream->Ungetch(buf + nWrite, nRead - nWrite);
+ }
+
+ total += nWrite;
+ }
+ else
+ {
+ nWrite = 0;
+ }
+ }
+ while ( nWrite == WXSIZEOF(buf) );
+
+ return total;
+}
+
+wxFileOffset wxStreamBuffer::Seek(wxFileOffset pos, wxSeekMode mode)
+{
+ wxFileOffset ret_off, diff;
+
+ wxFileOffset last_access = GetLastAccess();
+
+ if ( !m_flushable )
+ {
+ switch (mode)
+ {
+ case wxFromStart:
+ diff = pos;
+ break;
+
+ case wxFromCurrent:
+ diff = pos + GetIntPosition();
+ break;
+
+ case wxFromEnd:
+ diff = pos + last_access;
+ break;
+
+ default:
+ wxFAIL_MSG( _T("invalid seek mode") );
+
+ return wxInvalidOffset;
+ }
+ if (diff < 0 || diff > last_access)
+ return wxInvalidOffset;
+ size_t int_diff = wx_truncate_cast(size_t, diff);
+ wxCHECK_MSG( (wxFileOffset)int_diff == diff, wxInvalidOffset, wxT("huge file not supported") );
+ SetIntPosition(int_diff);
+ return diff;
+ }
+
+ switch ( mode )
+ {
+ case wxFromStart:
+ // We'll try to compute an internal position later ...
+ ret_off = m_stream->OnSysSeek(pos, wxFromStart);
+ ResetBuffer();
+ return ret_off;
+
+ case wxFromCurrent:
+ diff = pos + GetIntPosition();
+
+ if ( (diff > last_access) || (diff < 0) )
+ {
+ // We must take into account the fact that we have read
+ // something previously.
+ ret_off = m_stream->OnSysSeek(diff-last_access, wxFromCurrent);
+ ResetBuffer();
+ return ret_off;
+ }
+ else
+ {
+ size_t int_diff = wx_truncate_cast(size_t, diff);
+ wxCHECK_MSG( (wxFileOffset)int_diff == diff, wxInvalidOffset, wxT("huge file not supported") );
+ SetIntPosition(int_diff);
+ return pos;
+ }
+
+ case wxFromEnd:
+ // Hard to compute: always seek to the requested position.
+ ret_off = m_stream->OnSysSeek(pos, wxFromEnd);
+ ResetBuffer();
+ return ret_off;
+ }
+
+ return wxInvalidOffset;
+}
+
+wxFileOffset wxStreamBuffer::Tell() const
+{
+ wxFileOffset pos;
+
+ // ask the stream for position if we have a real one
+ if ( m_stream )
+ {
+ pos = m_stream->OnSysTell();
+ if ( pos == wxInvalidOffset )
+ return wxInvalidOffset;
+ }
+ else // no associated stream
+ {
+ pos = 0;
+ }
+
+ pos += GetIntPosition();
+
+ if ( m_mode == read && m_flushable )
+ pos -= GetLastAccess();
+
+ return pos;
+}
+
+// ----------------------------------------------------------------------------
+// wxStreamBase
+// ----------------------------------------------------------------------------
+
+wxStreamBase::wxStreamBase()
+{
+ m_lasterror = wxSTREAM_NO_ERROR;
+ m_lastcount = 0;
+}
+
+wxStreamBase::~wxStreamBase()
+{
+}
+
+size_t wxStreamBase::GetSize() const
+{
+ wxFileOffset length = GetLength();
+ if ( length == wxInvalidOffset )
+ return 0;
+
+ const size_t len = wx_truncate_cast(size_t, length);
+ wxASSERT_MSG( len == length + size_t(0), _T("large files not supported") );
+
+ return len;
+}
+
+wxFileOffset wxStreamBase::OnSysSeek(wxFileOffset WXUNUSED(seek), wxSeekMode WXUNUSED(mode))
+{
+ return wxInvalidOffset;
+}
+
+wxFileOffset wxStreamBase::OnSysTell() const
+{
+ return wxInvalidOffset;
+}
+
+// ----------------------------------------------------------------------------
+// wxInputStream
+// ----------------------------------------------------------------------------
projects / wxWidgets.git / blobdiff