| 1 | ///////////////////////////////////////////////////////////////////////////// |
| 2 | // Name: src/common/mstream.cpp |
| 3 | // Purpose: "Memory stream" classes |
| 4 | // Author: Guilhem Lavaux |
| 5 | // Modified by: VZ (23.11.00): general code review |
| 6 | // Created: 04/01/98 |
| 7 | // RCS-ID: $Id$ |
| 8 | // Copyright: (c) Guilhem Lavaux |
| 9 | // Licence: wxWindows licence |
| 10 | ///////////////////////////////////////////////////////////////////////////// |
| 11 | |
| 12 | // ============================================================================ |
| 13 | // declarations |
| 14 | // ============================================================================ |
| 15 | |
| 16 | // ---------------------------------------------------------------------------- |
| 17 | // headers |
| 18 | // ---------------------------------------------------------------------------- |
| 19 | |
| 20 | // For compilers that support precompilation, includes "wx.h". |
| 21 | #include "wx/wxprec.h" |
| 22 | |
| 23 | #ifdef __BORLANDC__ |
| 24 | #pragma hdrstop |
| 25 | #endif |
| 26 | |
| 27 | #if wxUSE_STREAMS |
| 28 | |
| 29 | #include "wx/mstream.h" |
| 30 | |
| 31 | #ifndef WX_PRECOMP |
| 32 | #include "wx/stream.h" |
| 33 | #endif //WX_PRECOMP |
| 34 | |
| 35 | #include <stdlib.h> |
| 36 | |
| 37 | // ============================================================================ |
| 38 | // implementation |
| 39 | // ============================================================================ |
| 40 | |
| 41 | // ---------------------------------------------------------------------------- |
| 42 | // wxMemoryInputStream |
| 43 | // ---------------------------------------------------------------------------- |
| 44 | |
| 45 | IMPLEMENT_ABSTRACT_CLASS(wxMemoryInputStream, wxInputStream) |
| 46 | |
| 47 | wxMemoryInputStream::wxMemoryInputStream(const void *data, size_t len) |
| 48 | { |
| 49 | m_i_streambuf = new wxStreamBuffer(wxStreamBuffer::read); |
| 50 | m_i_streambuf->SetBufferIO((void *)data, len); // const_cast |
| 51 | m_i_streambuf->SetIntPosition(0); // seek to start pos |
| 52 | m_i_streambuf->Fixed(true); |
| 53 | |
| 54 | m_length = len; |
| 55 | } |
| 56 | |
| 57 | wxMemoryInputStream::wxMemoryInputStream(const wxMemoryOutputStream& stream) |
| 58 | { |
| 59 | const wxFileOffset lenFile = stream.GetLength(); |
| 60 | if ( lenFile == wxInvalidOffset ) |
| 61 | { |
| 62 | m_i_streambuf = NULL; |
| 63 | m_lasterror = wxSTREAM_EOF; |
| 64 | return; |
| 65 | } |
| 66 | |
| 67 | const size_t len = wx_truncate_cast(size_t, lenFile); |
| 68 | wxASSERT_MSG( len == lenFile + size_t(0), _T("huge files not supported") ); |
| 69 | |
| 70 | m_i_streambuf = new wxStreamBuffer(wxStreamBuffer::read); |
| 71 | m_i_streambuf->SetBufferIO(len); // create buffer |
| 72 | stream.CopyTo(m_i_streambuf->GetBufferStart(), len); |
| 73 | m_i_streambuf->SetIntPosition(0); // seek to start pos |
| 74 | m_i_streambuf->Fixed(true); |
| 75 | m_length = len; |
| 76 | } |
| 77 | |
| 78 | void |
| 79 | wxMemoryInputStream::InitFromStream(wxInputStream& stream, wxFileOffset lenFile) |
| 80 | { |
| 81 | if ( lenFile == wxInvalidOffset ) |
| 82 | lenFile = stream.GetLength(); |
| 83 | |
| 84 | if ( lenFile == wxInvalidOffset ) |
| 85 | { |
| 86 | m_i_streambuf = NULL; |
| 87 | m_lasterror = wxSTREAM_EOF; |
| 88 | return; |
| 89 | } |
| 90 | |
| 91 | const size_t len = wx_truncate_cast(size_t, lenFile); |
| 92 | wxASSERT_MSG( (wxFileOffset)len == lenFile, _T("huge files not supported") ); |
| 93 | |
| 94 | m_i_streambuf = new wxStreamBuffer(wxStreamBuffer::read); |
| 95 | m_i_streambuf->SetBufferIO(len); // create buffer |
| 96 | stream.Read(m_i_streambuf->GetBufferStart(), len); |
| 97 | m_i_streambuf->SetIntPosition(0); // seek to start pos |
| 98 | m_i_streambuf->Fixed(true); |
| 99 | m_length = stream.LastRead(); |
| 100 | } |
| 101 | |
| 102 | bool wxMemoryInputStream::CanRead() const |
| 103 | { |
| 104 | return m_i_streambuf->GetIntPosition() != m_length; |
| 105 | } |
| 106 | |
| 107 | wxMemoryInputStream::~wxMemoryInputStream() |
| 108 | { |
| 109 | delete m_i_streambuf; |
| 110 | } |
| 111 | |
| 112 | char wxMemoryInputStream::Peek() |
| 113 | { |
| 114 | char *buf = (char *)m_i_streambuf->GetBufferStart(); |
| 115 | size_t pos = m_i_streambuf->GetIntPosition(); |
| 116 | if ( pos == m_length ) |
| 117 | { |
| 118 | m_lasterror = wxSTREAM_READ_ERROR; |
| 119 | |
| 120 | return 0; |
| 121 | } |
| 122 | |
| 123 | return buf[pos]; |
| 124 | } |
| 125 | |
| 126 | size_t wxMemoryInputStream::OnSysRead(void *buffer, size_t nbytes) |
| 127 | { |
| 128 | size_t pos = m_i_streambuf->GetIntPosition(); |
| 129 | if ( pos == m_length ) |
| 130 | { |
| 131 | m_lasterror = wxSTREAM_EOF; |
| 132 | |
| 133 | return 0; |
| 134 | } |
| 135 | |
| 136 | m_i_streambuf->Read(buffer, nbytes); |
| 137 | m_lasterror = wxSTREAM_NO_ERROR; |
| 138 | |
| 139 | return m_i_streambuf->GetIntPosition() - pos; |
| 140 | } |
| 141 | |
| 142 | wxFileOffset wxMemoryInputStream::OnSysSeek(wxFileOffset pos, wxSeekMode mode) |
| 143 | { |
| 144 | return m_i_streambuf->Seek(pos, mode); |
| 145 | } |
| 146 | |
| 147 | wxFileOffset wxMemoryInputStream::OnSysTell() const |
| 148 | { |
| 149 | return m_i_streambuf->Tell(); |
| 150 | } |
| 151 | |
| 152 | // ---------------------------------------------------------------------------- |
| 153 | // wxMemoryOutputStream |
| 154 | // ---------------------------------------------------------------------------- |
| 155 | |
| 156 | IMPLEMENT_DYNAMIC_CLASS(wxMemoryOutputStream, wxOutputStream) |
| 157 | |
| 158 | wxMemoryOutputStream::wxMemoryOutputStream(void *data, size_t len) |
| 159 | { |
| 160 | m_o_streambuf = new wxStreamBuffer(wxStreamBuffer::write); |
| 161 | if ( data ) |
| 162 | m_o_streambuf->SetBufferIO(data, len); |
| 163 | m_o_streambuf->Fixed(false); |
| 164 | m_o_streambuf->Flushable(false); |
| 165 | } |
| 166 | |
| 167 | wxMemoryOutputStream::~wxMemoryOutputStream() |
| 168 | { |
| 169 | delete m_o_streambuf; |
| 170 | } |
| 171 | |
| 172 | size_t wxMemoryOutputStream::OnSysWrite(const void *buffer, size_t nbytes) |
| 173 | { |
| 174 | size_t oldpos = m_o_streambuf->GetIntPosition(); |
| 175 | m_o_streambuf->Write(buffer, nbytes); |
| 176 | size_t newpos = m_o_streambuf->GetIntPosition(); |
| 177 | |
| 178 | // FIXME can someone please explain what this does? (VZ) |
| 179 | if ( !newpos ) |
| 180 | newpos = m_o_streambuf->GetBufferSize(); |
| 181 | |
| 182 | return newpos - oldpos; |
| 183 | } |
| 184 | |
| 185 | wxFileOffset wxMemoryOutputStream::OnSysSeek(wxFileOffset pos, wxSeekMode mode) |
| 186 | { |
| 187 | return m_o_streambuf->Seek(pos, mode); |
| 188 | } |
| 189 | |
| 190 | wxFileOffset wxMemoryOutputStream::OnSysTell() const |
| 191 | { |
| 192 | return m_o_streambuf->Tell(); |
| 193 | } |
| 194 | |
| 195 | size_t wxMemoryOutputStream::CopyTo(void *buffer, size_t len) const |
| 196 | { |
| 197 | wxCHECK_MSG( buffer, 0, _T("must have buffer to CopyTo") ); |
| 198 | |
| 199 | if ( len > GetSize() ) |
| 200 | len = GetSize(); |
| 201 | |
| 202 | memcpy(buffer, m_o_streambuf->GetBufferStart(), len); |
| 203 | |
| 204 | return len; |
| 205 | } |
| 206 | |
| 207 | #endif // wxUSE_STREAMS |