X-Git-Url: https://git.saurik.com/wxWidgets.git/blobdiff_plain/adc350786ef18378de54410646ef6c83ce985158..878711c01c1b9ad5b97d35f379a048b8ce1bfb49:/src/common/stream.cpp?ds=inline diff --git a/src/common/stream.cpp b/src/common/stream.cpp index 88a8ccc790..2770a5df20 100644 --- a/src/common/stream.cpp +++ b/src/common/stream.cpp @@ -7,7 +7,7 @@ // Created: 11/07/98 // RCS-ID: $Id$ // Copyright: (c) Guilhem Lavaux -// Licence: wxWindows license +// Licence: wxWindows licence ///////////////////////////////////////////////////////////////////////////// // ============================================================================ @@ -46,7 +46,7 @@ // ---------------------------------------------------------------------------- // the temporary buffer size used when copying from stream to stream -#define BUF_TEMP_SIZE 10000 +#define BUF_TEMP_SIZE 4096 // ============================================================================ // implementation @@ -58,7 +58,7 @@ void wxStreamBuffer::SetError(wxStreamError err) { - if ( m_stream->m_lasterror == wxStream_NOERROR ) + if ( m_stream && m_stream->m_lasterror == wxSTREAM_NO_ERROR ) m_stream->m_lasterror = err; } @@ -80,40 +80,31 @@ void wxStreamBuffer::Init() m_fixed = TRUE; } -wxStreamBuffer::wxStreamBuffer(wxStreamBase& stream, BufMode mode) +wxStreamBuffer::wxStreamBuffer(BufMode mode) { Init(); - m_stream = &stream; + m_stream = NULL; m_mode = mode; - m_flushable = TRUE; - m_destroystream = FALSE; + m_flushable = FALSE; } -wxStreamBuffer::wxStreamBuffer(BufMode mode) +wxStreamBuffer::wxStreamBuffer(wxStreamBase& stream, BufMode mode) { Init(); - wxASSERT_MSG(mode != read_write, wxT("you have to use the other ctor for read_write mode") ); - if ( mode == read ) - m_stream = new wxInputStream; - else if ( mode == write) - m_stream = new wxOutputStream; - else - m_stream = NULL; - + m_stream = &stream; m_mode = mode; - m_flushable = FALSE; - m_destroystream = TRUE; + m_flushable = TRUE; } wxStreamBuffer::wxStreamBuffer(const wxStreamBuffer& buffer) { - // doing this has big chances to lead to a crashwhen the source buffer is + // 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 && !buffer.m_destroystream, + wxASSERT_MSG( !buffer.m_destroybuf, _T("it's a bad idea to copy this buffer") ); m_buffer_start = buffer.m_buffer_start; @@ -125,7 +116,6 @@ wxStreamBuffer::wxStreamBuffer(const wxStreamBuffer& buffer) m_stream = buffer.m_stream; m_mode = buffer.m_mode; m_destroybuf = FALSE; - m_destroystream = FALSE; } void wxStreamBuffer::FreeBuffer() @@ -137,9 +127,6 @@ void wxStreamBuffer::FreeBuffer() wxStreamBuffer::~wxStreamBuffer() { FreeBuffer(); - - if ( m_destroystream ) - delete m_stream; } wxInputStream *wxStreamBuffer::GetInputStream() const @@ -195,14 +182,15 @@ void wxStreamBuffer::SetBufferIO(size_t bufsize) void wxStreamBuffer::ResetBuffer() { - wxCHECK_RET( m_stream, _T("should have a stream in wxStreamBuffer") ); + if ( m_stream ) + { + m_stream->Reset(); + m_stream->m_lastcount = 0; + } - m_stream->m_lasterror = wxStream_NOERROR; - m_stream->m_lastcount = 0; - if (m_mode == read && m_flushable) - m_buffer_pos = m_buffer_end; - else - m_buffer_pos = m_buffer_start; + 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) @@ -210,7 +198,9 @@ bool wxStreamBuffer::FillBuffer() { wxInputStream *inStream = GetInputStream(); - wxCHECK_MSG( inStream, FALSE, _T("should have a stream in wxStreamBuffer") ); + // 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 ) @@ -271,6 +261,7 @@ void wxStreamBuffer::GetFromBuffer(void *buffer, size_t size) void wxStreamBuffer::PutToBuffer(const void *buffer, size_t size) { size_t left = GetBytesLeft(); + if ( size > left ) { if ( m_fixed ) @@ -315,7 +306,7 @@ void wxStreamBuffer::PutChar(char c) // if we don't have buffer at all, just forward this call to the stream, if ( !HasBuffer() ) { - outStream->OnSysWrite(&c, 1); + outStream->OnSysWrite(&c, sizeof(c)); } else { @@ -323,11 +314,11 @@ void wxStreamBuffer::PutChar(char c) if ( !GetDataLeft() && !FlushBuffer() ) { // we don't - SetError(wxStream_WRITE_ERR); + SetError(wxSTREAM_WRITE_ERROR); } else { - PutToBuffer(&c, 1); + PutToBuffer(&c, sizeof(c)); m_stream->m_lastcount = 1; } } @@ -340,12 +331,12 @@ char wxStreamBuffer::Peek() if ( !GetDataLeft() ) { - SetError(wxStream_READ_ERR); + SetError(wxSTREAM_READ_ERROR); return 0; } char c; - GetFromBuffer(&c, 1); + GetFromBuffer(&c, sizeof(c)); m_buffer_pos--; return c; @@ -360,18 +351,18 @@ char wxStreamBuffer::GetChar() char c; if ( !HasBuffer() ) { - inStream->OnSysRead(&c, 1); + inStream->OnSysRead(&c, sizeof(c)); } else { if ( !GetDataLeft() ) { - SetError(wxStream_READ_ERR); + SetError(wxSTREAM_READ_ERROR); c = 0; } else { - GetFromBuffer(&c, 1); + GetFromBuffer(&c, sizeof(c)); m_stream->m_lastcount = 1; } } @@ -381,16 +372,18 @@ char wxStreamBuffer::GetChar() size_t wxStreamBuffer::Read(void *buffer, size_t size) { - wxInputStream *inStream = GetInputStream(); - - wxCHECK_MSG( inStream, 0, _T("should have a stream in wxStreamBuffer") ); - // lasterror is reset before all new IO calls - m_stream->m_lasterror = wxStream_NOERROR; + if ( m_stream ) + m_stream->Reset(); + size_t read; if ( !HasBuffer() ) { - m_stream->m_lastcount = inStream->OnSysRead(buffer, size); + wxInputStream *inStream = GetInputStream(); + + wxCHECK_MSG( inStream, 0, _T("should have a stream in wxStreamBuffer") ); + + read = inStream->OnSysRead(buffer, size); } else // we have a buffer, use it { @@ -410,7 +403,7 @@ size_t wxStreamBuffer::Read(void *buffer, size_t size) if ( !FillBuffer() ) { - SetError(wxStream_EOF); + SetError(wxSTREAM_EOF); break; } } @@ -421,10 +414,13 @@ size_t wxStreamBuffer::Read(void *buffer, size_t size) } } - m_stream->m_lastcount = orig_size - size; + read = orig_size - size; } - return m_stream->m_lastcount; + if ( m_stream ) + m_stream->m_lastcount = read; + + return read; } // this should really be called "Copy()" @@ -452,17 +448,22 @@ size_t wxStreamBuffer::Read(wxStreamBuffer *dbuf) size_t wxStreamBuffer::Write(const void *buffer, size_t size) { - wxOutputStream *outStream = GetOutputStream(); + if (m_stream) + { + // lasterror is reset before all new IO calls + m_stream->Reset(); + } - wxCHECK_MSG( outStream, 0, _T("should have a stream in wxStreamBuffer") ); - - // lasterror is reset before all new IO calls - m_stream->m_lasterror = wxStream_NOERROR; + size_t ret = 0; 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 - m_stream->m_lastcount = outStream->OnSysWrite(buffer, size); + ret = outStream->OnSysWrite(buffer, size); } else // we [may] have a buffer, use it { @@ -480,6 +481,7 @@ size_t wxStreamBuffer::Write(const void *buffer, size_t size) // // 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); @@ -488,7 +490,7 @@ size_t wxStreamBuffer::Write(const void *buffer, size_t size) if ( !FlushBuffer() ) { - SetError(wxStream_WRITE_ERR); + SetError(wxSTREAM_WRITE_ERROR); break; } @@ -502,10 +504,16 @@ size_t wxStreamBuffer::Write(const void *buffer, size_t size) } } - m_stream->m_lastcount = orig_size - size; + ret = orig_size - size; + } + + if (m_stream) + { + // i am not entirely sure what we do this for + m_stream->m_lastcount = ret; } - return m_stream->m_lastcount; + return ret; } size_t wxStreamBuffer::Write(wxStreamBuffer *sbuf) @@ -613,9 +621,19 @@ off_t wxStreamBuffer::Seek(off_t pos, wxSeekMode mode) off_t wxStreamBuffer::Tell() const { - off_t pos = m_stream->OnSysTell(); - if ( pos == wxInvalidOffset ) - return wxInvalidOffset; + off_t 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(); @@ -631,7 +649,7 @@ off_t wxStreamBuffer::Tell() const wxStreamBase::wxStreamBase() { - m_lasterror = wxStream_NOERROR; + m_lasterror = wxSTREAM_NO_ERROR; m_lastcount = 0; } @@ -665,31 +683,19 @@ wxInputStream::~wxInputStream() free(m_wback); } -size_t wxInputStream::OnSysRead(void * WXUNUSED(buffer), - size_t WXUNUSED(bufsize)) +bool wxInputStream::CanRead() const { - return 0; + // we don't know if there is anything to read or not and by default we + // prefer to be optimistic and try to read data unless we know for sure + // there is no more of it + return m_lasterror != wxSTREAM_EOF; } bool wxInputStream::Eof() const { - wxInputStream *self = wxConstCast(this, wxInputStream); - - char c; - self->Read(&c, 1); - - // some streams can know that they're at EOF before actually trying to - // read beyond the end of stream (e.g. files) while others have no way of - // knowing it, so to provide the same behaviour in all cases we only - // return TRUE from here if the character really couldn't be read - if ( !self->LastRead() && GetLastError() == wxSTREAM_EOF ) - { - return TRUE; - } - - self->Ungetch(c); - - return FALSE; + // the only way the base class can know we're at EOF is when we'd already + // tried to read beyond it in which case last error is set accordingly + return GetLastError() == wxSTREAM_EOF; } char *wxInputStream::AllocSpaceWBack(size_t needed_size) @@ -718,7 +724,7 @@ char *wxInputStream::AllocSpaceWBack(size_t needed_size) return m_wback; } -size_t wxInputStream::GetWBack(void *buf, size_t bsize) +size_t wxInputStream::GetWBack(void *buf, size_t size) { if (!m_wback) return 0; @@ -726,13 +732,13 @@ size_t wxInputStream::GetWBack(void *buf, size_t bsize) // how many bytes do we have in the buffer? size_t toget = m_wbacksize - m_wbackcur; - if ( bsize < toget ) + if ( size < toget ) { // we won't read everything - toget = bsize; + toget = size; } - // copy the data from the cache + // copy the data from the cache memcpy(buf, m_wback + m_wbackcur, toget); m_wbackcur += toget; @@ -751,52 +757,77 @@ size_t wxInputStream::GetWBack(void *buf, size_t bsize) size_t wxInputStream::Ungetch(const void *buf, size_t bufsize) { + if ( m_lasterror != wxSTREAM_NO_ERROR && m_lasterror != wxSTREAM_EOF ) + { + // can't operate on this stream until the error is cleared + return 0; + } + char *ptrback = AllocSpaceWBack(bufsize); if (!ptrback) return 0; + // Eof() shouldn't return TRUE any longer + if ( m_lasterror == wxSTREAM_EOF ) + m_lasterror = wxSTREAM_NO_ERROR; + memcpy(ptrback, buf, bufsize); return bufsize; } bool wxInputStream::Ungetch(char c) { - void *ptrback = AllocSpaceWBack(1); - if (!ptrback) - return FALSE; - - *(char *)ptrback = c; - return TRUE; + return Ungetch(&c, sizeof(c)) != 0; } char wxInputStream::GetC() { char c; - Read(&c, 1); + Read(&c, sizeof(c)); return c; } wxInputStream& wxInputStream::Read(void *buf, size_t size) { - size_t retsize = GetWBack(buf, size); - if (retsize == size) + char *p = (char *)buf; + m_lastcount = 0; + + size_t read = GetWBack(buf, size); + for ( ;; ) { - m_lastcount = size; - m_lasterror = wxStream_NOERROR; - return *this; + size -= read; + m_lastcount += read; + p += read; + + if ( !size ) + { + // we read the requested amount of data + break; + } + + if ( p != buf && !CanRead() ) + { + // we have already read something and we would block in OnSysRead() + // now: don't do it but return immediately + break; + } + + read = OnSysRead(p, size); + if ( !read ) + { + // no more data available + break; + } } - size -= retsize; - buf = (char *)buf + retsize; - m_lastcount = OnSysRead(buf, size) + retsize; return *this; } char wxInputStream::Peek() { char c; - Read(&c, 1); - if (m_lasterror == wxStream_NOERROR) + Read(&c, sizeof(c)); + if (m_lasterror == wxSTREAM_NO_ERROR) { Ungetch(c); return c; @@ -808,13 +839,17 @@ char wxInputStream::Peek() wxInputStream& wxInputStream::Read(wxOutputStream& stream_out) { char buf[BUF_TEMP_SIZE]; - size_t bytes_read = BUF_TEMP_SIZE; - while (bytes_read == BUF_TEMP_SIZE) + for ( ;; ) { - bytes_read = Read(buf, bytes_read).LastRead(); - bytes_read = stream_out.Write(buf, bytes_read).LastWrite(); + size_t bytes_read = Read(buf, WXSIZEOF(buf)).LastRead(); + if ( !bytes_read ) + break; + + if ( stream_out.Write(buf, bytes_read).LastWrite() != bytes_read ) + break; } + return *this; } @@ -827,7 +862,7 @@ off_t wxInputStream::SeekI(off_t pos, wxSeekMode mode) // I don't know whether it should be put as well in wxFileInputStream::OnSysSeek if (m_lasterror==wxSTREAM_EOF) - m_lasterror=wxSTREAM_NOERROR; + m_lasterror=wxSTREAM_NO_ERROR; /* RR: A call to SeekI() will automatically invalidate any previous call to Ungetch(), otherwise it would be possible to SeekI() to @@ -838,11 +873,11 @@ off_t wxInputStream::SeekI(off_t pos, wxSeekMode mode) buffer if possible, but is it really needed? It would only work when seeking in wxFromCurrent mode, else it would invalidate anyway... */ - + if (m_wback) { wxLogDebug( wxT("Seeking in stream which has data written back to it.") ); - + free(m_wback); m_wback = NULL; m_wbacksize = 0; @@ -883,7 +918,7 @@ size_t wxOutputStream::OnSysWrite(const void * WXUNUSED(buffer), void wxOutputStream::PutC(char c) { - Write(&c, 1); + Write(&c, sizeof(c)); } wxOutputStream& wxOutputStream::Write(const void *buffer, size_t size) @@ -1042,7 +1077,7 @@ char wxBufferedInputStream::Peek() wxInputStream& wxBufferedInputStream::Read(void *buf, size_t size) { // reset the error flag - m_lasterror = wxStream_NOERROR; + Reset(); // first read from the already cached data m_lastcount = GetWBack(buf, size); @@ -1070,18 +1105,18 @@ off_t wxBufferedInputStream::SeekI(off_t pos, wxSeekMode mode) // RR: Look at wxInputStream for comments. if (m_lasterror==wxSTREAM_EOF) - m_lasterror=wxSTREAM_NOERROR; + Reset(); if (m_wback) { wxLogDebug( wxT("Seeking in stream which has data written back to it.") ); - + free(m_wback); m_wback = NULL; m_wbacksize = 0; m_wbackcur = 0; } - + return m_i_streambuf->Seek(pos, mode); } @@ -1091,7 +1126,7 @@ off_t wxBufferedInputStream::TellI() const if (pos != wxInvalidOffset) pos -= (m_wbacksize - m_wbackcur); - + return pos; }