wxUint32 wxSocketBase::DoRead(void* buffer_, wxUint32 nbytes)
{
+ wxCHECK_MSG( m_impl, 0, "socket must be valid" );
+
// We use pointer arithmetic here which doesn't work with void pointers.
char *buffer = static_cast<char *>(buffer_);
+ wxCHECK_MSG( buffer, 0, "NULL buffer" );
// Try the push back buffer first, even before checking whether the socket
// is valid to allow reading previously pushed back data from an already
nbytes -= total;
buffer += total;
- // If it's indeed closed or if read everything, there is nothing more to do.
- if ( !m_impl || !nbytes )
+ // we can't read anything [more] if we're not connected
+ if ( !m_connected )
return total;
- wxCHECK_MSG( buffer, 0, "NULL buffer" );
-
-
- // wxSOCKET_NOWAIT overrides all the other flags and means that we are
- // polling the socket and don't block at all.
- if ( m_flags & wxSOCKET_NOWAIT )
+ while ( nbytes )
{
- int ret = m_impl->Read(buffer, nbytes);
+ // our socket is non-blocking so Read() will return immediately if
+ // there is nothing to read yet and it's more efficient to try it first
+ // before entering WaitForRead() which is going to start dispatching
+ // GUI events and, even more importantly, we must do this under Windows
+ // where we're not going to get notifications about socket being ready
+ // for reading before we read all the existing data from it
+ const int ret = m_impl->Read(buffer, nbytes);
if ( ret == -1 )
{
- if ( m_impl->GetLastError() != wxSOCKET_WOULDBLOCK )
- SetError(wxSOCKET_IOERR);
- }
- else // not an error, even if we didn't read anything
- {
- total += ret;
- }
- }
- else // blocking socket
- {
- for ( ;; )
- {
- // Wait until socket becomes ready for reading
- if ( !WaitForRead() )
- break;
-
- // m_connected will be set to false if we lost connection while
- // waiting, there is no need to call Read() if this happened
- const int ret = m_connected ? m_impl->Read(buffer, nbytes) : -1;
- if ( ret == 0 )
+ if ( m_impl->GetLastError() == wxSOCKET_WOULDBLOCK )
{
- // for connection-oriented (e.g. TCP) sockets we can only read
- // 0 bytes if the other end has been closed, and for
- // connectionless ones (UDP) this flag doesn't make sense
- // anyhow so we can set it to true too without doing any harm
- m_closed = true;
- break;
- }
-
- if ( ret == -1 )
- break;
+ // if we don't want to wait, just return immediately
+ if ( m_flags & wxSOCKET_NOWAIT )
+ break;
- total += ret;
+ // otherwise wait until the socket becomes ready for reading
+ if ( !WaitForRead() )
+ {
+ // and exit if the timeout elapsed before it did
+ SetError(wxSOCKET_TIMEDOUT);
+ break;
+ }
- // If wxSOCKET_WAITALL is not set, we can leave now as we did read
- // something and we don't need to wait for all nbytes bytes to be
- // read.
- if ( !(m_flags & wxSOCKET_WAITALL) )
+ // retry reading
+ continue;
+ }
+ else // "real" error
+ {
+ SetError(wxSOCKET_IOERR);
break;
+ }
+ }
+ else if ( ret == 0 )
+ {
+ // for connection-oriented (e.g. TCP) sockets we can only read
+ // 0 bytes if the other end has been closed, and for connectionless
+ // ones (UDP) this flag doesn't make sense anyhow so we can set it
+ // to true too without doing any harm
+ m_closed = true;
+
+ // we're not going to read anything else and so if we haven't read
+ // anything (or not everything in wxSOCKET_WAITALL case) already,
+ // signal an error
+ if ( (m_flags & wxSOCKET_WAITALL) || !total )
+ SetError(wxSOCKET_IOERR);
+ break;
+ }
- // Otherwise continue reading until we do read everything.
- nbytes -= ret;
- if ( !nbytes )
- break;
+ total += ret;
- buffer += ret;
- }
+ // if we are happy to read something and not the entire nbytes bytes,
+ // then we're done
+ if ( !(m_flags & wxSOCKET_WAITALL) )
+ break;
- // it's an error to not read everything in wxSOCKET_WAITALL mode or to
- // not read anything otherwise
- if ( ((m_flags & wxSOCKET_WAITALL) && nbytes) || !total )
- SetError(wxSOCKET_IOERR);
+ nbytes -= ret;
+ buffer += ret;
}
return total;
}
// This function is a mirror image of DoRead() except that it doesn't use the
-// push back buffer, please see comments there
+// push back buffer and doesn't treat 0 return value specially (normally this
+// shouldn't happen at all here), so please see comments there for explanations
wxUint32 wxSocketBase::DoWrite(const void *buffer_, wxUint32 nbytes)
{
+ wxCHECK_MSG( m_impl, 0, "socket must be valid" );
+
const char *buffer = static_cast<const char *>(buffer_);
+ wxCHECK_MSG( buffer, 0, "NULL buffer" );
- // Return if there is nothing to read or the socket is (already?) closed.
- if ( !m_impl || !nbytes )
+ if ( !m_connected )
return 0;
- wxCHECK_MSG( buffer, 0, "NULL buffer" );
-
wxUint32 total = 0;
- if ( m_flags & wxSOCKET_NOWAIT )
+ while ( nbytes )
{
const int ret = m_impl->Write(buffer, nbytes);
if ( ret == -1 )
{
- if ( m_impl->GetLastError() != wxSOCKET_WOULDBLOCK )
- SetError(wxSOCKET_IOERR);
- }
- else
- {
- total += ret;
- }
- }
- else // blocking socket
- {
- for ( ;; )
- {
- if ( !WaitForWrite() )
- break;
-
- const int ret = m_connected ? m_impl->Write(buffer, nbytes) : -1;
- if ( ret == 0 )
+ if ( m_impl->GetLastError() == wxSOCKET_WOULDBLOCK )
{
- m_closed = true;
- break;
- }
+ if ( m_flags & wxSOCKET_NOWAIT )
+ break;
- if ( ret == -1 )
- break;
+ if ( !WaitForWrite() )
+ {
+ SetError(wxSOCKET_TIMEDOUT);
+ break;
+ }
- total += ret;
- if ( !(m_flags & wxSOCKET_WAITALL) )
+ continue;
+ }
+ else // "real" error
+ {
+ SetError(wxSOCKET_IOERR);
break;
+ }
+ }
- nbytes -= ret;
- if ( !nbytes )
- break;
+ total += ret;
- buffer += ret;
- }
+ if ( !(m_flags & wxSOCKET_WAITALL) )
+ break;
- if ( ((m_flags & wxSOCKET_WAITALL) && nbytes) || !total )
- SetError(wxSOCKET_IOERR);
+ nbytes -= ret;
+ buffer += ret;
}
return total;
timeLeft = 0;
}
- // This function is only called if wxSOCKET_BLOCK flag was not used and
- // so we should dispatch the events if there is an event loop capable
- // of doing it.
wxSocketEventFlags events;
if ( eventLoop )
{
projects / wxWidgets.git / commitdiff
