3 #include <msp/core/systemerror.h>
4 #include "eventreader.h"
5 #include "handle_private.h"
12 struct EventReader::Private
14 OVERLAPPED overlapped;
24 EventReader::EventReader(Handle &h, unsigned size):
28 memset(&priv->overlapped, 0, sizeof(OVERLAPPED));
29 *priv->event = CreateEvent(0, true, false, 0);
30 priv->overlapped.hEvent = *priv->event;
31 priv->buf_size = size;
32 priv->buffer = new char[priv->buf_size];
34 priv->buf_next = priv->buffer;
35 priv->pending = false;
38 EventReader::~EventReader()
40 CloseHandle(*priv->event);
41 delete[] priv->buffer;
45 const Handle &EventReader::get_event()
51 void EventReader::start()
53 if(priv->buf_avail || priv->pending)
57 priv->buf_next = priv->buffer;
58 if(!ReadFile(*handle, priv->buffer, priv->buf_size, &ret, &priv->overlapped))
60 unsigned err = GetLastError();
61 if(err==ERROR_IO_PENDING)
64 throw system_error("ReadFile");
68 priv->buf_avail = ret;
69 SetEvent(*priv->event);
73 void EventReader::wait()
79 if(!GetOverlappedResult(*handle, &priv->overlapped, &ret, true))
80 throw system_error("GetOverlappedResult");
83 priv->buf_avail = ret;
84 priv->pending = false;
88 unsigned EventReader::read(char *buf, unsigned len)
92 // No data in buffer, try to get some
97 len = min(len, priv->buf_avail);
98 memcpy(buf, priv->buf_next, len);
99 priv->buf_next += len;
100 priv->buf_avail -= len;
104 ResetEvent(*priv->event);