}
/* Set timeout. */
- port->timeouts.WriteTotalTimeoutConstant = timeout_ms;
- if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
- RETURN_FAIL("SetCommTimeouts() failed");
+ if (port->timeouts.WriteTotalTimeoutConstant != timeout_ms) {
+ port->timeouts.WriteTotalTimeoutConstant = timeout_ms;
+ if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
+ RETURN_FAIL("SetCommTimeouts() failed");
+ }
/* Start write. */
- if (WriteFile(port->hdl, buf, count, NULL, &port->write_ovl) == 0) {
- if (GetLastError() == ERROR_IO_PENDING) {
- DEBUG("Waiting for write to complete");
- GetOverlappedResult(port->hdl, &port->write_ovl, &bytes_written, TRUE);
- DEBUG_FMT("Write completed, %d/%d bytes written", bytes_written, count);
- RETURN_INT(bytes_written);
- } else {
- RETURN_FAIL("WriteFile() failed");
- }
- } else {
+ if (WriteFile(port->hdl, buf, count, NULL, &port->write_ovl)) {
DEBUG("Write completed immediately");
RETURN_INT(count);
+ } else if (GetLastError() == ERROR_IO_PENDING) {
+ DEBUG("Waiting for write to complete");
+ GetOverlappedResult(port->hdl, &port->write_ovl, &bytes_written, TRUE);
+ DEBUG_FMT("Write completed, %d/%d bytes written", bytes_written, count);
+ RETURN_INT(bytes_written);
+ } else {
+ RETURN_FAIL("WriteFile() failed");
}
#else
size_t bytes_written = 0;
}
/* Set timeout. */
- port->timeouts.WriteTotalTimeoutConstant = 0;
- if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
- RETURN_FAIL("SetCommTimeouts() failed");
+ if (port->timeouts.WriteTotalTimeoutConstant != 0) {
+ port->timeouts.WriteTotalTimeoutConstant = 0;
+ if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
+ RETURN_FAIL("SetCommTimeouts() failed");
+ }
/*
* Keep writing data until the OS has to actually start an async IO
#endif
}
+#ifdef _WIN32
+/* Restart wait operation if buffer was emptied. */
+static enum sp_return restart_wait_if_needed(struct sp_port *port, unsigned int bytes_read)
+{
+ DWORD errors;
+ COMSTAT comstat;
+
+ if (bytes_read == 0)
+ RETURN_OK();
+
+ if (ClearCommError(port->hdl, &errors, &comstat) == 0)
+ RETURN_FAIL("ClearCommError() failed");
+
+ if (comstat.cbInQue == 0)
+ TRY(restart_wait(port));
+
+ RETURN_OK();
+}
+#endif
+
SP_API enum sp_return sp_blocking_read(struct sp_port *port, void *buf,
size_t count, unsigned int timeout_ms)
{
#ifdef _WIN32
DWORD bytes_read = 0;
- DWORD bytes_remaining;
- int ret;
/* Set timeout. */
- port->timeouts.ReadIntervalTimeout = 0;
- port->timeouts.ReadTotalTimeoutConstant = timeout_ms;
- if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
- RETURN_FAIL("SetCommTimeouts() failed");
+ if (port->timeouts.ReadIntervalTimeout != 0 ||
+ port->timeouts.ReadTotalTimeoutConstant != timeout_ms) {
+ port->timeouts.ReadIntervalTimeout = 0;
+ port->timeouts.ReadTotalTimeoutConstant = timeout_ms;
+ if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
+ RETURN_FAIL("SetCommTimeouts() failed");
+ }
/* Start read. */
- if (ReadFile(port->hdl, buf, count, NULL, &port->read_ovl) == 0) {
- if (GetLastError() == ERROR_IO_PENDING) {
- DEBUG("Waiting for read to complete");
- GetOverlappedResult(port->hdl, &port->read_ovl, &bytes_read, TRUE);
- DEBUG_FMT("Read completed, %d/%d bytes read", bytes_read, count);
- } else {
- RETURN_FAIL("ReadFile() failed");
- }
- } else {
+ if (ReadFile(port->hdl, buf, count, NULL, &port->read_ovl)) {
DEBUG("Read completed immediately");
bytes_read = count;
+ } else if (GetLastError() == ERROR_IO_PENDING) {
+ DEBUG("Waiting for read to complete");
+ GetOverlappedResult(port->hdl, &port->read_ovl, &bytes_read, TRUE);
+ DEBUG_FMT("Read completed, %d/%d bytes read", bytes_read, count);
+ } else {
+ RETURN_FAIL("ReadFile() failed");
}
- ret = sp_input_waiting(port);
-
- if (ret < 0)
- RETURN_CODEVAL(ret);
-
- bytes_remaining = ret;
-
- /* Restart wait operation if buffer was emptied. */
- if (bytes_read > 0 && bytes_remaining == 0)
- TRY(restart_wait(port));
+ TRY(restart_wait_if_needed(port, bytes_read));
RETURN_INT(bytes_read);
#ifdef _WIN32
DWORD bytes_read;
- DWORD bytes_remaining;
- int ret;
/* Set timeout. */
- port->timeouts.ReadIntervalTimeout = MAXDWORD;
- port->timeouts.ReadTotalTimeoutConstant = 0;
- if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
- RETURN_FAIL("SetCommTimeouts() failed");
+ if (port->timeouts.ReadIntervalTimeout != MAXDWORD ||
+ port->timeouts.ReadTotalTimeoutConstant != 0) {
+ port->timeouts.ReadIntervalTimeout = MAXDWORD;
+ port->timeouts.ReadTotalTimeoutConstant = 0;
+ if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
+ RETURN_FAIL("SetCommTimeouts() failed");
+ }
/* Do read. */
if (ReadFile(port->hdl, buf, count, NULL, &port->read_ovl) == 0)
if (GetOverlappedResult(port->hdl, &port->read_ovl, &bytes_read, TRUE) == 0)
RETURN_FAIL("GetOverlappedResult() failed");
- ret = sp_input_waiting(port);
-
- if (ret < 0)
- RETURN_CODEVAL(ret);
-
- bytes_remaining = ret;
-
- /* Restart wait operation if buffer was emptied. */
- if (bytes_read > 0 && bytes_remaining == 0)
- TRY(restart_wait(port));
+ TRY(restart_wait_if_needed(port, bytes_read));
RETURN_INT(bytes_read);
#else