+ if (bytes_read < count)
+ DEBUG("Read timed out");
+
+ RETURN_INT(bytes_read);
+#endif
+}
+
+SP_API enum sp_return sp_blocking_read_next(struct sp_port *port, void *buf,
+ size_t count, unsigned int timeout_ms)
+{
+ TRACE("%p, %p, %d, %d", port, buf, count, timeout_ms);
+
+ CHECK_OPEN_PORT();
+
+ if (!buf)
+ RETURN_ERROR(SP_ERR_ARG, "Null buffer");
+
+ if (count == 0)
+ RETURN_ERROR(SP_ERR_ARG, "Zero count");
+
+ if (timeout_ms)
+ DEBUG_FMT("Reading next max %d bytes from port %s, timeout %d ms",
+ count, port->name, timeout_ms);
+ else
+ DEBUG_FMT("Reading next max %d bytes from port %s, no timeout",
+ count, port->name);
+
+#ifdef _WIN32
+ DWORD bytes_read = 0;
+
+ /* If timeout_ms == 0, set maximum timeout. */
+ DWORD timeout_val = (timeout_ms == 0 ? MAXDWORD - 1 : timeout_ms);
+
+ /* Set timeout. */
+ if (port->timeouts.ReadIntervalTimeout != MAXDWORD ||
+ port->timeouts.ReadTotalTimeoutMultiplier != MAXDWORD ||
+ port->timeouts.ReadTotalTimeoutConstant != timeout_val) {
+ port->timeouts.ReadIntervalTimeout = MAXDWORD;
+ port->timeouts.ReadTotalTimeoutMultiplier = MAXDWORD;
+ port->timeouts.ReadTotalTimeoutConstant = timeout_val;
+ if (SetCommTimeouts(port->hdl, &port->timeouts) == 0)
+ RETURN_FAIL("SetCommTimeouts() failed");
+ }
+
+ /* Loop until we have at least one byte, or timeout is reached. */
+ while (bytes_read == 0) {
+ /* Start read. */
+ if (ReadFile(port->hdl, buf, (DWORD) count, &bytes_read, &port->read_ovl)) {
+ DEBUG("Read completed immediately");
+ } else if (GetLastError() == ERROR_IO_PENDING) {
+ DEBUG("Waiting for read to complete");
+ if (GetOverlappedResult(port->hdl, &port->read_ovl, &bytes_read, TRUE) == 0)
+ RETURN_FAIL("GetOverlappedResult() failed");
+ if (bytes_read > 0) {
+ DEBUG("Read completed");
+ } else if (timeout_ms > 0) {
+ DEBUG("Read timed out");
+ break;
+ } else {
+ DEBUG("Restarting read");
+ }
+ } else {
+ RETURN_FAIL("ReadFile() failed");
+ }
+ }
+
+ TRY(restart_wait_if_needed(port, bytes_read));
+
+ RETURN_INT(bytes_read);
+
+#else
+ size_t bytes_read = 0;
+ struct timeout timeout;
+ fd_set fds;
+ ssize_t result;
+
+ timeout_start(&timeout, timeout_ms);
+
+ FD_ZERO(&fds);
+ FD_SET(port->fd, &fds);
+
+ /* Loop until we have at least one byte, or timeout is reached. */
+ while (bytes_read == 0) {
+
+ if (timeout_check(&timeout))
+ /* Timeout has expired. */
+ break;
+
+ result = select(port->fd + 1, &fds, NULL, NULL, timeout_timeval(&timeout));
+
+ timeout_update(&timeout);
+
+ if (result < 0) {
+ if (errno == EINTR) {
+ DEBUG("select() call was interrupted, repeating");
+ continue;
+ } else {
+ RETURN_FAIL("select() failed");
+ }
+ } else if (result == 0) {
+ /* Timeout has expired. */
+ break;
+ }
+
+ /* Do read. */
+ result = read(port->fd, buf, count);
+
+ if (result < 0) {
+ if (errno == EAGAIN)
+ /* This shouldn't happen because we did a select() first, but handle anyway. */
+ continue;
+ else
+ /* This is an actual failure. */
+ RETURN_FAIL("read() failed");
+ }
+
+ bytes_read = result;
+ }
+
+ if (bytes_read == 0)
+ DEBUG("Read timed out");
+