From: Martin Ling <redacted>
Date: Wed, 20 Nov 2013 17:30:50 +0000 (+0000)
Subject: Add sp_drain() function.
X-Git-Tag: libserialport-0.1.0~84
X-Git-Url: https://sigrok.org/gitweb/?p=libserialport.git;a=commitdiff_plain;h=69a3739ca07a87d56e376a02f3bc1f0a0a9b64e7

Add sp_drain() function.
---

diff --git a/libserialport.h.in b/libserialport.h.in
index e866cab..79f315f 100644
--- a/libserialport.h.in
+++ b/libserialport.h.in
@@ -526,6 +526,14 @@ enum sp_return sp_write(struct sp_port *port, const void *buf, size_t count);
  */
 enum sp_return sp_flush(struct sp_port *port, enum sp_buffer buffers);
 
+/**
+ * Wait for buffered data to be transmitted.
+ *
+ * @return SP_OK on success, SP_ERR_FAIL on failure, or SP_ERR_ARG
+ *         if an invalid port is passed.
+ */
+enum sp_return sp_drain(struct sp_port *port);
+
 /**
  * @}
  * @defgroup Errors Obtaining error information
diff --git a/serialport.c b/serialport.c
index 92156b4..6104f24 100644
--- a/serialport.c
+++ b/serialport.c
@@ -535,6 +535,23 @@ enum sp_return sp_flush(struct sp_port *port, enum sp_buffer buffers)
 	return SP_OK;
 }
 
+enum sp_return sp_drain(struct sp_port *port)
+{
+	CHECK_PORT();
+
+#ifdef _WIN32
+	/* Returns non-zero upon success, 0 upon failure. */
+	if (FlushFileBuffers(port->hdl) == 0)
+		return SP_ERR_FAIL;
+#else
+	/* Returns 0 upon success, -1 upon failure. */
+	if (tcdrain(port->fd) < 0)
+		return SP_ERR_FAIL;
+#endif
+
+	return SP_OK;
+}
+
 enum sp_return sp_write(struct sp_port *port, const void *buf, size_t count)
 {
 	CHECK_PORT();