export more symbols of PThread.

git-svn-id: https://rt-thread.googlecode.com/svn/trunk@2433 bbd45198-f89e-11dd-88c7-29a3b14d5316

components/drivers/include/drivers/spi.h

@@ -9,13 +9,19 @@
  *
  * Change Logs:
  * Date           Author       Notes
+ * 2012-11-23     Bernard      Add extern "C"
  */
 
 #ifndef __SPI_H__
 #define __SPI_H__
 
+#include <stdlib.h>
 #include <rtthread.h>
 
+#ifdef __cplusplus
+extern "C"{
+#endif
+
 #define RT_SPI_CPHA     (1<<0)                             /* bit[0]:CPHA, clock phase */
 #define RT_SPI_CPOL     (1<<1)                             /* bit[1]:CPOL, clock polarity */
 /**
@@ -247,4 +253,8 @@ rt_inline void rt_spi_message_append(struct rt_spi_message *list,
     message->next = RT_NULL;
 }
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif