From da1b35c3274266e2328c952b78b969206f11d8ac Mon Sep 17 00:00:00 2001
From: richardbarry <richardbarry@1d2547de-c912-0410-9cb9-b8ca96c0e9e2>
Date: Wed, 26 Jun 2013 11:37:08 +0000
Subject: [PATCH] Add Newlib reent support.

git-svn-id: https://svn.code.sf.net/p/freertos/code/trunk@1952 1d2547de-c912-0410-9cb9-b8ca96c0e9e2
---
 FreeRTOS/Source/include/FreeRTOS.h |  4 ++++
 FreeRTOS/Source/tasks.c            | 23 +++++++++++++++++++++++
 2 files changed, 27 insertions(+)

diff --git a/FreeRTOS/Source/include/FreeRTOS.h b/FreeRTOS/Source/include/FreeRTOS.h
index 852e24c79..060523fee 100644
--- a/FreeRTOS/Source/include/FreeRTOS.h
+++ b/FreeRTOS/Source/include/FreeRTOS.h
@@ -576,6 +576,10 @@ typedef portBASE_TYPE (*pdTASK_HOOK_CODE)( void * );
 	#define configINCLUDE_APPLICATION_DEFINED_PRIVILEGED_FUNCTIONS 0
 #endif
 
+#ifndef configUSE_NEWLIB_REENTRANT
+	#define configUSE_NEWLIB_REENTRANT 0
+#endif
+
 /* For backward compatability. */
 #define eTaskStateGet eTaskGetState
 
diff --git a/FreeRTOS/Source/tasks.c b/FreeRTOS/Source/tasks.c
index e4e42c5a3..b8dd771ca 100644
--- a/FreeRTOS/Source/tasks.c
+++ b/FreeRTOS/Source/tasks.c
@@ -146,6 +146,14 @@ typedef struct tskTaskControlBlock
 		unsigned long ulRunTimeCounter;			/*< Stores the amount of time the task has spent in the Running state. */
 	#endif
 
+	#if ( configUSE_NEWLIB_REENTRANT == 1 )
+		/* Allocate a Newlib reent structure that is specific to this task.
+		Note Newlib support has been included by popular demand, but is not
+		used by the FreeRTOS maintainers themselves, and therefore receives
+		less rigorous testing than the rest of the FreeRTOS code. */
+		struct _reent xNewLib_reent;
+	#endif
+
 } tskTCB;
 
 
@@ -1858,6 +1866,14 @@ void vTaskSwitchContext( void )
 		taskSELECT_HIGHEST_PRIORITY_TASK();
 
 		traceTASK_SWITCHED_IN();
+
+		#if ( configUSE_NEWLIB_REENTRANT == 1 )
+		{
+			/* Switch Newlib's _impure_ptr variable to point to the _reent
+			structure specific to this task. */
+			_impure_ptr = &( pxCurrentTCB->xNewLib_reent );
+		}
+		#endif /* configUSE_NEWLIB_REENTRANT */
 	}
 }
 /*-----------------------------------------------------------*/
@@ -2319,6 +2335,13 @@ portBASE_TYPE x;
 		( void ) usStackDepth;
 	}
 	#endif /* portUSING_MPU_WRAPPERS */
+
+	#if ( configUSE_NEWLIB_REENTRANT == 1 )
+	{
+		/* Initialise this task's Newlib reent structure. */
+		_REENT_INIT_PTR( ( &( pxTCB->xNewLib_reent ) ) );
+	}
+	#endif /* configUSE_NEWLIB_REENTRANT */
 }
 /*-----------------------------------------------------------*/
 
-- 
2.39.5