X-Git-Url: https://codewiz.org/gitweb?a=blobdiff_plain;f=mware%2Ffifobuf.h;h=e8eb6d942f26a61cc9d04c8578ffdc68182f0faa;hb=32841198fc4373115f71761a05088d10f0826223;hp=a643a7e6ed2e2fe9a0986fd9d3ad2f2e5596755a;hpb=d8c41d44af59c3b699736024da1ccc11efa52384;p=bertos.git

diff --git a/mware/fifobuf.h b/mware/fifobuf.h
index a643a7e6..e8eb6d94 100755
--- a/mware/fifobuf.h
+++ b/mware/fifobuf.h
@@ -41,38 +41,63 @@
  *		\code head == begin && tail == end \endcode
  */
 
-/*
- * $Log$
- * Revision 1.11  2004/07/30 14:15:53  rasky
- * Nuovo supporto unificato per detect della CPU
- *
- * Revision 1.10  2004/07/29 22:57:09  bernie
- * Doxygen fix.
- *
- * Revision 1.9  2004/07/20 23:54:27  bernie
- * fifo_flush_locked(): New function;
- * Revamp documentation.
- *
- * Revision 1.8  2004/07/20 23:47:39  bernie
- * Finally remove redundant protos.
- *
- * Revision 1.7  2004/07/20 23:46:29  bernie
- * Finally remove redundant protos.
- *
- * Revision 1.6  2004/06/06 17:18:04  bernie
- * Remove redundant declaration of fifo_isempty_locked().
- *
- * Revision 1.5  2004/06/06 16:50:35  bernie
- * Import fixes for race conditions from project_ks.
- *
- * Revision 1.4  2004/06/06 16:11:17  bernie
- * Protect MetroWerks specific pragmas with #ifdef's
- */
+/*#*
+ *#* $Log$
+ *#* Revision 1.19  2004/12/08 08:30:12  bernie
+ *#* Add missing header.
+ *#*
+ *#* Revision 1.18  2004/11/16 21:55:12  bernie
+ *#* Workaround for a known fifobuf bug.
+ *#*
+ *#* Revision 1.17  2004/09/14 20:57:00  bernie
+ *#* Use debug.h instead of kdebug.h.
+ *#*
+ *#* Revision 1.16  2004/09/06 21:39:08  bernie
+ *#* Simplify code using ATOMIC().
+ *#*
+ *#* Revision 1.15  2004/08/29 22:05:16  bernie
+ *#* Rename BITS_PER_PTR to CPU_BITS_PER_PTR.
+ *#*
+ *#* Revision 1.14  2004/08/25 14:12:09  rasky
+ *#* Aggiornato il comment block dei log RCS
+ *#*
+ *#* Revision 1.13  2004/08/24 13:16:11  bernie
+ *#* Add type-size definitions for preprocessor.
+ *#*
+ *#* Revision 1.12  2004/08/02 20:20:29  aleph
+ *#* Merge from project_ks
+ *#*
+ *#* Revision 1.11  2004/07/30 14:15:53  rasky
+ *#* Nuovo supporto unificato per detect della CPU
+ *#*
+ *#* Revision 1.10  2004/07/29 22:57:09  bernie
+ *#* Doxygen fix.
+ *#*
+ *#* Revision 1.9  2004/07/20 23:54:27  bernie
+ *#* fifo_flush_locked(): New function;
+ *#* Revamp documentation.
+ *#*
+ *#* Revision 1.8  2004/07/20 23:47:39  bernie
+ *#* Finally remove redundant protos.
+ *#*
+ *#* Revision 1.7  2004/07/20 23:46:29  bernie
+ *#* Finally remove redundant protos.
+ *#*
+ *#* Revision 1.6  2004/06/06 17:18:04  bernie
+ *#* Remove redundant declaration of fifo_isempty_locked().
+ *#*
+ *#* Revision 1.5  2004/06/06 16:50:35  bernie
+ *#* Import fixes for race conditions from project_ks.
+ *#*
+ *#* Revision 1.4  2004/06/06 16:11:17  bernie
+ *#* Protect MetroWerks specific pragmas with #ifdef's
+ *#*/
 
 #ifndef MWARE_FIFO_H
 #define MWARE_FIFO_H
 
-#include "cpu.h"
+#include <cpu.h>
+#include <debug.h>
 
 typedef struct FIFOBuffer
 {
@@ -83,6 +108,15 @@ typedef struct FIFOBuffer
 } FIFOBuffer;
 
 
+#define ASSERT_VALID_FIFO(fifo) \
+	ATOMIC( \
+		ASSERT((fifo)->head >= (fifo)->begin); \
+		ASSERT((fifo)->head <= (fifo)->end); \
+		ASSERT((fifo)->tail >= (fifo)->begin); \
+		ASSERT((fifo)->tail <= (fifo)->end); \
+	)
+
+
 /*!
  * Check whether the fifo is empty
  *
@@ -95,6 +129,7 @@ typedef struct FIFOBuffer
  */
 INLINE bool fifo_isempty(const FIFOBuffer *fb)
 {
+	//ASSERT_VALID_FIFO(fb);
 	return fb->head == fb->tail;
 }
 
@@ -114,6 +149,7 @@ INLINE bool fifo_isempty(const FIFOBuffer *fb)
  */
 INLINE bool fifo_isfull(const FIFOBuffer *fb)
 {
+	//ASSERT_VALID_FIFO(fb);
 	return
 		((fb->head == fb->begin) && (fb->tail == fb->end))
 		|| (fb->tail == fb->head - 1);
@@ -139,10 +175,12 @@ INLINE void fifo_push(FIFOBuffer *fb, unsigned char c)
 #ifdef __MWERKS__
 #pragma interrupt called
 #endif
+	//ASSERT_VALID_FIFO(fb);
+
 	/* Write at tail position */
 	*(fb->tail) = c;
 
-	if (fb->tail == fb->end)
+	if (UNLIKELY(fb->tail == fb->end))
 		/* wrap tail around */
 		fb->tail = fb->begin;
 	else
@@ -166,7 +204,9 @@ INLINE unsigned char fifo_pop(FIFOBuffer *fb)
 #ifdef __MWERKS__
 #pragma interrupt called
 #endif
-	if (fb->head == fb->end)
+	//ASSERT_VALID_FIFO(fb);
+
+	if (UNLIKELY(fb->head == fb->end))
 	{
 		/* wrap head around */
 		fb->head = fb->begin;
@@ -183,18 +223,23 @@ INLINE unsigned char fifo_pop(FIFOBuffer *fb)
  */
 INLINE void fifo_flush(FIFOBuffer *fb)
 {
+	//ASSERT_VALID_FIFO(fb);
 	fb->head = fb->tail;
 }
 
 
-#if !CPU_AVR
+#if CPU_REG_BITS >= CPU_BITS_PER_PTR
 
-	/* No tricks needed on 16/32bit CPUs */
-#	define fifo_isempty_locked(fb) fifo_isempty((fb))
-#	define fifo_push_locked(fb, c) fifo_push((fb), (c))
-#	define fifo_flush_locked(fb) fifo_flush((fb))
+	/*
+	 * 16/32bit CPUs that can update a pointer with a single write
+	 * operation, no need to disable interrupts.
+	 */
+	#define fifo_isempty_locked(fb) fifo_isempty((fb))
+	#define fifo_push_locked(fb, c) fifo_push((fb), (c))
+	#define fifo_pop_locked(fb)     fifo_pop((fb))
+	#define fifo_flush_locked(fb)   fifo_flush((fb))
 
-#else /* !CPU_AVR */
+#else /* CPU_REG_BITS < CPU_BITS_PER_PTR */
 
 	/*!
 	 * Similar to fifo_isempty(), but with stronger guarantees for
@@ -207,15 +252,11 @@ INLINE void fifo_flush(FIFOBuffer *fb)
 	INLINE bool fifo_isempty_locked(const FIFOBuffer *fb)
 	{
 		bool result;
-		cpuflags_t flags;
-
-		DISABLE_IRQSAVE(flags);
-		result = fifo_isempty(fb);
-		ENABLE_IRQRESTORE(flags);
-
+		ATOMIC(result = fifo_isempty(fb));
 		return result;
 	}
 
+
 	/*!
 	 * Similar to fifo_push(), but with stronger guarantees for
 	 * concurrent access between user and interrupt code.
@@ -226,10 +267,15 @@ INLINE void fifo_flush(FIFOBuffer *fb)
 	 */
 	INLINE void fifo_push_locked(FIFOBuffer *fb, unsigned char c)
 	{
-		cpuflags_t flags;
-		DISABLE_IRQSAVE(flags);
-		fifo_push(fb, c);
-		ENABLE_IRQRESTORE(flags);
+		ATOMIC(fifo_push(fb, c));
+	}
+
+	/* Probably not really needed, but hard to prove. */
+	INLINE unsigned char fifo_pop_locked(FIFOBuffer *fb)
+	{
+		unsigned char c;
+		ATOMIC(c = fifo_pop(fb));
+		return c;
 	}
 
 	/*!
@@ -242,13 +288,10 @@ INLINE void fifo_flush(FIFOBuffer *fb)
 	 */
 	INLINE void fifo_flush_locked(FIFOBuffer *fb)
 	{
-		cpuflags_t flags;
-		DISABLE_IRQSAVE(flags);
-		fifo_flush(fb);
-		ENABLE_IRQRESTORE(flags);
+		ATOMIC(fifo_flush(fb));
 	}
 
-#endif /* !__AVR__ */
+#endif /* CPU_REG_BITS < BITS_PER_PTR */
 
 
 /*!
@@ -256,14 +299,9 @@ INLINE void fifo_flush(FIFOBuffer *fb)
  */
 INLINE bool fifo_isfull_locked(const FIFOBuffer *_fb)
 {
-	bool _result;
-	cpuflags_t _flags;
-
-	DISABLE_IRQSAVE(_flags);
-	_result = fifo_isfull(_fb);
-	ENABLE_IRQRESTORE(_flags);
-
-	return _result;
+	bool result;
+	ATOMIC(result = fifo_isfull(_fb));
+	return result;
 }
 
 
@@ -272,6 +310,9 @@ INLINE bool fifo_isfull_locked(const FIFOBuffer *_fb)
  */
 INLINE void fifo_init(FIFOBuffer *fb, unsigned char *buf, size_t size)
 {
+	/* FIFO buffers have a known bug with 1-byte buffers. */
+	ASSERT(size > 1);
+
 	fb->head = fb->tail = fb->begin = buf;
 	fb->end = buf + size - 1;
 }