mbed rtos - modified for the final project of the course "Advanced Operating Systems"

Dependents:   aos_mbed

Fork of mbed-rtos by mbed official

Revision:
6:350b53afb889
Child:
11:db1fc233faa9
diff -r 9654a71f5a90 -r 350b53afb889 rtx/rt_MemBox.c
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/rtx/rt_MemBox.c	Fri Nov 23 09:57:31 2012 +0000
@@ -0,0 +1,166 @@
+/*----------------------------------------------------------------------------
+ *      RL-ARM - RTX
+ *----------------------------------------------------------------------------
+ *      Name:    RT_MEMBOX.C
+ *      Purpose: Interface functions for fixed memory block management system
+ *      Rev.:    V4.60
+ *----------------------------------------------------------------------------
+ *
+ * Copyright (c) 1999-2009 KEIL, 2009-2012 ARM Germany GmbH
+ * All rights reserved.
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *  - Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  - Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *  - Neither the name of ARM  nor the names of its contributors may be used 
+ *    to endorse or promote products derived from this software without 
+ *    specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDERS AND CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *---------------------------------------------------------------------------*/
+
+#include "rt_TypeDef.h"
+#include "RTX_Config.h"
+#include "rt_System.h"
+#include "rt_MemBox.h"
+#include "rt_HAL_CM.h"
+
+/*----------------------------------------------------------------------------
+ *      Global Functions
+ *---------------------------------------------------------------------------*/
+
+
+/*--------------------------- _init_box -------------------------------------*/
+
+int _init_box  (void *box_mem, U32 box_size, U32 blk_size) {
+  /* Initialize memory block system, returns 0 if OK, 1 if fails. */
+  void *end;
+  void *blk;
+  void *next;
+  U32  sizeof_bm;
+
+  /* Create memory structure. */
+  if (blk_size & BOX_ALIGN_8) {
+    /* Memory blocks 8-byte aligned. */ 
+    blk_size = ((blk_size & ~BOX_ALIGN_8) + 7) & ~7;
+    sizeof_bm = (sizeof (struct OS_BM) + 7) & ~7;
+  }
+  else {
+    /* Memory blocks 4-byte aligned. */
+    blk_size = (blk_size + 3) & ~3;
+    sizeof_bm = sizeof (struct OS_BM);
+  }
+  if (blk_size == 0) {
+    return (1);
+  }
+  if ((blk_size + sizeof_bm) > box_size) {
+    return (1);
+  }
+  /* Create a Memory structure. */
+  blk = ((U8 *) box_mem) + sizeof_bm;
+  ((P_BM) box_mem)->free = blk;
+  end = ((U8 *) box_mem) + box_size;
+  ((P_BM) box_mem)->end      = end;
+  ((P_BM) box_mem)->blk_size = blk_size;
+
+  /* Link all free blocks using offsets. */
+  end = ((U8 *) end) - blk_size;
+  while (1)  {
+    next = ((U8 *) blk) + blk_size;
+    if (next > end)  break;
+    *((void **)blk) = next;
+    blk = next;
+  }
+  /* end marker */
+  *((void **)blk) = 0;
+  return (0);
+}
+
+/*--------------------------- rt_alloc_box ----------------------------------*/
+
+void *rt_alloc_box (void *box_mem) {
+  /* Allocate a memory block and return start address. */
+  void **free;
+#ifndef __USE_EXCLUSIVE_ACCESS
+  int  irq_dis;
+
+  irq_dis = __disable_irq ();
+  free = ((P_BM) box_mem)->free;
+  if (free) {
+    ((P_BM) box_mem)->free = *free;
+  }
+  if (!irq_dis) __enable_irq ();
+#else
+  do {
+    if ((free = (void **)__ldrex(&((P_BM) box_mem)->free)) == 0) {
+      __clrex();
+      break;
+    }
+  } while (__strex((U32)*free, &((P_BM) box_mem)->free));
+#endif
+  return (free);
+}
+
+
+/*--------------------------- _calloc_box -----------------------------------*/
+
+void *_calloc_box (void *box_mem)  {
+  /* Allocate a 0-initialized memory block and return start address. */
+  void *free;
+  U32 *p;
+  U32 i;
+
+  free = _alloc_box (box_mem);
+  if (free)  {
+    p = free;
+    for (i = ((P_BM) box_mem)->blk_size; i; i -= 4)  {
+      *p = 0;
+      p++;
+    }
+  }
+  return (free);
+}
+
+
+/*--------------------------- rt_free_box -----------------------------------*/
+
+int rt_free_box (void *box_mem, void *box) {
+  /* Free a memory block, returns 0 if OK, 1 if box does not belong to box_mem */
+#ifndef __USE_EXCLUSIVE_ACCESS
+  int irq_dis;
+#endif
+
+  if (box < box_mem || box >= ((P_BM) box_mem)->end) {
+    return (1);
+  }
+
+#ifndef __USE_EXCLUSIVE_ACCESS
+  irq_dis = __disable_irq ();
+  *((void **)box) = ((P_BM) box_mem)->free;
+  ((P_BM) box_mem)->free = box;
+  if (!irq_dis) __enable_irq ();
+#else
+  do {
+    *((void **)box) = (void *)__ldrex(&((P_BM) box_mem)->free);
+  } while (__strex ((U32)box, &((P_BM) box_mem)->free));
+#endif
+  return (0);
+}
+
+/*----------------------------------------------------------------------------
+ * end of file
+ *---------------------------------------------------------------------------*/
+