* src/pic16/device.c (Pics16[]): added devices 18F2550, 18F4331,

[fw/sdcc] / device / include / pic16 / malloc.h

diff --git a/device/include/pic16/malloc.h b/device/include/pic16/malloc.h
index 4f9d24e7a0199b5b2fb751b2e77cbda7f8313ee7..173a6974e6353fb7adefddd076e95ca8f35ff684 100644 (file)
--- a/device/include/pic16/malloc.h
+++ b/device/include/pic16/malloc.h
@@ -3,6 +3,25 @@
  *
  * written by Vangelis Rokas, 2004 (vrokas@otenet.gr)
  *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2, or (at your option) any
+ * later version.
+ *  
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * 
+ * In other words, you are welcome to use, share and improve this program.
+ * You are forbidden to forbid anyone else to use, share and improve
+ * what you give them.   Help stamp out software-hoarding!  
+ *
+ * $Id$
  */
 
 
@@ -17,43 +36,94 @@
 #ifndef __MALLOC_H__
 #define __MALLOC_H__
 
-#pragma library c
 
+/* set EMULATION to 1 to enable native Linux malloc emulation layer. This is
+ * for debugging purposes only */
+ 
+#ifndef EMULATION
 #define EMULATION      0
+#endif
 
 #if EMULATION
-#define malloc pic16_malloc
-#define free   pic16_free
-#define realloc        pic16_realloc
-#define calloc pic16_calloc
+//#define malloc       pic16_malloc
+//#define free pic16_free
+//#define realloc      pic16_realloc
+//#define calloc       pic16_calloc
+
+//#define lmalloc              pic16_lmalloc
+//#define lfree                pic16_lfree
+//#define lrealloc     pic16_lrealloc
+//#define lcalloc              pic16_lcalloc
 #define _MALLOC_SPEC
-#endif
+
+#else
+
+#pragma library c
 
 #define _MALLOC_SPEC   data
 
-#define MAX_BLOCK_SIZE 0x7f            /* 126 bytes */
+#endif
+
+/* when MALLOC_MAX_FIRST is 1, the memory allocator tries to find a block
+ * that fits the requested size without merging (initially), if this block
+ * is not found, then tries to merge adjacent blocks. If MALLOC_MAX_FIRST is
+ * set 0, then the allocator tries to merge adjacent blocks in the first
+ * place.  Both behaviours may give better results when used in certain
+ * circumstancs. I.e. if realloc is to be used, leaving some space after the
+ * block, will allow realloc to allocate it, otherwise it may result in much
+ * more memory fragmentation. An algorithm can be implemented to allow small
+ * fragments to be allocated but this is much too complicated for the PIC18F's
+ * architecture */
+#define MALLOC_MAX_FIRST       0
+
+#define MAX_BLOCK_SIZE 0x7f            /* 127 bytes */
 #define        MAX_HEAP_SIZE   0x200           /* 512 bytes */
 #define _MAX_HEAP_SIZE (MAX_HEAP_SIZE-1)
 
 #define ALLOC_FLAG             0x80
 #define HEADER_SIZE            1
 
-
+/* memory block header, max size 127 bytes, 126 usable */
 typedef union {
-       unsigned char datum;
-       struct {
-               unsigned count: 7;
-               unsigned alloc: 1;
-       } bits;
+  unsigned char datum;
+  struct {
+    unsigned count: 7;
+    unsigned alloc: 1;
+  } bits;
 } _malloc_rec;
 
 
-unsigned char _MALLOC_SPEC *malloc(unsigned char);
-void free(unsigned char _MALLOC_SPEC *);
-unsigned char _MALLOC_SPEC *calloc(unsigned char num);         //, unsigned char len);
+/* initialize heap, should be called before any call to malloc/realloc/calloc */
+void _initHeap(unsigned char _MALLOC_SPEC *dHeap, unsigned int heapsize);
+
+
+/* start searching for a block of size at least bSize, merge adjacent blocks
+ * if necessery */
+_malloc_rec _MALLOC_SPEC *_mergeHeapBlock(_malloc_rec _MALLOC_SPEC *sBlock, unsigned char bSize);
+
+
+/* allocate a memory block */
+unsigned char _MALLOC_SPEC *malloc(unsigned char len);
+
+
+/* same as malloc, but clear memory */
+unsigned char _MALLOC_SPEC *calloc(unsigned char len);
+
+
+/* expand or reduce a memory block, if mblock is NULL, then same as malloc */
 unsigned char _MALLOC_SPEC *realloc(unsigned char _MALLOC_SPEC *mblock, unsigned char len);
 
 
-#endif /* __MALLOC_H__ */
+/* free a memory block */
+void free(unsigned char _MALLOC_SPEC *);
+
+
+/* returns the size of all the unallocated memory */
+unsigned int memfree(void);
 
 
+/* return the size of the maximum unallocated memory block */
+unsigned int memfreemax(void);
+
+
+#endif /* __MALLOC_H__ */