Move _heap.h to the compiler include dir.

Create heap.inc and use that from the assembler code.
Rename heap related _h... variables to _heap...
Add _heapmaxavail and _heapmemavail functions.


git-svn-id: svn://svn.cc65.org/cc65/trunk@1912 b7a2c559-68d2-44c3-8de9-860c34a00d81

include/_heap.h

@@ -0,0 +1,43 @@
+/*
+ * _heap.h
+ *
+ * Ullrich von Bassewitz, 03.06.1998
+ *
+ */
+
+
+
+#ifndef __HEAP_H
+#define __HEAP_H
+
+
+
+/* Space needed for administering used blocks */
+#define HEAP_ADMIN_SPACE        sizeof (unsigned)
+
+/* The data type used to implement the free list.
+ * Beware: Field order is significant!
+ */
+struct freeblock {
+    unsigned 		size;
+    struct freeblock*  	next;
+    struct freeblock*  	prev;
+};
+
+
+
+/* Variables that describe the heap */
+extern unsigned*       	  _heaporg;     /* Bottom of heap */
+extern unsigned*  	  _heapptr;	/* Current top */
+extern unsigned*  	  _heapend;	/* Upper limit */
+extern struct freeblock*  _heapfirst;	/* First free block in list */
+extern struct freeblock*  _heaplast;	/* Last free block in list */
+
+
+
+/* End of _heap.h */
+
+#endif
+
+
+