sdcc-3.9.0 fork implementing GNU assembler syntax

This fork aims to provide better support for stm8-binutils

1 files changed, 119 insertions, 0 deletions

diff --git a/device/lib/pic16/libc/stdlib/malloc.c b/device/lib/pic16/libc/stdlib/malloc.c
new file mode 100644
index 0000000..56d309d
--- /dev/null
+++ b/device/lib/pic16/libc/stdlib/malloc.c
@@ -0,0 +1,119 @@
+/*-------------------------------------------------------------------------
+   malloc.c - dynamic memory allocation
+
+   Copyright (C) 2004, Vangelis Rokas <vrokas at otenet.gr>
+
+   This library 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 library 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 library; see the file COPYING. If not, write to the
+   Free Software Foundation, 51 Franklin Street, Fifth Floor, Boston,
+   MA 02110-1301, USA.
+
+   As a special exception, if you link this library with other files,
+   some of which are compiled with SDCC, to produce an executable,
+   this library does not by itself cause the resulting executable to
+   be covered by the GNU General Public License. This exception does
+   not however invalidate any other reasons why the executable file
+   might be covered by the GNU General Public License.
+-------------------------------------------------------------------------*/
+
+#include <malloc.h>
+
+/* this is an external pointer to HEAP. It should be defined in
+ * the user's program, or it can be a symbol created by linker */
+extern unsigned char _MALLOC_SPEC *heap;
+
+unsigned char _MALLOC_SPEC *malloc(unsigned char len)
+{
+  _malloc_rec _MALLOC_SPEC *pHeap;			/* pointer to block header */
+  _malloc_rec _MALLOC_SPEC *temp;
+  unsigned char bLen, eLen;			/* size of block  */
+#if MALLOC_MAX_FIRST
+  unsigned char pass=1;
+#endif
+
+    if(len >= MAX_BLOCK_SIZE)
+      goto do_end;
+
+    pHeap = (_malloc_rec _MALLOC_SPEC *)&heap;
+
+    while(1) {
+      bLen = pHeap->bits.count;
+      
+      /* if datum is zero, then last block, return NULL */
+      if(pHeap->datum == 0) {
+#if !MALLOC_MAX_FIRST
+        goto do_end;
+#else
+        if(!pass)
+          goto do_end;
+        
+        /* in the first pass, we search for blocks that have
+         * the requested size, in the second pass, try to merge
+         * adjacent blocks to 'make' the requested block */
+        pHeap = (_malloc_rec _MALLOC_SPEC *)&heap;
+        pass--;
+        continue;
+#endif
+      }
+
+      /* if current block is allocated then proceed to next */
+      if(pHeap->bits.alloc)
+        goto do_continue;
+
+		
+      /* current block is not allocated, try to allocate */
+			
+      /* if current block is not enough for allocation, then proceed to next */
+      if(bLen <= len) {
+
+#if MALLOC_MAX_FIRST
+        /* if we are in the first pass, check next block */
+        if(pass)
+          goto do_continue;
+
+        /* otherwise try merge */
+#endif
+
+        temp = _mergeHeapBlock(pHeap, len);
+        
+        if(!temp)
+          /* otherwise proceed with next block */
+          goto do_continue;
+
+        //pHeap = temp; /* temp == pHeap */
+        bLen = pHeap->bits.count;
+      }
+
+      /* current block is enough to hold the new block */
+
+      /* allocate by filling the fields */
+      eLen = (len+1);
+      pHeap->datum = 0x80 | eLen;
+
+      if(bLen > eLen) {
+        /* if current block size is greater than the requested one,
+         * create a new empty block at the end of the newly allocated */
+        temp = (_malloc_rec _MALLOC_SPEC *)((unsigned int)pHeap + eLen);
+        temp->datum = (bLen - eLen);
+      }
+
+      return ((unsigned char _MALLOC_SPEC *)((unsigned int)pHeap + 1));
+
+do_continue:
+      pHeap = (_malloc_rec _MALLOC_SPEC *)((unsigned int)pHeap + bLen);
+    }
+
+do_end:
+  return ((unsigned char _MALLOC_SPEC *)0);
+
+}