Merge pull request #44 from mparisi20/decompOSAlloc

Decompile OSAlloc.o

1 files changed, 90 insertions, 0 deletions

diff --git a/src/SDK/OS/OSAlloc.c b/src/SDK/OS/OSAlloc.c
index 090233e..c553d8d 100644
--- a/src/SDK/OS/OSAlloc.c
+++ b/src/SDK/OS/OSAlloc.c
@@ -1,6 +1,30 @@
 #include "types.h"
+#include "consts.h"
 #include "OS/OSAlloc.h"
 
+inline Cell* DLAddFront(Cell* list, Cell* cell)
+{
+    cell->next = list;
+    cell->prev = NULL;
+
+    if (list != NULL)
+        list->prev = cell;
+    return cell;
+}
+
+inline Cell* DLExtract(Cell* list, Cell* cell)
+{
+    if (cell->next) {
+        cell->next->prev = cell->prev;
+    }
+    if (cell->prev == NULL) {
+        list = cell->next;
+    } else {
+        cell->prev->next = cell->next;
+    }
+    return list;
+}
+
 Cell *DLInsert(Cell *original, Cell *inserted)
 {
     Cell *prevCell = NULL;
@@ -47,3 +71,69 @@ Cell *DLInsert(Cell *original, Cell *inserted)
 
     return inserted;
 }
+
+extern HeapDesc *HeapArray; 
+
+#define HEADERSIZE OSi_ROUND(sizeof(Cell), 32)
+#define MINOBJSIZE (HEADERSIZE+32)
+
+void* OSAllocFromHeap(OSHeapHandle heap, u32 size) {
+    HeapDesc* hd;
+    Cell* cell;
+    Cell* newCell;
+    long leftoverSize;
+
+    hd = &HeapArray[heap];
+    
+    size += HEADERSIZE;
+    size = OSi_ROUND(size, 32);
+
+    for (cell = hd->free; cell != NULL; cell = cell->next) {
+        if ((long)size <= cell->size) {
+            break;
+        }
+    }
+
+    if (cell == NULL) {
+        return NULL;
+    }
+
+    leftoverSize = cell->size - (long)size;
+    if (leftoverSize < MINOBJSIZE) {
+        hd->free = DLExtract(hd->free, cell);
+    } else {
+        cell->size = (long)size;
+
+        newCell = (Cell *) ((char *)cell + size);
+        newCell->size = leftoverSize;
+
+        newCell->prev = cell->prev;
+        newCell->next = cell->next;
+
+        if (newCell->next != NULL) {
+            newCell->next->prev = newCell;
+        }
+
+        if (newCell->prev != NULL) {
+            newCell->prev->next = newCell;
+        } else {
+            hd->free = newCell;
+        }
+    }
+
+    hd->allocated = DLAddFront(hd->allocated, cell);
+
+    return (void *)((char *)cell + HEADERSIZE);
+}
+
+void OSFreeToHeap(OSHeapHandle heap, void* ptr) {
+    OSHeapInfo *heapInfo;
+    HeapDesc *hd;
+    Cell   *cell;
+
+    cell = (Cell *) ((char *)ptr - HEADERSIZE);
+    hd = &HeapArray[heap];
+    
+    hd->allocated = DLExtract(hd->allocated, cell);
+    hd->free = DLInsert(hd->free, cell);
+}