1 files changed, 132 insertions, 0 deletions
diff --git a/src/offscreen_manager.c b/src/offscreen_manager.c
new file mode 100644
index 0000000..68c8632
--- /dev/null
+++ b/src/offscreen_manager.c
@@ -0,0 +1,132 @@
+/* **********************************************************
+ * Copyright (C) 1998-2002 VMware, Inc.
+ * All Rights Reserved
+ * **********************************************************/
+/* $XFree86: xc/programs/Xserver/hw/xfree86/drivers/vmware/offscreen_manager.c,v 1.2 2002/12/11 17:07:58 dawes Exp $ */
+
+#include "vmware.h"
+
+struct _Heap {
+    CARD8* ptr;
+    CARD32 size;
+    CARD32 maxSlots;
+    CARD32 startOffset;
+    SVGASurface* frontBuffer;
+    SVGASurface* slotsStart;
+    Bool clear;
+};
+
+static SVGASurface* FillInSurface(Heap* heap, SVGASurface* surface,
+                                  CARD32 width, CARD32 height,
+                                  CARD32 bpp, CARD32 pitch, CARD32 size,
+                                  CARD32 sizeUsed);
+
+Heap*
+vmwareHeap_Create(CARD8* ptr, CARD32 size, CARD32 maxSlots, CARD32 startOffset,
+            CARD32 sWidth, CARD32 sHeight, CARD32 sBPP, CARD32 sPitch,
+            CARD32 sFbOffset)
+{
+    Heap* newHeap = malloc(sizeof (Heap));
+
+    newHeap->ptr = ptr;
+    newHeap->size = size - sizeof(SVGASurface); /* leave room for frontbuffer */
+    newHeap->maxSlots = maxSlots;
+    newHeap->startOffset = startOffset;
+
+    newHeap->frontBuffer = FillInSurface(newHeap,
+                                         (SVGASurface*)(ptr + newHeap->size),
+                                         sWidth, sHeight, sBPP, sPitch,
+                                         sHeight * sPitch, 0);
+    newHeap->frontBuffer->dataOffset = sFbOffset;
+    newHeap->frontBuffer->numQueued = newHeap->frontBuffer->numDequeued = 0;
+
+    newHeap->slotsStart = (SVGASurface*)(newHeap->ptr + newHeap->size) - 
+                                          newHeap->maxSlots;
+    newHeap->clear = FALSE;
+    vmwareHeap_Clear(newHeap);
+
+    return newHeap;
+}
+
+void
+vmwareHeap_Destroy(Heap* heap)
+{
+    free(heap);
+}
+
+void
+vmwareHeap_Clear(Heap* heap)
+{
+    if (!heap->clear) {
+        memset(heap->slotsStart, 0, heap->maxSlots * sizeof (SVGASurface));
+        heap->clear = TRUE;
+    }
+}
+
+static SVGASurface*
+FillInSurface(Heap* heap, SVGASurface* surface, CARD32 width, CARD32 height,
+              CARD32 bpp, CARD32 pitch, CARD32 size, CARD32 offset)
+{
+    surface->size = sizeof (SVGASurface);
+    surface->version = SVGA_SURFACE_VERSION_1;
+    surface->bpp = bpp;
+    surface->width = width;
+    surface->height = height;
+    surface->pitch = pitch;
+    if (surface->userData == 0) {
+        /*
+         * We allocate exactly what we need the first time we use a slot, so
+         * all reuses of this slot will be equal or smaller.
+         */
+        surface->userData = size;
+    }
+    surface->dataOffset = offset + heap->startOffset;
+
+    return surface;
+}
+
+SVGASurface*
+vmwareHeap_GetFrontBuffer(Heap* heap)
+{
+   return heap->frontBuffer;
+}
+
+SVGASurface*
+vmwareHeap_AllocSurface(Heap* heap, CARD32 width, CARD32 height,
+                  CARD32 pitch, CARD32 bpp)
+{
+    CARD32 size = pitch * height;
+    CARD32 sizeUsed = 0;
+    SVGASurface* surface = heap->slotsStart;
+    int i;
+
+    /*
+     * NOTE: we use SVGASurface::userData to store the largest this slot's
+     * size has ever been, since we don't ever compact anything.
+     */
+
+    /* find a free slot that's big enough */
+    for (i = 0; i < heap->maxSlots; i++) {
+        if (surface[i].userData == 0) { /* this surface has never been used */
+            if ((CARD8*)heap->slotsStart - heap->ptr - sizeUsed < size) {
+                /* no room left for data*/
+                return NULL;
+            }
+
+            heap->clear = FALSE;
+            return FillInSurface(heap, surface + i, width, height, bpp,
+                                 pitch, size, sizeUsed);
+        }
+
+        if (surface[i].numQueued == surface[i].numDequeued &&
+            surface[i].userData >= size) { /* free and big enough, sweet! */
+            heap->clear = FALSE;
+            return FillInSurface(heap, surface + i, width, height, bpp,
+                                 pitch, size, sizeUsed);
+        }
+
+        sizeUsed += surface[i].userData;
+    }
+
+    return NULL;   
+}