[Mesa-dev] [PATCH 3/5] mesa: add _mesa_bufferobj_range_mapped function

[Pi Tabred]

Add function to test if the buffer is already mapped and
if so, if the to be mapped range overlaps with the mapped range.
Modify the _mesa_InvalidateBufferSubData function to use
the new function.
---
 src/mesa/main/bufferobj.c | 52 +++++++++++++++++++++++++++++++++--------------
 1 file changed, 37 insertions(+), 15 deletions(-)

diff --git a/src/mesa/main/bufferobj.c b/src/mesa/main/bufferobj.c
index 8b5ebc4..bfeed83 100644
--- a/src/mesa/main/bufferobj.c
+++ b/src/mesa/main/bufferobj.c
@@ -241,6 +241,40 @@ buffer_object_subdata_range_good( struct gl_context * ctx, GLenum target,
 
 
 /**
+ * Tests if to be used range is already mapped.
+ * The regions do not overlap if and only if the end of the discard
+ * region is before the mapped region or the start of the discard region
+ * is after the mapped region.
+ *
+ * Note that 'end' and 'mappEnd' are the first byte *after* the discard
+ * region and the mapped region, repsectively.  It is okay for that byte
+ * to be mapped (for 'end') or discarded (for 'mapEnd').
+ *
+ * \param obj     Buffer object target on which to operate.
+ * \param offset  Offset of the first byte of the subdata range.
+ * \param size    Size, in bytes, of the subdata range.
+ * \return   true if ranges overlap, false otherwise
+ *
+ */
+static GLboolean
+_mesa_bufferobj_range_mapped( const struct gl_buffer_object *obj,
+                              GLintptr offset, GLsizeiptr size )
+{
+   if (_mesa_bufferobj_mapped(obj))
+   {
+      const GLintptr end = offset + size;
+      const GLintptr mapEnd = obj->Offset + obj->Length;
+
+      if (!(end <= obj->Offset || offset >= mapEnd))
+      {
+         return GL_TRUE;
+      }
+   }
+   return GL_FALSE;
+}
+
+
+/**
  * Allocate and initialize a new buffer object.
  * 
  * Default callback for the \c dd_function_table::NewBufferObject() hook.
@@ -2331,23 +2365,11 @@ _mesa_InvalidateBufferSubData(GLuint buffer, GLintptr offset,
     *     mapped by MapBuffer, or if the invalidate range intersects the range
     *     currently mapped by MapBufferRange."
     */
-   if (_mesa_bufferobj_mapped(bufObj)) {
-      const GLintptr mapEnd = bufObj->Offset + bufObj->Length;
-
-      /* The regions do not overlap if and only if the end of the discard
-       * region is before the mapped region or the start of the discard region
-       * is after the mapped region.
-       *
-       * Note that 'end' and 'mapEnd' are the first byte *after* the discard
-       * region and the mapped region, repsectively.  It is okay for that byte
-       * to be mapped (for 'end') or discarded (for 'mapEnd').
-       */
-      if (!(end <= bufObj->Offset || offset >= mapEnd)) {
-         _mesa_error(ctx, GL_INVALID_OPERATION,
+   if (_mesa_bufferobj_range_mapped(bufObj, offset, length)) {
+      _mesa_error(ctx, GL_INVALID_OPERATION,
                      "glInvalidateBufferSubData(intersection with mapped "
                      "range)");
-         return;
-      }
+      return;
    }
 
    /* We don't actually do anything for this yet.  Just return after
-- 
1.8.3.1