Mesa (master): mesa: create _mesa_attach_renderbuffer_without_ref() helper

[Timothy Arceri]

Module: Mesa
Branch: master
Commit: 074a485d35e75f514bf4d5c300442c2c4b4979ba
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=074a485d35e75f514bf4d5c300442c2c4b4979ba

Author: Timothy Arceri <tarceri at itsqueeze.com>
Date:   Sat Apr  8 10:03:20 2017 +1000

mesa: create _mesa_attach_renderbuffer_without_ref() helper

This will be used to take ownership of freashly created renderbuffers,
avoiding the need to call the reference function which requires
locking.

V2: dereference any existing fb attachments and actually attach the
    new rb.

v3: split out validation and attachment type/complete setting into
    a shared static function.

Reviewed-by: Emil Velikov <emil.velikov at collabora.com>
Tested-by: Bartosz Tomczyk <bartosz.tomczyk86 at gmail.com>

---

 src/mesa/main/renderbuffer.c | 43 +++++++++++++++++++++++++++++++++++--------
 src/mesa/main/renderbuffer.h |  5 +++++
 2 files changed, 40 insertions(+), 8 deletions(-)

diff --git a/src/mesa/main/renderbuffer.c b/src/mesa/main/renderbuffer.c
index 4375b5b882..627bdca66c 100644
--- a/src/mesa/main/renderbuffer.c
+++ b/src/mesa/main/renderbuffer.c
@@ -106,14 +106,10 @@ _mesa_delete_renderbuffer(struct gl_context *ctx, struct gl_renderbuffer *rb)
    free(rb);
 }
 
-
-/**
- * Attach a renderbuffer to a framebuffer.
- * \param bufferName  one of the BUFFER_x tokens
- */
-void
-_mesa_add_renderbuffer(struct gl_framebuffer *fb,
-                       gl_buffer_index bufferName, struct gl_renderbuffer *rb)
+static void
+validate_and_init_renderbuffer_attachment(struct gl_framebuffer *fb,
+                                          gl_buffer_index bufferName,
+                                          struct gl_renderbuffer *rb)
 {
    assert(fb);
    assert(rb);
@@ -137,6 +133,37 @@ _mesa_add_renderbuffer(struct gl_framebuffer *fb,
 
    fb->Attachment[bufferName].Type = GL_RENDERBUFFER_EXT;
    fb->Attachment[bufferName].Complete = GL_TRUE;
+}
+
+
+/**
+ * Attach a renderbuffer to a framebuffer.
+ * \param bufferName  one of the BUFFER_x tokens
+ *
+ * This function avoids adding a reference and is therefore intended to be
+ * used with a freashly created renderbuffer.
+ */
+void
+_mesa_add_renderbuffer_without_ref(struct gl_framebuffer *fb,
+                                   gl_buffer_index bufferName,
+                                   struct gl_renderbuffer *rb)
+{
+   validate_and_init_renderbuffer_attachment(fb, bufferName, rb);
+
+   _mesa_reference_renderbuffer(&fb->Attachment[bufferName].Renderbuffer,
+                                NULL);
+   fb->Attachment[bufferName].Renderbuffer = rb;
+}
+
+/**
+ * Attach a renderbuffer to a framebuffer.
+ * \param bufferName  one of the BUFFER_x tokens
+ */
+void
+_mesa_add_renderbuffer(struct gl_framebuffer *fb,
+                       gl_buffer_index bufferName, struct gl_renderbuffer *rb)
+{
+   validate_and_init_renderbuffer_attachment(fb, bufferName, rb);
    _mesa_reference_renderbuffer(&fb->Attachment[bufferName].Renderbuffer, rb);
 }
 
diff --git a/src/mesa/main/renderbuffer.h b/src/mesa/main/renderbuffer.h
index aa83120c1e..a6f1439498 100644
--- a/src/mesa/main/renderbuffer.h
+++ b/src/mesa/main/renderbuffer.h
@@ -47,6 +47,11 @@ extern void
 _mesa_delete_renderbuffer(struct gl_context *ctx, struct gl_renderbuffer *rb);
 
 extern void
+_mesa_add_renderbuffer_without_ref(struct gl_framebuffer *fb,
+                                   gl_buffer_index bufferName,
+                                   struct gl_renderbuffer *rb);
+
+extern void
 _mesa_add_renderbuffer(struct gl_framebuffer *fb,
                        gl_buffer_index bufferName, struct gl_renderbuffer *rb);