[Mesa-dev] [PATCH v3] glx: fix error code when there is no context bound

[Tapani Pälli]

From: Bernard Kilarski <bernard.r.kilarski at intel.com>

v2: change all related NULL checks to check against dummyContext
v3: really check for dummyContext *only* when ctx was from
    __glXGetCurrentContext

Signed-off-by: Bernard Kilarski <bernard.r.kilarski at intel.com>
Signed-off-by: Matt Roper <matthew.d.roper at intel.com>
Signed-off-by: Tapani Pälli <tapani.palli at intel.com>
Cc: "11.2" <mesa-stable at lists.freedesktop.org>
---
 src/glx/glx_pbuffer.c             |  2 +-
 src/glx/glxcmds.c                 | 12 ++++++------
 src/glx/query_renderer.c          |  4 ++--
 src/glx/tests/fake_glx_screen.cpp |  6 +++++-
 4 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/src/glx/glx_pbuffer.c b/src/glx/glx_pbuffer.c
index 231ab20..ab29899 100644
--- a/src/glx/glx_pbuffer.c
+++ b/src/glx/glx_pbuffer.c
@@ -328,7 +328,7 @@ GetDrawableAttribute(Display * dpy, GLXDrawable drawable,
        *   the calling thread's current context a GLXBadDrawable error is
        *   generated."
        */
-      if (pdraw == NULL || gc == NULL || gc->currentDpy != dpy ||
+      if (pdraw == NULL || gc == &dummyContext || gc->currentDpy != dpy ||
          (gc->currentDrawable != drawable &&
          gc->currentReadable != drawable)) {
          __glXSendError(dpy, GLXBadDrawable, drawable,
diff --git a/src/glx/glxcmds.c b/src/glx/glxcmds.c
index 589a87a..bff01d2 100644
--- a/src/glx/glxcmds.c
+++ b/src/glx/glxcmds.c
@@ -1728,7 +1728,7 @@ __glXSwapIntervalSGI(int interval)
    CARD32 *interval_ptr;
    CARD8 opcode;
 
-   if (gc == NULL) {
+   if (gc == &dummyContext) {
       return GLX_BAD_CONTEXT;
    }
 
@@ -1834,7 +1834,7 @@ __glXGetVideoSyncSGI(unsigned int *count)
    __GLXDRIdrawable *pdraw;
 #endif
 
-   if (!gc)
+   if (gc == &dummyContext)
       return GLX_BAD_CONTEXT;
 
 #ifdef GLX_DIRECT_RENDERING
@@ -1876,7 +1876,7 @@ __glXWaitVideoSyncSGI(int divisor, int remainder, unsigned int *count)
    if (divisor <= 0 || remainder < 0)
       return GLX_BAD_VALUE;
 
-   if (!gc)
+   if (gc == &dummyContext)
       return GLX_BAD_CONTEXT;
 
 #ifdef GLX_DIRECT_RENDERING
@@ -2189,7 +2189,7 @@ __glXSwapBuffersMscOML(Display * dpy, GLXDrawable drawable,
    struct glx_screen *psc = pdraw ? pdraw->psc : NULL;
 #endif
 
-   if (!gc) /* no GLX for this */
+   if (gc == &dummyContext) /* no GLX for this */
       return -1;
 
 #ifdef GLX_DIRECT_RENDERING
@@ -2408,7 +2408,7 @@ __glXBindTexImageEXT(Display * dpy,
 {
    struct glx_context *gc = __glXGetCurrentContext();
 
-   if (gc == NULL || gc->vtable->bind_tex_image == NULL)
+   if (gc == &dummyContext || gc->vtable->bind_tex_image == NULL)
       return;
 
    gc->vtable->bind_tex_image(dpy, drawable, buffer, attrib_list);
@@ -2419,7 +2419,7 @@ __glXReleaseTexImageEXT(Display * dpy, GLXDrawable drawable, int buffer)
 {
    struct glx_context *gc = __glXGetCurrentContext();
 
-   if (gc == NULL || gc->vtable->release_tex_image == NULL)
+   if (gc == &dummyContext || gc->vtable->release_tex_image == NULL)
       return;
 
    gc->vtable->release_tex_image(dpy, drawable, buffer);
diff --git a/src/glx/query_renderer.c b/src/glx/query_renderer.c
index 9108ec2..4debf06 100644
--- a/src/glx/query_renderer.c
+++ b/src/glx/query_renderer.c
@@ -106,7 +106,7 @@ glXQueryCurrentRendererIntegerMESA(int attribute, unsigned int *value)
 {
    struct glx_context *gc = __glXGetCurrentContext();
 
-   if (gc == NULL)
+   if (gc == &dummyContext)
       return False;
 
    return __glXQueryRendererInteger(gc->psc, attribute, value);
@@ -166,7 +166,7 @@ glXQueryCurrentRendererStringMESA(int attribute)
 {
    struct glx_context *gc = __glXGetCurrentContext();
 
-   if (gc == NULL)
+   if (gc == &dummyContext)
       return False;
 
    return __glXQueryRendererString(gc->psc, attribute);
diff --git a/src/glx/tests/fake_glx_screen.cpp b/src/glx/tests/fake_glx_screen.cpp
index db20749..c288aa6 100644
--- a/src/glx/tests/fake_glx_screen.cpp
+++ b/src/glx/tests/fake_glx_screen.cpp
@@ -75,7 +75,11 @@ indirect_create_context_attribs(struct glx_screen *base,
    return indirect_create_context(base, config_base, shareList, 0);
 }
 
-__thread void *__glX_tls_Context = NULL;
+/* This is necessary so that we don't have to link with glxcurrent.c
+ * which would require us to link with X libraries and what not.
+ */
+struct glx_context dummyContext;
+__thread void *__glX_tls_Context = &dummyContext;
 
 #if !defined(GLX_USE_TLS)
 extern "C" struct glx_context *
-- 
2.5.5