[Mesa-dev] [PATCH] mesa: remove usage of alloca in externalobjects.c v2

[Andres Rodriguez]

Don't want an overly large numBufferBarriers/numTextureBarriers to blow
up the stack.

v2: handle malloc errors

Suggested-by: Emil Velikov <emil.velikov at collabora.com>
Signed-off-by: Andres Rodriguez <andresx7 at gmail.com>
---
 src/mesa/main/externalobjects.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/src/mesa/main/externalobjects.c b/src/mesa/main/externalobjects.c
index 463debd268..6a248f35a6 100644
--- a/src/mesa/main/externalobjects.c
+++ b/src/mesa/main/externalobjects.c
@@ -727,34 +727,37 @@ _mesa_WaitSemaphoreEXT(GLuint semaphore,
 
    ASSERT_OUTSIDE_BEGIN_END(ctx);
 
    semObj = _mesa_lookup_semaphore_object(ctx, semaphore);
    if (!semObj)
       return;
 
    FLUSH_VERTICES(ctx, 0);
    FLUSH_CURRENT(ctx, 0);
 
-   bufObjs = alloca(sizeof(struct gl_buffer_object **) * numBufferBarriers);
+   bufObjs = malloc(sizeof(struct gl_buffer_object **) * numBufferBarriers);
    for (unsigned i = 0; i < numBufferBarriers; i++) {
       bufObjs[i] = _mesa_lookup_bufferobj(ctx, buffers[i]);
    }
 
-   texObjs = alloca(sizeof(struct gl_texture_object **) * numTextureBarriers);
+   texObjs = malloc(sizeof(struct gl_texture_object **) * numTextureBarriers);
    for (unsigned i = 0; i < numTextureBarriers; i++) {
       texObjs[i] = _mesa_lookup_texture(ctx, textures[i]);
    }
 
    ctx->Driver.ServerWaitSemaphoreObject(ctx, semObj,
                                          numBufferBarriers, bufObjs,
                                          numTextureBarriers, texObjs,
                                          srcLayouts);
+
+   free(bufObjs);
+   free(texObjs);
 }
 
 void GLAPIENTRY
 _mesa_SignalSemaphoreEXT(GLuint semaphore,
                          GLuint numBufferBarriers,
                          const GLuint *buffers,
                          GLuint numTextureBarriers,
                          const GLuint *textures,
                          const GLenum *dstLayouts)
 {
@@ -770,34 +773,37 @@ _mesa_SignalSemaphoreEXT(GLuint semaphore,
 
    ASSERT_OUTSIDE_BEGIN_END(ctx);
 
    semObj = _mesa_lookup_semaphore_object(ctx, semaphore);
    if (!semObj)
       return;
 
    FLUSH_VERTICES(ctx, 0);
    FLUSH_CURRENT(ctx, 0);
 
-   bufObjs = alloca(sizeof(struct gl_buffer_object **) * numBufferBarriers);
+   bufObjs = malloc(sizeof(struct gl_buffer_object **) * numBufferBarriers);
    for (unsigned i = 0; i < numBufferBarriers; i++) {
       bufObjs[i] = _mesa_lookup_bufferobj(ctx, buffers[i]);
    }
 
-   texObjs = alloca(sizeof(struct gl_texture_object **) * numTextureBarriers);
+   texObjs = malloc(sizeof(struct gl_texture_object **) * numTextureBarriers);
    for (unsigned i = 0; i < numTextureBarriers; i++) {
       texObjs[i] = _mesa_lookup_texture(ctx, textures[i]);
    }
 
    ctx->Driver.ServerSignalSemaphoreObject(ctx, semObj,
                                            numBufferBarriers, bufObjs,
                                            numTextureBarriers, texObjs,
                                            dstLayouts);
+
+   free(bufObjs);
+   free(texObjs);
 }
 
 void GLAPIENTRY
 _mesa_ImportMemoryFdEXT(GLuint memory,
                         GLuint64 size,
                         GLenum handleType,
                         GLint fd)
 {
    GET_CURRENT_CONTEXT(ctx);
 
-- 
2.14.1