Make CreateAndConsumeTexture always associate client_id with a service_id

gpu/command_buffer/service/gles2_cmd_decoder.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "gpu/command_buffer/service/gles2_cmd_decoder.h"
 
 #include <stdio.h>
 
 #include <algorithm>
 #include <list>
@@ skipping 949 matching lines @@
       GLenum internal_format,
       GLsizei width,
       GLsizei height);
 
   void DoProduceTextureCHROMIUM(GLenum target, const GLbyte* key);
   void DoProduceTextureDirectCHROMIUM(GLuint texture, GLenum target,
       const GLbyte* key);
   void ProduceTextureRef(std::string func_name, TextureRef* texture_ref,
       GLenum target, const GLbyte* data);
 
+  void EnsureTextureForClientId(GLuint client_id);
   void DoConsumeTextureCHROMIUM(GLenum target, const GLbyte* key);
   void DoCreateAndConsumeTextureCHROMIUM(GLenum target, const GLbyte* key,
     GLuint client_id);
 
   bool DoIsValuebufferCHROMIUM(GLuint client_id);
   void DoBindValueBufferCHROMIUM(GLenum target, GLuint valuebuffer);
   void DoSubscribeValueCHROMIUM(GLenum target, GLenum subscription);
   void DoPopulateSubscribedValuesCHROMIUM(GLenum target);
   void DoUniformValueBufferCHROMIUM(GLint location,
                                     GLenum target,
@@ skipping 10692 matching lines @@
       break;
     case GL_TEXTURE_RECTANGLE_ARB:
       unit.bound_texture_rectangle_arb = texture_ref;
       break;
     default:
       NOTREACHED();  // Validation should prevent us getting here.
       break;
   }
 }
 
+void GLES2DecoderImpl::EnsureTextureForClientId(GLuint client_id) {
+  TextureRef* texture_ref = GetTexture(client_id);
+  if (!texture_ref) {
+    GLuint service_id;
+    glGenTextures(1, &service_id);
+    DCHECK_NE(0u, service_id);
+    CreateTexture(client_id, service_id);

[piman, 2015/04/03 18:17:14]

I think we also want to do the texture_manager()->SetTarget(texture_ref,
target); (that would be done in BindTexture), to make sure the texture would
have the right target.

Actually, I think we would also want to do the actual glBindTexture to create
the texture on the GL side, but then restore the currently bound texture
(because there shouldn't be the side effect on the context)

It matters in very subtle ways (e.g. if someone tries to bind the texture to a
framebuffer object).

+  }
+}
+
+// If CreateAndConsumeTexture fails we still need to ensure that the client_id
+// provided is associated with a service_id/TextureRef for consistency, even if
+// the resulting texture is incomplete.
 error::Error GLES2DecoderImpl::HandleCreateAndConsumeTextureCHROMIUMImmediate(
     uint32_t immediate_data_size,
     const void* cmd_data) {
   const gles2::cmds::CreateAndConsumeTextureCHROMIUMImmediate& c =
       *static_cast<
           const gles2::cmds::CreateAndConsumeTextureCHROMIUMImmediate*>(
           cmd_data);
   GLenum target = static_cast<GLenum>(c.target);
+  uint32_t client_id = c.client_id;
   uint32_t data_size;
   if (!ComputeDataSize(1, sizeof(GLbyte), 64, &data_size)) {
+    EnsureTextureForClientId(client_id);

[piman, 2015/04/03 18:17:14]

I think it's ok to skip here. We're losing the context anyway (this is what
would happen in the !immediate version).

     return error::kOutOfBounds;
   }
   if (data_size > immediate_data_size) {
+    EnsureTextureForClientId(client_id);

[piman, 2015/04/03 18:17:15]

Here too.

     return error::kOutOfBounds;
   }
   const GLbyte* mailbox =
       GetImmediateDataAs<const GLbyte*>(c, data_size, immediate_data_size);
   if (!validators_->texture_bind_target.IsValid(target)) {
+    EnsureTextureForClientId(client_id);

[piman, 2015/04/03 18:17:14]

Here too. Because we don't have a valid target, after the suggested change to
EnsureTextureForClientId, we wouldn't be able to SetTarget/glBindTexture anyway.

     LOCAL_SET_GL_ERROR_INVALID_ENUM(
         "glCreateAndConsumeTextureCHROMIUM", target, "target");
     return error::kNoError;
   }
   if (mailbox == NULL) {
+    EnsureTextureForClientId(client_id);

[piman, 2015/04/03 18:17:14]

Here too.

     return error::kOutOfBounds;
   }
-  uint32_t client_id = c.client_id;
   DoCreateAndConsumeTextureCHROMIUM(target, mailbox, client_id);
   return error::kNoError;
 }
 
 void GLES2DecoderImpl::DoCreateAndConsumeTextureCHROMIUM(GLenum target,
     const GLbyte* data, GLuint client_id) {
   TRACE_EVENT2("gpu", "GLES2DecoderImpl::DoCreateAndConsumeTextureCHROMIUM",
       "context", logger_.GetLogPrefix(),
       "mailbox[0]", static_cast<unsigned char>(data[0]));
   const Mailbox& mailbox = *reinterpret_cast<const Mailbox*>(data);
   DLOG_IF(ERROR, !mailbox.Verify()) << "CreateAndConsumeTextureCHROMIUM was "
                                        "passed a mailbox that was not "
                                        "generated by GenMailboxCHROMIUM.";
 
   TextureRef* texture_ref = GetTexture(client_id);
   if (texture_ref) {
+    // No need to call EnsureTextureForClientId here, the client_id already has
+    // an associated texture.
     LOCAL_SET_GL_ERROR(
         GL_INVALID_OPERATION,
         "glCreateAndConsumeTextureCHROMIUM", "client id already in use");
     return;
   }
   Texture* texture = group_->mailbox_manager()->ConsumeTexture(mailbox);
   if (!texture) {
+    EnsureTextureForClientId(client_id);
     LOCAL_SET_GL_ERROR(
         GL_INVALID_OPERATION,
         "glCreateAndConsumeTextureCHROMIUM", "invalid mailbox name");
     return;
   }
+
   if (texture->target() != target) {
+    EnsureTextureForClientId(client_id);
     LOCAL_SET_GL_ERROR(
         GL_INVALID_OPERATION,
         "glCreateAndConsumeTextureCHROMIUM", "invalid target");
     return;
   }
 
   texture_ref = texture_manager()->Consume(client_id, texture);
 }
 
 bool GLES2DecoderImpl::DoIsValuebufferCHROMIUM(GLuint client_id) {
@@ skipping 796 matching lines @@
   }
 }
 
 // Include the auto-generated part of this file. We split this because it means
 // we can easily edit the non-auto generated parts right here in this file
 // instead of having to edit some template or the code generator.
 #include "gpu/command_buffer/service/gles2_cmd_decoder_autogen.h"
 
 }  // namespace gles2
 }  // namespace gpu