Disable skipValidation when context is lost.

Lost no-error contexts should gracefully handle GetProgramiv, etc.

Includes test that a lost no-error context doesn't crash on getProgramiv.
Firefox bug: https://bugzilla.mozilla.org/show_bug.cgi?id=1601703

Bug: angleproject:4244
Change-Id: I8c37df37e83308ab85ad958df6dab46b0ab348e1
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2003239
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>

src/libANGLE/Context.cpp

@@ -2777,7 +2777,16 @@ void Context::markContextLost(GraphicsResetStatus status)
         mResetStatus       = status;
         mContextLostForced = true;
     }
+    setContextLost();
+}
+
+void Context::setContextLost()
+{
     mContextLost = true;
+
+    // Stop skipping validation, since many implementation entrypoint assume they can't
+    // be called when lost, or with null object arguments, etc.
+    mSkipValidation = false;
 }
 
 GLenum Context::getGraphicsResetStatus()
@@ -2786,9 +2795,9 @@ GLenum Context::getGraphicsResetStatus()
     // as it will allow us to skip all the calls.
     if (mResetStrategy == GL_NO_RESET_NOTIFICATION_EXT)
     {
-        if (!mContextLost && mImplementation->getResetStatus() != GraphicsResetStatus::NoError)
+        if (!isContextLost() && mImplementation->getResetStatus() != GraphicsResetStatus::NoError)
         {
-            mContextLost = true;
+            setContextLost();
         }
 
         // EXT_robustness, section 2.6: If the reset notification behavior is
@@ -2800,14 +2809,14 @@ GLenum Context::getGraphicsResetStatus()
     // The GL_EXT_robustness spec says that if a reset is encountered, a reset
     // status should be returned at least once, and GL_NO_ERROR should be returned
     // once the device has finished resetting.
-    if (!mContextLost)
+    if (!isContextLost())
     {
         ASSERT(mResetStatus == GraphicsResetStatus::NoError);
         mResetStatus = mImplementation->getResetStatus();
 
         if (mResetStatus != GraphicsResetStatus::NoError)
         {
-            mContextLost = true;
+            setContextLost();
         }
     }
     else if (!mContextLostForced && mResetStatus != GraphicsResetStatus::NoError)
@@ -5717,7 +5726,7 @@ void Context::framebufferTexture2DMultisample(GLenum target,
 void Context::getSynciv(GLsync sync, GLenum pname, GLsizei bufSize, GLsizei *length, GLint *values)
 {
     const Sync *syncObject = nullptr;
-    if (!mContextLost)
+    if (!isContextLost())
     {
         syncObject = getSync(sync);
     }
@@ -6430,7 +6439,7 @@ void Context::getIntegervRobust(GLenum pname, GLsizei bufSize, GLsizei *length,
 void Context::getProgramiv(ShaderProgramID program, GLenum pname, GLint *params)
 {
     Program *programObject = nullptr;
-    if (!mContextLost)
+    if (!isContextLost())
     {
         // Don't resolve link if checking the link completion status.
         programObject = (pname == GL_COMPLETION_STATUS_KHR ? getProgramNoResolveLink(program)
@@ -6485,7 +6494,7 @@ void Context::getProgramPipelineInfoLog(ProgramPipelineID pipeline,
 void Context::getShaderiv(ShaderProgramID shader, GLenum pname, GLint *params)
 {
     Shader *shaderObject = nullptr;
-    if (!mContextLost)
+    if (!isContextLost())
     {
         shaderObject = getShader(shader);
         ASSERT(shaderObject);

src/libANGLE/Context.h

@@ -453,6 +453,7 @@ class Context final : public egl::LabeledObject, angle::NonCopyable, public angl
     void markContextLost(GraphicsResetStatus status);
 
     bool isContextLost() const { return mContextLost; }
+    void setContextLost();
 
     GLenum getGraphicsResetStrategy() const { return mResetStrategy; }
     bool isResetNotificationEnabled();
@@ -512,9 +513,16 @@ class Context final : public egl::LabeledObject, angle::NonCopyable, public angl
     const TextureCapsMap &getTextureCaps() const { return mState.getTextureCaps(); }
     const Extensions &getExtensions() const { return mState.getExtensions(); }
     const Limitations &getLimitations() const { return mState.getLimitations(); }
-    bool skipValidation() const { return mSkipValidation; }
     bool isGLES1() const;
 
+    bool skipValidation() const
+    {
+        // Ensure we don't skip validation when context becomes lost, since implementations
+        // generally assume a non-lost context, non-null objects, etc.
+        ASSERT(!isContextLost() || !mSkipValidation);
+        return mSkipValidation;
+    }
+
     // Specific methods needed for validation.
     bool getQueryParameterInfo(GLenum pname, GLenum *type, unsigned int *numParams) const;
     bool getIndexedQueryParameterInfo(GLenum target, GLenum *type, unsigned int *numParams) const;
@@ -680,7 +688,7 @@ class Context final : public egl::LabeledObject, angle::NonCopyable, public angl
 
     // Current/lost context flags
     bool mHasBeenCurrent;
-    bool mContextLost;
+    bool mContextLost;  // Set with setContextLost so that we also set mSkipValidation=false.
     GraphicsResetStatus mResetStatus;
     bool mContextLostForced;
     GLenum mResetStrategy;

src/tests/gl_tests/ContextLostTest.cpp

@@ -103,6 +103,29 @@ TEST_P(ContextLostTest, ParallelCompileReadyQuery)
     EXPECT_GLENUM_EQ(linkStatus, 0xBADF00D);
 }
 
+class ContextLostSkipValidationTest : public ANGLETest
+{
+  protected:
+    ContextLostSkipValidationTest()
+    {
+        setContextResetStrategy(EGL_LOSE_CONTEXT_ON_RESET_EXT);
+        setNoErrorEnabled(true);
+    }
+};
+
+// Use GL_CHROMIUM_lose_context to lose a context and verify
+TEST_P(ContextLostSkipValidationTest, LostNoErrorGetProgram)
+{
+    ANGLE_SKIP_TEST_IF(!EnsureGLExtensionEnabled("GL_CHROMIUM_lose_context"));
+
+    GLuint program = glCreateProgram();
+
+    glLoseContextCHROMIUM(GL_GUILTY_CONTEXT_RESET, GL_INNOCENT_CONTEXT_RESET);
+
+    GLint val = 0;
+    glGetProgramiv(program, GL_INFO_LOG_LENGTH, &val);  // Should not crash.
+}
+
 // Use this to select which configurations (e.g. which renderer, which GLES major version) these
 // tests should be run against.
 ANGLE_INSTANTIATE_TEST(ContextLostTest,
@@ -113,4 +136,12 @@ ANGLE_INSTANTIATE_TEST(ContextLostTest,
                        ES2_VULKAN(),
                        ES3_VULKAN());
 
+ANGLE_INSTANTIATE_TEST(ContextLostSkipValidationTest,
+                       ES2_NULL(),
+                       ES2_D3D9(),
+                       ES2_D3D11(),
+                       ES3_D3D11(),
+                       ES2_VULKAN(),
+                       ES3_VULKAN());
+
 }  // namespace angle