[Fix] (Texture): give glTexBuffer the sized-format check its TODO deferred and the target-taking forms their own INVALID_ENUM

MobileGL/MG_State/GLState/ProgramState/ShaderCompileTask.h

@@ -40,15 +40,21 @@ namespace MobileGL::MG_State::GLState {
         // binding array in the getter and its floor (the GL 4.5 core minimum of 84) is that same
         // array's width, so the backend's own number never moves it.
         limits.MaxUniformBufferBindings = bindingPoints;
+        // The storage-buffer ceiling has the same shape as GetIndexedBufferQueryPointCount's: the
+        // backend's count capped by the array, and the array alone when there is no backend. That
+        // "no backend" arm is not a detail - it is what the GPU-free test binary runs under, and
+        // it has to keep matching what glGetIntegerv answers there.
+        limits.MaxShaderStorageBufferBindings =
+            env.HasBackend()
+                ? std::min<Int>(bindingPoints, std::max<Int>(env.params.MaxShaderStorageBufferBindings, 0))
+                : bindingPoints;
         if (!env.HasBackend()) {
-            // No backend: the two backend-derived ceilings have nothing to be measured against,
+            // The two genuinely per-DEVICE ceilings have nothing to be measured against here, and
-            // and zero means "do not enforce this kind" rather than "reject everything".
+            // zero means "do not enforce this kind" rather than "reject everything".
             return limits;
         }
         limits.MaxSamplerBindings = std::max<Int>(env.params.MaxCombinedTextureImageUnits, 0);
         limits.MaxImageBindings = std::max<Int>(env.params.MaxImageUnits, 0);
-        limits.MaxShaderStorageBufferBindings =
-            std::min<Int>(bindingPoints, std::max<Int>(env.params.MaxShaderStorageBufferBindings, 0));
         return limits;
     }
 

MobileGL/MG_Test/Texture/TextureTest.cpp

@@ -5697,3 +5697,81 @@ TEST_F(TextureTest, CopyTexSubImage1DRejectsAnythingButTexture1D) {
 
     MG_Impl::GLImpl::BindTexture(GL_TEXTURE_2D, 0);
 }
+
+// ---------------------------------------------------------------------------------------------
+// The buffer-texture entry points' error taxonomy (GL 4.6 core 8.9 / GL_EXT_texture_buffer).
+// esextcTextureBufferErrors walks every OTHER texture target through glTexBuffer and
+// glTexBufferRange and reads the code back each time, then does the same for a format a buffer
+// texture cannot take. glTexBuffer carried `// TODO: make sure internalformat is in one of
+// supported format for TexBuffer` and never checked, and the wrong-target code came out of a
+// deeper "the bound object is not a buffer texture" arm whose code depends on which entry point
+// reached it - GL_INVALID_OPERATION, which belongs only to the name-taking DSA forms.
+// ---------------------------------------------------------------------------------------------
+
+TEST_F(TextureTest, TexBufferAndTexBufferRangeRejectANonBufferTargetWithInvalidEnum) {
+    GLuint buffer = 0;
+    MG_Impl::GLImpl::GenBuffers(1, &buffer);
+    MG_Impl::GLImpl::BindBuffer(GL_TEXTURE_BUFFER, buffer);
+    MG_Impl::GLImpl::BufferData(GL_TEXTURE_BUFFER, 64, nullptr, GL_STATIC_DRAW);
+    DrainPendingGlErrors();
+
+    static constexpr GLenum kWrongTargets[] = {
+        GL_TEXTURE_2D, GL_TEXTURE_2D_ARRAY, GL_TEXTURE_3D, GL_TEXTURE_CUBE_MAP, GL_TEXTURE_CUBE_MAP_ARRAY,
+    };
+    for (const GLenum target : kWrongTargets) {
+        MG_Impl::GLImpl::TexBuffer(target, GL_RGBA32I, buffer);
+        ExpectSingleGlError(GL_INVALID_ENUM);
+        MG_Impl::GLImpl::TexBufferRange(target, GL_RGBA32I, buffer, 0, 64);
+        ExpectSingleGlError(GL_INVALID_ENUM);
+    }
+
+    MG_Impl::GLImpl::BindBuffer(GL_TEXTURE_BUFFER, 0);
+    MG_Impl::GLImpl::DeleteBuffers(1, &buffer);
+    DrainPendingGlErrors();
+}
+
+TEST_F(TextureTest, TexBufferRejectsAnInternalFormatABufferTextureCannotTake) {
+    GLuint texture = 0;
+    MG_Impl::GLImpl::GenTextures(1, &texture);
+    MG_Impl::GLImpl::BindTexture(GL_TEXTURE_BUFFER, texture);
+    GLuint buffer = 0;
+    MG_Impl::GLImpl::GenBuffers(1, &buffer);
+    MG_Impl::GLImpl::BindBuffer(GL_TEXTURE_BUFFER, buffer);
+    MG_Impl::GLImpl::BufferData(GL_TEXTURE_BUFFER, 64, nullptr, GL_STATIC_DRAW);
+    DrainPendingGlErrors();
+
+    // GL_DEPTH_COMPONENT32F is the one the conformance suite passes: a sized format, just not one
+    // of the sized formats table 8.15 lists for a buffer texture.
+    MG_Impl::GLImpl::TexBuffer(GL_TEXTURE_BUFFER, GL_DEPTH_COMPONENT32F, buffer);
+    ExpectSingleGlError(GL_INVALID_ENUM);
+    MG_Impl::GLImpl::TexBufferRange(GL_TEXTURE_BUFFER, GL_DEPTH_COMPONENT32F, buffer, 0, 64);
+    ExpectSingleGlError(GL_INVALID_ENUM);
+
+    // A format the table DOES list still goes through.
+    MG_Impl::GLImpl::TexBuffer(GL_TEXTURE_BUFFER, GL_RGBA32I, buffer);
+    EXPECT_EQ(MG_Impl::GLImpl::GetError(), GL_NO_ERROR);
+
+    MG_Impl::GLImpl::BindTexture(GL_TEXTURE_BUFFER, 0);
+    MG_Impl::GLImpl::BindBuffer(GL_TEXTURE_BUFFER, 0);
+    MG_Impl::GLImpl::DeleteBuffers(1, &buffer);
+    DrainPendingGlErrors();
+}
+
+// The DSA form keeps its own, DIFFERENT code for the corresponding shape: a texture that is not a
+// buffer texture is a wrong OBJECT, not a wrong token. The two must not be unified.
+TEST_F(TextureTest, TextureBufferKeepsInvalidOperationForANonBufferTexture) {
+    GLuint texture = 0;
+    MG_Impl::GLImpl::CreateTextures(GL_TEXTURE_2D, 1, &texture);
+    GLuint buffer = 0;
+    MG_Impl::GLImpl::GenBuffers(1, &buffer);
+    MG_Impl::GLImpl::BindBuffer(GL_TEXTURE_BUFFER, buffer);
+    MG_Impl::GLImpl::BufferData(GL_TEXTURE_BUFFER, 64, nullptr, GL_STATIC_DRAW);
+    DrainPendingGlErrors();
+
+    MG_Impl::GLImpl::TextureBuffer(texture, GL_RGBA32I, buffer);
+    ExpectSingleGlError(GL_INVALID_OPERATION);
+
+    MG_Impl::GLImpl::BindBuffer(GL_TEXTURE_BUFFER, 0);
+    MG_Impl::GLImpl::DeleteBuffers(1, &buffer);
+    DrainPendingGlErrors();
+}