1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef CHROME_BROWSER_EXTENSIONS_REQUIREMENTS_CHECKER_H_ 6 #define CHROME_BROWSER_EXTENSIONS_REQUIREMENTS_CHECKER_H_ 7 8 #include <vector> 9 10 #include "base/callback.h" 11 #include "base/memory/ref_counted.h" 12 #include "base/memory/weak_ptr.h" 13 #include "chrome/browser/extensions/extension_service.h" 14 15 class GPUFeatureChecker; 16 17 namespace extensions { 18 class Extension; 19 20 // Validates the 'requirements' extension manifest field. This is an 21 // asynchronous process that involves several threads, but the public interface 22 // of this class (including constructor and destructor) must only be used on 23 // the UI thread. 24 class RequirementsChecker : public base::SupportsWeakPtr<RequirementsChecker> { 25 public: 26 RequirementsChecker(); 27 ~RequirementsChecker(); 28 29 // The vector passed to the callback are any localized errors describing 30 // requirement violations. If this vector is non-empty, requirements checking 31 // failed. This should only be called once. |callback| will always be invoked 32 // asynchronously on the UI thread. |callback| will only be called once, and 33 // will be reset after called. 34 void Check(scoped_refptr<const Extension> extension, 35 base::Callback<void(std::vector<std::string> requirement)> callback); 36 37 private: 38 // Callbacks for the GPUFeatureChecker. 39 void SetWebGLAvailability(bool available); 40 41 void MaybeRunCallback(); 42 43 std::vector<std::string> errors_; 44 45 // Every requirement that needs to be resolved asynchronously will add to 46 // this counter. When the counter is depleted, the callback will be run. 47 int pending_requirement_checks_; 48 49 scoped_refptr<GPUFeatureChecker> webgl_checker_; 50 51 base::Callback<void(std::vector<std::string> requirement_errorss)> callback_; 52 }; 53 54 } // namespace extensions 55 56 #endif // CHROME_BROWSER_EXTENSIONS_REQUIREMENTS_CHECKER_H_ 57