a5f4fe6b98
As the subject says, I don't think this can change any of the behavior, but the argument to Write() was ignored and merely confusing. BUG=chromium:339588 TEST=ran unit tests Change-Id: Ie6d59e6879a734523978c21d66170721e0f499c7 Reviewed-on: https://chromium-review.googlesource.com/194919 Tested-by: Luigi Semenzato <semenzato@chromium.org> Reviewed-by: Daniel Erat <derat@chromium.org> Reviewed-by: Luigi Semenzato <semenzato@chromium.org> Commit-Queue: Luigi Semenzato <semenzato@chromium.org>
66 lines
1.9 KiB
C++
66 lines
1.9 KiB
C++
// Copyright (c) 2014 The Chromium OS Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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#ifndef METRICS_PERSISTENT_INTEGER_H_
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#define METRICS_PERSISTENT_INTEGER_H_
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#include <base/basictypes.h>
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#include <string>
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namespace chromeos_metrics {
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// PersistentIntegers is a named 64-bit integer value backed by a file.
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// The in-memory value acts as a write-through cache of the file value.
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// If the backing file doesn't exist or has bad content, the value is 0.
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class PersistentInteger {
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public:
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PersistentInteger(const std::string& name);
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// Virtual only because of mock.
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virtual ~PersistentInteger();
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// Sets the value. This writes through to the backing file.
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void Set(int64 v);
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// Gets the value. May sync from backing file first.
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int64 Get();
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// Returns the name of the object.
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std::string Name() { return name_; }
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// Convenience function for Get() followed by Set(0).
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int64 GetAndClear();
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// Convenience function for v = Get, Set(v + x).
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// Virtual only because of mock.
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virtual void Add(int64 x);
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// After calling with |testing| = true, changes some behavior for the purpose
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// of testing. For instance: instances created while testing use the current
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// directory for the backing files.
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static void SetTestingMode(bool testing);
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private:
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static const int kVersion = 1001;
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// Writes |value_| to the backing file, creating it if necessary.
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void Write();
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// Reads the value from the backing file, stores it in |value_|, and returns
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// true if the backing file is valid. Returns false otherwise, and creates
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// a valid backing file as a side effect.
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bool Read();
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int64 value_;
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int32 version_;
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std::string name_;
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std::string backing_file_name_;
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bool synced_;
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static bool testing_;
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};
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}
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#endif // METRICS_PERSISTENT_INTEGER_H_
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