c0cb289d57
Summary: Specific changes: 1) Turn on -Werror so all warnings are errors 2) Fix some warnings the above now complains about 3) Add proper dependency support so changing a .h file forces a .c file to rebuild 4) Automatically use fbcode gcc on any internal machine rather than whatever system compiler is laying around 5) Fix jemalloc to once again be used in the builds (seemed like it wasn't being?) 6) Fix issue where 'git' would fail in build_detect_version because of LD_LIBRARY_PATH being set in the third-party build system Test Plan: make, make check, make clean, touch a header file, make sure rebuild is expected Reviewers: dhruba Reviewed By: dhruba Differential Revision: https://reviews.facebook.net/D7887
81 lines
2.1 KiB
C++
81 lines
2.1 KiB
C++
// Copyright (c) 2011 The LevelDB 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. See the AUTHORS file for names of contributors.
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#ifndef STORAGE_LEVELDB_DB_SNAPSHOT_H_
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#define STORAGE_LEVELDB_DB_SNAPSHOT_H_
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#include "leveldb/db.h"
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namespace leveldb {
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class SnapshotList;
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// Snapshots are kept in a doubly-linked list in the DB.
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// Each SnapshotImpl corresponds to a particular sequence number.
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class SnapshotImpl : public Snapshot {
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public:
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SequenceNumber number_; // const after creation
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private:
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friend class SnapshotList;
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// SnapshotImpl is kept in a doubly-linked circular list
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SnapshotImpl* prev_;
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SnapshotImpl* next_;
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SnapshotList* list_; // just for sanity checks
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};
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class SnapshotList {
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public:
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SnapshotList() {
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list_.prev_ = &list_;
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list_.next_ = &list_;
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list_.number_ = 0xFFFFFFFFL; // placeholder marker, for debugging
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}
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bool empty() const { return list_.next_ == &list_; }
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SnapshotImpl* oldest() const { assert(!empty()); return list_.next_; }
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SnapshotImpl* newest() const { assert(!empty()); return list_.prev_; }
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const SnapshotImpl* New(SequenceNumber seq) {
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SnapshotImpl* s = new SnapshotImpl;
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s->number_ = seq;
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s->list_ = this;
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s->next_ = &list_;
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s->prev_ = list_.prev_;
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s->prev_->next_ = s;
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s->next_->prev_ = s;
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return s;
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}
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void Delete(const SnapshotImpl* s) {
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assert(s->list_ == this);
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s->prev_->next_ = s->next_;
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s->next_->prev_ = s->prev_;
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delete s;
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}
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// retrieve all snapshot numbers. They are sorted in ascending order.
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void getAll(std::vector<SequenceNumber>& ret) {
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SnapshotImpl* s = &list_;
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if (empty()) return;
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SequenceNumber prev __attribute__((unused)) = 0;
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while (s->next_ != &list_) {
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assert(prev <= s->next_->number_);
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assert(prev = s->next_->number_); // assignment
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ret.push_back(s->next_->number_);
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s = s ->next_;
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}
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}
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private:
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// Dummy head of doubly-linked list of snapshots
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SnapshotImpl list_;
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};
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} // namespace leveldb
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#endif // STORAGE_LEVELDB_DB_SNAPSHOT_H_
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