From 74f032ff6f2465160366d865b1bb89a45dc2046b Mon Sep 17 00:00:00 2001 From: costan Date: Wed, 21 Mar 2018 00:47:18 -0700 Subject: [PATCH] leveldb: Require C++11. This CL switches the public headers to C++11 default and deleted constructors, and adds override to the relevant leveldb::EnvWrapper methods. This should be a good test for C++11 compiler support. Once this CL settles, the rest of the codebase can be safely modernized to C++11. ------------- Created by MOE: https://github.com/google/moe MOE_MIGRATED_REVID=189873212 --- CMakeLists.txt | 11 +++- include/leveldb/cache.h | 9 ++- include/leveldb/db.h | 11 ++-- include/leveldb/env.h | 121 +++++++++++++++++++++------------------- include/leveldb/filter_policy.h | 3 +- include/leveldb/iterator.h | 8 +-- include/leveldb/slice.h | 6 +- include/leveldb/table.h | 7 +-- include/leveldb/table_builder.h | 7 +-- include/leveldb/write_batch.h | 7 ++- 10 files changed, 101 insertions(+), 89 deletions(-) diff --git a/CMakeLists.txt b/CMakeLists.txt index 73b69a4..6f7c36a 100644 --- a/CMakeLists.txt +++ b/CMakeLists.txt @@ -3,11 +3,16 @@ # found in the LICENSE file. See the AUTHORS file for names of contributors. cmake_minimum_required(VERSION 3.9) -project(Leveldb VERSION 0.1.0 LANGUAGES C CXX) +project(Leveldb VERSION 1.21.0 LANGUAGES C CXX) -# This project can take advantage of C++11. +# This project can use C11, but will gracefully decay down to C89. +set(CMAKE_C_STANDARD 11) +set(CMAKE_C_STANDARD_REQUIRED OFF) +set(CMAKE_C_EXTENSIONS OFF) + +# This project requires C++11. set(CMAKE_CXX_STANDARD 11) -set(CMAKE_CXX_STANDARD_REQUIRED OFF) +set(CMAKE_CXX_STANDARD_REQUIRED ON) set(CMAKE_CXX_EXTENSIONS OFF) option(LEVELDB_BUILD_TESTS "Build LevelDB's unit tests" ON) diff --git a/include/leveldb/cache.h b/include/leveldb/cache.h index ed18baa..145ad69 100644 --- a/include/leveldb/cache.h +++ b/include/leveldb/cache.h @@ -32,7 +32,10 @@ LEVELDB_EXPORT Cache* NewLRUCache(size_t capacity); class LEVELDB_EXPORT Cache { public: - Cache() { } + Cache() = default; + + Cache(const Cache&) = delete; + Cache& operator=(const Cache&) = delete; // Destroys all existing entries by calling the "deleter" // function that was passed to the constructor. @@ -100,10 +103,6 @@ class LEVELDB_EXPORT Cache { struct Rep; Rep* rep_; - - // No copying allowed - Cache(const Cache&); - void operator=(const Cache&); }; } // namespace leveldb diff --git a/include/leveldb/db.h b/include/leveldb/db.h index e99f45c..092a154 100644 --- a/include/leveldb/db.h +++ b/include/leveldb/db.h @@ -53,7 +53,11 @@ class LEVELDB_EXPORT DB { const std::string& name, DB** dbptr); - DB() { } + DB() = default; + + DB(const DB&) = delete; + DB& operator=(const DB&) = delete; + virtual ~DB(); // Set the database entry for "key" to "value". Returns OK on success, @@ -142,11 +146,6 @@ class LEVELDB_EXPORT DB { // Therefore the following call will compact the entire database: // db->CompactRange(NULL, NULL); virtual void CompactRange(const Slice* begin, const Slice* end) = 0; - - private: - // No copying allowed - DB(const DB&); - void operator=(const DB&); }; // Destroy the contents of the specified database. diff --git a/include/leveldb/env.h b/include/leveldb/env.h index 9d8ebfe..54c9e3b 100644 --- a/include/leveldb/env.h +++ b/include/leveldb/env.h @@ -31,7 +31,11 @@ class WritableFile; class LEVELDB_EXPORT Env { public: - Env() { } + Env() = default; + + Env(const Env&) = delete; + Env& operator=(const Env&) = delete; + virtual ~Env(); // Return a default environment suitable for the current operating @@ -162,17 +166,16 @@ class LEVELDB_EXPORT Env { // Sleep/delay the thread for the prescribed number of micro-seconds. virtual void SleepForMicroseconds(int micros) = 0; - - private: - // No copying allowed - Env(const Env&); - void operator=(const Env&); }; // A file abstraction for reading sequentially through a file class LEVELDB_EXPORT SequentialFile { public: - SequentialFile() { } + SequentialFile() = default; + + SequentialFile(const SequentialFile&) = delete; + SequentialFile& operator=(const SequentialFile&) = delete; + virtual ~SequentialFile(); // Read up to "n" bytes from the file. "scratch[0..n-1]" may be @@ -193,17 +196,16 @@ class LEVELDB_EXPORT SequentialFile { // // REQUIRES: External synchronization virtual Status Skip(uint64_t n) = 0; - - private: - // No copying allowed - SequentialFile(const SequentialFile&); - void operator=(const SequentialFile&); }; // A file abstraction for randomly reading the contents of a file. class LEVELDB_EXPORT RandomAccessFile { public: - RandomAccessFile() { } + RandomAccessFile() = default; + + RandomAccessFile(const RandomAccessFile&) = delete; + RandomAccessFile& operator=(const RandomAccessFile&) = delete; + virtual ~RandomAccessFile(); // Read up to "n" bytes from the file starting at "offset". @@ -217,11 +219,6 @@ class LEVELDB_EXPORT RandomAccessFile { // Safe for concurrent use by multiple threads. virtual Status Read(uint64_t offset, size_t n, Slice* result, char* scratch) const = 0; - - private: - // No copying allowed - RandomAccessFile(const RandomAccessFile&); - void operator=(const RandomAccessFile&); }; // A file abstraction for sequential writing. The implementation @@ -229,45 +226,42 @@ class LEVELDB_EXPORT RandomAccessFile { // at a time to the file. class LEVELDB_EXPORT WritableFile { public: - WritableFile() { } + WritableFile() = default; + + WritableFile(const WritableFile&) = delete; + WritableFile& operator=(const WritableFile&) = delete; + virtual ~WritableFile(); virtual Status Append(const Slice& data) = 0; virtual Status Close() = 0; virtual Status Flush() = 0; virtual Status Sync() = 0; - - private: - // No copying allowed - WritableFile(const WritableFile&); - void operator=(const WritableFile&); }; // An interface for writing log messages. class LEVELDB_EXPORT Logger { public: - Logger() { } + Logger() = default; + + Logger(const Logger&) = delete; + Logger& operator=(const Logger&) = delete; + virtual ~Logger(); // Write an entry to the log file with the specified format. virtual void Logv(const char* format, va_list ap) = 0; - - private: - // No copying allowed - Logger(const Logger&); - void operator=(const Logger&); }; - // Identifies a locked file. class LEVELDB_EXPORT FileLock { public: - FileLock() { } + FileLock() = default; + + FileLock(const FileLock&) = delete; + FileLock& operator=(const FileLock&) = delete; + virtual ~FileLock(); - private: - // No copying allowed - FileLock(const FileLock&); - void operator=(const FileLock&); }; // Log the specified data to *info_log if info_log is non-NULL. @@ -290,61 +284,72 @@ LEVELDB_EXPORT Status ReadFileToString(Env* env, const std::string& fname, // functionality of another Env. class LEVELDB_EXPORT EnvWrapper : public Env { public: - // Initialize an EnvWrapper that delegates all calls to *t + // Initialize an EnvWrapper that delegates all calls to *t. explicit EnvWrapper(Env* t) : target_(t) { } virtual ~EnvWrapper(); - // Return the target to which this Env forwards all calls + // Return the target to which this Env forwards all calls. Env* target() const { return target_; } - // The following text is boilerplate that forwards all methods to target() - Status NewSequentialFile(const std::string& f, SequentialFile** r) { + // The following text is boilerplate that forwards all methods to target(). + Status NewSequentialFile(const std::string& f, SequentialFile** r) override { return target_->NewSequentialFile(f, r); } - Status NewRandomAccessFile(const std::string& f, RandomAccessFile** r) { + Status NewRandomAccessFile(const std::string& f, + RandomAccessFile** r) override { return target_->NewRandomAccessFile(f, r); } - Status NewWritableFile(const std::string& f, WritableFile** r) { + Status NewWritableFile(const std::string& f, WritableFile** r) override { return target_->NewWritableFile(f, r); } - Status NewAppendableFile(const std::string& f, WritableFile** r) { + Status NewAppendableFile(const std::string& f, WritableFile** r) override { return target_->NewAppendableFile(f, r); } - bool FileExists(const std::string& f) { return target_->FileExists(f); } - Status GetChildren(const std::string& dir, std::vector* r) { + bool FileExists(const std::string& f) override { + return target_->FileExists(f); + } + Status GetChildren(const std::string& dir, + std::vector* r) override { return target_->GetChildren(dir, r); } - Status DeleteFile(const std::string& f) { return target_->DeleteFile(f); } - Status CreateDir(const std::string& d) { return target_->CreateDir(d); } - Status DeleteDir(const std::string& d) { return target_->DeleteDir(d); } - Status GetFileSize(const std::string& f, uint64_t* s) { + Status DeleteFile(const std::string& f) override { + return target_->DeleteFile(f); + } + Status CreateDir(const std::string& d) override { + return target_->CreateDir(d); + } + Status DeleteDir(const std::string& d) override { + return target_->DeleteDir(d); + } + Status GetFileSize(const std::string& f, uint64_t* s) override { return target_->GetFileSize(f, s); } - Status RenameFile(const std::string& s, const std::string& t) { + Status RenameFile(const std::string& s, const std::string& t) override { return target_->RenameFile(s, t); } - Status LockFile(const std::string& f, FileLock** l) { + Status LockFile(const std::string& f, FileLock** l) override { return target_->LockFile(f, l); } - Status UnlockFile(FileLock* l) { return target_->UnlockFile(l); } - void Schedule(void (*f)(void*), void* a) { + Status UnlockFile(FileLock* l) override { return target_->UnlockFile(l); } + void Schedule(void (*f)(void*), void* a) override { return target_->Schedule(f, a); } - void StartThread(void (*f)(void*), void* a) { + void StartThread(void (*f)(void*), void* a) override { return target_->StartThread(f, a); } - virtual Status GetTestDirectory(std::string* path) { + Status GetTestDirectory(std::string* path) override { return target_->GetTestDirectory(path); } - virtual Status NewLogger(const std::string& fname, Logger** result) { + Status NewLogger(const std::string& fname, Logger** result) override { return target_->NewLogger(fname, result); } - uint64_t NowMicros() { + uint64_t NowMicros() override { return target_->NowMicros(); } - void SleepForMicroseconds(int micros) { + void SleepForMicroseconds(int micros) override { target_->SleepForMicroseconds(micros); } + private: Env* target_; }; diff --git a/include/leveldb/filter_policy.h b/include/leveldb/filter_policy.h index c3a5d20..ba02720 100644 --- a/include/leveldb/filter_policy.h +++ b/include/leveldb/filter_policy.h @@ -65,6 +65,7 @@ class LEVELDB_EXPORT FilterPolicy { // FilterPolicy (like NewBloomFilterPolicy) that does not ignore // trailing spaces in keys. LEVELDB_EXPORT const FilterPolicy* NewBloomFilterPolicy(int bits_per_key); -} + +} // namespace leveldb #endif // STORAGE_LEVELDB_INCLUDE_FILTER_POLICY_H_ diff --git a/include/leveldb/iterator.h b/include/leveldb/iterator.h index ff3b566..436508a 100644 --- a/include/leveldb/iterator.h +++ b/include/leveldb/iterator.h @@ -24,6 +24,10 @@ namespace leveldb { class LEVELDB_EXPORT Iterator { public: Iterator(); + + Iterator(const Iterator&) = delete; + Iterator& operator=(const Iterator&) = delete; + virtual ~Iterator(); // An iterator is either positioned at a key/value pair, or @@ -84,10 +88,6 @@ class LEVELDB_EXPORT Iterator { Cleanup* next; }; Cleanup cleanup_; - - // No copying allowed - Iterator(const Iterator&); - void operator=(const Iterator&); }; // Return an empty iterator (yields nothing). diff --git a/include/leveldb/slice.h b/include/leveldb/slice.h index b56a4e4..a86e8a6 100644 --- a/include/leveldb/slice.h +++ b/include/leveldb/slice.h @@ -37,6 +37,10 @@ class LEVELDB_EXPORT Slice { // Create a slice that refers to s[0,strlen(s)-1] Slice(const char* s) : data_(s), size_(strlen(s)) { } + // Intentionally copyable. + Slice(const Slice&) = default; + Slice& operator=(const Slice&) = default; + // Return a pointer to the beginning of the referenced data const char* data() const { return data_; } @@ -81,8 +85,6 @@ class LEVELDB_EXPORT Slice { private: const char* data_; size_t size_; - - // Intentionally copyable }; inline bool operator==(const Slice& x, const Slice& y) { diff --git a/include/leveldb/table.h b/include/leveldb/table.h index 2f54c4e..83078d2 100644 --- a/include/leveldb/table.h +++ b/include/leveldb/table.h @@ -41,6 +41,9 @@ class LEVELDB_EXPORT Table { uint64_t file_size, Table** table); + Table(const Table&) = delete; + void operator=(const Table&) = delete; + ~Table(); // Returns a new iterator over the table contents. @@ -75,10 +78,6 @@ class LEVELDB_EXPORT Table { void ReadMeta(const Footer& footer); void ReadFilter(const Slice& filter_handle_value); - - // No copying allowed - Table(const Table&); - void operator=(const Table&); }; } // namespace leveldb diff --git a/include/leveldb/table_builder.h b/include/leveldb/table_builder.h index 3c3acc7..8d05d33 100644 --- a/include/leveldb/table_builder.h +++ b/include/leveldb/table_builder.h @@ -31,6 +31,9 @@ class LEVELDB_EXPORT TableBuilder { // caller to close the file after calling Finish(). TableBuilder(const Options& options, WritableFile* file); + TableBuilder(const TableBuilder&) = delete; + void operator=(const TableBuilder&) = delete; + // REQUIRES: Either Finish() or Abandon() has been called. ~TableBuilder(); @@ -82,10 +85,6 @@ class LEVELDB_EXPORT TableBuilder { struct Rep; Rep* rep_; - - // No copying allowed - TableBuilder(const TableBuilder&); - void operator=(const TableBuilder&); }; } // namespace leveldb diff --git a/include/leveldb/write_batch.h b/include/leveldb/write_batch.h index 40ceb03..b6d72cb 100644 --- a/include/leveldb/write_batch.h +++ b/include/leveldb/write_batch.h @@ -32,6 +32,11 @@ class Slice; class LEVELDB_EXPORT WriteBatch { public: WriteBatch(); + + // Intentionally copyable. + WriteBatch(const WriteBatch&) = default; + WriteBatch& operator =(const WriteBatch&) = default; + ~WriteBatch(); // Store the mapping "key->value" in the database. @@ -62,8 +67,6 @@ class LEVELDB_EXPORT WriteBatch { friend class WriteBatchInternal; std::string rep_; // See comment in write_batch.cc for the format of rep_ - - // Intentionally copyable }; } // namespace leveldb