From 3725179736e2b5372664163470e7ef3dc76529a4 Mon Sep 17 00:00:00 2001 From: Sfan5 Date: Mon, 9 Sep 2013 22:46:18 +0200 Subject: Use system-wide LevelDB instead of bundled one --- src/leveldb/db/log_reader.cc | 259 ------------------------------------------- 1 file changed, 259 deletions(-) delete mode 100644 src/leveldb/db/log_reader.cc (limited to 'src/leveldb/db/log_reader.cc') diff --git a/src/leveldb/db/log_reader.cc b/src/leveldb/db/log_reader.cc deleted file mode 100644 index b35f115aa..000000000 --- a/src/leveldb/db/log_reader.cc +++ /dev/null @@ -1,259 +0,0 @@ -// Copyright (c) 2011 The LevelDB Authors. All rights reserved. -// Use of this source code is governed by a BSD-style license that can be -// found in the LICENSE file. See the AUTHORS file for names of contributors. - -#include "db/log_reader.h" - -#include -#include "leveldb/env.h" -#include "util/coding.h" -#include "util/crc32c.h" - -namespace leveldb { -namespace log { - -Reader::Reporter::~Reporter() { -} - -Reader::Reader(SequentialFile* file, Reporter* reporter, bool checksum, - uint64_t initial_offset) - : file_(file), - reporter_(reporter), - checksum_(checksum), - backing_store_(new char[kBlockSize]), - buffer_(), - eof_(false), - last_record_offset_(0), - end_of_buffer_offset_(0), - initial_offset_(initial_offset) { -} - -Reader::~Reader() { - delete[] backing_store_; -} - -bool Reader::SkipToInitialBlock() { - size_t offset_in_block = initial_offset_ % kBlockSize; - uint64_t block_start_location = initial_offset_ - offset_in_block; - - // Don't search a block if we'd be in the trailer - if (offset_in_block > kBlockSize - 6) { - offset_in_block = 0; - block_start_location += kBlockSize; - } - - end_of_buffer_offset_ = block_start_location; - - // Skip to start of first block that can contain the initial record - if (block_start_location > 0) { - Status skip_status = file_->Skip(block_start_location); - if (!skip_status.ok()) { - ReportDrop(block_start_location, skip_status); - return false; - } - } - - return true; -} - -bool Reader::ReadRecord(Slice* record, std::string* scratch) { - if (last_record_offset_ < initial_offset_) { - if (!SkipToInitialBlock()) { - return false; - } - } - - scratch->clear(); - record->clear(); - bool in_fragmented_record = false; - // Record offset of the logical record that we're reading - // 0 is a dummy value to make compilers happy - uint64_t prospective_record_offset = 0; - - Slice fragment; - while (true) { - uint64_t physical_record_offset = end_of_buffer_offset_ - buffer_.size(); - const unsigned int record_type = ReadPhysicalRecord(&fragment); - switch (record_type) { - case kFullType: - if (in_fragmented_record) { - // Handle bug in earlier versions of log::Writer where - // it could emit an empty kFirstType record at the tail end - // of a block followed by a kFullType or kFirstType record - // at the beginning of the next block. - if (scratch->empty()) { - in_fragmented_record = false; - } else { - ReportCorruption(scratch->size(), "partial record without end(1)"); - } - } - prospective_record_offset = physical_record_offset; - scratch->clear(); - *record = fragment; - last_record_offset_ = prospective_record_offset; - return true; - - case kFirstType: - if (in_fragmented_record) { - // Handle bug in earlier versions of log::Writer where - // it could emit an empty kFirstType record at the tail end - // of a block followed by a kFullType or kFirstType record - // at the beginning of the next block. - if (scratch->empty()) { - in_fragmented_record = false; - } else { - ReportCorruption(scratch->size(), "partial record without end(2)"); - } - } - prospective_record_offset = physical_record_offset; - scratch->assign(fragment.data(), fragment.size()); - in_fragmented_record = true; - break; - - case kMiddleType: - if (!in_fragmented_record) { - ReportCorruption(fragment.size(), - "missing start of fragmented record(1)"); - } else { - scratch->append(fragment.data(), fragment.size()); - } - break; - - case kLastType: - if (!in_fragmented_record) { - ReportCorruption(fragment.size(), - "missing start of fragmented record(2)"); - } else { - scratch->append(fragment.data(), fragment.size()); - *record = Slice(*scratch); - last_record_offset_ = prospective_record_offset; - return true; - } - break; - - case kEof: - if (in_fragmented_record) { - ReportCorruption(scratch->size(), "partial record without end(3)"); - scratch->clear(); - } - return false; - - case kBadRecord: - if (in_fragmented_record) { - ReportCorruption(scratch->size(), "error in middle of record"); - in_fragmented_record = false; - scratch->clear(); - } - break; - - default: { - char buf[40]; - snprintf(buf, sizeof(buf), "unknown record type %u", record_type); - ReportCorruption( - (fragment.size() + (in_fragmented_record ? scratch->size() : 0)), - buf); - in_fragmented_record = false; - scratch->clear(); - break; - } - } - } - return false; -} - -uint64_t Reader::LastRecordOffset() { - return last_record_offset_; -} - -void Reader::ReportCorruption(size_t bytes, const char* reason) { - ReportDrop(bytes, Status::Corruption(reason)); -} - -void Reader::ReportDrop(size_t bytes, const Status& reason) { - if (reporter_ != NULL && - end_of_buffer_offset_ - buffer_.size() - bytes >= initial_offset_) { - reporter_->Corruption(bytes, reason); - } -} - -unsigned int Reader::ReadPhysicalRecord(Slice* result) { - while (true) { - if (buffer_.size() < kHeaderSize) { - if (!eof_) { - // Last read was a full read, so this is a trailer to skip - buffer_.clear(); - Status status = file_->Read(kBlockSize, &buffer_, backing_store_); - end_of_buffer_offset_ += buffer_.size(); - if (!status.ok()) { - buffer_.clear(); - ReportDrop(kBlockSize, status); - eof_ = true; - return kEof; - } else if (buffer_.size() < kBlockSize) { - eof_ = true; - } - continue; - } else if (buffer_.size() == 0) { - // End of file - return kEof; - } else { - size_t drop_size = buffer_.size(); - buffer_.clear(); - ReportCorruption(drop_size, "truncated record at end of file"); - return kEof; - } - } - - // Parse the header - const char* header = buffer_.data(); - const uint32_t a = static_cast(header[4]) & 0xff; - const uint32_t b = static_cast(header[5]) & 0xff; - const unsigned int type = header[6]; - const uint32_t length = a | (b << 8); - if (kHeaderSize + length > buffer_.size()) { - size_t drop_size = buffer_.size(); - buffer_.clear(); - ReportCorruption(drop_size, "bad record length"); - return kBadRecord; - } - - if (type == kZeroType && length == 0) { - // Skip zero length record without reporting any drops since - // such records are produced by the mmap based writing code in - // env_posix.cc that preallocates file regions. - buffer_.clear(); - return kBadRecord; - } - - // Check crc - if (checksum_) { - uint32_t expected_crc = crc32c::Unmask(DecodeFixed32(header)); - uint32_t actual_crc = crc32c::Value(header + 6, 1 + length); - if (actual_crc != expected_crc) { - // Drop the rest of the buffer since "length" itself may have - // been corrupted and if we trust it, we could find some - // fragment of a real log record that just happens to look - // like a valid log record. - size_t drop_size = buffer_.size(); - buffer_.clear(); - ReportCorruption(drop_size, "checksum mismatch"); - return kBadRecord; - } - } - - buffer_.remove_prefix(kHeaderSize + length); - - // Skip physical record that started before initial_offset_ - if (end_of_buffer_offset_ - buffer_.size() - kHeaderSize - length < - initial_offset_) { - result->clear(); - return kBadRecord; - } - - *result = Slice(header + kHeaderSize, length); - return type; - } -} - -} // namespace log -} // namespace leveldb -- cgit v1.2.3