rocksdb/utilities/blob_db/blob_dump_tool.cc
Mike Kolupaev 397ab11152 Improve Status message for block checksum mismatches
Summary:
We've got some DBs where iterators return Status with message "Corruption: block checksum mismatch" all the time. That's not very informative. It would be much easier to investigate if the error message contained the file name - then we would know e.g. how old the corrupted file is, which would be very useful for finding the root cause. This PR adds file name, offset and other stuff to some block corruption-related status messages.

It doesn't improve all the error messages, just a few that were easy to improve. I'm mostly interested in "block checksum mismatch" and "Bad table magic number" since they're the only corruption errors that I've ever seen in the wild.
Closes https://github.com/facebook/rocksdb/pull/2507

Differential Revision: D5345702

Pulled By: al13n321

fbshipit-source-id: fc8023d43f1935ad927cef1b9c55481ab3cb1339
2017-06-28 21:27:01 -07:00

261 lines
8.2 KiB
C++

// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under the BSD-style license found in the
// LICENSE file in the root directory of this source tree. An additional grant
// of patent rights can be found in the PATENTS file in the same directory.
// This source code is also licensed under the GPLv2 license found in the
// COPYING file in the root directory of this source tree.
#ifndef ROCKSDB_LITE
#ifndef __STDC_FORMAT_MACROS
#define __STDC_FORMAT_MACROS
#endif
#include "utilities/blob_db/blob_dump_tool.h"
#include <inttypes.h>
#include <stdio.h>
#include <iostream>
#include <memory>
#include <string>
#include "port/port.h"
#include "rocksdb/convenience.h"
#include "rocksdb/env.h"
#include "util/coding.h"
#include "util/crc32c.h"
#include "util/string_util.h"
namespace rocksdb {
namespace blob_db {
BlobDumpTool::BlobDumpTool()
: reader_(nullptr), buffer_(nullptr), buffer_size_(0) {}
Status BlobDumpTool::Run(const std::string& filename, DisplayType show_key,
DisplayType show_blob) {
Status s;
Env* env = Env::Default();
s = env->FileExists(filename);
if (!s.ok()) {
return s;
}
uint64_t file_size = 0;
s = env->GetFileSize(filename, &file_size);
if (!s.ok()) {
return s;
}
std::unique_ptr<RandomAccessFile> file;
s = env->NewRandomAccessFile(filename, &file, EnvOptions());
if (!s.ok()) {
return s;
}
if (file_size == 0) {
return Status::Corruption("File is empty.");
}
reader_.reset(new RandomAccessFileReader(std::move(file), filename));
uint64_t offset = 0;
uint64_t footer_offset = 0;
s = DumpBlobLogHeader(&offset);
if (!s.ok()) {
return s;
}
s = DumpBlobLogFooter(file_size, &footer_offset);
if (!s.ok()) {
return s;
}
if (show_key != DisplayType::kNone) {
while (offset < footer_offset) {
s = DumpRecord(show_key, show_blob, &offset);
if (!s.ok()) {
return s;
}
}
}
return s;
}
Status BlobDumpTool::Read(uint64_t offset, size_t size, Slice* result) {
if (buffer_size_ < size) {
if (buffer_size_ == 0) {
buffer_size_ = 4096;
}
while (buffer_size_ < size) {
buffer_size_ *= 2;
}
buffer_.reset(new char[buffer_size_]);
}
Status s = reader_->Read(offset, size, result, buffer_.get());
if (!s.ok()) {
return s;
}
if (result->size() != size) {
return Status::Corruption("Reach the end of the file unexpectedly.");
}
return s;
}
Status BlobDumpTool::DumpBlobLogHeader(uint64_t* offset) {
Slice slice;
Status s = Read(0, BlobLogHeader::kHeaderSize, &slice);
if (!s.ok()) {
return s;
}
BlobLogHeader header;
s = header.DecodeFrom(slice);
if (!s.ok()) {
return s;
}
fprintf(stdout, "Blob log header:\n");
fprintf(stdout, " Magic Number : %u\n", header.magic_number());
fprintf(stdout, " Version : %d\n", header.version());
CompressionType compression = header.compression();
std::string compression_str;
if (!GetStringFromCompressionType(&compression_str, compression).ok()) {
compression_str = "Unrecongnized compression type (" +
ToString((int)header.compression()) + ")";
}
fprintf(stdout, " Compression : %s\n", compression_str.c_str());
fprintf(stdout, " TTL Range : %s\n",
GetString(header.ttl_range()).c_str());
fprintf(stdout, " Timestamp Range: %s\n",
GetString(header.ts_range()).c_str());
*offset = BlobLogHeader::kHeaderSize;
return s;
}
Status BlobDumpTool::DumpBlobLogFooter(uint64_t file_size,
uint64_t* footer_offset) {
auto no_footer = [&]() {
*footer_offset = file_size;
fprintf(stdout, "No blob log footer.\n");
return Status::OK();
};
if (file_size < BlobLogHeader::kHeaderSize + BlobLogFooter::kFooterSize) {
return no_footer();
}
Slice slice;
Status s = Read(file_size - 4, 4, &slice);
if (!s.ok()) {
return s;
}
uint32_t magic_number = DecodeFixed32(slice.data());
if (magic_number != kMagicNumber) {
return no_footer();
}
*footer_offset = file_size - BlobLogFooter::kFooterSize;
s = Read(*footer_offset, BlobLogFooter::kFooterSize, &slice);
if (!s.ok()) {
return s;
}
BlobLogFooter footer;
s = footer.DecodeFrom(slice);
if (!s.ok()) {
return s;
}
fprintf(stdout, "Blob log footer:\n");
fprintf(stdout, " Blob count : %" PRIu64 "\n", footer.GetBlobCount());
fprintf(stdout, " TTL Range : %s\n",
GetString(footer.GetTTLRange()).c_str());
fprintf(stdout, " Time Range : %s\n",
GetString(footer.GetTimeRange()).c_str());
fprintf(stdout, " Sequence Range : %s\n",
GetString(footer.GetSNRange()).c_str());
return s;
}
Status BlobDumpTool::DumpRecord(DisplayType show_key, DisplayType show_blob,
uint64_t* offset) {
fprintf(stdout, "Read record with offset 0x%" PRIx64 " (%" PRIu64 "):\n",
*offset, *offset);
Slice slice;
Status s = Read(*offset, BlobLogRecord::kHeaderSize, &slice);
if (!s.ok()) {
return s;
}
BlobLogRecord record;
s = record.DecodeHeaderFrom(slice);
if (!s.ok()) {
return s;
}
uint32_t key_size = record.GetKeySize();
uint64_t blob_size = record.GetBlobSize();
fprintf(stdout, " key size : %d\n", key_size);
fprintf(stdout, " blob size : %" PRIu64 "\n", record.GetBlobSize());
fprintf(stdout, " TTL : %u\n", record.GetTTL());
fprintf(stdout, " time : %" PRIu64 "\n", record.GetTimeVal());
fprintf(stdout, " type : %d, %d\n", record.type(), record.subtype());
fprintf(stdout, " header CRC : %u\n", record.header_checksum());
fprintf(stdout, " CRC : %u\n", record.checksum());
uint32_t header_crc =
crc32c::Extend(0, slice.data(), slice.size() - 2 * sizeof(uint32_t));
*offset += BlobLogRecord::kHeaderSize;
s = Read(*offset, key_size + blob_size + BlobLogRecord::kFooterSize, &slice);
if (!s.ok()) {
return s;
}
header_crc = crc32c::Extend(header_crc, slice.data(), key_size);
header_crc = crc32c::Mask(header_crc);
if (header_crc != record.header_checksum()) {
return Status::Corruption("Record header checksum mismatch.");
}
uint32_t blob_crc = crc32c::Extend(0, slice.data() + key_size, blob_size);
blob_crc = crc32c::Mask(blob_crc);
if (blob_crc != record.checksum()) {
return Status::Corruption("Blob checksum mismatch.");
}
if (show_key != DisplayType::kNone) {
fprintf(stdout, " key : ");
DumpSlice(Slice(slice.data(), key_size), show_key);
if (show_blob != DisplayType::kNone) {
fprintf(stdout, " blob : ");
DumpSlice(Slice(slice.data() + key_size, blob_size), show_blob);
}
}
Slice footer_slice(slice.data() + record.GetKeySize() + record.GetBlobSize(),
BlobLogRecord::kFooterSize);
s = record.DecodeFooterFrom(footer_slice);
if (!s.ok()) {
return s;
}
fprintf(stdout, " footer CRC : %u\n", record.footer_checksum());
fprintf(stdout, " sequence : %" PRIu64 "\n", record.GetSN());
*offset += key_size + blob_size + BlobLogRecord::kFooterSize;
return s;
}
void BlobDumpTool::DumpSlice(const Slice s, DisplayType type) {
if (type == DisplayType::kRaw) {
fprintf(stdout, "%s\n", s.ToString().c_str());
} else if (type == DisplayType::kHex) {
fprintf(stdout, "%s\n", s.ToString(true /*hex*/).c_str());
} else if (type == DisplayType::kDetail) {
char buf[100];
for (size_t i = 0; i < s.size(); i += 16) {
memset(buf, 0, sizeof(buf));
for (size_t j = 0; j < 16 && i + j < s.size(); j++) {
unsigned char c = s[i + j];
snprintf(buf + j * 3 + 15, 2, "%x", c >> 4);
snprintf(buf + j * 3 + 16, 2, "%x", c & 0xf);
snprintf(buf + j + 65, 2, "%c", (0x20 <= c && c <= 0x7e) ? c : '.');
}
for (size_t p = 0; p < sizeof(buf) - 1; p++) {
if (buf[p] == 0) {
buf[p] = ' ';
}
}
fprintf(stdout, "%s\n", i == 0 ? buf + 15 : buf);
}
}
}
template <class T>
std::string BlobDumpTool::GetString(std::pair<T, T> p) {
if (p.first == 0 && p.second == 0) {
return "nil";
}
return "(" + ToString(p.first) + ", " + ToString(p.second) + ")";
}
} // namespace blob_db
} // namespace rocksdb
#endif // ROCKSDB_LITE