lbrycrd/src/dbwrapper.cpp
Hennadii Stepanov a0a222eec0
Replace deprecated Boost Filesystem function
Boost Filesystem basename() function is deprecated since v1.36.0.
Also, defining BOOST_FILESYSTEM_NO_DEPRECATED before including
filesystem headers is strongly recommended. This prevents inadvertent
use of old features, particularly legacy function names, that have been
replaced and are going to go away in the future.
2019-04-30 10:05:54 +03:00

258 lines
8.8 KiB
C++

// Copyright (c) 2012-2018 The Bitcoin Core developers
// Distributed under the MIT software license, see the accompanying
// file COPYING or http://www.opensource.org/licenses/mit-license.php.
#include <dbwrapper.h>
#include <memory>
#include <random.h>
#include <leveldb/cache.h>
#include <leveldb/env.h>
#include <leveldb/filter_policy.h>
#include <memenv.h>
#include <stdint.h>
#include <algorithm>
class CBitcoinLevelDBLogger : public leveldb::Logger {
public:
// This code is adapted from posix_logger.h, which is why it is using vsprintf.
// Please do not do this in normal code
void Logv(const char * format, va_list ap) override {
if (!LogAcceptCategory(BCLog::LEVELDB)) {
return;
}
char buffer[500];
for (int iter = 0; iter < 2; iter++) {
char* base;
int bufsize;
if (iter == 0) {
bufsize = sizeof(buffer);
base = buffer;
}
else {
bufsize = 30000;
base = new char[bufsize];
}
char* p = base;
char* limit = base + bufsize;
// Print the message
if (p < limit) {
va_list backup_ap;
va_copy(backup_ap, ap);
// Do not use vsnprintf elsewhere in bitcoin source code, see above.
p += vsnprintf(p, limit - p, format, backup_ap);
va_end(backup_ap);
}
// Truncate to available space if necessary
if (p >= limit) {
if (iter == 0) {
continue; // Try again with larger buffer
}
else {
p = limit - 1;
}
}
// Add newline if necessary
if (p == base || p[-1] != '\n') {
*p++ = '\n';
}
assert(p <= limit);
base[std::min(bufsize - 1, (int)(p - base))] = '\0';
LogPrintf("leveldb: %s", base); /* Continued */
if (base != buffer) {
delete[] base;
}
break;
}
}
};
static void SetMaxOpenFiles(leveldb::Options *options) {
// On most platforms the default setting of max_open_files (which is 1000)
// is optimal. On Windows using a large file count is OK because the handles
// do not interfere with select() loops. On 64-bit Unix hosts this value is
// also OK, because up to that amount LevelDB will use an mmap
// implementation that does not use extra file descriptors (the fds are
// closed after being mmap'ed).
//
// Increasing the value beyond the default is dangerous because LevelDB will
// fall back to a non-mmap implementation when the file count is too large.
// On 32-bit Unix host we should decrease the value because the handles use
// up real fds, and we want to avoid fd exhaustion issues.
//
// See PR #12495 for further discussion.
int default_open_files = options->max_open_files;
#ifndef WIN32
if (sizeof(void*) < 8) {
options->max_open_files = 64;
}
#endif
LogPrint(BCLog::LEVELDB, "LevelDB using max_open_files=%d (default=%d)\n",
options->max_open_files, default_open_files);
}
static leveldb::Options GetOptions(size_t nCacheSize)
{
leveldb::Options options;
options.block_cache = leveldb::NewLRUCache(nCacheSize / 2);
options.write_buffer_size = nCacheSize / 4; // up to two write buffers may be held in memory simultaneously
options.filter_policy = leveldb::NewBloomFilterPolicy(10);
options.compression = leveldb::kNoCompression;
options.info_log = new CBitcoinLevelDBLogger();
if (leveldb::kMajorVersion > 1 || (leveldb::kMajorVersion == 1 && leveldb::kMinorVersion >= 16)) {
// LevelDB versions before 1.16 consider short writes to be corruption. Only trigger error
// on corruption in later versions.
options.paranoid_checks = true;
}
SetMaxOpenFiles(&options);
return options;
}
CDBWrapper::CDBWrapper(const fs::path& path, size_t nCacheSize, bool fMemory, bool fWipe, bool obfuscate)
: m_name{path.stem().string()}
{
penv = nullptr;
readoptions.verify_checksums = true;
iteroptions.verify_checksums = true;
iteroptions.fill_cache = false;
syncoptions.sync = true;
options = GetOptions(nCacheSize);
options.create_if_missing = true;
if (fMemory) {
penv = leveldb::NewMemEnv(leveldb::Env::Default());
options.env = penv;
} else {
if (fWipe) {
LogPrintf("Wiping LevelDB in %s\n", path.string());
leveldb::Status result = leveldb::DestroyDB(path.string(), options);
dbwrapper_private::HandleError(result);
}
TryCreateDirectories(path);
LogPrintf("Opening LevelDB in %s\n", path.string());
}
leveldb::Status status = leveldb::DB::Open(options, path.string(), &pdb);
dbwrapper_private::HandleError(status);
LogPrintf("Opened LevelDB successfully\n");
if (gArgs.GetBoolArg("-forcecompactdb", false)) {
LogPrintf("Starting database compaction of %s\n", path.string());
pdb->CompactRange(nullptr, nullptr);
LogPrintf("Finished database compaction of %s\n", path.string());
}
// The base-case obfuscation key, which is a noop.
obfuscate_key = std::vector<unsigned char>(OBFUSCATE_KEY_NUM_BYTES, '\000');
bool key_exists = Read(OBFUSCATE_KEY_KEY, obfuscate_key);
if (!key_exists && obfuscate && IsEmpty()) {
// Initialize non-degenerate obfuscation if it won't upset
// existing, non-obfuscated data.
std::vector<unsigned char> new_key = CreateObfuscateKey();
// Write `new_key` so we don't obfuscate the key with itself
Write(OBFUSCATE_KEY_KEY, new_key);
obfuscate_key = new_key;
LogPrintf("Wrote new obfuscate key for %s: %s\n", path.string(), HexStr(obfuscate_key));
}
LogPrintf("Using obfuscation key for %s: %s\n", path.string(), HexStr(obfuscate_key));
}
CDBWrapper::~CDBWrapper()
{
delete pdb;
pdb = nullptr;
delete options.filter_policy;
options.filter_policy = nullptr;
delete options.info_log;
options.info_log = nullptr;
delete options.block_cache;
options.block_cache = nullptr;
delete penv;
options.env = nullptr;
}
bool CDBWrapper::WriteBatch(CDBBatch& batch, bool fSync)
{
const bool log_memory = LogAcceptCategory(BCLog::LEVELDB);
double mem_before = 0;
if (log_memory) {
mem_before = DynamicMemoryUsage() / 1024.0 / 1024;
}
leveldb::Status status = pdb->Write(fSync ? syncoptions : writeoptions, &batch.batch);
dbwrapper_private::HandleError(status);
if (log_memory) {
double mem_after = DynamicMemoryUsage() / 1024.0 / 1024;
LogPrint(BCLog::LEVELDB, "WriteBatch memory usage: db=%s, before=%.1fMiB, after=%.1fMiB\n",
m_name, mem_before, mem_after);
}
return true;
}
size_t CDBWrapper::DynamicMemoryUsage() const {
std::string memory;
if (!pdb->GetProperty("leveldb.approximate-memory-usage", &memory)) {
LogPrint(BCLog::LEVELDB, "Failed to get approximate-memory-usage property\n");
return 0;
}
return stoul(memory);
}
// Prefixed with null character to avoid collisions with other keys
//
// We must use a string constructor which specifies length so that we copy
// past the null-terminator.
const std::string CDBWrapper::OBFUSCATE_KEY_KEY("\000obfuscate_key", 14);
const unsigned int CDBWrapper::OBFUSCATE_KEY_NUM_BYTES = 8;
/**
* Returns a string (consisting of 8 random bytes) suitable for use as an
* obfuscating XOR key.
*/
std::vector<unsigned char> CDBWrapper::CreateObfuscateKey() const
{
unsigned char buff[OBFUSCATE_KEY_NUM_BYTES];
GetRandBytes(buff, OBFUSCATE_KEY_NUM_BYTES);
return std::vector<unsigned char>(&buff[0], &buff[OBFUSCATE_KEY_NUM_BYTES]);
}
bool CDBWrapper::IsEmpty()
{
std::unique_ptr<CDBIterator> it(NewIterator());
it->SeekToFirst();
return !(it->Valid());
}
CDBIterator::~CDBIterator() { delete piter; }
bool CDBIterator::Valid() const { return piter->Valid(); }
void CDBIterator::SeekToFirst() { piter->SeekToFirst(); }
void CDBIterator::Next() { piter->Next(); }
namespace dbwrapper_private {
void HandleError(const leveldb::Status& status)
{
if (status.ok())
return;
const std::string errmsg = "Fatal LevelDB error: " + status.ToString();
LogPrintf("%s\n", errmsg);
LogPrintf("You can use -debug=leveldb to get more complete diagnostic messages\n");
throw dbwrapper_error(errmsg);
}
const std::vector<unsigned char>& GetObfuscateKey(const CDBWrapper &w)
{
return w.obfuscate_key;
}
} // namespace dbwrapper_private