dash/src/addrdb.cpp
Wladimir J. van der Laan d36a4a4db3
Merge #13039: Add logging and error handling for file syncing
cf02779 Add logging and error handling for file syncing (Wladimir J. van der Laan)

Pull request description:

  Add logging and error handling inside, and outside of FileCommit.
  Functions such as fsync, fdatasync will return error in case of hardware I/O errors, and ignoring this means it can silently continue through data corruption.
  (c.f. https://lwn.net/SubscriberLink/752063/12b232ab5039efbe/)

  EINVAL is handled specially to avoid crashing out on (network, fuse) filesystems that don't handle `f[data]sync`.

  I checked that the syncing inside leveldb is already generating an I/O error as appropriate.

Tree-SHA512: 64cc9bbedca3ecc97ff4bac0a7b7ac6526a7ed763c66f6786d03ca4f2e9e366e42b152cb908299c060448d98ca39ff03395280bffaca51d592e728aa2516f5dd
2020-11-17 14:32:37 -05:00

147 lines
3.9 KiB
C++

// Copyright (c) 2009-2010 Satoshi Nakamoto
// Copyright (c) 2009-2015 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 <addrdb.h>
#include <addrman.h>
#include <chainparams.h>
#include <clientversion.h>
#include <hash.h>
#include <random.h>
#include <streams.h>
#include <tinyformat.h>
#include <util.h>
namespace {
template <typename Stream, typename Data>
bool SerializeDB(Stream& stream, const Data& data)
{
// Write and commit header, data
try {
CHashWriter hasher(SER_DISK, CLIENT_VERSION);
stream << Params().MessageStart() << data;
hasher << Params().MessageStart() << data;
stream << hasher.GetHash();
} catch (const std::exception& e) {
return error("%s: Serialize or I/O error - %s", __func__, e.what());
}
return true;
}
template <typename Data>
bool SerializeFileDB(const std::string& prefix, const fs::path& path, const Data& data)
{
// Generate random temporary filename
unsigned short randv = 0;
GetRandBytes((unsigned char*)&randv, sizeof(randv));
std::string tmpfn = strprintf("%s.%04x", prefix, randv);
// open temp output file, and associate with CAutoFile
fs::path pathTmp = GetDataDir() / tmpfn;
FILE *file = fsbridge::fopen(pathTmp, "wb");
CAutoFile fileout(file, SER_DISK, CLIENT_VERSION);
if (fileout.IsNull())
return error("%s: Failed to open file %s", __func__, pathTmp.string());
// Serialize
if (!SerializeDB(fileout, data)) return false;
if (!FileCommit(fileout.Get()))
return error("%s: Failed to flush file %s", __func__, pathTmp.string());
fileout.fclose();
// replace existing file, if any, with new file
if (!RenameOver(pathTmp, path))
return error("%s: Rename-into-place failed", __func__);
return true;
}
template <typename Stream, typename Data>
bool DeserializeDB(Stream& stream, Data& data, bool fCheckSum = true)
{
try {
CHashVerifier<Stream> verifier(&stream);
// de-serialize file header (network specific magic number) and ..
unsigned char pchMsgTmp[4];
verifier >> pchMsgTmp;
// ... verify the network matches ours
if (memcmp(pchMsgTmp, Params().MessageStart(), sizeof(pchMsgTmp)))
return error("%s: Invalid network magic number", __func__);
// de-serialize data
verifier >> data;
// verify checksum
if (fCheckSum) {
uint256 hashTmp;
stream >> hashTmp;
if (hashTmp != verifier.GetHash()) {
return error("%s: Checksum mismatch, data corrupted", __func__);
}
}
}
catch (const std::exception& e) {
return error("%s: Deserialize or I/O error - %s", __func__, e.what());
}
return true;
}
template <typename Data>
bool DeserializeFileDB(const fs::path& path, Data& data)
{
// open input file, and associate with CAutoFile
FILE *file = fsbridge::fopen(path, "rb");
CAutoFile filein(file, SER_DISK, CLIENT_VERSION);
if (filein.IsNull())
return error("%s: Failed to open file %s", __func__, path.string());
return DeserializeDB(filein, data);
}
}
CBanDB::CBanDB()
{
pathBanlist = GetDataDir() / "banlist.dat";
}
bool CBanDB::Write(const banmap_t& banSet)
{
return SerializeFileDB("banlist", pathBanlist, banSet);
}
bool CBanDB::Read(banmap_t& banSet)
{
return DeserializeFileDB(pathBanlist, banSet);
}
CAddrDB::CAddrDB()
{
pathAddr = GetDataDir() / "peers.dat";
}
bool CAddrDB::Write(const CAddrMan& addr)
{
return SerializeFileDB("peers", pathAddr, addr);
}
bool CAddrDB::Read(CAddrMan& addr)
{
return DeserializeFileDB(pathAddr, addr);
}
bool CAddrDB::Read(CAddrMan& addr, CDataStream& ssPeers)
{
bool ret = DeserializeDB(ssPeers, addr, false);
if (!ret) {
// Ensure addrman is left in a clean state
addr.Clear();
}
return ret;
}