Fix write-ahead log file size overflow (#7870)

Summary:
The WAL's file size is stored as an unsigned 64 bit integer.

In db_info_dumper.cc, this integer gets converted to a string. Since 2^64 is approximately 10^19, we need 20 digits to represent the integer correctly. To store the decimal representation, we need 21 bytes (+1 due to the '\0' terminator at the end). The code previously used 16 bytes, which would overflow if the log is really big (>1 petabyte).

Pull Request resolved: https://github.com/facebook/rocksdb/pull/7870

Reviewed By: ajkr

Differential Revision: D25938776

Pulled By: jay-zhuang

fbshipit-source-id: 6ee9e21ebd65d297ea90fa1e7e74f3e1c533299d
This commit is contained in:
Vladimir Maksimovski 2021-01-19 13:46:03 -08:00 committed by Facebook GitHub Bot
parent 5b748b9e68
commit 4db58bcfb2

View File

@ -64,9 +64,10 @@ void DumpDBFileSummary(const ImmutableDBOptions& options,
break;
case kWalFile:
if (env->GetFileSize(dbname + "/" + file, &file_size).ok()) {
char str[16];
snprintf(str, sizeof(str), "%" PRIu64, file_size);
wal_info.append(file).append(" size: ").append(str).append(" ; ");
wal_info.append(file)
.append(" size: ")
.append(std::to_string(file_size))
.append(" ; ");
} else {
Error(options.info_log, "Error when reading LOG file: %s/%s\n",
dbname.c_str(), file.c_str());
@ -120,9 +121,10 @@ void DumpDBFileSummary(const ImmutableDBOptions& options,
if (ParseFileName(file, &number, &type)) {
if (type == kWalFile) {
if (env->GetFileSize(options.wal_dir + "/" + file, &file_size).ok()) {
char str[16];
snprintf(str, sizeof(str), "%" PRIu64, file_size);
wal_info.append(file).append(" size: ").append(str).append(" ; ");
wal_info.append(file)
.append(" size: ")
.append(std::to_string(file_size))
.append(" ; ");
} else {
Error(options.info_log, "Error when reading LOG file %s/%s\n",
options.wal_dir.c_str(), file.c_str());