rocksdb/tools/ldb_cmd_test.cc

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// Copyright (c) 2011-present, Facebook, Inc. All rights reserved.
// This source code is licensed under both the GPLv2 (found in the
// COPYING file in the root directory) and Apache 2.0 License
// (found in the LICENSE.Apache file in the root directory).
//
#ifndef ROCKSDB_LITE
#include "rocksdb/utilities/ldb_cmd.h"
#include "db/version_edit.h"
#include "db/version_set.h"
Introduce a new storage specific Env API (#5761) Summary: The current Env API encompasses both storage/file operations, as well as OS related operations. Most of the APIs return a Status, which does not have enough metadata about an error, such as whether its retry-able or not, scope (i.e fault domain) of the error etc., that may be required in order to properly handle a storage error. The file APIs also do not provide enough control over the IO SLA, such as timeout, prioritization, hinting about placement and redundancy etc. This PR separates out the file/storage APIs from Env into a new FileSystem class. The APIs are updated to return an IOStatus with metadata about the error, as well as to take an IOOptions structure as input in order to allow more control over the IO. The user can set both ```options.env``` and ```options.file_system``` to specify that RocksDB should use the former for OS related operations and the latter for storage operations. Internally, a ```CompositeEnvWrapper``` has been introduced that inherits from ```Env``` and redirects individual methods to either an ```Env``` implementation or the ```FileSystem``` as appropriate. When options are sanitized during ```DB::Open```, ```options.env``` is replaced with a newly allocated ```CompositeEnvWrapper``` instance if both env and file_system have been specified. This way, the rest of the RocksDB code can continue to function as before. This PR also ports PosixEnv to the new API by splitting it into two - PosixEnv and PosixFileSystem. PosixEnv is defined as a sub-class of CompositeEnvWrapper, and threading/time functions are overridden with Posix specific implementations in order to avoid an extra level of indirection. The ```CompositeEnvWrapper``` translates ```IOStatus``` return code to ```Status```, and sets the severity to ```kSoftError``` if the io_status is retryable. The error handling code in RocksDB can then recover the DB automatically. Pull Request resolved: https://github.com/facebook/rocksdb/pull/5761 Differential Revision: D18868376 Pulled By: anand1976 fbshipit-source-id: 39efe18a162ea746fabac6360ff529baba48486f
2019-12-13 23:47:08 +01:00
#include "env/composite_env_wrapper.h"
#include "file/filename.h"
#include "port/stack_trace.h"
#include "rocksdb/file_checksum.h"
#include "test_util/sync_point.h"
#include "test_util/testharness.h"
#include "test_util/testutil.h"
#include "util/file_checksum_helper.h"
using std::string;
using std::vector;
using std::map;
namespace ROCKSDB_NAMESPACE {
class LdbCmdTest : public testing::Test {
public:
LdbCmdTest() : testing::Test() {}
Env* TryLoadCustomOrDefaultEnv() {
const char* test_env_uri = getenv("TEST_ENV_URI");
if (!test_env_uri) {
return Env::Default();
}
Env* env = Env::Default();
Env::LoadEnv(test_env_uri, &env, &env_guard_);
return env;
}
private:
std::shared_ptr<Env> env_guard_;
};
TEST_F(LdbCmdTest, HexToString) {
// map input to expected outputs.
// odd number of "hex" half bytes doesn't make sense
map<string, vector<int>> inputMap = {
{"0x07", {7}}, {"0x5050", {80, 80}}, {"0xFF", {-1}},
{"0x1234", {18, 52}}, {"0xaaAbAC", {-86, -85, -84}}, {"0x1203", {18, 3}},
};
for (const auto& inPair : inputMap) {
auto actual = ROCKSDB_NAMESPACE::LDBCommand::HexToString(inPair.first);
auto expected = inPair.second;
for (unsigned int i = 0; i < actual.length(); i++) {
EXPECT_EQ(expected[i], static_cast<int>((signed char) actual[i]));
}
auto reverse = ROCKSDB_NAMESPACE::LDBCommand::StringToHex(actual);
EXPECT_STRCASEEQ(inPair.first.c_str(), reverse.c_str());
}
}
TEST_F(LdbCmdTest, HexToStringBadInputs) {
const vector<string> badInputs = {
"0xZZ", "123", "0xx5", "0x111G", "0x123", "Ox12", "0xT", "0x1Q1",
};
for (const auto badInput : badInputs) {
try {
ROCKSDB_NAMESPACE::LDBCommand::HexToString(badInput);
std::cerr << "Should fail on bad hex value: " << badInput << "\n";
FAIL();
} catch (...) {
}
}
}
TEST_F(LdbCmdTest, MemEnv) {
Env* base_env = TryLoadCustomOrDefaultEnv();
std::unique_ptr<Env> env(NewMemEnv(base_env));
Options opts;
opts.env = env.get();
opts.create_if_missing = true;
DB* db = nullptr;
std::string dbname = test::TmpDir();
ASSERT_OK(DB::Open(opts, dbname, &db));
WriteOptions wopts;
for (int i = 0; i < 100; i++) {
char buf[16];
snprintf(buf, sizeof(buf), "%08d", i);
ASSERT_OK(db->Put(wopts, buf, buf));
}
FlushOptions fopts;
fopts.wait = true;
ASSERT_OK(db->Flush(fopts));
delete db;
char arg1[] = "./ldb";
char arg2[1024];
snprintf(arg2, sizeof(arg2), "--db=%s", dbname.c_str());
char arg3[] = "dump_live_files";
char* argv[] = {arg1, arg2, arg3};
ASSERT_EQ(0,
LDBCommandRunner::RunCommand(3, argv, opts, LDBOptions(), nullptr));
}
class FileChecksumTestHelper {
private:
Options options_;
DB* db_;
std::string dbname_;
Status VerifyChecksum(LiveFileMetaData& file_meta) {
std::string cur_checksum;
std::string checksum_func_name;
Status s;
EnvOptions soptions;
std::unique_ptr<SequentialFile> file_reader;
std::string file_path = dbname_ + "/" + file_meta.name;
s = options_.env->NewSequentialFile(file_path, &file_reader, soptions);
if (!s.ok()) {
return s;
}
std::unique_ptr<char[]> scratch(new char[2048]);
Slice result;
FileChecksumGenFactory* file_checksum_gen_factory =
options_.file_checksum_gen_factory.get();
if (file_checksum_gen_factory == nullptr) {
cur_checksum = kUnknownFileChecksum;
checksum_func_name = kUnknownFileChecksumFuncName;
} else {
FileChecksumGenContext gen_context;
gen_context.file_name = file_meta.name;
std::unique_ptr<FileChecksumGenerator> file_checksum_gen =
file_checksum_gen_factory->CreateFileChecksumGenerator(gen_context);
checksum_func_name = file_checksum_gen->Name();
s = file_reader->Read(2048, &result, scratch.get());
if (!s.ok()) {
return s;
}
while (result.size() != 0) {
file_checksum_gen->Update(scratch.get(), result.size());
s = file_reader->Read(2048, &result, scratch.get());
if (!s.ok()) {
return s;
}
}
file_checksum_gen->Finalize();
cur_checksum = file_checksum_gen->GetChecksum();
}
std::string stored_checksum = file_meta.file_checksum;
std::string stored_checksum_func_name = file_meta.file_checksum_func_name;
if ((cur_checksum != stored_checksum) ||
(checksum_func_name != stored_checksum_func_name)) {
return Status::Corruption(
"Checksum does not match! The file: " + file_meta.name +
", checksum name: " + stored_checksum_func_name + " and checksum " +
stored_checksum + ". However, expected checksum name: " +
checksum_func_name + " and checksum " + cur_checksum);
}
return Status::OK();
}
public:
FileChecksumTestHelper(Options& options, DB* db, std::string db_name)
: options_(options), db_(db), dbname_(db_name) {}
~FileChecksumTestHelper() {}
// Verify the checksum information in Manifest.
Status VerifyChecksumInManifest(
const std::vector<LiveFileMetaData>& live_files) {
// Step 1: verify if the dbname_ is correct
if (dbname_[dbname_.length() - 1] != '/') {
dbname_.append("/");
}
// Step 2, get the the checksum information by recovering the VersionSet
// from Manifest.
std::unique_ptr<FileChecksumList> checksum_list(NewFileChecksumList());
EnvOptions sopt;
std::shared_ptr<Cache> tc(NewLRUCache(options_.max_open_files - 10,
options_.table_cache_numshardbits));
options_.db_paths.emplace_back(dbname_, 0);
options_.num_levels = 64;
WriteController wc(options_.delayed_write_rate);
WriteBufferManager wb(options_.db_write_buffer_size);
ImmutableDBOptions immutable_db_options(options_);
VersionSet versions(dbname_, &immutable_db_options, sopt, tc.get(), &wb,
&wc, nullptr);
std::vector<std::string> cf_name_list;
Status s;
s = versions.ListColumnFamilies(&cf_name_list, dbname_,
Simplify migration to FileSystem API (#6552) Summary: The current Env/FileSystem API separation has a couple of issues - 1. It requires the user to specify 2 options - ```Options::env``` and ```Options::file_system``` - which means they have to make code changes to benefit from the new APIs. Furthermore, there is a risk of accessing the same APIs in two different ways, through Env in the old way and through FileSystem in the new way. The two may not always match, for example, if env is ```PosixEnv``` and FileSystem is a custom implementation. Any stray RocksDB calls to env will use the ```PosixEnv``` implementation rather than the file_system implementation. 2. There needs to be a simple way for the FileSystem developer to instantiate an Env for backward compatibility purposes. This PR solves the above issues and simplifies the migration in the following ways - 1. Embed a shared_ptr to the ```FileSystem``` in the ```Env```, and remove ```Options::file_system``` as a configurable option. This way, no code changes will be required in application code to benefit from the new API. The default Env constructor uses a ```LegacyFileSystemWrapper``` as the embedded ```FileSystem```. 1a. - This also makes it more robust by ensuring that even if RocksDB has some stray calls to Env APIs rather than FileSystem, they will go through the same object and thus there is no risk of getting out of sync. 2. Provide a ```NewCompositeEnv()``` API that can be used to construct a PosixEnv with a custom FileSystem implementation. This eliminates an indirection to call Env APIs, and relieves the FileSystem developer of the burden of having to implement wrappers for the Env APIs. 3. Add a couple of missing FileSystem APIs - ```SanitizeEnvOptions()``` and ```NewLogger()``` Tests: 1. New unit tests 2. make check and make asan_check Pull Request resolved: https://github.com/facebook/rocksdb/pull/6552 Reviewed By: riversand963 Differential Revision: D20592038 Pulled By: anand1976 fbshipit-source-id: c3801ad4153f96d21d5a3ae26c92ba454d1bf1f7
2020-03-24 05:50:42 +01:00
immutable_db_options.fs.get());
if (s.ok()) {
std::vector<ColumnFamilyDescriptor> cf_list;
for (const auto& name : cf_name_list) {
fprintf(stdout, "cf_name: %s", name.c_str());
cf_list.emplace_back(name, ColumnFamilyOptions(options_));
}
s = versions.Recover(cf_list, true);
}
if (s.ok()) {
s = versions.GetLiveFilesChecksumInfo(checksum_list.get());
}
if (!s.ok()) {
return s;
}
// Step 3 verify the checksum
if (live_files.size() != checksum_list->size()) {
return Status::Corruption("The number of files does not match!");
}
for (size_t i = 0; i < live_files.size(); i++) {
std::string stored_checksum = "";
std::string stored_func_name = "";
s = checksum_list->SearchOneFileChecksum(
live_files[i].file_number, &stored_checksum, &stored_func_name);
if (s.IsNotFound()) {
return s;
}
if (live_files[i].file_checksum != stored_checksum ||
live_files[i].file_checksum_func_name != stored_func_name) {
return Status::Corruption(
"Checksum does not match! The file: " +
ToString(live_files[i].file_number) +
". In Manifest, checksum name: " + stored_func_name +
" and checksum " + stored_checksum +
". However, expected checksum name: " +
live_files[i].file_checksum_func_name + " and checksum " +
live_files[i].file_checksum);
}
}
return Status::OK();
}
// Verify the checksum of each file by recalculting the checksum and
// comparing it with the one being generated when a SST file is created.
Status VerifyEachFileChecksum() {
assert(db_ != nullptr);
std::vector<LiveFileMetaData> live_files;
db_->GetLiveFilesMetaData(&live_files);
for (auto a_file : live_files) {
Status cs = VerifyChecksum(a_file);
if (!cs.ok()) {
return cs;
}
}
return Status::OK();
}
};
TEST_F(LdbCmdTest, DumpFileChecksumNoChecksum) {
Env* base_env = TryLoadCustomOrDefaultEnv();
std::unique_ptr<Env> env(NewMemEnv(base_env));
Options opts;
opts.env = env.get();
opts.create_if_missing = true;
DB* db = nullptr;
std::string dbname = test::TmpDir();
ASSERT_OK(DB::Open(opts, dbname, &db));
WriteOptions wopts;
FlushOptions fopts;
fopts.wait = true;
Random rnd(test::RandomSeed());
for (int i = 0; i < 200; i++) {
char buf[16];
snprintf(buf, sizeof(buf), "%08d", i);
std::string v;
test::RandomString(&rnd, 100, &v);
ASSERT_OK(db->Put(wopts, buf, v));
}
ASSERT_OK(db->Flush(fopts));
for (int i = 100; i < 300; i++) {
char buf[16];
snprintf(buf, sizeof(buf), "%08d", i);
std::string v;
test::RandomString(&rnd, 100, &v);
ASSERT_OK(db->Put(wopts, buf, v));
}
ASSERT_OK(db->Flush(fopts));
for (int i = 200; i < 400; i++) {
char buf[16];
snprintf(buf, sizeof(buf), "%08d", i);
std::string v;
test::RandomString(&rnd, 100, &v);
ASSERT_OK(db->Put(wopts, buf, v));
}
ASSERT_OK(db->Flush(fopts));
for (int i = 300; i < 400; i++) {
char buf[16];
snprintf(buf, sizeof(buf), "%08d", i);
std::string v;
test::RandomString(&rnd, 100, &v);
ASSERT_OK(db->Put(wopts, buf, v));
}
ASSERT_OK(db->Flush(fopts));
char arg1[] = "./ldb";
char arg2[1024];
snprintf(arg2, sizeof(arg2), "--db=%s", dbname.c_str());
char arg3[] = "file_checksum_dump";
char* argv[] = {arg1, arg2, arg3};
ASSERT_EQ(0,
LDBCommandRunner::RunCommand(3, argv, opts, LDBOptions(), nullptr));
// Verify each sst file checksum value and checksum name
FileChecksumTestHelper fct_helper(opts, db, dbname);
ASSERT_OK(fct_helper.VerifyEachFileChecksum());
// Manually trigger compaction
char b_buf[16];
snprintf(b_buf, sizeof(b_buf), "%08d", 0);
char e_buf[16];
snprintf(e_buf, sizeof(e_buf), "%08d", 399);
Slice begin(b_buf);
Slice end(e_buf);
CompactRangeOptions options;
ASSERT_OK(db->CompactRange(options, &begin, &end));
// Verify each sst file checksum after compaction
FileChecksumTestHelper fct_helper_ac(opts, db, dbname);
ASSERT_OK(fct_helper_ac.VerifyEachFileChecksum());
ASSERT_EQ(0,
LDBCommandRunner::RunCommand(3, argv, opts, LDBOptions(), nullptr));
// Verify the checksum information in memory is the same as that in Manifest;
std::vector<LiveFileMetaData> live_files;
db->GetLiveFilesMetaData(&live_files);
delete db;
ASSERT_OK(fct_helper_ac.VerifyChecksumInManifest(live_files));
}
TEST_F(LdbCmdTest, DumpFileChecksumCRC32) {
Env* base_env = TryLoadCustomOrDefaultEnv();
std::unique_ptr<Env> env(NewMemEnv(base_env));
Options opts;
opts.env = env.get();
opts.create_if_missing = true;
opts.file_checksum_gen_factory = GetFileChecksumGenCrc32cFactory();
DB* db = nullptr;
std::string dbname = test::TmpDir();
ASSERT_OK(DB::Open(opts, dbname, &db));
WriteOptions wopts;
FlushOptions fopts;
fopts.wait = true;
Random rnd(test::RandomSeed());
for (int i = 0; i < 100; i++) {
char buf[16];
snprintf(buf, sizeof(buf), "%08d", i);
std::string v;
test::RandomString(&rnd, 100, &v);
ASSERT_OK(db->Put(wopts, buf, v));
}
ASSERT_OK(db->Flush(fopts));
for (int i = 50; i < 150; i++) {
char buf[16];
snprintf(buf, sizeof(buf), "%08d", i);
std::string v;
test::RandomString(&rnd, 100, &v);
ASSERT_OK(db->Put(wopts, buf, v));
}
ASSERT_OK(db->Flush(fopts));
for (int i = 100; i < 200; i++) {
char buf[16];
snprintf(buf, sizeof(buf), "%08d", i);
std::string v;
test::RandomString(&rnd, 100, &v);
ASSERT_OK(db->Put(wopts, buf, v));
}
ASSERT_OK(db->Flush(fopts));
for (int i = 150; i < 250; i++) {
char buf[16];
snprintf(buf, sizeof(buf), "%08d", i);
std::string v;
test::RandomString(&rnd, 100, &v);
ASSERT_OK(db->Put(wopts, buf, v));
}
ASSERT_OK(db->Flush(fopts));
char arg1[] = "./ldb";
char arg2[1024];
snprintf(arg2, sizeof(arg2), "--db=%s", dbname.c_str());
char arg3[] = "file_checksum_dump";
char* argv[] = {arg1, arg2, arg3};
ASSERT_EQ(0,
LDBCommandRunner::RunCommand(3, argv, opts, LDBOptions(), nullptr));
// Verify each sst file checksum value and checksum name
FileChecksumTestHelper fct_helper(opts, db, dbname);
ASSERT_OK(fct_helper.VerifyEachFileChecksum());
// Manually trigger compaction
char b_buf[16];
snprintf(b_buf, sizeof(b_buf), "%08d", 0);
char e_buf[16];
snprintf(e_buf, sizeof(e_buf), "%08d", 249);
Slice begin(b_buf);
Slice end(e_buf);
CompactRangeOptions options;
ASSERT_OK(db->CompactRange(options, &begin, &end));
// Verify each sst file checksum after compaction
FileChecksumTestHelper fct_helper_ac(opts, db, dbname);
ASSERT_OK(fct_helper_ac.VerifyEachFileChecksum());
ASSERT_EQ(0,
LDBCommandRunner::RunCommand(3, argv, opts, LDBOptions(), nullptr));
// Verify the checksum information in memory is the same as that in Manifest;
std::vector<LiveFileMetaData> live_files;
db->GetLiveFilesMetaData(&live_files);
delete db;
ASSERT_OK(fct_helper_ac.VerifyChecksumInManifest(live_files));
}
TEST_F(LdbCmdTest, OptionParsing) {
// test parsing flags
Options opts;
opts.env = TryLoadCustomOrDefaultEnv();
{
std::vector<std::string> args;
args.push_back("scan");
args.push_back("--ttl");
args.push_back("--timestamp");
LDBCommand* command = ROCKSDB_NAMESPACE::LDBCommand::InitFromCmdLineArgs(
args, opts, LDBOptions(), nullptr);
const std::vector<std::string> flags = command->TEST_GetFlags();
EXPECT_EQ(flags.size(), 2);
EXPECT_EQ(flags[0], "ttl");
EXPECT_EQ(flags[1], "timestamp");
delete command;
}
// test parsing options which contains equal sign in the option value
{
std::vector<std::string> args;
args.push_back("scan");
args.push_back("--db=/dev/shm/ldbtest/");
args.push_back(
"--from='abcd/efg/hijk/lmn/"
"opq:__rst.uvw.xyz?a=3+4+bcd+efghi&jk=lm_no&pq=rst-0&uv=wx-8&yz=a&bcd_"
"ef=gh.ijk'");
LDBCommand* command = ROCKSDB_NAMESPACE::LDBCommand::InitFromCmdLineArgs(
args, opts, LDBOptions(), nullptr);
const std::map<std::string, std::string> option_map =
command->TEST_GetOptionMap();
EXPECT_EQ(option_map.at("db"), "/dev/shm/ldbtest/");
EXPECT_EQ(option_map.at("from"),
"'abcd/efg/hijk/lmn/"
"opq:__rst.uvw.xyz?a=3+4+bcd+efghi&jk=lm_no&pq=rst-0&uv=wx-8&yz="
"a&bcd_ef=gh.ijk'");
delete command;
}
}
TEST_F(LdbCmdTest, ListFileTombstone) {
Env* base_env = TryLoadCustomOrDefaultEnv();
std::unique_ptr<Env> env(NewMemEnv(base_env));
Options opts;
opts.env = env.get();
opts.create_if_missing = true;
DB* db = nullptr;
std::string dbname = test::TmpDir();
ASSERT_OK(DB::Open(opts, dbname, &db));
WriteOptions wopts;
ASSERT_OK(db->Put(wopts, "foo", "1"));
ASSERT_OK(db->Put(wopts, "bar", "2"));
FlushOptions fopts;
fopts.wait = true;
ASSERT_OK(db->Flush(fopts));
ASSERT_OK(db->DeleteRange(wopts, db->DefaultColumnFamily(), "foo", "foo2"));
ASSERT_OK(db->DeleteRange(wopts, db->DefaultColumnFamily(), "bar", "foo2"));
ASSERT_OK(db->Flush(fopts));
delete db;
{
char arg1[] = "./ldb";
char arg2[1024];
snprintf(arg2, sizeof(arg2), "--db=%s", dbname.c_str());
char arg3[] = "list_file_range_deletes";
char* argv[] = {arg1, arg2, arg3};
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->SetCallBack(
"ListFileRangeDeletesCommand::DoCommand:BeforePrint", [&](void* arg) {
std::string* out_str = reinterpret_cast<std::string*>(arg);
// Count number of tombstones printed
int num_tb = 0;
const std::string kFingerprintStr = "start: ";
auto offset = out_str->find(kFingerprintStr);
while (offset != std::string::npos) {
num_tb++;
offset =
out_str->find(kFingerprintStr, offset + kFingerprintStr.size());
}
EXPECT_EQ(2, num_tb);
});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->EnableProcessing();
ASSERT_EQ(
0, LDBCommandRunner::RunCommand(3, argv, opts, LDBOptions(), nullptr));
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->ClearAllCallBacks();
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->DisableProcessing();
}
// Test the case of limiting tombstones
{
char arg1[] = "./ldb";
char arg2[1024];
snprintf(arg2, sizeof(arg2), "--db=%s", dbname.c_str());
char arg3[] = "list_file_range_deletes";
char arg4[] = "--max_keys=1";
char* argv[] = {arg1, arg2, arg3, arg4};
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->SetCallBack(
"ListFileRangeDeletesCommand::DoCommand:BeforePrint", [&](void* arg) {
std::string* out_str = reinterpret_cast<std::string*>(arg);
// Count number of tombstones printed
int num_tb = 0;
const std::string kFingerprintStr = "start: ";
auto offset = out_str->find(kFingerprintStr);
while (offset != std::string::npos) {
num_tb++;
offset =
out_str->find(kFingerprintStr, offset + kFingerprintStr.size());
}
EXPECT_EQ(1, num_tb);
});
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->EnableProcessing();
ASSERT_EQ(
0, LDBCommandRunner::RunCommand(4, argv, opts, LDBOptions(), nullptr));
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->ClearAllCallBacks();
ROCKSDB_NAMESPACE::SyncPoint::GetInstance()->DisableProcessing();
}
}
} // namespace ROCKSDB_NAMESPACE
#ifdef ROCKSDB_UNITTESTS_WITH_CUSTOM_OBJECTS_FROM_STATIC_LIBS
extern "C" {
void RegisterCustomObjects(int argc, char** argv);
}
#else
void RegisterCustomObjects(int /*argc*/, char** /*argv*/) {}
#endif // !ROCKSDB_UNITTESTS_WITH_CUSTOM_OBJECTS_FROM_STATIC_LIBS
int main(int argc, char** argv) {
ROCKSDB_NAMESPACE::port::InstallStackTraceHandler();
::testing::InitGoogleTest(&argc, argv);
RegisterCustomObjects(argc, argv);
return RUN_ALL_TESTS();
}
#else
#include <stdio.h>
int main(int /*argc*/, char** /*argv*/) {
fprintf(stderr, "SKIPPED as LDBCommand is not supported in ROCKSDB_LITE\n");
return 0;
}
#endif // ROCKSDB_LITE