| // Copyright (c) 2011 The LevelDB Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. See the AUTHORS file for names of contributors. |
| |
| #include <ctype.h> |
| #include <stdio.h> |
| #include "db/filename.h" |
| #include "db/dbformat.h" |
| #include "leveldb/env.h" |
| #include "util/logging.h" |
| |
| namespace leveldb { |
| |
| // A utility routine: write "data" to the named file and Sync() it. |
| extern Status WriteStringToFileSync(Env* env, const Slice& data, |
| const std::string& fname); |
| |
| static std::string MakeFileName(const std::string& name, uint64_t number, |
| const char* suffix) { |
| char buf[100]; |
| snprintf(buf, sizeof(buf), "/%06llu.%s", |
| static_cast<unsigned long long>(number), |
| suffix); |
| return name + buf; |
| } |
| |
| std::string LogFileName(const std::string& name, uint64_t number) { |
| assert(number > 0); |
| return MakeFileName(name, number, "log"); |
| } |
| |
| std::string TableFileName(const std::string& name, uint64_t number) { |
| assert(number > 0); |
| return MakeFileName(name, number, "sst"); |
| } |
| |
| std::string DescriptorFileName(const std::string& dbname, uint64_t number) { |
| assert(number > 0); |
| char buf[100]; |
| snprintf(buf, sizeof(buf), "/MANIFEST-%06llu", |
| static_cast<unsigned long long>(number)); |
| return dbname + buf; |
| } |
| |
| std::string CurrentFileName(const std::string& dbname) { |
| return dbname + "/CURRENT"; |
| } |
| |
| std::string LockFileName(const std::string& dbname) { |
| return dbname + "/LOCK"; |
| } |
| |
| std::string TempFileName(const std::string& dbname, uint64_t number) { |
| assert(number > 0); |
| return MakeFileName(dbname, number, "dbtmp"); |
| } |
| |
| std::string InfoLogFileName(const std::string& dbname) { |
| return dbname + "/LOG"; |
| } |
| |
| // Return the name of the old info log file for "dbname". |
| std::string OldInfoLogFileName(const std::string& dbname) { |
| return dbname + "/LOG.old"; |
| } |
| |
| |
| // Owned filenames have the form: |
| // dbname/CURRENT |
| // dbname/LOCK |
| // dbname/LOG |
| // dbname/LOG.old |
| // dbname/MANIFEST-[0-9]+ |
| // dbname/[0-9]+.(log|sst) |
| bool ParseFileName(const std::string& fname, |
| uint64_t* number, |
| FileType* type) { |
| Slice rest(fname); |
| if (rest == "CURRENT") { |
| *number = 0; |
| *type = kCurrentFile; |
| } else if (rest == "LOCK") { |
| *number = 0; |
| *type = kDBLockFile; |
| } else if (rest == "LOG" || rest == "LOG.old") { |
| *number = 0; |
| *type = kInfoLogFile; |
| } else if (rest.starts_with("MANIFEST-")) { |
| rest.remove_prefix(strlen("MANIFEST-")); |
| uint64_t num; |
| if (!ConsumeDecimalNumber(&rest, &num)) { |
| return false; |
| } |
| if (!rest.empty()) { |
| return false; |
| } |
| *type = kDescriptorFile; |
| *number = num; |
| } else { |
| // Avoid strtoull() to keep filename format independent of the |
| // current locale |
| uint64_t num; |
| if (!ConsumeDecimalNumber(&rest, &num)) { |
| return false; |
| } |
| Slice suffix = rest; |
| if (suffix == Slice(".log")) { |
| *type = kLogFile; |
| } else if (suffix == Slice(".sst")) { |
| *type = kTableFile; |
| } else if (suffix == Slice(".dbtmp")) { |
| *type = kTempFile; |
| } else { |
| return false; |
| } |
| *number = num; |
| } |
| return true; |
| } |
| |
| Status SetCurrentFile(Env* env, const std::string& dbname, |
| uint64_t descriptor_number) { |
| // Remove leading "dbname/" and add newline to manifest file name |
| std::string manifest = DescriptorFileName(dbname, descriptor_number); |
| Slice contents = manifest; |
| assert(contents.starts_with(dbname + "/")); |
| contents.remove_prefix(dbname.size() + 1); |
| std::string tmp = TempFileName(dbname, descriptor_number); |
| Status s = WriteStringToFileSync(env, contents.ToString() + "\n", tmp); |
| if (s.ok()) { |
| s = env->RenameFile(tmp, CurrentFileName(dbname)); |
| } |
| if (!s.ok()) { |
| env->DeleteFile(tmp); |
| } |
| return s; |
| } |
| |
| } // namespace leveldb |