删除了些没用的修改

db/dbformat.cc

@@ -12,14 +12,13 @@
 
 namespace leveldb {
 
-static uint64_t PackSequenceAndTypeAndTtlAndLookup(
-                      uint64_t seq, ValueType t, bool havettl, bool islookup) {
+static uint64_t PackSequenceAndTypeAndTtl(
+                      uint64_t seq, ValueType t, bool havettl) {
   assert(seq <= kMaxSequenceNumber);
   assert(t <= kValueTypeForSeek);
-  return (seq << 8) | (islookup << 2) | (havettl << 1) | t;
+  return (seq << 8) | (havettl << 1) | t;
 }
 
-//下面有两个调这个函数的没改，也许也要修改标志位？
 static uint64_t PackSequenceAndType(uint64_t seq, ValueType t) {
   assert(seq <= kMaxSequenceNumber);
   assert(t <= kValueTypeForSeek);
@@ -30,8 +29,8 @@ void AppendInternalKey(std::string* result, const ParsedInternalKey& key) {
   result->append(key.user_key.data(), key.user_key.size());
   if(key.deadTime != 0)
     PutFixed64(result, key.deadTime);
-  PutFixed64(result, PackSequenceAndTypeAndTtlAndLookup(
-                                key.sequence, key.type, (key.deadTime != 0), false));
+  PutFixed64(result, PackSequenceAndTypeAndTtl(
+                                key.sequence, key.type, (key.deadTime != 0)));
 }
 
 std::string ParsedInternalKey::DebugString() const {
@@ -164,10 +163,10 @@ LookupKey::LookupKey(const Slice& user_key, SequenceNumber s, uint64_t nowTime)
   EncodeFixed64(dst, nowTime);
   dst += 8;
   // EncodeFixed64(dst, PackSequenceAndTypeAndTtlAndLookup(s, kValueTypeForSeek, 0, true));
-  EncodeFixed64(dst, PackSequenceAndTypeAndTtlAndLookup(s, kValueTypeForSeek, 1, false));
+  EncodeFixed64(dst, PackSequenceAndTypeAndTtl(s, kValueTypeForSeek, 1));
   dst += 8;
   end_ = dst;
-  printf("lookupkey tag:%lx\n",PackSequenceAndTypeAndTtlAndLookup(s, kValueTypeForSeek, 1, false));
+  printf("lookupkey tag:%lx\n",PackSequenceAndTypeAndTtl(s, kValueTypeForSeek, 1));
 }
 
 }  // namespace leveldb

db/dbformat.h

@@ -102,9 +102,8 @@ inline Slice ExtractUserKey(const Slice& internal_key) {
   assert(internal_key.size() >= 8);
   uint64_t num = DecodeFixed64(internal_key.data() + internal_key.size() - 8);
   uint8_t havettl = (num & 0b10) >> 1;
-  uint8_t islookup = (num & 0b100) >> 2;
   size_t klen = internal_key.size() - 8;
-  if(havettl || islookup)  klen -= 8;
+  if(havettl)  klen -= 8;
   Slice user_key = Slice(internal_key.data(), klen);
   return user_key;
 }
@@ -183,7 +182,6 @@ inline int InternalKeyComparator::Compare(const InternalKey& a,
 
 inline bool ParseInternalKey(const Slice& internal_key,
                              ParsedInternalKey* result) {
-                              //不确定需不需要标识islookup，先没改
   const size_t n = internal_key.size();
   if (n < 8) return false;
   uint64_t tag = DecodeFixed64(internal_key.data() + n - 8);
@@ -228,10 +226,8 @@ class LookupKey {
   //    klength  varint32               <-- start_
   //    userkey  char[klength]          <-- kstart_
   //    nowTime  uint64
-  //    tag      uint64 最后一个字节为0000 0101
+  //    tag      uint64 最后一个字节为0000 0001
   //                                    <-- end_
-  //    同userkey下，原本（insert时）的比较器规则为seq优先，不考虑时间
-  //    新增标识位（tag倒数第三位），使比较器考虑时间
   // The array is a suitable MemTable key.
   // The suffix starting with "userkey" can be used as an InternalKey.
   const char* start_;

db/memtable.cc

@@ -187,18 +187,6 @@ bool MemTable::Get(const LookupKey& key, std::string* value, Status* s) {
       const uint64_t tag = DecodeFixed64(key_ptr + key_length - 8);
       switch (static_cast<ValueType>(tag & 0x01)) {
         case kTypeValue: {
-          // uint8_t havettl = (tag & 0xff) >> 1;
-          // if(havettl){
-          //     time_t nowTime;
-          //     time(&nowTime);
-          //     assert(nowTime > 0);
-          //     const uint64_t deadTime = DecodeFixed64(key_ptr + key_length - 16);
-          //     if(static_cast<uint64_t>(nowTime) >= deadTime){ //过期了
-          //       std::cout << nowTime << "dead:" << deadTime << std::endl;
-          //       *s = Status::NotFound(Slice());
-          //       return true; //todo:之前有没过期的key
-          //     }
-          // }
           Slice v = GetLengthPrefixedSlice(key_ptr + key_length);
           value->assign(v.data(), v.size());
           return true;

test/db_test2.cc

@@ -23,7 +23,7 @@ Status OpenDB(std::string dbName, DB **db) {
 void InsertData(DB *db) {
   WriteOptions writeOptions;
   int key_num = data_size / value_size;
-  srand(static_cast<unsigned int>(time(0)));
+  srand(0);
 
   for (int i = 0; i < key_num; i++) {
     int key_ = rand() % key_num+1;
@@ -39,7 +39,7 @@ void GetData(DB *db, int size = (1 << 30)) {
   int key_num = data_size / value_size;
   
   // 点查
-  srand(static_cast<unsigned int>(time(0)));
+  srand(0);
   for (int i = 0; i < 100; i++) {
     int key_ = rand() % key_num+1;
     std::string key = std::to_string(key_);

test/ttl_mmtable_test.cc

@@ -1,113 +0,0 @@
-#include "leveldb/env.h"
-#include "leveldb/db.h"
-#include "ctime"
-#include <iostream>
-#include <cstdlib>
-#include "gtest/gtest.h"
-
-using namespace leveldb;
-
-constexpr int value_size = 2048;
-constexpr int data_size = 2048 << 15;
-
-Status OpenDB(std::string dbName, DB **db) {
-  Options options;
-  options.create_if_missing = true;
-  return DB::Open(options, dbName, db);
-}
-
-void InsertData(DB *db, uint64_t ttl/* second */, int vsize = 1/*插不同长度的value*/) {
-  printf("-----inserting-----\n");
-  Status status;
-  WriteOptions writeOptions;
-  int key_num = data_size / value_size;
-  srand(static_cast<unsigned int>(time(0)));
-
-  for (int i = 0; i < key_num; i++) {
-    //int key_ = rand() % key_num+1;
-    int key_ = i+1;
-    std::string key = std::to_string(key_);
-    std::string value(vsize, 'a');
-    status = db->Put(writeOptions, key, value, ttl);
-    assert(status.ok());
-  }
-}
-
-void GetData(DB *db, bool isTimeout) {
-  printf("-----seeking-----\n");
-  ReadOptions readOptions;
-  Status status;
-  int key_num = data_size / value_size;
-  srand(static_cast<unsigned int>(time(0)));
-  for (int i = 0; i < key_num; i++) {
-      //int key_ = rand() % key_num+1;
-      int key_ = i+1;
-      std::string key = std::to_string(key_);
-      std::string value;
-      status = db->Get(readOptions, key, &value);
-      if(isTimeout)   assert(status.IsNotFound());
-      else{
-        assert(status.ok());
-        std::cout << value << std::endl;
-      }
-  }
-}
-
-void TimeOut() {
-DB *db;
-  printf("-----opening-----\n");
-  if(OpenDB("testdb", &db).ok() == false) {
-      std::cerr << "open db failed" << std::endl;
-      abort();
-  }
-
-  uint64_t ttl = 3;
-
-  InsertData(db, ttl);
-  GetData(db, false);
-
-  Env::Default()->SleepForMicroseconds(ttl * 1000000);
-  GetData(db, true);
-
-  delete(db);
-  printf("-----closing-----\n");
-
-  // printf("-----recovery-----\n");
-  // if(OpenDB("testdb", &db).ok() == false) {
-  //     std::cerr << "open db failed" << std::endl;
-  //     abort();
-  // }
-  // GetData(db, true);
-  printf("success!\n");
-}
-
-void GetEarlierData() {
-DB *db;
-  printf("-----opening-----\n");
-  if(OpenDB("testdb", &db).ok() == false) {
-      std::cerr << "open db failed" << std::endl;
-      abort();
-  }
-
-  uint64_t ttl1 = 3;
-  uint64_t ttl2 = 5;
-
-  // InsertData(db, ttl2);
-  InsertData(db, ttl1, 2);
-
-  //都没过期先找到后插的
-  Env::Default()->SleepForMicroseconds(1 * 1000000);
-  GetData(db, false);
-  
-  //再找到前一次
-  Env::Default()->SleepForMicroseconds(3 * 1000000);
-  GetData(db, true);
-  DestroyDB("testdb",Options());
-  delete(db);
-  printf("-----closing-----\n");
-  printf("success!\n");
-}
-
-int main(int argc, char** argv) {
-  GetEarlierData();
-}