Upgrade LevelDB to 1.10.0, mostly for better write stall logging.

src/cpp/leveldb/db/db_impl.cc

@@ -310,16 +310,24 @@ Status DBImpl::Recover(VersionEdit* edit) {
     if (!s.ok()) {
       return s;
     }
+    std::set<uint64_t> expected;
+    versions_->AddLiveFiles(&expected);
     uint64_t number;
     FileType type;
     std::vector<uint64_t> logs;
     for (size_t i = 0; i < filenames.size(); i++) {
-      if (ParseFileName(filenames[i], &number, &type)
-          && type == kLogFile
-          && ((number >= min_log) || (number == prev_log))) {
+      if (ParseFileName(filenames[i], &number, &type)) {
+        expected.erase(number);
+        if (type == kLogFile && ((number >= min_log) || (number == prev_log)))
         logs.push_back(number);
       }
     }
+    if (!expected.empty()) {
+      char buf[50];
+      snprintf(buf, sizeof(buf), "%d missing files; e.g.",
+               static_cast<int>(expected.size()));
+      return Status::Corruption(buf, TableFileName(dbname_, *(expected.begin())));
+    }
 
     // Recover in the order in which the logs were generated
     std::sort(logs.begin(), logs.end());
@@ -1268,10 +1276,11 @@ Status DBImpl::MakeRoomForWrite(bool force) {
     } else if (imm_ != NULL) {
       // We have filled up the current memtable, but the previous
       // one is still being compacted, so we wait.
+      Log(options_.info_log, "Current memtable full; waiting...\n");
       bg_cv_.Wait();
     } else if (versions_->NumLevelFiles(0) >= config::kL0_StopWritesTrigger) {
       // There are too many level-0 files.
-      Log(options_.info_log, "waiting...\n");
+      Log(options_.info_log, "Too many L0 files; waiting...\n");
       bg_cv_.Wait();
     } else {
       // Attempt to switch to a new memtable and trigger compaction of old

src/cpp/leveldb/db/db_test.cc

@@ -461,6 +461,20 @@ class DBTest {
     }
     return result;
   }
+
+  bool DeleteAnSSTFile() {
+    std::vector<std::string> filenames;
+    ASSERT_OK(env_->GetChildren(dbname_, &filenames));
+    uint64_t number;
+    FileType type;
+    for (size_t i = 0; i < filenames.size(); i++) {
+      if (ParseFileName(filenames[i], &number, &type) && type == kTableFile) {
+        ASSERT_OK(env_->DeleteFile(TableFileName(dbname_, number)));
+        return true;
+      }
+    }
+    return false;
+  }
 };
 
 TEST(DBTest, Empty) {
@@ -1567,6 +1581,23 @@ TEST(DBTest, ManifestWriteError) {
   }
 }
 
+TEST(DBTest, MissingSSTFile) {
+  ASSERT_OK(Put("foo", "bar"));
+  ASSERT_EQ("bar", Get("foo"));
+
+  // Dump the memtable to disk.
+  dbfull()->TEST_CompactMemTable();
+  ASSERT_EQ("bar", Get("foo"));
+
+  ASSERT_TRUE(DeleteAnSSTFile());
+  Options options = CurrentOptions();
+  options.paranoid_checks = true;
+  Status s = TryReopen(&options);
+  ASSERT_TRUE(!s.ok());
+  ASSERT_TRUE(s.ToString().find("issing") != std::string::npos)
+      << s.ToString();
+}
+
 TEST(DBTest, FilesDeletedAfterCompaction) {
   ASSERT_OK(Put("foo", "v2"));
   Compact("a", "z");

src/cpp/leveldb/db/dbformat.cc

@@ -26,7 +26,7 @@ std::string ParsedInternalKey::DebugString() const {
            (unsigned long long) sequence,
            int(type));
   std::string result = "'";
-  result += user_key.ToString();
+  result += EscapeString(user_key.ToString());
   result += buf;
   return result;
 }

src/cpp/leveldb/include/leveldb/db.h

@@ -14,7 +14,7 @@ namespace leveldb {
 
 // Update Makefile if you change these
 static const int kMajorVersion = 1;
-static const int kMinorVersion = 9;
+static const int kMinorVersion = 10;
 
 struct Options;
 struct ReadOptions;

src/cpp/leveldb/table/block.cc

@@ -16,7 +16,7 @@
 namespace leveldb {
 
 inline uint32_t Block::NumRestarts() const {
-  assert(size_ >= 2*sizeof(uint32_t));
+  assert(size_ >= sizeof(uint32_t));
   return DecodeFixed32(data_ + size_ - sizeof(uint32_t));
 }
 
@@ -27,11 +27,12 @@ Block::Block(const BlockContents& contents)
   if (size_ < sizeof(uint32_t)) {
     size_ = 0;  // Error marker
   } else {
-    restart_offset_ = size_ - (1 + NumRestarts()) * sizeof(uint32_t);
-    if (restart_offset_ > size_ - sizeof(uint32_t)) {
-      // The size is too small for NumRestarts() and therefore
-      // restart_offset_ wrapped around.
+    size_t max_restarts_allowed = (size_-sizeof(uint32_t)) / sizeof(uint32_t);
+    if (NumRestarts() > max_restarts_allowed) {
+      // The size is too small for NumRestarts()
       size_ = 0;
+    } else {
+      restart_offset_ = size_ - (1 + NumRestarts()) * sizeof(uint32_t);
     }
   }
 }
@@ -253,7 +254,7 @@ class Block::Iter : public Iterator {
 };
 
 Iterator* Block::NewIterator(const Comparator* cmp) {
-  if (size_ < 2*sizeof(uint32_t)) {
+  if (size_ < sizeof(uint32_t)) {
     return NewErrorIterator(Status::Corruption("bad block contents"));
   }
   const uint32_t num_restarts = NumRestarts();

src/cpp/leveldb/table/table.cc

@@ -228,7 +228,6 @@ Status Table::InternalGet(const ReadOptions& options, const Slice& k,
         !filter->KeyMayMatch(handle.offset(), k)) {
       // Not found
     } else {
-      Slice handle = iiter->value();
       Iterator* block_iter = BlockReader(this, options, iiter->value());
       block_iter->Seek(k);
       if (block_iter->Valid()) {

src/cpp/leveldb/table/table_test.cc

@@ -644,6 +644,36 @@ class Harness {
   Constructor* constructor_;
 };
 
+// Test empty table/block.
+TEST(Harness, Empty) {
+  for (int i = 0; i < kNumTestArgs; i++) {
+    Init(kTestArgList[i]);
+    Random rnd(test::RandomSeed() + 1);
+    Test(&rnd);
+  }
+}
+
+// Special test for a block with no restart entries.  The C++ leveldb
+// code never generates such blocks, but the Java version of leveldb
+// seems to.
+TEST(Harness, ZeroRestartPointsInBlock) {
+  char data[sizeof(uint32_t)];
+  memset(data, 0, sizeof(data));
+  BlockContents contents;
+  contents.data = Slice(data, sizeof(data));
+  contents.cachable = false;
+  contents.heap_allocated = false;
+  Block block(contents);
+  Iterator* iter = block.NewIterator(BytewiseComparator());
+  iter->SeekToFirst();
+  ASSERT_TRUE(!iter->Valid());
+  iter->SeekToLast();
+  ASSERT_TRUE(!iter->Valid());
+  iter->Seek("foo");
+  ASSERT_TRUE(!iter->Valid());
+  delete iter;
+}
+
 // Test the empty key
 TEST(Harness, SimpleEmptyKey) {
   for (int i = 0; i < kNumTestArgs; i++) {

src/cpp/leveldb/util/cache.cc

@@ -116,7 +116,6 @@ class HandleTable {
       LRUHandle* h = list_[i];
       while (h != NULL) {
         LRUHandle* next = h->next_hash;
-        Slice key = h->key();
         uint32_t hash = h->hash;
         LRUHandle** ptr = &new_list[hash & (new_length - 1)];
         h->next_hash = *ptr;
@@ -160,7 +159,6 @@ class LRUCache {
   // mutex_ protects the following state.
   port::Mutex mutex_;
   size_t usage_;
-  uint64_t last_id_;
 
   // Dummy head of LRU list.
   // lru.prev is newest entry, lru.next is oldest entry.
@@ -170,8 +168,7 @@ class LRUCache {
 };
 
 LRUCache::LRUCache()
-    : usage_(0),
-      last_id_(0) {
+    : usage_(0) {
   // Make empty circular linked list
   lru_.next = &lru_;
   lru_.prev = &lru_;

src/cpp/leveldb/util/env_posix.cc

@@ -386,7 +386,7 @@ class PosixEnv : public Env {
   PosixEnv();
   virtual ~PosixEnv() {
     fprintf(stderr, "Destroying Env::Default()\n");
-    exit(1);
+    abort();
   }
 
   virtual Status NewSequentialFile(const std::string& fname,
@@ -589,7 +589,7 @@ class PosixEnv : public Env {
   void PthreadCall(const char* label, int result) {
     if (result != 0) {
       fprintf(stderr, "pthread %s: %s\n", label, strerror(result));
-      exit(1);
+      abort();
     }
   }
 

src/cpp/leveldb/util/hash.cc

@@ -6,6 +6,13 @@
 #include "util/coding.h"
 #include "util/hash.h"
 
+// The FALLTHROUGH_INTENDED macro can be used to annotate implicit fall-through
+// between switch labels. The real definition should be provided externally.
+// This one is a fallback version for unsupported compilers.
+#ifndef FALLTHROUGH_INTENDED
+#define FALLTHROUGH_INTENDED do { } while (0)
+#endif
+
 namespace leveldb {
 
 uint32_t Hash(const char* data, size_t n, uint32_t seed) {
@@ -28,10 +35,10 @@ uint32_t Hash(const char* data, size_t n, uint32_t seed) {
   switch (limit - data) {
     case 3:
       h += data[2] << 16;
-      // fall through
+      FALLTHROUGH_INTENDED;
     case 2:
       h += data[1] << 8;
-      // fall through
+      FALLTHROUGH_INTENDED;
     case 1:
       h += data[0];
       h *= m;