Add support for plain table format to sst_dump.

Summary:
This diff enables the command line tool `sst_dump` to work for sst files
under plain table format.  Changes include:
  * In tools/sst_dump.cc:
    - add support for plain table format
    - display prefix_extractor information when --show_properties is on
  * In table/format.cc
    - Now the table magic number of a Footer can be later initialized
      via ReadFooterFromFile().
  * In table/meta_bocks:
    - add function ReadTableMagicNumber() that reads the magic number of
      the specified file.

Minor fixes:
 - remove a duplicate #include in table/table_test.cc
 - fix a commentary typo in include/rocksdb/memtablerep.h
 - fix lint errors.

Test Plan:
Runs sst_dump with both block-based and plain-table format files with
different arguments, specifically those with --show-properties and --from.

* sample output:
  https://reviews.facebook.net/P261

Reviewers: kailiu, sdong, xjin

CC: leveldb

Differential Revision: https://reviews.facebook.net/D15903

include/rocksdb/memtablerep.h

@@ -21,7 +21,7 @@
 // types built in:
 //  - SkipListRep: This is the default; it is backed by a skip list.
 //  - HashSkipListRep: The memtable rep that is best used for keys that are
-//  structured like "prefix:suffix" where iteration withing a prefix is
+//  structured like "prefix:suffix" where iteration within a prefix is
 //  common and iteration across different prefixes is rare. It is backed by
 //  a hash map where each bucket is a skip list.
 //  - VectorRep: This is backed by an unordered std::vector. On iteration, the
@@ -85,7 +85,7 @@ class MemTableRep {
     // Initialize an iterator over the specified collection.
     // The returned iterator is not valid.
     // explicit Iterator(const MemTableRep* collection);
-    virtual ~Iterator() { };
+    virtual ~Iterator() {}
 
     // Returns true iff the iterator is positioned at a valid node.
     virtual bool Valid() const = 0;
@@ -143,7 +143,7 @@ class MemTableRep {
 // new MemTableRep objects
 class MemTableRepFactory {
  public:
-  virtual ~MemTableRepFactory() { };
+  virtual ~MemTableRepFactory() {}
   virtual MemTableRep* CreateMemTableRep(MemTableRep::KeyComparator&,
                                          Arena*) = 0;
   virtual const char* Name() const = 0;
@@ -159,7 +159,8 @@ class MemTableRepFactory {
 //     bytes reserved for usage.
 class VectorRepFactory : public MemTableRepFactory {
   const size_t count_;
-public:
+
+ public:
   explicit VectorRepFactory(size_t count = 0) : count_(count) { }
   virtual MemTableRep* CreateMemTableRep(MemTableRep::KeyComparator&,
                                          Arena*) override;
@@ -170,9 +171,9 @@ public:
 
 // This uses a skip list to store keys. It is the default.
 class SkipListFactory : public MemTableRepFactory {
-public:
- virtual MemTableRep* CreateMemTableRep(MemTableRep::KeyComparator&,
-                                        Arena*) override;
+ public:
+  virtual MemTableRep* CreateMemTableRep(MemTableRep::KeyComparator&,
+                                         Arena*) override;
   virtual const char* Name() const override {
     return "SkipListFactory";
   }
@@ -196,4 +197,4 @@ extern MemTableRepFactory* NewHashSkipListRepFactory(
 extern MemTableRepFactory* NewHashLinkListRepFactory(
     const SliceTransform* transform, size_t bucket_count = 50000);
 
-}
+}  // namespace rocksdb

table/format.cc

@@ -9,6 +9,8 @@
 
 #include "table/format.h"
 
+#include <string>
+
 #include "port/port.h"
 #include "rocksdb/env.h"
 #include "table/block.h"
@@ -43,8 +45,8 @@ void Footer::EncodeTo(std::string* dst) const {
   metaindex_handle_.EncodeTo(dst);
   index_handle_.EncodeTo(dst);
   dst->resize(2 * BlockHandle::kMaxEncodedLength);  // Padding
-  PutFixed32(dst, static_cast<uint32_t>(kTableMagicNumber & 0xffffffffu));
-  PutFixed32(dst, static_cast<uint32_t>(kTableMagicNumber >> 32));
+  PutFixed32(dst, static_cast<uint32_t>(table_magic_number() & 0xffffffffu));
+  PutFixed32(dst, static_cast<uint32_t>(table_magic_number() >> 32));
   assert(dst->size() == original_size + kEncodedLength);
 }
 
@@ -52,13 +54,21 @@ Status Footer::DecodeFrom(Slice* input) {
   assert(input != nullptr);
   assert(input->size() >= kEncodedLength);
 
-  const char* magic_ptr = input->data() + kEncodedLength - 8;
+  const char* magic_ptr =
+      input->data() + kEncodedLength - kMagicNumberLengthByte;
   const uint32_t magic_lo = DecodeFixed32(magic_ptr);
   const uint32_t magic_hi = DecodeFixed32(magic_ptr + 4);
   const uint64_t magic = ((static_cast<uint64_t>(magic_hi) << 32) |
                           (static_cast<uint64_t>(magic_lo)));
-  if (magic != kTableMagicNumber) {
-    return Status::InvalidArgument("not an sstable (bad magic number)");
+  if (HasInitializedTableMagicNumber()) {
+    if (magic != table_magic_number()) {
+      char buffer[80];
+      snprintf(buffer, sizeof(buffer) - 1,
+               "not an sstable (bad magic number --- %lx)", magic);
+      return Status::InvalidArgument(buffer);
+    }
+  } else {
+    set_table_magic_number(magic);
   }
 
   Status result = metaindex_handle_.DecodeFrom(input);
@@ -221,7 +231,7 @@ Status UncompressBlockContents(const char* data, size_t n,
     default:
       return Status::Corruption("bad block type");
   }
-  result->compression_type = kNoCompression; // not compressed any more
+  result->compression_type = kNoCompression;  // not compressed any more
   return Status::OK();
 }
 

table/format.h

@@ -21,6 +21,9 @@ class Block;
 class RandomAccessFile;
 struct ReadOptions;
 
+// the length of the magic number in bytes.
+const int kMagicNumberLengthByte = 8;
+
 // BlockHandle is a pointer to the extent of a file that stores a data
 // block or a meta block.
 class BlockHandle {
@@ -63,12 +66,16 @@ class BlockHandle {
 // end of every table file.
 class Footer {
  public:
+  // Constructs a footer without specifying its table magic number.
+  // In such case, the table magic number of such footer should be
+  // initialized via @ReadFooterFromFile().
+  Footer() : Footer(kInvalidTableMagicNumber) {}
+
   // @table_magic_number serves two purposes:
   //  1. Identify different types of the tables.
   //  2. Help us to identify if a given file is a valid sst.
-  Footer(uint64_t table_magic_number) :
-      kTableMagicNumber(table_magic_number) {
-  }
+  explicit Footer(uint64_t table_magic_number)
+      : table_magic_number_(table_magic_number) {}
 
   // The block handle for the metaindex block of the table
   const BlockHandle& metaindex_handle() const { return metaindex_handle_; }
@@ -78,24 +85,52 @@ class Footer {
   const BlockHandle& index_handle() const {
     return index_handle_;
   }
+
   void set_index_handle(const BlockHandle& h) {
     index_handle_ = h;
   }
 
+  uint64_t table_magic_number() const { return table_magic_number_; }
+
   void EncodeTo(std::string* dst) const;
+
+  // Set the current footer based on the input slice.  If table_magic_number_
+  // is not set (i.e., HasInitializedTableMagicNumber() is true), then this
+  // function will also initialize table_magic_number_.  Otherwise, this
+  // function will verify whether the magic number specified in the input
+  // slice matches table_magic_number_ and update the current footer only
+  // when the test passes.
   Status DecodeFrom(Slice* input);
 
   // Encoded length of a Footer.  Note that the serialization of a
   // Footer will always occupy exactly this many bytes.  It consists
   // of two block handles and a magic number.
   enum {
-    kEncodedLength = 2*BlockHandle::kMaxEncodedLength + 8
+    kEncodedLength = 2 * BlockHandle::kMaxEncodedLength + 8
   };
 
+  const uint64_t kInvalidTableMagicNumber = 0;
+
  private:
+  // Set the table_magic_number only when it was not previously
+  // initialized.  Return true on success.
+  bool set_table_magic_number(uint64_t magic_number) {
+    if (HasInitializedTableMagicNumber()) {
+      table_magic_number_ = magic_number;
+      return true;
+    }
+    return false;
+  }
+
+  // return true if @table_magic_number_ is set to a value different
+  // from @kInvalidTableMagicNumber.
+  bool HasInitializedTableMagicNumber() const {
+    return (table_magic_number_ != kInvalidTableMagicNumber);
+  }
+
   BlockHandle metaindex_handle_;
   BlockHandle index_handle_;
-  const uint64_t kTableMagicNumber;
+  uint64_t table_magic_number_;
 };
 
 // Read the footer from file

table/meta_blocks.cc

@@ -2,12 +2,13 @@
 //  This source code is licensed under the BSD-style license found in the
 //  LICENSE file in the root directory of this source tree. An additional grant
 //  of patent rights can be found in the PATENTS file in the same directory.
-
 #include "table/meta_blocks.h"
 
 #include <map>
+#include <string>
 
 #include "rocksdb/table.h"
+#include "rocksdb/table_properties.h"
 #include "table/block.h"
 #include "table/format.h"
 #include "util/coding.h"
@@ -104,9 +105,8 @@ bool NotifyCollectTableCollectorsOnAdd(
     Status s = collector->Add(key, value);
     all_succeeded = all_succeeded && s.ok();
     if (!s.ok()) {
-      LogPropertiesCollectionError(
-          info_log, "Add", /* method */ collector->Name()
-      );
+      LogPropertiesCollectionError(info_log, "Add" /* method */,
+                                   collector->Name());
     }
   }
   return all_succeeded;
@@ -123,9 +123,8 @@ bool NotifyCollectTableCollectorsOnFinish(
 
     all_succeeded = all_succeeded && s.ok();
     if (!s.ok()) {
-      LogPropertiesCollectionError(
-          info_log, "Finish", /* method */ collector->Name()
-      );
+      LogPropertiesCollectionError(info_log, "Finish" /* method */,
+                                   collector->Name());
     } else {
       builder->Add(user_collected_properties);
     }
@@ -151,14 +150,8 @@ Status ReadProperties(
   BlockContents block_contents;
   ReadOptions read_options;
   read_options.verify_checksums = false;
-  Status s = ReadBlockContents(
-      file,
-      read_options,
-      handle,
-      &block_contents,
-      env,
-      false
-  );
+  Status s = ReadBlockContents(file, read_options, handle, &block_contents, env,
+                               false);
 
   if (!s.ok()) {
     return s;
@@ -166,22 +159,20 @@ Status ReadProperties(
 
   Block properties_block(block_contents);
   std::unique_ptr<Iterator> iter(
-      properties_block.NewIterator(BytewiseComparator())
-  );
+      properties_block.NewIterator(BytewiseComparator()));
 
   // All pre-defined properties of type uint64_t
   std::unordered_map<std::string, uint64_t*> predefined_uint64_properties = {
-    { TablePropertiesNames::kDataSize, &table_properties->data_size },
-    { TablePropertiesNames::kIndexSize, &table_properties->index_size },
-    { TablePropertiesNames::kFilterSize, &table_properties->filter_size },
-    { TablePropertiesNames::kRawKeySize, &table_properties->raw_key_size },
-    { TablePropertiesNames::kRawValueSize, &table_properties->raw_value_size },
-    { TablePropertiesNames::kNumDataBlocks,
-      &table_properties->num_data_blocks },
-    { TablePropertiesNames::kNumEntries, &table_properties->num_entries },
-    { TablePropertiesNames::kFormatVersion, &table_properties->format_version },
-    { TablePropertiesNames::kFixedKeyLen, &table_properties->fixed_key_len },
-  };
+      {TablePropertiesNames::kDataSize, &table_properties->data_size},
+      {TablePropertiesNames::kIndexSize, &table_properties->index_size},
+      {TablePropertiesNames::kFilterSize, &table_properties->filter_size},
+      {TablePropertiesNames::kRawKeySize, &table_properties->raw_key_size},
+      {TablePropertiesNames::kRawValueSize, &table_properties->raw_value_size},
+      {TablePropertiesNames::kNumDataBlocks,
+       &table_properties->num_data_blocks},
+      {TablePropertiesNames::kNumEntries, &table_properties->num_entries},
+      {TablePropertiesNames::kFormatVersion, &table_properties->format_version},
+      {TablePropertiesNames::kFixedKeyLen, &table_properties->fixed_key_len}};
 
   std::string last_key;
   for (iter->SeekToFirst(); iter->Valid(); iter->Next()) {
@@ -192,10 +183,8 @@ Status ReadProperties(
 
     auto key = iter->key().ToString();
     // properties block is strictly sorted with no duplicate key.
-    assert(
-        last_key.empty() ||
-        BytewiseComparator()->Compare(key, last_key) > 0
-    );
+    assert(last_key.empty() ||
+           BytewiseComparator()->Compare(key, last_key) > 0);
     last_key = key;
 
     auto raw_val = iter->value();
@@ -218,8 +207,7 @@ Status ReadProperties(
     } else {
       // handle user-collected properties
       table_properties->user_collected_properties.insert(
-          std::make_pair(key, raw_val.ToString())
-      );
+          {key, raw_val.ToString()});
     }
   }
 
@@ -244,21 +232,14 @@ Status ReadTableProperties(
   BlockContents metaindex_contents;
   ReadOptions read_options;
   read_options.verify_checksums = false;
-  s = ReadBlockContents(
-      file,
-      read_options,
-      metaindex_handle,
-      &metaindex_contents,
-      env,
-      false
-  );
+  s = ReadBlockContents(file, read_options, metaindex_handle,
+                        &metaindex_contents, env, false);
   if (!s.ok()) {
     return s;
   }
   Block metaindex_block(metaindex_contents);
   std::unique_ptr<Iterator> meta_iter(
-      metaindex_block.NewIterator(BytewiseComparator())
-  );
+      metaindex_block.NewIterator(BytewiseComparator()));
 
   // -- Read property block
   meta_iter->Seek(kPropertiesBlock);
@@ -266,21 +247,39 @@ Status ReadTableProperties(
   if (meta_iter->Valid() &&
       meta_iter->key() == kPropertiesBlock &&
       meta_iter->status().ok()) {
-    s = ReadProperties(
-        meta_iter->value(),
-        file,
-        env,
-        info_log,
-        properties
-    );
+    s = ReadProperties(meta_iter->value(), file, env, info_log, properties);
   } else {
     s = Status::Corruption(
-        "Unable to read the property block from the plain table"
-    );
+        "Unable to read the property block from the plain table");
   }
 
   return s;
 }
 
+Status ReadTableMagicNumber(const std::string& file_path,
+                            const Options& options,
+                            const EnvOptions& env_options,
+                            uint64_t* table_magic_number) {
+  unique_ptr<RandomAccessFile> file;
+  Status s = options.env->NewRandomAccessFile(file_path, &file, env_options);
+  if (!s.ok()) {
+    return s;
+  }
+
+  uint64_t file_size;
+  options.env->GetFileSize(file_path, &file_size);
+  if (file_size < Footer::kEncodedLength) {
+    return Status::InvalidArgument("file is too short to be an sstable");
+  }
+
+  Footer footer;
+  s = ReadFooterFromFile(file.get(), file_size, &footer);
+  if (!s.ok()) {
+    return s;
+  }
+
+  *table_magic_number = footer.table_magic_number();
+  return Status::OK();
+}
 
 }  // namespace rocksdb

table/meta_blocks.h

@@ -8,6 +8,7 @@
 #include <memory>
 #include <string>
 
+#include "db/builder.h"
 #include "rocksdb/comparator.h"
 #include "rocksdb/options.h"
 #include "rocksdb/slice.h"
@@ -118,4 +119,10 @@ Status ReadTableProperties(
     Logger* info_log,
     TableProperties* properties);
 
+// Read the magic number of the specified file directly.  The magic number
+// of a valid sst table the last 8-byte of the file.
+Status ReadTableMagicNumber(const std::string& file_path,
+                            const Options& options,
+                            const EnvOptions& env_options,
+                            uint64_t* table_magic_number);
 }  // namespace rocksdb

table/table_properties.cc

@@ -40,50 +40,31 @@ std::string TableProperties::ToString(
   result.reserve(1024);
 
   // Basic Info
-  AppendProperty(
-      result, "# data blocks", num_data_blocks, prop_delim, kv_delim
-  );
+  AppendProperty(result, "# data blocks", num_data_blocks, prop_delim,
+                 kv_delim);
   AppendProperty(result, "# entries", num_entries, prop_delim, kv_delim);
 
   AppendProperty(result, "raw key size", raw_key_size, prop_delim, kv_delim);
-  AppendProperty(
-      result,
-      "raw average key size",
-      num_entries != 0 ?  1.0 * raw_key_size / num_entries : 0.0,
-      prop_delim,
-      kv_delim
-  );
-  AppendProperty(
-      result, "raw value size", raw_value_size, prop_delim, kv_delim
-  );
-  AppendProperty(
-      result,
-      "raw average value size",
-      num_entries != 0 ?  1.0 * raw_value_size / num_entries : 0.0,
-      prop_delim,
-      kv_delim
-  );
+  AppendProperty(result, "raw average key size",
+                 num_entries != 0 ? 1.0 * raw_key_size / num_entries : 0.0,
+                 prop_delim, kv_delim);
+  AppendProperty(result, "raw value size", raw_value_size, prop_delim,
+                 kv_delim);
+  AppendProperty(result, "raw average value size",
+                 num_entries != 0 ? 1.0 * raw_value_size / num_entries : 0.0,
+                 prop_delim, kv_delim);
 
   AppendProperty(result, "data block size", data_size, prop_delim, kv_delim);
   AppendProperty(result, "index block size", index_size, prop_delim, kv_delim);
-  AppendProperty(
-      result, "filter block size", filter_size, prop_delim, kv_delim
-  );
-  AppendProperty(
-      result,
-      "(estimated) table size",
-      data_size + index_size + filter_size,
-      prop_delim,
-      kv_delim
-  );
+  AppendProperty(result, "filter block size", filter_size, prop_delim,
+                 kv_delim);
+  AppendProperty(result, "(estimated) table size",
+                 data_size + index_size + filter_size, prop_delim, kv_delim);
 
   AppendProperty(
-      result,
-      "filter policy name",
+      result, "filter policy name",
       filter_policy_name.empty() ? std::string("N/A") : filter_policy_name,
-      prop_delim,
-      kv_delim
-  );
+      prop_delim, kv_delim);
 
   return result;
 }

table/table_test.cc

@@ -6,6 +6,9 @@
 // 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 <inttypes.h>
+#include <stdio.h>
 #include <algorithm>
 #include <map>
 #include <string>
@@ -25,6 +28,7 @@
 #include "rocksdb/slice_transform.h"
 #include "rocksdb/memtablerep.h"
 #include "table/block.h"
+#include "table/meta_blocks.h"
 #include "table/block_based_table_builder.h"
 #include "table/block_based_table_factory.h"
 #include "table/block_based_table_reader.h"
@@ -945,10 +949,7 @@ TEST(BlockBasedTableTest, BasicBlockBasedTableProperties) {
     block_builder.Add(item.first, item.second);
   }
   Slice content = block_builder.Finish();
-  ASSERT_EQ(
-      content.size() + kBlockTrailerSize,
-      props.data_size
-  );
+  ASSERT_EQ(content.size() + kBlockTrailerSize, props.data_size);
 }
 
 TEST(BlockBasedTableTest, FilterPolicyNameProperties) {
@@ -957,9 +958,7 @@ TEST(BlockBasedTableTest, FilterPolicyNameProperties) {
   std::vector<std::string> keys;
   KVMap kvmap;
   Options options;
-  std::unique_ptr<const FilterPolicy> filter_policy(
-    NewBloomFilterPolicy(10)
-  );
+  std::unique_ptr<const FilterPolicy> filter_policy(NewBloomFilterPolicy(10));
   options.filter_policy = filter_policy.get();
 
   c.Finish(options, GetPlainInternalComparator(options.comparator), &keys,
@@ -1031,10 +1030,8 @@ TEST(BlockBasedTableTest, NumBlockStat) {
   KVMap kvmap;
   c.Finish(options, GetPlainInternalComparator(options.comparator), &ks,
            &kvmap);
-  ASSERT_EQ(
-      kvmap.size(),
-      c.table_reader()->GetTableProperties().num_data_blocks
-  );
+  ASSERT_EQ(kvmap.size(),
+            c.table_reader()->GetTableProperties().num_data_blocks);
 }
 
 class BlockCacheProperties {
@@ -1049,32 +1046,26 @@ class BlockCacheProperties {
   }
 
   // Check if the fetched props matches the expected ones.
-  void AssertEqual(
-      long index_block_cache_miss,
-      long index_block_cache_hit,
-      long data_block_cache_miss,
-      long data_block_cache_hit) const {
+  void AssertEqual(int64_t index_block_cache_miss,
+                   int64_t index_block_cache_hit, int64_t data_block_cache_miss,
+                   int64_t data_block_cache_hit) const {
     ASSERT_EQ(index_block_cache_miss, this->index_block_cache_miss);
     ASSERT_EQ(index_block_cache_hit, this->index_block_cache_hit);
     ASSERT_EQ(data_block_cache_miss, this->data_block_cache_miss);
     ASSERT_EQ(data_block_cache_hit, this->data_block_cache_hit);
-    ASSERT_EQ(
-        index_block_cache_miss + data_block_cache_miss,
-        this->block_cache_miss
-    );
-    ASSERT_EQ(
-        index_block_cache_hit + data_block_cache_hit,
-        this->block_cache_hit
-    );
+    ASSERT_EQ(index_block_cache_miss + data_block_cache_miss,
+              this->block_cache_miss);
+    ASSERT_EQ(index_block_cache_hit + data_block_cache_hit,
+              this->block_cache_hit);
   }
 
  private:
-  long block_cache_miss = 0;
-  long block_cache_hit = 0;
-  long index_block_cache_miss = 0;
-  long index_block_cache_hit = 0;
-  long data_block_cache_miss = 0;
-  long data_block_cache_hit = 0;
+  int64_t block_cache_miss = 0;
+  int64_t block_cache_hit = 0;
+  int64_t index_block_cache_miss = 0;
+  int64_t index_block_cache_hit = 0;
+  int64_t data_block_cache_miss = 0;
+  int64_t data_block_cache_hit = 0;
 };
 
 TEST(BlockBasedTableTest, BlockCacheTest) {
@@ -1104,12 +1095,8 @@ TEST(BlockBasedTableTest, BlockCacheTest) {
   {
     BlockCacheProperties props(options.statistics.get());
     // index will be added to block cache.
-    props.AssertEqual(
-        1,  // index block miss
-        0,
-        0,
-        0
-    );
+    props.AssertEqual(1,  // index block miss
+                      0, 0, 0);
   }
 
   // Only index block will be accessed
@@ -1119,24 +1106,16 @@ TEST(BlockBasedTableTest, BlockCacheTest) {
     // NOTE: to help better highlight the "detla" of each ticker, I use
     // <last_value> + <added_value> to indicate the increment of changed
     // value; other numbers remain the same.
-    props.AssertEqual(
-        1,
-        0 + 1,  // index block hit
-        0,
-        0
-    );
+    props.AssertEqual(1, 0 + 1,  // index block hit
+                      0, 0);
   }
 
   // Only data block will be accessed
   {
     iter->SeekToFirst();
     BlockCacheProperties props(options.statistics.get());
-    props.AssertEqual(
-        1,
-        1,
-        0 + 1,  // data block miss
-        0
-    );
+    props.AssertEqual(1, 1, 0 + 1,  // data block miss
+                      0);
   }
 
   // Data block will be in cache
@@ -1144,12 +1123,8 @@ TEST(BlockBasedTableTest, BlockCacheTest) {
     iter.reset(c.NewIterator());
     iter->SeekToFirst();
     BlockCacheProperties props(options.statistics.get());
-    props.AssertEqual(
-        1,
-        1 + 1,  // index block hit
-        1,
-        0 + 1  // data block hit
-    );
+    props.AssertEqual(1, 1 + 1, /* index block hit */
+                      1, 0 + 1 /* data block hit */);
   }
   // release the iterator so that the block cache can reset correctly.
   iter.reset();
@@ -1175,12 +1150,8 @@ TEST(BlockBasedTableTest, BlockCacheTest) {
   c.Reopen(options);
   {
     BlockCacheProperties props(options.statistics.get());
-    props.AssertEqual(
-        1,  // index block miss
-        0,
-        0,
-        0
-    );
+    props.AssertEqual(1,  // index block miss
+                      0, 0, 0);
   }
 
 
@@ -1190,12 +1161,9 @@ TEST(BlockBasedTableTest, BlockCacheTest) {
     // is only 1, index block will be purged after data block is inserted.
     iter.reset(c.NewIterator());
     BlockCacheProperties props(options.statistics.get());
-    props.AssertEqual(
-        1 + 1,  // index block miss
-        0,
-        0,  // data block miss
-        0
-    );
+    props.AssertEqual(1 + 1,  // index block miss
+                      0, 0,   // data block miss
+                      0);
   }
 
   {
@@ -1203,12 +1171,8 @@ TEST(BlockBasedTableTest, BlockCacheTest) {
     // block's cache miss.
     iter->SeekToFirst();
     BlockCacheProperties props(options.statistics.get());
-    props.AssertEqual(
-        2,
-        0,
-        0 + 1,  // data block miss
-        0
-    );
+    props.AssertEqual(2, 0, 0 + 1,  // data block miss
+                      0);
   }
 }
 
@@ -1315,7 +1279,6 @@ TEST(GeneralTableTest, ApproximateOffsetOfPlain) {
   ASSERT_TRUE(Between(c.ApproximateOffsetOf("k06"),  510000, 511000));
   ASSERT_TRUE(Between(c.ApproximateOffsetOf("k07"),  510000, 511000));
   ASSERT_TRUE(Between(c.ApproximateOffsetOf("xyz"),  610000, 612000));
-
 }
 
 static void DoCompressionTest(CompressionType comp) {
@@ -1359,11 +1322,9 @@ TEST(GeneralTableTest, ApproximateOffsetOfCompressed) {
     valid++;
   }
 
-  for(int i =0; i < valid; i++)
-  {
+  for (int i = 0; i < valid; i++) {
     DoCompressionTest(compression_state[i]);
   }
-
 }
 
 TEST(Harness, Randomized) {
@@ -1374,8 +1335,8 @@ TEST(Harness, Randomized) {
     for (int num_entries = 0; num_entries < 2000;
          num_entries += (num_entries < 50 ? 1 : 200)) {
       if ((num_entries % 10) == 0) {
-        fprintf(stderr, "case %d of %d: num_entries = %d\n",
-                (i + 1), int(args.size()), num_entries);
+        fprintf(stderr, "case %d of %d: num_entries = %d\n", (i + 1),
+                static_cast<int>(args.size()), num_entries);
       }
       for (int e = 0; e < num_entries; e++) {
         std::string v;

tools/sst_dump.cc

@@ -14,10 +14,14 @@
 #include "rocksdb/db.h"
 #include "rocksdb/env.h"
 #include "rocksdb/iterator.h"
+#include "rocksdb/slice_transform.h"
 #include "rocksdb/table.h"
 #include "rocksdb/table_properties.h"
+#include "table/block_based_table_factory.h"
+#include "table/plain_table_factory.h"
 #include "table/block.h"
 #include "table/block_builder.h"
+#include "table/meta_blocks.h"
 #include "table/format.h"
 #include "util/ldb_cmd.h"
 #include "util/random.h"
@@ -44,6 +48,9 @@ class SstFileReader {
 
  private:
   Status NewTableReader(const std::string& file_path);
+  Status SetTableOptionsByMagicNumber(uint64_t table_magic_number,
+                                      RandomAccessFile* file,
+                                      uint64_t file_size);
 
   std::string file_name_;
   uint64_t read_num_;
@@ -54,9 +61,9 @@ class SstFileReader {
   Status init_result_;
   unique_ptr<TableReader> table_reader_;
   unique_ptr<RandomAccessFile> file_;
-  // table_options_ and internal_comparator_ will also be used in
+  // options_ and internal_comparator_ will also be used in
   // ReadSequential internally (specifically, seek-related operations)
-  Options table_options_;
+  Options options_;
   InternalKeyComparator internal_comparator_;
 };
 
@@ -70,21 +77,68 @@ SstFileReader::SstFileReader(const std::string& file_path,
   init_result_ = NewTableReader(file_name_);
 }
 
+extern uint64_t kBlockBasedTableMagicNumber;
+extern uint64_t kPlainTableMagicNumber;
+
 Status SstFileReader::NewTableReader(const std::string& file_path) {
-  Status s = table_options_.env->NewRandomAccessFile(file_path, &file_,
-                                                    soptions_);
+  uint64_t magic_number;
+  Status s =
+      ReadTableMagicNumber(file_path, options_, soptions_, &magic_number);
+  if (!s.ok()) {
+    return s;
+  }
+  if (magic_number == kPlainTableMagicNumber) {
+    soptions_.use_mmap_reads = true;
+  }
+  options_.comparator = &internal_comparator_;
+
+  s = options_.env->NewRandomAccessFile(file_path, &file_, soptions_);
   if (!s.ok()) {
     return s;
   }
   uint64_t file_size;
-  table_options_.env->GetFileSize(file_path, &file_size);
-  unique_ptr<TableFactory> table_factory;
-  s = table_options_.table_factory->NewTableReader(
-      table_options_, soptions_, internal_comparator_, std::move(file_),
-      file_size, &table_reader_);
+  options_.env->GetFileSize(file_path, &file_size);
+  s = SetTableOptionsByMagicNumber(magic_number, file_.get(), file_size);
+  if (!s.ok()) {
+    return s;
+  }
+
+  s = options_.table_factory->NewTableReader(
+      options_, soptions_, internal_comparator_, std::move(file_), file_size,
+      &table_reader_);
   return s;
 }
 
+Status SstFileReader::SetTableOptionsByMagicNumber(uint64_t table_magic_number,
+                                                   RandomAccessFile* file,
+                                                   uint64_t file_size) {
+  TableProperties table_properties;
+  Status s = rocksdb::ReadTableProperties(file, file_size, table_magic_number,
+                                          options_.env, options_.info_log.get(),
+                                          &table_properties);
+  if (!s.ok()) {
+    return s;
+  }
+
+  if (table_magic_number == kBlockBasedTableMagicNumber) {
+    options_.table_factory = std::make_shared<BlockBasedTableFactory>();
+    fprintf(stdout, "Sst file format: block-based\n");
+  } else if (table_magic_number == kPlainTableMagicNumber) {
+    options_.allow_mmap_reads = true;
+    options_.table_factory = std::make_shared<PlainTableFactory>(
+        table_properties.fixed_key_len, 2, 0.8);
+    options_.prefix_extractor = NewNoopTransform();
+    fprintf(stdout, "Sst file format: plain table\n");
+  } else {
+    char error_msg_buffer[80];
+    snprintf(error_msg_buffer, sizeof(error_msg_buffer) - 1,
+             "Unsupported table magic number --- %lx)", table_magic_number);
+    return Status::InvalidArgument(error_msg_buffer);
+  }
+
+  return Status::OK();
+}
+
 Status SstFileReader::ReadSequential(bool print_kv,
                                      uint64_t read_num,
                                      bool has_from,