Replace namespace name "rocksdb" with ROCKSDB_NAMESPACE (#6433)

Summary:
When dynamically linking two binaries together, different builds of RocksDB from two sources might cause errors. To provide a tool for user to solve the problem, the RocksDB namespace is changed to a flag which can be overridden in build time.
Pull Request resolved: https://github.com/facebook/rocksdb/pull/6433

Test Plan: Build release, all and jtest. Try to build with ROCKSDB_NAMESPACE with another flag.

Differential Revision: D19977691

fbshipit-source-id: aa7f2d0972e1c31d75339ac48478f34f6cfcfb3e

8 files changed, 36 insertions, 35 deletions

diff --git a/examples/column_families_example.cc b/examples/column_families_example.cc
index 589ff8ec2..df936d46a 100644
--- a/examples/column_families_example.cc
+++ b/examples/column_families_example.cc
@@ -10,7 +10,7 @@
 #include "rocksdb/slice.h"
 #include "rocksdb/options.h"
 
-using namespace rocksdb;
+using namespace ROCKSDB_NAMESPACE;
 
 std::string kDBPath = "/tmp/rocksdb_column_families_example";
 
diff --git a/examples/compact_files_example.cc b/examples/compact_files_example.cc
index c27df8ee7..a0a9fa90a 100644
--- a/examples/compact_files_example.cc
+++ b/examples/compact_files_example.cc
@@ -12,7 +12,7 @@
 #include "rocksdb/env.h"
 #include "rocksdb/options.h"
 
-using namespace rocksdb;
+using namespace ROCKSDB_NAMESPACE;
 std::string kDBPath = "/tmp/rocksdb_compact_files_example";
 struct CompactionTask;
 
diff --git a/examples/compaction_filter_example.cc b/examples/compaction_filter_example.cc
index 226dfe790..cee763195 100644
--- a/examples/compaction_filter_example.cc
+++ b/examples/compaction_filter_example.cc
@@ -8,7 +8,7 @@
 #include <rocksdb/merge_operator.h>
 #include <rocksdb/options.h>
 
-class MyMerge : public rocksdb::MergeOperator {
+class MyMerge : public ROCKSDB_NAMESPACE::MergeOperator {
  public:
   virtual bool FullMergeV2(const MergeOperationInput& merge_in,
                            MergeOperationOutput* merge_out) const override {
@@ -17,7 +17,7 @@ class MyMerge : public rocksdb::MergeOperator {
       merge_out->new_value.assign(merge_in.existing_value->data(),
                                   merge_in.existing_value->size());
     }
-    for (const rocksdb::Slice& m : merge_in.operand_list) {
+    for (const ROCKSDB_NAMESPACE::Slice& m : merge_in.operand_list) {
       fprintf(stderr, "Merge(%s)\n", m.ToString().c_str());
       // the compaction filter filters out bad values
       assert(m.ToString() != "bad");
@@ -29,19 +29,20 @@ class MyMerge : public rocksdb::MergeOperator {
   const char* Name() const override { return "MyMerge"; }
 };
 
-class MyFilter : public rocksdb::CompactionFilter {
+class MyFilter : public ROCKSDB_NAMESPACE::CompactionFilter {
  public:
-  bool Filter(int level, const rocksdb::Slice& key,
-              const rocksdb::Slice& existing_value, std::string* new_value,
-              bool* value_changed) const override {
+  bool Filter(int level, const ROCKSDB_NAMESPACE::Slice& key,
+              const ROCKSDB_NAMESPACE::Slice& existing_value,
+              std::string* new_value, bool* value_changed) const override {
     fprintf(stderr, "Filter(%s)\n", key.ToString().c_str());
     ++count_;
     assert(*value_changed == false);
     return false;
   }
 
-  bool FilterMergeOperand(int level, const rocksdb::Slice& key,
-                          const rocksdb::Slice& existing_value) const override {
+  bool FilterMergeOperand(
+      int level, const ROCKSDB_NAMESPACE::Slice& key,
+      const ROCKSDB_NAMESPACE::Slice& existing_value) const override {
     fprintf(stderr, "FilterMerge(%s)\n", key.ToString().c_str());
     ++merge_count_;
     return existing_value == "bad";
@@ -54,8 +55,8 @@ class MyFilter : public rocksdb::CompactionFilter {
 };
 
 int main() {
-  rocksdb::DB* raw_db;
-  rocksdb::Status status;
+  ROCKSDB_NAMESPACE::DB* raw_db;
+  ROCKSDB_NAMESPACE::Status status;
 
   MyFilter filter;
 
@@ -64,22 +65,22 @@ int main() {
     fprintf(stderr, "Error deleting /tmp/rocksmergetest, code: %d\n", ret);
     return ret;
   }
-  rocksdb::Options options;
+  ROCKSDB_NAMESPACE::Options options;
   options.create_if_missing = true;
   options.merge_operator.reset(new MyMerge);
   options.compaction_filter = &filter;
-  status = rocksdb::DB::Open(options, "/tmp/rocksmergetest", &raw_db);
+  status = ROCKSDB_NAMESPACE::DB::Open(options, "/tmp/rocksmergetest", &raw_db);
   assert(status.ok());
-  std::unique_ptr<rocksdb::DB> db(raw_db);
+  std::unique_ptr<ROCKSDB_NAMESPACE::DB> db(raw_db);
 
-  rocksdb::WriteOptions wopts;
+  ROCKSDB_NAMESPACE::WriteOptions wopts;
   db->Merge(wopts, "0", "bad");  // This is filtered out
   db->Merge(wopts, "1", "data1");
   db->Merge(wopts, "1", "bad");
   db->Merge(wopts, "1", "data2");
   db->Merge(wopts, "1", "bad");
   db->Merge(wopts, "3", "data3");
-  db->CompactRange(rocksdb::CompactRangeOptions(), nullptr, nullptr);
+  db->CompactRange(ROCKSDB_NAMESPACE::CompactRangeOptions(), nullptr, nullptr);
   fprintf(stderr, "filter.count_ = %d\n", filter.count_);
   assert(filter.count_ == 0);
   fprintf(stderr, "filter.merge_count_ = %d\n", filter.merge_count_);
diff --git a/examples/multi_processes_example.cc b/examples/multi_processes_example.cc
index 921041a57..3241e36ea 100644
--- a/examples/multi_processes_example.cc
+++ b/examples/multi_processes_example.cc
@@ -36,17 +36,17 @@
 #include "rocksdb/options.h"
 #include "rocksdb/slice.h"
 
-using rocksdb::ColumnFamilyDescriptor;
-using rocksdb::ColumnFamilyHandle;
-using rocksdb::ColumnFamilyOptions;
-using rocksdb::DB;
-using rocksdb::FlushOptions;
-using rocksdb::Iterator;
-using rocksdb::Options;
-using rocksdb::ReadOptions;
-using rocksdb::Slice;
-using rocksdb::Status;
-using rocksdb::WriteOptions;
+using ROCKSDB_NAMESPACE::ColumnFamilyDescriptor;
+using ROCKSDB_NAMESPACE::ColumnFamilyHandle;
+using ROCKSDB_NAMESPACE::ColumnFamilyOptions;
+using ROCKSDB_NAMESPACE::DB;
+using ROCKSDB_NAMESPACE::FlushOptions;
+using ROCKSDB_NAMESPACE::Iterator;
+using ROCKSDB_NAMESPACE::Options;
+using ROCKSDB_NAMESPACE::ReadOptions;
+using ROCKSDB_NAMESPACE::Slice;
+using ROCKSDB_NAMESPACE::Status;
+using ROCKSDB_NAMESPACE::WriteOptions;
 
 const std::string kDBPath = "/tmp/rocksdb_multi_processes_example";
 const std::string kPrimaryStatusFile =
@@ -57,7 +57,7 @@ const size_t kNumKeysPerFlush = 1000;
 
 const std::vector<std::string>& GetColumnFamilyNames() {
   static std::vector<std::string> column_family_names = {
-      rocksdb::kDefaultColumnFamilyName, "pikachu"};
+      ROCKSDB_NAMESPACE::kDefaultColumnFamilyName, "pikachu"};
   return column_family_names;
 }
 
@@ -142,7 +142,7 @@ static bool ShouldCloseDB() { return true; }
 void CreateDB() {
   long my_pid = static_cast<long>(getpid());
   Options options;
-  Status s = rocksdb::DestroyDB(kDBPath, options);
+  Status s = ROCKSDB_NAMESPACE::DestroyDB(kDBPath, options);
   if (!s.ok()) {
     fprintf(stderr, "[process %ld] Failed to destroy DB: %s\n", my_pid,
             s.ToString().c_str());
@@ -159,7 +159,7 @@ void CreateDB() {
   std::vector<ColumnFamilyHandle*> handles;
   ColumnFamilyOptions cf_opts(options);
   for (const auto& cf_name : GetColumnFamilyNames()) {
-    if (rocksdb::kDefaultColumnFamilyName != cf_name) {
+    if (ROCKSDB_NAMESPACE::kDefaultColumnFamilyName != cf_name) {
       ColumnFamilyHandle* handle = nullptr;
       s = db->CreateColumnFamily(cf_opts, cf_name, &handle);
       if (!s.ok()) {
diff --git a/examples/optimistic_transaction_example.cc b/examples/optimistic_transaction_example.cc
index fda50d6ab..fd6dbad63 100644
--- a/examples/optimistic_transaction_example.cc
+++ b/examples/optimistic_transaction_example.cc
@@ -11,7 +11,7 @@
 #include "rocksdb/utilities/transaction.h"
 #include "rocksdb/utilities/optimistic_transaction_db.h"
 
-using namespace rocksdb;
+using namespace ROCKSDB_NAMESPACE;
 
 std::string kDBPath = "/tmp/rocksdb_transaction_example";
 
diff --git a/examples/options_file_example.cc b/examples/options_file_example.cc
index 5dd0a479c..e6a1d0e9a 100644
--- a/examples/options_file_example.cc
+++ b/examples/options_file_example.cc
@@ -18,7 +18,7 @@
 #include "rocksdb/table.h"
 #include "rocksdb/utilities/options_util.h"
 
-using namespace rocksdb;
+using namespace ROCKSDB_NAMESPACE;
 
 std::string kDBPath = "/tmp/rocksdb_options_file_example";
 
diff --git a/examples/simple_example.cc b/examples/simple_example.cc
index a8f80f091..256c965d7 100644
--- a/examples/simple_example.cc
+++ b/examples/simple_example.cc
@@ -10,7 +10,7 @@
 #include "rocksdb/slice.h"
 #include "rocksdb/options.h"
 
-using namespace rocksdb;
+using namespace ROCKSDB_NAMESPACE;
 
 std::string kDBPath = "/tmp/rocksdb_simple_example";
 
diff --git a/examples/transaction_example.cc b/examples/transaction_example.cc
index 54a4709c5..41b233544 100644
--- a/examples/transaction_example.cc
+++ b/examples/transaction_example.cc
@@ -11,7 +11,7 @@
 #include "rocksdb/utilities/transaction.h"
 #include "rocksdb/utilities/transaction_db.h"
 
-using namespace rocksdb;
+using namespace ROCKSDB_NAMESPACE;
 
 std::string kDBPath = "/tmp/rocksdb_transaction_example";