Block ReadOnlyDB in ROCKSDB_LITE

Summary:
db_imp_readonly.o is one of the big obj file.  If it's not a necessary
feature, we should probably block it in ROCKSDB_LITE.

    1322704 Nov 24 16:55 db/db_impl_readonly.o

Test Plan:
make shared_lib -j32
make ROCKSDB_LITE shared_lib -j32

Reviewers: ljin, igor

Reviewed By: igor

Subscribers: dhruba, leveldb

Differential Revision: https://reviews.facebook.net/D29583

db/db_impl_readonly.cc

@@ -3,6 +3,7 @@
 //  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 "db/db_impl_readonly.h"
 #include "utilities/compacted_db/compacted_db_impl.h"
 #include "db/db_impl.h"
@@ -13,6 +14,8 @@
 
 namespace rocksdb {
 
+#ifndef ROCKSDB_LITE
+
 DBImplReadOnly::DBImplReadOnly(const DBOptions& db_options,
                                const std::string& dbname)
     : DBImpl(db_options, dbname) {
@@ -97,12 +100,10 @@ Status DB::OpenForReadOnly(const Options& options, const std::string& dbname,
 
   // Try to first open DB as fully compacted DB
   Status s;
-#ifndef ROCKSDB_LITE
   s = CompactedDBImpl::Open(options, dbname, dbptr);
   if (s.ok()) {
     return s;
   }
-#endif
 
   DBOptions db_options(options);
   ColumnFamilyOptions cf_options(options);
@@ -167,5 +168,20 @@ Status DB::OpenForReadOnly(
   return s;
 }
 
+#else  // !ROCKSDB_LITE
+
+Status DB::OpenForReadOnly(const Options& options, const std::string& dbname,
+                           DB** dbptr, bool error_if_log_file_exist) {
+  return Status::NotSupported("Not supported in ROCKSDB_LITE.");
+}
+
+Status DB::OpenForReadOnly(
+    const DBOptions& db_options, const std::string& dbname,
+    const std::vector<ColumnFamilyDescriptor>& column_families,
+    std::vector<ColumnFamilyHandle*>* handles, DB** dbptr,
+    bool error_if_log_file_exist) {
+  return Status::NotSupported("Not supported in ROCKSDB_LITE.");
+}
+#endif  // !ROCKSDB_LITE
 
 }   // namespace rocksdb

db/db_impl_readonly.h

@@ -4,6 +4,9 @@
 //  of patent rights can be found in the PATENTS file in the same directory.
 
 #pragma once
+
+#ifndef ROCKSDB_LITE
+
 #include "db/db_impl.h"
 #include <vector>
 #include <string>
@@ -100,3 +103,5 @@ class DBImplReadOnly : public DBImpl {
   void operator=(const DBImplReadOnly&);
 };
 }
+
+#endif  // !ROCKSDB_LITE

include/rocksdb/db.h

@@ -101,6 +101,9 @@ class DB {
   // that modify data, like put/delete, will return error.
   // If the db is opened in read only mode, then no compactions
   // will happen.
+  //
+  // Not supported in ROCKSDB_LITE, in which case the function will
+  // return Status::NotSupported.
   static Status OpenForReadOnly(const Options& options,
       const std::string& name, DB** dbptr,
       bool error_if_log_file_exist = false);
@@ -110,6 +113,9 @@ class DB {
   // database that should be opened. However, you always need to specify default
   // column family. The default column family name is 'default' and it's stored
   // in rocksdb::kDefaultColumnFamilyName
+  //
+  // Not supported in ROCKSDB_LITE, in which case the function will
+  // return Status::NotSupported.
   static Status OpenForReadOnly(
       const DBOptions& db_options, const std::string& name,
       const std::vector<ColumnFamilyDescriptor>& column_families,