Add rocksdb_livefiles_column_family_name C API (#9232)

Summary:
Extend C API to add new function `rocksdb_livefiles_column_family_name`.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/9232

Reviewed By: akankshamahajan15

Differential Revision: D32736516

Pulled By: ajkr

fbshipit-source-id: a854256a0f4652c903ab5ad8355ded051ac19987

db/c.cc

@@ -4737,6 +4737,11 @@ int rocksdb_livefiles_count(
   return static_cast<int>(lf->rep.size());
 }
 
+const char* rocksdb_livefiles_column_family_name(const rocksdb_livefiles_t* lf,
+                                                 int index) {
+  return lf->rep[index].column_family_name.c_str();
+}
+
 const char* rocksdb_livefiles_name(
   const rocksdb_livefiles_t* lf,
   int index) {

include/rocksdb/c.h

@@ -1995,6 +1995,8 @@ extern ROCKSDB_LIBRARY_API void rocksdb_fifo_compaction_options_destroy(
 
 extern ROCKSDB_LIBRARY_API int rocksdb_livefiles_count(
     const rocksdb_livefiles_t*);
+extern ROCKSDB_LIBRARY_API const char* rocksdb_livefiles_column_family_name(
+    const rocksdb_livefiles_t*, int index);
 extern ROCKSDB_LIBRARY_API const char* rocksdb_livefiles_name(
     const rocksdb_livefiles_t*, int index);
 extern ROCKSDB_LIBRARY_API int rocksdb_livefiles_level(