From e2b1f47bc5a132476e77429f6098a83e3ae83ec6 Mon Sep 17 00:00:00 2001
From: Anay Wadhera <awadhera@google.com>
Date: Thu, 27 Feb 2025 10:33:44 -0800
Subject: [PATCH] Add a function to free the memory allocated when calling
 GetStringFlag

PiperOrigin-RevId: 731778685
---
 connections/c/nc.cc      | 4 +++-
 connections/c/nc_types.h | 2 ++
 2 files changed, 5 insertions(+), 1 deletion(-)

diff --git a/connections/c/nc.cc b/connections/c/nc.cc
index e94c0442..4ef62a63 100644
--- a/connections/c/nc.cc
+++ b/connections/c/nc.cc
@@ -103,7 +103,9 @@ class FlagReaderWrapper : public nearby::flags::FlagReader {
     };
     NC_DATA flag_value = phenotype_flag_reader_.get_string_flag_value(
         context_, &flag_name, &default_value);
-    return std::string(flag_value.data, flag_value.size);
+    std::string ret = std::string(flag_value.data, flag_value.size);
+    phenotype_flag_reader_.free_string_value(&flag_value);
+    return ret;
   }
 
  private:
diff --git a/connections/c/nc_types.h b/connections/c/nc_types.h
index d173ef2b..50a3cc09 100644
--- a/connections/c/nc_types.h
+++ b/connections/c/nc_types.h
@@ -337,6 +337,8 @@ typedef struct NC_PHENOTYPE_FLAG_READER {
   const NC_DATA (*get_string_flag_value)(READER_CONTEXT context,
                                          const NC_DATA* flag_name,
                                          const NC_DATA* default_value);
+  // Frees a string allocated when calling get_string_flag_value.
+  const void (*free_string_value)(const NC_DATA* value);
 } NC_PHENOTYPE_FLAG_READER;
 
 #ifdef __cplusplus