From 80b53d72446a06cdd2c90206ff7118cc44b5b6e0 Mon Sep 17 00:00:00 2001
From: Thejas-bhat <thejas.orkombu@couchbase.com>
Date: Thu, 1 Feb 2024 17:26:46 +0530
Subject: [PATCH] size API for c to get the size of index

---
 c_api/Index_c_ex.cpp | 8 +++++++-
 c_api/Index_c_ex.h   | 4 ++++
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/c_api/Index_c_ex.cpp b/c_api/Index_c_ex.cpp
index 569ca3236e..35ab5c97fa 100644
--- a/c_api/Index_c_ex.cpp
+++ b/c_api/Index_c_ex.cpp
@@ -8,7 +8,7 @@
 // Copyright 2023-present Facebook. All Rights Reserved.
 // -*- c++ -*-
 
-#include "Index_c.h"
+#include "Index_c_ex.h"
 #include <faiss/Index.h>
 #include "macros_impl.h"
 
@@ -30,4 +30,10 @@ int faiss_Index_merge_from(FaissIndex* index, FaissIndex* other, const idx_t add
     CATCH_AND_HANDLE
 }
 
+size_t faiss_Index_size(FaissIndex* index) {
+    auto xIndex = reinterpret_cast<faiss::Index*>(index);
+    size_t rv = sizeof(xIndex);
+    return rv;
+}
+
 }
\ No newline at end of file
diff --git a/c_api/Index_c_ex.h b/c_api/Index_c_ex.h
index 10812c1a62..10db00e304 100644
--- a/c_api/Index_c_ex.h
+++ b/c_api/Index_c_ex.h
@@ -12,9 +12,11 @@
 #define FAISS_INDEX_EX_C_H
 
 #include <stddef.h>
+#include <stdio.h>
 #include "faiss_c.h"
 #include "Index_c.h"
 
+
 #ifdef __cplusplus
 extern "C" {
 #endif
@@ -25,6 +27,8 @@ int faiss_Index_reconstruct_batch(const FaissIndex* index, idx_t n,
 
 int faiss_Index_merge_from(FaissIndex* index, FaissIndex* other, idx_t add_id);
 
+size_t faiss_Index_size(FaissIndex* index);
+
 #ifdef __cplusplus
 }
 #endif