From cb69ff47f665a8fe90d07f3ece123a0161f088f4 Mon Sep 17 00:00:00 2001
From: Priyanka Kore <piyukore06@gmail.com>
Date: Sun, 1 Dec 2019 14:35:18 +0100
Subject: [PATCH] src: improve node_crypto.cc memory allocation

This avoids heap allocations in common cases

PR-URL: https://github.com/nodejs/node/pull/30751
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: David Carlier <devnexen@gmail.com>
Reviewed-By: Denys Otrishko <shishugi@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
---
 src/node_crypto.cc | 7 +++----
 1 file changed, 3 insertions(+), 4 deletions(-)

diff --git a/src/node_crypto.cc b/src/node_crypto.cc
index d1bd5471f3fba2..2d965bcbff5ea0 100644
--- a/src/node_crypto.cc
+++ b/src/node_crypto.cc
@@ -2697,11 +2697,11 @@ void SSLWrap<Base>::GetSharedSigalgs(const FunctionCallbackInfo<Value>& args) {
   Base* w;
   ASSIGN_OR_RETURN_UNWRAP(&w, args.Holder());
   Environment* env = w->ssl_env();
-  std::vector<Local<Value>> ret_arr;
 
   SSL* ssl = w->ssl_.get();
   int nsig = SSL_get_shared_sigalgs(ssl, 0, nullptr, nullptr, nullptr, nullptr,
                                     nullptr);
+  MaybeStackBuffer<Local<Value>, 16> ret_arr(nsig);
 
   for (int i = 0; i < nsig; i++) {
     int hash_nid;
@@ -2765,12 +2765,11 @@ void SSLWrap<Base>::GetSharedSigalgs(const FunctionCallbackInfo<Value>& args) {
     } else {
       sig_with_md += "UNDEF";
     }
-
-    ret_arr.push_back(OneByteString(env->isolate(), sig_with_md.c_str()));
+    ret_arr[i] = OneByteString(env->isolate(), sig_with_md.c_str());
   }
 
   args.GetReturnValue().Set(
-                 Array::New(env->isolate(), ret_arr.data(), ret_arr.size()));
+                 Array::New(env->isolate(), ret_arr.out(), ret_arr.length()));
 }