From 6a3bd6a45f9ab1b6c915b5fdef5290ac8f3648d5 Mon Sep 17 00:00:00 2001
From: JeHee Yu <sees1234558@gmail.com>
Date: Wed, 14 May 2025 00:06:47 +0900
Subject: [PATCH] core: fix crash when payload pack_id is not numeric (#440)

---
 src/internal/sio_packet.cpp | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/internal/sio_packet.cpp b/src/internal/sio_packet.cpp
index 4b81098..6f6317a 100644
--- a/src/internal/sio_packet.cpp
+++ b/src/internal/sio_packet.cpp
@@ -321,7 +321,14 @@ namespace sio
 
         if(pos<json_pos)//we've got pack id.
         {
-            _pack_id = std::stoi(payload_ptr.substr(pos,json_pos - pos));
+	    std::string pack_id_str = payload_ptr.substr(pos, json_pos - pos);
+
+            if (std::all_of(pack_id_str.begin(), pack_id_str.end(), ::isdigit)) {
+                _pack_id = std::stoi(pack_id_str);
+            } 
+            else {
+                _pack_id = -1;
+            }
         }
         if (_frame == frame_message && (_type == type_binary_event || _type == type_binary_ack)) {
             //parse later when all buffers are arrived.