From 9e657323838d48127dfb949b0d24178df6ffdf0f Mon Sep 17 00:00:00 2001
From: polistern <polistern@i2pmail.org>
Date: Wed, 19 Jan 2022 04:37:20 +0000
Subject: [PATCH] fix: Rewrite createSAMRequest function with template.

---
 i2psam.cpp | 48 +-----------------------------------------------
 i2psam.h   | 46 +++++++++++++++++++++++++++++++++++++++++++++-
 2 files changed, 46 insertions(+), 48 deletions(-)

diff --git a/i2psam.cpp b/i2psam.cpp
index d2e1b17..588a6bc 100644
--- a/i2psam.cpp
+++ b/i2psam.cpp
@@ -9,8 +9,6 @@
  */
 
 #include <iostream>
-#include <cstdarg>
-#include <cstdio>
 #include <cstdlib>
 #include <cstring>
 #include <ctime>
@@ -29,16 +27,6 @@
 
 namespace SAM {
 
-static void print_error(const std::string &err) {
-#ifdef DEBUG_ON_STDOUT
-#ifdef WIN32
-  std::cout << err << "(" << WSAGetLastError() << ")" << std::endl;
-#else
-  std::cout << err << "(" << errno << ")" << std::endl;
-#endif
-#endif // DEBUG_ON_STDOUT
-}
-
 #ifdef WIN32
 int I2pSocket::instances_ = 0;
 
@@ -1047,41 +1035,7 @@ const std::string &RawSession::getSAMMinVer() const { return socket_.minVer_; }
 
 const std::string &RawSession::getSAMMaxVer() const { return socket_.maxVer_; }
 
-//--------------------------------------------------------------------------------------------------
-
-std::string Message::createSAMRequest(const char *format, ...) {
-  // ToDo: GR note: Creating a 65K byte buffer on the stack, and then wasting the time to zero it out
-  //                before using it.  Just to send a 30 byte string?, seems really wasteful to me, time more than storage, many mSec...
-
-  std::va_list args;
-  va_start(args, format);
-
-  std::va_list argsCopy;
-  va_copy(argsCopy, args);
-  const char * const formatCopy = format;
-  const int bufferStatus = std::vsnprintf(nullptr, 0, formatCopy, argsCopy);
-  va_end(argsCopy);
-
-  if (bufferStatus < 0) {
-    print_error("Failed to allocate buffer");
-    return {};
-  }
-
-  std::vector<char> buffer(bufferStatus + 1);
-  const int status = std::vsnprintf(buffer.data(), buffer.size(), formatCopy, args);
-  va_end(args);
-
-  if (status < 0) {
-    print_error("Failed to format message");
-    return {};
-  }
-
-#ifdef DEBUG_ON_STDOUT
-  std::cout << "Status: " << status << std::endl;
-#endif // DEBUG_ON_STDOUT
-
-  return {buffer.data()};
-}
+//-----------------------------------------------------------------------------
 
 std::string Message::hello(const std::string &minVer, const std::string &maxVer) {
   /**
diff --git a/i2psam.h b/i2psam.h
index 138fa7f..8d3b307 100644
--- a/i2psam.h
+++ b/i2psam.h
@@ -56,6 +56,8 @@
 
 //#ifdef __cplusplus
 
+//#include <cstdarg>
+#include <stdio.h>
 #include <cstdint>
 #include <list>
 #include <memory>
@@ -70,6 +72,16 @@ namespace SAM {
 
 typedef u_int SOCKET;
 
+static void print_error(const std::string &err) {
+#ifdef DEBUG_ON_STDOUT
+#ifdef WIN32
+  std::cout << err << "(" << WSAGetLastError() << ")" << std::endl;
+#else
+  std::cout << err << "(" << errno << ")" << std::endl;
+#endif
+#endif // DEBUG_ON_STDOUT
+}
+
 class Message {
  public:
   enum SessionStyle { sssStream, sssDatagram, sssRaw };
@@ -240,7 +252,39 @@ class Message {
                               const std::string &key);
 
  private:
-  static std::string createSAMRequest(const char *format, ...);
+  template<typename... t_args>
+  static std::string
+  createSAMRequest(const char *msg) { return {msg}; }
+
+  template<typename... t_args>
+  static std::string
+  createSAMRequest(const char *format, t_args &&... args)
+  {
+    // ToDo: Check allocated buffer size
+
+    const int bufferStatus = std::snprintf(nullptr, 0, format, args...);
+    if (bufferStatus < 0)
+      {
+        print_error("Failed to allocate buffer");
+        return {};
+      }
+
+    std::vector<char> buffer(bufferStatus + 1);
+    const int status =
+      std::snprintf(buffer.data(), buffer.size(), format, args...);
+
+    if (status < 0)
+      {
+        print_error("Failed to format message");
+        return {};
+      }
+
+#ifdef DEBUG_ON_STDOUT
+    std::cout << "Status: " << status << std::endl;
+#endif // DEBUG_ON_STDOUT
+
+    return {buffer.data()};
+  }
 };
 
 class I2pSocket {