From c6d553b2a2d39bc98773ab26659acc1901064dfa Mon Sep 17 00:00:00 2001
From: Sushrut Shringarputale <sushring@microsoft.com>
Date: Tue, 20 May 2025 21:59:01 -0700
Subject: [PATCH] Fix Windows error for failing curl SSL cache (#6582)

* Fix Windows error for failing curl SSL cache

* Fix unused parameter warning in win_http_transport.cpp, as in #6579

* Update changelog, cspell, and conditional init m_sslShareHandle

---------

Co-authored-by: Anton Kolesnyk <antkmsft@users.noreply.github.com>
---
 .vscode/cspell.json                           |  1 +
 sdk/core/azure-core/CHANGELOG.md              |  2 +-
 sdk/core/azure-core/src/http/curl/curl.cpp    | 19 ++++++++++---------
 .../src/http/winhttp/win_http_transport.cpp   |  4 ++++
 4 files changed, 16 insertions(+), 10 deletions(-)

diff --git a/.vscode/cspell.json b/.vscode/cspell.json
index f223e1a56..5df529dd9 100644
--- a/.vscode/cspell.json
+++ b/.vscode/cspell.json
@@ -263,6 +263,7 @@
     "stoull",
     "STREQ",
     "Sushrut",
+    "sushshring",
     "Sutou",
     "testid",
     "swedencentral",
diff --git a/sdk/core/azure-core/CHANGELOG.md b/sdk/core/azure-core/CHANGELOG.md
index eabb0e43c..7724d5891 100644
--- a/sdk/core/azure-core/CHANGELOG.md
+++ b/sdk/core/azure-core/CHANGELOG.md
@@ -4,7 +4,7 @@
 
 ### Features Added
 
-- [[#6535]](https://github.com/Azure/azure-sdk-for-cpp/issues/6535) Enable SSL caching for libcurl transport by default, which is backwards compatible behavior with older libcurl versions, so using the default settings won't result in transport error when using libcurl >= 8.12. The option is controlled by `CurlTransportOptions::EnableCurlSslCaching`, and is on by default. (A community contribution, courtesy of _[chewi](https://github.com/sushshring)_)
+- [[#6535]](https://github.com/Azure/azure-sdk-for-cpp/issues/6535) Enable SSL caching for libcurl transport by default, which is backwards compatible behavior with older libcurl versions, so using the default settings won't result in transport error when using libcurl >= 8.12. The option is controlled by `CurlTransportOptions::EnableCurlSslCaching`, and is on by default. (A community contribution, courtesy of _[sushshring](https://github.com/sushshring)_)
 
 ### Breaking Changes
 
diff --git a/sdk/core/azure-core/src/http/curl/curl.cpp b/sdk/core/azure-core/src/http/curl/curl.cpp
index 3ca3ef575..b97d898a7 100644
--- a/sdk/core/azure-core/src/http/curl/curl.cpp
+++ b/sdk/core/azure-core/src/http/curl/curl.cpp
@@ -2314,14 +2314,6 @@ CurlConnection::CurlConnection(
   }
   CURLcode result;
 
-  m_sslShareHandle = std::make_unique<Azure::Core::_detail::CURLSHWrapper>();
-  if (!m_sslShareHandle->share_handle)
-  {
-    throw Azure::Core::Http::TransportException(
-        _detail::DefaultFailedToGetNewConnectionTemplate + hostDisplayName + ". "
-        + std::string("curl_share_init returned Null"));
-  }
-
   if (!options.EnableCurlSslCaching)
   {
     // Disable SSL session ID caching
@@ -2334,6 +2326,15 @@ CurlConnection::CurlConnection(
   }
   else
   {
+    m_sslShareHandle = std::make_unique<Azure::Core::_detail::CURLSHWrapper>();
+
+    if (!m_sslShareHandle->share_handle)
+    {
+      throw Azure::Core::Http::TransportException(
+          _detail::DefaultFailedToGetNewConnectionTemplate + hostDisplayName + ". "
+          + std::string("curl_share_init returned Null"));
+    }
+
     CURLSHcode shResult;
     if (!SetLibcurlShareOption(
             m_sslShareHandle, CURLSHOPT_SHARE, CURL_LOCK_DATA_SSL_SESSION, &shResult))
@@ -2343,7 +2344,7 @@ CurlConnection::CurlConnection(
           + std::string(curl_share_strerror(shResult)));
     }
 
-    if (!SetLibcurlOption(m_handle, CURLOPT_SHARE, m_sslShareHandle.get(), &result))
+    if (!SetLibcurlOption(m_handle, CURLOPT_SHARE, m_sslShareHandle->share_handle, &result))
     {
       throw Azure::Core::Http::TransportException(
           _detail::DefaultFailedToGetNewConnectionTemplate + hostDisplayName + ". "
diff --git a/sdk/core/azure-core/src/http/winhttp/win_http_transport.cpp b/sdk/core/azure-core/src/http/winhttp/win_http_transport.cpp
index 342cc3531..3ff991e70 100644
--- a/sdk/core/azure-core/src/http/winhttp/win_http_transport.cpp
+++ b/sdk/core/azure-core/src/http/winhttp/win_http_transport.cpp
@@ -1670,6 +1670,10 @@ namespace Azure { namespace Core { namespace Http { namespace _detail {
 
   std::unique_ptr<RawResponse> WinHttpRequest::SendRequestAndGetResponse(HttpMethod requestMethod)
   {
+    // Suppress unused parameter warning (C4100).
+    // Keeping 'requestMethod' in the signature preserves API compatibility.
+    (void)requestMethod;
+
     // First, use WinHttpQueryHeaders to obtain the size of the buffer.
     // The call is expected to fail since no destination buffer is provided.
     DWORD sizeOfHeaders = 0;