Add vcpkg cache cleanup step and improve Windows certificate error handling

.github/workflows/test.yaml

@@ -142,6 +142,11 @@ jobs:
         script: |
           core.exportVariable('ACTIONS_CACHE_URL', process.env.ACTIONS_CACHE_URL || '');
           core.exportVariable('ACTIONS_RUNTIME_TOKEN', process.env.ACTIONS_RUNTIME_TOKEN || '');
+    - name: Clean vcpkg cache for different configurations
+      run: |
+        if exist "$env:VCPKG_ROOT\installed" rmdir /s /q "$env:VCPKG_ROOT\installed"
+        if exist "$env:VCPKG_ROOT\packages" rmdir /s /q "$env:VCPKG_ROOT\packages"
+      shell: pwsh
     - name: Setup msbuild on windows
       uses: microsoft/setup-msbuild@v2
     - name: Install vcpkg dependencies
@@ -168,4 +173,4 @@ jobs:
 
     env:
       VCPKG_ROOT: "C:/vcpkg"
-      VCPKG_BINARY_SOURCES: "clear;x-gha,readwrite"
+      VCPKG_BINARY_SOURCES: "clear"

httplib.h

@@ -7295,7 +7295,10 @@ inline bool verify_cert_with_windows_schannel(X509 *server_cert,
           CERT_CHAIN_REVOCATION_ACCUMULATIVE_TIMEOUT,
       nullptr, &chain_context);
 
-  if (!chain_result || !chain_context) { return false; }
+  if (!chain_result || !chain_context) {
+    out_wincrypt_error = GetLastError();
+    return false;
+  }
 
   auto chain_guard =
       detail::scope_exit([&] { CertFreeCertificateChain(chain_context); });
@@ -7305,6 +7308,8 @@ inline bool verify_cert_with_windows_schannel(X509 *server_cert,
 
   // Check if chain has errors
   if (chain_context->TrustStatus.dwErrorStatus != CERT_TRUST_NO_ERROR) {
+    // Set wincrypt_error to the chain trust error
+    out_wincrypt_error = chain_context->TrustStatus.dwErrorStatus;
     return false;
   }