Algo_Registry: Use CRITICAL_SECTION instead of std::mutex to prevent hang in DllMain when initialising global constants.

1 files changed, 49 insertions, 5 deletions

diff --git a/src/lib/base/algo_registry.h b/src/lib/base/algo_registry.h
index e16522d94..2f53d144e 100644
--- a/src/lib/base/algo_registry.h
+++ b/src/lib/base/algo_registry.h
@@ -16,8 +16,36 @@
 #include <string>
 #include <unordered_map>
 
+#if defined(_MSC_VER) && (_MSC_VER <= 1800)
+    #define NOMINMAX 1
+    #define WIN32_LEAN_AND_MEAN 1
+    #include <Windows.h>
+#endif
+
 namespace Botan {
 
+#if defined(_MSC_VER) && (_MSC_VER <= 1800)
+class Windows_Lock
+   {
+   public:
+       Windows_Lock(CRITICAL_SECTION& cs): m_cs(cs)
+          {
+          EnterCriticalSection(&m_cs);
+          }
+          
+       ~Windows_Lock()
+          {
+          LeaveCriticalSection(&m_cs);
+          }
+    private:
+        CRITICAL_SECTION&   m_cs;
+   };
+
+   #define ALGO_REGISTRY_LOCK(_x) Windows_Lock lock(_x)
+#else
+   #define ALGO_REGISTRY_LOCK(_x) std::unique_lock<std::mutex> lock(_x)
+#endif
+
 template<typename T>
 class Algo_Registry
    {
@@ -34,14 +62,14 @@ class Algo_Registry
 
       void add(const std::string& name, const std::string& provider, maker_fn fn, byte pref)
          {
-         std::unique_lock<std::mutex> lock(m_mutex);
+         ALGO_REGISTRY_LOCK(m_mutex);
          if(!m_algo_info[name].add_provider(provider, fn, pref))
             throw std::runtime_error("Duplicated registration of " + name + "/" + provider);
          }
 
       std::vector<std::string> providers_of(const Spec& spec)
          {
-         std::unique_lock<std::mutex> lock(m_mutex);
+         ALGO_REGISTRY_LOCK(m_mutex);
          auto i = m_algo_info.find(spec.algo_name());
          if(i != m_algo_info.end())
             return i->second.providers();
@@ -50,7 +78,7 @@ class Algo_Registry
 
       void set_provider_preference(const Spec& spec, const std::string& provider, byte pref)
          {
-         std::unique_lock<std::mutex> lock(m_mutex);
+         ALGO_REGISTRY_LOCK(m_mutex);
          auto i = m_algo_info.find(spec.algo_name());
          if(i != m_algo_info.end())
             i->second.set_pref(provider, pref);
@@ -92,11 +120,23 @@ class Algo_Registry
          };
 
    private:
-      Algo_Registry() {}
+      Algo_Registry()
+         {
+#if defined(_MSC_VER) && (_MSC_VER <= 1800)
+         InitializeCriticalSection(&m_mutex);
+#endif
+         }
+         
+#if defined(_MSC_VER) && (_MSC_VER <= 1800)
+      ~Algo_Registry()
+         {
+         DeleteCriticalSection(&m_mutex);
+         }
+#endif
 
       std::vector<maker_fn> get_makers(const Spec& spec, const std::string& provider)
          {
-         std::unique_lock<std::mutex> lock(m_mutex);
+         ALGO_REGISTRY_LOCK(m_mutex);
          return m_algo_info[spec.algo_name()].get_makers(provider);
          }
 
@@ -158,7 +198,11 @@ class Algo_Registry
             std::unordered_map<std::string, maker_fn> m_maker_fns;
          };
 
+#if defined(_MSC_VER) && (_MSC_VER <= 1800)
+      CRITICAL_SECTION m_mutex;
+#else
       std::mutex m_mutex;
+#endif
       std::unordered_map<std::string, Algo_Info> m_algo_info;
    };