don't load the same PDB twice

2 files changed, 34 insertions, 0 deletions

diff --git a/include/pdb/repo.hpp b/include/pdb/repo.hpp
index 239bd7e..aa5c3c3 100644
--- a/include/pdb/repo.hpp
+++ b/include/pdb/repo.hpp
@@ -9,10 +9,12 @@
 #include "dbghelp.hpp"
 #include "module.hpp"
 #include "symbol.hpp"
+#include "utils/file.hpp"
 
 #include <functional>
 #include <map>
 #include <string>
+#include <unordered_set>
 
 namespace pdb
 {
@@ -45,5 +47,7 @@ namespace pdb
 
         std::map<Address, Module> online_modules;
         std::map<Address, const Module&> offline_modules;
+
+        std::unordered_set<file::ID> module_ids;
     };
 }
diff --git a/include/pdb/utils/file.hpp b/include/pdb/utils/file.hpp
index 5b83f2b..50975aa 100644
--- a/include/pdb/utils/file.hpp
+++ b/include/pdb/utils/file.hpp
@@ -5,14 +5,44 @@
 
 #pragma once
 
+#include <Windows.h>
+
 #include <cstddef>
+#include <cstring>
 
+#include <functional>
 #include <string>
+#include <type_traits>
 
 namespace pdb
 {
     namespace file
     {
         std::size_t get_size(const std::string&);
+
+        struct ID
+        {
+            const FILE_ID_INFO raw;
+
+            bool operator==(const ID& other) const
+            {
+                static_assert(std::is_pod<FILE_ID_INFO>::value, "Can't memcmp if file IDs aren't PODs");
+                return 0 == std::memcmp(&raw, &other.raw, sizeof(FILE_ID_INFO));
+            }
+        };
+
+        ID query_id(const std::string&);
     }
 }
+
+namespace std
+{
+    template <>
+    struct hash<pdb::file::ID>
+    {
+        std::size_t operator()(const pdb::file::ID& id) const
+        {
+            return _Bitwise_hash<FILE_ID_INFO>{}(id.raw);
+        }
+    };
+}