System: Hash executable for game code when system.cnf missing

src/core/system.cpp

@@ -32,6 +32,7 @@
 #include "spu.h"
 #include "texture_replacements.h"
 #include "timers.h"
+#include "xxhash.h"
 #include <cctype>
 #include <cinttypes>
 #include <cmath>
@@ -385,39 +386,57 @@ std::string_view GetTitleForPath(const char* path)
   return path_view.substr(0, path_view.find_last_of('.'));
 }
 
-std::string GetGameCodeForPath(const char* image_path)
+std::string GetGameCodeForPath(const char* image_path, bool fallback_to_hash)
 {
   std::unique_ptr<CDImage> cdi = CDImage::Open(image_path);
   if (!cdi)
     return {};
 
-  return GetGameCodeForImage(cdi.get());
+  return GetGameCodeForImage(cdi.get(), fallback_to_hash);
 }
 
-std::string GetGameCodeForImage(CDImage* cdi)
+std::string GetGameCodeForImage(CDImage* cdi, bool fallback_to_hash)
 {
   std::string code(GetExecutableNameForImage(cdi));
-  if (code.empty())
-    return {};
-
-  // SCES_123.45 -> SCES-12345
-  for (std::string::size_type pos = 0; pos < code.size();)
+  if (!code.empty())
   {
-    if (code[pos] == '.')
+    // SCES_123.45 -> SCES-12345
+    for (std::string::size_type pos = 0; pos < code.size();)
     {
-      code.erase(pos, 1);
-      continue;
+      if (code[pos] == '.')
+      {
+        code.erase(pos, 1);
+        continue;
+      }
+
+      if (code[pos] == '_')
+        code[pos] = '-';
+      else
+        code[pos] = static_cast<char>(std::toupper(code[pos]));
+
+      pos++;
     }
 
-    if (code[pos] == '_')
-      code[pos] = '-';
-    else
-      code[pos] = static_cast<char>(std::toupper(code[pos]));
-
-    pos++;
+    return code;
   }
 
-  return code;
+  if (!fallback_to_hash)
+    return {};
+
+  std::string exe_name;
+  std::vector<u8> exe_buffer;
+  if (!ReadExecutableFromImage(cdi, &exe_name, &exe_buffer))
+    return {};
+
+  XXH64_state_t* state = XXH64_createState();
+  XXH64_reset(state, 0x4242D00C);
+  XXH64_update(state, exe_name.c_str(), exe_name.size());
+  XXH64_update(state, exe_buffer.data(), exe_buffer.size());
+  const u64 hash = XXH64_digest(state);
+  XXH64_freeState(state);
+
+  Log_InfoPrintf("Hash for '%s' - %" PRIX64, exe_name.c_str(), hash);
+  return StringUtil::StdStringFromFormat("HASH-%" PRIX64, hash);
 }
 
 static std::string GetExecutableNameForImage(CDImage* cdi, ISOReader& iso, bool strip_subdirectories)
@@ -601,7 +620,7 @@ DiscRegion GetRegionForImage(CDImage* cdi)
   if (system_area_region != DiscRegion::Other)
     return system_area_region;
 
-  std::string code = GetGameCodeForImage(cdi);
+  std::string code = GetGameCodeForImage(cdi, false);
   if (code.empty())
     return DiscRegion::Other;
 

src/core/system.h

@@ -78,8 +78,8 @@ ConsoleRegion GetConsoleRegionForDiscRegion(DiscRegion region);
 std::string GetExecutableNameForImage(CDImage* cdi);
 bool ReadExecutableFromImage(CDImage* cdi, std::string* out_executable_name, std::vector<u8>* out_executable_data);
 
-std::string GetGameCodeForImage(CDImage* cdi);
-std::string GetGameCodeForPath(const char* image_path);
+std::string GetGameCodeForImage(CDImage* cdi, bool fallback_to_hash);
+std::string GetGameCodeForPath(const char* image_path, bool fallback_to_hash);
 DiscRegion GetRegionForCode(std::string_view code);
 DiscRegion GetRegionFromSystemArea(CDImage* cdi);
 DiscRegion GetRegionForImage(CDImage* cdi);

src/frontend-common/common_host_interface.cpp

@@ -415,7 +415,7 @@ bool CommonHostInterface::ParseCommandLineParameters(int argc, char* argv[],
       else
       {
         // find the game id, and get its save state path
-        std::string game_code = System::GetGameCodeForPath(boot_filename.c_str());
+        std::string game_code = System::GetGameCodeForPath(boot_filename.c_str(), true);
         if (game_code.empty())
         {
           Log_WarningPrintf("Could not identify game code for '%s', cannot load save state %d.", boot_filename.c_str(),
@@ -2867,7 +2867,7 @@ void CommonHostInterface::GetGameInfo(const char* path, CDImage* image, std::str
   else
   {
     if (image)
-      *code = System::GetGameCodeForImage(image);
+      *code = System::GetGameCodeForImage(image, true);
 
     const GameListDatabaseEntry* db_entry = (!code->empty()) ? m_game_list->GetDatabaseEntryForCode(*code) : nullptr;
     if (db_entry)

src/frontend-common/game_list.cpp

@@ -181,7 +181,7 @@ bool GameList::GetM3UListEntry(const char* path, GameListEntry* entry)
 
     if (entry->compatibility_rating == GameListCompatibilityRating::Unknown)
     {
-      std::string code = System::GetGameCodeForImage(entry_image.get());
+      std::string code = System::GetGameCodeForImage(entry_image.get(), true);
       const GameListCompatibilityEntry* compatibility_entry = GetCompatibilityEntryForCode(entry->code);
       if (compatibility_entry)
         entry->compatibility_rating = compatibility_entry->compatibility_rating;
@@ -206,7 +206,7 @@ bool GameList::GetGameListEntry(const std::string& path, GameListEntry* entry)
   if (!cdi)
     return false;
 
-  std::string code = System::GetGameCodeForImage(cdi.get());
+  std::string code = System::GetGameCodeForImage(cdi.get(), true);
   DiscRegion region = System::GetRegionFromSystemArea(cdi.get());
   if (region == DiscRegion::Other)
     region = System::GetRegionForCode(code);