Load localized strings in IW4M

PatchMW2LocalizedStrings.cpp

// ==========================================================
// IW4M project
// 
// Component: clientdll
// Sub-component: steam_api
// Purpose: Code to replace localized strings in the game.
//
// Initial author: NTAuthority
// Edited by zxz0O0 to add the ability of loading custom str files
// Started: 2013-01-17
// ==========================================================

#include "StdInc.h"
#include <google/dense_hash_map>

struct localizedEntry_s
{
  const char* value;
	const char* name;
};

StompHook loadLocalizeHook;
DWORD loadLocalizeHookLoc = 0x629B90;

static google::dense_hash_map<std::string, std::string> _localizedStrings;

int LoadStrFiles(char* language)
{
	char buf[256];
	sprintf_s(buf, sizeof(buf), "%s/localizedstrings/", language);
	int count;
	char** list = FS_ListFiles(buf, "str", 0, &count);
	for(int i = 0;i < count;i++)
	{
		sprintf_s(buf, sizeof(buf), "%s/localizedstrings/%s", language, list[i]);
		Com_Printf(0, "Parsing localized string file: %s\n", buf);
		char* Error = SE_Load(buf, 0);
		if(Error)
			Com_Printf(0, "Error parsing localized string file: %s\n", Error);
	}
	FS_FreeFileList(list);

	return count;
}

void SELoadLanguageHookStub()
{
	_localizedStrings.clear();

	//get language from loc_modLanguage
	dvar_t* modLang = Dvar_FindVar("loc_modLanguage");
	char** enumList = *(char***)&(modLang->max); //not sure if this is really dvar_maxmin_t max.
	char* language = enumList[modLang->current.integer];

	//'official' iw4m localized strings
	SE_Load("localizedstrings/iw4m.str", 0);

	if(LoadStrFiles(language)==0)
		LoadStrFiles("english");//load english str files if there aren't any of selected language

	__asm
	{
		leave
		mov eax, 0x41D885 //back to SE_LoadLanguage
		jmp eax
	}
}

//can't use dense_hash_map in a naked
void AddCustomString(char* key, char* value)
{
	_localizedStrings[key] = value;
}

void __declspec(naked) SetString(char* key, char* value, bool isEnglish)
{
	__asm
	{
		push [esp+8]
		push [esp+8]
		call AddCustomString
		add esp,8
		mov eax,[esp] //get return address
		add esp,0x10 //remove stack space for parameters + return address
		jmp eax //return
	}
}

const char* SEH_GetLocalizedString(const char* key)
{
	google::dense_hash_map<std::string, std::string>::const_iterator iter = _localizedStrings.find(key);

	if (iter != _localizedStrings.end())
	{
		return (*iter).second.c_str();
	}

	localizedEntry_s* entry = (localizedEntry_s*)DB_FindXAssetHeader(ASSET_TYPE_LOCALIZE, key);

	if (entry)
	{
		return entry->value;
	}
	
	return NULL;
}

//loc_language codes
//"english", "french", "german", "italian", "spanish", "british", "russian", "polish", "korean", "taiwanese", "japanese", "chinese", "thai", "leet", "czech"
char* ModLanguageEnum[] = { "english", "french", "german", "italian", "spanish", "english", "russian", "polish",  0 };

void PatchMW2_LocalizedStrings()
{
	_localizedStrings.set_empty_key("");

	loadLocalizeHook.initialize(loadLocalizeHookLoc, SEH_GetLocalizedString);
	loadLocalizeHook.installHook();

	call(0x4CE5EE, SetString, PATCH_CALL); //instead of calling CStringEdPackage::SetString in CStringEdPackage::ParseLine we call our SetString
	call(0x41D860, SELoadLanguageHookStub, PATCH_JUMP); //instead of the game loading str files according to loc_language we load them according to loc_modlanguage

	Dvar_RegisterEnum("loc_modLanguage", ModLanguageEnum, 0, DVAR_FLAG_SAVED, "Preferred language for custom localized strings.");
}