engine: implement platform neutral saves, now we can load saves made in Linux on Windows and vice-versa

engine/common/lib_common.c

@@ -17,6 +17,7 @@ GNU General Public License for more details.
 #include "library.h"
 #include "filesystem.h"
 #include "server.h"
+#include <ctype.h>
 
 static char s_szLastError[1024] = "";
 
@@ -39,10 +40,35 @@ void COM_PushLibraryError( const char *error )
 
 void *COM_FunctionFromName_SR( void *hInstance, const char *pName )
 {
+	char **funcs = NULL;
+	size_t numfuncs, i;
+	void *f = NULL;
+
 #ifdef XASH_ALLOW_SAVERESTORE_OFFSETS
 	if( !memcmp( pName, "ofs:",4 ) )
 		return (byte*)svgame.dllFuncs.pfnGameInit + Q_atoi(pName + 4);
 #endif
+
+#if XASH_MSVC && XASH_X86
+	funcs = COM_ConvertToLocalPlatform( MANGLE_VALVE, pName, &numfuncs );
+#elif XASH_POSIX
+	funcs = COM_ConvertToLocalPlatform( MANGLE_ITANIUM, pName, &numfuncs );
+#endif
+
+	if( funcs )
+	{
+		for( i = 0; i < numfuncs; i++ )
+		{
+			f = COM_FunctionFromName( hInstance, funcs[i] );
+			Z_Free( funcs[i] );
+			if( f )
+				break;
+		}
+		Z_Free( funcs );
+
+		if( f ) return f;
+	}
+
 	return COM_FunctionFromName( hInstance, pName );
 }
 
@@ -175,3 +201,322 @@ void COM_GetCommonLibraryPath( ECommonLibraryType eLibType, char *out, size_t si
 		break;
 	}
 }
+
+/*
+=============================================================================
+
+	C++ MANGLE CONVERSION
+
+=============================================================================
+*/
+#define MAX_NESTED_NAMESPACES 16 /* MSVC limit */
+
+static EFunctionMangleType COM_DetectMangleType( const char *str )
+{
+	// Itanium C++ ABI mangling always start with _Z
+	// namespaces start with N, therefore _ZN
+	if( !Q_strncmp( str, "_ZN", 3 ) )
+		return MANGLE_ITANIUM;
+
+	// MSVC C++ mangling always start with ? and have
+	if( str[0] == '?' && Q_strstr( str, "@@" ))
+		return MANGLE_MSVC;
+
+	// allow offsets, we just silently ignore them on conversion
+	if( !Q_strncmp( str, "ofs:", 4 ))
+		return MANGLE_OFFSET;
+
+	// don't get confused by MSVC C mangling
+	if( str[0] != '@' && Q_strchr( str, '@' ))
+		return MANGLE_VALVE;
+
+	// not technically an error
+	return MANGLE_UNKNOWN;
+}
+
+char *COM_GetMSVCName( const char *in_name )
+{
+	static string   out_name;
+	char            *pos;
+
+	if( in_name[0] == '?' )  // is this a MSVC C++ mangled name?
+	{
+		if(( pos = Q_strstr( in_name, "@@" )) != NULL )
+		{
+			ptrdiff_t len = pos - in_name;
+
+			// strip off the leading '?'
+			Q_strncpy( out_name, in_name + 1, sizeof( out_name ));
+			out_name[len-1] = 0; // terminate string at the "@@"
+			return out_name;
+		}
+	}
+
+	Q_strncpy( out_name, in_name, sizeof( out_name ));
+
+	return out_name;
+}
+
+static char *COM_GetItaniumName( const char * const in_name )
+{
+	static string out_name;
+	const char *f = in_name;
+	string symbols[16];
+	uint len = 0;
+	int i;
+	int remaining;
+
+	remaining = Q_strlen( f );
+
+	if( remaining < 3 )
+		goto invalid_format;
+
+	out_name[0] = 0;
+
+	// skip _ZN
+	f += 3;
+	remaining -= 3;
+
+	for( i = 0; i < MAX_NESTED_NAMESPACES; i++ )
+	{
+		// parse symbol length marker
+		len = 0;
+		for( ; isdigit( *f ) && remaining > 0; f++, remaining-- )
+			len = len * 10 + ( *f - '0' );
+
+		// sane value
+		len = min( remaining, len );
+
+		if( len == 0 )
+			goto invalid_format;
+
+		Q_strncpy( symbols[i], f, min( len + 1, sizeof( out_name )));
+		f += len;
+		remaining -= len;
+
+		// end marker
+		if( *f == 'E' )
+			break;
+
+		if( !isdigit( *f ) || remaining <= 0 )
+			goto invalid_format;
+	}
+
+	if( i == MAX_NESTED_NAMESPACES )
+	{
+		Con_DPrintf( "%s: too much nested namespaces: %s\n", __FUNCTION__, in_name );
+		return NULL;
+	}
+
+	for( ; i >= 0; i-- )
+	{
+		Q_strncat( out_name, symbols[i], sizeof( out_name ));
+		if( i > 0 )
+			Q_strncat( out_name, "@", sizeof( out_name ));
+	}
+
+	return out_name;
+
+invalid_format:
+	Con_DPrintf( "%s: invalid format: %s\n", __FUNCTION__, in_name );
+	return NULL;
+}
+
+char **COM_ConvertToLocalPlatform( EFunctionMangleType to, const char *from, size_t *numfuncs )
+{
+	string symbols[MAX_NESTED_NAMESPACES], temp, temp2;
+	const char *prev;
+	const char *postfix[3];
+	int i = 0;
+	char **ret;
+
+	// TODO:
+	if( to == MANGLE_MSVC )
+		return NULL;
+
+	switch( to )
+	{
+	case MANGLE_ITANIUM:
+		postfix[0] = "Ev";
+		postfix[1] = "EP11CBaseEntity";
+		postfix[2] = "EP11CBaseEntityS1_8USE_TYPEf";
+		break;
+	default:
+		ASSERT( 0 );
+		return NULL;
+	}
+
+	prev = from;
+
+	for( i = 0; i < MAX_NESTED_NAMESPACES; i++ )
+	{
+		const char *at = Q_strchr( prev, '@' );
+		uint len;
+
+		if( at ) len = (uint)( at - prev );
+		else len = (uint)Q_strlen( prev );
+		Q_strncpy( symbols[i], prev, min( len + 1, sizeof( symbols[i] )));
+		prev = at + 1;
+
+		if( !at )
+			break;
+	}
+
+	if( i == MAX_NESTED_NAMESPACES )
+	{
+		Con_DPrintf( "%s: too much nested namespaces: %s\n", __FUNCTION__, from );
+		return NULL;
+	}
+
+	// only three possible variations
+	*numfuncs = ARRAYSIZE( postfix );
+	ret = Z_Malloc( sizeof( char * ) * ARRAYSIZE( postfix ) );
+
+	Q_strncpy( temp, "_ZN", sizeof( temp ));
+
+	for( ; i >= 0; i-- )
+	{
+		Q_snprintf( temp2, sizeof( temp2 ), "%u%s", (uint)Q_strlen( symbols[i] ), symbols[i] );
+		Q_strncat( temp, temp2, sizeof( temp ));
+	}
+
+	for( i = 0; i < ARRAYSIZE( postfix ); i++ )
+	{
+		Q_snprintf( temp2, sizeof( temp2 ), "%s%s", temp, postfix[i] );
+		ret[i] = copystring( temp2 );
+	}
+
+	return ret;
+}
+
+const char *COM_GetPlatformNeutralName( const char *in_name )
+{
+	EFunctionMangleType type = COM_DetectMangleType( in_name );
+
+	switch( type )
+	{
+	case MANGLE_ITANIUM: return COM_GetItaniumName( in_name );
+	case MANGLE_MSVC: return COM_GetMSVCName( in_name );
+	default: return in_name;
+	}
+}
+
+#if XASH_ENGINE_TESTS
+#include "tests.h"
+
+static void Test_DetectMangleType( void )
+{
+	TASSERT(COM_DetectMangleType( "asdf" ) == MANGLE_UNKNOWN );
+	TASSERT(COM_DetectMangleType( "012345" ) == MANGLE_UNKNOWN );
+	TASSERT(COM_DetectMangleType( "?asdf" ) == MANGLE_UNKNOWN );
+	TASSERT(COM_DetectMangleType( "_Zasdf" ) == MANGLE_UNKNOWN );
+
+	TASSERT(COM_DetectMangleType( "ofs:1234" ) == MANGLE_OFFSET );
+	TASSERT(COM_DetectMangleType( "ofs:asdf" ) == MANGLE_OFFSET );
+	TASSERT(COM_DetectMangleType( "ofs:" ) == MANGLE_OFFSET );
+
+	TASSERT(COM_DetectMangleType( "_ZN1f1fEv" ) == MANGLE_ITANIUM );
+	TASSERT(COM_DetectMangleType( "_ZN3foo3barEv" ) == MANGLE_ITANIUM );
+
+	TASSERT(COM_DetectMangleType( "?f@f@@msvcsucks" ) == MANGLE_MSVC );
+	TASSERT(COM_DetectMangleType( "?foo@bar@@IHATEMSVC" ) == MANGLE_MSVC );
+
+	TASSERT(COM_DetectMangleType( "f@f" ) == MANGLE_VALVE );
+	TASSERT(COM_DetectMangleType( "foo@bar" ) == MANGLE_VALVE );
+
+	// Xash3D FWGS extensions test
+	TASSERT(COM_DetectMangleType( "_ZN1f1f1fEv" ) == MANGLE_ITANIUM );
+	TASSERT(COM_DetectMangleType( "_ZN3foo3bar3bazEv" ) == MANGLE_ITANIUM );
+
+	TASSERT(COM_DetectMangleType( "?f@f@f@@msvcsucks" ) == MANGLE_MSVC );
+	TASSERT(COM_DetectMangleType( "?foo@bar@@IHATEMSVC" ) == MANGLE_MSVC );
+
+	TASSERT(COM_DetectMangleType( "f@f@f" ) == MANGLE_VALVE );
+	TASSERT(COM_DetectMangleType( "foo@bar@baz" ) == MANGLE_VALVE );
+}
+
+static void Test_GetMSVCName( void )
+{
+	const char *symbols[] =
+	{
+		"", "",
+		"?f@f@@XYZA", "f@f",
+		"?foo@bar@@QAEXXZ", "foo@bar",
+		"foo", "foo",
+		"?foo", "?foo",
+		"?foo@@", "foo", // not an error?
+		"?foo@bar@baz@@gotstrippedanyway","foo@bar@baz"
+	};
+	int i;
+
+	for( i = 0; i < ARRAYSIZE( symbols ); i += 2 )
+	{
+		Msg( "Checking if MSVC '%s' converts to '%s'...\n", symbols[i], symbols[i+1] );
+
+		TASSERT( !Q_strcmp( COM_GetMSVCName( symbols[i] ), symbols[i+1] ));
+	}
+}
+
+static void Test_GetItaniumName( void )
+{
+	const char *symbols[] =
+	{
+		"", NULL,
+		"_", NULL,
+		"_Z", NULL,
+		"_ZN", NULL,
+		"_ZNv", NULL,
+		"_ZN4barr3foo", NULL,
+		"_ZN3bar3foov", NULL,
+		"_ZN4bar3fooEv", NULL,
+		"_ZN3bar3fooEv", "foo@bar",
+		"_Z3foov", NULL,
+		"_ZN3fooEv", "foo", // not possible?
+		"_ZN3baz3bar3fooEdontcare", "foo@bar@baz",
+	};
+	int i;
+
+	for( i = 0; i < ARRAYSIZE( symbols ); i += 2 )
+	{
+		Msg( "Checking if Itanium '%s' converts to '%s'...\n", symbols[i], symbols[i+1] );
+
+		TASSERT( !Q_strcmp( COM_GetItaniumName( symbols[i] ), symbols[i+1] ));
+	}
+}
+
+static void Test_ConvertFromValveToLocal( void )
+{
+	const char *symbols[] =
+	{
+		"", "_ZN",
+		"foo", "_ZN3foo",
+		"xash3d@fwgs", "_ZN4fwgs6xash3d",
+		"foo@bar@bazz", "_ZN4bazz3bar3foo"
+	};
+	int i;
+
+	for( i = 0; i < ARRAYSIZE( symbols ); i += 2 )
+	{
+		char **ret;
+		size_t numfuncs;
+		size_t symlen = Q_strlen( symbols[i + 1] );
+
+		Msg( "Checking if Valve '%s' converts to Itanium '%s'...\n", symbols[i], symbols[i+1] );
+
+		ret = COM_ConvertToLocalPlatform( MANGLE_ITANIUM, symbols[i], &numfuncs );
+
+		TASSERT( numfuncs == 3 );
+		TASSERT( !Q_strncmp( ret[0], symbols[i+1], symlen ));
+		TASSERT( !Q_strncmp( ret[1], symbols[i+1], symlen ));
+		TASSERT( !Q_strncmp( ret[2], symbols[i+1], symlen ));
+	}
+}
+
+void Test_RunLibCommon( void )
+{
+	TRUN( Test_DetectMangleType() );
+	TRUN( Test_GetMSVCName() );
+	TRUN( Test_GetItaniumName() );
+	TRUN( Test_ConvertFromValveToLocal() );
+}
+#endif /* XASH_ENGINE_TESTS */

engine/common/library.h

@@ -58,4 +58,31 @@ typedef enum
 
 void COM_GetCommonLibraryPath( ECommonLibraryType eLibType, char *out, size_t size );
 
+typedef enum
+{
+	MANGLE_UNKNOWN = 0,
+
+	/* binary offset, when NameForFunction isn't implemented */
+	MANGLE_OFFSET,
+
+	/* Itanium C++ ABI mangling, native for most operating systems */
+	MANGLE_ITANIUM,
+
+	/* MSVC "decoration" */
+	MANGLE_MSVC,
+
+	/* Valve's silly mangle for crossplatform saves */
+	MANGLE_VALVE,
+} EFunctionMangleType;
+
+// converts to MANGLE_VALVE if possible
+const char *COM_GetPlatformNeutralName( const char *in_name );
+
+// converts to native mangling, result must be freed
+char **COM_ConvertToLocalPlatform( EFunctionMangleType to, const char *from, size_t *numfuncs );
+
+// used by lib_win.c
+char *COM_GetMSVCName( const char *in_name );
+
+
 #endif//LIBRARY_H

engine/platform/posix/lib_posix.c

@@ -220,15 +220,16 @@ const char *COM_NameForFunction( void *hInstance, void *function )
 #ifdef XASH_DLL_LOADER
 	void *wm;
 	if( host.enabledll && (wm = Loader_GetDllHandle( hInstance )) )
+#error ConvertMangledName
 		return Loader_GetFuncName_int(wm, function);
 	else
 #endif
 	// NOTE: dladdr() is a glibc extension
 	{
 		Dl_info info = {0};
-		dladdr((void*)function, &info);
-		if(info.dli_sname)
-			return info.dli_sname;
+		dladdr( (void*)function, &info );
+		if( info.dli_sname )
+			return COM_GetPlatformNeutralName( info.dli_sname );
 	}
 #ifdef XASH_ALLOW_SAVERESTORE_OFFSETS
 	return COM_OffsetNameForFunction( function );