public: add dll helpers to simplify basic interaction with exported functions lists

common/xash3d_types.h

@@ -232,6 +232,7 @@ typedef struct dll_info_s
 {
 	const char	*name;	// name of library
 	const dllfunc_t	*fcts;	// list of dll exports
+	const size_t num_fcts;
 	qboolean		crash;	// crash if dll not found
 	void		*link;	// hinstance of loading library
 } dll_info_t;

engine/client/avi/avi_win.c

@@ -30,10 +30,9 @@ static dllfunc_t msvfw_funcs[] =
 { "DrawDibOpen", (void **) &pDrawDibOpen },
 { "DrawDibDraw", (void **) &pDrawDibDraw },
 { "DrawDibClose", (void **) &pDrawDibClose },
-{ NULL, NULL }
 };
 
-dll_info_t msvfw_dll = { "msvfw32.dll", msvfw_funcs, false };
+dll_info_t msvfw_dll = { "msvfw32.dll", msvfw_funcs, ARRAYSIZE( msvfw_funcs ), false };
 
 // msacm32.dll exports
 static MMRESULT (_stdcall *pacmStreamOpen)( LPHACMSTREAM, HACMDRIVER, LPWAVEFORMATEX, LPWAVEFORMATEX, LPWAVEFILTER, DWORD, DWORD, DWORD );
@@ -51,10 +50,9 @@ static dllfunc_t msacm_funcs[] =
 { "acmStreamConvert", (void **) &pacmStreamConvert },
 { "acmStreamSize", (void **) &pacmStreamSize },
 { "acmStreamClose", (void **) &pacmStreamClose },
-{ NULL, NULL }
 };
 
-dll_info_t msacm_dll = { "msacm32.dll", msacm_funcs, false };
+dll_info_t msacm_dll = { "msacm32.dll", msacm_funcs, ARRAYSIZE( msacm_funcs ), false };
 
 // avifil32.dll exports
 static int (_stdcall *pAVIStreamInfo)( PAVISTREAM pavi, AVISTREAMINFO *psi, LONG lSize );
@@ -88,10 +86,9 @@ static dllfunc_t avifile_funcs[] =
 { "AVIStreamRelease", (void **) &pAVIStreamRelease },
 { "AVIStreamStart", (void **) &pAVIStreamStart },
 { "AVIStreamTimeToSample", (void **) &pAVIStreamTimeToSample },
-{ NULL, NULL }
 };
 
-dll_info_t avifile_dll = { "avifil32.dll", avifile_funcs, false };
+dll_info_t avifile_dll = { "avifil32.dll", avifile_funcs, ARRAYSIZE( avifile_funcs ), false };
 
 typedef struct movie_state_s
 {

engine/client/cl_game.c

@@ -4062,8 +4062,7 @@ qboolean CL_LoadProgs( const char *name )
 	}
 
 	// clear exports
-	for( i = 0; i < ARRAYSIZE( cdll_exports ); i++ )
+	ClearExports( cdll_exports, ARRAYSIZE( cdll_exports ));
-		*(cdll_exports[i].func) = NULL;
 
 	// trying to get single export
 	if(( GetClientAPI = (void *)COM_GetProcAddress( clgame.hInstance, "GetClientAPI" )) != NULL )
@@ -4081,19 +4080,8 @@ qboolean CL_LoadProgs( const char *name )
 		CL_GetSecuredClientAPI( GetClientAPI );
 	}
 
-	if( GetClientAPI != NULL )
+	if( GetClientAPI != NULL ) // check critical functions again
-	{
+		valid_single_export = ValidateExports( cdll_exports, ARRAYSIZE( cdll_exports ));
-		// check critical functions again
-		for( i = 0; i < ARRAYSIZE( cdll_exports ); i++ )
-		{
-			if( *(cdll_exports[i].func) == NULL )
-				break; // BAH critical function was missed
-		}
-
-		// everything was loaded
-		if( i == ARRAYSIZE( cdll_exports ))
-			valid_single_export = true;
-	}
 
 	for( i = 0; i < ARRAYSIZE( cdll_exports ); i++ )
 	{
@@ -4119,11 +4107,7 @@ qboolean CL_LoadProgs( const char *name )
 
 	// it may be loaded through 'GetClientAPI' so we don't need to clear them
 	if( !valid_single_export )
-	{
+		ClearExports( cdll_new_exports, ARRAYSIZE( cdll_new_exports ));
-		// clear new exports
-		for( i = 0; i < ARRAYSIZE( cdll_new_exports ); i++ )
-			*(cdll_new_exports[i].func) = NULL;
-	}
 
 	for( i = 0; i < ARRAYSIZE( cdll_new_exports ); i++ )
 	{

engine/common/system.c

@@ -255,7 +255,7 @@ void Sys_SendKeyEvents( void )
 //=======================================================================
 qboolean Sys_LoadLibrary( dll_info_t *dll )
 {
-	const dllfunc_t	*func;
+	size_t i;
 	string		errorstring;
 
 	// check errors
@@ -267,12 +267,8 @@ qboolean Sys_LoadLibrary( dll_info_t *dll )
 
 	Con_Reportf( "%s: Loading %s", __func__, dll->name );
 
-	if( dll->fcts )
+	if( dll->fcts ) // lookup export table
-	{
+		ClearExports( dll->fcts, dll->num_fcts );
-		// lookup export table
-		for( func = dll->fcts; func && func->name != NULL; func++ )
-			*func->func = NULL;
-	}
 
 	if( !dll->link )
 		dll->link = COM_LoadLibrary( dll->name, false, true ); // environment pathes
@@ -285,9 +281,10 @@ qboolean Sys_LoadLibrary( dll_info_t *dll )
 	}
 
 	// Get the function adresses
-	for( func = dll->fcts; func && func->name != NULL; func++ )
+	for( i = 0; i < dll->num_fcts; i++ )
 	{
-		if( !( *func->func = Sys_GetProcAddress( dll, func->name )))
+		const dllfunc_t *func = &dll->fcts[i];
+		if( !( *func->func = COM_GetProcAddress( dll->link, func->name )))
 		{
 			Q_snprintf( errorstring, sizeof( errorstring ), "Sys_LoadLibrary: %s missing or invalid function (%s)\n", dll->name, func->name );
 			goto error;
@@ -305,14 +302,6 @@ error:
 	return false;
 }
 
-void* Sys_GetProcAddress( dll_info_t *dll, const char* name )
-{
-	if( !dll || !dll->link ) // invalid desc
-		return NULL;
-
-	return (void *)COM_GetProcAddress( dll->link, name );
-}
-
 qboolean Sys_FreeLibrary( dll_info_t *dll )
 {
 	// invalid desc or alredy freed
@@ -330,6 +319,8 @@ qboolean Sys_FreeLibrary( dll_info_t *dll )
 	COM_FreeLibrary( dll->link );
 	dll->link = NULL;
 
+	ClearExports( dll->fcts, dll->num_fcts );
+
 	return true;
 }
 

engine/common/system.h

@@ -49,7 +49,6 @@ int Sys_CheckParm( const char *parm );
 void Sys_Warn( const char *format, ... ) FORMAT_CHECK( 1 );
 void Sys_Error( const char *error, ... ) FORMAT_CHECK( 1 );
 qboolean Sys_LoadLibrary( dll_info_t *dll );
-void* Sys_GetProcAddress( dll_info_t *dll, const char* name );
 qboolean Sys_FreeLibrary( dll_info_t *dll );
 void Sys_ParseCommandLine( int argc, char **argv );
 void Sys_SetupCrashHandler( void );

public/crtlib.h

@@ -106,6 +106,12 @@ char *COM_ParseFileSafe( char *data, char *token, const int size, unsigned int f
 int matchpattern( const char *in, const char *pattern, qboolean caseinsensitive );
 int matchpattern_with_separator( const char *in, const char *pattern, qboolean caseinsensitive, const char *separators, qboolean wildcard_least_one );
 
+//
+// dllhelpers.c
+//
+void ClearExports( const dllfunc_t *funcs, size_t num_funcs );
+qboolean ValidateExports( const dllfunc_t *funcs, size_t num_funcs );
+
 static inline char Q_toupper( const char in )
 {
 	char	out;

public/dllhelpers.c

@@ -0,0 +1,36 @@
+/*
+dllhelpers.c - dll exports helpers
+Copyright (C) 2024 Alibek Omarov
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+*/
+#include "crtlib.h"
+
+void ClearExports( const dllfunc_t *funcs, size_t num_funcs )
+{
+	size_t i;
+
+	for( i = 0; i < num_funcs; i++ )
+		*(funcs[i].func) = NULL;
+}
+
+qboolean ValidateExports( const dllfunc_t *funcs, size_t num_funcs )
+{
+	size_t i;
+
+	for( i = 0; i < num_funcs; i++ )
+	{
+		if( *(funcs[i].func) == NULL )
+			return false;
+	}
+
+	return true;
+}

ref/gl/gl_opengl.c

@@ -531,8 +531,7 @@ static qboolean GL_CheckExtension( const char *name, const dllfunc_t *funcs, siz
 
 #if !XASH_GL_STATIC
 	// clear exports
-	for( i = 0; i < num_funcs; i++ )
+	ClearExports( funcs, num_funcs );
-		*(funcs[i].func) = NULL;
 
 	for( i = 0; i < num_funcs; i++ )
 	{