From 60c6767337613b0722c9095575938fb7f6f16d10 Mon Sep 17 00:00:00 2001
From: Alibek Omarov <a1ba.omarov@gmail.com>
Date: Mon, 22 Apr 2024 03:39:21 +0300
Subject: [PATCH] filesystem: copy absolute path to library in FS_FindLibrary
 for compatibility

Extend fullPath for longer absolute paths.
---
 engine/common/filesystem_engine.c | 12 ++++++------
 engine/common/library.h           |  3 ++-
 filesystem/filesystem.c           |  9 +++++++--
 filesystem/filesystem.h           |  6 +++---
 4 files changed, 18 insertions(+), 12 deletions(-)

diff --git a/engine/common/filesystem_engine.c b/engine/common/filesystem_engine.c
index 2b1e341e..79ba2398 100644
--- a/engine/common/filesystem_engine.c
+++ b/engine/common/filesystem_engine.c
@@ -89,32 +89,32 @@ qboolean FS_LoadProgs( void )
 
 	if( !fs_hInstance )
 	{
-		Host_Error( "FS_LoadProgs: can't load filesystem library %s: %s\n", name, COM_GetLibraryError() );
+		Host_Error( "%s: can't load filesystem library %s: %s\n", __func__, name, COM_GetLibraryError() );
 		return false;
 	}
 
 	if( !( GetFSAPI = (FSAPI)COM_GetProcAddress( fs_hInstance, GET_FS_API )))
 	{
 		FS_UnloadProgs();
-		Host_Error( "FS_LoadProgs: can't find GetFSAPI entry point in %s\n", name );
+		Host_Error( "%s: can't find GetFSAPI entry point in %s\n", __func__, name );
 		return false;
 	}
 
-	if( !GetFSAPI( FS_API_VERSION, &g_fsapi, &FI, &fs_memfuncs ))
+	if( GetFSAPI( FS_API_VERSION, &g_fsapi, &FI, &fs_memfuncs ) != FS_API_VERSION )
 	{
 		FS_UnloadProgs();
-		Host_Error( "FS_LoadProgs: can't initialize filesystem API: wrong version\n" );
+		Host_Error( "%s: can't initialize filesystem API: wrong version\n", __func__ );
 		return false;
 	}
 
 	if( !( fs_pfnCreateInterface = (pfnCreateInterface_t)COM_GetProcAddress( fs_hInstance, "CreateInterface" )))
 	{
 		FS_UnloadProgs();
-		Host_Error( "FS_LoadProgs: can't find CreateInterface entry point in %s\n", name );
+		Host_Error( "%s: can't find CreateInterface entry point in %s\n", __func__, name );
 		return false;
 	}
 
-	Con_DPrintf( "FS_LoadProgs: filesystem_stdio successfully loaded\n" );
+	Con_DPrintf( "%s: filesystem_stdio successfully loaded\n", __func__ );
 
 	return true;
 }
diff --git a/engine/common/library.h b/engine/common/library.h
index 10524249..65572ad0 100644
--- a/engine/common/library.h
+++ b/engine/common/library.h
@@ -24,7 +24,8 @@ typedef struct dll_user_s
 	qboolean	custom_loader;		// a bit who indicated loader type
 	qboolean	encrypted;		// dll is crypted (some client.dll in HL, CS etc)
 	char	dllName[32];		// for debug messages
-	string	fullPath, shortPath;	// actual dll paths
+	char fullPath[2048];
+	string shortPath;	// actual dll paths
 
 	// ordinals stuff, valid only on Win32
 	word	*ordinals;
diff --git a/filesystem/filesystem.c b/filesystem/filesystem.c
index eab49eb7..18d92839 100644
--- a/filesystem/filesystem.c
+++ b/filesystem/filesystem.c
@@ -1363,8 +1363,13 @@ static qboolean FS_FindLibrary( const char *dllname, qboolean directpath, fs_dll
 
 	if( index >= 0 && !dllInfo->encrypted && search )
 	{
-		Q_snprintf( dllInfo->fullPath, sizeof( dllInfo->fullPath ),
-			"%s%s", search->filename, dllInfo->shortPath );
+		// gamedll might resolve it's own path using dladdr()
+		// combine it with engine returned path to gamedir
+		// it might lead to double gamedir like this
+		// - valve/valve/dlls/hl.so
+		// instead of expected
+		// - valve/dlls/hl.so
+		Q_snprintf( dllInfo->fullPath, sizeof( dllInfo->fullPath ), "%s/%s%s", fs_rootdir, search->filename, dllInfo->shortPath );
 		dllInfo->custom_loader = false;	// we can loading from disk and use normal debugging
 	}
 	else
diff --git a/filesystem/filesystem.h b/filesystem/filesystem.h
index 716fb4d6..f6d3e85d 100644
--- a/filesystem/filesystem.h
+++ b/filesystem/filesystem.h
@@ -31,7 +31,7 @@ extern "C"
 {
 #endif // __cplusplus
 
-#define FS_API_VERSION 2 // not stable yet!
+#define FS_API_VERSION 3 // not stable yet!
 #define FS_API_CREATEINTERFACE_TAG   "XashFileSystem002" // follow FS_API_VERSION!!!
 #define FILESYSTEM_INTERFACE_VERSION "VFileSystem009" // never change this!
 
@@ -121,8 +121,8 @@ typedef enum
 
 typedef struct fs_dllinfo_t
 {
-	string fullPath;
-	string shortPath;
+	char fullPath[2048]; // absolute disk path
+	string shortPath; // vfs path
 	qboolean encrypted;
 	qboolean custom_loader;
 } fs_dllinfo_t;