dix: unexport and move maxBigRequestSize

* this symbol is a server configuration flag (can be passed via cmdline)
  for limiting the max size of big-requests. there shouldn't be any need
  to use it outside the core X server (in server modules like drivers
  or external extension) - therefore unexport it
* in order to reduce namespace pollution of public (server module API)
  headers, create a new internal header for those tings (more to come)

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1275>

Xext/bigreq.c

@@ -35,6 +35,7 @@ from The Open Group.
 #include "misc.h"
 #include "os.h"
 #include "dixstruct.h"
+#include "dix_priv.h"
 #include "extnsionst.h"
 #include <X11/extensions/bigreqsproto.h>
 #include "opaque.h"

dix/dispatch.c

@@ -105,12 +105,12 @@ Equipment Corporation.
 #include <X11/fonts/fontstruct.h>
 #include <X11/fonts/libxfont2.h>
 #include "dixfontstr.h"
+#include "dix_priv.h"
 #include "gcstruct.h"
 #include "selection.h"
 #include "colormapst.h"
 #include "cursorstr.h"
 #include "scrnintstr.h"
-#include "opaque.h"
 #include "input.h"
 #include "servermd.h"
 #include "extnsionst.h"

dix/dix_priv.h

@@ -0,0 +1,18 @@
+/* SPDX-License-Identifier: MIT OR X11
+ *
+ * Copyright © 2024 Enrico Weigelt, metux IT consult <info@metux.net>
+ */
+#ifndef _XSERVER_DIX_PRIV_H
+#define _XSERVER_DIX_PRIV_H
+
+/* This file holds global DIX settings to be used inside the Xserver,
+ *  but NOT supposed to be accessed directly by external server modules like
+ *  drivers or extension modules. Thus the definitions here are not part of the
+ *  Xserver's module API/ABI.
+ */
+
+/* server setting: maximum size for big requests */
+#define MAX_BIG_REQUEST_SIZE 4194303
+extern long maxBigRequestSize;
+
+#endif /* _XSERVER_DIX_PRIV_H */

dix/globals.c

@@ -56,6 +56,7 @@ SOFTWARE.
 #include "input.h"
 #include "dixfont.h"
 #include "dixstruct.h"
+#include "dix_priv.h"
 #include "os.h"
 
 ScreenInfo screenInfo;

include/opaque.h

@@ -66,7 +66,6 @@ extern _X_EXPORT int limitStackSpace;
 extern _X_EXPORT int limitNoFile;
 #endif
 extern _X_EXPORT Bool defeatAccessControl;
-extern _X_EXPORT long maxBigRequestSize;
 extern _X_EXPORT Bool whiteRoot;
 extern _X_EXPORT Bool bgNoneRoot;
 

include/os.h

@@ -66,9 +66,6 @@ SOFTWARE.
 #ifndef MAX_REQUEST_SIZE
 #define MAX_REQUEST_SIZE 65535
 #endif
-#ifndef MAX_BIG_REQUEST_SIZE
-#define MAX_BIG_REQUEST_SIZE 4194303
-#endif
 
 typedef struct _FontPathRec *FontPathPtr;
 typedef struct _NewClientRec *NewClientPtr;

meson.build

@@ -655,6 +655,7 @@ inc = include_directories(
     'miext/shadow',
     'miext/sync',
     'dbe',
+    'dix',
     'dri3',
     'include',
     'present',

os/io.c

@@ -76,6 +76,7 @@ SOFTWARE.
 #include "osdep.h"
 #include "opaque.h"
 #include "dixstruct.h"
+#include "dix_priv.h"
 #include "misc.h"
 
 CallbackListPtr ReplyCallback;

os/utils.c

@@ -103,10 +103,8 @@ __stdcall unsigned long GetTickCount(void);
 #endif
 #endif
 
-#include "opaque.h"
-
 #include "dixstruct.h"
-
+#include "dix_priv.h"
 #include "xkbsrv.h"
 
 #include "picture.h"