[PATCH v6 1/5] xen/compat: support XEN_HAVE_FOO ifdefs in public interface

[Ian Campbell <ian.campbell@citrix.com>]

This allows us expose or hide interface features on different architectures
without requiring nasty arch-specific ifdeffery.

Preserves any #ifdef with a XEN_HAVE_* symbol name, as well as any #else or

The ifdef symbol becomes COMPAT_HAVE in the compat versions so that
architectures can enable or disable interfaces for compat mode too. (This
actually just fell out of the way the existing stuff works and it didn't seem
worth jumping through hoops to make the name remain XEN_HAVE).

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
Cc: Jan Beulich <jbeulich@suse.com>
---
 xen/tools/compat-build-header.py |    3 +++
 xen/tools/compat-build-source.py |    3 +++
 2 files changed, 6 insertions(+), 0 deletions(-)

diff --git a/xen/tools/compat-build-header.py b/xen/tools/compat-build-header.py
index fba2f37..e296062 100755
--- a/xen/tools/compat-build-header.py
+++ b/xen/tools/compat-build-header.py
@@ -4,6 +4,9 @@ import re,sys
 
 pats = [
  [ r"__InClUdE__(.*)", r"#include\1\n#pragma pack(4)" ],
+ [ r"__IfDeF__ (XEN_HAVE.*)", r"#ifdef \1" ],
+ [ r"__ElSe__", r"#else" ],
+ [ r"__EnDif__", r"#endif" ],
  [ r"\"xen-compat.h\"", r"<public/xen-compat.h>" ],
  [ r"(struct|union|enum)\s+(xen_?)?(\w)", r"\1 compat_\3" ],
  [ r"@KeeP@", r"" ],
diff --git a/xen/tools/compat-build-source.py b/xen/tools/compat-build-source.py
index 3906b71..55206e6 100755
--- a/xen/tools/compat-build-source.py
+++ b/xen/tools/compat-build-source.py
@@ -4,6 +4,9 @@ import re,sys
 
 pats = [
  [ r"^\s*#\s*include\s+", r"__InClUdE__ " ],
+ [ r"^\s*#\s*ifdef (XEN_HAVE.*)\s+", r"__IfDeF__ \1" ],
+ [ r"^\s*#\s*else /\* (XEN_HAVE.*) \*/\s+", r"__ElSe__" ],
+ [ r"^\s*#\s*endif /\* (XEN_HAVE.*) \*/\s+", r"__EnDif__" ],
  [ r"^\s*#\s*define\s+([A-Z_]*_GUEST_HANDLE)", r"#define HIDE_\1" ],
  [ r"^\s*#\s*define\s+([a-z_]*_guest_handle)", r"#define hide_\1" ],
  [ r"XEN_GUEST_HANDLE(_[0-9A-Fa-f]+)?", r"COMPAT_HANDLE" ],
-- 
1.7.2.5