From 213acdb71c9ba679b75bff95de25d126bb659465 Mon Sep 17 00:00:00 2001
From: Simon McVittie <simon.mcvittie@collabora.co.uk>
Date: Tue, 21 Jun 2011 16:19:21 +0100
Subject: [PATCH] Add _DBUS_STATIC_ASSERT (based on GLib's G_STATIC_ASSERT) and
 use it

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=39636
Reviewed-by: Will Thompson <will.thompson@collabora.co.uk>
---
 dbus/dbus-errors.c         | 2 ++
 dbus/dbus-hash.c           | 2 ++
 dbus/dbus-internals.h      | 6 ++++++
 dbus/dbus-string-private.h | 2 ++
 4 files changed, 12 insertions(+)

diff --git a/dbus/dbus-errors.c b/dbus/dbus-errors.c
index 5f27501..db3305b 100644
--- a/dbus/dbus-errors.c
+++ b/dbus/dbus-errors.c
@@ -78,6 +78,8 @@ typedef struct
   
 } DBusRealError;
 
+_DBUS_STATIC_ASSERT (sizeof (DBusRealError) == sizeof (DBusError));
+
 /**
  * Returns a longer message describing an error name.
  * If the error name is unknown, returns the name
diff --git a/dbus/dbus-hash.c b/dbus/dbus-hash.c
index 67ef4ce..b104f32 100644
--- a/dbus/dbus-hash.c
+++ b/dbus/dbus-hash.c
@@ -222,6 +222,8 @@ typedef struct
   int n_entries_on_init;     /**< used to detect table resize since initialization */
 } DBusRealHashIter;
 
+_DBUS_STATIC_ASSERT (sizeof (DBusRealHashIter) == sizeof (DBusHashIter));
+
 static DBusHashEntry* find_direct_function      (DBusHashTable          *table,
                                                  void                   *key,
                                                  dbus_bool_t             create_if_not_found,
diff --git a/dbus/dbus-internals.h b/dbus/dbus-internals.h
index dcef7d7..06e6c16 100644
--- a/dbus/dbus-internals.h
+++ b/dbus/dbus-internals.h
@@ -362,6 +362,12 @@ dbus_bool_t _dbus_read_uuid_file (const DBusString *filename,
 
 dbus_bool_t _dbus_get_local_machine_uuid_encoded (DBusString *uuid_str);
 
+#define _DBUS_PASTE2(a, b) a ## b
+#define _DBUS_PASTE(a, b) _DBUS_PASTE2 (a, b)
+#define _DBUS_STATIC_ASSERT(expr) \
+  typedef struct { char _assertion[(expr) ? 1 : -1]; } \
+  _DBUS_PASTE (_DBUS_STATIC_ASSERT_, __LINE__)
+
 DBUS_END_DECLS
 
 #endif /* DBUS_INTERNALS_H */
diff --git a/dbus/dbus-string-private.h b/dbus/dbus-string-private.h
index 365d89a..b17c2b9 100644
--- a/dbus/dbus-string-private.h
+++ b/dbus/dbus-string-private.h
@@ -24,6 +24,7 @@
 #ifndef DBUS_STRING_PRIVATE_H
 #define DBUS_STRING_PRIVATE_H
 
+#include <dbus/dbus-internals.h>
 #include <dbus/dbus-memory.h>
 #include <dbus/dbus-types.h>
 
@@ -51,6 +52,7 @@ typedef struct
   unsigned int   align_offset : 3; /**< str - align_offset is the actual malloc block */
 } DBusRealString;
 
+_DBUS_STATIC_ASSERT (sizeof (DBusRealString) == sizeof (DBusString));
 
 /**
  * @defgroup DBusStringInternals DBusString implementation details
-- 
2.7.4