require POLKIT_AGENT_I_KNOW_API_IS_SUBJECT_TO_CHANGE to be defined

Also use @stability in the docs to indicate that the interface is
currently subject to change.

src/polkitagent/Makefile.am

@@ -12,6 +12,7 @@ INCLUDES =                                                      \
         -DPACKAGE_LIB_DIR=\""$(libdir)"\"                       \
         -D_POSIX_PTHREAD_SEMANTICS                              \
         -D_REENTRANT                                            \
+	-DPOLKIT_AGENT_COMPILATION				\
 	-DEGG_DBUS_I_KNOW_API_IS_SUBJECT_TO_CHANGE		\
         $(NULL)
 
@@ -60,7 +61,6 @@ libpolkit_agent_1_la_SOURCES =                                   			\
         $(NULL)
 
 libpolkit_agent_1_la_CFLAGS =                                        	\
-        -D_POLKIT_AGENT_COMPILATION                                  	\
         $(GLIB_CFLAGS)							\
         $(EGG_DBUS_CFLAGS)						\
         $(NULL)

src/polkitagent/polkitagent.h

@@ -22,9 +22,14 @@
 #ifndef __POLKIT_AGENT_H
 #define __POLKIT_AGENT_H
 
-#define _POLKIT_AGENT_INSIDE_POLKIT_AGENT_H 1
+#if !defined (POLKIT_AGENT_I_KNOW_API_IS_SUBJECT_TO_CHANGE) && !defined (POLKIT_AGENT_COMPILATION)
+#error "libpolkitagent is unstable API and subject to change. You must define POLKIT_AGENT_I_KNOW_API_IS_SUBJECT_TO_CHANGE to acknowledge this."
+#endif
+
+#define POLKIT_AGENT_INSIDE_POLKIT_AGENT_H 1
+#include <polkitagent/polkitagenttypes.h>
 #include <polkitagent/polkitagentlistener.h>
 #include <polkitagent/polkitagentsession.h>
-#undef _POLKIT_AGENT_INSIDE_POLKIT_AGENT_H
+#undef POLKIT_AGENT_INSIDE_POLKIT_AGENT_H
 
 #endif /* __POLKIT_AGENT_H */

src/polkitagent/polkitagentlistener.c

@@ -30,6 +30,7 @@
  * SECTION:polkitagentlistener
  * @title: PolkitAgentListener
  * @short_description: Abstract base class for Authentication Agents
+ * @stability: Unstable
  *
  * #PolkitAgentListener is an abstract base class used for implementing authentication
  * agents. To implement an authentication agent, simply subclass #PolkitAgentListener and

src/polkitagent/polkitagentlistener.h

@@ -19,6 +19,10 @@
  * Author: David Zeuthen <davidz@redhat.com>
  */
 
+#if !defined(POLKIT_AGENT_INSIDE_POLKIT_AGENT_H) && !defined (POLKIT_AGENT_COMPILATION)
+#error "Only <polkitagent/polkitagent.h> can be included directly, this file may disappear or change contents"
+#endif
+
 #ifndef __POLKIT_AGENT_LISTENER_H
 #define __POLKIT_AGENT_LISTENER_H
 

src/polkitagent/polkitagentsession.c

@@ -23,6 +23,7 @@
  * SECTION:polkitagentsession
  * @title: PolkitAgentSession
  * @short_description: Authentication Session
+ * @stability: Unstable
  *
  * The #PolkitAgentSession class is an abstraction used for interacting with the
  * native authentication system (for example PAM) for obtaining authorizations.

src/polkitagent/polkitagentsession.h

@@ -19,6 +19,10 @@
  * Author: David Zeuthen <davidz@redhat.com>
  */
 
+#if !defined(POLKIT_AGENT_INSIDE_POLKIT_AGENT_H) && !defined (POLKIT_AGENT_COMPILATION)
+#error "Only <polkitagent/polkitagent.h> can be included directly, this file may disappear or change contents"
+#endif
+
 #ifndef __POLKIT_AGENT_SESSION_H
 #define __POLKIT_AGENT_SESSION_H
 

src/polkitagent/polkitagenttypes.h

@@ -19,6 +19,10 @@
  * Author: David Zeuthen <davidz@redhat.com>
  */
 
+#if !defined(POLKIT_AGENT_INSIDE_POLKIT_AGENT_H) && !defined (POLKIT_AGENT_COMPILATION)
+#error "Only <polkitagent/polkitagent.h> can be included directly, this file may disappear or change contents"
+#endif
+
 #ifndef __POLKIT_AGENT_TYPES_H
 #define __POLKIT_AGENT_TYPES_H