diff include/freeDiameter/libfdproto.h @ 658:f198d16fa7f4

Initial commit for 1.1.0: * Restructuring: * libfreeDiameter: - renamed folder & binary into libfdproto - renamed libfD.h into fdproto-internal.h - removed signals management (replaced by triggers in libfdcore) * freeDiameter split into: - libfdcore (most contents) - renamed fD.h into fdcore-internal.h - added core.c for framework init/shutdown. - new triggers mechanism in events.c. - freeDiameterd (main, command line parsing, signals management) * tests: - now in top-level directory tests. * other changes: - fd_dict_new now returns 0 on duplicate identical entries. - fixes in dict_legacy_xml - fixes in some dictionaries - moved FD_DEFAULT_CONF_FILENAME definition to freeDiameter-host.h
author Sebastien Decugis <sdecugis@nict.go.jp>
date Fri, 14 Jan 2011 15:15:23 +0900
parents include/freeDiameter/libfreeDiameter.h@34373acfbc6a
children 026802543f57
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/include/freeDiameter/libfdproto.h	Fri Jan 14 15:15:23 2011 +0900
@@ -0,0 +1,2794 @@
+/*********************************************************************************************************
+* Software License Agreement (BSD License)                                                               *
+* Author: Sebastien Decugis <sdecugis@nict.go.jp>							 *
+*													 *
+* Copyright (c) 2011, WIDE Project and NICT								 *
+* All rights reserved.											 *
+* 													 *
+* Redistribution and use of this software in source and binary forms, with or without modification, are  *
+* permitted provided that the following conditions are met:						 *
+* 													 *
+* * Redistributions of source code must retain the above 						 *
+*   copyright notice, this list of conditions and the 							 *
+*   following disclaimer.										 *
+*    													 *
+* * Redistributions in binary form must reproduce the above 						 *
+*   copyright notice, this list of conditions and the 							 *
+*   following disclaimer in the documentation and/or other						 *
+*   materials provided with the distribution.								 *
+* 													 *
+* * Neither the name of the WIDE Project or NICT nor the 						 *
+*   names of its contributors may be used to endorse or 						 *
+*   promote products derived from this software without 						 *
+*   specific prior written permission of WIDE Project and 						 *
+*   NICT.												 *
+* 													 *
+* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED *
+* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A *
+* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR *
+* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 	 *
+* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 	 *
+* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR *
+* TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY S_OUT OF THE USE OF THIS SOFTWARE, EVEN IF   *
+* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.								 *
+*********************************************************************************************************/
+
+/* This file contains the definitions of functions and types used by the libfreeDiameter library.
+ *
+ * This library is meant to be used by both the freeDiameter daemon and its extensions.
+ * It provides the tools to manipulate Diameter messages and related data.
+ * This file should always be included as #include <freeDiameter/libfreeDiameter.h>
+ *
+ * If any change is made to this file, you must increment the FD_PROJECT_VERSION_API version.
+ *
+ * The file contains the following parts:
+ *	DEBUG
+ *	MACROS
+ *	THREADS
+ *	LISTS
+ *	DICTIONARY
+ *	SESSIONS
+ *	MESSAGES
+ *	DISPATCH
+ *	QUEUES
+ */
+
+#ifndef _LIBFDPROTO_H
+#define _LIBFDPROTO_H
+
+#ifndef FD_IS_CONFIG
+#error "You must include 'freeDiameter-host.h' before this file."
+#endif /* FD_IS_CONFIG */
+
+#include <pthread.h>
+#include <sched.h>
+#include <string.h>
+#include <assert.h>
+#include <errno.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <sys/socket.h>
+#include <netdb.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#ifdef DEBUG
+#include <libgen.h>	/* for basename if --dbg_file is specified */
+#endif /* DEBUG */
+
+/*============================================================*/
+/*                          INIT                              */
+/*============================================================*/
+
+/* This function must be called first, before any call to another library function */
+int fd_libproto_init(void); /* note if you are using libfdcore, it handles this already */
+
+/* Call this one when the application terminates, to destroy internal threads */
+void fd_libproto_fini(void);
+
+
+/*============================================================*/
+/*                          DEBUG                             */
+/*============================================================*/
+
+
+/*
+ * FUNCTION:	fd_log_debug
+ *
+ * PARAMETERS:
+ *  format 	: Same format string as in the printf function
+ *  ...		: Same list as printf
+ *
+ * DESCRIPTION: 
+ *  Log internal information for use of developpers only.
+ * The format and arguments may contain UTF-8 encoded data. The
+ * output medium (file or console) is expected to support this encoding.
+ *
+ * This function assumes that a global mutex called "fd_log_lock" exists
+ * in the address space of the current process.
+ *
+ * RETURN VALUE:
+ *  None.
+ */
+void fd_log_debug ( const char * format, ... );
+extern pthread_mutex_t	fd_log_lock;
+extern char * fd_debug_one_function;
+extern char * fd_debug_one_file;
+
+/*
+ * FUNCTION:	fd_log_threadname
+ *
+ * PARAMETERS:
+ *  name 	: \0-terminated string containing a name to identify the current thread.
+ *
+ * DESCRIPTION: 
+ *  Name the current thread, useful for debugging multi-threaded problems.
+ *
+ * This function assumes that a global thread-specific key called "fd_log_thname" exists
+ * in the address space of the current process.
+ *
+ * RETURN VALUE:
+ *  None.
+ */
+void fd_log_threadname ( char * name );
+extern pthread_key_t	fd_log_thname;
+
+/*
+ * FUNCTION:	fd_log_time
+ *
+ * PARAMETERS:
+ *  ts	 	: The timestamp to log, or NULL for "now"
+ *  buf 	: An array where the time must be stored
+ *  len		: size of the buffer
+ *
+ * DESCRIPTION: 
+ *  Writes the timestamp (in human readable format) in a buffer. 
+ *
+ * RETURN VALUE:
+ *  pointer to buf.
+ */
+char * fd_log_time ( struct timespec * ts, char * buf, size_t len );
+
+
+/*============================================================*/
+/*                    DEBUG MACROS                            */
+/*============================================================*/
+
+#ifndef ASSERT
+#define ASSERT(x) assert(x)
+#endif /* ASSERT */
+
+/* levels definitions */
+#define NONE 0	/* Display no debug message */
+#define INFO 1	/* Display errors only */
+#define FULL 2  /* Display additional information to follow code execution */
+#define ANNOYING 4 /* Very verbose, for example in loops */
+#define FCTS 6  /* Display entry parameters of most functions */
+#define CALL 9  /* Display calls to most functions (with CHECK macros) */
+
+/* Default level is INFO */
+#ifndef TRACE_LEVEL 
+#define TRACE_LEVEL INFO
+#endif /* TRACE_LEVEL */
+
+/* The level of the file being compiled. */
+static int local_debug_level = TRACE_LEVEL;
+
+/* A global level, changed by configuration or cmd line for example. default is 0. */
+extern int fd_g_debug_lvl;
+
+/* Some portability code to get nice function name in __PRETTY_FUNCTION__ */
+#if __STDC_VERSION__ < 199901L
+# if __GNUC__ >= 2
+#  define __func__ __FUNCTION__
+# else /* __GNUC__ >= 2 */
+#  define __func__ "<unknown>"
+# endif /* __GNUC__ >= 2 */
+#endif /* __STDC_VERSION__ < 199901L */
+#ifndef __PRETTY_FUNCTION__
+#define __PRETTY_FUNCTION__ __func__
+#endif /* __PRETTY_FUNCTION__ */
+
+/* A version of __FILE__ without the full path */
+static char * file_bname = NULL;
+#define __STRIPPED_FILE__	(file_bname ?: (file_bname = basename((char *)__FILE__)))
+
+
+/* Boolean for tracing at a certain level */
+#ifdef DEBUG
+#define TRACE_BOOL(_level_) ( ((_level_) <= local_debug_level + fd_g_debug_lvl) 					\
+				|| (fd_debug_one_function && !strcmp(fd_debug_one_function, __PRETTY_FUNCTION__)) 	\
+				|| (fd_debug_one_file && !strcmp(fd_debug_one_file, __STRIPPED_FILE__) ) )
+#else /* DEBUG */
+#define TRACE_BOOL(_level_) ((_level_) <= local_debug_level + fd_g_debug_lvl)
+#endif /* DEBUG */
+
+
+/*************
+ The general debug macro, each call results in two lines of debug messages (change the macro for more compact output) 
+ *************/
+#ifdef DEBUG
+/* In DEBUG mode, we add (a lot of) meta-information along each trace. This makes multi-threading problems easier to debug. */
+#define TRACE_DEBUG(level,format,args... ) {											\
+	if ( TRACE_BOOL(level) ) {												\
+		char __buf[25];													\
+		const char * __thn = ((char *)pthread_getspecific(fd_log_thname) ?: "unnamed");					\
+		fd_log_debug("\t | tid:%-20s\t%s\tin %s@%s:%d\n"								\
+			  "\t%s|%*s" format "\n",  										\
+					__thn, fd_log_time(NULL, __buf, sizeof(__buf)), __PRETTY_FUNCTION__, __FILE__, __LINE__,\
+					(level < FULL)?"@":" ",level, "", ## args); 						\
+	}															\
+}
+#else /* DEBUG */
+/* Do not print thread, function, ... only the message itself in this case, unless the debug level is set > FULL. */
+#define TRACE_DEBUG(level,format,args... ) {												\
+	if ( TRACE_BOOL(level) ) {													\
+		if (fd_g_debug_lvl > FULL) {												\
+			char __buf[25];													\
+			const char * __thn = ((char *)pthread_getspecific(fd_log_thname) ?: "unnamed");					\
+			fd_log_debug("\t | tid:%-20s\t%s\tin %s@%s:%d\n"								\
+				  "\t%s|%*s" format "\n",  										\
+						__thn, fd_log_time(NULL, __buf, sizeof(__buf)), __PRETTY_FUNCTION__, __FILE__, __LINE__,\
+						(level < FULL)?"@":" ",level, "", ## args); 						\
+		} else {														\
+			fd_log_debug(format "\n", ## args); 										\
+		}															\
+	}																\
+}
+#endif /* DEBUG */
+
+/*************
+ Derivatives from this macro 
+ ************/
+/* Helper for function entry -- for very detailed trace of the execution */
+#define TRACE_ENTRY(_format,_args... ) \
+	TRACE_DEBUG(FCTS, "[enter] %s(" _format ") {" #_args "}", __PRETTY_FUNCTION__, ##_args );
+
+/* Helper for debugging by adding traces -- for debuging a specific location of the code */
+#define TRACE_HERE()	\
+	TRACE_DEBUG(NONE, " -- debug checkpoint %d -- ", fd_breakhere());
+int fd_breakhere(void);
+
+/* Helper for tracing the CHECK_* macros bellow -- very very verbose code execution! */
+#define TRACE_DEBUG_ALL( str ) 	\
+	TRACE_DEBUG(CALL, str );
+
+/* For development only, to keep track of TODO locations in the code */
+#ifndef ERRORS_ON_TODO
+#define TODO( _msg, _args... ) \
+	TRACE_DEBUG(NONE, "TODO: " _msg , ##_args);
+#else /* ERRORS_ON_TODO */
+#define TODO( _msg, _args... ) \
+	"TODO" = _msg ## _args; /* just a stupid compilation error to spot the todo */
+#endif /* ERRORS_ON_TODO */
+
+/* Trace a binary buffer content */
+#define TRACE_DEBUG_BUFFER(level, prefix, buf, bufsz, suffix ) {								\
+	if ( TRACE_BOOL(level) ) {												\
+		char __ts[25];													\
+		int __i;													\
+		size_t __sz = (size_t)(bufsz);											\
+		uint8_t * __buf = (uint8_t *)(buf);										\
+		char * __thn = ((char *)pthread_getspecific(fd_log_thname) ?: "unnamed");					\
+		fd_log_debug("\t | tid:%-20s\t%s\tin %s@%s:%d\n"								\
+			  "\t%s|%*s" prefix ,  											\
+					__thn, fd_log_time(NULL, __ts, sizeof(__ts)), __PRETTY_FUNCTION__, __FILE__, __LINE__,	\
+					(level < FULL)?"@":" ",level, ""); 							\
+		for (__i = 0; __i < __sz; __i++) {										\
+			fd_log_debug("%02.2hhx", __buf[__i]);									\
+		}														\
+		fd_log_debug(suffix "\n");											\
+	}															\
+}
+
+/* Some aliases to socket addresses structures */
+#define sSS	struct sockaddr_storage
+#define sSA	struct sockaddr
+#define sSA4	struct sockaddr_in
+#define sSA6	struct sockaddr_in6
+
+/* The sockaddr length of a sSS structure */
+#define sSAlen( _sa_ )	\
+	( (socklen_t) ( (((sSA *)_sa_)->sa_family == AF_INET) ? (sizeof(sSA4)) :		\
+				((((sSA *)_sa_)->sa_family == AF_INET6) ? (sizeof(sSA6)) :	\
+					0 ) ) )
+
+/* Dump one sockaddr Node information */
+#define sSA_DUMP_NODE( sa, flag ) {				\
+	sSA * __sa = (sSA *)(sa);				\
+	char __addrbuf[INET6_ADDRSTRLEN];			\
+	if (__sa) {						\
+	  int __rc = getnameinfo(__sa, 				\
+	  		sSAlen(__sa),				\
+			__addrbuf,				\
+			sizeof(__addrbuf),			\
+			NULL,					\
+			0,					\
+			flag);					\
+	  if (__rc)						\
+	  	fd_log_debug("%s", (char *)gai_strerror(__rc));	\
+	  else							\
+	  	fd_log_debug("%s", &__addrbuf[0]);		\
+	} else {						\
+		fd_log_debug("(NULL / ANY)");			\
+	}							\
+}
+/* Same but with the port (service) also */
+#define sSA_DUMP_NODE_SERV( sa, flag ) {				\
+	sSA * __sa = (sSA *)(sa);					\
+	char __addrbuf[INET6_ADDRSTRLEN];				\
+	char __servbuf[32];						\
+	if (__sa) {							\
+	  int __rc = getnameinfo(__sa, 					\
+	  		sSAlen(__sa),					\
+			__addrbuf,					\
+			sizeof(__addrbuf),				\
+			__servbuf,					\
+			sizeof(__servbuf),				\
+			flag);						\
+	  if (__rc)							\
+	  	fd_log_debug("%s", (char *)gai_strerror(__rc));		\
+	  else								\
+	  	fd_log_debug("[%s]:%s", &__addrbuf[0],&__servbuf[0]);	\
+	} else {							\
+		fd_log_debug("(NULL / ANY)");				\
+	}								\
+}
+
+/* Inside a debug trace */
+#define TRACE_DEBUG_sSA(level, prefix, sa, flags, suffix ) {										\
+	if ( TRACE_BOOL(level) ) {												\
+		char __buf[25];													\
+		char * __thn = ((char *)pthread_getspecific(fd_log_thname) ?: "unnamed");					\
+		fd_log_debug("\t | tid:%-20s\t%s\tin %s@%s:%d\n"								\
+			  "\t%s|%*s" prefix ,  											\
+					__thn, fd_log_time(NULL, __buf, sizeof(__buf)), __PRETTY_FUNCTION__, __FILE__, __LINE__,\
+					(level < FULL)?"@":" ",level, ""); 							\
+		sSA_DUMP_NODE_SERV( sa, flags );										\
+		fd_log_debug(suffix "\n");											\
+	}															\
+}
+
+/* Report an error */
+#define TRACE_DEBUG_ERROR(format,args... ) \
+	TRACE_DEBUG(NONE, format, ##args)
+
+/******************
+ Optimized code: remove all debugging code
+ **/
+#ifdef STRIP_DEBUG_CODE
+#undef TRACE_DEBUG
+#undef TRACE_BOOL
+#undef TRACE_DEBUG_sSA
+#undef TRACE_DEBUG_BUFFER
+#undef TRACE_DEBUG_ERROR
+#define TRACE_DEBUG(level,format,args... )
+#define TRACE_BOOL(_level_) (0)
+#define TRACE_DEBUG_BUFFER(level, prefix, buf, bufsz, suffix )
+#define TRACE_DEBUG_sSA(level, prefix, sa, flags, suffix )
+#define TRACE_DEBUG_ERROR(format,args... ) {	\
+	fd_log_debug(format "\n", ## args); 	\
+}
+#endif /* STRIP_DEBUG_CODE */
+
+
+/*============================================================*/
+/*                  ERROR CHECKING MACRO                      */
+/*============================================================*/
+
+/* Macros to check a return value and branch out in case of error.
+ * These macro should be used only when errors are improbable, not for expected errors.
+ */
+
+/* Check the return value of a system function and execute fallback in case of error */
+#define CHECK_SYS_DO( __call__, __fallback__  ) { 					\
+	int __ret__;									\
+	TRACE_DEBUG_ALL( "Check SYS: " #__call__ );					\
+	__ret__ = (__call__);								\
+	if (__ret__ < 0) {								\
+		int __err__ = errno;	/* We may handle EINTR here */			\
+		TRACE_DEBUG_ERROR("ERROR: in '" #__call__ "' :\t%s", strerror(__err__));\
+		__fallback__;								\
+	}										\
+}
+/* Check the return value of a system function, return error code on error */
+#define CHECK_SYS( __call__  ) { 							\
+	int __ret__;									\
+	TRACE_DEBUG_ALL( "Check SYS: " #__call__ );					\
+	__ret__ = (__call__);								\
+	if (__ret__ < 0) {								\
+		int __err__ = errno;	/* We may handle EINTR here */			\
+		TRACE_DEBUG_ERROR("ERROR: in '" #__call__ "' :\t%s", strerror(__err__));\
+		return __err__;								\
+	}										\
+}
+
+/* Check the return value of a POSIX function and execute fallback in case of error or special value */
+#define CHECK_POSIX_DO2( __call__, __speval__, __fallback1__, __fallback2__ ) {			\
+	int __ret__;										\
+	TRACE_DEBUG_ALL( "Check POSIX: " #__call__ );						\
+	__ret__ = (__call__);									\
+	if (__ret__ != 0) {									\
+		if (__ret__ == (__speval__)) {							\
+			__fallback1__;								\
+		} else {									\
+			TRACE_DEBUG_ERROR("ERROR: in '" #__call__ "':\t%s", strerror(__ret__));	\
+			__fallback2__;								\
+		}										\
+	}											\
+}
+
+/* Check the return value of a POSIX function and execute fallback in case of error */
+#define CHECK_POSIX_DO( __call__, __fallback__ ) 					\
+	CHECK_POSIX_DO2( (__call__), 0, , __fallback__ );
+
+/* Check the return value of a POSIX function and return it if error */
+#define CHECK_POSIX( __call__ ) { 							\
+	int __v__;									\
+	CHECK_POSIX_DO( __v__ = (__call__), return __v__ );				\
+}
+
+/* Check that a memory allocator did not return NULL, otherwise log an error and execute fallback */
+#define CHECK_MALLOC_DO( __call__, __fallback__ ) { 					\
+	void *  __ret__;								\
+	TRACE_DEBUG_ALL( "Check MALLOC: " #__call__ );					\
+	__ret__ = (void *)( __call__ );							\
+	if (__ret__ == NULL) {								\
+		int __err__ = errno;							\
+		TRACE_DEBUG_ERROR("ERROR: in '" #__call__ "':\t%s", strerror(__err__));	\
+		__fallback__;								\
+	}										\
+}
+
+/* Check that a memory allocator did not return NULL, otherwise return ENOMEM */
+#define CHECK_MALLOC( __call__ )							\
+	CHECK_MALLOC_DO( __call__, return ENOMEM );
+
+
+/* Check parameters at function entry, execute fallback on error */
+#define CHECK_PARAMS_DO( __bool__, __fallback__ )						\
+	TRACE_DEBUG_ALL( "Check PARAMS: " #__bool__ );						\
+	if ( ! (__bool__) ) {									\
+		TRACE_DEBUG_ERROR("Warning: Invalid parameter received in '" #__bool__ "'");	\
+		__fallback__;									\
+	}
+/* Check parameters at function entry, return EINVAL if the boolean is false (similar to assert) */
+#define CHECK_PARAMS( __bool__ )							\
+	CHECK_PARAMS_DO( __bool__, return EINVAL );
+
+/* Check the return value of an internal function, log and propagate */
+#define CHECK_FCT_DO( __call__, __fallback__ ) {					\
+	int __ret__;									\
+	TRACE_DEBUG_ALL( "Check FCT: " #__call__ );					\
+	__ret__ = (__call__);								\
+	if (__ret__ != 0) {								\
+		TRACE_DEBUG_ERROR("ERROR: in '" #__call__ "':\t%s", strerror(__ret__));	\
+		__fallback__;								\
+	}										\
+}
+/* Check the return value of a function call, return any error code */
+#define CHECK_FCT( __call__ ) {								\
+	int __v__;									\
+	CHECK_FCT_DO( __v__ = (__call__), return __v__ );				\
+}
+
+
+
+/*============================================================*/
+/*                  OTHER MACROS                              */
+/*============================================================*/
+
+
+/* helper macros (pre-processor hacks to allow macro arguments) */
+#define __tostr( arg )  #arg
+#define _stringize( arg ) __tostr( arg )
+#define __agr( arg1, arg2 ) arg1 ## arg2
+#define _aggregate( arg1, arg2 ) __agr( arg1, arg2 )
+
+
+/* A l4 protocol name (TCP / SCTP) */
+#ifdef DISABLE_SCTP
+#define IPPROTO_NAME( _proto )					\
+	(((_proto) == IPPROTO_TCP) ? "TCP" :			\
+			"Unknown")
+#else /* DISABLE_SCTP */
+#define IPPROTO_NAME( _proto )					\
+	( ((_proto) == IPPROTO_TCP) ? "TCP" :			\
+		(((_proto) == IPPROTO_SCTP) ? "SCTP" :		\
+			"Unknown"))
+#endif /* DISABLE_SCTP */
+
+/* Define the value of IP loopback address */
+#ifndef INADDR_LOOPBACK 
+#define INADDR_LOOPBACK	inet_addr("127.0.0.1")
+#endif /* INADDR_LOOPBACK */
+
+#ifndef INADDR_BROADCAST
+#define	INADDR_BROADCAST	((in_addr_t) 0xffffffff)
+#endif /* INADDR_BROADCAST */
+
+/* An IP equivalent to IN6_IS_ADDR_LOOPBACK */
+#ifndef IN_IS_ADDR_LOOPBACK
+#define IN_IS_ADDR_LOOPBACK(a) \
+  ((((long int) (a)->s_addr) & ntohl(0xff000000)) == ntohl(0x7f000000))
+#endif /* IN_IS_ADDR_LOOPBACK */
+
+/* An IP equivalent to IN6_IS_ADDR_UNSPECIFIED */
+#ifndef IN_IS_ADDR_UNSPECIFIED
+#define IN_IS_ADDR_UNSPECIFIED(a) \
+  (((long int) (a)->s_addr) == 0x00000000)
+#endif /* IN_IS_ADDR_UNSPECIFIED */
+
+/* create a V4MAPPED address */
+#define IN6_ADDR_V4MAP( a6, a4 ) {			\
+	((uint32_t *)(a6))[0] = 0;			\
+	((uint32_t *)(a6))[1] = 0;			\
+	((uint32_t *)(a6))[2] = htonl(0xffff);		\
+	((uint32_t *)(a6))[3] = (uint32_t)(a4);		\
+}
+
+/* Retrieve a v4 value from V4MAPPED address ( takes a s6_addr as param) */
+#define IN6_ADDR_V4UNMAP( a6 ) 				\
+	(((in_addr_t *)(a6))[3])
+
+
+/* We provide macros to convert 64 bit values to and from network byte-order, on systems where it is not already provided. */
+#ifndef HAVE_NTOHLL	/* Defined by the cmake step, if the ntohll symbol is defined on the system */
+# if HOST_BIG_ENDIAN
+    /* In big-endian systems, we don't have to change the values, since the order is the same as network */
+#   define ntohll(x) (x)
+#   define htonll(x) (x)
+# else /* HOST_BIG_ENDIAN */
+    /* For these systems, we must reverse the bytes. Use ntohl and htonl on sub-32 blocs, and inverse these blocs. */
+#   define ntohll(x) (typeof (x))( (((uint64_t)ntohl( (uint32_t)(x))) << 32 ) | ((uint64_t) ntohl( ((uint64_t)(x)) >> 32 ))) 
+#   define htonll(x) (typeof (x))( (((uint64_t)htonl( (uint32_t)(x))) << 32 ) | ((uint64_t) htonl( ((uint64_t)(x)) >> 32 ))) 
+# endif /* HOST_BIG_ENDIAN */
+#endif /* HAVE_NTOHLL */
+
+/* This macro will give the next multiple of 4 for an integer (used for padding sizes of AVP). */
+#define PAD4(_x) ((_x) + ( (4 - (_x)) & 3 ) )
+
+/* Useful to display any value as (safe) ASCII (will garbage UTF-8 output...) */
+#define ASCII(_c) ( ((_c < 32) || (_c > 127)) ? ( _c ? '?' : ' ' ) : _c )
+
+/* Compare timespec structures */
+#define TS_IS_INFERIOR( ts1, ts2 ) 		\
+	(    ((ts1)->tv_sec  < (ts2)->tv_sec ) 	\
+	  || (((ts1)->tv_sec  == (ts2)->tv_sec ) && ((ts1)->tv_nsec < (ts2)->tv_nsec) ))
+
+/* This gives a good size for buffered reads */
+#ifndef BUFSIZ
+#define BUFSIZ 96
+#endif /* BUFSIZ */
+
+
+
+/*============================================================*/
+/*                          THREADS                           */
+/*============================================================*/
+
+/* Terminate a thread */
+static __inline__ int fd_thr_term(pthread_t * th)
+{
+	void * th_ret = NULL;
+	
+	CHECK_PARAMS(th);
+	
+	/* Test if it was already terminated */
+	if (*th == (pthread_t)NULL)
+		return 0;
+	
+	/* Cancel the thread if it is still running - ignore error if it was already terminated */
+	(void) pthread_cancel(*th);
+	
+	/* Then join the thread */
+	CHECK_POSIX( pthread_join(*th, &th_ret) );
+	
+	if (th_ret == PTHREAD_CANCELED) {
+		TRACE_DEBUG(ANNOYING, "The thread %p was canceled", *th);
+	} else {
+		TRACE_DEBUG(CALL, "The thread %p returned %x", *th, th_ret);
+	}
+	
+	/* Clean the location */
+	*th = (pthread_t)NULL;
+	
+	return 0;
+}
+
+/* Force flushing the cache of a CPU before reading a shared memory area (use only for atomic reads such as int and void*) */
+extern pthread_mutex_t fd_cpu_mtx_dummy; /* only for the macro bellow, so that we have reasonably fresh pir_state value when needed */
+#define fd_cpu_flush_cache() {				\
+	(void)pthread_mutex_lock(&fd_cpu_mtx_dummy);	\
+	(void)pthread_mutex_unlock(&fd_cpu_mtx_dummy);	\
+}
+
+
+/*************
+ Cancelation cleanup handlers for common objects 
+ *************/
+static __inline__ void fd_cleanup_mutex( void * mutex )
+{
+	CHECK_POSIX_DO( pthread_mutex_unlock((pthread_mutex_t *)mutex), /* */);
+}
+		
+static __inline__ void fd_cleanup_rwlock( void * rwlock )
+{
+	CHECK_POSIX_DO( pthread_rwlock_unlock((pthread_rwlock_t *)rwlock), /* */);
+}
+
+static __inline__ void fd_cleanup_buffer( void * buffer )
+{
+	free(buffer);
+}
+static __inline__ void fd_cleanup_socket(void * sockptr)
+{
+	if (sockptr && (*(int *)sockptr > 0)) {
+		CHECK_SYS_DO( close(*(int *)sockptr), /* ignore */ );
+		*(int *)sockptr = -1;
+	}
+}
+
+
+/*============================================================*/
+/*                          LISTS                             */
+/*============================================================*/
+
+/* The following structure represents a chained list element  */
+struct fd_list {
+	struct fd_list 	*next; /* next element in the list */
+	struct fd_list 	*prev; /* previous element in the list */
+	struct fd_list 	*head; /* head of the list */
+	void		*o;    /* additional pointer, used for any purpose (ex: start of the parent object) */
+};
+
+/* Initialize a list element */
+#define FD_LIST_INITIALIZER( _list_name ) \
+	{ .next = & _list_name, .prev = & _list_name, .head = & _list_name, .o = NULL }
+#define FD_LIST_INITIALIZER_O( _list_name, _obj ) \
+	{ .next = & _list_name, .prev = & _list_name, .head = & _list_name, .o = _obj }
+void fd_list_init ( struct fd_list * list, void * obj );
+
+/* Return boolean, true if the list is empty */
+#define FD_IS_LIST_EMPTY( _list ) ((((struct fd_list *)(_list))->head == (_list)) && (((struct fd_list *)(_list))->next == (_list)))
+
+/* Insert an item in a list at known position */
+void fd_list_insert_after  ( struct fd_list * ref, struct fd_list * item );
+void fd_list_insert_before ( struct fd_list * ref, struct fd_list * item );
+
+/* Move all elements from a list at the end of another */
+void fd_list_move_end(struct fd_list * ref, struct fd_list * senti);
+
+/* Insert an item in an ordered list -- ordering function must be provided. If duplicate object found, EEXIST and it is returned in ref_duplicate */
+int fd_list_insert_ordered( struct fd_list * head, struct fd_list * item, int (*cmp_fct)(void *, void *), void ** ref_duplicate);
+
+/* Unlink an item from a list */
+void fd_list_unlink ( struct fd_list * item );
+
+
+
+/*============================================================*/
+/*                          HASH                              */
+/*============================================================*/
+
+/* Compute a hash value of a string (session id, diameter id, ...) */
+uint32_t fd_hash ( char * string, size_t len );
+
+
+
+/*============================================================*/
+/*                        DICTIONARY                          */
+/*============================================================*/
+
+/* Structure that contains the complete dictionary definitions */
+struct dictionary;
+
+/* Structure that contains a dictionary object */
+struct dict_object;
+
+/* Types of object in the dictionary. */
+enum dict_object_type {
+	DICT_VENDOR	= 1,	/* Vendor */
+	DICT_APPLICATION,	/* Diameter Application */
+	DICT_TYPE,		/* AVP data type */
+	DICT_ENUMVAL,		/* Named constant (value of an enumerated AVP type) */
+	DICT_AVP,		/* AVP */
+	DICT_COMMAND,		/* Diameter Command */
+	DICT_RULE		/* a Rule for AVP in command or grouped AVP */
+#define DICT_TYPE_MAX	DICT_RULE
+};
+	
+/* Initialize a dictionary */
+int fd_dict_init(struct dictionary ** dict);
+/* Destroy a dictionary */
+int fd_dict_fini(struct dictionary ** dict);
+
+/*
+ * FUNCTION:	fd_dict_new
+ *
+ * PARAMETERS:
+ *  dict	: Pointer to the dictionnary where the object is created
+ *  type 	: What kind of object must be created
+ *  data 	: pointer to the data for the object. 
+ *          	 type parameter is used to determine the type of data (see bellow for detail).
+ *  parent 	: a reference to a parent object, if needed.
+ *  ref 	: upon successful creation, reference to new object is stored here if !null.
+ *
+ * DESCRIPTION: 
+ *  Create a new object in the dictionary. 
+ *  See following object sections in this header file for more information on data and parent parameters format.
+ *
+ * RETURN VALUE:
+ *  0      	: The object is created in the dictionary.
+ *  EINVAL 	: A parameter is invalid.
+ *  EEXIST 	: This object is already defined in the dictionary (with conflicting data). 
+ *                If "ref" is not NULL, it points to the existing element on return.
+ *  (other standard errors may be returned, too, with their standard meaning. Example:
+ *    ENOMEM 	: Memory allocation for the new object element failed.)
+ */
+int fd_dict_new ( struct dictionary * dict, enum dict_object_type type, void * data, struct dict_object * parent, struct dict_object ** ref );
+
+/*
+ * FUNCTION: 	fd_dict_search
+ *
+ * PARAMETERS:
+ *  dict	: Pointer to the dictionnary where the object is searched
+ *  type 	: type of object that is being searched
+ *  criteria 	: how the object must be searched. See object-related sections bellow for more information.
+ *  what 	: depending on criteria, the data that must be searched.
+ *  result 	: On successful return, pointer to the object is stored here.
+ *  retval	: this value is returned if the object is not found and result is not NULL.
+ *
+ * DESCRIPTION: 
+ *   Perform a search in the dictionary. 
+ *   See the object-specific sections bellow to find how to look for each objects.
+ *   If the "result" parameter is NULL, the function is used to check if an object is in the dictionary.
+ *   Otherwise, a reference to the object is stored in result if found.
+ *   If result is not NULL and the object is not found, retval is returned (should be 0 or ENOENT usually)
+ *
+ * RETURN VALUE:
+ *  0      	: The object has been found in the dictionary, or *result is NULL.
+ *  EINVAL 	: A parameter is invalid.
+ *  ENOENT	: No matching object has been found, and result was NULL.
+ */
+int fd_dict_search ( struct dictionary * dict, enum dict_object_type type, int criteria, void * what, struct dict_object ** result, int retval );
+
+/* Special case: get the generic error command object */
+int fd_dict_get_error_cmd(struct dictionary * dict, struct dict_object ** obj);
+
+/*
+ * FUNCTION:	fd_dict_getval
+ *
+ * PARAMETERS:
+ *  object 	: Pointer to a dictionary object.
+ *  data 	: pointer to a structure to hold the data for the object.
+ *          	  The type is the same as "data" parameter in fd_dict_new function.
+ *
+ * DESCRIPTION: 
+ *  Retrieve content of a dictionary object.
+ *  See following object sections in this header file for more information on data and parent parameters format.
+ *
+ * RETURN VALUE:
+ *  0      	: The content of the object has been retrieved.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_dict_getval ( struct dict_object * object, void * val);
+int fd_dict_gettype ( struct dict_object * object, enum dict_object_type * type);
+int fd_dict_getdict ( struct dict_object * object, struct dictionary ** dict);
+
+/* Debug functions */
+void fd_dict_dump_object(struct dict_object * obj);
+void fd_dict_dump(struct dictionary * dict);
+
+/*
+ ***************************************************************************
+ *
+ * Vendor object 
+ *
+ * These types are used to manage vendors in the dictionary
+ *
+ ***************************************************************************
+ */
+
+/* Type to hold a Vendor ID: "SMI Network Management Private Enterprise Codes" (RFC3232) */
+typedef uint32_t	vendor_id_t;
+
+/* Type to hold data associated to a vendor */
+struct dict_vendor_data {
+	vendor_id_t	 vendor_id;	/* ID of a vendor */
+	char 		*vendor_name;	/* The name of this vendor */
+};
+
+/* The criteria for searching a vendor object in the dictionary */
+enum {
+	VENDOR_BY_ID = 10,	/* "what" points to a vendor_id_t */
+	VENDOR_BY_NAME,		/* "what" points to a string */
+	VENDOR_OF_APPLICATION	/* "what" points to a struct dict_object containing an application (see bellow) */
+};
+
+/***
+ *  API usage :
+
+Note: the value of "vendor_name" is copied when the object is created, and the string may be disposed afterwards.
+On the other side, when value is retrieved with dict_getval, the string is not copied and MUST NOT be freed. It will
+be freed automatically along with the object itself with call to dict_fini later.
+ 
+- fd_dict_new:
+ The "parent" parameter is not used for vendors. 
+ Sample code to create a vendor:
+ {
+	 int ret;
+	 struct dict_object * myvendor;
+	 struct dict_vendor_data myvendordata = { 23455, "my vendor name" };  -- just an example...
+	 ret = fd_dict_new ( dict, DICT_VENDOR, &myvendordata, NULL, &myvendor );
+ }
+
+- fd_dict_search:
+ Sample codes to look for a vendor object, by its id or name:
+ {
+	 int ret;
+	 struct dict_object * vendor_found;
+	 vendor_id_t vendorid = 23455;
+	 ret = fd_dict_search ( dict, DICT_VENDOR, VENDOR_BY_ID, &vendorid, &vendor_found, ENOENT);
+	 - or -
+	 ret = fd_dict_search ( dict, DICT_VENDOR, VENDOR_BY_NAME, "my vendor name", &vendor_found, ENOENT);
+ }
+ 
+ - fd_dict_getval:
+ Sample code to retrieve the data from a vendor object:
+ {
+	 int ret;
+	 struct dict_object * myvendor;
+	 struct dict_vendor_data myvendordata;
+	 ret = fd_dict_search ( dict, DICT_VENDOR, VENDOR_BY_NAME, "my vendor name", &myvendor, ENOENT);
+	 ret = fd_dict_getval ( myvendor, &myvendordata );
+	 printf("my vendor id: %d\n", myvendordata.vendor_id );
+ }
+		 
+*/
+		
+/* Special function: */
+uint32_t * fd_dict_get_vendorid_list(struct dictionary * dict);
+	 
+/*
+ ***************************************************************************
+ *
+ * Application object 
+ *
+ * These types are used to manage Diameter applications in the dictionary
+ *
+ ***************************************************************************
+ */
+
+/* Type to hold a Diameter application ID: IANA assigned value for this application. */
+typedef uint32_t	application_id_t;
+
+/* Type to hold data associated to an application */
+struct dict_application_data {
+	application_id_t	 application_id;	/* ID of the application */
+	char 			*application_name;	/* The name of this application */
+};
+
+/* The criteria for searching an application object in the dictionary */
+enum {
+	APPLICATION_BY_ID = 20,		/* "what" points to a application_id_t */
+	APPLICATION_BY_NAME,		/* "what" points to a string */
+	APPLICATION_OF_TYPE,		/* "what" points to a struct dict_object containing a type object (see bellow) */
+	APPLICATION_OF_COMMAND		/* "what" points to a struct dict_object containing a command (see bellow) */
+};
+
+/***
+ *  API usage :
+
+The "parent" parameter of dict_new may point to a vendor object to inform of what vendor defines the application.
+for standard-track applications, the "parent" parameter should be NULL.
+The vendor associated to an application is retrieved with VENDOR_OF_APPLICATION search criteria on vendors.
+
+- fd_dict_new:
+ Sample code for application creation:
+ {
+	 int ret;
+	 struct dict_object * vendor;
+	 struct dict_object * appl;
+	 struct dict_vendor_data vendor_data = {
+		 23455,
+		 "my vendor name"
+	 };
+	 struct dict_application_data app_data = {
+		 9789,
+		 "my vendor's application"
+	 };
+	
+	 ret = fd_dict_new ( dict, DICT_VENDOR, &vendor_data, NULL, &vendor );
+	 ret = fd_dict_new ( dict, DICT_APPLICATION, &app_data, vendor, &appl );
+ }
+
+- fd_dict_search:
+ Sample code to retrieve the vendor of an application
+ {
+	 int ret;
+	 struct dict_object * vendor, * appli;
+	 
+	 ret = fd_dict_search ( dict, DICT_APPLICATION, APPLICATION_BY_NAME, "my vendor's application", &appli, ENOENT);
+	 ret = fd_dict_search ( dict, DICT_VENDOR, VENDOR_OF_APPLICATION, appli, &vendor, ENOENT);
+ }
+ 
+ - fd_dict_getval:
+ Sample code to retrieve the data from an application object:
+ {
+	 int ret;
+	 struct dict_object * appli;
+	 struct dict_application_data appl_data;
+	 ret = fd_dict_search ( dict, DICT_APPLICATION, APPLICATION_BY_NAME, "my vendor's application", &appli, ENOENT);
+	 ret = fd_dict_getval ( appli, &appl_data );
+	 printf("my application id: %s\n", appl_data.application_id );
+ }
+
+*/
+
+/*
+ ***************************************************************************
+ *
+ * Type object 
+ *
+ * These types are used to manage AVP data types in the dictionary
+ *
+ ***************************************************************************
+ */
+
+/* Type to store any AVP value */ 
+union avp_value {
+	struct {
+		uint8_t *data;	/* bytes buffer */
+		size_t   len;	/* length of the data buffer */
+	}           os;		/* Storage for an octet string, data is alloc'd and must be freed */
+	int32_t     i32;	/* integer 32 */
+	int64_t     i64;	/* integer 64 */
+	uint32_t    u32;	/* unsigned 32 */
+	uint64_t    u64;	/* unsigned 64 */
+	float       f32;	/* float 32 */
+	double 	    f64;	/* float 64 */
+};
+
+/* These are the basic AVP types defined in RFC3588bis */
+enum dict_avp_basetype {
+	AVP_TYPE_GROUPED,
+	AVP_TYPE_OCTETSTRING,
+	AVP_TYPE_INTEGER32,
+	AVP_TYPE_INTEGER64,
+	AVP_TYPE_UNSIGNED32,
+	AVP_TYPE_UNSIGNED64,
+	AVP_TYPE_FLOAT32,
+	AVP_TYPE_FLOAT64
+#define AVP_TYPE_MAX AVP_TYPE_FLOAT64
+};
+
+/* Callbacks that can be associated with a derived type to easily interpret the AVP value. */
+/*
+ * CALLBACK:	dict_avpdata_interpret
+ *
+ * PARAMETERS:
+ *   val         : Pointer to the AVP value that must be interpreted.
+ *   interpreted : The result of interpretation is stored here. The format and meaning depends on each type.
+ *
+ * DESCRIPTION: 
+ *   This callback can be provided with a derived type in order to facilitate the interpretation of formated data.
+ *  For example, when an AVP of type "Address" is received, it can be used to convert the octetstring into a struct sockaddr.
+ *  This callback is not called directly, but through the message's API msg_avp_value_interpret function.
+ *
+ * RETURN VALUE:
+ *  0      	: Operation complete.
+ *  !0 		: An error occurred, the error code is returned.
+ */
+typedef int (*dict_avpdata_interpret) (union avp_value * value, void * interpreted);
+/*
+ * CALLBACK:	dict_avpdata_encode
+ *
+ * PARAMETERS:
+ *   data	: The formated data that must be stored in the AVP value.
+ *   val	: Pointer to the AVP value storage area where the data must be stored.
+ *
+ * DESCRIPTION: 
+ *   This callback can be provided with a derived type in order to facilitate the encoding of formated data.
+ *  For example, it can be used to convert a struct sockaddr in an AVP value of type Address.
+ *  This callback is not called directly, but through the message's API msg_avp_value_encode function.
+ *  If the callback is defined for an OctetString based type, the created string must be malloc'd. free will be called 
+ *  automatically later.
+ *
+ * RETURN VALUE:
+ *  0      	: Operation complete.
+ *  !0 		: An error occurred, the error code is returned.
+ */
+typedef int (*dict_avpdata_encode) (void * data, union avp_value * val);
+
+
+/* Type to hold data associated to a derived AVP data type */
+struct dict_type_data {
+	enum dict_avp_basetype	 type_base;	/* How the data of such AVP must be interpreted */
+	char 			*type_name;	/* The name of this type */
+	dict_avpdata_interpret	 type_interpret;/* cb to convert the AVP value in more comprehensive format (or NULL) */
+	dict_avpdata_encode	 type_encode;	/* cb to convert formatted data into an AVP value (or NULL) */
+	void			(*type_dump)(union avp_value * val);	/* cb called by fd_msg_dump_one for this type of data (if != NULL), to dump the AVP value in debug */
+};
+
+/* The criteria for searching a type object in the dictionary */
+enum {
+	TYPE_BY_NAME = 30,		/* "what" points to a string */
+	TYPE_OF_ENUMVAL,		/* "what" points to a struct dict_object containing an enumerated constant (DICT_ENUMVAL, see bellow). */
+	TYPE_OF_AVP			/* "what" points to a struct dict_object containing an AVP object. */
+};
+
+
+/***
+ *  API usage :
+
+- fd_dict_new:
+ The "parent" parameter may point to an application object, when a type is defined by a Diameter application. 
+ 
+ Sample code:
+ {
+	 int ret;
+	 struct dict_object * mytype;
+	 struct dict_type_data mytypedata = 
+		{ 
+		 AVP_TYPE_OCTETSTRING,
+		 "Address",
+		 NULL,
+		 NULL
+		};
+	 ret = fd_dict_new ( dict, DICT_TYPE, &mytypedata, NULL, &mytype );
+ }
+
+- fd_dict_search:
+ Sample code:
+ {
+	 int ret;
+	 struct dict_object * address_type;
+	 ret = fd_dict_search ( dict, DICT_TYPE, TYPE_BY_NAME, "Address", &address_type, ENOENT);
+ }
+ 
+*/
+	 
+/*
+ ***************************************************************************
+ *
+ * Enumerated values object 
+ *
+ * These types are used to manage named constants of some AVP,
+ * for enumerated types. freeDiameter allows constants for types others than Unsigned32
+ *
+ ***************************************************************************
+ */
+
+/* Type to hold data of named constants for AVP */
+struct dict_enumval_data {
+	char 		*enum_name;	/* The name of this constant */
+	union avp_value  enum_value;	/* Value of the constant. Union term depends on parent type's base type. */
+};
+
+/* The criteria for searching a constant in the dictionary */
+enum {
+	ENUMVAL_BY_STRUCT = 40,	/* "what" points to a struct dict_enumval_request as defined bellow */
+};
+
+struct dict_enumval_request {
+	/* Identifier of the parent type, one of the following must not be NULL */
+	struct dict_object	*type_obj;
+	char			*type_name;
+	
+	/* Search criteria for the constant */
+	struct dict_enumval_data search; /* search.enum_value is used only if search.enum_name == NULL */
+};
+
+/***
+ *  API usage :
+
+- fd_dict_new:
+ The "parent" parameter must point to a derived type object. 
+ Sample code to create a type "Boolean" with two constants "True" and "False":
+ {
+	 int ret;
+	 struct dict_object * type_boolean;
+	 struct dict_type_data type_boolean_data = 
+		{ 
+		 AVP_TYPE_INTEGER32,
+		 "Boolean",
+		 NULL,
+		 NULL
+		};
+	 struct dict_enumval_data boolean_false =
+	 	{
+		 .enum_name="False",
+		 .enum_value.i32 = 0
+	 	};
+	 struct dict_enumval_data boolean_true =
+	 	{
+		 .enum_name="True",
+		 .enum_value.i32 = -1
+	 	};
+	 ret = fd_dict_new ( dict, DICT_TYPE, &type_boolean_data, NULL, &type_boolean );
+	 ret = fd_dict_new ( dict, DICT_ENUMVAL, &boolean_false, type_boolean, NULL );
+	 ret = fd_dict_new ( dict, DICT_ENUMVAL, &boolean_true , type_boolean, NULL );
+	 
+ }
+
+- fd_dict_search:
+ Sample code to look for a constant name, by its value:
+ {
+	 int ret;
+	 struct dict_object * value_found;
+	 struct dict_enumval_request boolean_by_value =
+	 	{
+		 .type_name = "Boolean",
+		 .search.enum_name=NULL,
+		 .search.enum_value.i32 = -1
+	 	};
+	 
+	 ret = fd_dict_search ( dict, DICT_ENUMVAL, ENUMVAL_BY_STRUCT, &boolean_by_value, &value_found, ENOENT);
+ }
+ 
+ - fd_dict_getval:
+ Sample code to retrieve the data from a constant object:
+ {
+	 int ret;
+	 struct dict_object * value_found;
+	 struct dict_enumval_data boolean_data = NULL;
+	 struct dict_enumval_request boolean_by_value =
+	 	{
+		 .type_name = "Boolean",
+		 .search.enum_name=NULL,
+		 .search.enum_value.i32 = 0
+	 	};
+	 
+	 ret = fd_dict_search ( dict, DICT_ENUMVAL, ENUMVAL_BY_STRUCT, &boolean_by_value, &value_found, ENOENT);
+	 ret = fd_dict_getval ( value_found, &boolean_data );
+	 printf(" Boolean with value 0: %s", boolean_data.enum_name );
+ }
+*/
+	 
+/*
+ ***************************************************************************
+ *
+ * AVP object 
+ *
+ * These objects are used to manage AVP definitions in the dictionary
+ *
+ ***************************************************************************
+ */
+
+/* Type to hold an AVP code. For vendor 0, these codes are assigned by IANA. Otherwise, it is managed by the vendor */
+typedef uint32_t	avp_code_t;
+
+/* Values of AVP flags */
+#define	AVP_FLAG_VENDOR	  	0x80
+#define	AVP_FLAG_MANDATORY	0x40
+#define	AVP_FLAG_RESERVED3	0x20
+#define	AVP_FLAG_RESERVED4	0x10
+#define	AVP_FLAG_RESERVED5	0x08
+#define	AVP_FLAG_RESERVED6	0x04
+#define	AVP_FLAG_RESERVED7	0x02
+#define	AVP_FLAG_RESERVED8	0x01
+
+/* For dumping flags and values */
+#define DUMP_AVPFL_str	"%c%c"
+#define DUMP_AVPFL_val(_val) (_val & AVP_FLAG_VENDOR)?'V':'-' , (_val & AVP_FLAG_MANDATORY)?'M':'-'
+
+/* Type to hold data associated to an avp */
+struct dict_avp_data {
+	avp_code_t	 	 avp_code;	/* Code of the avp */
+	vendor_id_t	 	 avp_vendor;	/* Vendor of the AVP, or 0 */
+	char			*avp_name;	/* Name of this AVP */
+	uint8_t		 	 avp_flag_mask;	/* Mask of fixed AVP flags */
+	uint8_t		 	 avp_flag_val;	/* Values of the fixed flags */
+	enum dict_avp_basetype 	 avp_basetype;	/* Basic type of data found in the AVP */
+};
+
+/* The criteria for searching an avp object in the dictionary */
+enum {
+	AVP_BY_CODE = 50,	/* "what" points to an avp_code_t, vendor is always 0 */
+	AVP_BY_NAME,		/* "what" points to a string, vendor is always 0 */
+	AVP_BY_CODE_AND_VENDOR,	/* "what" points to a struct dict_avp_request (see bellow), where avp_vendor and avp_code are set */
+	AVP_BY_NAME_AND_VENDOR,	/* "what" points to a struct dict_avp_request (see bellow), where avp_vendor and avp_name are set */
+	AVP_BY_NAME_ALL_VENDORS /* "what" points to a string. Might be quite slow... */
+};
+
+/* Struct used for some researchs */
+struct dict_avp_request {
+	vendor_id_t	 avp_vendor;
+	avp_code_t	 avp_code;
+	char		*avp_name;
+};
+
+
+/***
+ *  API usage :
+
+If "parent" parameter is not NULL during AVP creation, it must point to a DICT_TYPE object. 
+The extended type is then attached to the AVP. In case where it is an enumerated type, the value of 
+AVP is automatically interpreted in debug messages, and in message checks.
+The derived type of an AVP can be retrieved with: dict_search ( DICT_TYPE, TYPE_OF_AVP, avp, ... )
+
+To create the rules (ABNF) for children of Grouped AVP, see the DICT_RULE related part.
+
+- fd_dict_new:
+ Sample code for AVP creation:
+ {
+	 int ret;
+	 struct dict_object * user_name_avp;
+	 struct dict_object * boolean_type;
+	 struct dict_object * sample_boolean_avp;
+	 struct dict_avp_data user_name_data = {
+		 1,					// code
+		 0,					// vendor
+		 "User-Name",				// name
+		 AVP_FLAG_VENDOR | AVP_FLAG_MANDATORY,	// fixed mask: V and M values must always be defined as follow. other flags can be set or cleared
+		 AVP_FLAG_MANDATORY,			// the V flag must be cleared, the M flag must be set.
+		 AVP_TYPE_OCTETSTRING			// User-Name AVP contains OctetString data (further precision such as UTF8String can be given with a parent derived type)
+	 };
+	 struct dict_avp_data sample_boolean_data = {
+		 31337,
+		 23455,
+		 "Sample-Boolean",
+		 AVP_FLAG_VENDOR | AVP_FLAG_MANDATORY,
+		 AVP_FLAG_VENDOR,
+		 AVP_TYPE_INTEGER32			// This MUST be the same as parent type's
+	 };
+	
+ 	 -- Create an AVP with a base type --
+	 ret = fd_dict_new ( dict, DICT_AVP, &user_name_data, NULL, &user_name_avp );
+	 
+	 -- Create an AVP with a derived type --
+	 ret = fd_dict_search ( dict, DICT_TYPE, TYPE_BY_NAME, "Boolean", &boolean_type, ENOENT);
+	 ret = fd_dict_new ( dict, DICT_AVP, &sample_boolean_data , boolean_type, &sample_boolean_avp );
+	 
+ }
+
+- fd_dict_search:
+ Sample code to look for an AVP
+ {
+	 int ret;
+	 struct dict_object * avp_username;
+	 struct dict_object * avp_sampleboolean;
+	 struct dict_avp_request avpvendorboolean =
+	 	{
+		 .avp_vendor = 23455,
+		 .avp_name   = "Sample-Boolean"
+	 	};
+	 
+	 ret = fd_dict_search ( dict, DICT_AVP, AVP_BY_NAME, "User-Name", &avp_username, ENOENT);
+	 
+	 ret = fd_dict_search ( dict, DICT_AVP, AVP_BY_NAME_AND_VENDOR, &avpvendorboolean, &avp_sampleboolean, ENOENT);
+	 
+ }
+ 
+ - fd_dict_getval:
+ Sample code to retrieve the data from an AVP object:
+ {
+	 int ret;
+	 struct dict_object * avp_username;
+	 struct dict_avp_data user_name_data;
+	 ret = fd_dict_search ( dict, DICT_AVP, AVP_BY_NAME, "User-Name", &avp_username, ENOENT);
+	 ret = fd_dict_getval ( avp_username, &user_name_data );
+	 printf("User-Name code: %d\n", user_name_data.avp_code );
+ }
+
+*/
+
+/*
+ ***************************************************************************
+ *
+ * Command object 
+ *
+ * These types are used to manage commands objects in the dictionary
+ *
+ ***************************************************************************
+ */
+
+/* Type to hold a Diameter command code: IANA assigned values. 0x0-0x7fffff=standard, 0x800000-0xfffffd=vendors, 0xfffffe-0xffffff=experimental */
+typedef uint32_t	command_code_t;
+
+/* Values of command flags */
+#define CMD_FLAG_REQUEST	0x80
+#define CMD_FLAG_PROXIABLE	0x40
+#define CMD_FLAG_ERROR		0x20
+#define CMD_FLAG_RETRANSMIT	0x10
+#define CMD_FLAG_RESERVED5	0x08
+#define CMD_FLAG_RESERVED6	0x04
+#define CMD_FLAG_RESERVED7	0x02
+#define CMD_FLAG_RESERVED8	0x01
+
+/* For dumping flags and values */
+#define DUMP_CMDFL_str	"%c%c%c%c"
+#define DUMP_CMDFL_val(_val) (_val & CMD_FLAG_REQUEST)?'R':'-' , (_val & CMD_FLAG_PROXIABLE)?'P':'-' , (_val & CMD_FLAG_ERROR)?'E':'-' , (_val & CMD_FLAG_RETRANSMIT)?'T':'-'
+
+/* Type to hold data associated to a command */
+struct dict_cmd_data {
+	command_code_t	 cmd_code;	/* code of the command */
+	char		*cmd_name;	/* Name of the command */
+	uint8_t		 cmd_flag_mask;	/* Mask of fixed-value flags */
+	uint8_t		 cmd_flag_val;	/* values of the fixed flags */
+};
+
+/* The criteria for searching an avp object in the dictionary */
+enum {
+	CMD_BY_NAME = 60,	/* "what" points to a string */
+	CMD_BY_CODE_R,		/* "what" points to a command_code_t. The "Request" command is returned. */
+	CMD_BY_CODE_A,		/* "what" points to a command_code_t. The "Answer" command is returned. */
+	CMD_ANSWER		/* "what" points to a struct dict_object of a request command. The corresponding "Answer" command is returned. */
+};
+
+
+/***
+ *  API usage :
+
+The "parent" parameter of dict_new may point to an application object to inform of what application defines the command.
+The application associated to a command is retrieved with APPLICATION_OF_COMMAND search criteria on applications.
+
+To create the rules for children of commands, see the DICT_RULE related part.
+
+Note that the "Request" and "Answer" commands are two independant objects. This allows to have different rules for each.
+
+- fd_dict_new:
+ Sample code for command creation:
+ {
+	 int ret;
+	 struct dict_object * cer;
+	 struct dict_object * cea;
+	 struct dict_cmd_data ce_data = {
+		 257,					// code
+		 "Capabilities-Exchange-Request",	// name
+		 CMD_FLAG_REQUEST,			// mask
+		 CMD_FLAG_REQUEST			// value. Only the "R" flag is constrained here, set.
+	 };
+	
+	 ret = fd_dict_new (dict,  DICT_COMMAND, &ce_data, NULL, &cer );
+	 
+	 ce_data.cmd_name = "Capabilities-Exchange-Answer";
+	 ce_data.cmd_flag_val = 0;			// Same constraint on "R" flag, but this time it must be cleared.
+
+	 ret = fd_dict_new ( dict, DICT_COMMAND, &ce_data, NULL, &cea );
+ }
+
+- fd_dict_search:
+ Sample code to look for a command
+ {
+	 int ret;
+	 struct dict_object * cer, * cea;
+	 command_code_t	code = 257;
+	 ret = fd_dict_search ( dict, DICT_COMMAND, CMD_BY_NAME, "Capabilities-Exchange-Request", &cer, ENOENT);
+	 ret = fd_dict_search ( dict, DICT_COMMAND, CMD_BY_CODE_R, &code, &cer, ENOENT);
+ }
+ 
+ - fd_dict_getval:
+ Sample code to retrieve the data from a command object:
+ {
+	 int ret;
+	 struct dict_object * cer;
+	 struct dict_object * cea;
+	 struct dict_cmd_data cea_data;
+	 ret = fd_dict_search ( dict, DICT_COMMAND, CMD_BY_NAME, "Capabilities-Exchange-Request", &cer, ENOENT);
+	 ret = fd_dict_search ( dict, DICT_COMMAND, CMD_ANSWER, cer, &cea, ENOENT);
+	 ret = fd_dict_getval ( cea, &cea_data );
+	 printf("Answer to CER: %s\n", cea_data.cmd_name );
+ }
+
+*/
+
+/*
+ ***************************************************************************
+ *
+ * Rule object
+ *
+ * These objects are used to manage rules in the dictionary (ABNF implementation)
+ * This is used for checking messages validity (more powerful than a DTD)
+ *
+ ***************************************************************************
+ */
+
+/* This defines the kind of rule that is defined */
+enum rule_position {
+	RULE_FIXED_HEAD = 1,	/* The AVP must be at the head of the group. The rule_order field is used to specify the position. */
+	RULE_REQUIRED,		/* The AVP must be present in the parent, but its position is not defined. */
+	RULE_OPTIONAL,		/* The AVP may be present in the message. Used to specify a max number of occurences for example */
+	RULE_FIXED_TAIL		/* The AVP must be at the end of the group. The rule_order field is used to specify the position. */
+};
+
+/* Content of a RULE object data */
+struct dict_rule_data {
+	struct dict_object	*rule_avp;	/* Pointer to the AVP object that is concerned by this rule */
+	enum rule_position	 rule_position;	/* The position in which the rule_avp must appear in the parent */
+	unsigned		 rule_order;	/* for RULE_FIXED_* rules, the place. 1,2,3.. for HEAD rules; ...,3,2,1 for TAIL rules. */
+	int	 		 rule_min;	/* Minimum number of occurences. -1 means "default": 0 for optional rules, 1 for other rules */
+	int			 rule_max;	/* Maximum number of occurences. -1 means no maximum. 0 means the AVP is forbidden. */
+};
+
+/* The criteria for searching a rule in the dictionary */
+enum {
+	RULE_BY_AVP_AND_PARENT = 70	/* "what" points to a struct dict_rule_request -- see bellow. This is used to query "what is the rule for this AVP in this group?" */
+};
+
+/* Structure for querying the dictionary about a rule */
+struct dict_rule_request {
+	struct dict_object	*rule_parent;	/* The grouped avp or command to which the rule apply */
+	struct dict_object	*rule_avp;	/* The AVP concerned by this rule */
+};
+
+
+/***
+ *  API usage :
+
+The "parent" parameter can not be NULL. It points to the object (grouped avp or command) to which this rule apply (i.e. for which the ABNF is defined).
+
+- fd_dict_new:
+ Sample code for rule creation. Let's create the Proxy-Info grouped AVP for example.
+ {
+	int ret;
+	struct dict_object * proxy_info_avp;
+	struct dict_object * proxy_host_avp;
+	struct dict_object * proxy_state_avp;
+	struct dict_object * diameteridentity_type;
+	struct dict_rule_data rule_data;
+	struct dict_type_data di_type_data = { AVP_TYPE_OCTETSTRING, "DiameterIdentity", NULL, NULL };
+	struct dict_avp_data proxy_info_data = { 284, 0, "Proxy-Info", AVP_FLAG_VENDOR | AVP_FLAG_MANDATORY, AVP_FLAG_MANDATORY, AVP_TYPE_GROUPED };
+	struct dict_avp_data proxy_host_data = { 280, 0, "Proxy-Host", AVP_FLAG_VENDOR | AVP_FLAG_MANDATORY, AVP_FLAG_MANDATORY, AVP_TYPE_OCTETSTRING };
+	struct dict_avp_data proxy_state_data = { 33, 0, "Proxy-State",AVP_FLAG_VENDOR | AVP_FLAG_MANDATORY, AVP_FLAG_MANDATORY, AVP_TYPE_OCTETSTRING };
+	
+	-- Create the parent AVP
+	ret = fd_dict_new ( dict, DICT_AVP, &proxy_info_data, NULL, &proxy_info_avp );
+	
+	-- Create the first child AVP.
+	ret = fd_dict_new ( dict, DICT_TYPE, &di_type_data, NULL, &diameteridentity_type );
+	ret = fd_dict_new ( dict, DICT_AVP, &proxy_host_data, diameteridentity_type, &proxy_host_avp );
+	
+	-- Create the other child AVP
+	ret = fd_dict_new ( dict, DICT_AVP, &proxy_state_data, NULL, &proxy_state_avp );
+	
+	-- Now we can create the rules. Both children AVP are mandatory.
+	rule_data.rule_position = RULE_REQUIRED;
+	rule_data.rule_min = -1;
+	rule_data.rule_max = -1;
+	
+	rule_data.rule_avp = proxy_host_avp;
+	ret = fd_dict_new ( dict, DICT_RULE, &rule_data, proxy_info_avp, NULL );
+	
+	rule_data.rule_avp = proxy_state_avp;
+	ret = fd_dict_new ( dict, DICT_RULE, &rule_data, proxy_info_avp, NULL );
+}
+
+- fd_dict_search and fd_dict_getval are similar to previous examples.
+
+*/
+		
+/* Define some hard-coded values */
+/* Application */
+#define AI_RELAY			0xffffffff
+
+/* Commands Codes */
+#define CC_CAPABILITIES_EXCHANGE	257
+#define CC_RE_AUTH			258
+#define CC_ACCOUNTING			271
+#define CC_ABORT_SESSION		274
+#define CC_SESSION_TERMINATION		275
+#define CC_DEVICE_WATCHDOG		280
+#define CC_DISCONNECT_PEER		282
+
+/* AVPs (Vendor 0) */
+#define AC_USER_NAME			1
+#define AC_PROXY_STATE			33
+#define AC_HOST_IP_ADDRESS		257
+#define AC_AUTH_APPLICATION_ID		258
+#define AC_ACCT_APPLICATION_ID		259
+#define AC_VENDOR_SPECIFIC_APPLICATION_ID 260
+#define AC_REDIRECT_HOST_USAGE		261
+#define AC_REDIRECT_MAX_CACHE_TIME	262
+#define AC_SESSION_ID 			263
+#define AC_ORIGIN_HOST			264
+#define AC_SUPPORTED_VENDOR_ID		265
+#define AC_VENDOR_ID			266
+#define AC_FIRMWARE_REVISION		267
+#define AC_RESULT_CODE			268
+#define AC_PRODUCT_NAME			269
+#define AC_DISCONNECT_CAUSE		273
+#define ACV_DC_REBOOTING			0
+#define ACV_DC_BUSY				1
+#define ACV_DC_NOT_FRIEND			2
+#define AC_ORIGIN_STATE_ID		278
+#define AC_FAILED_AVP			279
+#define AC_PROXY_HOST			280
+#define AC_ERROR_MESSAGE		281
+#define AC_ROUTE_RECORD			282
+#define AC_DESTINATION_REALM		283
+#define AC_PROXY_INFO			284
+#define AC_REDIRECT_HOST		292
+#define AC_DESTINATION_HOST		293
+#define AC_ERROR_REPORTING_HOST		294
+#define AC_ORIGIN_REALM			296
+#define AC_INBAND_SECURITY_ID		299
+#define ACV_ISI_NO_INBAND_SECURITY		0
+#define ACV_ISI_TLS				1
+
+/* Error codes */
+#define ER_DIAMETER_SUCCESS			2001
+#define ER_DIAMETER_REALM_NOT_SERVED		3003
+#define ER_DIAMETER_TOO_BUSY			3004
+#define ER_DIAMETER_REDIRECT_INDICATION		3006
+#define ER_ELECTION_LOST			4003
+
+
+/*============================================================*/
+/*                         SESSIONS                           */
+/*============================================================*/
+
+/* Modules that want to associate a state with a Session-Id must first register a handler of this type */
+struct session_handler;
+
+/* This opaque structure represents a session associated with a Session-Id */
+struct session;
+
+/* The state information that a module associate with a session -- each module defines its own data format */
+typedef void session_state;
+
+/* The following function must be called to activate the session expiry mechanism */
+int fd_sess_start(void);
+
+/*
+ * FUNCTION:	fd_sess_handler_create
+ *
+ * PARAMETERS:
+ *  handler	: location where the new handler must be stored.
+ *  cleanup	: a callback function that must be called when the session with associated data is destroyed.
+ *  opaque      : A pointer that is passed to the cleanup callback -- the content is never examined by the framework.
+ *
+ * DESCRIPTION: 
+ *  Create a new session handler. This is needed by a module to associate a state with a session object.
+ * The cleanup handler is called when the session timeout expires, or fd_sess_destroy is called. It must free
+ * the state associated with the session, and eventually trig other actions (send a STR, ...).
+ *
+ * RETURN VALUE:
+ *  0      	: The new handler has been created.
+ *  EINVAL 	: A parameter is invalid.
+ *  ENOMEM	: Not enough memory to complete the operation
+ */
+int fd_sess_handler_create_internal ( struct session_handler ** handler, void (*cleanup)(session_state * state, char * sid, void * opaque), void * opaque );
+/* Macro to avoid casting everywhere */
+#define fd_sess_handler_create( _handler, _cleanup, _opaque ) \
+	fd_sess_handler_create_internal( (_handler), (void (*)(session_state *, char *, void *))(_cleanup), (void *)(_opaque) )
+
+	
+/*
+ * FUNCTION:	fd_sess_handler_destroy
+ *
+ * PARAMETERS:
+ *  handler	: location of an handler created by fd_sess_handler_create.
+ *  opaque      : the opaque pointer registered with the callback is restored here (if ! NULL).
+ *
+ * DESCRIPTION: 
+ *  This destroys a session handler (typically called when an application is shutting down).
+ * If sessions states are registered with this handler, the cleanup callback is called on them.
+ *
+ * RETURN VALUE:
+ *  0      	: The handler was destroyed.
+ *  EINVAL 	: A parameter is invalid.
+ *  ENOMEM	: Not enough memory to complete the operation
+ */
+int fd_sess_handler_destroy ( struct session_handler ** handler, void **opaque );
+
+
+
+/*
+ * FUNCTION:	fd_sess_new
+ *
+ * PARAMETERS:
+ *  session	  : The location where the session object will be created upon success.
+ *  diamId	  : \0-terminated string containing a Diameter Identity.
+ *  opt           : Additional string. Usage is described bellow.
+ *  optlen	  : if opt is \0-terminated, this can be 0. Otherwise, the length of opt.
+ *
+ * DESCRIPTION: 
+ *   Create a new session object. The Session-Id string associated with this session is generated as follow:
+ *  If diamId parameter is provided, the string is created according to the RFC: <diamId>;<high32>;<low32>[;opt] where
+ *    diamId is a Diameter Identity.
+ *    high32 and low32 are the parts of a monotonic 64 bits counter initialized to (time, 0) at startup.
+ *    opt is an optional string that can be concatenated to the identifier.
+ *  If diamId is NULL, the string is exactly the content of opt.
+ *
+ * RETURN VALUE:
+ *  0      	: The session is created.
+ *  EINVAL 	: A parameter is invalid.
+ *  EALREADY	: A session with the same name already exists (returned in *session)
+ *  ENOMEM	: Not enough memory to complete the operation
+ */
+int fd_sess_new ( struct session ** session, char * diamId, char * opt, size_t optlen );
+
+/*
+ * FUNCTION:	fd_sess_fromsid
+ *
+ * PARAMETERS:
+ *  sid	  	: pointer to a string containing a Session-Id (UTF-8).
+ *  len		: length of the sid string (which does not need to be '\0'-terminated)
+ *  session	: On success, pointer to the session object created / retrieved.
+ *  isnew	: if not NULL, set to 1 on return if the session object has been created, 0 if it was simply retrieved.
+ *
+ * DESCRIPTION: 
+ *   Retrieve a session object from a Session-Id string. In case no session object was previously existing with this 
+ *  id, a new object is silently created (equivalent to fd_sess_new with flag SESSION_NEW_FULL).
+ *
+ * RETURN VALUE:
+ *  0      	: The session parameter has been updated.
+ *  EINVAL 	: A parameter is invalid.
+ *  ENOMEM	: Not enough memory to complete the operation
+ */
+int fd_sess_fromsid ( char * sid, size_t len, struct session ** session, int * isnew);
+
+/*
+ * FUNCTION:	fd_sess_getsid
+ *
+ * PARAMETERS:
+ *  session	: Pointer to a session object.
+ *  sid	  	: On success, the location of a (\0-terminated) string is stored here.
+ *
+ * DESCRIPTION: 
+ *   Retrieve the session identifier (Session-Id) corresponding to a session object.
+ *  The returned sid is an UTF-8 string terminated by \0, suitable for calls to strlen and strcpy.
+ *  It may be used for example to set the value of an AVP.
+ *  Note that the sid string is not copied, just its reference... do not free it!
+ *
+ * RETURN VALUE:
+ *  0      	: The sid parameter has been updated.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_sess_getsid ( struct session * session, char ** sid );
+
+/*
+ * FUNCTION:	fd_sess_settimeout
+ *
+ * PARAMETERS:
+ *  session	: The session for which to set the timeout.
+ *  timeout	: The date when the session times out.
+ *
+ * DESCRIPTION: 
+ *   Set the lifetime for a given session object. This function may be 
+ * called several times on the same object to update the timeout value.
+ *   When the timeout date is reached, the cleanup handler of each 
+ * module that registered data with this session is called, then the 
+ * session is cleared.
+ *
+ *   There is a possible race condition between cleanup of the session
+ * and use of its data; applications should ensure that they are not 
+ * using data from a session that is about to expire / expired.
+ *
+ * RETURN VALUE:
+ *  0      	: The session timeout has been updated.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_sess_settimeout( struct session * session, const struct timespec * timeout );
+
+/*
+ * FUNCTION:	fd_sess_destroy
+ *
+ * PARAMETERS:
+ *  session	: Pointer to a session object.
+ *
+ * DESCRIPTION: 
+ *   Destroys a session an all associated data, if any.
+ * Equivalent to a session timeout expired, but the effect is immediate.
+ *
+ * RETURN VALUE:
+ *  0      	: The session no longer exists.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_sess_destroy ( struct session ** session );
+
+/*
+ * FUNCTION:	fd_sess_reclaim
+ *
+ * PARAMETERS:
+ *  session	: Pointer to a session object.
+ *
+ * DESCRIPTION: 
+ *   Destroys the resources of a session, only if no session_state is associated with it.
+ *
+ * RETURN VALUE:
+ *  0      	: The session no longer exists.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_sess_reclaim ( struct session ** session );
+
+
+
+
+/*
+ * FUNCTION:	fd_sess_state_store
+ *
+ * PARAMETERS:
+ *  handler	: The handler with which the state is registered.
+ *  session	: The session object with which the state is registered.
+ *  state	: An application state (opaque data) to store with the session.
+ *
+ * DESCRIPTION: 
+ *  Stores an application state with a session. This state can later be retrieved
+ * with fd_sess_state_retrieve, or implicitly in the cleanup handler when the session
+ * is destroyed.
+ *
+ * RETURN VALUE:
+ *  0      	: The state has been stored.
+ *  EINVAL 	: A parameter is invalid.
+ *  EALREADY	: Data was already associated with this session and client.
+ *  ENOMEM	: Not enough memory to complete the operation
+ */
+int fd_sess_state_store_internal ( struct session_handler * handler, struct session * session, session_state ** state );
+#define fd_sess_state_store( _handler, _session, _state ) \
+	fd_sess_state_store_internal( (_handler), (_session), (void *)(_state) )
+
+/*
+ * FUNCTION:	fd_sess_state_retrieve
+ *
+ * PARAMETERS:
+ *  handler	: The handler with which the state was registered.
+ *  session	: The session object with which the state was registered.
+ *  state	: Location where the state must be saved if it is found.
+ *
+ * DESCRIPTION: 
+ *  Retrieves a state saved by fd_sess_state_store.
+ * After this function has been called, the state is no longer associated with 
+ * the session. A new call to fd_sess_state_store must be performed in order to
+ * store again the data with the session.
+ *
+ * RETURN VALUE:
+ *  0      	: *state is updated (NULL or points to the state if it was found).
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_sess_state_retrieve_internal ( struct session_handler * handler, struct session * session, session_state ** state ); 
+#define fd_sess_state_retrieve( _handler, _session, _state ) \
+	fd_sess_state_retrieve_internal( (_handler), (_session), (void *)(_state) )
+
+
+/* For debug */
+void fd_sess_dump(int level, struct session * session);
+void fd_sess_dump_hdl(int level, struct session_handler * handler);
+
+/*============================================================*/
+/*                         ROUTING                            */
+/*============================================================*/
+
+/* The following functions are helpers for the routing module. 
+  The routing data is stored in the message itself. */
+
+/* Structure that contains the routing data for a message */
+struct rt_data;
+
+/* Following functions are helpers to create the routing data of a message */
+int  fd_rtd_init(struct rt_data ** rtd);
+void fd_rtd_free(struct rt_data ** rtd);
+
+/* Add a peer to the candidates list */
+int  fd_rtd_candidate_add(struct rt_data * rtd, char * peerid, char * realm);
+
+/* Remove a peer from the candidates (if it is found) */
+void fd_rtd_candidate_del(struct rt_data * rtd, char * peerid, size_t sz /* if !0, peerid does not need to be \0 terminated */);
+
+/* Extract the list of valid candidates, and initialize their scores to 0 */
+void fd_rtd_candidate_extract(struct rt_data * rtd, struct fd_list ** candidates, int ini_score);
+
+/* If a peer returned a protocol error for this message, save it so that we don't try to send it there again */
+int  fd_rtd_error_add(struct rt_data * rtd, char * sentto, uint8_t * origin, size_t originsz, uint32_t rcode);
+
+/* The extracted list items have the following structure: */
+struct rtd_candidate {
+	struct fd_list	chain;	/* link in the list returned by the previous fct */
+	char *		diamid;	/* the diameter Id of the peer */
+	char *		realm;	/* the diameter realm of the peer (if known) */
+	int		score;	/* the current routing score for this peer, see fd_rt_out_register definition for details */
+};
+
+/* Reorder the list of peers */
+int  fd_rtd_candidate_reorder(struct fd_list * candidates);
+
+/* Note : it is fine for a callback to add a new entry in the candidates list after the list has been extracted. The diamid must then be malloc'd. */
+/* Beware that this could lead to routing loops */
+
+/*============================================================*/
+/*                         MESSAGES                           */
+/*============================================================*/
+
+/* The following types are opaque */
+struct	msg;	/* A message: command with children AVPs (possibly grand children) */
+struct	avp;	/* AVP object */
+
+/* Some details about chaining:
+ *
+ *  A message is made of a header ( msg ) and 0 or more AVPs ( avp ).
+ * The structure is a kind of tree, where some AVPs (grouped AVPs) can contain other AVPs.
+ * Exemple:
+ * msg
+ *  |-avp
+ *  |-gavp
+ *  |   |-avp
+ *  |   |-avp
+ *  |   \-avp
+ *  |-avp
+ *  \-avp
+ *
+ */
+
+/* The following type is used to point to either a msg or an AVP */
+typedef void msg_or_avp;
+
+/* The Diameter protocol version */
+#define DIAMETER_VERSION	1
+
+/* In the two following types, some fields are marked (READONLY). 
+ * This means that the content of these fields will be overwritten by the daemon so modifying it is useless.
+ */
+
+/* The following structure represents the header of a message. All data is in host byte order. */
+struct msg_hdr {
+	uint8_t		 msg_version;		/* (READONLY) Version of Diameter: must be DIAMETER_VERSION. */
+	uint32_t	 msg_length;		/* (READONLY)(3 bytes) indicates the length of the message */
+	uint8_t		 msg_flags;		/* Message flags: CMD_FLAG_* */
+	command_code_t	 msg_code;		/* (3 bytes) the command-code. See dictionary-api.h for more detail */
+	application_id_t msg_appl;		/* The application issuing this message */
+	uint32_t	 msg_hbhid;		/* The Hop-by-Hop identifier of the message */
+	uint32_t	 msg_eteid;		/* The End-to-End identifier of the message */
+};
+
+/* The following structure represents the visible content of an AVP. All data is in host byte order. */
+struct avp_hdr {
+	avp_code_t	 avp_code;		/* the AVP Code */
+	uint8_t		 avp_flags;		/* AVP_FLAG_* flags */
+	uint32_t	 avp_len;		/* (READONLY)(Only 3 bytes are used) the length of the AVP as described in the RFC */
+	vendor_id_t	 avp_vendor;		/* Only used if AVP_FLAG_VENDOR is present */
+	union avp_value *avp_value;		/* pointer to the value of the AVP. NULL means that the value is not set / not understood.
+						   One should not directly change this value. Use the msg_avp_setvalue function instead.
+						   The content of the pointed structure can be changed directly, with this restriction:
+						     if the AVP is an OctetString, and you change the value of the pointer avp_value->os.data, then
+						     you must call free() on the previous value, and the new one must be free()-able.
+						 */
+};
+
+/* The following enum is used to browse inside message hierarchy (msg, gavp, avp) */
+enum msg_brw_dir {
+	MSG_BRW_NEXT = 1,	/* Get the next element at the same level, or NULL if this is the last element. */
+	MSG_BRW_PREV,		/* Get the previous element at the same level, or NULL if this is the first element. */
+	MSG_BRW_FIRST_CHILD,	/* Get the first child AVP of this element, if any. */
+	MSG_BRW_LAST_CHILD,	/* Get the last child AVP of this element, if any. */
+	MSG_BRW_PARENT,		/* Get the parent element of this element, if any. Only the msg_t object has no parent. */
+	MSG_BRW_WALK		/* This is equivalent to FIRST_CHILD or NEXT or PARENT->next, first that is not NULL. Use this to walk inside all AVPs. */
+};
+
+/* Some flags used in the functions bellow */
+#define AVPFL_SET_BLANK_VALUE	0x01	/* When creating an AVP, initialize its value to a blank area */
+#define AVPFL_MAX		AVPFL_SET_BLANK_VALUE	/* The biggest valid flag value */
+	
+#define MSGFL_ALLOC_ETEID	0x01	/* When creating a message, a new end-to-end ID is allocated and set in the message */
+#define MSGFL_ANSW_ERROR	0x02	/* When creating an answer message, set the 'E' bit and use the generic error ABNF instead of command-specific ABNF */
+#define MSGFL_ANSW_NOSID	0x04	/* When creating an answer message, do not add the Session-Id even if present in request */
+#define MSGFL_MAX		MSGFL_ANSW_NOSID	/* The biggest valid flag value */
+
+/**************************************************/
+/*   Message creation, manipulation, disposal     */
+/**************************************************/
+/*
+ * FUNCTION:	fd_msg_avp_new
+ *
+ * PARAMETERS:
+ *  model 	: Pointer to a DICT_AVP dictionary object describing the avp to create, or NULL.
+ *  flags	: Flags to use in creation (AVPFL_*).
+ *  avp 	: Upon success, pointer to the new avp is stored here.
+ *
+ * DESCRIPTION: 
+ *   Create a new AVP instance.
+ *
+ * RETURN VALUE:
+ *  0      	: The AVP is created.
+ *  EINVAL 	: A parameter is invalid.
+ *  (other standard errors may be returned, too, with their standard meaning. Example:
+ *    ENOMEM 	: Memory allocation for the new avp failed.)
+ */
+int fd_msg_avp_new ( struct dict_object * model, int flags, struct avp ** avp );
+
+/*
+ * FUNCTION:	fd_msg_new
+ *
+ * PARAMETERS:
+ *  model 	: Pointer to a DICT_COMMAND dictionary object describing the message to create, or NULL.
+ *  flags	: combination of MSGFL_* flags.
+ *  msg 	: Upon success, pointer to the new message is stored here.
+ *
+ * DESCRIPTION: 
+ *   Create a new empty Diameter message. 
+ *
+ * RETURN VALUE:
+ *  0      	: The message is created.
+ *  EINVAL 	: A parameter is invalid.
+ *  (other standard errors may be returned, too, with their standard meaning. Example:
+ *    ENOMEM 	: Memory allocation for the new message failed.)
+ */
+int fd_msg_new ( struct dict_object * model, int flags, struct msg ** msg );
+
+/*
+ * FUNCTION:	msg_new_answer_from_req
+ *
+ * PARAMETERS:
+ *  dict	: Pointer to the dictionary containing the model of the query.
+ *  msg		: The location of the query on function call. Updated by the location of answer message on return.
+ *  flag        : Pass MSGFL_ANSW_ERROR to indicate if the answer is an error message (will set the 'E' bit)
+ *
+ * DESCRIPTION: 
+ *   This function creates the empty answer message corresponding to a request.
+ *  The header is set properly (R flag, ccode, appid, hbhid, eteid)
+ *  The Session-Id AVP is copied if present.
+ *  The calling code should usually call fd_msg_rescode_set function on the answer.
+ *  Upon return, the original query may be retrieved by calling fd_msg_answ_getq on the message.
+ *
+ * RETURN VALUE:
+ *  0      	: Operation complete.
+ *  !0      	: an error occurred.
+ */
+int fd_msg_new_answer_from_req ( struct dictionary * dict, struct msg ** msg, int flag );
+
+/*
+ * FUNCTION:	fd_msg_browse
+ *
+ * PARAMETERS:
+ *  reference 	: Pointer to a struct msg or struct avp.
+ *  dir         : Direction for browsing
+ *  found       : If not NULL, updated with the element that has been found, if any, or NULL if no element was found / an error occurred.
+ *  depth	: If not NULL, points to an integer representing the "depth" of this object in the tree. This is a relative value, updated on return.
+ *
+ * DESCRIPTION: 
+ *   Explore the content of a message object (hierarchy). If "found" is null, only error checking is performed.
+ *  If "depth" is provided, it is updated as follow on successful function return:
+ *   - not modified for MSG_BRW_NEXT and MSG_BRW_PREV.
+ *   - *depth = *depth + 1 for MSG_BRW_FIRST_CHILD and MSG_BRW_LAST_CHILD.
+ *   - *depth = *depth - 1 for MSG_BRW_PARENT.
+ *   - *depth = *depth + X for MSG_BRW_WALK, with X between 1 (returned the 1st child) and -N (returned the Nth parent's next).
+ *
+ * RETURN VALUE:
+ *  0      	: found has been updated (if non NULL).
+ *  EINVAL 	: A parameter is invalid.
+ *  ENOENT	: No element has been found where requested, and "found" was NULL (otherwise, *found is set to NULL and 0 is returned). 
+ */
+int fd_msg_browse_internal ( msg_or_avp * reference, enum msg_brw_dir dir, msg_or_avp ** found, int * depth );
+/* Macro to avoid having to cast the third parameter everywhere */
+#define fd_msg_browse( ref, dir, found, depth )	\
+	fd_msg_browse_internal( (ref), (dir), (void *)(found), (depth) )
+
+
+/*
+ * FUNCTION:	fd_msg_avp_add
+ *
+ * PARAMETERS:
+ *  reference 	: Pointer to a valid msg or avp.
+ *  dir         : location where the new AVP should be inserted, relative to the reference. MSG_BRW_PARENT and MSG_BRW_WALK are not valid.
+ *  avp         : pointer to the AVP object that must be inserted.
+ *
+ * DESCRIPTION: 
+ *   Adds an AVP into an object that can contain it: grouped AVP or message.
+ * Note that the added AVP will be freed at the same time as the object it is added to, 
+ * so it should not be freed after the call to this function.
+ *
+ * RETURN VALUE:
+ *  0      	: The AVP has been added.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_msg_avp_add ( msg_or_avp * reference, enum msg_brw_dir dir, struct avp *avp);
+
+/*
+ * FUNCTION:	fd_msg_search_avp
+ *
+ * PARAMETERS:
+ *  msg 	: The message structure in which to search the AVP.
+ *  what 	: The dictionary model of the AVP to search.
+ *  avp		: location where the AVP reference is stored if found.
+ *
+ * DESCRIPTION: 
+ *   Search the first top-level AVP of a given model inside a message.
+ * Note: only the first instance of the AVP is returned by this function.
+ * Note: only top-level AVPs are searched, not inside grouped AVPs.
+ * Use msg_browse if you need more advanced research features.
+ *
+ * RETURN VALUE:
+ *  0      	: The AVP has been found.
+ *  EINVAL 	: A parameter is invalid.
+ *  ENOENT	: No AVP has been found, and "avp" was NULL (otherwise, *avp is set to NULL and 0 returned).
+ */
+int fd_msg_search_avp ( struct msg * msg, struct dict_object * what, struct avp ** avp );
+
+/*
+ * FUNCTION:	fd_msg_free
+ *
+ * PARAMETERS:
+ *  object      : pointer to the message or AVP object that must be unlinked and freed.
+ *
+ * DESCRIPTION: 
+ *   Unlink and free a message or AVP object and its children.
+ *  If the object is an AVP linked into a message, the AVP is removed before being freed.
+ *
+ * RETURN VALUE:
+ *  0      	: The message has been freed.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_msg_free ( msg_or_avp * object );
+
+/***************************************/
+/*   Dump functions                    */
+/***************************************/
+/*
+ * FUNCTION:	fd_msg_dump_*
+ *
+ * PARAMETERS:
+ *  level	: the log level (INFO, FULL, ...) at which the object is dumped
+ *  obj		: A msg or avp object.
+ *
+ * DESCRIPTION: 
+ *   These functions dump the content of a message to the debug log
+ * either recursively or only the object itself.
+ *
+ * RETURN VALUE:
+ *   -
+ */
+void fd_msg_dump_walk ( int level, msg_or_avp *obj );
+void fd_msg_dump_one  ( int level, msg_or_avp *obj );
+
+
+/*********************************************/
+/*   Message metadata management functions   */
+/*********************************************/
+/*
+ * FUNCTION:	fd_msg_model
+ *
+ * PARAMETERS:
+ *  reference 	: Pointer to a valid msg or avp.
+ *  model       : on success, pointer to the dictionary model of this command or AVP. NULL if the model is unknown.
+ *
+ * DESCRIPTION: 
+ *   Retrieve the dictionary object describing this message or avp. If the object is unknown or the fd_msg_parse_dict has not been called,
+ *  *model is set to NULL.
+ *
+ * RETURN VALUE:
+ *  0      	: The model has been set.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_msg_model ( msg_or_avp * reference, struct dict_object ** model );
+
+/*
+ * FUNCTION:	fd_msg_hdr
+ *
+ * PARAMETERS:
+ *  msg 	: Pointer to a valid message object.
+ *  pdata 	: Upon success, pointer to the msg_hdr structure of this message. The fields may be modified.
+ *
+ * DESCRIPTION: 
+ *   Retrieve location of modifiable section of a message. 
+ *
+ * RETURN VALUE:
+ *  0      	: The location has been written.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_msg_hdr ( struct msg *msg, struct msg_hdr ** pdata );
+
+/*
+ * FUNCTION:	fd_msg_avp_hdr
+ *
+ * PARAMETERS:
+ *  avp 	: Pointer to a valid avp object.
+ *  pdata 	: Upon success, pointer to the avp_hdr structure of this avp. The fields may be modified.
+ *
+ * DESCRIPTION: 
+ *   Retrieve location of modifiable data of an avp. 
+ *
+ * RETURN VALUE:
+ *  0      	: The location has been written.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_msg_avp_hdr ( struct avp *avp, struct avp_hdr ** pdata );
+
+/*
+ * FUNCTION:	fd_msg_answ_associate, fd_msg_answ_getq, fd_msg_answ_detach
+ *
+ * PARAMETERS:
+ *  answer	: the received answer message
+ *  query	: the corresponding query that had been sent
+ *
+ * DESCRIPTION:
+ *  fd_msg_answ_associate associates a query msg with the received answer. 
+ * Query is retrieved with fd_msg_answ_getq.
+ * If answer message is freed, the query is also freed.
+ * If the msg_answ_detach function is called, the association is removed.
+ * This is meant to be called from the daemon only.
+ *
+ * RETURN VALUE:
+ *  0 	  : ok
+ *  EINVAL: a parameter is invalid
+ */
+int fd_msg_answ_associate( struct msg * answer, struct msg * query );
+int fd_msg_answ_getq     ( struct msg * answer, struct msg ** query );
+int fd_msg_answ_detach   ( struct msg * answer );
+
+/*
+ * FUNCTION:	fd_msg_anscb_associate, fd_msg_anscb_get
+ *
+ * PARAMETERS:
+ *  msg		: the answer message
+ *  anscb	: the callback to associate with the message
+ *  data	: the data to pass to the callback
+ *  timeout     : (optional, use NULL if no timeout) a timeout associated with calling the cb.
+ *
+ * DESCRIPTION:
+ *  Associate or retrieve a callback with an answer message.
+ * This is meant to be called from the daemon only.
+ *
+ * RETURN VALUE:
+ *  0 	  : ok
+ *  EINVAL: a parameter is invalid
+ */
+int fd_msg_anscb_associate( struct msg * msg, void ( *anscb)(void *, struct msg **), void  * data, const struct timespec *timeout );
+int fd_msg_anscb_get      ( struct msg * msg, void (**anscb)(void *, struct msg **), void ** data );
+struct timespec *fd_msg_anscb_gettimeout( struct msg * msg ); /* returns NULL or a valid non-0 timespec */
+
+/*
+ * FUNCTION:	fd_msg_rt_associate, fd_msg_rt_get
+ *
+ * PARAMETERS:
+ *  msg		: the query message to be sent
+ *  list	: the ordered list of possible next-peers
+ *
+ * DESCRIPTION:
+ *  Associate a routing list with a query, and retrieve it.
+ * If the message is freed, the list is also freed.
+ *
+ * RETURN VALUE:
+ *  0 	  : ok
+ *  EINVAL: a parameter is invalid
+ */
+int fd_msg_rt_associate( struct msg * msg, struct rt_data ** rtd );
+int fd_msg_rt_get      ( struct msg * msg, struct rt_data ** rtd );
+
+/*
+ * FUNCTION:	fd_msg_is_routable
+ *
+ * PARAMETERS:
+ *  msg		: A msg object.
+ *
+ * DESCRIPTION: 
+ *   This function returns a boolean telling if a given message is routable in the Diameter network, 
+ *  or if it is a local link message only (ex: CER/CEA, DWR/DWA, ...).
+ *
+ * RETURN VALUE:
+ *  0      	: The message is not routable / an error occurred.
+ *  1      	: The message is routable.
+ */
+int fd_msg_is_routable ( struct msg * msg );
+
+/*
+ * FUNCTION:	fd_msg_source_(g/s)et
+ *
+ * PARAMETERS:
+ *  msg		: A msg object.
+ *  diamid	: The diameter id of the peer from which this message was received.
+ *  add_rr	: if true, a Route-Record AVP is added to the message with content diamid. In that case, dict must be supplied.
+ *  dict	: a dictionary with definition of Route-Record AVP (if add_rr is true)
+ *
+ * DESCRIPTION: 
+ *   Store or retrieve the diameted id of the peer from which this message was received.
+ * Will be used for example by the routing module to add the Route-Record AVP in forwarded requests,
+ * or to direct answers to the appropriate peer.
+ *
+ * RETURN VALUE:
+ *  0      	: Operation complete.
+ *  !0      	: an error occurred.
+ */
+int fd_msg_source_set( struct msg * msg, char * diamid, int add_rr, struct dictionary * dict );
+int fd_msg_source_get( struct msg * msg, char ** diamid );
+
+/*
+ * FUNCTION:	fd_msg_eteid_get
+ *
+ * PARAMETERS:
+ *  -
+ *
+ * DESCRIPTION: 
+ *   Get a new unique end-to-end id value for the local peer.
+ *
+ * RETURN VALUE:
+ *  The new assigned value. No error code is defined.
+ */
+uint32_t fd_msg_eteid_get ( void );
+
+
+/*
+ * FUNCTION:	fd_msg_sess_get
+ *
+ * PARAMETERS:
+ *  dict	: the dictionary that contains the Session-Id AVP definition
+ *  msg		: A valid message.
+ *  session	: Location to store the session pointer when retrieved.
+ *  isnew	: Indicates if the session has been created.
+ *
+ * DESCRIPTION:
+ *  This function retrieves or creates the session object corresponding to a message.
+ * If the message does not contain a Session-Id AVP, *session == NULL on return.
+ * Note that the Session-Id AVP must never be modified after created in a message.
+ *
+ * RETURN VALUE:
+ *  0 : success
+ * !0 : standard error code.
+ */
+int fd_msg_sess_get(struct dictionary * dict, struct msg * msg, struct session ** session, int * isnew);
+
+/***************************************/
+/*   Manage AVP values                 */
+/***************************************/
+
+/*
+ * FUNCTION:	fd_msg_avp_setvalue
+ *
+ * PARAMETERS:
+ *  avp 	: Pointer to a valid avp object with a NULL avp_value pointer. The model must be known.
+ *  value 	: pointer to an avp_value. The content will be COPIED into the internal storage area. 
+ *		 If data type is an octetstring, the data is also copied.
+ * 		 If value is a NULL pointer, the previous data is erased and value is unset in the AVP.
+ *
+ * DESCRIPTION: 
+ *   Initialize the avp_value field of an AVP header.
+ *
+ * RETURN VALUE:
+ *  0      	: The avp_value pointer has been set.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_msg_avp_setvalue ( struct avp *avp, union avp_value *value );
+
+/*
+ * FUNCTION:	fd_msg_avp_value_encode
+ *
+ * PARAMETERS:
+ *  avp 	: Pointer to a valid avp object with a NULL avp_value. The model must be known.
+ *  data 	: Pointer to the data that must be encoded as AVP value and stored in the AVP.
+ *		 This is only valid for AVPs of derived type for which type_data_encode callback is set. (ex: Address type)
+ *
+ * DESCRIPTION: 
+ *   Initialize the avp_value field of an AVP object from formatted data, using the AVP's type "type_data_encode" callback.
+ *
+ * RETURN VALUE:
+ *  0      	: The avp_value has been set.
+ *  EINVAL 	: A parameter is invalid.
+ *  ENOTSUP 	: There is no appropriate callback registered with this AVP's type.
+ */
+int fd_msg_avp_value_encode ( void *data, struct avp *avp );
+/*
+ * FUNCTION:	fd_msg_avp_value_interpret
+ *
+ * PARAMETERS:
+ *  avp 	: Pointer to a valid avp object with a non-NULL avp_value value.
+ *  data 	: Upon success, formatted interpretation of the AVP value is stored here.
+ *
+ * DESCRIPTION: 
+ *   Interpret the content of an AVP of Derived type and store the result in data pointer. The structure
+ * of the data pointer is dependent on the AVP type. This function calls the "type_data_interpret" callback 
+ * of the type.
+ *
+ * RETURN VALUE:
+ *  0      	: The avp_value has been set.
+ *  EINVAL 	: A parameter is invalid.
+ *  ENOTSUP 	: There is no appropriate callback registered with this AVP's type.
+ */
+int fd_msg_avp_value_interpret ( struct avp *avp, void *data );
+
+
+/***************************************/
+/*   Message parsing functions         */
+/***************************************/
+
+/*
+ * FUNCTION:	fd_msg_bufferize
+ *
+ * PARAMETERS:
+ *  msg		: A valid msg object. All AVPs must have a value set. 
+ *  buffer 	: Upon success, this points to a buffer (malloc'd) containing the message ready for network transmission (or security transformations). 
+ *		 The buffer may be freed after use.
+ *  len		: if not NULL, the size of the buffer is written here. In any case, this size is updated in the msg header.
+ *
+ * DESCRIPTION: 
+ *   Renders a message in memory as a buffer that can be sent over the network to the next peer.
+ *
+ * RETURN VALUE:
+ *  0      	: The location has been written.
+ *  EINVAL 	: The buffer does not contain a valid Diameter message.
+ *  ENOMEM	: Unable to allocate enough memory to create the buffer object.
+ */
+int fd_msg_bufferize ( struct msg * msg, unsigned char ** buffer, size_t * len );
+
+/*
+ * FUNCTION:	fd_msg_parse_buffer
+ *
+ * PARAMETERS:
+ *  buffer 	: Pointer to a buffer containing a message received from the network. 
+ *  buflen	: the size in bytes of the buffer.
+ *  msg		: Upon success, this points to a valid msg object. No AVP value is resolved in this object, nor grouped AVP.
+ *
+ * DESCRIPTION: 
+ *   This function parses a buffer an creates a msg object to represent the structure of the message.
+ *  Since no dictionary lookup is performed, the values of the AVPs are not interpreted. To interpret the values,
+ *  the returned message object must be passed to fd_msg_parse_dict function.
+ *  The buffer pointer is saved inside the message and will be freed when not needed anymore.
+ *
+ * RETURN VALUE:
+ *  0      	: The location has been written.
+ *  ENOMEM	: Unable to allocate enough memory to create the msg object.
+ *  EBADMSG	: The buffer does not contain a valid Diameter message (or is truncated).
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_msg_parse_buffer ( unsigned char ** buffer, size_t buflen, struct msg ** msg );
+
+/* Parsing Error Information structure */
+struct fd_pei {
+	char *		pei_errcode;	/* name of the error code to use */
+	struct avp *	pei_avp;	/* pointer to invalid or missing AVP (to be freed) */
+	char *		pei_message;	/* Overwrite default message if needed */
+	int		pei_protoerr; 	/* do we set the 'E' bit in the error message ? */
+};
+
+/*
+ * FUNCTION:	fd_msg_parse_dict
+ *
+ * PARAMETERS:
+ *  object	: A msg or AVP object as returned by fd_msg_parse_buffer.
+ *  dict	: the dictionary containing the objects definitions to use for resolving all AVPs.
+ *  error_info	: If not NULL, will contain the detail about error upon return. May be used to generate an error reply.
+ *
+ * DESCRIPTION: 
+ *   This function looks up for the command and each children AVP definitions in the dictionary.
+ *  If the dictionary definition is found, avp_model is set and the value of the AVP is interpreted accordingly and:
+ *   - for grouped AVPs, the children AVP are created and interpreted also.
+ *   - for numerical AVPs, the value is converted to host byte order and saved in the avp_value field.
+ *   - for octetstring AVPs, the string is copied into a new buffer and its address is saved in avp_value. 
+ *  If the dictionary definition is not found, avp_model is set to NULL and
+ *  the content of the AVP is saved as an octetstring in an internal structure. avp_value is NULL.
+ *  As a result, after this function has been called, there is no more dependency of the msg object to the message buffer, that is freed.
+ *
+ * RETURN VALUE:
+ *  0      	: The message has been fully parsed as described.
+ *  EINVAL 	: The msg parameter is invalid for this operation.
+ *  ENOMEM	: Unable to allocate enough memory to complete the operation.
+ *  ENOTSUP	: No dictionary definition for the command or one of the mandatory AVP was found.
+ */
+int fd_msg_parse_dict ( msg_or_avp * object, struct dictionary * dict, struct fd_pei * error_info );
+
+/*
+ * FUNCTION:	fd_msg_parse_rules
+ *
+ * PARAMETERS:
+ *  object	: A msg or grouped avp object that must be verified.
+ *  dict	: The dictionary containing the rules definitions.
+ *  error_info	: If not NULL, the first problem information will be saved here.
+ *
+ * DESCRIPTION: 
+ *   Check that the children of the object do not conflict with the dictionary rules (ABNF compliance).
+ *
+ * RETURN VALUE:
+ *  0      	: The message has been fully parsed and complies to the defined rules.
+ *  EBADMSG	: A conflict was detected, or a mandatory AVP is unknown in the dictionary.
+ *  EINVAL 	: The msg or avp object is invalid for this operation.
+ *  ENOMEM	: Unable to allocate enough memory to complete the operation.
+ */
+int fd_msg_parse_rules ( msg_or_avp * object, struct dictionary * dict, struct fd_pei * error_info);
+
+
+
+/*
+ * FUNCTION:	fd_msg_update_length
+ *
+ * PARAMETERS:
+ *  object 	: Pointer to a valid msg or avp. 
+ *
+ * DESCRIPTION: 
+ *   Update the length field of the object passed as parameter.
+ * As a side effect, all children objects are also updated. Therefore, all avp_value fields of
+ * the children AVPs must be set, or an error will occur.
+ *
+ * RETURN VALUE:
+ *  0      	: The size has been recomputed.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_msg_update_length ( msg_or_avp * object );
+
+
+/*============================================================*/
+/*                         DISPATCH                           */
+/*============================================================*/
+
+/* Dispatch module (passing incoming messages to extensions registered callbacks)
+ * is split between the library and the daemon.
+ *
+ * The library provides the support for associating dispatch callbacks with
+ * dictionary objects.
+ *
+ * The daemon is responsible for calling the callbacks for a message when appropriate.
+ *
+ *
+ * The dispatch module has two main roles:
+ *  - help determine if a message can be handled locally (during the routing step)
+ *        This decision involves only the application-id of the message.
+ *  - pass the message to the callback(s) that will handle it (during the dispatch step)
+ *
+ * The first role is handled by the daemon.
+ *
+ * About the second, these are the possibilities for registering a dispatch callback:
+ *
+ * -> For All messages.
+ *  This callback is called for all messages that are handled locally. This should be used only
+ *  for debug purpose.
+ *
+ * -> by AVP value (constants only).
+ *  This callback will be called when a message is received and contains an AVP with a specified enumerated value.
+ *
+ * -> by AVP.
+ *  This callback will be called when the received message contains a certain AVP.
+ *
+ * -> by command-code.
+ *  This callback will be called when the message is a specific command (and 'R' flag).
+ *
+ * -> by application.
+ *  This callback will be called when the message has a specific application-id.
+ *
+ * ( by vendor: would this be useful? it may be added later)
+ */
+enum disp_how {
+	DISP_HOW_ANY = 1,		/* Any message. This should be only used for debug. */
+	DISP_HOW_APPID,			/* Any message with the specified application-id */
+	DISP_HOW_CC,			/* Messages of the specified command-code (request or answer). App id may be specified. */
+	DISP_HOW_AVP,			/* Messages containing a specific AVP. Command-code and App id may be specified. */
+	DISP_HOW_AVP_ENUMVAL		/* Messages containing a specific AVP with a specific enumerated value. Command-code and App id may be specified. */
+};
+/*
+ * Several criteria may be selected at the same time, for example command-code AND application id.
+ *
+ * If several callbacks are registered for the same object, they are called in the order they were registered.
+ * The order in which the callbacks are called is:
+ *  DISP_HOW_ANY
+ *  DISP_HOW_AVP_ENUMVAL & DISP_HOW_AVP
+ *  DISP_HOW_CC
+ *  DISP_HOW_APPID
+ */
+
+/* When a callback is registered, a "when" argument is passed in addition to the disp_how value,
+ * to specify which values the criteria must match. */
+struct disp_when {
+	struct dict_object *	app;
+	struct dict_object *	command;
+	struct dict_object *	avp;
+	struct dict_object *	value;
+};
+
+/* Note that all the dictionary objects should really belong to the same dictionary!
+ *
+ * Here is the details on this "when" argument, depending on the disp_how value.
+ *
+ * DISP_HOW_ANY.
+ *  In this case, "when" must be NULL.
+ *
+ * DISP_HOW_APPID.
+ *  Only the "app_id" field must be set, other fields are ignored. It points to a dictionary object of type DICT_APPLICATION.
+ *
+ * DISP_HOW_CC.
+ *  The "command" field must be defined and point to a dictionary object of type DICT_COMMAND.
+ *  The "app_id" may be also set. In the case it is set, it restricts the callback to be called only with this command-code and app id.
+ *  The other fields are ignored.
+ *
+ * DISP_HOW_AVP.
+ *  The "avp" field of the structure must be set and point to a dictionary object of type DICT_AVP.
+ *  The "app_id" field may be set to restrict the messages matching to a specific app id.
+ *  The "command" field may also be set to a valid DICT_COMMAND object.
+ *  The content of the "value" field is ignored.
+ *
+ * DISP_HOW_AVP_ENUMVAL.
+ *  All fields have the same constraints and meaning as in DISP_REG_AVP. In addition, the "value" field must be set
+ *  and points to a valid DICT_ENUMVAL object. 
+ *
+ * Here is a sumary of the fields: ( M : must be set; m : may be set; 0 : ignored )
+ *  field:     app_id    command     avp    value
+ * APPID :       M          0         0       0
+ * CC    :       m          M         0       0
+ * AVP   :       m          m         M       0
+ * ENUMVA:       m          m         M       M
+ */
+
+enum disp_action {
+	DISP_ACT_CONT,	/* The next handler should be called, unless *msg == NULL. */
+	DISP_ACT_SEND,	/* The updated message must be sent. No further callback is called. */
+	DISP_ACT_ERROR	/* An error must be created and sent as a reply -- not valid for callbacks, only for fd_msg_dispatch. */
+};
+/* The callbacks that are registered have the following prototype:
+ *  	int dispatch_callback( struct msg ** msg, struct avp * avp, struct session * session, enum disp_action * action );
+ *
+ * CALLBACK:	dispatch_callback
+ *
+ * PARAMETERS:
+ *  msg 	: the received message on function entry. may be updated to answer on return (see description)
+ *  avp 	: for callbacks registered with DISP_HOW_AVP or DISP_HOW_AVP_ENUMVAL, direct link to the triggering AVP.
+ *  session	: if the message contains a Session-Id AVP, the corresponding session object, NULL otherwise.
+ *  opaque      : An opaque pointer that is registered along the session handler.
+ *  action	: upon return, this tells the daemon what to do next.
+ *
+ * DESCRIPTION: 
+ *   Called when a received message matchs the condition for which the callback was registered.
+ * This callback may do any kind of processing on the message, including:
+ *  - create an answer for a request.
+ *  - proxy a request or message, add / remove the Proxy-Info AVP, then forward the message.
+ *  - update a routing table or start a connection with a new peer, then forward the message.
+ *  - ...
+ * 
+ * When *action == DISP_ACT_SEND on callback return, the msg pointed by *msg is passed to the routing module for sending.
+ * When *action == DISP_ACT_CONT, the next registered callback is called.
+ *  When the last callback gives also DISP_ACT_CONT action value, a default handler is called. It's behavior is as follow:
+ *   - if the message is an answer, it is discarded.
+ *   - if the message is a request, it is passed again to the routing stack, and marked as non-local handling.
+ *
+ * RETURN VALUE:
+ *  0      	: The callback executed successfully and updated *action appropriately.
+ *  !0		: standard errors. In case of error, the message is discarded.
+ */
+
+/* This structure represents a handler for a registered callback, allowing its de-registration */
+struct disp_hdl;
+
+/*
+ * FUNCTION:	fd_disp_register
+ *
+ * PARAMETERS:
+ *  cb 		  : The callback function to register (see dispatch_callback description above).
+ *  how	  	  : How the callback must be registered.
+ *  when          : Values that must match, depending on the how argument.
+ *  opaque        : A pointer that is passed back to the handler. The content is not interpreted by the framework.
+ *  handle        : On success, a handler to the registered callback is stored here if not NULL. 
+ *		   This handler can be used to unregister the cb.
+ *
+ * DESCRIPTION: 
+ *   Register a new callback to handle messages delivered locally.
+ *
+ * RETURN VALUE:
+ *  0      	: The callback is registered.
+ *  EINVAL 	: A parameter is invalid.
+ *  ENOMEM	: Not enough memory to complete the operation
+ */
+int fd_disp_register ( int (*cb)( struct msg **, struct avp *, struct session *, void *, enum disp_action *), 
+			enum disp_how how, struct disp_when * when, void * opaque, struct disp_hdl ** handle );
+
+/*
+ * FUNCTION:	fd_disp_unregister
+ *
+ * PARAMETERS:
+ *  handle       : Location of the handle of the callback that must be unregistered.
+ *  opaque       : If not NULL, the opaque data that was registered is restored here.
+ *
+ * DESCRIPTION: 
+ *   Removes a callback previously registered by fd_disp_register.
+ *
+ * RETURN VALUE:
+ *  0      	: The callback is unregistered.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_disp_unregister ( struct disp_hdl ** handle, void ** opaque );
+
+/* Destroy all handlers */
+void fd_disp_unregister_all ( void );
+
+/*
+ * FUNCTION:	fd_msg_dispatch
+ *
+ * PARAMETERS:
+ *  msg 	: A msg object that have already been fd_msg_parse_dict.
+ *  session	: The session corresponding to this object, if any.
+ *  action	: Upon return, the action that must be taken on the message
+ *
+ * DESCRIPTION: 
+ *   Call all handlers registered for a given message.
+ *  The session must have already been resolved on entry.
+ *  The msg pointed may be updated during this process.
+ *  Upon return, the action parameter points to what must be done next.
+ *
+ * RETURN VALUE:
+ *  0      	: Success.
+ *  EINVAL 	: A parameter is invalid.
+ *  (other errors)
+ */
+int fd_msg_dispatch ( struct msg ** msg, struct session * session, enum disp_action *action, const char ** error_code );
+
+
+
+/*============================================================*/
+/*                     QUEUES                                 */
+/*============================================================*/
+
+/* Management of FIFO queues of elements */
+
+/* A queue is an opaque object */
+struct fifo;
+
+/*
+ * FUNCTION:	fd_fifo_new
+ *
+ * PARAMETERS:
+ *  queue	: Upon success, a pointer to the new queue is saved here.
+ *
+ * DESCRIPTION: 
+ *  Create a new empty queue.
+ *
+ * RETURN VALUE :
+ *  0		: The queue has been initialized successfully.
+ *  EINVAL 	: The parameter is invalid.
+ *  ENOMEM	: Not enough memory to complete the creation.  
+ */
+int fd_fifo_new ( struct fifo ** queue );
+
+/*
+ * FUNCTION:	fd_fifo_del
+ *
+ * PARAMETERS:
+ *  queue	: Pointer to an empty queue to delete.
+ *
+ * DESCRIPTION: 
+ *  Destroys a queue. This is only possible if no thread is waiting for an element,
+ * and the queue is empty.
+ *
+ * RETURN VALUE:
+ *  0		: The queue has been destroyed successfully.
+ *  EINVAL 	: The parameter is invalid.
+ */
+int fd_fifo_del ( struct fifo  ** queue );
+
+/*
+ * FUNCTION:	fd_fifo_move
+ *
+ * PARAMETERS:
+ *  oldq	: Location of a FIFO that is to be emptied.
+ *  newq	: A FIFO that will receive the old data.
+ *  loc_update	: if non NULL, a place to store the pointer to new FIFO atomically with the move.
+ *
+ * DESCRIPTION: 
+ *  Empties a queue and move its content to another one atomically.
+ *
+ * RETURN VALUE:
+ *  0		: The queue has been destroyed successfully.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_fifo_move ( struct fifo * oldq, struct fifo * newq, struct fifo ** loc_update );
+
+/*
+ * FUNCTION:	fd_fifo_length
+ *
+ * PARAMETERS:
+ *  queue	: The queue from which to retrieve the number of elements.
+ *  length	: Upon success, the current number of elements in the queue is stored here.
+ *
+ * DESCRIPTION: 
+ *  Retrieve the number of elements in a queue.
+ *
+ * RETURN VALUE:
+ *  0		: The length of the queue has been written.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_fifo_length ( struct fifo * queue, int * length );
+int fd_fifo_length_noerr ( struct fifo * queue ); /* no error checking version */
+
+/*
+ * FUNCTION:	fd_fifo_setthrhd
+ *
+ * PARAMETERS:
+ *  queue	: The queue for which the thresholds are being set.
+ *  data	: An opaque pointer that is passed to h_cb and l_cb callbacks.
+ *  high        : The high-level threshold. If the number of elements in the queue increase to this value, h_cb is called.
+ *  h_cb        : if not NULL, a callback to call when the queue lengh is bigger than "high".
+ *  low         : The low-level threshold. Must be < high.
+ *  l_cb        : If the number of elements decrease to low, this callback is called.
+ *
+ * DESCRIPTION: 
+ *  This function allows to adjust the number of producer / consumer threads of a queue.
+ * If the consumer are slower than the producers, the number of elements in the queue increase.
+ * By setting a "high" value, we allow a callback to be called when this number is too high.
+ * The typical use would be to create an additional consumer thread in this callback.
+ * If the queue continues to grow, the callback will be called again when the length is 2 * high, then 3*high, ... N * high
+ * (the callback itself should implement a limit on the number of consumers that can be created)
+ * When the queue starts to decrease, and the number of elements go under ((N - 1) * high + low, the l_cb callback is called
+ * and would typially stop one of the consumer threads. If the queue continues to reduce, l_cb is again called at (N-2)*high + low,
+ * and so on.
+ *
+ * Since there is no destructor for the data pointer, if cleanup operations are required, they should be performed in
+ * l_cb when the length of the queue is becoming < low.
+ *
+ * Note that the callbacks are called synchronously, during fd_fifo_post or fd_fifo_get. Their operation should be quick.
+ *
+ * RETURN VALUE:
+ *  0		: The thresholds have been set
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_fifo_setthrhd ( struct fifo * queue, void * data, uint16_t high, void (*h_cb)(struct fifo *, void **), uint16_t low, void (*l_cb)(struct fifo *, void **) );
+
+/*
+ * FUNCTION:	fd_fifo_post
+ *
+ * PARAMETERS:
+ *  queue	: The queue in which the element must be posted.
+ *  item	: The element that is put in the queue.
+ *
+ * DESCRIPTION: 
+ *  An element is added in a queue. Elements are retrieved from the queue in FIFO order
+ *  with the fd_fifo_get, fd_fifo_tryget, or fd_fifo_timedget functions.
+ *
+ * RETURN VALUE:
+ *  0		: The element is queued.
+ *  EINVAL 	: A parameter is invalid.
+ *  ENOMEM 	: Not enough memory to complete the operation.
+ */
+int fd_fifo_post_int ( struct fifo * queue, void ** item );
+#define fd_fifo_post(queue, item) \
+	fd_fifo_post_int((queue), (void *)(item))
+
+/*
+ * FUNCTION:	fd_fifo_get
+ *
+ * PARAMETERS:
+ *  queue	: The queue from which the first element must be retrieved.
+ *  item	: On return, the first element of the queue is stored here.
+ *
+ * DESCRIPTION: 
+ *  This function retrieves the first element from a queue. If the queue is empty, the function will block the 
+ * thread until a new element is posted to the queue, or until the thread is canceled (in which case the 
+ * function does not return).
+ *
+ * RETURN VALUE:
+ *  0		: A new element has been retrieved.
+ *  EINVAL 	: A parameter is invalid.
+ */
+int fd_fifo_get_int ( struct fifo * queue, void ** item );
+#define fd_fifo_get(queue, item) \
+	fd_fifo_get_int((queue), (void *)(item))
+
+/*
+ * FUNCTION:	fd_fifo_tryget
+ *
+ * PARAMETERS:
+ *  queue	: The queue from which the element must be retrieved.
+ *  item	: On return, the first element of the queue is stored here.
+ *
+ * DESCRIPTION: 
+ *  This function is similar to fd_fifo_get, except that it will not block if 
+ * the queue is empty, but return EWOULDBLOCK instead.
+ *
+ * RETURN VALUE:
+ *  0		: A new element has been retrieved.
+ *  EINVAL 	: A parameter is invalid.
+ *  EWOULDBLOCK : The queue was empty.
+ */
+int fd_fifo_tryget_int ( struct fifo * queue, void ** item );
+#define fd_fifo_tryget(queue, item) \
+	fd_fifo_tryget_int((queue), (void *)(item))
+
+/*
+ * FUNCTION:	fd_fifo_timedget
+ *
+ * PARAMETERS:
+ *  queue	: The queue from which the element must be retrieved.
+ *  item	: On return, the element is stored here.
+ *  abstime	: the absolute time until which we allow waiting for an item.
+ *
+ * DESCRIPTION: 
+ *  This function is similar to fd_fifo_get, except that it will block if the queue is empty 
+ * only until the absolute time abstime (see pthread_cond_timedwait for + info).
+ * If the queue is still empty when the time expires, the function returns ETIMEDOUT
+ *
+ * RETURN VALUE:
+ *  0		: A new item has been retrieved.
+ *  EINVAL 	: A parameter is invalid.
+ *  ETIMEDOUT   : The time out has passed and no item has been received.
+ */
+int fd_fifo_timedget_int ( struct fifo * queue, void ** item, const struct timespec *abstime );
+#define fd_fifo_timedget(queue, item, abstime) \
+	fd_fifo_timedget_int((queue), (void *)(item), (abstime))
+
+/* Dump a fifo list and optionally its inner elements -- beware of deadlocks! */
+void fd_fifo_dump(int level, char * name, struct fifo * queue, void (*dump_item)(int level, void * item));
+
+#endif /* _LIBFDPROTO_H */
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