/* -*- mode: c; c-file-style: "openbsd" -*- */
/*
* Copyright (c) 2012 Vincent Bernat <bernat@luffy.cx>
*
* Permission to use, copy, modify, and/or distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#ifndef _MARSHAL_H
#define _MARSHAL_H
#include <stddef.h>
#include <sys/types.h>
struct marshal_info;
enum marshal_subinfo_kind {
pointer,
substruct,
ignore,
};
#define MARSHAL_INFO_POINTER 1
#define MARSHAL_INFO_SUB 2
struct marshal_subinfo {
size_t offset; /* Offset compared to parent structure */
size_t offset2; /* Ancillary offset (for related data) */
enum marshal_subinfo_kind kind; /* Kind of substructure */
struct marshal_info *mi;
};
#define MARSHAL_SUBINFO_NULL { .offset = 0, .offset2 = 0, .kind = ignore, .mi = NULL }
struct marshal_info {
char *name; /* Name of structure */
size_t size; /* Size of the structure */
#if defined __GNUC__ && __GNUC__ < 3
/* With gcc 2.96, flexible arrays are not supported, even with
* -std=gnu99. And with gcc 3.x, zero-sized arrays cannot be statically
* initialized (with more than one element). */
struct marshal_subinfo pointers[0]; /* Pointer to other structures */
#else
struct marshal_subinfo pointers[]; /* Pointer to other structures */
#endif
};
/* Special case for strings */
extern struct marshal_info marshal_info_string;
extern struct marshal_info marshal_info_fstring;
extern struct marshal_info marshal_info_ignore;
/* Declare a new marshal_info struct named after the type we want to
marshal. The marshalled type has to be a structure. */
#define MARSHAL_INFO(type) marshal_info_##type
#ifdef MARSHAL_EXPORT
#define MARSHAL_HELPER_FUNCTIONS(type, ttype) \
ssize_t \
type ## _serialize(ttype *source, void *buffer) { \
return marshal_serialize(type, \
source, buffer); \
} \
size_t \
type ## _unserialize(void *buffer, size_t len, \
ttype **destination) { \
void *p; \
size_t rc; \
rc = marshal_unserialize(type, \
buffer, len, &p); \
if (rc <= 0) return rc; \
*destination = p; \
return rc; \
}
#define MARSHAL_BEGIN(type) struct marshal_info MARSHAL_INFO(type) = \
{ \
.name = #type, \
.size = sizeof(struct type), \
.pointers = {
#define MARSHAL_ADD(_kind, type, subtype, member) \
{ .offset = offsetof(struct type, member), \
.offset2 = 0, \
.kind = _kind, \
.mi = &MARSHAL_INFO(subtype) },
#define MARSHAL_FSTR(type, member, len) \
{ .offset = offsetof(struct type, member), \
.offset2 = offsetof(struct type, len), \
.kind = pointer, \
.mi = &marshal_info_fstring },
#define MARSHAL_END(type) MARSHAL_SUBINFO_NULL }}; \
MARSHAL_HELPER_FUNCTIONS(type, struct type)
#else
#define MARSHAL_HELPER_FUNCTIONS(type, ttype) \
ssize_t type ## _serialize(ttype*, void*); \
size_t type ## _unserialize(void*, size_t, ttype**);
#define MARSHAL_BEGIN(type) extern struct marshal_info MARSHAL_INFO(type);
#define MARSHAL_ADD(...)
#define MARSHAL_FSTR(...)
#define MARSHAL_END(type) MARSHAL_HELPER_FUNCTIONS(type, struct type)
#endif
/* Shortcuts */
#define MARSHAL_POINTER(...) MARSHAL_ADD(pointer, ##__VA_ARGS__)
#define MARSHAL_SUBSTRUCT(...) MARSHAL_ADD(substruct, ##__VA_ARGS__)
#define MARSHAL_STR(type, member) MARSHAL_ADD(pointer, type, string, member)
#define MARSHAL_IGNORE(type, member) MARSHAL_ADD(ignore, type, ignore, member)
#define MARSHAL_TQE(type, field) \
MARSHAL_POINTER(type, type, field.tqe_next) \
MARSHAL_IGNORE(type, field.tqe_prev)
/* Support for TAILQ list is partial. Access to last and previous
elements is not available. Some operations are therefore not
possible. However, TAILQ_FOREACH is still
available. */
#define MARSHAL_TQH(type, subtype) \
MARSHAL_POINTER(type, subtype, tqh_first) \
MARSHAL_IGNORE(type, tqh_last)
#define MARSHAL_SUBTQ(type, subtype, field) \
MARSHAL_POINTER(type, subtype, field.tqh_first) \
MARSHAL_IGNORE(type, field.tqh_last)
#define MARSHAL(type) \
MARSHAL_BEGIN(type) \
MARSHAL_END(type)
#define MARSHAL_TQ(type, subtype) \
MARSHAL_BEGIN(type) \
MARSHAL_TQH(type, subtype) \
MARSHAL_END(type)
/* Serialization */
ssize_t marshal_serialize_(struct marshal_info *, void *, void **, int, void *, int)
__attribute__((nonnull (1, 2, 3) ));
#define marshal_serialize(type, o, output) marshal_serialize_(&MARSHAL_INFO(type), o, output, 0, NULL, 0)
/* Unserialization */
size_t marshal_unserialize_(struct marshal_info *, void *, size_t, void **, void*, int, int)
__attribute__((nonnull (1, 2, 4) ));
#define marshal_unserialize(type, o, l, input) \
marshal_unserialize_(&MARSHAL_INFO(type), o, l, input, NULL, 0, 0)
#define marshal_repair_tailq(type, head, field) \
do { \
struct type *__item, *__item_next; \
(head)->tqh_last = &(head)->tqh_first; \
for (__item = TAILQ_FIRST(head); \
__item != NULL; \
__item = __item_next) { \
__item_next = TAILQ_NEXT(__item, field); \
__item->field.tqe_prev = (head)->tqh_last; \
*(head)->tqh_last = __item; \
(head)->tqh_last = &__item->field.tqe_next; \
} \
} while(0)
#endif