Systemd/src/libsystemd-bus/bus-message.h

/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/

#pragma once

/***
  This file is part of systemd.

  Copyright 2013 Lennart Poettering

  systemd is free software; you can redistribute it and/or modify it
  under the terms of the GNU Lesser General Public License as published by
  the Free Software Foundation; either version 2.1 of the License, or
  (at your option) any later version.

  systemd is distributed in the hope that it will be useful, but
  WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public License
  along with systemd; If not, see <http://www.gnu.org/licenses/>.
***/

#include <stdbool.h>
#include <byteswap.h>

#include "macro.h"
#include "sd-bus.h"

struct bus_container {
        char enclosing;

        char *signature;
        unsigned index;

        uint32_t *array_size;
};

_packed_ struct bus_header {
        uint8_t endian;
        uint8_t type;
        uint8_t flags;
        uint8_t version;
        uint32_t body_size;
        uint32_t serial;
        uint32_t fields_size;
};

struct sd_bus_message {
        unsigned n_ref;

        uint32_t reply_serial;

        const char *path;
        const char *interface;
        const char *member;
        const char *destination;
        const char *sender;
        const char *signature;

        sd_bus_error error;

        uid_t uid;
        gid_t gid;
        pid_t pid;
        pid_t tid;

        bool sealed:1;
        bool uid_valid:1;
        bool gid_valid:1;
        bool free_header:1;
        bool free_fields:1;
        bool free_body:1;
        bool dont_send:1;

        struct bus_header *header;
        void *fields;
        void *body;

        uint32_t n_fds;
        int *fds;

        struct bus_container root_container, *sub_containers;
        unsigned n_containers;

        struct iovec iovec[4];
        unsigned n_iovec;
};

#if __BYTE_ORDER == __BIG_ENDIAN
#define BUS_MESSAGE_NEED_BSWAP(m) ((m)->header->endian != SD_BUS_BIG_ENDIAN)
#else
#define BUS_MESSAGE_NEED_BSWAP(m) ((m)->header->endian != SD_BUS_LITTLE_ENDIAN)
#endif

static inline uint32_t BUS_MESSAGE_BSWAP(sd_bus_message *m, uint32_t u) {
        return BUS_MESSAGE_NEED_BSWAP(m) ? bswap_32(u) : u;
}

static inline uint32_t BUS_MESSAGE_SERIAL(sd_bus_message *m) {
        return BUS_MESSAGE_BSWAP(m, m->header->serial);
}

static inline uint32_t BUS_MESSAGE_BODY_SIZE(sd_bus_message *m) {
        return BUS_MESSAGE_BSWAP(m, m->header->body_size);
}

static inline uint32_t BUS_MESSAGE_FIELDS_SIZE(sd_bus_message *m) {
        return BUS_MESSAGE_BSWAP(m, m->header->fields_size);
}

static inline void bus_message_unrefp(sd_bus_message **m) {
        sd_bus_message_unref(*m);
}

#define _cleanup_bus_message_unref_ __attribute__((cleanup(bus_message_unrefp)))

int message_parse(sd_bus_message *m);
int message_seal(sd_bus_message *m, uint64_t serial);
void message_dump(sd_bus_message *m);
int bus_message_get_blob(sd_bus_message *m, void **buffer, size_t *sz);