source: vendor/current/ctdb/common/pkt_write.c

/*
   Write a packet

   Copyright (C) Amitay Isaacs 2015

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program 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 General Public License for more details.

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

#include "replace.h"
#include "system/network.h"

#include <talloc.h>
#include <tevent.h>

#include "lib/util/tevent_unix.h"

#include "pkt_write.h"

/*
 * Write a packet
 */

struct pkt_write_state {
        int fd;
        uint8_t *buf;
        size_t buflen, offset;
};

struct tevent_req *pkt_write_send(TALLOC_CTX *mem_ctx,
                                  struct tevent_context *ev,
                                  int fd, uint8_t *buf, size_t buflen)
{
        struct tevent_req *req;
        struct pkt_write_state *state;

        req = tevent_req_create(mem_ctx, &state, struct pkt_write_state);
        if (req == NULL) {
                return NULL;
        }

        state->fd = fd;
        state->buf = buf;
        state->buflen = buflen;
        state->offset = 0;

        return req;
}

void pkt_write_handler(struct tevent_context *ev, struct tevent_fd *fde,
                       uint16_t flags, struct tevent_req *req)
{
        struct pkt_write_state *state = tevent_req_data(
                req, struct pkt_write_state);
        ssize_t nwritten;

        nwritten = write(state->fd, state->buf + state->offset,
                         state->buflen - state->offset);
        if ((nwritten == -1) && (errno == EINTR)) {
                /* retry */
                return;
        }
        if (nwritten == -1) {
                tevent_req_error(req, errno);
                return;
        }
        if (nwritten == 0) {
                /* retry */
                return;
        }

        state->offset += nwritten;
        if (state->offset < state->buflen) {
                /* come back later */
                return;
        }

        tevent_req_done(req);
}

ssize_t pkt_write_recv(struct tevent_req *req, int *perrno)
{
        struct pkt_write_state *state = tevent_req_data(
                req, struct pkt_write_state);

        if (tevent_req_is_unix_error(req, perrno)) {
                return -1;
        }

        return state->offset;
}