src/lib/write-full.c

/* Copyright (c) 2002-2018 Dovecot authors, see the included COPYING file */

#include "lib.h"
#include "write-full.h"

#include <unistd.h>

int write_full(int fd, const void *data, size_t size)
{
    ssize_t ret;

    while (size > 0) {
        ret = write(fd, data, size < SSIZE_T_MAX ? size : SSIZE_T_MAX);
        if (unlikely(ret < 0))
            return -1;

        if (unlikely(ret == 0)) {
            /* nothing was written, only reason for this should
               be out of disk space */
            errno = ENOSPC;
            return -1;
        }

        data = CONST_PTR_OFFSET(data, ret);
        size -= ret;
    }

    return 0;
}

int pwrite_full(int fd, const void *data, size_t size, off_t offset)
{
    ssize_t ret;

    while (size > 0) {
        ret = pwrite(fd, data, size < SSIZE_T_MAX ?
                 size : SSIZE_T_MAX, offset);
        if (unlikely(ret < 0))
            return -1;

        if (unlikely(ret == 0)) {
            /* nothing was written, only reason for this should
               be out of disk space */
            errno = ENOSPC;
            return -1;
        }

        data = CONST_PTR_OFFSET(data, ret);
        size -= ret;
        offset += ret;
    }

    return 0;
}