boot/common/boot_utils.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved.
 */

#include <stdio.h>
#include <libintl.h>
#include <errno.h>
#include <assert.h>
#include <unistd.h>
#include "bblk_einfo.h"
#include "boot_utils.h"

boolean_t boot_debug = B_FALSE;
boolean_t nowrite = B_FALSE;

void
boot_gdebug(const char *funcname, char *format, ...)
{
    va_list ap;

    if (boot_debug == B_FALSE)
        return;

    (void) fprintf(stdout, "%s(): ", funcname);

    va_start(ap, format);
    /* LINTED: E_SEC_PRINTF_VAR_FMT */
    (void) vfprintf(stdout, format, ap);
    va_end(ap);
}

/*
 * Common functions to write out and read in block-sized data to a file
 * descriptor.
 */
int
write_out(int fd, void *buffer, size_t size, off_t off)
{
    int     ret;
    char        *buf = buffer;

    if (size % SECTOR_SIZE != 0)
        BOOT_DEBUG("Expected block-sized data, got: %d\n", size);

    /* Dry run. */
    if (nowrite)
        return (BC_SUCCESS);

    for (;;) {
    again:
        ret = pwrite(fd, buf, size, off);
        if (ret == -1) {
            if (errno == EAGAIN)
                goto again;
            else
                return (BC_ERROR);
            }
        if (ret < size) {
            size -= ret;
            off += ret;
            buf += ret;
        } else {
            break;
        }
    }
    return (BC_SUCCESS);
}

int
read_in(int fd, void *buffer, size_t size, off_t off)
{
    int     ret;
    char        *buf = buffer;

    if (size % SECTOR_SIZE != 0)
        BOOT_DEBUG("Expected block-sized data, got: %d\n", size);

    for (;;) {
    again:
        ret = pread(fd, buf, size, off);
        if (ret == -1) {
            if (errno == EAGAIN)
                goto again;
            else
                return (BC_ERROR);
            }
        if (ret < size) {
            size -= ret;
            off += ret;
            buf += ret;
        } else {
            break;
        }
    }
    return (BC_SUCCESS);
}