isc/unix/stdio.c

	stdio.c revision 0c27b3fe77ac1d5094ba3521e8142d9e7973133f
/*
 * Copyright (C) 2000, 2001, 2004, 2007, 2011-2014, 2016  Internet Systems Consortium, Inc. ("ISC")
 *
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 */

/* $Id$ */

#include <config.h>

#include <errno.h>
#include <unistd.h>

#include <isc/stdio.h>
#include <isc/stat.h>
#include <isc/util.h>

#include "errno2result.h"

isc_result_t
isc_stdio_open(const char *filename, const char *mode, FILE **fp) {
    FILE *f;

    f = fopen(filename, mode);
    if (f == NULL)
        return (isc__errno2result(errno));
    *fp = f;
    return (ISC_R_SUCCESS);
}

isc_result_t
isc_stdio_close(FILE *f) {
    int r;

    r = fclose(f);
    if (r == 0)
        return (ISC_R_SUCCESS);
    else
        return (isc__errno2result(errno));
}

isc_result_t
isc_stdio_seek(FILE *f, off_t offset, int whence) {
    int r;

#ifdef HAVE_FSEEKO
    r = fseeko(f, offset, whence);
#else
    r = fseek(f, offset, whence);
#endif
    if (r == 0)
        return (ISC_R_SUCCESS);
    else
        return (isc__errno2result(errno));
}

isc_result_t
isc_stdio_tell(FILE *f, off_t *offsetp) {
    off_t r;

    REQUIRE(offsetp != NULL);

#ifdef HAVE_FTELLO
    r = ftello(f);
#else
    r = ftell(f);
#endif
    if (r >= 0) {
        *offsetp = r;
        return (ISC_R_SUCCESS);
    } else
        return (isc__errno2result(errno));
}

isc_result_t
isc_stdio_read(void *ptr, size_t size, size_t nmemb, FILE *f, size_t *nret) {
    isc_result_t result = ISC_R_SUCCESS;
    size_t r;

    clearerr(f);
    r = fread(ptr, size, nmemb, f);
    if (r != nmemb) {
        if (feof(f))
            result = ISC_R_EOF;
        else
            result = isc__errno2result(errno);
    }
    if (nret != NULL)
        *nret = r;
    return (result);
}

isc_result_t
isc_stdio_write(const void *ptr, size_t size, size_t nmemb, FILE *f,
           size_t *nret)
{
    isc_result_t result = ISC_R_SUCCESS;
    size_t r;

    clearerr(f);
    r = fwrite(ptr, size, nmemb, f);
    if (r != nmemb)
        result = isc__errno2result(errno);
    if (nret != NULL)
        *nret = r;
    return (result);
}

isc_result_t
isc_stdio_flush(FILE *f) {
    int r;

    r = fflush(f);
    if (r == 0)
        return (ISC_R_SUCCESS);
    else
        return (isc__errno2result(errno));
}

/*
 * OpenBSD has deprecated ENOTSUP in favor of EOPNOTSUPP.
 */
#if defined(EOPNOTSUPP) && !defined(ENOTSUP)
#define ENOTSUP EOPNOTSUPP
#endif

isc_result_t
isc_stdio_sync(FILE *f) {
    int r;

    r = fsync(fileno(f));
    /*
     * fsync is not supported on sockets and pipes which
     * result in EINVAL / ENOTSUP.
     */
    if (r == 0 || errno == EINVAL || errno == ENOTSUP)
        return (ISC_R_SUCCESS);
    else
        return (isc__errno2result(errno));
}