stdio/common/fputs.c

	fputs.c revision 5d54f3d8999eac1762fe0a8c7177d20f1f201fae
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (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 1995 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*      Copyright (c) 1984 AT&T */
/*        All Rights Reserved   */

#pragma ident   "%Z%%M% %I% %E% SMI"


/*LINTLIBRARY*/
/*
 * This version writes directly to the buffer rather than looping on putc.
 * Ptr args aren't checked for NULL because the program would be a
 * catastrophic mess anyway.  Better to abort than just to return NULL.
 */
#include <stdio.h>
#include "stdiom.h"
#include <errno.h>
#include <memory.h>

static char *memnulccpy(char *, char *, int, int);

int
fputs(char *ptr, FILE *iop)
{
    int ndone = 0, n;
    unsigned char *cptr, *bufend;
    char *p;
    char c;

    if (_WRTCHK(iop)) {
        iop->_flag |= _IOERR;
#ifdef POSIX
        errno = EBADF;
#endif  /* POSIX */
        return (EOF);
    }
    bufend = iop->_base + iop->_bufsiz;

    if ((iop->_flag & _IONBF) == 0)  {
        if (iop->_flag & _IOLBF) {
            for ( ; ; ptr += n) {
                while ((n = bufend - (cptr = iop->_ptr)) <= 0)
                    /* full buf */
                    if (_xflsbuf(iop) == EOF)
                        return(EOF);
                if ((p = memnulccpy((char *) cptr, ptr, '\n', n)) != NULL) {
                    /*
                     * Copy terminated either because we
                     * saw a newline or we saw a NUL (end
                     * of string).
                     */
                    c = *(p - 1);   /* last character moved */
                    if (c == '\0')
                        p--;    /* didn't write '\0' */
                    n = p - (char *) cptr;
                }
                iop->_cnt -= n;
                iop->_ptr += n;
                _BUFSYNC(iop);
                ndone += n;
                if (p != NULL) {
                    /*
                     * We found either a newline or a NUL.
                     * If we found a newline, flush the
                     * buffer.
                     * If we found a NUL, we're done.
                     */
                    if (c == '\n') {
                        if (_xflsbuf(iop) == EOF)
                            return(EOF);
                    } else {
                        /* done */
                        return(ndone);
                    }
                    }
            }
        } else {
            for ( ; ; ptr += n) {
                while ((n = bufend - (cptr = iop->_ptr)) <= 0)
                    /* full buf */
                    if (_xflsbuf(iop) == EOF)
                        return(EOF);
                if ((p = memccpy((char *) cptr, ptr, '\0', n)) != NULL)
                    n = (p - (char *) cptr) - 1;
                iop->_cnt -= n;
                iop->_ptr += n;
                _BUFSYNC(iop);
                ndone += n;
                if (p != NULL)  {
                    /* done */
                        return(ndone);
                    }
            }
        }
    }  else  {
        /* write out to an unbuffered file */
        return (write(iop->_file, ptr, strlen(ptr)));
    }
}

/*
 * Copy s2 to s1, stopping if character c or a NUL is copied.
 * Copy no more than n bytes.
 * Return a pointer to the byte after character c or NUL in the copy,
 * or NULL if c or NUL is not found in the first n bytes.
 */
static char *
memnulccpy(char *s1, char *s2, int c, int n)
{
    int cmoved;

    while (--n >= 0) {
        cmoved = *s2++;
        if ((*s1++ = cmoved) == '\0' || cmoved == c)
            return (s1);
    }
    return (0);
}