sys/kern/kern_subr.c

/*
 * Copyright (c) UNIX System Laboratories, Inc.  All or some portions
 * of this file are derived from material licensed to the
 * University of California by American Telephone and Telegraph Co.
 * or UNIX System Laboratories, Inc. and are reproduced herein with
 * the permission of UNIX System Laboratories, Inc.
 */
/*
 * Copyright (c) 1982, 1986, 1991 Regents of the University of California.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *      from: @(#)kern_subr.c   7.7 (Berkeley) 4/15/91
 *      $Id: kern_subr.c,v 1.5 1993/12/19 00:51:31 wollman Exp $
 */

#include "param.h"
#include "systm.h"
#include "proc.h"

int
uiomove(xcp, n, uio)
        register void *xcp;
        register int n;
        register struct uio *uio;
{
        caddr_t cp = (caddr_t)xcp;
        register struct iovec *iov;
        u_int cnt;
        int error = 0;


#ifdef DIAGNOSTIC
        if (uio->uio_rw != UIO_READ && uio->uio_rw != UIO_WRITE)
                panic("uiomove: mode");
        if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc)
                panic("uiomove proc");
#endif
        while (n > 0 && uio->uio_resid) {
                iov = uio->uio_iov;
                cnt = iov->iov_len;
                if (cnt == 0) {
                        uio->uio_iov++;
                        uio->uio_iovcnt--;
                        continue;
                }
                if (cnt > n)
                        cnt = n;
                switch (uio->uio_segflg) {

                case UIO_USERSPACE:
                case UIO_USERISPACE:
                        if (uio->uio_rw == UIO_READ)
                                error = copyout(cp, iov->iov_base, cnt);
                        else
                                error = copyin(iov->iov_base, cp, cnt);
                        if (error)
                                return (error);
                        break;

                case UIO_SYSSPACE:
                        if (uio->uio_rw == UIO_READ)
                                bcopy((caddr_t)cp, iov->iov_base, cnt);
                        else
                                bcopy(iov->iov_base, (caddr_t)cp, cnt);
                        break;
                }
                iov->iov_base += cnt;
                iov->iov_len -= cnt;
                uio->uio_resid -= cnt;
                uio->uio_offset += cnt;
                cp += cnt;
                n -= cnt;
        }
        return (error);
}

int
uioapply(func, arg1, arg2, uio)
        int (*func)() ;
        caddr_t arg1;
        caddr_t arg2;
        register struct uio *uio;
{
        register struct iovec *iov;
        u_int cnt, cnt1;
        int error = 0;


/*#ifdef DIAGNOSTIC*/
        if (uio->uio_rw != UIO_READ && uio->uio_rw != UIO_WRITE)
                panic("uioapply: mode");
        if (uio->uio_segflg == UIO_USERSPACE && uio->uio_procp != curproc)
                panic("uioapply proc");
/*#endif*/
        while (uio->uio_resid) {
                iov = uio->uio_iov;
                cnt = iov->iov_len;
                if (cnt == 0) {
                        uio->uio_iov++;
                        uio->uio_iovcnt--;
                        continue;
                }
                cnt1 = cnt;
                error = (*func)(arg1, arg2, NULL, uio->uio_offset, uio->uio_rw,
                        iov->iov_base, &cnt1, uio->uio_procp);
                cnt -= cnt1;
                iov->iov_base += cnt;
                iov->iov_len -= cnt;
                uio->uio_resid -= cnt;
                uio->uio_offset += cnt;
                if (error || cnt1)
                        return (error);
        }
        return (0);
}

/*
 * Give next character to user as result of read.
 */
int
ureadc(c, uio)
        register int c;
        register struct uio *uio;
{
        register struct iovec *iov;

again:
        if (uio->uio_iovcnt == 0)
                panic("ureadc");
        iov = uio->uio_iov;
        if (iov->iov_len <= 0 || uio->uio_resid <= 0) {
                uio->uio_iovcnt--;
                uio->uio_iov++;
                goto again;
        }
        switch (uio->uio_segflg) {

        case UIO_USERSPACE:
                if (subyte(iov->iov_base, c) < 0)
                        return (EFAULT);
                break;

        case UIO_SYSSPACE:
                *iov->iov_base = c;
                break;

        case UIO_USERISPACE:
                if (suibyte(iov->iov_base, c) < 0)
                        return (EFAULT);
                break;
        }
        iov->iov_base++;
        iov->iov_len--;
        uio->uio_resid--;
        uio->uio_offset++;
        return (0);
}

char *
strcat(src, append)
        register char *src;
        const char *append;
{
        char *old = src;

        for (; *src; ++src)
                ;
        while (*src++ = *append++)
                ;
        return old;
}

char *
strcpy(to, from)
        char *to;
        const char *from;
{
        char *old = to;
        for (; *to = *from; ++from, ++to)
                ;
        return old;
}

char *
strncpy(to, from, cnt)
        char *to;
        const char *from;
        int cnt;
{
        char *old = to;

        for (; cnt && (*to = *from); --cnt, ++from, ++to)
                ;
        *to = '\0';
        return old;
}


int
strcmp(s1, s2)
        register const char *s1, *s2;
{
        while (*s1 == *s2++)
                if (*s1++ == 0)
                        return (0);
        return (*(unsigned char *)s1 - *(unsigned char *)--s2);
}


#ifdef notdef   /* unused except by ct.c, other oddities XXX */
/*
 * Get next character written in by user from uio.
 */
int
uwritec(uio)
        struct uio *uio;
{
        register struct iovec *iov;
        register int c;

        if (uio->uio_resid <= 0)
                return (-1);
again:
        if (uio->uio_iovcnt <= 0)
                panic("uwritec");
        iov = uio->uio_iov;
        if (iov->iov_len == 0) {
                uio->uio_iov++;
                if (--uio->uio_iovcnt == 0)
                        return (-1);
                goto again;
        }
        switch (uio->uio_segflg) {

        case UIO_USERSPACE:
                c = fubyte(iov->iov_base);
                break;

        case UIO_SYSSPACE:
                c = *(u_char *) iov->iov_base;
                break;

        case UIO_USERISPACE:
                c = fuibyte(iov->iov_base);
                break;
        }
        if (c < 0)
                return (-1);
        iov->iov_base++;
        iov->iov_len--;
        uio->uio_resid--;
        uio->uio_offset++;
        return (c);
}
#endif /* notdef */