diff options
Diffstat (limited to 'sys/xdr/xdr_mbuf.c')
-rw-r--r-- | sys/xdr/xdr_mbuf.c | 238 |
1 files changed, 238 insertions, 0 deletions
diff --git a/sys/xdr/xdr_mbuf.c b/sys/xdr/xdr_mbuf.c new file mode 100644 index 0000000..770dfc3 --- /dev/null +++ b/sys/xdr/xdr_mbuf.c @@ -0,0 +1,238 @@ +/*- + * Copyright (c) 2008 Isilon Inc http://www.isilon.com/ + * Authors: Doug Rabson <dfr@rabson.org> + * Developed with Red Inc: Alfred Perlstein <alfred@freebsd.org> + * + * 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. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/param.h> +#include <sys/systm.h> +#include <sys/malloc.h> +#include <sys/mbuf.h> + +#include <rpc/types.h> +#include <rpc/xdr.h> + +static void xdrmbuf_destroy(XDR *); +static bool_t xdrmbuf_getlong(XDR *, long *); +static bool_t xdrmbuf_putlong(XDR *, const long *); +static bool_t xdrmbuf_getbytes(XDR *, char *, u_int); +static bool_t xdrmbuf_putbytes(XDR *, const char *, u_int); +/* XXX: w/64-bit pointers, u_int not enough! */ +static u_int xdrmbuf_getpos(XDR *); +static bool_t xdrmbuf_setpos(XDR *, u_int); +static int32_t *xdrmbuf_inline(XDR *, u_int); + +static const struct xdr_ops xdrmbuf_ops = { + xdrmbuf_getlong, + xdrmbuf_putlong, + xdrmbuf_getbytes, + xdrmbuf_putbytes, + xdrmbuf_getpos, + xdrmbuf_setpos, + xdrmbuf_inline, + xdrmbuf_destroy +}; + +/* + * The procedure xdrmbuf_create initializes a stream descriptor for a + * mbuf. + */ +void +xdrmbuf_create(XDR *xdrs, struct mbuf *m, enum xdr_op op) +{ + + xdrs->x_op = op; + xdrs->x_ops = &xdrmbuf_ops; + xdrs->x_base = (char *) m; + if (op == XDR_ENCODE) { + m = m_last(m); + xdrs->x_private = m; + xdrs->x_handy = m->m_len; + } else { + xdrs->x_private = m; + xdrs->x_handy = 0; + } +} + +static void +xdrmbuf_destroy(XDR *xdrs) +{ + + if (xdrs->x_op == XDR_DECODE && xdrs->x_base) { + m_freem((struct mbuf *) xdrs->x_base); + xdrs->x_base = NULL; + xdrs->x_private = NULL; + } +} + +static bool_t +xdrmbuf_getlong(XDR *xdrs, long *lp) +{ + int32_t t; + + xdrmbuf_getbytes(xdrs, (char *) &t, sizeof(int32_t)); + *lp = ntohl(t); + return (TRUE); +} + +static bool_t +xdrmbuf_putlong(xdrs, lp) + XDR *xdrs; + const long *lp; +{ + int32_t t = htonl(*lp); + + xdrmbuf_putbytes(xdrs, (char *) &t, sizeof(int32_t)); + return (TRUE); +} + +static bool_t +xdrmbuf_getbytes(XDR *xdrs, char *addr, u_int len) +{ + struct mbuf *m = (struct mbuf *) xdrs->x_private; + size_t sz; + + while (len > 0) { + /* + * Make sure we haven't hit the end. + */ + if (!m) { + return (FALSE); + } + + /* + * See how much we can get from this mbuf. + */ + sz = m->m_len - xdrs->x_handy; + if (sz > len) + sz = len; + memcpy(addr, mtod(m, const char *) + xdrs->x_handy, sz); + + addr += sz; + xdrs->x_handy += sz; + len -= sz; + + if (xdrs->x_handy == m->m_len) { + m = m->m_next; + xdrs->x_private = (void *) m; + xdrs->x_handy = 0; + } + } + + return (TRUE); +} + +static bool_t +xdrmbuf_putbytes(XDR *xdrs, const char *addr, u_int len) +{ + struct mbuf *m = (struct mbuf *) xdrs->x_private; + struct mbuf *n; + size_t sz; + + while (len > 0) { + sz = M_TRAILINGSPACE(m) + (m->m_len - xdrs->x_handy); + if (sz > len) + sz = len; + memcpy(mtod(m, char *) + xdrs->x_handy, addr, sz); + addr += sz; + xdrs->x_handy += sz; + if (xdrs->x_handy > m->m_len) + m->m_len = xdrs->x_handy; + len -= sz; + + if (xdrs->x_handy == m->m_len && M_TRAILINGSPACE(m) == 0) { + if (!m->m_next) { + MGET(n, M_TRYWAIT, m->m_type); + m->m_next = n; + } + m = m->m_next; + xdrs->x_private = (void *) m; + xdrs->x_handy = 0; + } + } + + return (TRUE); +} + +static u_int +xdrmbuf_getpos(XDR *xdrs) +{ + struct mbuf *m0 = (struct mbuf *) xdrs->x_base; + struct mbuf *m = (struct mbuf *) xdrs->x_private; + u_int pos = 0; + + while (m0 && m0 != m) { + pos += m0->m_len; + m0 = m0->m_next; + } + KASSERT(m0, ("Corrupted mbuf chain")); + + return (pos + xdrs->x_handy); +} + +static bool_t +xdrmbuf_setpos(XDR *xdrs, u_int pos) +{ + struct mbuf *m = (struct mbuf *) xdrs->x_base; + + while (m && pos > m->m_len) { + pos -= m->m_len; + m = m->m_next; + } + KASSERT(m, ("Corrupted mbuf chain")); + + xdrs->x_private = (void *) m; + xdrs->x_handy = pos; + + return (TRUE); +} + +static int32_t * +xdrmbuf_inline(XDR *xdrs, u_int len) +{ + struct mbuf *m = (struct mbuf *) xdrs->x_private; + size_t available; + char *p; + + if (xdrs->x_op == XDR_ENCODE) { + available = M_TRAILINGSPACE(m) + (m->m_len - xdrs->x_handy); + } else { + available = m->m_len - xdrs->x_handy; + } + + if (available >= len) { + p = mtod(m, char *) + xdrs->x_handy; + if (((uintptr_t) p) & (sizeof(int32_t) - 1)) + return (0); + xdrs->x_handy += len; + if (xdrs->x_handy > m->m_len) + m->m_len = xdrs->x_handy; + return ((int32_t *) p); + } + + return (0); +} |