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diff --git a/src/xdr_rec.c b/src/xdr_rec.c
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+
+/*
+ * Copyright (c) 2009, Sun Microsystems, Inc.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ * - Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * - 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.
+ * - Neither the name of Sun Microsystems, Inc. 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 COPYRIGHT HOLDERS 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 COPYRIGHT HOLDER 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.
+ */
+
+
+/*
+ * xdr_rec.c, Implements TCP/IP based XDR streams with a "record marking"
+ * layer above tcp (for rpc's use).
+ *
+ * Copyright (C) 1984, Sun Microsystems, Inc.
+ *
+ * These routines interface XDRSTREAMS to a tcp/ip connection.
+ * There is a record marking layer between the xdr stream
+ * and the tcp transport level. A record is composed on one or more
+ * record fragments. A record fragment is a thirty-two bit header followed
+ * by n bytes of data, where n is contained in the header. The header
+ * is represented as a htonl(u_long). Thegh order bit encodes
+ * whether or not the fragment is the last fragment of the record
+ * (1 => fragment is last, 0 => more fragments to follow.
+ * The other 31 bits encode the byte length of the fragment.
+ */
+
+#include <sys/types.h>
+
+#include <netinet/in.h>
+
+#include <err.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <rpc/types.h>
+#include <rpc/xdr.h>
+#include <rpc/auth.h>
+#include <rpc/svc_auth.h>
+#include <rpc/svc.h>
+#include <rpc/clnt.h>
+#include <stddef.h>
+#include <errno.h>
+#include "rpc_com.h"
+static bool_t xdrrec_getlong(XDR *, long *);
+static bool_t xdrrec_putlong(XDR *, const long *);
+static bool_t xdrrec_getbytes(XDR *, char *, u_int);
+
+static bool_t xdrrec_putbytes(XDR *, const char *, u_int);
+static u_int xdrrec_getpos(XDR *);
+static bool_t xdrrec_setpos(XDR *, u_int);
+static int32_t *xdrrec_inline(XDR *, u_int);
+static void xdrrec_destroy(XDR *);
+
+static const struct xdr_ops xdrrec_ops = {
+ xdrrec_getlong,
+ xdrrec_putlong,
+ xdrrec_getbytes,
+ xdrrec_putbytes,
+ xdrrec_getpos,
+ xdrrec_setpos,
+ xdrrec_inline,
+ xdrrec_destroy
+};
+
+/*
+ * A record is composed of one or more record fragments.
+ * A record fragment is a four-byte header followed by zero to
+ * 2**32-1 bytes. The header is treated as a long unsigned and is
+ * encode/decoded to the network via htonl/ntohl. The low order 31 bits
+ * are a byte count of the fragment. The highest order bit is a boolean:
+ * 1 => this fragment is the last fragment of the record,
+ * 0 => this fragment is followed by more fragment(s).
+ *
+ * The fragment/record machinery is not general; it is constructed to
+ * meet the needs of xdr and rpc based on tcp.
+ */
+
+#define LAST_FRAG ((u_int32_t)(1 << 31))
+
+typedef struct rec_strm {
+ char *tcp_handle;
+ /*
+ * out-goung bits
+ */
+ int (*writeit)(void *, void *, int);
+ char *out_base; /* output buffer (points to frag header) */
+ char *out_finger; /* next output position */
+ char *out_boundry; /* data cannot up to this address */
+ u_int32_t *frag_header; /* beginning of curren fragment */
+ bool_t frag_sent; /* true if buffer sent in middle of record */
+ /*
+ * in-coming bits
+ */
+ int (*readit)(void *, void *, int);
+ u_long in_size; /* fixed size of the input buffer */
+ char *in_base;
+ char *in_finger; /* location of next byte to be had */
+ char *in_boundry; /* can read up to this location */
+ long fbtbc; /* fragment bytes to be consumed */
+ bool_t last_frag;
+ u_int sendsize;
+ u_int recvsize;
+
+ bool_t nonblock;
+ bool_t in_haveheader;
+ u_int32_t in_header;
+ char *in_hdrp;
+ int in_hdrlen;
+ int in_reclen;
+ int in_received;
+ int in_maxrec;
+} RECSTREAM;
+
+static u_int fix_buf_size(u_int);
+static bool_t flush_out(RECSTREAM *, bool_t);
+static bool_t fill_input_buf(RECSTREAM *);
+static bool_t get_input_bytes(RECSTREAM *, char *, int);
+static bool_t set_input_fragment(RECSTREAM *);
+static bool_t skip_input_bytes(RECSTREAM *, long);
+static bool_t realloc_stream(RECSTREAM *, int);
+
+
+/*
+ * Create an xdr handle for xdrrec
+ * xdrrec_create fills in xdrs. Sendsize and recvsize are
+ * send and recv buffer sizes (0 => use default).
+ * tcp_handle is an opaque handle that is passed as the first parameter to
+ * the procedures readit and writeit. Readit and writeit are read and
+ * write respectively. They are like the system
+ * calls expect that they take an opaque handle rather than an fd.
+ */
+void
+xdrrec_create(xdrs, sendsize, recvsize, tcp_handle, readit, writeit)
+ XDR *xdrs;
+ u_int sendsize;
+ u_int recvsize;
+ void *tcp_handle;
+ /* like read, but pass it a tcp_handle, not sock */
+ int (*readit)(void *, void *, int);
+ /* like write, but pass it a tcp_handle, not sock */
+ int (*writeit)(void *, void *, int);
+{
+ RECSTREAM *rstrm = mem_alloc(sizeof(RECSTREAM));
+
+ if (rstrm == NULL) {
+ warnx("xdrrec_create: out of memory");
+ /*
+ * This is bad. Should rework xdrrec_create to
+ * return a handle, and in this case return NULL
+ */
+ return;
+ }
+ rstrm->sendsize = sendsize = fix_buf_size(sendsize);
+ rstrm->out_base = mem_alloc(rstrm->sendsize);
+ if (rstrm->out_base == NULL) {
+ warnx("xdrrec_create: out of memory");
+ mem_free(rstrm, sizeof(RECSTREAM));
+ return;
+ }
+ rstrm->recvsize = recvsize = fix_buf_size(recvsize);
+ rstrm->in_base = mem_alloc(recvsize);
+ if (rstrm->in_base == NULL) {
+ warnx("xdrrec_create: out of memory");
+ mem_free(rstrm->out_base, sendsize);
+ mem_free(rstrm, sizeof(RECSTREAM));
+ return;
+ }
+ /*
+ * now the rest ...
+ */
+ xdrs->x_ops = &xdrrec_ops;
+ xdrs->x_private = rstrm;
+ rstrm->tcp_handle = tcp_handle;
+ rstrm->readit = readit;
+ rstrm->writeit = writeit;
+ rstrm->out_finger = rstrm->out_boundry = rstrm->out_base;
+ rstrm->frag_header = (u_int32_t *)(void *)rstrm->out_base;
+ rstrm->out_finger += sizeof(u_int32_t);
+ rstrm->out_boundry += sendsize;
+ rstrm->frag_sent = FALSE;
+ rstrm->in_size = recvsize;
+ rstrm->in_boundry = rstrm->in_base;
+ rstrm->in_finger = (rstrm->in_boundry += recvsize);
+ rstrm->fbtbc = 0;
+ rstrm->last_frag = TRUE;
+ rstrm->in_haveheader = FALSE;
+ rstrm->in_hdrlen = 0;
+ rstrm->in_hdrp = (char *)(void *)&rstrm->in_header;
+ rstrm->nonblock = FALSE;
+ rstrm->in_reclen = 0;
+ rstrm->in_received = 0;
+}
+
+
+/*
+ * The reoutines defined below are the xdr ops which will go into the
+ * xdr handle filled in by xdrrec_create.
+ */
+
+static bool_t
+xdrrec_getlong(xdrs, lp)
+ XDR *xdrs;
+ long *lp;
+{
+ RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private);
+ int32_t *buflp = (int32_t *)(void *)(rstrm->in_finger);
+ int32_t mylong;
+
+ /* first try the inline, fast case */
+ if ((rstrm->fbtbc >= sizeof(int32_t)) &&
+ (((long)rstrm->in_boundry - (long)buflp) >= sizeof(int32_t))) {
+ *lp = (long)ntohl((u_int32_t)(*buflp));
+ rstrm->fbtbc -= sizeof(int32_t);
+ rstrm->in_finger += sizeof(int32_t);
+ } else {
+ if (! xdrrec_getbytes(xdrs, (char *)(void *)&mylong,
+ sizeof(int32_t)))
+ return (FALSE);
+ *lp = (long)ntohl((u_int32_t)mylong);
+ }
+ return (TRUE);
+}
+
+static bool_t
+xdrrec_putlong(xdrs, lp)
+ XDR *xdrs;
+ const long *lp;
+{
+ RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private);
+ int32_t *dest_lp = ((int32_t *)(void *)(rstrm->out_finger));
+
+ if ((rstrm->out_finger += sizeof(int32_t)) > rstrm->out_boundry) {
+ /*
+ * this case should almost never happen so the code is
+ * inefficient
+ */
+ rstrm->out_finger -= sizeof(int32_t);
+ rstrm->frag_sent = TRUE;
+ if (! flush_out(rstrm, FALSE))
+ return (FALSE);
+ dest_lp = ((int32_t *)(void *)(rstrm->out_finger));
+ rstrm->out_finger += sizeof(int32_t);
+ }
+ *dest_lp = (int32_t)htonl((u_int32_t)(*lp));
+ return (TRUE);
+}
+
+static bool_t /* must manage buffers, fragments, and records */
+xdrrec_getbytes(xdrs, addr, len)
+ XDR *xdrs;
+ char *addr;
+ u_int len;
+{
+ RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private);
+ int current;
+
+ while (len > 0) {
+ current = (int)rstrm->fbtbc;
+ if (current == 0) {
+ if (rstrm->last_frag)
+ return (FALSE);
+ if (! set_input_fragment(rstrm))
+ return (FALSE);
+ continue;
+ }
+ current = (len < current) ? len : current;
+ if (! get_input_bytes(rstrm, addr, current))
+ return (FALSE);
+ addr += current;
+ rstrm->fbtbc -= current;
+ len -= current;
+ }
+ return (TRUE);
+}
+
+static bool_t
+xdrrec_putbytes(xdrs, addr, len)
+ XDR *xdrs;
+ const char *addr;
+ u_int len;
+{
+ RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private);
+ size_t current;
+
+ while (len > 0) {
+ current = (size_t)((u_long)rstrm->out_boundry -
+ (u_long)rstrm->out_finger);
+ current = (len < current) ? len : current;
+ memmove(rstrm->out_finger, addr, current);
+ rstrm->out_finger += current;
+ addr += current;
+ len -= current;
+ if (rstrm->out_finger == rstrm->out_boundry) {
+ rstrm->frag_sent = TRUE;
+ if (! flush_out(rstrm, FALSE))
+ return (FALSE);
+ }
+ }
+ return (TRUE);
+}
+
+static u_int
+xdrrec_getpos(xdrs)
+ XDR *xdrs;
+{
+ RECSTREAM *rstrm = (RECSTREAM *)xdrs->x_private;
+ off_t pos;
+
+ switch (xdrs->x_op) {
+
+ case XDR_ENCODE:
+ pos = rstrm->out_finger - rstrm->out_base
+ - BYTES_PER_XDR_UNIT;
+ break;
+
+ case XDR_DECODE:
+ pos = rstrm->in_boundry - rstrm->in_finger
+ - BYTES_PER_XDR_UNIT;
+ break;
+
+ default:
+ pos = (off_t) -1;
+ break;
+ }
+ return ((u_int) pos);
+}
+
+static bool_t
+xdrrec_setpos(xdrs, pos)
+ XDR *xdrs;
+ u_int pos;
+{
+ RECSTREAM *rstrm = (RECSTREAM *)xdrs->x_private;
+ u_int currpos = xdrrec_getpos(xdrs);
+ int delta = currpos - pos;
+ char *newpos;
+
+ if ((int)currpos != -1)
+ switch (xdrs->x_op) {
+
+ case XDR_ENCODE:
+ newpos = rstrm->out_finger - delta;
+ if ((newpos > (char *)(void *)(rstrm->frag_header)) &&
+ (newpos < rstrm->out_boundry)) {
+ rstrm->out_finger = newpos;
+ return (TRUE);
+ }
+ break;
+
+ case XDR_DECODE:
+ newpos = rstrm->in_finger - delta;
+ if ((delta < (int)(rstrm->fbtbc)) &&
+ (newpos <= rstrm->in_boundry) &&
+ (newpos >= rstrm->in_base)) {
+ rstrm->in_finger = newpos;
+ rstrm->fbtbc -= delta;
+ return (TRUE);
+ }
+ break;
+
+ case XDR_FREE:
+ break;
+ }
+ return (FALSE);
+}
+
+static int32_t *
+xdrrec_inline(xdrs, len)
+ XDR *xdrs;
+ u_int len;
+{
+ RECSTREAM *rstrm = (RECSTREAM *)xdrs->x_private;
+ int32_t *buf = NULL;
+
+ switch (xdrs->x_op) {
+
+ case XDR_ENCODE:
+ if ((rstrm->out_finger + len) <= rstrm->out_boundry) {
+ buf = (int32_t *)(void *)rstrm->out_finger;
+ rstrm->out_finger += len;
+ }
+ break;
+
+ case XDR_DECODE:
+ if ((len <= rstrm->fbtbc) &&
+ ((rstrm->in_finger + len) <= rstrm->in_boundry)) {
+ buf = (int32_t *)(void *)rstrm->in_finger;
+ rstrm->fbtbc -= len;
+ rstrm->in_finger += len;
+ }
+ break;
+
+ case XDR_FREE:
+ break;
+ }
+ return (buf);
+}
+
+static void
+xdrrec_destroy(xdrs)
+ XDR *xdrs;
+{
+ RECSTREAM *rstrm = (RECSTREAM *)xdrs->x_private;
+
+ mem_free(rstrm->out_base, rstrm->sendsize);
+ mem_free(rstrm->in_base, rstrm->recvsize);
+ mem_free(rstrm, sizeof(RECSTREAM));
+}
+
+
+/*
+ * Exported routines to manage xdr records
+ */
+
+/*
+ * Before reading (deserializing from the stream, one should always call
+ * this procedure to guarantee proper record alignment.
+ */
+bool_t
+xdrrec_skiprecord(xdrs)
+ XDR *xdrs;
+{
+ RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private);
+ enum xprt_stat xstat;
+
+ if (rstrm->nonblock) {
+ if (__xdrrec_getrec(xdrs, &xstat, FALSE)) {
+ rstrm->fbtbc = 0;
+ return TRUE;
+ }
+ if (rstrm->in_finger == rstrm->in_boundry &&
+ xstat == XPRT_MOREREQS) {
+ rstrm->fbtbc = 0;
+ return TRUE;
+ }
+ return FALSE;
+ }
+
+ while (rstrm->fbtbc > 0 || (! rstrm->last_frag)) {
+ if (! skip_input_bytes(rstrm, rstrm->fbtbc))
+ return (FALSE);
+ rstrm->fbtbc = 0;
+ if ((! rstrm->last_frag) && (! set_input_fragment(rstrm)))
+ return (FALSE);
+ }
+ rstrm->last_frag = FALSE;
+ return (TRUE);
+}
+
+/*
+ * Look ahead function.
+ * Returns TRUE iff there is no more input in the buffer
+ * after consuming the rest of the current record.
+ */
+bool_t
+xdrrec_eof(xdrs)
+ XDR *xdrs;
+{
+ RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private);
+
+ while (rstrm->fbtbc > 0 || (! rstrm->last_frag)) {
+ if (! skip_input_bytes(rstrm, rstrm->fbtbc))
+ return (TRUE);
+ rstrm->fbtbc = 0;
+ if ((! rstrm->last_frag) && (! set_input_fragment(rstrm)))
+ return (TRUE);
+ }
+ if (rstrm->in_finger == rstrm->in_boundry)
+ return (TRUE);
+ return (FALSE);
+}
+
+/*
+ * The client must tell the package when an end-of-record has occurred.
+ * The second paraemters tells whether the record should be flushed to the
+ * (output) tcp stream. (This let's the package support batched or
+ * pipelined procedure calls.) TRUE => immmediate flush to tcp connection.
+ */
+bool_t
+xdrrec_endofrecord(xdrs, sendnow)
+ XDR *xdrs;
+ bool_t sendnow;
+{
+ RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private);
+ u_long len; /* fragment length */
+
+ if (sendnow || rstrm->frag_sent ||
+ ((u_long)rstrm->out_finger + sizeof(u_int32_t) >=
+ (u_long)rstrm->out_boundry)) {
+ rstrm->frag_sent = FALSE;
+ return (flush_out(rstrm, TRUE));
+ }
+ len = (u_long)(rstrm->out_finger) - (u_long)(rstrm->frag_header) -
+ sizeof(u_int32_t);
+ *(rstrm->frag_header) = htonl((u_int32_t)len | LAST_FRAG);
+ rstrm->frag_header = (u_int32_t *)(void *)rstrm->out_finger;
+ rstrm->out_finger += sizeof(u_int32_t);
+ return (TRUE);
+}
+
+/*
+ * Fill the stream buffer with a record for a non-blocking connection.
+ * Return true if a record is available in the buffer, false if not.
+ */
+bool_t
+__xdrrec_getrec(xdrs, statp, expectdata)
+ XDR *xdrs;
+ enum xprt_stat *statp;
+ bool_t expectdata;
+{
+ RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private);
+ ssize_t n;
+ int fraglen;
+
+ if (!rstrm->in_haveheader) {
+ n = rstrm->readit(rstrm->tcp_handle, rstrm->in_hdrp,
+ (int)sizeof (rstrm->in_header) - rstrm->in_hdrlen);
+ if (n == 0) {
+ /* EAGAIN or EWOULDBLOCK means a zero length
+ * read not an EOF.
+ */
+ if (errno == EAGAIN || errno == EWOULDBLOCK)
+ *statp = XPRT_IDLE;
+ else
+ *statp = expectdata ? XPRT_DIED : XPRT_IDLE;
+ return FALSE;
+ }
+ if (n < 0) {
+ *statp = XPRT_DIED;
+ return FALSE;
+ }
+ rstrm->in_hdrp += n;
+ rstrm->in_hdrlen += n;
+ if (rstrm->in_hdrlen < sizeof (rstrm->in_header)) {
+ *statp = XPRT_MOREREQS;
+ return FALSE;
+ }
+ rstrm->in_header = ntohl(rstrm->in_header);
+ fraglen = (int)(rstrm->in_header & ~LAST_FRAG);
+ if (fraglen == 0 || fraglen > rstrm->in_maxrec ||
+ (rstrm->in_reclen + fraglen) > rstrm->in_maxrec) {
+ *statp = XPRT_DIED;
+ return FALSE;
+ }
+ rstrm->in_reclen += fraglen;
+ if (rstrm->in_reclen > rstrm->recvsize)
+ realloc_stream(rstrm, rstrm->in_reclen);
+ if (rstrm->in_header & LAST_FRAG) {
+ rstrm->in_header &= ~LAST_FRAG;
+ rstrm->last_frag = TRUE;
+ }
+ rstrm->in_haveheader = 1;
+ }
+
+ n = rstrm->readit(rstrm->tcp_handle,
+ rstrm->in_base + rstrm->in_received,
+ (rstrm->in_reclen - rstrm->in_received));
+
+ if (n < 0) {
+ *statp = XPRT_DIED;
+ return FALSE;
+ }
+
+ if (n == 0) {
+ /* EAGAIN or EWOULDBLOCK means a zero length
+ * read not an EOF.
+ */
+ if (errno == EAGAIN || errno == EWOULDBLOCK)
+ *statp = XPRT_IDLE;
+ else
+ *statp = expectdata ? XPRT_DIED : XPRT_IDLE;
+ return FALSE;
+ }
+
+ rstrm->in_received += n;
+
+ if (rstrm->in_received == rstrm->in_reclen) {
+ rstrm->in_haveheader = FALSE;
+ rstrm->in_hdrp = (char *)(void *)&rstrm->in_header;
+ rstrm->in_hdrlen = 0;
+ if (rstrm->last_frag) {
+ rstrm->fbtbc = rstrm->in_reclen;
+ rstrm->in_boundry = rstrm->in_base + rstrm->in_reclen;
+ rstrm->in_finger = rstrm->in_base;
+ rstrm->in_reclen = rstrm->in_received = 0;
+ *statp = XPRT_MOREREQS;
+ return TRUE;
+ }
+ }
+
+ *statp = XPRT_MOREREQS;
+ return FALSE;
+}
+
+bool_t
+__xdrrec_setnonblock(xdrs, maxrec)
+ XDR *xdrs;
+ int maxrec;
+{
+ RECSTREAM *rstrm = (RECSTREAM *)(xdrs->x_private);
+
+ rstrm->nonblock = TRUE;
+ if (maxrec == 0)
+ maxrec = rstrm->recvsize;
+ rstrm->in_maxrec = maxrec;
+ return TRUE;
+}
+
+/*
+ * Internal useful routines
+ */
+static bool_t
+flush_out(rstrm, eor)
+ RECSTREAM *rstrm;
+ bool_t eor;
+{
+ u_int32_t eormask = (eor == TRUE) ? LAST_FRAG : 0;
+ u_int32_t len = (u_int32_t)((u_long)(rstrm->out_finger) -
+ (u_long)(rstrm->frag_header) - sizeof(u_int32_t));
+
+ *(rstrm->frag_header) = htonl(len | eormask);
+ len = (u_int32_t)((u_long)(rstrm->out_finger) -
+ (u_long)(rstrm->out_base));
+ if ((*(rstrm->writeit))(rstrm->tcp_handle, rstrm->out_base, (int)len)
+ != (int)len)
+ return (FALSE);
+ rstrm->frag_header = (u_int32_t *)(void *)rstrm->out_base;
+ rstrm->out_finger = (char *)rstrm->out_base + sizeof(u_int32_t);
+ return (TRUE);
+}
+
+static bool_t /* knows nothing about records! Only about input buffers */
+fill_input_buf(rstrm)
+ RECSTREAM *rstrm;
+{
+ char *where;
+ u_int32_t i;
+ int len;
+
+ if (rstrm->nonblock)
+ return FALSE;
+
+ where = rstrm->in_base;
+ i = (u_int32_t)((u_long)rstrm->in_boundry % BYTES_PER_XDR_UNIT);
+ where += i;
+ len = (u_int32_t)(rstrm->in_size - i);
+ if ((len = (*(rstrm->readit))(rstrm->tcp_handle, where, len)) == -1)
+ return (FALSE);
+ rstrm->in_finger = where;
+ where += len;
+ rstrm->in_boundry = where;
+ return (TRUE);
+}
+
+static bool_t /* knows nothing about records! Only about input buffers */
+get_input_bytes(rstrm, addr, len)
+ RECSTREAM *rstrm;
+ char *addr;
+ int len;
+{
+ size_t current;
+
+ if (rstrm->nonblock) {
+ if (len > (int)(rstrm->in_boundry - rstrm->in_finger))
+ return FALSE;
+ memcpy(addr, rstrm->in_finger, (size_t)len);
+ rstrm->in_finger += len;
+ return TRUE;
+ }
+
+ while (len > 0) {
+ current = (size_t)((long)rstrm->in_boundry -
+ (long)rstrm->in_finger);
+ if (current == 0) {
+ if (! fill_input_buf(rstrm))
+ return (FALSE);
+ continue;
+ }
+ current = (len < current) ? len : current;
+ memmove(addr, rstrm->in_finger, current);
+ rstrm->in_finger += current;
+ addr += current;
+ len -= current;
+ }
+ return (TRUE);
+}
+
+static bool_t /* next two bytes of the input stream are treated as a header */
+set_input_fragment(rstrm)
+ RECSTREAM *rstrm;
+{
+ u_int32_t header;
+
+ if (rstrm->nonblock)
+ return FALSE;
+ if (! get_input_bytes(rstrm, (char *)(void *)&header, sizeof(header)))
+ return (FALSE);
+ header = ntohl(header);
+ rstrm->last_frag = ((header & LAST_FRAG) == 0) ? FALSE : TRUE;
+ /*
+ * Sanity check. Try not to accept wildly incorrect
+ * record sizes. Unfortunately, the only record size
+ * we can positively identify as being 'wildly incorrect'
+ * is zero. Ridiculously large record sizes may look wrong,
+ * but we don't have any way to be certain that they aren't
+ * what the client actually intended to send us.
+ */
+ if (header == 0)
+ return(FALSE);
+ rstrm->fbtbc = header & (~LAST_FRAG);
+ return (TRUE);
+}
+
+static bool_t /* consumes input bytes; knows nothing about records! */
+skip_input_bytes(rstrm, cnt)
+ RECSTREAM *rstrm;
+ long cnt;
+{
+ u_int32_t current;
+
+ while (cnt > 0) {
+ current = (size_t)((long)rstrm->in_boundry -
+ (long)rstrm->in_finger);
+ if (current == 0) {
+ if (! fill_input_buf(rstrm))
+ return (FALSE);
+ continue;
+ }
+ current = (u_int32_t)((cnt < current) ? cnt : current);
+ rstrm->in_finger += current;
+ cnt -= current;
+ }
+ return (TRUE);
+}
+
+static u_int
+fix_buf_size(s)
+ u_int s;
+{
+
+ if (s < 100)
+ s = 4000;
+ return (RNDUP(s));
+}
+
+/*
+ * Reallocate the input buffer for a non-block stream.
+ */
+static bool_t
+realloc_stream(rstrm, size)
+ RECSTREAM *rstrm;
+ int size;
+{
+ ptrdiff_t diff;
+ char *buf;
+
+ if (size > rstrm->recvsize) {
+ buf = realloc(rstrm->in_base, (size_t)size);
+ if (buf == NULL)
+ return FALSE;
+ diff = buf - rstrm->in_base;
+ rstrm->in_finger += diff;
+ rstrm->in_base = buf;
+ rstrm->in_boundry = buf + size;
+ rstrm->recvsize = size;
+ rstrm->in_size = size;
+ }
+
+ return TRUE;
+}