1 /* $OpenBSD: xdr_stdio.c,v 1.17 2022/05/14 05:06:32 guenther Exp $ */
2
3 /*
4 * Copyright (c) 2010, Oracle America, Inc.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are
8 * met:
9 *
10 * * Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * * Redistributions in binary form must reproduce the above
13 * copyright notice, this list of conditions and the following
14 * disclaimer in the documentation and/or other materials
15 * provided with the distribution.
16 * * Neither the name of the "Oracle America, Inc." nor the names of its
17 * contributors may be used to endorse or promote products derived
18 * from this software without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
23 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
24 * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
25 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
27 * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
28 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
30 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 */
33
34 /*
35 * xdr_stdio.c, XDR implementation on standard i/o file.
36 *
37 * This set of routines implements a XDR on a stdio stream.
38 * XDR_ENCODE serializes onto the stream, XDR_DECODE de-serializes
39 * from the stream.
40 */
41
42 #include <stdio.h>
43 #include <rpc/types.h>
44 #include <rpc/xdr.h>
45
46 static bool_t xdrstdio_getlong(XDR *, long *);
47 static bool_t xdrstdio_putlong(XDR *, long *);
48 static bool_t xdrstdio_getbytes(XDR *, caddr_t, u_int);
49 static bool_t xdrstdio_putbytes(XDR *, caddr_t, u_int);
50 static u_int xdrstdio_getpos(XDR *);
51 static bool_t xdrstdio_setpos(XDR *, u_int);
52 static int32_t *xdrstdio_inline(XDR *, u_int);
53 static void xdrstdio_destroy(XDR *);
54
55 /*
56 * Ops vector for stdio type XDR
57 */
58 static const struct xdr_ops xdrstdio_ops = {
59 xdrstdio_getlong, /* deserialize a long int */
60 xdrstdio_putlong, /* serialize a long int */
61 xdrstdio_getbytes, /* deserialize counted bytes */
62 xdrstdio_putbytes, /* serialize counted bytes */
63 xdrstdio_getpos, /* get offset in the stream */
64 xdrstdio_setpos, /* set offset in the stream */
65 xdrstdio_inline, /* prime stream for inline macros */
66 xdrstdio_destroy, /* destroy stream */
67 NULL, /* xdrstdio_control */
68 };
69
70 /*
71 * Initialize a stdio xdr stream.
72 * Sets the xdr stream handle xdrs for use on the stream file.
73 * Operation flag is set to op.
74 */
75 void
xdrstdio_create(XDR * xdrs,FILE * file,enum xdr_op op)76 xdrstdio_create(XDR *xdrs, FILE *file, enum xdr_op op)
77 {
78
79 xdrs->x_op = op;
80 xdrs->x_ops = &xdrstdio_ops;
81 xdrs->x_private = (caddr_t)file;
82 xdrs->x_handy = 0;
83 xdrs->x_base = 0;
84 }
85
86 /*
87 * Destroy a stdio xdr stream.
88 * Cleans up the xdr stream handle xdrs previously set up by xdrstdio_create.
89 */
90 static void
xdrstdio_destroy(XDR * xdrs)91 xdrstdio_destroy(XDR *xdrs)
92 {
93 (void)fflush((FILE *)xdrs->x_private);
94 /* xx should we close the file ?? */
95 }
96
97 static bool_t
xdrstdio_getlong(XDR * xdrs,long int * lp)98 xdrstdio_getlong(XDR *xdrs, long int *lp)
99 {
100 u_int32_t temp;
101
102 if (fread(&temp, sizeof(int32_t), 1, (FILE *)xdrs->x_private) != 1)
103 return (FALSE);
104 *lp = (long)ntohl(temp);
105 return (TRUE);
106 }
107
108 static bool_t
xdrstdio_putlong(XDR * xdrs,long int * lp)109 xdrstdio_putlong(XDR *xdrs, long int *lp)
110 {
111 int32_t mycopy = htonl((u_int32_t)*lp);
112
113 if (fwrite(&mycopy, sizeof(int32_t), 1, (FILE *)xdrs->x_private) != 1)
114 return (FALSE);
115 return (TRUE);
116 }
117
118 static bool_t
xdrstdio_getbytes(XDR * xdrs,caddr_t addr,u_int len)119 xdrstdio_getbytes(XDR *xdrs, caddr_t addr, u_int len)
120 {
121
122 if ((len != 0) && (fread(addr, (int)len, 1, (FILE *)xdrs->x_private) != 1))
123 return (FALSE);
124 return (TRUE);
125 }
126
127 static bool_t
xdrstdio_putbytes(XDR * xdrs,caddr_t addr,u_int len)128 xdrstdio_putbytes(XDR *xdrs, caddr_t addr, u_int len)
129 {
130
131 if ((len != 0) && (fwrite(addr, (int)len, 1, (FILE *)xdrs->x_private) != 1))
132 return (FALSE);
133 return (TRUE);
134 }
135
136 static u_int
xdrstdio_getpos(XDR * xdrs)137 xdrstdio_getpos(XDR *xdrs)
138 {
139
140 return ((u_int) ftell((FILE *)xdrs->x_private));
141 }
142
143 static bool_t
xdrstdio_setpos(XDR * xdrs,u_int pos)144 xdrstdio_setpos(XDR *xdrs, u_int pos)
145 {
146
147 return ((fseeko((FILE *)xdrs->x_private, pos, SEEK_SET) == -1) ?
148 FALSE : TRUE);
149 }
150
151 static int32_t *
xdrstdio_inline(XDR * xdrs,u_int len)152 xdrstdio_inline(XDR *xdrs, u_int len)
153 {
154
155 /*
156 * Must do some work to implement this: must ensure
157 * enough data in the underlying stdio buffer,
158 * that the buffer is aligned so that we can indirect through a
159 * long *, and stuff this pointer in xdrs->x_buf. Doing
160 * a fread or fwrite to a scratch buffer would defeat
161 * most of the gains to be had here and require storage
162 * management on this buffer, so we don't do this.
163 */
164 return (NULL);
165 }
166