xref: /freebsd/sys/xdr/xdr_mem.c (revision 2e3f49888ec8851bafb22011533217487764fdb0)
1 /*	$NetBSD: xdr_mem.c,v 1.15 2000/01/22 22:19:18 mycroft Exp $	*/
2 
3 /*
4  * Sun RPC is a product of Sun Microsystems, Inc. and is provided for
5  * unrestricted use provided that this legend is included on all tape
6  * media and as a part of the software program in whole or part.  Users
7  * may copy or modify Sun RPC without charge, but are not authorized
8  * to license or distribute it to anyone else except as part of a product or
9  * program developed by the user.
10  *
11  * SUN RPC IS PROVIDED AS IS WITH NO WARRANTIES OF ANY KIND INCLUDING THE
12  * WARRANTIES OF DESIGN, MERCHANTIBILITY AND FITNESS FOR A PARTICULAR
13  * PURPOSE, OR ARISING FROM A COURSE OF DEALING, USAGE OR TRADE PRACTICE.
14  *
15  * Sun RPC is provided with no support and without any obligation on the
16  * part of Sun Microsystems, Inc. to assist in its use, correction,
17  * modification or enhancement.
18  *
19  * SUN MICROSYSTEMS, INC. SHALL HAVE NO LIABILITY WITH RESPECT TO THE
20  * INFRINGEMENT OF COPYRIGHTS, TRADE SECRETS OR ANY PATENTS BY SUN RPC
21  * OR ANY PART THEREOF.
22  *
23  * In no event will Sun Microsystems, Inc. be liable for any lost revenue
24  * or profits or other special, indirect and consequential damages, even if
25  * Sun has been advised of the possibility of such damages.
26  *
27  * Sun Microsystems, Inc.
28  * 2550 Garcia Avenue
29  * Mountain View, California  94043
30  */
31 
32 #include <sys/cdefs.h>
33 /*
34  * xdr_mem.h, XDR implementation using memory buffers.
35  *
36  * Copyright (C) 1984, Sun Microsystems, Inc.
37  *
38  * If you have some data to be interpreted as external data representation
39  * or to be converted to external data representation in a memory buffer,
40  * then this is the package for you.
41  *
42  */
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/malloc.h>
47 
48 #include <rpc/types.h>
49 #include <rpc/xdr.h>
50 
51 static void xdrmem_destroy(XDR *);
52 static bool_t xdrmem_getlong_aligned(XDR *, long *);
53 static bool_t xdrmem_putlong_aligned(XDR *, const long *);
54 static bool_t xdrmem_getlong_unaligned(XDR *, long *);
55 static bool_t xdrmem_putlong_unaligned(XDR *, const long *);
56 static bool_t xdrmem_getbytes(XDR *, char *, u_int);
57 static bool_t xdrmem_putbytes(XDR *, const char *, u_int);
58 /* XXX: w/64-bit pointers, u_int not enough! */
59 static u_int xdrmem_getpos(XDR *);
60 static bool_t xdrmem_setpos(XDR *, u_int);
61 static int32_t *xdrmem_inline_aligned(XDR *, u_int);
62 static int32_t *xdrmem_inline_unaligned(XDR *, u_int);
63 static bool_t xdrmem_control(XDR *xdrs, int request, void *info);
64 
65 static const struct	xdr_ops xdrmem_ops_aligned = {
66 	xdrmem_getlong_aligned,
67 	xdrmem_putlong_aligned,
68 	xdrmem_getbytes,
69 	xdrmem_putbytes,
70 	xdrmem_getpos,
71 	xdrmem_setpos,
72 	xdrmem_inline_aligned,
73 	xdrmem_destroy,
74 	xdrmem_control
75 };
76 
77 static const struct	xdr_ops xdrmem_ops_unaligned = {
78 	xdrmem_getlong_unaligned,
79 	xdrmem_putlong_unaligned,
80 	xdrmem_getbytes,
81 	xdrmem_putbytes,
82 	xdrmem_getpos,
83 	xdrmem_setpos,
84 	xdrmem_inline_unaligned,
85 	xdrmem_destroy,
86 	xdrmem_control
87 };
88 
89 /*
90  * The procedure xdrmem_create initializes a stream descriptor for a
91  * memory buffer.
92  */
93 void
94 xdrmem_create(XDR *xdrs, char *addr, u_int size, enum xdr_op op)
95 {
96 
97 	xdrs->x_op = op;
98 	xdrs->x_ops = ((unsigned long)addr & (sizeof(int32_t) - 1))
99 	    ? &xdrmem_ops_unaligned : &xdrmem_ops_aligned;
100 	xdrs->x_private = xdrs->x_base = addr;
101 	xdrs->x_handy = size;
102 }
103 
104 /*ARGSUSED*/
105 static void
106 xdrmem_destroy(XDR *xdrs)
107 {
108 
109 }
110 
111 static bool_t
112 xdrmem_getlong_aligned(XDR *xdrs, long *lp)
113 {
114 
115 	if (xdrs->x_handy < sizeof(int32_t))
116 		return (FALSE);
117 	xdrs->x_handy -= sizeof(int32_t);
118 	*lp = ntohl(*(uint32_t *)xdrs->x_private);
119 	xdrs->x_private = (char *)xdrs->x_private + sizeof(int32_t);
120 	return (TRUE);
121 }
122 
123 static bool_t
124 xdrmem_putlong_aligned(XDR *xdrs, const long *lp)
125 {
126 
127 	if (xdrs->x_handy < sizeof(int32_t))
128 		return (FALSE);
129 	xdrs->x_handy -= sizeof(int32_t);
130 	*(uint32_t *)xdrs->x_private = htonl((uint32_t)*lp);
131 	xdrs->x_private = (char *)xdrs->x_private + sizeof(int32_t);
132 	return (TRUE);
133 }
134 
135 static bool_t
136 xdrmem_getlong_unaligned(XDR *xdrs, long *lp)
137 {
138 	uint32_t l;
139 
140 	if (xdrs->x_handy < sizeof(int32_t))
141 		return (FALSE);
142 	xdrs->x_handy -= sizeof(int32_t);
143 	memmove(&l, xdrs->x_private, sizeof(int32_t));
144 	*lp = ntohl(l);
145 	xdrs->x_private = (char *)xdrs->x_private + sizeof(int32_t);
146 	return (TRUE);
147 }
148 
149 static bool_t
150 xdrmem_putlong_unaligned(XDR *xdrs, const long *lp)
151 {
152 	uint32_t l;
153 
154 	if (xdrs->x_handy < sizeof(int32_t))
155 		return (FALSE);
156 	xdrs->x_handy -= sizeof(int32_t);
157 	l = htonl((uint32_t)*lp);
158 	memmove(xdrs->x_private, &l, sizeof(int32_t));
159 	xdrs->x_private = (char *)xdrs->x_private + sizeof(int32_t);
160 	return (TRUE);
161 }
162 
163 static bool_t
164 xdrmem_getbytes(XDR *xdrs, char *addr, u_int len)
165 {
166 
167 	if (xdrs->x_handy < len)
168 		return (FALSE);
169 	xdrs->x_handy -= len;
170 	memmove(addr, xdrs->x_private, len);
171 	xdrs->x_private = (char *)xdrs->x_private + len;
172 	return (TRUE);
173 }
174 
175 static bool_t
176 xdrmem_putbytes(XDR *xdrs, const char *addr, u_int len)
177 {
178 
179 	if (xdrs->x_handy < len)
180 		return (FALSE);
181 	xdrs->x_handy -= len;
182 	memmove(xdrs->x_private, addr, len);
183 	xdrs->x_private = (char *)xdrs->x_private + len;
184 	return (TRUE);
185 }
186 
187 static u_int
188 xdrmem_getpos(XDR *xdrs)
189 {
190 
191 	/* XXX w/64-bit pointers, u_int not enough! */
192 	return (u_int)((u_long)xdrs->x_private - (u_long)xdrs->x_base);
193 }
194 
195 static bool_t
196 xdrmem_setpos(XDR *xdrs, u_int pos)
197 {
198 	char *newaddr = xdrs->x_base + pos;
199 	char *lastaddr = (char *)xdrs->x_private + xdrs->x_handy;
200 
201 	if (newaddr > lastaddr)
202 		return (FALSE);
203 	xdrs->x_private = newaddr;
204 	xdrs->x_handy = (u_int)(lastaddr - newaddr); /* XXX sizeof(u_int) <? sizeof(ptrdiff_t) */
205 	return (TRUE);
206 }
207 
208 static int32_t *
209 xdrmem_inline_aligned(XDR *xdrs, u_int len)
210 {
211 	int32_t *buf = NULL;
212 
213 	if (xdrs->x_handy >= len) {
214 		xdrs->x_handy -= len;
215 		buf = (int32_t *)xdrs->x_private;
216 		xdrs->x_private = (char *)xdrs->x_private + len;
217 	}
218 	return (buf);
219 }
220 
221 /* ARGSUSED */
222 static int32_t *
223 xdrmem_inline_unaligned(XDR *xdrs, u_int len)
224 {
225 
226 	return (0);
227 }
228 
229 static bool_t
230 xdrmem_control(XDR *xdrs, int request, void *info)
231 {
232 	xdr_bytesrec *xptr;
233 	int32_t *l;
234 	int len;
235 
236 	switch (request) {
237 	case XDR_GET_BYTES_AVAIL:
238 		xptr = (xdr_bytesrec *)info;
239 		xptr->xc_is_last_record = TRUE;
240 		xptr->xc_num_avail = xdrs->x_handy;
241 		return (TRUE);
242 
243 	case XDR_PEEK:
244 		/*
245 		 * Return the next 4 byte unit in the XDR stream.
246 		 */
247 		if (xdrs->x_handy < sizeof (int32_t))
248 			return (FALSE);
249 		l = (int32_t *)info;
250 		*l = (int32_t)ntohl((uint32_t)
251 		    (*((int32_t *)(xdrs->x_private))));
252 		return (TRUE);
253 
254 	case XDR_SKIPBYTES:
255 		/*
256 		 * Skip the next N bytes in the XDR stream.
257 		 */
258 		l = (int32_t *)info;
259 		len = RNDUP((int)(*l));
260 		if (xdrs->x_handy < len)
261 			return (FALSE);
262 		xdrs->x_handy -= len;
263 		xdrs->x_private = (char *)xdrs->x_private + len;
264 		return (TRUE);
265 	}
266 	return (FALSE);
267 }
268