1*da6c28aaSamw /*
2*da6c28aaSamw * CDDL HEADER START
3*da6c28aaSamw *
4*da6c28aaSamw * The contents of this file are subject to the terms of the
5*da6c28aaSamw * Common Development and Distribution License (the "License").
6*da6c28aaSamw * You may not use this file except in compliance with the License.
7*da6c28aaSamw *
8*da6c28aaSamw * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9*da6c28aaSamw * or http://www.opensolaris.org/os/licensing.
10*da6c28aaSamw * See the License for the specific language governing permissions
11*da6c28aaSamw * and limitations under the License.
12*da6c28aaSamw *
13*da6c28aaSamw * When distributing Covered Code, include this CDDL HEADER in each
14*da6c28aaSamw * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15*da6c28aaSamw * If applicable, add the following below this CDDL HEADER, with the
16*da6c28aaSamw * fields enclosed by brackets "[]" replaced with your own identifying
17*da6c28aaSamw * information: Portions Copyright [yyyy] [name of copyright owner]
18*da6c28aaSamw *
19*da6c28aaSamw * CDDL HEADER END
20*da6c28aaSamw */
21*da6c28aaSamw /*
22*da6c28aaSamw * Copyright 2007 Sun Microsystems, Inc. All rights reserved.
23*da6c28aaSamw * Use is subject to license terms.
24*da6c28aaSamw */
25*da6c28aaSamw
26*da6c28aaSamw /*
27*da6c28aaSamw * Buffer manipulation routines. These routines can be used to format
28*da6c28aaSamw * data within a data buffer without worrying about overrunning the
29*da6c28aaSamw * buffer.
30*da6c28aaSamw *
31*da6c28aaSamw * A ctxbuf_t structure is used to track the current location within
32*da6c28aaSamw * the buffer. The ctxbuf_init() must be called first to initialize the
33*da6c28aaSamw * context structure. ctxbuf_printf() can then be called to fill the buffer.
34*da6c28aaSamw * ctxbuf_printf will discard any data that would overrun the buffer and
35*da6c28aaSamw * the buffer will always be null terminated.
36*da6c28aaSamw */
37*da6c28aaSamw
38*da6c28aaSamw #pragma ident "%Z%%M% %I% %E% SMI"
39*da6c28aaSamw
40*da6c28aaSamw #include <stdio.h>
41*da6c28aaSamw #include <stdarg.h>
42*da6c28aaSamw #include <smbsrv/libsmb.h>
43*da6c28aaSamw
44*da6c28aaSamw /*
45*da6c28aaSamw * smb_ctxbuf_init
46*da6c28aaSamw *
47*da6c28aaSamw * Initialize the buffer context structure.
48*da6c28aaSamw * This must be called before any of the other
49*da6c28aaSamw * buffer routines can be used.
50*da6c28aaSamw *
51*da6c28aaSamw * Returns -1 if invalid parameters, 0 otherwise
52*da6c28aaSamw */
53*da6c28aaSamw int
smb_ctxbuf_init(smb_ctxbuf_t * ctx,unsigned char * buf,size_t buflen)54*da6c28aaSamw smb_ctxbuf_init(smb_ctxbuf_t *ctx, unsigned char *buf, size_t buflen)
55*da6c28aaSamw {
56*da6c28aaSamw if (ctx == 0 || buf == 0 || buflen == 0)
57*da6c28aaSamw return (-1);
58*da6c28aaSamw
59*da6c28aaSamw buf[0] = '\0';
60*da6c28aaSamw
61*da6c28aaSamw ctx->basep = buf;
62*da6c28aaSamw ctx->curp = buf;
63*da6c28aaSamw ctx->endp = &buf[buflen];
64*da6c28aaSamw
65*da6c28aaSamw return (0);
66*da6c28aaSamw }
67*da6c28aaSamw
68*da6c28aaSamw /*
69*da6c28aaSamw * smb_ctxbuf_len
70*da6c28aaSamw *
71*da6c28aaSamw * Return the amount of data stored in the buffer,
72*da6c28aaSamw * excluding the terminating null character. Similar
73*da6c28aaSamw * to strlen()
74*da6c28aaSamw *
75*da6c28aaSamw * Returns 0 if the ctx is invalid.
76*da6c28aaSamw */
77*da6c28aaSamw int
smb_ctxbuf_len(smb_ctxbuf_t * ctx)78*da6c28aaSamw smb_ctxbuf_len(smb_ctxbuf_t *ctx)
79*da6c28aaSamw {
80*da6c28aaSamw if (ctx == 0 || ctx->basep == 0 ||
81*da6c28aaSamw ctx->curp == 0 || ctx->endp == 0)
82*da6c28aaSamw return (0);
83*da6c28aaSamw else
84*da6c28aaSamw /*LINTED E_PTRDIFF_OVERFLOW*/
85*da6c28aaSamw return (ctx->curp - ctx->basep);
86*da6c28aaSamw }
87*da6c28aaSamw
88*da6c28aaSamw /*
89*da6c28aaSamw * smb_ctxbuf_printf
90*da6c28aaSamw *
91*da6c28aaSamw * Move formatted output (based on fmt string) to the buffer
92*da6c28aaSamw * identified in ctxbuf. Any output characters beyond the buffer
93*da6c28aaSamw * are discarded and a null character is written at the end of the
94*da6c28aaSamw * characters actually written.
95*da6c28aaSamw *
96*da6c28aaSamw * Returns
97*da6c28aaSamw * Always return the number of bytes actually written (excluding the
98*da6c28aaSamw * terminating null).
99*da6c28aaSamw */
100*da6c28aaSamw int
smb_ctxbuf_printf(smb_ctxbuf_t * ctx,const char * fmt,...)101*da6c28aaSamw smb_ctxbuf_printf(smb_ctxbuf_t *ctx, const char *fmt, ...)
102*da6c28aaSamw {
103*da6c28aaSamw int n;
104*da6c28aaSamw va_list args;
105*da6c28aaSamw
106*da6c28aaSamw if (ctx == 0 || ctx->basep == 0 ||
107*da6c28aaSamw ctx->curp == 0 || ctx->endp == 0)
108*da6c28aaSamw return (-1);
109*da6c28aaSamw
110*da6c28aaSamw va_start(args, fmt);
111*da6c28aaSamw /*LINTED E_PTRDIFF_OVERFLOW*/
112*da6c28aaSamw n = vsnprintf((char *)ctx->curp, ctx->endp-ctx->curp, fmt, args);
113*da6c28aaSamw ctx->curp += n;
114*da6c28aaSamw va_end(args);
115*da6c28aaSamw
116*da6c28aaSamw /*
117*da6c28aaSamw * return the number of bytes moved into the buffer.
118*da6c28aaSamw */
119*da6c28aaSamw return (n);
120*da6c28aaSamw }
121