1 /* $OpenBSD: criov.c,v 1.20 2015/03/14 03:38:46 jsg Exp $ */
2
3 /*
4 * Copyright (c) 1999 Theo de Raadt
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 *
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28 #include <sys/param.h>
29 #include <sys/systm.h>
30 #include <sys/errno.h>
31 #include <sys/kernel.h>
32 #include <sys/mbuf.h>
33
34 void
cuio_copydata(struct uio * uio,int off,int len,caddr_t cp)35 cuio_copydata(struct uio *uio, int off, int len, caddr_t cp)
36 {
37 struct iovec *iov = uio->uio_iov;
38 int iol = uio->uio_iovcnt;
39 unsigned count;
40
41 if (off < 0)
42 panic("cuio_copydata: off %d < 0", off);
43 if (len < 0)
44 panic("cuio_copydata: len %d < 0", len);
45 while (off > 0) {
46 if (iol == 0)
47 panic("iov_copydata: empty in skip");
48 if (off < iov->iov_len)
49 break;
50 off -= iov->iov_len;
51 iol--;
52 iov++;
53 }
54 while (len > 0) {
55 if (iol == 0)
56 panic("cuio_copydata: empty");
57 count = min(iov->iov_len - off, len);
58 bcopy(((caddr_t)iov->iov_base) + off, cp, count);
59 len -= count;
60 cp += count;
61 off = 0;
62 iol--;
63 iov++;
64 }
65 }
66
67 void
cuio_copyback(struct uio * uio,int off,int len,const void * _cp)68 cuio_copyback(struct uio *uio, int off, int len, const void *_cp)
69 {
70 struct iovec *iov = uio->uio_iov;
71 int iol = uio->uio_iovcnt;
72 unsigned count;
73 caddr_t cp = (caddr_t)_cp;
74
75 if (off < 0)
76 panic("cuio_copyback: off %d < 0", off);
77 if (len < 0)
78 panic("cuio_copyback: len %d < 0", len);
79 while (off > 0) {
80 if (iol == 0)
81 panic("cuio_copyback: empty in skip");
82 if (off < iov->iov_len)
83 break;
84 off -= iov->iov_len;
85 iol--;
86 iov++;
87 }
88 while (len > 0) {
89 if (iol == 0)
90 panic("uio_copyback: empty");
91 count = min(iov->iov_len - off, len);
92 bcopy(cp, ((caddr_t)iov->iov_base) + off, count);
93 len -= count;
94 cp += count;
95 off = 0;
96 iol--;
97 iov++;
98 }
99 }
100
101 int
cuio_getptr(struct uio * uio,int loc,int * off)102 cuio_getptr(struct uio *uio, int loc, int *off)
103 {
104 int ind, len;
105
106 ind = 0;
107 while (loc >= 0 && ind < uio->uio_iovcnt) {
108 len = uio->uio_iov[ind].iov_len;
109 if (len > loc) {
110 *off = loc;
111 return (ind);
112 }
113 loc -= len;
114 ind++;
115 }
116
117 if (ind > 0 && loc == 0) {
118 ind--;
119 *off = uio->uio_iov[ind].iov_len;
120 return (ind);
121 }
122
123 return (-1);
124 }
125
126 int
cuio_apply(struct uio * uio,int off,int len,int (* f)(caddr_t,caddr_t,unsigned int),caddr_t fstate)127 cuio_apply(struct uio *uio, int off, int len,
128 int (*f)(caddr_t, caddr_t, unsigned int), caddr_t fstate)
129 {
130 int rval, ind, uiolen;
131 unsigned int count;
132
133 if (len < 0)
134 panic("cuio_apply: len %d < 0", len);
135 if (off < 0)
136 panic("cuio_apply: off %d < 0", off);
137
138 ind = 0;
139 while (off > 0) {
140 if (ind >= uio->uio_iovcnt)
141 panic("cuio_apply: ind %d >= uio_iovcnt %d for off",
142 ind, uio->uio_iovcnt);
143 uiolen = uio->uio_iov[ind].iov_len;
144 if (off < uiolen)
145 break;
146 off -= uiolen;
147 ind++;
148 }
149 while (len > 0) {
150 if (ind >= uio->uio_iovcnt)
151 panic("cuio_apply: ind %d >= uio_iovcnt %d for len",
152 ind, uio->uio_iovcnt);
153 count = min(uio->uio_iov[ind].iov_len - off, len);
154
155 rval = f(fstate, (char *)uio->uio_iov[ind].iov_base + off,
156 count);
157 if (rval)
158 return (rval);
159
160 len -= count;
161 off = 0;
162 ind++;
163 }
164
165 return (0);
166 }
167