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 34void 35cuio_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 67void 68cuio_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 101int 102cuio_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 126int 127cuio_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