1/* 08 Nov 1998*/ 2/*- 3 * cdev.c 4 * 5 * 08 Nov 1998 Rajesh Vaidheeswarran 6 * 7 * SPDX-License-Identifier: BSD-4-Clause 8 * 9 * Copyright (c) 1998 Rajesh Vaidheeswarran 10 * All rights reserved. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by Rajesh Vaidheeswarran. 23 * 4. The name Rajesh Vaidheeswarran may not be used to endorse or promote 24 * products derived from this software without specific prior written 25 * permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY RAJESH VAIDHEESWARRAN ``AS IS'' AND ANY 28 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 29 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 30 * ARE DISCLAIMED. IN NO EVENT SHALL THE RAJESH VAIDHEESWARRAN BE LIABLE 31 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 32 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 33 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 34 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 35 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 36 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 37 * SUCH DAMAGE. 38 * 39 * Copyright (c) 1993 Terrence R. Lambert. 40 * All rights reserved. 41 * 42 * Redistribution and use in source and binary forms, with or without 43 * modification, are permitted provided that the following conditions 44 * are met: 45 * 1. Redistributions of source code must retain the above copyright 46 * notice, this list of conditions and the following disclaimer. 47 * 2. Redistributions in binary form must reproduce the above copyright 48 * notice, this list of conditions and the following disclaimer in the 49 * documentation and/or other materials provided with the distribution. 50 * 3. All advertising materials mentioning features or use of this software 51 * must display the following acknowledgement: 52 * This product includes software developed by Terrence R. Lambert. 53 * 4. The name Terrence R. Lambert may not be used to endorse or promote 54 * products derived from this software without specific prior written 55 * permission. 56 * 57 * THIS SOFTWARE IS PROVIDED BY TERRENCE R. LAMBERT ``AS IS'' AND ANY 58 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 59 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 60 * ARE DISCLAIMED. IN NO EVENT SHALL THE TERRENCE R. LAMBERT BE LIABLE 61 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 62 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 63 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 64 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 65 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 66 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 67 * SUCH DAMAGE. 68 * 69 * 70 * $FreeBSD$ 71 */ 72#include <sys/param.h> 73#include <sys/uio.h> 74#include <sys/proc.h> 75#include <sys/systm.h> 76#include <sys/ioccom.h> 77#include <sys/conf.h> 78 79#include "cdev.h" 80 81/* 82 * This is the actual code for the system call... it can't be static because 83 * it is exported to another part of the module... the only place it needs 84 * to be referenced is the sysent we are interested in. 85 * 86 * To write your own system call using this as a template, you could strip 87 * out this code and use the rest as a prototype module, changing only the 88 * function names and the number of arguments to the call in the module 89 * specific "sysent". 90 * 91 * You would have to use the "-R" option of "ld" to ensure a linkable file 92 * if you were to do this, since you would need to combine multiple ".o" 93 * files into a single ".o" file for use by "modload". 94 */ 95 96#define CDEV_IOCTL1 _IOR('C', 1, u_int) 97 98/* Stores string recv'd by _write() */ 99static char buf[512+1]; 100static size_t len; 101 102int 103mydev_open(struct cdev *dev, int flag, int otyp, struct thread *td) 104{ 105 struct proc *procp = td->td_proc; 106 107 printf("mydev_open: dev_t=%lu, flag=%x, otyp=%x, procp=%p\n", 108 dev2udev(dev), flag, otyp, procp); 109 memset(&buf, '\0', 513); 110 len = 0; 111 return (0); 112} 113 114int 115mydev_close(struct cdev *dev, int flag, int otyp, struct thread *td) 116{ 117 struct proc *procp = td->td_proc; 118 119 printf("mydev_close: dev_t=%lu, flag=%x, otyp=%x, procp=%p\n", 120 dev2udev(dev), flag, otyp, procp); 121 return (0); 122} 123 124int 125mydev_ioctl(struct cdev *dev, u_long cmd, caddr_t arg, int mode, 126 struct thread *td) 127{ 128 int error = 0; 129 struct proc *procp = td->td_proc; 130 131 printf("mydev_ioctl: dev_t=%lu, cmd=%lx, arg=%p, mode=%x procp=%p\n", 132 dev2udev(dev), cmd, arg, mode, procp); 133 134 switch(cmd) { 135 case CDEV_IOCTL1: 136 printf("you called mydev_ioctl CDEV_IOCTL1\n"); 137 break; 138 default: 139 printf("No such ioctl for me!\n"); 140 error = EINVAL; 141 break; 142 } 143 return (error); 144} 145 146/* 147 * mydev_write takes in a character string and saves it 148 * to buf for later accessing. 149 */ 150int 151mydev_write(struct cdev *dev, struct uio *uio, int ioflag) 152{ 153 int err = 0; 154 155 printf("mydev_write: dev_t=%lu, uio=%p, ioflag=%d\n", 156 dev2udev(dev), uio, ioflag); 157 158 err = copyinstr(uio->uio_iov->iov_base, &buf, 512, &len); 159 if (err != 0) { 160 printf("Write to \"cdev\" failed.\n"); 161 } 162 return(err); 163} 164 165/* 166 * The mydev_read function just takes the buf that was saved 167 * via mydev_write() and returns it to userland for 168 * accessing. 169 */ 170int 171mydev_read(struct cdev *dev, struct uio *uio, int ioflag) 172{ 173 int err = 0; 174 175 printf("mydev_read: dev_t=%lu, uio=%p, ioflag=%d\n", 176 dev2udev(dev), uio, ioflag); 177 178 if (len <= 0) { 179 err = -1; 180 } else { /* copy buf to userland */ 181 copystr(&buf, uio->uio_iov->iov_base, 513, &len); 182 } 183 return(err); 184} 185