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