/* 08 Nov 1998*/ /* * cdev.c * * 08 Nov 1998 Rajesh Vaidheeswarran * * Copyright (c) 1998 Rajesh Vaidheeswarran * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by Rajesh Vaidheeswarran. * 4. The name Rajesh Vaidheeswarran may not be used to endorse or promote * products derived from this software without specific prior written * permission. * * THIS SOFTWARE IS PROVIDED BY RAJESH VAIDHEESWARRAN ``AS IS'' AND ANY * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE RAJESH VAIDHEESWARRAN BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * Copyright (c) 1993 Terrence R. Lambert. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by Terrence R. Lambert. * 4. The name Terrence R. Lambert may not be used to endorse or promote * products derived from this software without specific prior written * permission. * * THIS SOFTWARE IS PROVIDED BY TERRENCE R. LAMBERT ``AS IS'' AND ANY * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE TERRENCE R. LAMBERT BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * * $FreeBSD: src/share/examples/kld/cdev/module/cdev.c,v 1.3.2.1 2000/10/25 09:02:34 sobomax Exp $ */ #include #include #include #include #include #include #include #include #include "cdev.h" /* * This is the actual code for the system call... it can't be static because * it is exported to another part of the module... the only place it needs * to be referenced is the sysent we are interested in. * * To write your own system call using this as a template, you could strip * out this code and use the rest as a prototype module, changing only the * function names and the number of arguments to the call in the module * specific "sysent". * * You would have to use the "-R" option of "ld" to ensure a linkable file * if you were to do this, since you would need to combine multiple ".o" * files into a single ".o" file for use by "modload". */ #define CDEV_IOCTL1 _IOR('C', 1, u_int) /* Stores string recv'd by _write() */ static char buf[512+1]; static size_t len; int mydev_open(struct dev_open_args *args) { kprintf("mydev_open: dev_t=%d, flags=%x, type=%x\n", devid_from_dev(args->a_head.a_dev), args->a_oflags, args->a_devtype); memset(&buf, '\0', 513); len = 0; return (0); } int mydev_close(struct dev_close_args *args) { kprintf("mydev_close: dev_t=%d, flags=%x, type=%x\n", devid_from_dev(args->a_head.a_dev), args->a_fflag, args->a_devtype); return (0); } int mydev_ioctl(struct dev_ioctl_args *args) { int error = 0; kprintf("mydev_ioctl: dev_t=%d, cmd=%lx, arg=%p, mode=%x\n", devid_from_dev(args->a_head.a_dev), args->a_cmd, args->a_data, args->a_fflag); switch(args->a_cmd) { case CDEV_IOCTL1: kprintf("you called mydev_ioctl CDEV_IOCTL1\n"); break; default: kprintf("No such ioctl for me!\n"); error = EINVAL; break; } return (error); } /* * mydev_write takes in a character string and saves it * to buf for later accessing. */ int mydev_write(struct dev_write_args *args) { int err = 0; kprintf("mydev_write: dev_t=%d, uio=%p, ioflag=%d\n", devid_from_dev(args->a_head.a_dev), args->a_uio, args->a_ioflag); err = copyinstr(args->a_uio->uio_iov->iov_base, &buf, 512, &len); if (err != 0) { kprintf("Write to \"cdev\" failed.\n"); } return (err); } /* * The mydev_read function just takes the buf that was saved * via mydev_write() and returns it to userland for * accessing. */ int mydev_read(struct dev_read_args *args) { int err = 0; kprintf("mydev_read: dev_t=%d, uio=%p, ioflag=%d\n", devid_from_dev(args->a_head.a_dev), args->a_uio, args->a_ioflag); if (len <= 0) { err = -1; } else { /* copy buf to userland */ copystr(&buf, args->a_uio->uio_iov->iov_base, 513, &len); } return (err); }