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Diffstat (limited to 'share/examples/kld/cdev/module/cdev.c')
| -rw-r--r-- | share/examples/kld/cdev/module/cdev.c | 182 |
1 files changed, 182 insertions, 0 deletions
diff --git a/share/examples/kld/cdev/module/cdev.c b/share/examples/kld/cdev/module/cdev.c new file mode 100644 index 000000000000..dda63c4fa70e --- /dev/null +++ b/share/examples/kld/cdev/module/cdev.c @@ -0,0 +1,182 @@ +/* 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. + * + * + * $FreeBSD$ + */ +#include <sys/param.h> +#include <sys/uio.h> +#include <sys/proc.h> +#include <sys/systm.h> +#include <sys/ioccom.h> +#include <sys/conf.h> + +#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 cdev *dev, int flag, int otyp, struct thread *td) +{ + struct proc *procp = td->td_proc; + + printf("mydev_open: dev_t=%d, flag=%x, otyp=%x, procp=%p\n", + dev2udev(dev), flag, otyp, procp); + memset(&buf, '\0', 513); + len = 0; + return (0); +} + +int +mydev_close(struct cdev *dev, int flag, int otyp, struct thread *td) +{ + struct proc *procp = td->td_proc; + + printf("mydev_close: dev_t=%d, flag=%x, otyp=%x, procp=%p\n", + dev2udev(dev), flag, otyp, procp); + return (0); +} + +int +mydev_ioctl(struct cdev *dev, u_long cmd, caddr_t arg, int mode, + struct thread *td) +{ + int error = 0; + struct proc *procp = td->td_proc; + + printf("mydev_ioctl: dev_t=%d, cmd=%lx, arg=%p, mode=%x procp=%p\n", + dev2udev(dev), cmd, arg, mode, procp); + + switch(cmd) { + case CDEV_IOCTL1: + printf("you called mydev_ioctl CDEV_IOCTL1\n"); + break; + default: + printf("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 cdev *dev, struct uio *uio, int ioflag) +{ + int err = 0; + + printf("mydev_write: dev_t=%d, uio=%p, ioflag=%d\n", + dev2udev(dev), uio, ioflag); + + err = copyinstr(uio->uio_iov->iov_base, &buf, 512, &len); + if (err != 0) { + printf("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 cdev *dev, struct uio *uio, int ioflag) +{ + int err = 0; + + printf("mydev_read: dev_t=%d, uio=%p, ioflag=%d\n", + dev2udev(dev), uio, ioflag); + + if (len <= 0) { + err = -1; + } else { /* copy buf to userland */ + copystr(&buf, uio->uio_iov->iov_base, 513, &len); + } + return(err); +} |