lkmpg/examples/hello-5.c
linD026 eef2bc4395
Enforce Linux kernel coding style (#88)
The only exception is to indent with four spaces rather than tabs
for sticking to compact layout of source listing.

Close #87
2021-09-02 15:15:07 +08:00

68 lines
2.1 KiB
C

/*
* hello-5.c - Demonstrates command line argument passing to a module.
*/
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/stat.h>
MODULE_LICENSE("GPL");
static short int myshort = 1;
static int myint = 420;
static long int mylong = 9999;
static char *mystring = "blah";
static int myintarray[2] = { 420, 420 };
static int arr_argc = 0;
/* module_param(foo, int, 0000)
* The first param is the parameters name.
* The second param is its data type.
* The final argument is the permissions bits,
* for exposing parameters in sysfs (if non-zero) at a later stage.
*/
module_param(myshort, short, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
MODULE_PARM_DESC(myshort, "A short integer");
module_param(myint, int, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
MODULE_PARM_DESC(myint, "An integer");
module_param(mylong, long, S_IRUSR);
MODULE_PARM_DESC(mylong, "A long integer");
module_param(mystring, charp, 0000);
MODULE_PARM_DESC(mystring, "A character string");
/* module_param_array(name, type, num, perm);
* The first param is the parameter's (in this case the array's) name.
* The second param is the data type of the elements of the array.
* The third argument is a pointer to the variable that will store the number.
* of elements of the array initialized by the user at module loading time.
* The fourth argument is the permission bits.
*/
module_param_array(myintarray, int, &arr_argc, 0000);
MODULE_PARM_DESC(myintarray, "An array of integers");
static int __init hello_5_init(void)
{
int i;
pr_info("Hello, world 5\n=============\n");
pr_info("myshort is a short integer: %hd\n", myshort);
pr_info("myint is an integer: %d\n", myint);
pr_info("mylong is a long integer: %ld\n", mylong);
pr_info("mystring is a string: %s\n", mystring);
for (i = 0; i < ARRAY_SIZE(myintarray); i++)
pr_info("myintarray[%d] = %d\n", i, myintarray[i]);
pr_info("got %d arguments for myintarray.\n", arr_argc);
return 0;
}
static void __exit hello_5_exit(void)
{
pr_info("Goodbye, world 5\n");
}
module_init(hello_5_init);
module_exit(hello_5_exit);