cdev/testdev.c

   1 /*
   2  * Compile with:
   3  * gcc testdev.c -o testdev -I /usr/src/sys -lprop -Wall -W -ansi
   4  */
   5
   6 #include <err.h>    /* for err() */
   7 #include <fcntl.h>
   8 #include <stdio.h>
   9 #include <stdlib.h>
  10 #include <string.h>
  11 #include <unistd.h>    /* for close() */
  12 #include <sys/ioctl.h>
  13 #include <sys/mydev.h>
  14 #include <prop/proplib.h>
  15
  16 int main(void)
  17 {
  18     char buffer[1000];
  19     struct mydev_params params;
  20     prop_dictionary_t pd;
  21     prop_string_t ps;
  22     int devfd, ret;
  23
  24     /* Open device */
  25     if ((devfd = open("/dev/mydev", O_RDONLY, 0)) < 0) {
  26         fprintf(stderr, "Failed to open /dev/mydev\n");
  27         exit(EXIT_FAILURE);
  28     }
  29
  30     /* Send ioctl request in the traditional way */
  31     params.number = 42;
  32     strncpy(params.string, "Hello World", MAX_STR);
  33
  34     if (ioctl(devfd, MYDEVOLDIOCTL, &params) == -1) {
  35         close(devfd);
  36         err(EXIT_FAILURE, "ioctl()");
  37     }
  38
  39     /* Create dictionary and add a <key, value> pair in it */
  40     pd = prop_dictionary_create();
  41     if (pd == NULL) {
  42         close(devfd);
  43         err(EXIT_FAILURE, "prop_dictionary_create()");
  44     }
  45
  46     ps = prop_string_create_cstring("value");
  47     if (ps == NULL) {
  48         close(devfd);
  49         prop_object_release(pd);
  50         err(EXIT_FAILURE, "prop_string_create_cstring()");
  51     }
  52
  53     if (prop_dictionary_set(pd, "key", ps) == false) {
  54         close(devfd);
  55         prop_object_release(ps);
  56         prop_object_release(pd);
  57         err(EXIT_FAILURE, "prop_dictionary_set()");
  58     }
  59
  60     prop_object_release(ps);
  61
  62     /* Send dictionary to kernel space */
  63     prop_dictionary_send_ioctl(pd, devfd, MYDEVSETPROPS);
  64
  65     prop_object_release(pd);
  66
  67     /* Read data from device */
  68     if ((ret = read(devfd, buffer, sizeof buffer)) < 0)
  69         err(EXIT_FAILURE, "read()");
  70
  71     printf("testdev: ret = %d, buffer = %s\n", ret, buffer);
  72
  73     /* Close device */
  74     if (close(devfd) == -1)
  75         err(EXIT_FAILURE, "close()");
  76
  77     return EXIT_SUCCESS;
  78 }