tools/testing/selftests/efivarfs/create-read.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 #include <stdio.h>
   3 #include <stdint.h>
   4 #include <stdlib.h>
   5 #include <unistd.h>
   6 #include <sys/types.h>
   7 #include <sys/stat.h>
   8 #include <fcntl.h>
   9 #include <errno.h>
  10 #include <string.h>
  11
  12 int main(int argc, char **argv)
  13 {
  14         const char *path;
  15         char buf[4];
  16         int fd, rc;
  17
  18         if (argc < 2) {
  19                 fprintf(stderr, "usage: %s <path>\n", argv[0]);
  20                 return EXIT_FAILURE;
  21         }
  22
  23         path = argv[1];
  24
  25         /* create a test variable */
  26         fd = open(path, O_RDWR | O_CREAT, 0600);
  27         if (fd < 0) {
  28                 perror("open(O_WRONLY)");
  29                 return EXIT_FAILURE;
  30         }
  31
  32         rc = read(fd, buf, sizeof(buf));
  33         if (rc != 0) {
  34                 fprintf(stderr, "Reading a new var should return EOF\n");
  35                 close(fd);
  36                 return EXIT_FAILURE;
  37         }
  38
  39         close(fd);
  40         return EXIT_SUCCESS;
  41 }