commands/dev2name/dev2name.c

   1
   2 /* Translate internal FS device number to a /dev/ name. */
   3
   4 #include <stdio.h>
   5 #include <string.h>
   6 #include <stdlib.h>
   7 #include <dirent.h>
   8 #include <unistd.h>
   9
  10 #include <sys/stat.h>
  11 #include <sys/types.h>
  12 #include <minix/config.h>
  13 #include <minix/const.h>
  14
  15 #define PATH_DEV "/dev"
  16
  17 int
  18 main(int argc, char *argv[])
  19 {
  20         DIR *dev;
  21         struct dirent *e;
  22         int dev_n;
  23         if(argc <= 1 || argc > 3) {
  24                 fprintf(stderr, "Usage: \n"
  25                         "%s <major> <minor>\n"
  26                         "%s <devicenumber>\n", argv[0], argv[0]);
  27                 return 1;
  28         } else if(argc == 2) dev_n = atoi(argv[1]);
  29         else if(argc == 3) dev_n = (atoi(argv[1]) << MAJOR) | atoi(argv[2]);
  30
  31         if(chdir(PATH_DEV) < 0) {
  32                 perror(PATH_DEV " chdir");
  33                 return 1;
  34         }
  35
  36         if(!(dev=opendir("."))) {
  37                 perror(". in " PATH_DEV);
  38                 return 1;
  39         }
  40
  41         while((e=readdir(dev))) {
  42                 struct stat st;
  43                 if(stat(e->d_name, &st) < 0) {
  44                         continue;
  45                 }
  46                 if((st.st_mode & (S_IFBLK | S_IFCHR)) && dev_n == st.st_rdev) {
  47                         printf("%s/%s\n", PATH_DEV, e->d_name);
  48                         return 0;
  49                 }
  50         }
  51
  52         return 1;
  53 }
  54