src/getdents64.c

   1 /* $Id$ */
   2
   3 #define _GNU_SOURCE 1
   4
   5 #include <stdio.h>
   6 #include <stdlib.h>
   7 #include <sys/types.h>
   8 #include <sys/stat.h>
   9 #include <fcntl.h>
  10 #include <dirent.h>
  11 #include <unistd.h>
  12 #include <assert.h>
  13 #include <linux/unistd.h>
  14 #include <string.h>
  15
  16
  17 static _syscall3(long, getdents64, uint, fd, struct dirent64 *, dirp, uint, count);
  18
  19 int main(int argc,char **argv)
  20 {
  21 int fd;
  22
  23         if (argc!=2) {
  24                 fprintf(stderr,"Required directory name argument!\n");
  25                 exit(EXIT_FAILURE);
  26                 }
  27         if (-1==(fd=open(argv[1],O_RDONLY /* |O_DIRECTORY */))) {
  28                 fprintf(stderr,"open(\"%s\"): %m\n",argv[1]);
  29                 exit(EXIT_FAILURE);
  30                 }
  31         for (;;) {
  32 off_t off;
  33 char buf[100];
  34 struct dirent64 *dirent64;
  35 int got;
  36
  37                 if ((off_t)-1==(off=lseek(fd,0,SEEK_CUR))) {
  38                         fprintf(stderr,"lseek(): %m\n");
  39                         exit(EXIT_FAILURE);
  40                 }
  41                 printf("@=%lld\n",(long long)off);
  42                 memset(buf,0,sizeof(buf));
  43                 got=getdents64(fd,(void *)buf,sizeof(buf));
  44                 printf("got=%d\n",got);
  45                 if (got==-1)
  46                         perror("getdents()");
  47                 assert(got<=sizeof(buf));
  48                 if (!got)
  49                         break;
  50                 for (
  51                                 dirent64=(void *)buf;
  52                                 (char *)dirent64<buf+got;
  53                                 dirent64=(void *)((char *)dirent64+dirent64->d_reclen)
  54                                 ) {
  55                         printf("dirent64_rel=%d, d_off=0x%llx; d_ino=%llu, d_reclen=%u, d_type=%u, d_name=%s\n",
  56                                         (char *)dirent64-buf,
  57                                         (long long)dirent64->d_off,(unsigned long long)dirent64->d_ino,
  58                                         (unsigned)dirent64->d_reclen,
  59                                         (unsigned)dirent64->d_type,dirent64->d_name);
  60                         }
  61                 printf("trailing=%d\n",(buf+got)-(char *)dirent64);
  62                 }
  63         puts("done");
  64         return EXIT_SUCCESS;
  65 }