podman

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#include <dirent.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <unistd.h>
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#include <sys/select.h>
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static int open_files_max_fd;
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static fd_set *open_files_set;
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int
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is_fd_inherited(int fd)
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{
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  if (open_files_set == NULL || fd > open_files_max_fd || fd < 0)
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    return 0;
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  return FD_ISSET(fd % FD_SETSIZE, &(open_files_set[fd / FD_SETSIZE])) ? 1 : 0;
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}
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static void __attribute__((constructor)) init()
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{
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  /* Store how many FDs were open before the Go runtime kicked in.  */
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  DIR* d = opendir ("/dev/fd");
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  if (d)
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    {
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      struct dirent *ent;
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      size_t size = 0;
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      for (ent = readdir (d); ent; ent = readdir (d))
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        {
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          int fd;
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          if (ent->d_name[0] == '.')
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            continue;
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          fd = atoi (ent->d_name);
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          if (fd == dirfd (d)) {
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            continue;
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          }
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          if (fd >= size * FD_SETSIZE)
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            {
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              int i;
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              size_t new_size;
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              new_size = (fd / FD_SETSIZE) + 1;
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              open_files_set = realloc (open_files_set, new_size * sizeof (fd_set));
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              if (open_files_set == NULL)
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                _exit (EXIT_FAILURE);
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              for (i = size; i < new_size; i++)
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                FD_ZERO (&(open_files_set[i]));
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              size = new_size;
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            }
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          if (fd > open_files_max_fd) {
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            open_files_max_fd = fd;
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          }
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          FD_SET (fd % FD_SETSIZE, &(open_files_set[fd / FD_SETSIZE]));
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        }
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    }
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}
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