LXR linux/tools/lib/api/fd/array.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef __API_FD_ARRAY__
   3#define __API_FD_ARRAY__
   4
   5#include <stdio.h>
   6
   7struct pollfd;
   8
   9/**
  10 * struct fdarray: Array of file descriptors
  11 *
  12 * @priv: Per array entry priv area, users should access just its contents,
  13 *        not set it to anything, as it is kept in synch with @entries, being
  14 *        realloc'ed, * for instance, in fdarray__{grow,filter}.
  15 *
  16 *        I.e. using 'fda->priv[N].idx = * value' where N < fda->nr is ok,
  17 *        but doing 'fda->priv = malloc(M)' is not allowed.
  18 */
  19struct fdarray {
  20        int            nr;
  21        int            nr_alloc;
  22        int            nr_autogrow;
  23        struct pollfd *entries;
  24        union {
  25                int    idx;
  26                void   *ptr;
  27        } *priv;
  28};
  29
  30void fdarray__init(struct fdarray *fda, int nr_autogrow);
  31void fdarray__exit(struct fdarray *fda);
  32
  33struct fdarray *fdarray__new(int nr_alloc, int nr_autogrow);
  34void fdarray__delete(struct fdarray *fda);
  35
  36int fdarray__add(struct fdarray *fda, int fd, short revents);
  37int fdarray__poll(struct fdarray *fda, int timeout);
  38int fdarray__filter(struct fdarray *fda, short revents,
  39                    void (*entry_destructor)(struct fdarray *fda, int fd, void *arg),
  40                    void *arg);
  41int fdarray__grow(struct fdarray *fda, int extra);
  42int fdarray__fprintf(struct fdarray *fda, FILE *fp);
  43
  44static inline int fdarray__available_entries(struct fdarray *fda)
  45{
  46        return fda->nr_alloc - fda->nr;
  47}
  48
  49#endif /* __API_FD_ARRAY__ */
  50