xref: /openbmc/linux/tools/lib/api/fd/array.h (revision 3c6a73cc)
1 #ifndef __API_FD_ARRAY__
2 #define __API_FD_ARRAY__
3 
4 #include <stdio.h>
5 
6 struct pollfd;
7 
8 /**
9  * struct fdarray: Array of file descriptors
10  *
11  * @priv: Per array entry priv area, users should access just its contents,
12  *	  not set it to anything, as it is kept in synch with @entries, being
13  *	  realloc'ed, * for instance, in fdarray__{grow,filter}.
14  *
15  *	  I.e. using 'fda->priv[N].idx = * value' where N < fda->nr is ok,
16  *	  but doing 'fda->priv = malloc(M)' is not allowed.
17  */
18 struct fdarray {
19 	int	       nr;
20 	int	       nr_alloc;
21 	int	       nr_autogrow;
22 	struct pollfd *entries;
23 	union {
24 		int    idx;
25 	} *priv;
26 };
27 
28 void fdarray__init(struct fdarray *fda, int nr_autogrow);
29 void fdarray__exit(struct fdarray *fda);
30 
31 struct fdarray *fdarray__new(int nr_alloc, int nr_autogrow);
32 void fdarray__delete(struct fdarray *fda);
33 
34 int fdarray__add(struct fdarray *fda, int fd, short revents);
35 int fdarray__poll(struct fdarray *fda, int timeout);
36 int fdarray__filter(struct fdarray *fda, short revents,
37 		    void (*entry_destructor)(struct fdarray *fda, int fd));
38 int fdarray__grow(struct fdarray *fda, int extra);
39 int fdarray__fprintf(struct fdarray *fda, FILE *fp);
40 
41 static inline int fdarray__available_entries(struct fdarray *fda)
42 {
43 	return fda->nr_alloc - fda->nr;
44 }
45 
46 #endif /* __API_FD_ARRAY__ */
47