WSL2-Linux-Kernel/tools/lib/api/fd/array.c

128 строки
2.4 KiB
C

/*
* Copyright (C) 2014, Red Hat Inc, Arnaldo Carvalho de Melo <acme@redhat.com>
*
* Released under the GPL v2. (and only v2, not any later version)
*/
#include "array.h"
#include <errno.h>
#include <fcntl.h>
#include <poll.h>
#include <stdlib.h>
#include <unistd.h>
void fdarray__init(struct fdarray *fda, int nr_autogrow)
{
fda->entries = NULL;
fda->priv = NULL;
fda->nr = fda->nr_alloc = 0;
fda->nr_autogrow = nr_autogrow;
}
int fdarray__grow(struct fdarray *fda, int nr)
{
void *priv;
int nr_alloc = fda->nr_alloc + nr;
size_t psize = sizeof(fda->priv[0]) * nr_alloc;
size_t size = sizeof(struct pollfd) * nr_alloc;
struct pollfd *entries = realloc(fda->entries, size);
if (entries == NULL)
return -ENOMEM;
priv = realloc(fda->priv, psize);
if (priv == NULL) {
free(entries);
return -ENOMEM;
}
fda->nr_alloc = nr_alloc;
fda->entries = entries;
fda->priv = priv;
return 0;
}
struct fdarray *fdarray__new(int nr_alloc, int nr_autogrow)
{
struct fdarray *fda = calloc(1, sizeof(*fda));
if (fda != NULL) {
if (fdarray__grow(fda, nr_alloc)) {
free(fda);
fda = NULL;
} else {
fda->nr_autogrow = nr_autogrow;
}
}
return fda;
}
void fdarray__exit(struct fdarray *fda)
{
free(fda->entries);
free(fda->priv);
fdarray__init(fda, 0);
}
void fdarray__delete(struct fdarray *fda)
{
fdarray__exit(fda);
free(fda);
}
int fdarray__add(struct fdarray *fda, int fd, short revents)
{
int pos = fda->nr;
if (fda->nr == fda->nr_alloc &&
fdarray__grow(fda, fda->nr_autogrow) < 0)
return -ENOMEM;
fda->entries[fda->nr].fd = fd;
fda->entries[fda->nr].events = revents;
fda->nr++;
return pos;
}
int fdarray__filter(struct fdarray *fda, short revents,
void (*entry_destructor)(struct fdarray *fda, int fd))
{
int fd, nr = 0;
if (fda->nr == 0)
return 0;
for (fd = 0; fd < fda->nr; ++fd) {
if (fda->entries[fd].revents & revents) {
if (entry_destructor)
entry_destructor(fda, fd);
continue;
}
if (fd != nr) {
fda->entries[nr] = fda->entries[fd];
fda->priv[nr] = fda->priv[fd];
}
++nr;
}
return fda->nr = nr;
}
int fdarray__poll(struct fdarray *fda, int timeout)
{
return poll(fda->entries, fda->nr, timeout);
}
int fdarray__fprintf(struct fdarray *fda, FILE *fp)
{
int fd, printed = fprintf(fp, "%d [ ", fda->nr);
for (fd = 0; fd < fda->nr; ++fd)
printed += fprintf(fp, "%s%d", fd ? ", " : "", fda->entries[fd].fd);
return printed + fprintf(fp, " ]");
}