Current File : //opt/alt/ruby31/include/ruby/internal/intern/select/posix.h
#ifndef RBIMPL_INTERN_SELECT_POSIX_H /*-*-C++-*-vi:se ft=cpp:*/
#define RBIMPL_INTERN_SELECT_POSIX_H
/**
* @file
* @author Ruby developers <ruby-core@ruby-lang.org>
* @copyright This file is a part of the programming language Ruby.
* Permission is hereby granted, to either redistribute and/or
* modify this file, provided that the conditions mentioned in the
* file COPYING are met. Consult the file for details.
* @warning Symbols prefixed with either `RBIMPL` or `rbimpl` are
* implementation details. Don't take them as canon. They could
* rapidly appear then vanish. The name (path) of this header file
* is also an implementation detail. Do not expect it to persist
* at the place it is now. Developers are free to move it anywhere
* anytime at will.
* @note To ruby-core: remember that this header can be possibly
* recursively included from extension libraries written in C++.
* Do not expect for instance `__VA_ARGS__` is always available.
* We assume C99 for ruby itself but we don't assume languages of
* extension libraries. They could be written in C++98.
* @brief Public APIs to provide ::rb_fd_select().
*/
#include "ruby/internal/config.h"
#ifdef HAVE_SYS_SELECT_H
# include <sys/select.h> /* for select(2) (modern POSIX) */
#endif
#ifdef HAVE_UNISTD_H
# include <unistd.h> /* for select(2) (archaic UNIX) */
#endif
#include "ruby/internal/attr/const.h"
#include "ruby/internal/attr/noalias.h"
#include "ruby/internal/attr/nonnull.h"
#include "ruby/internal/attr/pure.h"
/**
* The data structure which wraps the fd_set bitmap used by `select(2)`. This
* allows Ruby to use FD sets larger than what has been historically allowed on
* modern platforms.
*
* @internal
*
* ... but because this header file is included only when the system is with
* that "historic restrictions", this is nothing more than an alias of fd_set.
*/
typedef fd_set rb_fdset_t;
/** Clears the given ::rb_fdset_t. */
#define rb_fd_zero FD_ZERO
/** Sets the given fd to the ::rb_fdset_t. */
#define rb_fd_set FD_SET
/** Unsets the given fd from the ::rb_fdset_t. */
#define rb_fd_clr FD_CLR
/** Queries if the given fd is in the ::rb_fdset_t. */
#define rb_fd_isset FD_ISSET
/** Initialises the :given :rb_fdset_t. */
#define rb_fd_init FD_ZERO
/** Waits for multiple file descriptors at once. */
#define rb_fd_select select
/**@cond INTERNAL_MACRO */
#define rb_fd_copy rb_fd_copy
#define rb_fd_dup rb_fd_dup
#define rb_fd_ptr rb_fd_ptr
#define rb_fd_max rb_fd_max
/** @endcond */
RBIMPL_ATTR_NONNULL(())
RBIMPL_ATTR_NOALIAS()
/**
* Destructively overwrites an fdset with another.
*
* @param[out] dst Target fdset.
* @param[in] src Source fdset.
* @param[in] n Unused parameter.
* @post `dst` is a copy of `src`.
*/
static inline void
rb_fd_copy(rb_fdset_t *dst, const fd_set *src, int n)
{
*dst = *src;
}
RBIMPL_ATTR_NONNULL(())
RBIMPL_ATTR_NOALIAS()
/**
* Destructively overwrites an fdset with another.
*
* @param[out] dst Target fdset.
* @param[in] src Source fdset.
* @post `dst` is a copy of `src`.
*/
static inline void
rb_fd_dup(rb_fdset_t *dst, const fd_set *src)
{
*dst = *src;
}
RBIMPL_ATTR_PURE()
/* :TODO: can this function be __attribute__((returns_nonnull)) or not? */
/**
* Raw pointer to `fd_set`.
*
* @param[in] f Target fdset.
* @return Underlying fd_set.
*
* @internal
*
* Extension library must not touch raw pointers. It was a bad idea to let
* them use it.
*/
static inline fd_set *
rb_fd_ptr(rb_fdset_t *f)
{
return f;
}
RBIMPL_ATTR_CONST()
/**
* It seems this function has no use. Maybe just remove?
*
* @param[in] f A set.
* @return Number of file descriptors stored.
*/
static inline int
rb_fd_max(const rb_fdset_t *f)
{
return FD_SETSIZE;
}
/** @cond INTERNAL_MACRO */
/* :FIXME: What are these? They don't exist for shibling implementations. */
#define rb_fd_init_copy(d, s) (*(d) = *(s))
#define rb_fd_term(f) ((void)(f))
/** @endcond */
#endif /* RBIMPL_INTERN_SELECT_POSIX_H */