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Diffstat (limited to 'include/ruby/internal/intern/select/posix.h')
| -rw-r--r-- | include/ruby/internal/intern/select/posix.h | 144 |
1 files changed, 144 insertions, 0 deletions
diff --git a/include/ruby/internal/intern/select/posix.h b/include/ruby/internal/intern/select/posix.h new file mode 100644 index 0000000000..0a9b0b2e51 --- /dev/null +++ b/include/ruby/internal/intern/select/posix.h @@ -0,0 +1,144 @@ +#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 sibling implementations. */ +#define rb_fd_init_copy(d, s) (*(d) = *(s)) +#define rb_fd_term(f) ((void)(f)) +/** @endcond */ + +#endif /* RBIMPL_INTERN_SELECT_POSIX_H */ |