internal.h

/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 * IN THE SOFTWARE.
 */

#ifndef UV_UNIX_INTERNAL_H_
#define UV_UNIX_INTERNAL_H_

#include "uv-common.h"

#include <assert.h>
#include <limits.h> /* _POSIX_PATH_MAX, PATH_MAX */
#include <stdlib.h> /* abort */
#include <string.h> /* strrchr */
#include <fcntl.h>  /* O_CLOEXEC and O_NONBLOCK, if supported. */
#include <stdio.h>
#include <errno.h>
#include <sys/socket.h>

#if defined(__STRICT_ANSI__)
# define inline __inline
#endif

#if defined(__linux__)
# include "linux-syscalls.h"
#endif /* __linux__ */

#if defined(__MVS__)
# include "os390-syscalls.h"
#endif /* __MVS__ */

#if defined(__sun)
# include <sys/port.h>
# include <port.h>
#endif /* __sun */

#if defined(_AIX)
# define reqevents events
# define rtnevents revents
# include <sys/poll.h>
#else
# include <poll.h>
#endif /* _AIX */

#if defined(__APPLE__) && !TARGET_OS_IPHONE
# include <AvailabilityMacros.h>
#endif

/*
 * Define common detection for active Thread Sanitizer
 * - clang uses __has_feature(thread_sanitizer)
 * - gcc-7+ uses __SANITIZE_THREAD__
 */
#if defined(__has_feature)
# if __has_feature(thread_sanitizer)
#  define __SANITIZE_THREAD__ 1
# endif
#endif

#if defined(PATH_MAX)
# define UV__PATH_MAX PATH_MAX
#else
# define UV__PATH_MAX 8192
#endif

#if defined(CMAKE_BOOTSTRAP)
# undef pthread_atfork
# define pthread_atfork(prepare, parent, child) \
     uv__pthread_atfork(prepare, parent, child)
int uv__pthread_atfork(void (*prepare)(void), void (*parent)(void),
                       void (*child)(void));
# undef pthread_sigmask
# define pthread_sigmask(how, set, oldset) \
     uv__pthread_sigmask(how, set, oldset)
int uv__pthread_sigmask(int how, const sigset_t* set, sigset_t* oset);
#elif defined(__ANDROID__)
int uv__pthread_sigmask(int how, const sigset_t* set, sigset_t* oset);
# ifdef pthread_sigmask
# undef pthread_sigmask
# endif
# define pthread_sigmask(how, set, oldset) uv__pthread_sigmask(how, set, oldset)
#endif

#define ACCESS_ONCE(type, var)                                                \
  (*(volatile type*) &(var))

#define ROUND_UP(a, b)                                                        \
  ((a) % (b) ? ((a) + (b)) - ((a) % (b)) : (a))

#define UNREACHABLE()                                                         \
  do {                                                                        \
    assert(0 && "unreachable code");                                          \
    abort();                                                                  \
  }                                                                           \
  while (0)

#define SAVE_ERRNO(block)                                                     \
  do {                                                                        \
    int _saved_errno = errno;                                                 \
    do { block; } while (0);                                                  \
    errno = _saved_errno;                                                     \
  }                                                                           \
  while (0)

/* The __clang__ and __INTEL_COMPILER checks are superfluous because they
 * define __GNUC__. They are here to convey to you, dear reader, that these
 * macros are enabled when compiling with clang or icc.
 */
#if defined(__clang__) ||                                                     \
    defined(__GNUC__) ||                                                      \
    defined(__INTEL_COMPILER)
# define UV_UNUSED(declaration)     __attribute__((unused)) declaration
#else
# define UV_UNUSED(declaration)     declaration
#endif

/* Leans on the fact that, on Linux, POLLRDHUP == EPOLLRDHUP. */
#ifdef POLLRDHUP
# define UV__POLLRDHUP POLLRDHUP
#else
# define UV__POLLRDHUP 0x2000
#endif

#ifdef POLLPRI
# define UV__POLLPRI POLLPRI
#else
# define UV__POLLPRI 0
#endif

#if !defined(O_CLOEXEC) && defined(__FreeBSD__)
/*
 * It may be that we are just missing `__POSIX_VISIBLE >= 200809`.
 * Try using fixed value const and give up, if it doesn't work
 */
# define O_CLOEXEC 0x00100000
#endif

typedef struct uv__stream_queued_fds_s uv__stream_queued_fds_t;

/* loop flags */
enum {
  UV_LOOP_BLOCK_SIGPROF = 0x1,
  UV_LOOP_REAP_CHILDREN = 0x2
};

/* flags of excluding ifaddr */
enum {
  UV__EXCLUDE_IFPHYS,
  UV__EXCLUDE_IFADDR
};

typedef enum {
  UV_CLOCK_PRECISE = 0,  /* Use the highest resolution clock available. */
  UV_CLOCK_FAST = 1      /* Use the fastest clock with <= 1ms granularity. */
} uv_clocktype_t;

struct uv__stream_queued_fds_s {
  unsigned int size;
  unsigned int offset;
  int fds[1];
};


#if defined(_AIX) || \
    defined(__APPLE__) || \
    defined(__DragonFly__) || \
    defined(__FreeBSD__) || \
    defined(__FreeBSD_kernel__) || \
    defined(__linux__) || \
    defined(__OpenBSD__) || \
    defined(__NetBSD__)
#define uv__nonblock uv__nonblock_ioctl
#define UV__NONBLOCK_IS_IOCTL 1
#else
#define uv__nonblock uv__nonblock_fcntl
#define UV__NONBLOCK_IS_IOCTL 0
#endif

/* On Linux, uv__nonblock_fcntl() and uv__nonblock_ioctl() do not commute
 * when O_NDELAY is not equal to O_NONBLOCK.  Case in point: linux/sparc32
 * and linux/sparc64, where O_NDELAY is O_NONBLOCK + another bit.
 *
 * Libuv uses uv__nonblock_fcntl() directly sometimes so ensure that it
 * commutes with uv__nonblock().
 */
#if defined(__linux__) && O_NDELAY != O_NONBLOCK
#undef uv__nonblock
#define uv__nonblock uv__nonblock_fcntl
#endif

/* core */
int uv__cloexec(int fd, int set);
int uv__nonblock_ioctl(int fd, int set);
int uv__nonblock_fcntl(int fd, int set);
int uv__close(int fd); /* preserves errno */
int uv__close_nocheckstdio(int fd);
int uv__close_nocancel(int fd);
int uv__socket(int domain, int type, int protocol);
ssize_t uv__recvmsg(int fd, struct msghdr *msg, int flags);
void uv__make_close_pending(uv_handle_t* handle);
int uv__getiovmax(void);

void uv__io_init(uv__io_t* w, uv__io_cb cb, int fd);
void uv__io_start(uv_loop_t* loop, uv__io_t* w, unsigned int events);
void uv__io_stop(uv_loop_t* loop, uv__io_t* w, unsigned int events);
void uv__io_close(uv_loop_t* loop, uv__io_t* w);
void uv__io_feed(uv_loop_t* loop, uv__io_t* w);
int uv__io_active(const uv__io_t* w, unsigned int events);
int uv__io_check_fd(uv_loop_t* loop, int fd);
void uv__io_poll(uv_loop_t* loop, int timeout); /* in milliseconds or -1 */
int uv__io_fork(uv_loop_t* loop);
int uv__fd_exists(uv_loop_t* loop, int fd);

/* async */
void uv__async_stop(uv_loop_t* loop);
int uv__async_fork(uv_loop_t* loop);


/* loop */
void uv__run_idle(uv_loop_t* loop);
void uv__run_check(uv_loop_t* loop);
void uv__run_prepare(uv_loop_t* loop);

/* stream */
void uv__stream_init(uv_loop_t* loop, uv_stream_t* stream,
    uv_handle_type type);
int uv__stream_open(uv_stream_t*, int fd, int flags);
void uv__stream_destroy(uv_stream_t* stream);
#if defined(__APPLE__)
int uv__stream_try_select(uv_stream_t* stream, int* fd);
#endif /* defined(__APPLE__) */
void uv__server_io(uv_loop_t* loop, uv__io_t* w, unsigned int events);
int uv__accept(int sockfd);
int uv__dup2_cloexec(int oldfd, int newfd);
int uv__open_cloexec(const char* path, int flags);
int uv__slurp(const char* filename, char* buf, size_t len);

/* tcp */
int uv__tcp_listen(uv_tcp_t* tcp, int backlog, uv_connection_cb cb);
int uv__tcp_nodelay(int fd, int on);
int uv__tcp_keepalive(int fd, int on, unsigned int delay);

/* pipe */
int uv__pipe_listen(uv_pipe_t* handle, int backlog, uv_connection_cb cb);

/* signal */
void uv__signal_close(uv_signal_t* handle);
void uv__signal_global_once_init(void);
void uv__signal_loop_cleanup(uv_loop_t* loop);
int uv__signal_loop_fork(uv_loop_t* loop);

/* platform specific */
uint64_t uv__hrtime(uv_clocktype_t type);
int uv__kqueue_init(uv_loop_t* loop);
int uv__epoll_init(uv_loop_t* loop);
int uv__platform_loop_init(uv_loop_t* loop);
void uv__platform_loop_delete(uv_loop_t* loop);
void uv__platform_invalidate_fd(uv_loop_t* loop, int fd);
int uv__process_init(uv_loop_t* loop);

/* various */
void uv__async_close(uv_async_t* handle);
void uv__check_close(uv_check_t* handle);
void uv__fs_event_close(uv_fs_event_t* handle);
void uv__idle_close(uv_idle_t* handle);
void uv__pipe_close(uv_pipe_t* handle);
void uv__poll_close(uv_poll_t* handle);
void uv__prepare_close(uv_prepare_t* handle);
void uv__process_close(uv_process_t* handle);
void uv__stream_close(uv_stream_t* handle);
void uv__tcp_close(uv_tcp_t* handle);
size_t uv__thread_stack_size(void);
void uv__udp_close(uv_udp_t* handle);
void uv__udp_finish_close(uv_udp_t* handle);
FILE* uv__open_file(const char* path);
int uv__getpwuid_r(uv_passwd_t* pwd);
int uv__search_path(const char* prog, char* buf, size_t* buflen);
void uv__wait_children(uv_loop_t* loop);

/* random */
int uv__random_devurandom(void* buf, size_t buflen);
int uv__random_getrandom(void* buf, size_t buflen);
int uv__random_getentropy(void* buf, size_t buflen);
int uv__random_readpath(const char* path, void* buf, size_t buflen);
int uv__random_sysctl(void* buf, size_t buflen);

#if defined(__APPLE__) && !defined(CMAKE_BOOTSTRAP)
int uv___stream_fd(const uv_stream_t* handle);
#define uv__stream_fd(handle) (uv___stream_fd((const uv_stream_t*) (handle)))
#else
#define uv__stream_fd(handle) ((handle)->io_watcher.fd)
#endif /* defined(__APPLE__) */

int uv__make_pipe(int fds[2], int flags);

#if defined(__APPLE__)

int uv__fsevents_init(uv_fs_event_t* handle);
int uv__fsevents_close(uv_fs_event_t* handle);
void uv__fsevents_loop_delete(uv_loop_t* loop);

#endif /* defined(__APPLE__) */

UV_UNUSED(static void uv__update_time(uv_loop_t* loop)) {
  /* Use a fast time source if available.  We only need millisecond precision.
   */
  loop->time = uv__hrtime(UV_CLOCK_FAST) / 1000000;
}

UV_UNUSED(static char* uv__basename_r(const char* path)) {
  char* s;

  s = strrchr(path, '/');
  if (s == NULL)
    return (char*) path;

  return s + 1;
}

#if defined(__linux__)
int uv__inotify_fork(uv_loop_t* loop, void* old_watchers);
#endif

typedef int (*uv__peersockfunc)(int, struct sockaddr*, socklen_t*);

int uv__getsockpeername(const uv_handle_t* handle,
                        uv__peersockfunc func,
                        struct sockaddr* name,
                        int* namelen);

#if defined(__linux__)            ||                                      \
    defined(__FreeBSD__)          ||                                      \
    defined(__FreeBSD_kernel__)   ||                                       \
    defined(__DragonFly__)
#define HAVE_MMSG 1
struct uv__mmsghdr {
  struct msghdr msg_hdr;
  unsigned int msg_len;
};

int uv__recvmmsg(int fd, struct uv__mmsghdr* mmsg, unsigned int vlen);
int uv__sendmmsg(int fd, struct uv__mmsghdr* mmsg, unsigned int vlen);
#else
#define HAVE_MMSG 0
#endif

#if defined(__sun)
#if !defined(_POSIX_VERSION) || _POSIX_VERSION < 200809L
size_t strnlen(const char* s, size_t maxlen);
#endif
#endif

#if defined(__FreeBSD__)
ssize_t
uv__fs_copy_file_range(int fd_in,
                       off_t* off_in,
                       int fd_out,
                       off_t* off_out,
                       size_t len,
                       unsigned int flags);
#endif


#endif /* UV_UNIX_INTERNAL_H_ */