xref: /libuv/include/uv.h (revision e8969bff)
1 /* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
2  *
3  * Permission is hereby granted, free of charge, to any person obtaining a copy
4  * of this software and associated documentation files (the "Software"), to
5  * deal in the Software without restriction, including without limitation the
6  * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
7  * sell copies of the Software, and to permit persons to whom the Software is
8  * furnished to do so, subject to the following conditions:
9  *
10  * The above copyright notice and this permission notice shall be included in
11  * all copies or substantial portions of the Software.
12  *
13  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
14  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
15  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
16  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
17  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
18  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
19  * IN THE SOFTWARE.
20  */
21 
22 /* See https://github.com/libuv/libuv#documentation for documentation. */
23 
24 #ifndef UV_H
25 #define UV_H
26 #ifdef __cplusplus
27 extern "C" {
28 #endif
29 
30 #if defined(BUILDING_UV_SHARED) && defined(USING_UV_SHARED)
31 #error "Define either BUILDING_UV_SHARED or USING_UV_SHARED, not both."
32 #endif
33 
34 #ifndef UV_EXTERN
35 #ifdef _WIN32
36   /* Windows - set up dll import/export decorators. */
37 # if defined(BUILDING_UV_SHARED)
38     /* Building shared library. */
39 #   define UV_EXTERN __declspec(dllexport)
40 # elif defined(USING_UV_SHARED)
41     /* Using shared library. */
42 #   define UV_EXTERN __declspec(dllimport)
43 # else
44     /* Building static library. */
45 #   define UV_EXTERN /* nothing */
46 # endif
47 #elif __GNUC__ >= 4
48 # define UV_EXTERN __attribute__((visibility("default")))
49 #elif defined(__SUNPRO_C) && (__SUNPRO_C >= 0x550) /* Sun Studio >= 8 */
50 # define UV_EXTERN __global
51 #else
52 # define UV_EXTERN /* nothing */
53 #endif
54 #endif /* UV_EXTERN */
55 
56 #include "uv/errno.h"
57 #include "uv/version.h"
58 #include <stddef.h>
59 #include <stdio.h>
60 #include <stdint.h>
61 
62 /* Internal type, do not use. */
63 struct uv__queue {
64   struct uv__queue* next;
65   struct uv__queue* prev;
66 };
67 
68 #if defined(_WIN32)
69 # include "uv/win.h"
70 #else
71 # include "uv/unix.h"
72 #endif
73 
74 /* Expand this list if necessary. */
75 #define UV_ERRNO_MAP(XX)                                                      \
76   XX(E2BIG, "argument list too long")                                         \
77   XX(EACCES, "permission denied")                                             \
78   XX(EADDRINUSE, "address already in use")                                    \
79   XX(EADDRNOTAVAIL, "address not available")                                  \
80   XX(EAFNOSUPPORT, "address family not supported")                            \
81   XX(EAGAIN, "resource temporarily unavailable")                              \
82   XX(EAI_ADDRFAMILY, "address family not supported")                          \
83   XX(EAI_AGAIN, "temporary failure")                                          \
84   XX(EAI_BADFLAGS, "bad ai_flags value")                                      \
85   XX(EAI_BADHINTS, "invalid value for hints")                                 \
86   XX(EAI_CANCELED, "request canceled")                                        \
87   XX(EAI_FAIL, "permanent failure")                                           \
88   XX(EAI_FAMILY, "ai_family not supported")                                   \
89   XX(EAI_MEMORY, "out of memory")                                             \
90   XX(EAI_NODATA, "no address")                                                \
91   XX(EAI_NONAME, "unknown node or service")                                   \
92   XX(EAI_OVERFLOW, "argument buffer overflow")                                \
93   XX(EAI_PROTOCOL, "resolved protocol is unknown")                            \
94   XX(EAI_SERVICE, "service not available for socket type")                    \
95   XX(EAI_SOCKTYPE, "socket type not supported")                               \
96   XX(EALREADY, "connection already in progress")                              \
97   XX(EBADF, "bad file descriptor")                                            \
98   XX(EBUSY, "resource busy or locked")                                        \
99   XX(ECANCELED, "operation canceled")                                         \
100   XX(ECHARSET, "invalid Unicode character")                                   \
101   XX(ECONNABORTED, "software caused connection abort")                        \
102   XX(ECONNREFUSED, "connection refused")                                      \
103   XX(ECONNRESET, "connection reset by peer")                                  \
104   XX(EDESTADDRREQ, "destination address required")                            \
105   XX(EEXIST, "file already exists")                                           \
106   XX(EFAULT, "bad address in system call argument")                           \
107   XX(EFBIG, "file too large")                                                 \
108   XX(EHOSTUNREACH, "host is unreachable")                                     \
109   XX(EINTR, "interrupted system call")                                        \
110   XX(EINVAL, "invalid argument")                                              \
111   XX(EIO, "i/o error")                                                        \
112   XX(EISCONN, "socket is already connected")                                  \
113   XX(EISDIR, "illegal operation on a directory")                              \
114   XX(ELOOP, "too many symbolic links encountered")                            \
115   XX(EMFILE, "too many open files")                                           \
116   XX(EMSGSIZE, "message too long")                                            \
117   XX(ENAMETOOLONG, "name too long")                                           \
118   XX(ENETDOWN, "network is down")                                             \
119   XX(ENETUNREACH, "network is unreachable")                                   \
120   XX(ENFILE, "file table overflow")                                           \
121   XX(ENOBUFS, "no buffer space available")                                    \
122   XX(ENODEV, "no such device")                                                \
123   XX(ENOENT, "no such file or directory")                                     \
124   XX(ENOMEM, "not enough memory")                                             \
125   XX(ENONET, "machine is not on the network")                                 \
126   XX(ENOPROTOOPT, "protocol not available")                                   \
127   XX(ENOSPC, "no space left on device")                                       \
128   XX(ENOSYS, "function not implemented")                                      \
129   XX(ENOTCONN, "socket is not connected")                                     \
130   XX(ENOTDIR, "not a directory")                                              \
131   XX(ENOTEMPTY, "directory not empty")                                        \
132   XX(ENOTSOCK, "socket operation on non-socket")                              \
133   XX(ENOTSUP, "operation not supported on socket")                            \
134   XX(EOVERFLOW, "value too large for defined data type")                      \
135   XX(EPERM, "operation not permitted")                                        \
136   XX(EPIPE, "broken pipe")                                                    \
137   XX(EPROTO, "protocol error")                                                \
138   XX(EPROTONOSUPPORT, "protocol not supported")                               \
139   XX(EPROTOTYPE, "protocol wrong type for socket")                            \
140   XX(ERANGE, "result too large")                                              \
141   XX(EROFS, "read-only file system")                                          \
142   XX(ESHUTDOWN, "cannot send after transport endpoint shutdown")              \
143   XX(ESPIPE, "invalid seek")                                                  \
144   XX(ESRCH, "no such process")                                                \
145   XX(ETIMEDOUT, "connection timed out")                                       \
146   XX(ETXTBSY, "text file is busy")                                            \
147   XX(EXDEV, "cross-device link not permitted")                                \
148   XX(UNKNOWN, "unknown error")                                                \
149   XX(EOF, "end of file")                                                      \
150   XX(ENXIO, "no such device or address")                                      \
151   XX(EMLINK, "too many links")                                                \
152   XX(EHOSTDOWN, "host is down")                                               \
153   XX(EREMOTEIO, "remote I/O error")                                           \
154   XX(ENOTTY, "inappropriate ioctl for device")                                \
155   XX(EFTYPE, "inappropriate file type or format")                             \
156   XX(EILSEQ, "illegal byte sequence")                                         \
157   XX(ESOCKTNOSUPPORT, "socket type not supported")                            \
158   XX(ENODATA, "no data available")                                            \
159   XX(EUNATCH, "protocol driver not attached")                                 \
160   XX(ENOEXEC, "exec format error")                                            \
161 
162 #define UV_HANDLE_TYPE_MAP(XX)                                                \
163   XX(ASYNC, async)                                                            \
164   XX(CHECK, check)                                                            \
165   XX(FS_EVENT, fs_event)                                                      \
166   XX(FS_POLL, fs_poll)                                                        \
167   XX(HANDLE, handle)                                                          \
168   XX(IDLE, idle)                                                              \
169   XX(NAMED_PIPE, pipe)                                                        \
170   XX(POLL, poll)                                                              \
171   XX(PREPARE, prepare)                                                        \
172   XX(PROCESS, process)                                                        \
173   XX(STREAM, stream)                                                          \
174   XX(TCP, tcp)                                                                \
175   XX(TIMER, timer)                                                            \
176   XX(TTY, tty)                                                                \
177   XX(UDP, udp)                                                                \
178   XX(SIGNAL, signal)                                                          \
179 
180 #define UV_REQ_TYPE_MAP(XX)                                                   \
181   XX(REQ, req)                                                                \
182   XX(CONNECT, connect)                                                        \
183   XX(WRITE, write)                                                            \
184   XX(SHUTDOWN, shutdown)                                                      \
185   XX(UDP_SEND, udp_send)                                                      \
186   XX(FS, fs)                                                                  \
187   XX(WORK, work)                                                              \
188   XX(GETADDRINFO, getaddrinfo)                                                \
189   XX(GETNAMEINFO, getnameinfo)                                                \
190   XX(RANDOM, random)                                                          \
191 
192 typedef enum {
193 #define XX(code, _) UV_ ## code = UV__ ## code,
194   UV_ERRNO_MAP(XX)
195 #undef XX
196   UV_ERRNO_MAX = UV__EOF - 1
197 } uv_errno_t;
198 
199 typedef enum {
200   UV_UNKNOWN_HANDLE = 0,
201 #define XX(uc, lc) UV_##uc,
202   UV_HANDLE_TYPE_MAP(XX)
203 #undef XX
204   UV_FILE,
205   UV_HANDLE_TYPE_MAX
206 } uv_handle_type;
207 
208 typedef enum {
209   UV_UNKNOWN_REQ = 0,
210 #define XX(uc, lc) UV_##uc,
211   UV_REQ_TYPE_MAP(XX)
212 #undef XX
213   UV_REQ_TYPE_PRIVATE
214   UV_REQ_TYPE_MAX
215 } uv_req_type;
216 
217 
218 /* Handle types. */
219 typedef struct uv_loop_s uv_loop_t;
220 typedef struct uv_handle_s uv_handle_t;
221 typedef struct uv_dir_s uv_dir_t;
222 typedef struct uv_stream_s uv_stream_t;
223 typedef struct uv_tcp_s uv_tcp_t;
224 typedef struct uv_udp_s uv_udp_t;
225 typedef struct uv_pipe_s uv_pipe_t;
226 typedef struct uv_tty_s uv_tty_t;
227 typedef struct uv_poll_s uv_poll_t;
228 typedef struct uv_timer_s uv_timer_t;
229 typedef struct uv_prepare_s uv_prepare_t;
230 typedef struct uv_check_s uv_check_t;
231 typedef struct uv_idle_s uv_idle_t;
232 typedef struct uv_async_s uv_async_t;
233 typedef struct uv_process_s uv_process_t;
234 typedef struct uv_fs_event_s uv_fs_event_t;
235 typedef struct uv_fs_poll_s uv_fs_poll_t;
236 typedef struct uv_signal_s uv_signal_t;
237 
238 /* Request types. */
239 typedef struct uv_req_s uv_req_t;
240 typedef struct uv_getaddrinfo_s uv_getaddrinfo_t;
241 typedef struct uv_getnameinfo_s uv_getnameinfo_t;
242 typedef struct uv_shutdown_s uv_shutdown_t;
243 typedef struct uv_write_s uv_write_t;
244 typedef struct uv_connect_s uv_connect_t;
245 typedef struct uv_udp_send_s uv_udp_send_t;
246 typedef struct uv_fs_s uv_fs_t;
247 typedef struct uv_work_s uv_work_t;
248 typedef struct uv_random_s uv_random_t;
249 
250 /* None of the above. */
251 typedef struct uv_env_item_s uv_env_item_t;
252 typedef struct uv_cpu_info_s uv_cpu_info_t;
253 typedef struct uv_interface_address_s uv_interface_address_t;
254 typedef struct uv_dirent_s uv_dirent_t;
255 typedef struct uv_passwd_s uv_passwd_t;
256 typedef struct uv_group_s uv_group_t;
257 typedef struct uv_utsname_s uv_utsname_t;
258 typedef struct uv_statfs_s uv_statfs_t;
259 
260 typedef struct uv_metrics_s uv_metrics_t;
261 
262 typedef enum {
263   UV_LOOP_BLOCK_SIGNAL = 0,
264   UV_METRICS_IDLE_TIME,
265   UV_LOOP_USE_IO_URING_SQPOLL
266 #define UV_LOOP_USE_IO_URING_SQPOLL UV_LOOP_USE_IO_URING_SQPOLL
267 } uv_loop_option;
268 
269 typedef enum {
270   UV_RUN_DEFAULT = 0,
271   UV_RUN_ONCE,
272   UV_RUN_NOWAIT
273 } uv_run_mode;
274 
275 
276 UV_EXTERN unsigned int uv_version(void);
277 UV_EXTERN const char* uv_version_string(void);
278 
279 typedef void* (*uv_malloc_func)(size_t size);
280 typedef void* (*uv_realloc_func)(void* ptr, size_t size);
281 typedef void* (*uv_calloc_func)(size_t count, size_t size);
282 typedef void (*uv_free_func)(void* ptr);
283 
284 UV_EXTERN void uv_library_shutdown(void);
285 
286 UV_EXTERN int uv_replace_allocator(uv_malloc_func malloc_func,
287                                    uv_realloc_func realloc_func,
288                                    uv_calloc_func calloc_func,
289                                    uv_free_func free_func);
290 
291 UV_EXTERN uv_loop_t* uv_default_loop(void);
292 UV_EXTERN int uv_loop_init(uv_loop_t* loop);
293 UV_EXTERN int uv_loop_close(uv_loop_t* loop);
294 /*
295  * NOTE:
296  *  This function is DEPRECATED, users should
297  *  allocate the loop manually and use uv_loop_init instead.
298  */
299 UV_EXTERN uv_loop_t* uv_loop_new(void);
300 /*
301  * NOTE:
302  *  This function is DEPRECATED. Users should use
303  *  uv_loop_close and free the memory manually instead.
304  */
305 UV_EXTERN void uv_loop_delete(uv_loop_t*);
306 UV_EXTERN size_t uv_loop_size(void);
307 UV_EXTERN int uv_loop_alive(const uv_loop_t* loop);
308 UV_EXTERN int uv_loop_configure(uv_loop_t* loop, uv_loop_option option, ...);
309 UV_EXTERN int uv_loop_fork(uv_loop_t* loop);
310 
311 UV_EXTERN int uv_run(uv_loop_t*, uv_run_mode mode);
312 UV_EXTERN void uv_stop(uv_loop_t*);
313 
314 UV_EXTERN void uv_ref(uv_handle_t*);
315 UV_EXTERN void uv_unref(uv_handle_t*);
316 UV_EXTERN int uv_has_ref(const uv_handle_t*);
317 
318 UV_EXTERN void uv_update_time(uv_loop_t*);
319 UV_EXTERN uint64_t uv_now(const uv_loop_t*);
320 
321 UV_EXTERN int uv_backend_fd(const uv_loop_t*);
322 UV_EXTERN int uv_backend_timeout(const uv_loop_t*);
323 
324 typedef void (*uv_alloc_cb)(uv_handle_t* handle,
325                             size_t suggested_size,
326                             uv_buf_t* buf);
327 typedef void (*uv_read_cb)(uv_stream_t* stream,
328                            ssize_t nread,
329                            const uv_buf_t* buf);
330 typedef void (*uv_write_cb)(uv_write_t* req, int status);
331 typedef void (*uv_connect_cb)(uv_connect_t* req, int status);
332 typedef void (*uv_shutdown_cb)(uv_shutdown_t* req, int status);
333 typedef void (*uv_connection_cb)(uv_stream_t* server, int status);
334 typedef void (*uv_close_cb)(uv_handle_t* handle);
335 typedef void (*uv_poll_cb)(uv_poll_t* handle, int status, int events);
336 typedef void (*uv_timer_cb)(uv_timer_t* handle);
337 typedef void (*uv_async_cb)(uv_async_t* handle);
338 typedef void (*uv_prepare_cb)(uv_prepare_t* handle);
339 typedef void (*uv_check_cb)(uv_check_t* handle);
340 typedef void (*uv_idle_cb)(uv_idle_t* handle);
341 typedef void (*uv_exit_cb)(uv_process_t*, int64_t exit_status, int term_signal);
342 typedef void (*uv_walk_cb)(uv_handle_t* handle, void* arg);
343 typedef void (*uv_fs_cb)(uv_fs_t* req);
344 typedef void (*uv_work_cb)(uv_work_t* req);
345 typedef void (*uv_after_work_cb)(uv_work_t* req, int status);
346 typedef void (*uv_getaddrinfo_cb)(uv_getaddrinfo_t* req,
347                                   int status,
348                                   struct addrinfo* res);
349 typedef void (*uv_getnameinfo_cb)(uv_getnameinfo_t* req,
350                                   int status,
351                                   const char* hostname,
352                                   const char* service);
353 typedef void (*uv_random_cb)(uv_random_t* req,
354                              int status,
355                              void* buf,
356                              size_t buflen);
357 
358 typedef enum {
359   UV_CLOCK_MONOTONIC,
360   UV_CLOCK_REALTIME
361 } uv_clock_id;
362 
363 /* XXX(bnoordhuis) not 2038-proof, https://github.com/libuv/libuv/issues/3864 */
364 typedef struct {
365   long tv_sec;
366   long tv_nsec;
367 } uv_timespec_t;
368 
369 typedef struct {
370   int64_t tv_sec;
371   int32_t tv_nsec;
372 } uv_timespec64_t;
373 
374 /* XXX(bnoordhuis) not 2038-proof, https://github.com/libuv/libuv/issues/3864 */
375 typedef struct {
376   long tv_sec;
377   long tv_usec;
378 } uv_timeval_t;
379 
380 typedef struct {
381   int64_t tv_sec;
382   int32_t tv_usec;
383 } uv_timeval64_t;
384 
385 typedef struct {
386   uint64_t st_dev;
387   uint64_t st_mode;
388   uint64_t st_nlink;
389   uint64_t st_uid;
390   uint64_t st_gid;
391   uint64_t st_rdev;
392   uint64_t st_ino;
393   uint64_t st_size;
394   uint64_t st_blksize;
395   uint64_t st_blocks;
396   uint64_t st_flags;
397   uint64_t st_gen;
398   uv_timespec_t st_atim;
399   uv_timespec_t st_mtim;
400   uv_timespec_t st_ctim;
401   uv_timespec_t st_birthtim;
402 } uv_stat_t;
403 
404 
405 typedef void (*uv_fs_event_cb)(uv_fs_event_t* handle,
406                                const char* filename,
407                                int events,
408                                int status);
409 
410 typedef void (*uv_fs_poll_cb)(uv_fs_poll_t* handle,
411                               int status,
412                               const uv_stat_t* prev,
413                               const uv_stat_t* curr);
414 
415 typedef void (*uv_signal_cb)(uv_signal_t* handle, int signum);
416 
417 
418 typedef enum {
419   UV_LEAVE_GROUP = 0,
420   UV_JOIN_GROUP
421 } uv_membership;
422 
423 
424 UV_EXTERN int uv_translate_sys_error(int sys_errno);
425 
426 UV_EXTERN const char* uv_strerror(int err);
427 UV_EXTERN char* uv_strerror_r(int err, char* buf, size_t buflen);
428 
429 UV_EXTERN const char* uv_err_name(int err);
430 UV_EXTERN char* uv_err_name_r(int err, char* buf, size_t buflen);
431 
432 
433 #define UV_REQ_FIELDS                                                         \
434   /* public */                                                                \
435   void* data;                                                                 \
436   /* read-only */                                                             \
437   uv_req_type type;                                                           \
438   /* private */                                                               \
439   void* reserved[6];                                                          \
440   UV_REQ_PRIVATE_FIELDS                                                       \
441 
442 /* Abstract base class of all requests. */
443 struct uv_req_s {
444   UV_REQ_FIELDS
445 };
446 
447 
448 /* Platform-specific request types. */
449 UV_PRIVATE_REQ_TYPES
450 
451 
452 UV_EXTERN int uv_shutdown(uv_shutdown_t* req,
453                           uv_stream_t* handle,
454                           uv_shutdown_cb cb);
455 
456 struct uv_shutdown_s {
457   UV_REQ_FIELDS
458   uv_stream_t* handle;
459   uv_shutdown_cb cb;
460   UV_SHUTDOWN_PRIVATE_FIELDS
461 };
462 
463 
464 #define UV_HANDLE_FIELDS                                                      \
465   /* public */                                                                \
466   void* data;                                                                 \
467   /* read-only */                                                             \
468   uv_loop_t* loop;                                                            \
469   uv_handle_type type;                                                        \
470   /* private */                                                               \
471   uv_close_cb close_cb;                                                       \
472   struct uv__queue handle_queue;                                              \
473   union {                                                                     \
474     int fd;                                                                   \
475     void* reserved[4];                                                        \
476   } u;                                                                        \
477   UV_HANDLE_PRIVATE_FIELDS                                                    \
478 
479 /* The abstract base class of all handles. */
480 struct uv_handle_s {
481   UV_HANDLE_FIELDS
482 };
483 
484 UV_EXTERN size_t uv_handle_size(uv_handle_type type);
485 UV_EXTERN uv_handle_type uv_handle_get_type(const uv_handle_t* handle);
486 UV_EXTERN const char* uv_handle_type_name(uv_handle_type type);
487 UV_EXTERN void* uv_handle_get_data(const uv_handle_t* handle);
488 UV_EXTERN uv_loop_t* uv_handle_get_loop(const uv_handle_t* handle);
489 UV_EXTERN void uv_handle_set_data(uv_handle_t* handle, void* data);
490 
491 UV_EXTERN size_t uv_req_size(uv_req_type type);
492 UV_EXTERN void* uv_req_get_data(const uv_req_t* req);
493 UV_EXTERN void uv_req_set_data(uv_req_t* req, void* data);
494 UV_EXTERN uv_req_type uv_req_get_type(const uv_req_t* req);
495 UV_EXTERN const char* uv_req_type_name(uv_req_type type);
496 
497 UV_EXTERN int uv_is_active(const uv_handle_t* handle);
498 
499 UV_EXTERN void uv_walk(uv_loop_t* loop, uv_walk_cb walk_cb, void* arg);
500 
501 /* Helpers for ad hoc debugging, no API/ABI stability guaranteed. */
502 UV_EXTERN void uv_print_all_handles(uv_loop_t* loop, FILE* stream);
503 UV_EXTERN void uv_print_active_handles(uv_loop_t* loop, FILE* stream);
504 
505 UV_EXTERN void uv_close(uv_handle_t* handle, uv_close_cb close_cb);
506 
507 UV_EXTERN int uv_send_buffer_size(uv_handle_t* handle, int* value);
508 UV_EXTERN int uv_recv_buffer_size(uv_handle_t* handle, int* value);
509 
510 UV_EXTERN int uv_fileno(const uv_handle_t* handle, uv_os_fd_t* fd);
511 
512 UV_EXTERN uv_buf_t uv_buf_init(char* base, unsigned int len);
513 
514 UV_EXTERN int uv_pipe(uv_file fds[2], int read_flags, int write_flags);
515 UV_EXTERN int uv_socketpair(int type,
516                             int protocol,
517                             uv_os_sock_t socket_vector[2],
518                             int flags0,
519                             int flags1);
520 
521 #define UV_STREAM_FIELDS                                                      \
522   /* number of bytes queued for writing */                                    \
523   size_t write_queue_size;                                                    \
524   uv_alloc_cb alloc_cb;                                                       \
525   uv_read_cb read_cb;                                                         \
526   /* private */                                                               \
527   UV_STREAM_PRIVATE_FIELDS
528 
529 /*
530  * uv_stream_t is a subclass of uv_handle_t.
531  *
532  * uv_stream is an abstract class.
533  *
534  * uv_stream_t is the parent class of uv_tcp_t, uv_pipe_t and uv_tty_t.
535  */
536 struct uv_stream_s {
537   UV_HANDLE_FIELDS
538   UV_STREAM_FIELDS
539 };
540 
541 UV_EXTERN size_t uv_stream_get_write_queue_size(const uv_stream_t* stream);
542 
543 UV_EXTERN int uv_listen(uv_stream_t* stream, int backlog, uv_connection_cb cb);
544 UV_EXTERN int uv_accept(uv_stream_t* server, uv_stream_t* client);
545 
546 UV_EXTERN int uv_read_start(uv_stream_t*,
547                             uv_alloc_cb alloc_cb,
548                             uv_read_cb read_cb);
549 UV_EXTERN int uv_read_stop(uv_stream_t*);
550 
551 UV_EXTERN int uv_write(uv_write_t* req,
552                        uv_stream_t* handle,
553                        const uv_buf_t bufs[],
554                        unsigned int nbufs,
555                        uv_write_cb cb);
556 UV_EXTERN int uv_write2(uv_write_t* req,
557                         uv_stream_t* handle,
558                         const uv_buf_t bufs[],
559                         unsigned int nbufs,
560                         uv_stream_t* send_handle,
561                         uv_write_cb cb);
562 UV_EXTERN int uv_try_write(uv_stream_t* handle,
563                            const uv_buf_t bufs[],
564                            unsigned int nbufs);
565 UV_EXTERN int uv_try_write2(uv_stream_t* handle,
566                             const uv_buf_t bufs[],
567                             unsigned int nbufs,
568                             uv_stream_t* send_handle);
569 
570 /* uv_write_t is a subclass of uv_req_t. */
571 struct uv_write_s {
572   UV_REQ_FIELDS
573   uv_write_cb cb;
574   uv_stream_t* send_handle; /* TODO: make private and unix-only in v2.x. */
575   uv_stream_t* handle;
576   UV_WRITE_PRIVATE_FIELDS
577 };
578 
579 
580 UV_EXTERN int uv_is_readable(const uv_stream_t* handle);
581 UV_EXTERN int uv_is_writable(const uv_stream_t* handle);
582 
583 UV_EXTERN int uv_stream_set_blocking(uv_stream_t* handle, int blocking);
584 
585 UV_EXTERN int uv_is_closing(const uv_handle_t* handle);
586 
587 
588 /*
589  * uv_tcp_t is a subclass of uv_stream_t.
590  *
591  * Represents a TCP stream or TCP server.
592  */
593 struct uv_tcp_s {
594   UV_HANDLE_FIELDS
595   UV_STREAM_FIELDS
596   UV_TCP_PRIVATE_FIELDS
597 };
598 
599 UV_EXTERN int uv_tcp_init(uv_loop_t*, uv_tcp_t* handle);
600 UV_EXTERN int uv_tcp_init_ex(uv_loop_t*, uv_tcp_t* handle, unsigned int flags);
601 UV_EXTERN int uv_tcp_open(uv_tcp_t* handle, uv_os_sock_t sock);
602 UV_EXTERN int uv_tcp_nodelay(uv_tcp_t* handle, int enable);
603 UV_EXTERN int uv_tcp_keepalive(uv_tcp_t* handle,
604                                int enable,
605                                unsigned int delay);
606 UV_EXTERN int uv_tcp_simultaneous_accepts(uv_tcp_t* handle, int enable);
607 
608 enum uv_tcp_flags {
609   /* Used with uv_tcp_bind, when an IPv6 address is used. */
610   UV_TCP_IPV6ONLY = 1,
611 
612   /* Enable SO_REUSEPORT socket option when binding the handle.
613    * This allows completely duplicate bindings by multiple processes
614    * or threads if they all set SO_REUSEPORT before binding the port.
615    * Incoming connections are distributed across the participating
616    * listener sockets.
617    *
618    * This flag is available only on Linux 3.9+, DragonFlyBSD 3.6+,
619    * FreeBSD 12.0+, Solaris 11.4, and AIX 7.2.5+ for now.
620    */
621   UV_TCP_REUSEPORT = 2,
622 };
623 
624 UV_EXTERN int uv_tcp_bind(uv_tcp_t* handle,
625                           const struct sockaddr* addr,
626                           unsigned int flags);
627 UV_EXTERN int uv_tcp_getsockname(const uv_tcp_t* handle,
628                                  struct sockaddr* name,
629                                  int* namelen);
630 UV_EXTERN int uv_tcp_getpeername(const uv_tcp_t* handle,
631                                  struct sockaddr* name,
632                                  int* namelen);
633 UV_EXTERN int uv_tcp_close_reset(uv_tcp_t* handle, uv_close_cb close_cb);
634 UV_EXTERN int uv_tcp_connect(uv_connect_t* req,
635                              uv_tcp_t* handle,
636                              const struct sockaddr* addr,
637                              uv_connect_cb cb);
638 
639 /* uv_connect_t is a subclass of uv_req_t. */
640 struct uv_connect_s {
641   UV_REQ_FIELDS
642   uv_connect_cb cb;
643   uv_stream_t* handle;
644   UV_CONNECT_PRIVATE_FIELDS
645 };
646 
647 
648 /*
649  * UDP support.
650  */
651 
652 enum uv_udp_flags {
653   /* Disables dual stack mode. */
654   UV_UDP_IPV6ONLY = 1,
655   /*
656    * Indicates message was truncated because read buffer was too small. The
657    * remainder was discarded by the OS. Used in uv_udp_recv_cb.
658    */
659   UV_UDP_PARTIAL = 2,
660   /*
661    * Indicates if SO_REUSEADDR will be set when binding the handle.
662    * This sets the SO_REUSEPORT socket flag on the BSDs (except for
663    * DragonFlyBSD), OS X, and other platforms where SO_REUSEPORTs don't
664    * have the capability of load balancing, as the opposite of what
665    * UV_UDP_REUSEPORT would do. On other Unix platforms, it sets the
666    * SO_REUSEADDR flag. What that means is that multiple threads or
667    * processes can bind to the same address without error (provided
668    * they all set the flag) but only the last one to bind will receive
669    * any traffic, in effect "stealing" the port from the previous listener.
670    */
671   UV_UDP_REUSEADDR = 4,
672   /*
673    * Indicates that the message was received by recvmmsg, so the buffer provided
674    * must not be freed by the recv_cb callback.
675    */
676   UV_UDP_MMSG_CHUNK = 8,
677   /*
678    * Indicates that the buffer provided has been fully utilized by recvmmsg and
679    * that it should now be freed by the recv_cb callback. When this flag is set
680    * in uv_udp_recv_cb, nread will always be 0 and addr will always be NULL.
681    */
682   UV_UDP_MMSG_FREE = 16,
683   /*
684    * Indicates if IP_RECVERR/IPV6_RECVERR will be set when binding the handle.
685    * This sets IP_RECVERR for IPv4 and IPV6_RECVERR for IPv6 UDP sockets on
686    * Linux. This stops the Linux kernel from suppressing some ICMP error
687    * messages and enables full ICMP error reporting for faster failover.
688    * This flag is no-op on platforms other than Linux.
689    */
690   UV_UDP_LINUX_RECVERR = 32,
691   /*
692    * Indicates if SO_REUSEPORT will be set when binding the handle.
693    * This sets the SO_REUSEPORT socket option on supported platforms.
694    * Unlike UV_UDP_REUSEADDR, this flag will make multiple threads or
695    * processes that are binding to the same address and port "share"
696    * the port, which means incoming datagrams are distributed across
697    * the receiving sockets among threads or processes.
698    *
699    * This flag is available only on Linux 3.9+, DragonFlyBSD 3.6+,
700    * FreeBSD 12.0+, Solaris 11.4, and AIX 7.2.5+ for now.
701    */
702   UV_UDP_REUSEPORT = 64,
703   /*
704    * Indicates that recvmmsg should be used, if available.
705    */
706   UV_UDP_RECVMMSG = 256
707 };
708 
709 typedef void (*uv_udp_send_cb)(uv_udp_send_t* req, int status);
710 typedef void (*uv_udp_recv_cb)(uv_udp_t* handle,
711                                ssize_t nread,
712                                const uv_buf_t* buf,
713                                const struct sockaddr* addr,
714                                unsigned flags);
715 
716 /* uv_udp_t is a subclass of uv_handle_t. */
717 struct uv_udp_s {
718   UV_HANDLE_FIELDS
719   /* read-only */
720   /*
721    * Number of bytes queued for sending. This field strictly shows how much
722    * information is currently queued.
723    */
724   size_t send_queue_size;
725   /*
726    * Number of send requests currently in the queue awaiting to be processed.
727    */
728   size_t send_queue_count;
729   UV_UDP_PRIVATE_FIELDS
730 };
731 
732 /* uv_udp_send_t is a subclass of uv_req_t. */
733 struct uv_udp_send_s {
734   UV_REQ_FIELDS
735   uv_udp_t* handle;
736   uv_udp_send_cb cb;
737   UV_UDP_SEND_PRIVATE_FIELDS
738 };
739 
740 UV_EXTERN int uv_udp_init(uv_loop_t*, uv_udp_t* handle);
741 UV_EXTERN int uv_udp_init_ex(uv_loop_t*, uv_udp_t* handle, unsigned int flags);
742 UV_EXTERN int uv_udp_open(uv_udp_t* handle, uv_os_sock_t sock);
743 UV_EXTERN int uv_udp_bind(uv_udp_t* handle,
744                           const struct sockaddr* addr,
745                           unsigned int flags);
746 UV_EXTERN int uv_udp_connect(uv_udp_t* handle, const struct sockaddr* addr);
747 
748 UV_EXTERN int uv_udp_getpeername(const uv_udp_t* handle,
749                                  struct sockaddr* name,
750                                  int* namelen);
751 UV_EXTERN int uv_udp_getsockname(const uv_udp_t* handle,
752                                  struct sockaddr* name,
753                                  int* namelen);
754 UV_EXTERN int uv_udp_set_membership(uv_udp_t* handle,
755                                     const char* multicast_addr,
756                                     const char* interface_addr,
757                                     uv_membership membership);
758 UV_EXTERN int uv_udp_set_source_membership(uv_udp_t* handle,
759                                            const char* multicast_addr,
760                                            const char* interface_addr,
761                                            const char* source_addr,
762                                            uv_membership membership);
763 UV_EXTERN int uv_udp_set_multicast_loop(uv_udp_t* handle, int on);
764 UV_EXTERN int uv_udp_set_multicast_ttl(uv_udp_t* handle, int ttl);
765 UV_EXTERN int uv_udp_set_multicast_interface(uv_udp_t* handle,
766                                              const char* interface_addr);
767 UV_EXTERN int uv_udp_set_broadcast(uv_udp_t* handle, int on);
768 UV_EXTERN int uv_udp_set_ttl(uv_udp_t* handle, int ttl);
769 UV_EXTERN int uv_udp_send(uv_udp_send_t* req,
770                           uv_udp_t* handle,
771                           const uv_buf_t bufs[],
772                           unsigned int nbufs,
773                           const struct sockaddr* addr,
774                           uv_udp_send_cb send_cb);
775 UV_EXTERN int uv_udp_try_send(uv_udp_t* handle,
776                               const uv_buf_t bufs[],
777                               unsigned int nbufs,
778                               const struct sockaddr* addr);
779 UV_EXTERN int uv_udp_try_send2(uv_udp_t* handle,
780                                unsigned int count,
781                                uv_buf_t* bufs[/*count*/],
782                                unsigned int nbufs[/*count*/],
783                                struct sockaddr* addrs[/*count*/],
784                                unsigned int flags);
785 UV_EXTERN int uv_udp_recv_start(uv_udp_t* handle,
786                                 uv_alloc_cb alloc_cb,
787                                 uv_udp_recv_cb recv_cb);
788 UV_EXTERN int uv_udp_using_recvmmsg(const uv_udp_t* handle);
789 UV_EXTERN int uv_udp_recv_stop(uv_udp_t* handle);
790 UV_EXTERN size_t uv_udp_get_send_queue_size(const uv_udp_t* handle);
791 UV_EXTERN size_t uv_udp_get_send_queue_count(const uv_udp_t* handle);
792 
793 
794 /*
795  * uv_tty_t is a subclass of uv_stream_t.
796  *
797  * Representing a stream for the console.
798  */
799 struct uv_tty_s {
800   UV_HANDLE_FIELDS
801   UV_STREAM_FIELDS
802   UV_TTY_PRIVATE_FIELDS
803 };
804 
805 typedef enum {
806   /* Initial/normal terminal mode */
807   UV_TTY_MODE_NORMAL,
808   /* Raw input mode (On Windows, ENABLE_WINDOW_INPUT is also enabled) */
809   UV_TTY_MODE_RAW,
810   /* Binary-safe I/O mode for IPC (Unix-only) */
811   UV_TTY_MODE_IO
812 } uv_tty_mode_t;
813 
814 typedef enum {
815   /*
816    * The console supports handling of virtual terminal sequences
817    * (Windows10 new console, ConEmu)
818    */
819   UV_TTY_SUPPORTED,
820   /* The console cannot process the virtual terminal sequence.  (Legacy
821    * console)
822    */
823   UV_TTY_UNSUPPORTED
824 } uv_tty_vtermstate_t;
825 
826 
827 UV_EXTERN int uv_tty_init(uv_loop_t*, uv_tty_t*, uv_file fd, int readable);
828 UV_EXTERN int uv_tty_set_mode(uv_tty_t*, uv_tty_mode_t mode);
829 UV_EXTERN int uv_tty_reset_mode(void);
830 UV_EXTERN int uv_tty_get_winsize(uv_tty_t*, int* width, int* height);
831 UV_EXTERN void uv_tty_set_vterm_state(uv_tty_vtermstate_t state);
832 UV_EXTERN int uv_tty_get_vterm_state(uv_tty_vtermstate_t* state);
833 
834 #ifdef __cplusplus
835 extern "C++" {
836 
uv_tty_set_mode(uv_tty_t * handle,int mode)837 inline int uv_tty_set_mode(uv_tty_t* handle, int mode) {
838   return uv_tty_set_mode(handle, static_cast<uv_tty_mode_t>(mode));
839 }
840 
841 }
842 #endif
843 
844 UV_EXTERN uv_handle_type uv_guess_handle(uv_file file);
845 
846 enum {
847   UV_PIPE_NO_TRUNCATE = 1u << 0
848 };
849 
850 /*
851  * uv_pipe_t is a subclass of uv_stream_t.
852  *
853  * Representing a pipe stream or pipe server. On Windows this is a Named
854  * Pipe. On Unix this is a Unix domain socket.
855  */
856 struct uv_pipe_s {
857   UV_HANDLE_FIELDS
858   UV_STREAM_FIELDS
859   int ipc; /* non-zero if this pipe is used for passing handles */
860   UV_PIPE_PRIVATE_FIELDS
861 };
862 
863 UV_EXTERN int uv_pipe_init(uv_loop_t*, uv_pipe_t* handle, int ipc);
864 UV_EXTERN int uv_pipe_open(uv_pipe_t*, uv_file file);
865 UV_EXTERN int uv_pipe_bind(uv_pipe_t* handle, const char* name);
866 UV_EXTERN int uv_pipe_bind2(uv_pipe_t* handle,
867                             const char* name,
868                             size_t namelen,
869                             unsigned int flags);
870 UV_EXTERN void uv_pipe_connect(uv_connect_t* req,
871                                uv_pipe_t* handle,
872                                const char* name,
873                                uv_connect_cb cb);
874 UV_EXTERN int uv_pipe_connect2(uv_connect_t* req,
875                                uv_pipe_t* handle,
876                                const char* name,
877                                size_t namelen,
878                                unsigned int flags,
879                                uv_connect_cb cb);
880 UV_EXTERN int uv_pipe_getsockname(const uv_pipe_t* handle,
881                                   char* buffer,
882                                   size_t* size);
883 UV_EXTERN int uv_pipe_getpeername(const uv_pipe_t* handle,
884                                   char* buffer,
885                                   size_t* size);
886 UV_EXTERN void uv_pipe_pending_instances(uv_pipe_t* handle, int count);
887 UV_EXTERN int uv_pipe_pending_count(uv_pipe_t* handle);
888 UV_EXTERN uv_handle_type uv_pipe_pending_type(uv_pipe_t* handle);
889 UV_EXTERN int uv_pipe_chmod(uv_pipe_t* handle, int flags);
890 
891 
892 struct uv_poll_s {
893   UV_HANDLE_FIELDS
894   uv_poll_cb poll_cb;
895   UV_POLL_PRIVATE_FIELDS
896 };
897 
898 enum uv_poll_event {
899   UV_READABLE = 1,
900   UV_WRITABLE = 2,
901   UV_DISCONNECT = 4,
902   UV_PRIORITIZED = 8
903 };
904 
905 UV_EXTERN int uv_poll_init(uv_loop_t* loop, uv_poll_t* handle, int fd);
906 UV_EXTERN int uv_poll_init_socket(uv_loop_t* loop,
907                                   uv_poll_t* handle,
908                                   uv_os_sock_t socket);
909 UV_EXTERN int uv_poll_start(uv_poll_t* handle, int events, uv_poll_cb cb);
910 UV_EXTERN int uv_poll_stop(uv_poll_t* handle);
911 
912 
913 struct uv_prepare_s {
914   UV_HANDLE_FIELDS
915   UV_PREPARE_PRIVATE_FIELDS
916 };
917 
918 UV_EXTERN int uv_prepare_init(uv_loop_t*, uv_prepare_t* prepare);
919 UV_EXTERN int uv_prepare_start(uv_prepare_t* prepare, uv_prepare_cb cb);
920 UV_EXTERN int uv_prepare_stop(uv_prepare_t* prepare);
921 
922 
923 struct uv_check_s {
924   UV_HANDLE_FIELDS
925   UV_CHECK_PRIVATE_FIELDS
926 };
927 
928 UV_EXTERN int uv_check_init(uv_loop_t*, uv_check_t* check);
929 UV_EXTERN int uv_check_start(uv_check_t* check, uv_check_cb cb);
930 UV_EXTERN int uv_check_stop(uv_check_t* check);
931 
932 
933 struct uv_idle_s {
934   UV_HANDLE_FIELDS
935   UV_IDLE_PRIVATE_FIELDS
936 };
937 
938 UV_EXTERN int uv_idle_init(uv_loop_t*, uv_idle_t* idle);
939 UV_EXTERN int uv_idle_start(uv_idle_t* idle, uv_idle_cb cb);
940 UV_EXTERN int uv_idle_stop(uv_idle_t* idle);
941 
942 
943 struct uv_async_s {
944   UV_HANDLE_FIELDS
945   UV_ASYNC_PRIVATE_FIELDS
946 };
947 
948 UV_EXTERN int uv_async_init(uv_loop_t*,
949                             uv_async_t* async,
950                             uv_async_cb async_cb);
951 UV_EXTERN int uv_async_send(uv_async_t* async);
952 
953 
954 /*
955  * uv_timer_t is a subclass of uv_handle_t.
956  *
957  * Used to get woken up at a specified time in the future.
958  */
959 struct uv_timer_s {
960   UV_HANDLE_FIELDS
961   UV_TIMER_PRIVATE_FIELDS
962 };
963 
964 UV_EXTERN int uv_timer_init(uv_loop_t*, uv_timer_t* handle);
965 UV_EXTERN int uv_timer_start(uv_timer_t* handle,
966                              uv_timer_cb cb,
967                              uint64_t timeout,
968                              uint64_t repeat);
969 UV_EXTERN int uv_timer_stop(uv_timer_t* handle);
970 UV_EXTERN int uv_timer_again(uv_timer_t* handle);
971 UV_EXTERN void uv_timer_set_repeat(uv_timer_t* handle, uint64_t repeat);
972 UV_EXTERN uint64_t uv_timer_get_repeat(const uv_timer_t* handle);
973 UV_EXTERN uint64_t uv_timer_get_due_in(const uv_timer_t* handle);
974 
975 
976 /*
977  * uv_getaddrinfo_t is a subclass of uv_req_t.
978  *
979  * Request object for uv_getaddrinfo.
980  */
981 struct uv_getaddrinfo_s {
982   UV_REQ_FIELDS
983   /* read-only */
984   uv_loop_t* loop;
985   /* struct addrinfo* addrinfo is marked as private, but it really isn't. */
986   UV_GETADDRINFO_PRIVATE_FIELDS
987 };
988 
989 
990 UV_EXTERN int uv_getaddrinfo(uv_loop_t* loop,
991                              uv_getaddrinfo_t* req,
992                              uv_getaddrinfo_cb getaddrinfo_cb,
993                              const char* node,
994                              const char* service,
995                              const struct addrinfo* hints);
996 UV_EXTERN void uv_freeaddrinfo(struct addrinfo* ai);
997 
998 
999 /*
1000 * uv_getnameinfo_t is a subclass of uv_req_t.
1001 *
1002 * Request object for uv_getnameinfo.
1003 */
1004 struct uv_getnameinfo_s {
1005   UV_REQ_FIELDS
1006   /* read-only */
1007   uv_loop_t* loop;
1008   /* host and service are marked as private, but they really aren't. */
1009   UV_GETNAMEINFO_PRIVATE_FIELDS
1010 };
1011 
1012 UV_EXTERN int uv_getnameinfo(uv_loop_t* loop,
1013                              uv_getnameinfo_t* req,
1014                              uv_getnameinfo_cb getnameinfo_cb,
1015                              const struct sockaddr* addr,
1016                              int flags);
1017 
1018 
1019 /* uv_spawn() options. */
1020 typedef enum {
1021   UV_IGNORE         = 0x00,
1022   UV_CREATE_PIPE    = 0x01,
1023   UV_INHERIT_FD     = 0x02,
1024   UV_INHERIT_STREAM = 0x04,
1025 
1026   /*
1027    * When UV_CREATE_PIPE is specified, UV_READABLE_PIPE and UV_WRITABLE_PIPE
1028    * determine the direction of flow, from the child process' perspective. Both
1029    * flags may be specified to create a duplex data stream.
1030    */
1031   UV_READABLE_PIPE  = 0x10,
1032   UV_WRITABLE_PIPE  = 0x20,
1033 
1034   /*
1035    * When UV_CREATE_PIPE is specified, specifying UV_NONBLOCK_PIPE opens the
1036    * handle in non-blocking mode in the child. This may cause loss of data,
1037    * if the child is not designed to handle to encounter this mode,
1038    * but can also be significantly more efficient.
1039    */
1040   UV_NONBLOCK_PIPE  = 0x40,
1041   UV_OVERLAPPED_PIPE = 0x40 /* old name, for compatibility */
1042 } uv_stdio_flags;
1043 
1044 typedef struct uv_stdio_container_s {
1045   uv_stdio_flags flags;
1046 
1047   union {
1048     uv_stream_t* stream;
1049     int fd;
1050   } data;
1051 } uv_stdio_container_t;
1052 
1053 typedef struct uv_process_options_s {
1054   uv_exit_cb exit_cb; /* Called after the process exits. */
1055   const char* file;   /* Path to program to execute. */
1056   /*
1057    * Command line arguments. args[0] should be the path to the program. On
1058    * Windows this uses CreateProcess which concatenates the arguments into a
1059    * string this can cause some strange errors. See the note at
1060    * windows_verbatim_arguments.
1061    */
1062   char** args;
1063   /*
1064    * This will be set as the environ variable in the subprocess. If this is
1065    * NULL then the parents environ will be used.
1066    */
1067   char** env;
1068   /*
1069    * If non-null this represents a directory the subprocess should execute
1070    * in. Stands for current working directory.
1071    */
1072   const char* cwd;
1073   /*
1074    * Various flags that control how uv_spawn() behaves. See the definition of
1075    * `enum uv_process_flags` below.
1076    */
1077   unsigned int flags;
1078   /*
1079    * The `stdio` field points to an array of uv_stdio_container_t structs that
1080    * describe the file descriptors that will be made available to the child
1081    * process. The convention is that stdio[0] points to stdin, fd 1 is used for
1082    * stdout, and fd 2 is stderr.
1083    *
1084    * Note that on windows file descriptors greater than 2 are available to the
1085    * child process only if the child processes uses the MSVCRT runtime.
1086    */
1087   int stdio_count;
1088   uv_stdio_container_t* stdio;
1089   /*
1090    * Libuv can change the child process' user/group id. This happens only when
1091    * the appropriate bits are set in the flags fields. This is not supported on
1092    * windows; uv_spawn() will fail and set the error to UV_ENOTSUP.
1093    */
1094   uv_uid_t uid;
1095   uv_gid_t gid;
1096 } uv_process_options_t;
1097 
1098 /*
1099  * These are the flags that can be used for the uv_process_options.flags field.
1100  */
1101 enum uv_process_flags {
1102   /*
1103    * Set the child process' user id. The user id is supplied in the `uid` field
1104    * of the options struct. This does not work on windows; setting this flag
1105    * will cause uv_spawn() to fail.
1106    */
1107   UV_PROCESS_SETUID = (1 << 0),
1108   /*
1109    * Set the child process' group id. The user id is supplied in the `gid`
1110    * field of the options struct. This does not work on windows; setting this
1111    * flag will cause uv_spawn() to fail.
1112    */
1113   UV_PROCESS_SETGID = (1 << 1),
1114   /*
1115    * Do not wrap any arguments in quotes, or perform any other escaping, when
1116    * converting the argument list into a command line string. This option is
1117    * only meaningful on Windows systems. On Unix it is silently ignored.
1118    */
1119   UV_PROCESS_WINDOWS_VERBATIM_ARGUMENTS = (1 << 2),
1120   /*
1121    * Spawn the child process in a detached state - this will make it a process
1122    * group leader, and will effectively enable the child to keep running after
1123    * the parent exits.  Note that the child process will still keep the
1124    * parent's event loop alive unless the parent process calls uv_unref() on
1125    * the child's process handle.
1126    */
1127   UV_PROCESS_DETACHED = (1 << 3),
1128   /*
1129    * Hide the subprocess window that would normally be created. This option is
1130    * only meaningful on Windows systems. On Unix it is silently ignored.
1131    */
1132   UV_PROCESS_WINDOWS_HIDE = (1 << 4),
1133   /*
1134    * Hide the subprocess console window that would normally be created. This
1135    * option is only meaningful on Windows systems. On Unix it is silently
1136    * ignored.
1137    */
1138   UV_PROCESS_WINDOWS_HIDE_CONSOLE = (1 << 5),
1139   /*
1140    * Hide the subprocess GUI window that would normally be created. This
1141    * option is only meaningful on Windows systems. On Unix it is silently
1142    * ignored.
1143    */
1144   UV_PROCESS_WINDOWS_HIDE_GUI = (1 << 6),
1145   /*
1146    * On Windows, if the path to the program to execute, specified in
1147    * uv_process_options_t's file field, has a directory component,
1148    * search for the exact file name before trying variants with
1149    * extensions like '.exe' or '.cmd'.
1150    */
1151   UV_PROCESS_WINDOWS_FILE_PATH_EXACT_NAME = (1 << 7)
1152 };
1153 
1154 /*
1155  * uv_process_t is a subclass of uv_handle_t.
1156  */
1157 struct uv_process_s {
1158   UV_HANDLE_FIELDS
1159   uv_exit_cb exit_cb;
1160   int pid;
1161   UV_PROCESS_PRIVATE_FIELDS
1162 };
1163 
1164 UV_EXTERN int uv_spawn(uv_loop_t* loop,
1165                        uv_process_t* handle,
1166                        const uv_process_options_t* options);
1167 UV_EXTERN int uv_process_kill(uv_process_t*, int signum);
1168 UV_EXTERN int uv_kill(int pid, int signum);
1169 UV_EXTERN uv_pid_t uv_process_get_pid(const uv_process_t*);
1170 
1171 
1172 /*
1173  * uv_work_t is a subclass of uv_req_t.
1174  */
1175 struct uv_work_s {
1176   UV_REQ_FIELDS
1177   uv_loop_t* loop;
1178   uv_work_cb work_cb;
1179   uv_after_work_cb after_work_cb;
1180   UV_WORK_PRIVATE_FIELDS
1181 };
1182 
1183 UV_EXTERN int uv_queue_work(uv_loop_t* loop,
1184                             uv_work_t* req,
1185                             uv_work_cb work_cb,
1186                             uv_after_work_cb after_work_cb);
1187 
1188 UV_EXTERN int uv_cancel(uv_req_t* req);
1189 
1190 
1191 struct uv_cpu_times_s {
1192   uint64_t user; /* milliseconds */
1193   uint64_t nice; /* milliseconds */
1194   uint64_t sys; /* milliseconds */
1195   uint64_t idle; /* milliseconds */
1196   uint64_t irq; /* milliseconds */
1197 };
1198 
1199 struct uv_cpu_info_s {
1200   char* model;
1201   int speed;
1202   struct uv_cpu_times_s cpu_times;
1203 };
1204 
1205 struct uv_interface_address_s {
1206   char* name;
1207   char phys_addr[6];
1208   int is_internal;
1209   union {
1210     struct sockaddr_in address4;
1211     struct sockaddr_in6 address6;
1212   } address;
1213   union {
1214     struct sockaddr_in netmask4;
1215     struct sockaddr_in6 netmask6;
1216   } netmask;
1217 };
1218 
1219 struct uv_passwd_s {
1220   char* username;
1221   unsigned long uid;
1222   unsigned long gid;
1223   char* shell;
1224   char* homedir;
1225 };
1226 
1227 struct uv_group_s {
1228   char* groupname;
1229   unsigned long gid;
1230   char** members;
1231 };
1232 
1233 struct uv_utsname_s {
1234   char sysname[256];
1235   char release[256];
1236   char version[256];
1237   char machine[256];
1238   /* This struct does not contain the nodename and domainname fields present in
1239      the utsname type. domainname is a GNU extension. Both fields are referred
1240      to as meaningless in the docs. */
1241 };
1242 
1243 struct uv_statfs_s {
1244   uint64_t f_type;
1245   uint64_t f_bsize;
1246   uint64_t f_blocks;
1247   uint64_t f_bfree;
1248   uint64_t f_bavail;
1249   uint64_t f_files;
1250   uint64_t f_ffree;
1251   uint64_t f_spare[4];
1252 };
1253 
1254 typedef enum {
1255   UV_DIRENT_UNKNOWN,
1256   UV_DIRENT_FILE,
1257   UV_DIRENT_DIR,
1258   UV_DIRENT_LINK,
1259   UV_DIRENT_FIFO,
1260   UV_DIRENT_SOCKET,
1261   UV_DIRENT_CHAR,
1262   UV_DIRENT_BLOCK
1263 } uv_dirent_type_t;
1264 
1265 struct uv_dirent_s {
1266   const char* name;
1267   uv_dirent_type_t type;
1268 };
1269 
1270 UV_EXTERN char** uv_setup_args(int argc, char** argv);
1271 UV_EXTERN int uv_get_process_title(char* buffer, size_t size);
1272 UV_EXTERN int uv_set_process_title(const char* title);
1273 UV_EXTERN int uv_resident_set_memory(size_t* rss);
1274 UV_EXTERN int uv_uptime(double* uptime);
1275 UV_EXTERN uv_os_fd_t uv_get_osfhandle(int fd);
1276 UV_EXTERN int uv_open_osfhandle(uv_os_fd_t os_fd);
1277 
1278 typedef struct {
1279    uv_timeval_t ru_utime; /* user CPU time used */
1280    uv_timeval_t ru_stime; /* system CPU time used */
1281    uint64_t ru_maxrss;    /* maximum resident set size */
1282    uint64_t ru_ixrss;     /* integral shared memory size */
1283    uint64_t ru_idrss;     /* integral unshared data size */
1284    uint64_t ru_isrss;     /* integral unshared stack size */
1285    uint64_t ru_minflt;    /* page reclaims (soft page faults) */
1286    uint64_t ru_majflt;    /* page faults (hard page faults) */
1287    uint64_t ru_nswap;     /* swaps */
1288    uint64_t ru_inblock;   /* block input operations */
1289    uint64_t ru_oublock;   /* block output operations */
1290    uint64_t ru_msgsnd;    /* IPC messages sent */
1291    uint64_t ru_msgrcv;    /* IPC messages received */
1292    uint64_t ru_nsignals;  /* signals received */
1293    uint64_t ru_nvcsw;     /* voluntary context switches */
1294    uint64_t ru_nivcsw;    /* involuntary context switches */
1295 } uv_rusage_t;
1296 
1297 UV_EXTERN int uv_getrusage(uv_rusage_t* rusage);
1298 
1299 UV_EXTERN int uv_os_homedir(char* buffer, size_t* size);
1300 UV_EXTERN int uv_os_tmpdir(char* buffer, size_t* size);
1301 UV_EXTERN int uv_os_get_passwd(uv_passwd_t* pwd);
1302 UV_EXTERN void uv_os_free_passwd(uv_passwd_t* pwd);
1303 UV_EXTERN int uv_os_get_passwd2(uv_passwd_t* pwd, uv_uid_t uid);
1304 UV_EXTERN int uv_os_get_group(uv_group_t* grp, uv_uid_t gid);
1305 UV_EXTERN void uv_os_free_group(uv_group_t* grp);
1306 UV_EXTERN uv_pid_t uv_os_getpid(void);
1307 UV_EXTERN uv_pid_t uv_os_getppid(void);
1308 
1309 #if defined(__PASE__)
1310 /* On IBM i PASE, the highest process priority is -10 */
1311 # define UV_PRIORITY_LOW 39          /* RUNPTY(99) */
1312 # define UV_PRIORITY_BELOW_NORMAL 15 /* RUNPTY(50) */
1313 # define UV_PRIORITY_NORMAL 0        /* RUNPTY(20) */
1314 # define UV_PRIORITY_ABOVE_NORMAL -4 /* RUNTY(12) */
1315 # define UV_PRIORITY_HIGH -7         /* RUNPTY(6) */
1316 # define UV_PRIORITY_HIGHEST -10     /* RUNPTY(1) */
1317 #else
1318 # define UV_PRIORITY_LOW 19
1319 # define UV_PRIORITY_BELOW_NORMAL 10
1320 # define UV_PRIORITY_NORMAL 0
1321 # define UV_PRIORITY_ABOVE_NORMAL -7
1322 # define UV_PRIORITY_HIGH -14
1323 # define UV_PRIORITY_HIGHEST -20
1324 #endif
1325 
1326 UV_EXTERN int uv_os_getpriority(uv_pid_t pid, int* priority);
1327 UV_EXTERN int uv_os_setpriority(uv_pid_t pid, int priority);
1328 
1329 enum {
1330   UV_THREAD_PRIORITY_HIGHEST = 2,
1331   UV_THREAD_PRIORITY_ABOVE_NORMAL = 1,
1332   UV_THREAD_PRIORITY_NORMAL = 0,
1333   UV_THREAD_PRIORITY_BELOW_NORMAL = -1,
1334   UV_THREAD_PRIORITY_LOWEST = -2,
1335 };
1336 
1337 UV_EXTERN int uv_thread_getpriority(uv_thread_t tid, int* priority);
1338 UV_EXTERN int uv_thread_setpriority(uv_thread_t tid, int priority);
1339 
1340 UV_EXTERN unsigned int uv_available_parallelism(void);
1341 UV_EXTERN int uv_cpu_info(uv_cpu_info_t** cpu_infos, int* count);
1342 UV_EXTERN void uv_free_cpu_info(uv_cpu_info_t* cpu_infos, int count);
1343 UV_EXTERN int uv_cpumask_size(void);
1344 
1345 UV_EXTERN int uv_interface_addresses(uv_interface_address_t** addresses,
1346                                      int* count);
1347 UV_EXTERN void uv_free_interface_addresses(uv_interface_address_t* addresses,
1348                                            int count);
1349 
1350 struct uv_env_item_s {
1351   char* name;
1352   char* value;
1353 };
1354 
1355 UV_EXTERN int uv_os_environ(uv_env_item_t** envitems, int* count);
1356 UV_EXTERN void uv_os_free_environ(uv_env_item_t* envitems, int count);
1357 UV_EXTERN int uv_os_getenv(const char* name, char* buffer, size_t* size);
1358 UV_EXTERN int uv_os_setenv(const char* name, const char* value);
1359 UV_EXTERN int uv_os_unsetenv(const char* name);
1360 
1361 #ifdef MAXHOSTNAMELEN
1362 # define UV_MAXHOSTNAMESIZE (MAXHOSTNAMELEN + 1)
1363 #else
1364   /*
1365     Fallback for the maximum hostname size, including the null terminator. The
1366     Windows gethostname() documentation states that 256 bytes will always be
1367     large enough to hold the null-terminated hostname.
1368   */
1369 # define UV_MAXHOSTNAMESIZE 256
1370 #endif
1371 
1372 UV_EXTERN int uv_os_gethostname(char* buffer, size_t* size);
1373 
1374 UV_EXTERN int uv_os_uname(uv_utsname_t* buffer);
1375 
1376 struct uv_metrics_s {
1377   uint64_t loop_count;
1378   uint64_t events;
1379   uint64_t events_waiting;
1380   /* private */
1381   uint64_t* reserved[13];
1382 };
1383 
1384 UV_EXTERN int uv_metrics_info(uv_loop_t* loop, uv_metrics_t* metrics);
1385 UV_EXTERN uint64_t uv_metrics_idle_time(uv_loop_t* loop);
1386 
1387 typedef enum {
1388   UV_FS_UNKNOWN = -1,
1389   UV_FS_CUSTOM,
1390   UV_FS_OPEN,
1391   UV_FS_CLOSE,
1392   UV_FS_READ,
1393   UV_FS_WRITE,
1394   UV_FS_SENDFILE,
1395   UV_FS_STAT,
1396   UV_FS_LSTAT,
1397   UV_FS_FSTAT,
1398   UV_FS_FTRUNCATE,
1399   UV_FS_UTIME,
1400   UV_FS_FUTIME,
1401   UV_FS_ACCESS,
1402   UV_FS_CHMOD,
1403   UV_FS_FCHMOD,
1404   UV_FS_FSYNC,
1405   UV_FS_FDATASYNC,
1406   UV_FS_UNLINK,
1407   UV_FS_RMDIR,
1408   UV_FS_MKDIR,
1409   UV_FS_MKDTEMP,
1410   UV_FS_RENAME,
1411   UV_FS_SCANDIR,
1412   UV_FS_LINK,
1413   UV_FS_SYMLINK,
1414   UV_FS_READLINK,
1415   UV_FS_CHOWN,
1416   UV_FS_FCHOWN,
1417   UV_FS_REALPATH,
1418   UV_FS_COPYFILE,
1419   UV_FS_LCHOWN,
1420   UV_FS_OPENDIR,
1421   UV_FS_READDIR,
1422   UV_FS_CLOSEDIR,
1423   UV_FS_STATFS,
1424   UV_FS_MKSTEMP,
1425   UV_FS_LUTIME
1426 } uv_fs_type;
1427 
1428 struct uv_dir_s {
1429   uv_dirent_t* dirents;
1430   size_t nentries;
1431   void* reserved[4];
1432   UV_DIR_PRIVATE_FIELDS
1433 };
1434 
1435 /* uv_fs_t is a subclass of uv_req_t. */
1436 struct uv_fs_s {
1437   UV_REQ_FIELDS
1438   uv_fs_type fs_type;
1439   uv_loop_t* loop;
1440   uv_fs_cb cb;
1441   ssize_t result;
1442   void* ptr;
1443   const char* path;
1444   uv_stat_t statbuf;  /* Stores the result of uv_fs_stat() and uv_fs_fstat(). */
1445   UV_FS_PRIVATE_FIELDS
1446 };
1447 
1448 UV_EXTERN uv_fs_type uv_fs_get_type(const uv_fs_t*);
1449 UV_EXTERN ssize_t uv_fs_get_result(const uv_fs_t*);
1450 UV_EXTERN int uv_fs_get_system_error(const uv_fs_t*);
1451 UV_EXTERN void* uv_fs_get_ptr(const uv_fs_t*);
1452 UV_EXTERN const char* uv_fs_get_path(const uv_fs_t*);
1453 UV_EXTERN uv_stat_t* uv_fs_get_statbuf(uv_fs_t*);
1454 
1455 UV_EXTERN void uv_fs_req_cleanup(uv_fs_t* req);
1456 UV_EXTERN int uv_fs_close(uv_loop_t* loop,
1457                           uv_fs_t* req,
1458                           uv_file file,
1459                           uv_fs_cb cb);
1460 UV_EXTERN int uv_fs_open(uv_loop_t* loop,
1461                          uv_fs_t* req,
1462                          const char* path,
1463                          int flags,
1464                          int mode,
1465                          uv_fs_cb cb);
1466 UV_EXTERN int uv_fs_read(uv_loop_t* loop,
1467                          uv_fs_t* req,
1468                          uv_file file,
1469                          const uv_buf_t bufs[],
1470                          unsigned int nbufs,
1471                          int64_t offset,
1472                          uv_fs_cb cb);
1473 UV_EXTERN int uv_fs_unlink(uv_loop_t* loop,
1474                            uv_fs_t* req,
1475                            const char* path,
1476                            uv_fs_cb cb);
1477 UV_EXTERN int uv_fs_write(uv_loop_t* loop,
1478                           uv_fs_t* req,
1479                           uv_file file,
1480                           const uv_buf_t bufs[],
1481                           unsigned int nbufs,
1482                           int64_t offset,
1483                           uv_fs_cb cb);
1484 /*
1485  * This flag can be used with uv_fs_copyfile() to return an error if the
1486  * destination already exists.
1487  */
1488 #define UV_FS_COPYFILE_EXCL   0x0001
1489 
1490 /*
1491  * This flag can be used with uv_fs_copyfile() to attempt to create a reflink.
1492  * If copy-on-write is not supported, a fallback copy mechanism is used.
1493  */
1494 #define UV_FS_COPYFILE_FICLONE 0x0002
1495 
1496 /*
1497  * This flag can be used with uv_fs_copyfile() to attempt to create a reflink.
1498  * If copy-on-write is not supported, an error is returned.
1499  */
1500 #define UV_FS_COPYFILE_FICLONE_FORCE 0x0004
1501 
1502 UV_EXTERN int uv_fs_copyfile(uv_loop_t* loop,
1503                              uv_fs_t* req,
1504                              const char* path,
1505                              const char* new_path,
1506                              int flags,
1507                              uv_fs_cb cb);
1508 UV_EXTERN int uv_fs_mkdir(uv_loop_t* loop,
1509                           uv_fs_t* req,
1510                           const char* path,
1511                           int mode,
1512                           uv_fs_cb cb);
1513 UV_EXTERN int uv_fs_mkdtemp(uv_loop_t* loop,
1514                             uv_fs_t* req,
1515                             const char* tpl,
1516                             uv_fs_cb cb);
1517 UV_EXTERN int uv_fs_mkstemp(uv_loop_t* loop,
1518                             uv_fs_t* req,
1519                             const char* tpl,
1520                             uv_fs_cb cb);
1521 UV_EXTERN int uv_fs_rmdir(uv_loop_t* loop,
1522                           uv_fs_t* req,
1523                           const char* path,
1524                           uv_fs_cb cb);
1525 UV_EXTERN int uv_fs_scandir(uv_loop_t* loop,
1526                             uv_fs_t* req,
1527                             const char* path,
1528                             int flags,
1529                             uv_fs_cb cb);
1530 UV_EXTERN int uv_fs_scandir_next(uv_fs_t* req,
1531                                  uv_dirent_t* ent);
1532 UV_EXTERN int uv_fs_opendir(uv_loop_t* loop,
1533                             uv_fs_t* req,
1534                             const char* path,
1535                             uv_fs_cb cb);
1536 UV_EXTERN int uv_fs_readdir(uv_loop_t* loop,
1537                             uv_fs_t* req,
1538                             uv_dir_t* dir,
1539                             uv_fs_cb cb);
1540 UV_EXTERN int uv_fs_closedir(uv_loop_t* loop,
1541                              uv_fs_t* req,
1542                              uv_dir_t* dir,
1543                              uv_fs_cb cb);
1544 UV_EXTERN int uv_fs_stat(uv_loop_t* loop,
1545                          uv_fs_t* req,
1546                          const char* path,
1547                          uv_fs_cb cb);
1548 UV_EXTERN int uv_fs_fstat(uv_loop_t* loop,
1549                           uv_fs_t* req,
1550                           uv_file file,
1551                           uv_fs_cb cb);
1552 UV_EXTERN int uv_fs_rename(uv_loop_t* loop,
1553                            uv_fs_t* req,
1554                            const char* path,
1555                            const char* new_path,
1556                            uv_fs_cb cb);
1557 UV_EXTERN int uv_fs_fsync(uv_loop_t* loop,
1558                           uv_fs_t* req,
1559                           uv_file file,
1560                           uv_fs_cb cb);
1561 UV_EXTERN int uv_fs_fdatasync(uv_loop_t* loop,
1562                               uv_fs_t* req,
1563                               uv_file file,
1564                               uv_fs_cb cb);
1565 UV_EXTERN int uv_fs_ftruncate(uv_loop_t* loop,
1566                               uv_fs_t* req,
1567                               uv_file file,
1568                               int64_t offset,
1569                               uv_fs_cb cb);
1570 UV_EXTERN int uv_fs_sendfile(uv_loop_t* loop,
1571                              uv_fs_t* req,
1572                              uv_file out_fd,
1573                              uv_file in_fd,
1574                              int64_t in_offset,
1575                              size_t length,
1576                              uv_fs_cb cb);
1577 UV_EXTERN int uv_fs_access(uv_loop_t* loop,
1578                            uv_fs_t* req,
1579                            const char* path,
1580                            int mode,
1581                            uv_fs_cb cb);
1582 UV_EXTERN int uv_fs_chmod(uv_loop_t* loop,
1583                           uv_fs_t* req,
1584                           const char* path,
1585                           int mode,
1586                           uv_fs_cb cb);
1587 UV_EXTERN int uv_fs_utime(uv_loop_t* loop,
1588                           uv_fs_t* req,
1589                           const char* path,
1590                           double atime,
1591                           double mtime,
1592                           uv_fs_cb cb);
1593 UV_EXTERN int uv_fs_futime(uv_loop_t* loop,
1594                            uv_fs_t* req,
1595                            uv_file file,
1596                            double atime,
1597                            double mtime,
1598                            uv_fs_cb cb);
1599 UV_EXTERN int uv_fs_lutime(uv_loop_t* loop,
1600                            uv_fs_t* req,
1601                            const char* path,
1602                            double atime,
1603                            double mtime,
1604                            uv_fs_cb cb);
1605 UV_EXTERN int uv_fs_lstat(uv_loop_t* loop,
1606                           uv_fs_t* req,
1607                           const char* path,
1608                           uv_fs_cb cb);
1609 UV_EXTERN int uv_fs_link(uv_loop_t* loop,
1610                          uv_fs_t* req,
1611                          const char* path,
1612                          const char* new_path,
1613                          uv_fs_cb cb);
1614 
1615 /*
1616  * This flag can be used with uv_fs_symlink() on Windows to specify whether
1617  * path argument points to a directory.
1618  */
1619 #define UV_FS_SYMLINK_DIR          0x0001
1620 
1621 /*
1622  * This flag can be used with uv_fs_symlink() on Windows to specify whether
1623  * the symlink is to be created using junction points.
1624  */
1625 #define UV_FS_SYMLINK_JUNCTION     0x0002
1626 
1627 UV_EXTERN int uv_fs_symlink(uv_loop_t* loop,
1628                             uv_fs_t* req,
1629                             const char* path,
1630                             const char* new_path,
1631                             int flags,
1632                             uv_fs_cb cb);
1633 UV_EXTERN int uv_fs_readlink(uv_loop_t* loop,
1634                              uv_fs_t* req,
1635                              const char* path,
1636                              uv_fs_cb cb);
1637 UV_EXTERN int uv_fs_realpath(uv_loop_t* loop,
1638                              uv_fs_t* req,
1639                              const char* path,
1640                              uv_fs_cb cb);
1641 UV_EXTERN int uv_fs_fchmod(uv_loop_t* loop,
1642                            uv_fs_t* req,
1643                            uv_file file,
1644                            int mode,
1645                            uv_fs_cb cb);
1646 UV_EXTERN int uv_fs_chown(uv_loop_t* loop,
1647                           uv_fs_t* req,
1648                           const char* path,
1649                           uv_uid_t uid,
1650                           uv_gid_t gid,
1651                           uv_fs_cb cb);
1652 UV_EXTERN int uv_fs_fchown(uv_loop_t* loop,
1653                            uv_fs_t* req,
1654                            uv_file file,
1655                            uv_uid_t uid,
1656                            uv_gid_t gid,
1657                            uv_fs_cb cb);
1658 UV_EXTERN int uv_fs_lchown(uv_loop_t* loop,
1659                            uv_fs_t* req,
1660                            const char* path,
1661                            uv_uid_t uid,
1662                            uv_gid_t gid,
1663                            uv_fs_cb cb);
1664 UV_EXTERN int uv_fs_statfs(uv_loop_t* loop,
1665                            uv_fs_t* req,
1666                            const char* path,
1667                            uv_fs_cb cb);
1668 
1669 
1670 enum uv_fs_event {
1671   UV_RENAME = 1,
1672   UV_CHANGE = 2
1673 };
1674 
1675 
1676 struct uv_fs_event_s {
1677   UV_HANDLE_FIELDS
1678   /* private */
1679   char* path;
1680   UV_FS_EVENT_PRIVATE_FIELDS
1681 };
1682 
1683 
1684 /*
1685  * uv_fs_stat() based polling file watcher.
1686  */
1687 struct uv_fs_poll_s {
1688   UV_HANDLE_FIELDS
1689   /* Private, don't touch. */
1690   void* poll_ctx;
1691 };
1692 
1693 UV_EXTERN int uv_fs_poll_init(uv_loop_t* loop, uv_fs_poll_t* handle);
1694 UV_EXTERN int uv_fs_poll_start(uv_fs_poll_t* handle,
1695                                uv_fs_poll_cb poll_cb,
1696                                const char* path,
1697                                unsigned int interval);
1698 UV_EXTERN int uv_fs_poll_stop(uv_fs_poll_t* handle);
1699 UV_EXTERN int uv_fs_poll_getpath(uv_fs_poll_t* handle,
1700                                  char* buffer,
1701                                  size_t* size);
1702 
1703 
1704 struct uv_signal_s {
1705   UV_HANDLE_FIELDS
1706   uv_signal_cb signal_cb;
1707   int signum;
1708   UV_SIGNAL_PRIVATE_FIELDS
1709 };
1710 
1711 UV_EXTERN int uv_signal_init(uv_loop_t* loop, uv_signal_t* handle);
1712 UV_EXTERN int uv_signal_start(uv_signal_t* handle,
1713                               uv_signal_cb signal_cb,
1714                               int signum);
1715 UV_EXTERN int uv_signal_start_oneshot(uv_signal_t* handle,
1716                                       uv_signal_cb signal_cb,
1717                                       int signum);
1718 UV_EXTERN int uv_signal_stop(uv_signal_t* handle);
1719 
1720 UV_EXTERN void uv_loadavg(double avg[3]);
1721 
1722 
1723 /*
1724  * Flags to be passed to uv_fs_event_start().
1725  */
1726 enum uv_fs_event_flags {
1727   /*
1728    * By default, if the fs event watcher is given a directory name, we will
1729    * watch for all events in that directory. This flags overrides this behavior
1730    * and makes fs_event report only changes to the directory entry itself. This
1731    * flag does not affect individual files watched.
1732    * This flag is currently not implemented yet on any backend.
1733    */
1734   UV_FS_EVENT_WATCH_ENTRY = 1,
1735 
1736   /*
1737    * By default uv_fs_event will try to use a kernel interface such as inotify
1738    * or kqueue to detect events. This may not work on remote filesystems such
1739    * as NFS mounts. This flag makes fs_event fall back to calling stat() on a
1740    * regular interval.
1741    * This flag is currently not implemented yet on any backend.
1742    */
1743   UV_FS_EVENT_STAT = 2,
1744 
1745   /*
1746    * By default, event watcher, when watching directory, is not registering
1747    * (is ignoring) changes in it's subdirectories.
1748    * This flag will override this behaviour on platforms that support it.
1749    */
1750   UV_FS_EVENT_RECURSIVE = 4
1751 };
1752 
1753 
1754 UV_EXTERN int uv_fs_event_init(uv_loop_t* loop, uv_fs_event_t* handle);
1755 UV_EXTERN int uv_fs_event_start(uv_fs_event_t* handle,
1756                                 uv_fs_event_cb cb,
1757                                 const char* path,
1758                                 unsigned int flags);
1759 UV_EXTERN int uv_fs_event_stop(uv_fs_event_t* handle);
1760 UV_EXTERN int uv_fs_event_getpath(uv_fs_event_t* handle,
1761                                   char* buffer,
1762                                   size_t* size);
1763 
1764 UV_EXTERN int uv_ip4_addr(const char* ip, int port, struct sockaddr_in* addr);
1765 UV_EXTERN int uv_ip6_addr(const char* ip, int port, struct sockaddr_in6* addr);
1766 
1767 UV_EXTERN int uv_ip4_name(const struct sockaddr_in* src, char* dst, size_t size);
1768 UV_EXTERN int uv_ip6_name(const struct sockaddr_in6* src, char* dst, size_t size);
1769 UV_EXTERN int uv_ip_name(const struct sockaddr* src, char* dst, size_t size);
1770 
1771 UV_EXTERN int uv_inet_ntop(int af, const void* src, char* dst, size_t size);
1772 UV_EXTERN int uv_inet_pton(int af, const char* src, void* dst);
1773 
1774 
1775 struct uv_random_s {
1776   UV_REQ_FIELDS
1777   /* read-only */
1778   uv_loop_t* loop;
1779   /* private */
1780   int status;
1781   void* buf;
1782   size_t buflen;
1783   uv_random_cb cb;
1784   struct uv__work work_req;
1785 };
1786 
1787 UV_EXTERN int uv_random(uv_loop_t* loop,
1788                         uv_random_t* req,
1789                         void *buf,
1790                         size_t buflen,
1791                         unsigned flags,  /* For future extension; must be 0. */
1792                         uv_random_cb cb);
1793 
1794 #if defined(IF_NAMESIZE)
1795 # define UV_IF_NAMESIZE (IF_NAMESIZE + 1)
1796 #elif defined(IFNAMSIZ)
1797 # define UV_IF_NAMESIZE (IFNAMSIZ + 1)
1798 #else
1799 # define UV_IF_NAMESIZE (16 + 1)
1800 #endif
1801 
1802 UV_EXTERN int uv_if_indextoname(unsigned int ifindex,
1803                                 char* buffer,
1804                                 size_t* size);
1805 UV_EXTERN int uv_if_indextoiid(unsigned int ifindex,
1806                                char* buffer,
1807                                size_t* size);
1808 
1809 UV_EXTERN int uv_exepath(char* buffer, size_t* size);
1810 
1811 UV_EXTERN int uv_cwd(char* buffer, size_t* size);
1812 
1813 UV_EXTERN int uv_chdir(const char* dir);
1814 
1815 UV_EXTERN uint64_t uv_get_free_memory(void);
1816 UV_EXTERN uint64_t uv_get_total_memory(void);
1817 UV_EXTERN uint64_t uv_get_constrained_memory(void);
1818 UV_EXTERN uint64_t uv_get_available_memory(void);
1819 
1820 UV_EXTERN int uv_clock_gettime(uv_clock_id clock_id, uv_timespec64_t* ts);
1821 UV_EXTERN uint64_t uv_hrtime(void);
1822 UV_EXTERN void uv_sleep(unsigned int msec);
1823 
1824 UV_EXTERN void uv_disable_stdio_inheritance(void);
1825 
1826 UV_EXTERN int uv_dlopen(const char* filename, uv_lib_t* lib);
1827 UV_EXTERN void uv_dlclose(uv_lib_t* lib);
1828 UV_EXTERN int uv_dlsym(uv_lib_t* lib, const char* name, void** ptr);
1829 UV_EXTERN const char* uv_dlerror(const uv_lib_t* lib);
1830 
1831 UV_EXTERN int uv_mutex_init(uv_mutex_t* handle);
1832 UV_EXTERN int uv_mutex_init_recursive(uv_mutex_t* handle);
1833 UV_EXTERN void uv_mutex_destroy(uv_mutex_t* handle);
1834 UV_EXTERN void uv_mutex_lock(uv_mutex_t* handle);
1835 UV_EXTERN int uv_mutex_trylock(uv_mutex_t* handle);
1836 UV_EXTERN void uv_mutex_unlock(uv_mutex_t* handle);
1837 
1838 UV_EXTERN int uv_rwlock_init(uv_rwlock_t* rwlock);
1839 UV_EXTERN void uv_rwlock_destroy(uv_rwlock_t* rwlock);
1840 UV_EXTERN void uv_rwlock_rdlock(uv_rwlock_t* rwlock);
1841 UV_EXTERN int uv_rwlock_tryrdlock(uv_rwlock_t* rwlock);
1842 UV_EXTERN void uv_rwlock_rdunlock(uv_rwlock_t* rwlock);
1843 UV_EXTERN void uv_rwlock_wrlock(uv_rwlock_t* rwlock);
1844 UV_EXTERN int uv_rwlock_trywrlock(uv_rwlock_t* rwlock);
1845 UV_EXTERN void uv_rwlock_wrunlock(uv_rwlock_t* rwlock);
1846 
1847 UV_EXTERN int uv_sem_init(uv_sem_t* sem, unsigned int value);
1848 UV_EXTERN void uv_sem_destroy(uv_sem_t* sem);
1849 UV_EXTERN void uv_sem_post(uv_sem_t* sem);
1850 UV_EXTERN void uv_sem_wait(uv_sem_t* sem);
1851 UV_EXTERN int uv_sem_trywait(uv_sem_t* sem);
1852 
1853 UV_EXTERN int uv_cond_init(uv_cond_t* cond);
1854 UV_EXTERN void uv_cond_destroy(uv_cond_t* cond);
1855 UV_EXTERN void uv_cond_signal(uv_cond_t* cond);
1856 UV_EXTERN void uv_cond_broadcast(uv_cond_t* cond);
1857 
1858 UV_EXTERN int uv_barrier_init(uv_barrier_t* barrier, unsigned int count);
1859 UV_EXTERN void uv_barrier_destroy(uv_barrier_t* barrier);
1860 UV_EXTERN int uv_barrier_wait(uv_barrier_t* barrier);
1861 
1862 UV_EXTERN void uv_cond_wait(uv_cond_t* cond, uv_mutex_t* mutex);
1863 UV_EXTERN int uv_cond_timedwait(uv_cond_t* cond,
1864                                 uv_mutex_t* mutex,
1865                                 uint64_t timeout);
1866 
1867 UV_EXTERN void uv_once(uv_once_t* guard, void (*callback)(void));
1868 
1869 UV_EXTERN int uv_key_create(uv_key_t* key);
1870 UV_EXTERN void uv_key_delete(uv_key_t* key);
1871 UV_EXTERN void* uv_key_get(uv_key_t* key);
1872 UV_EXTERN void uv_key_set(uv_key_t* key, void* value);
1873 
1874 UV_EXTERN int uv_gettimeofday(uv_timeval64_t* tv);
1875 
1876 typedef void (*uv_thread_cb)(void* arg);
1877 
1878 UV_EXTERN int uv_thread_create(uv_thread_t* tid, uv_thread_cb entry, void* arg);
1879 UV_EXTERN int uv_thread_detach(uv_thread_t* tid);
1880 
1881 typedef enum {
1882   UV_THREAD_NO_FLAGS = 0x00,
1883   UV_THREAD_HAS_STACK_SIZE = 0x01
1884 } uv_thread_create_flags;
1885 
1886 struct uv_thread_options_s {
1887   unsigned int flags;
1888   size_t stack_size;
1889   /* More fields may be added at any time. */
1890 };
1891 
1892 typedef struct uv_thread_options_s uv_thread_options_t;
1893 
1894 UV_EXTERN int uv_thread_create_ex(uv_thread_t* tid,
1895                                   const uv_thread_options_t* params,
1896                                   uv_thread_cb entry,
1897                                   void* arg);
1898 UV_EXTERN int uv_thread_setaffinity(uv_thread_t* tid,
1899                                     char* cpumask,
1900                                     char* oldmask,
1901                                     size_t mask_size);
1902 UV_EXTERN int uv_thread_getaffinity(uv_thread_t* tid,
1903                                     char* cpumask,
1904                                     size_t mask_size);
1905 UV_EXTERN int uv_thread_getcpu(void);
1906 UV_EXTERN uv_thread_t uv_thread_self(void);
1907 UV_EXTERN int uv_thread_join(uv_thread_t *tid);
1908 UV_EXTERN int uv_thread_equal(const uv_thread_t* t1, const uv_thread_t* t2);
1909 UV_EXTERN int uv_thread_setname(const char* name);
1910 UV_EXTERN int uv_thread_getname(uv_thread_t* tid, char* name, size_t size);
1911 
1912 
1913 /* The presence of these unions force similar struct layout. */
1914 #define XX(_, name) uv_ ## name ## _t name;
1915 union uv_any_handle {
1916   UV_HANDLE_TYPE_MAP(XX)
1917 };
1918 
1919 union uv_any_req {
1920   UV_REQ_TYPE_MAP(XX)
1921 };
1922 #undef XX
1923 
1924 
1925 struct uv_loop_s {
1926   /* User data - use this for whatever. */
1927   void* data;
1928   /* Loop reference counting. */
1929   unsigned int active_handles;
1930   struct uv__queue handle_queue;
1931   union {
1932     void* unused;
1933     unsigned int count;
1934   } active_reqs;
1935   /* Internal storage for future extensions. */
1936   void* internal_fields;
1937   /* Internal flag to signal loop stop. */
1938   unsigned int stop_flag;
1939   UV_LOOP_PRIVATE_FIELDS
1940 };
1941 
1942 UV_EXTERN void* uv_loop_get_data(const uv_loop_t*);
1943 UV_EXTERN void uv_loop_set_data(uv_loop_t*, void* data);
1944 
1945 /* Unicode utilities needed for dealing with Windows. */
1946 UV_EXTERN size_t uv_utf16_length_as_wtf8(const uint16_t* utf16,
1947                                          ssize_t utf16_len);
1948 UV_EXTERN int uv_utf16_to_wtf8(const uint16_t* utf16,
1949                                ssize_t utf16_len,
1950                                char** wtf8_ptr,
1951                                size_t* wtf8_len_ptr);
1952 UV_EXTERN ssize_t uv_wtf8_length_as_utf16(const char* wtf8);
1953 UV_EXTERN void uv_wtf8_to_utf16(const char* wtf8,
1954                                 uint16_t* utf16,
1955                                 size_t utf16_len);
1956 
1957 /* Don't export the private CPP symbols. */
1958 #undef UV_HANDLE_TYPE_PRIVATE
1959 #undef UV_REQ_TYPE_PRIVATE
1960 #undef UV_REQ_PRIVATE_FIELDS
1961 #undef UV_STREAM_PRIVATE_FIELDS
1962 #undef UV_TCP_PRIVATE_FIELDS
1963 #undef UV_PREPARE_PRIVATE_FIELDS
1964 #undef UV_CHECK_PRIVATE_FIELDS
1965 #undef UV_IDLE_PRIVATE_FIELDS
1966 #undef UV_ASYNC_PRIVATE_FIELDS
1967 #undef UV_TIMER_PRIVATE_FIELDS
1968 #undef UV_GETADDRINFO_PRIVATE_FIELDS
1969 #undef UV_GETNAMEINFO_PRIVATE_FIELDS
1970 #undef UV_FS_REQ_PRIVATE_FIELDS
1971 #undef UV_WORK_PRIVATE_FIELDS
1972 #undef UV_FS_EVENT_PRIVATE_FIELDS
1973 #undef UV_SIGNAL_PRIVATE_FIELDS
1974 #undef UV_LOOP_PRIVATE_FIELDS
1975 #undef UV_LOOP_PRIVATE_PLATFORM_FIELDS
1976 #undef UV__ERR
1977 
1978 #ifdef __cplusplus
1979 }
1980 #endif
1981 #endif /* UV_H */
1982