blob: 823f68266b07336fe9b2803509c269a10b7eccd7 [file] [log] [blame]
* Copyright 2015 gRPC authors.
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* See the License for the specific language governing permissions and
* limitations under the License.
#include <grpc/support/port_platform.h>
#include <poll.h>
#include "src/core/lib/debug/trace.h"
#include "src/core/lib/gprpp/global_config.h"
#include "src/core/lib/iomgr/exec_ctx.h"
#include "src/core/lib/iomgr/pollset.h"
#include "src/core/lib/iomgr/pollset_set.h"
#include "src/core/lib/iomgr/wakeup_fd_posix.h"
extern grpc_core::DebugOnlyTraceFlag grpc_fd_trace; /* Disabled by default */
extern grpc_core::DebugOnlyTraceFlag
grpc_polling_trace; /* Disabled by default */
#define GRPC_FD_TRACE(format, ...) \
if (GRPC_TRACE_FLAG_ENABLED(grpc_fd_trace)) { \
gpr_log(GPR_INFO, "(fd-trace) " format, __VA_ARGS__); \
typedef struct grpc_fd grpc_fd;
typedef struct grpc_event_engine_vtable {
size_t pollset_size;
bool can_track_err;
bool run_in_background;
grpc_fd* (*fd_create)(int fd, const char* name, bool track_err);
int (*fd_wrapped_fd)(grpc_fd* fd);
void (*fd_orphan)(grpc_fd* fd, grpc_closure* on_done, int* release_fd,
const char* reason);
void (*fd_shutdown)(grpc_fd* fd, grpc_error_handle why);
void (*fd_notify_on_read)(grpc_fd* fd, grpc_closure* closure);
void (*fd_notify_on_write)(grpc_fd* fd, grpc_closure* closure);
void (*fd_notify_on_error)(grpc_fd* fd, grpc_closure* closure);
void (*fd_set_readable)(grpc_fd* fd);
void (*fd_set_writable)(grpc_fd* fd);
void (*fd_set_error)(grpc_fd* fd);
bool (*fd_is_shutdown)(grpc_fd* fd);
void (*pollset_init)(grpc_pollset* pollset, gpr_mu** mu);
void (*pollset_shutdown)(grpc_pollset* pollset, grpc_closure* closure);
void (*pollset_destroy)(grpc_pollset* pollset);
grpc_error_handle (*pollset_work)(grpc_pollset* pollset,
grpc_pollset_worker** worker,
grpc_core::Timestamp deadline);
grpc_error_handle (*pollset_kick)(grpc_pollset* pollset,
grpc_pollset_worker* specific_worker);
void (*pollset_add_fd)(grpc_pollset* pollset, struct grpc_fd* fd);
grpc_pollset_set* (*pollset_set_create)(void);
void (*pollset_set_destroy)(grpc_pollset_set* pollset_set);
void (*pollset_set_add_pollset)(grpc_pollset_set* pollset_set,
grpc_pollset* pollset);
void (*pollset_set_del_pollset)(grpc_pollset_set* pollset_set,
grpc_pollset* pollset);
void (*pollset_set_add_pollset_set)(grpc_pollset_set* bag,
grpc_pollset_set* item);
void (*pollset_set_del_pollset_set)(grpc_pollset_set* bag,
grpc_pollset_set* item);
void (*pollset_set_add_fd)(grpc_pollset_set* pollset_set, grpc_fd* fd);
void (*pollset_set_del_fd)(grpc_pollset_set* pollset_set, grpc_fd* fd);
bool (*is_any_background_poller_thread)(void);
void (*shutdown_background_closure)(void);
void (*shutdown_engine)(void);
bool (*add_closure_to_background_poller)(grpc_closure* closure,
grpc_error_handle error);
} grpc_event_engine_vtable;
/* register a new event engine factory */
void grpc_register_event_engine_factory(
const char* name, const grpc_event_engine_vtable* (*factory)(bool),
bool add_at_head);
void grpc_event_engine_init(void);
void grpc_event_engine_shutdown(void);
/* Return the name of the poll strategy */
const char* grpc_get_poll_strategy_name();
/* Returns true if polling engine can track errors separately, false otherwise.
* If this is true, fd can be created with track_err set. After this, error
* events will be reported using fd_notify_on_error. If it is not set, errors
* will continue to be reported through fd_notify_on_read and
* fd_notify_on_write.
bool grpc_event_engine_can_track_errors();
/* Returns true if polling engine runs in the background, false otherwise.
* Currently only 'epollbg' runs in the background.
bool grpc_event_engine_run_in_background();
/* Create a wrapped file descriptor.
Requires fd is a non-blocking file descriptor.
\a track_err if true means that error events would be tracked separately
using grpc_fd_notify_on_error. Currently, valid only for linux systems.
This takes ownership of closing fd. */
grpc_fd* grpc_fd_create(int fd, const char* name, bool track_err);
/* Return the wrapped fd, or -1 if it has been released or closed. */
int grpc_fd_wrapped_fd(grpc_fd* fd);
/* Releases fd to be asynchronously destroyed.
on_done is called when the underlying file descriptor is definitely close()d.
If on_done is NULL, no callback will be made.
If release_fd is not NULL, it's set to fd and fd will not be closed.
Requires: *fd initialized; no outstanding notify_on_read or
MUST NOT be called with a pollset lock taken */
void grpc_fd_orphan(grpc_fd* fd, grpc_closure* on_done, int* release_fd,
const char* reason);
/* Has grpc_fd_shutdown been called on an fd? */
bool grpc_fd_is_shutdown(grpc_fd* fd);
/* Cause any current and future callbacks to fail. */
void grpc_fd_shutdown(grpc_fd* fd, grpc_error_handle why);
/* Register read interest, causing read_cb to be called once when fd becomes
readable, on deadline specified by deadline, or on shutdown triggered by
read_cb will be called with read_cb_arg when *fd becomes readable.
read_cb is Called with status of GRPC_CALLBACK_SUCCESS if readable,
GRPC_CALLBACK_TIMED_OUT if the call timed out,
and CANCELLED if the call was cancelled.
Requires:This method must not be called before the read_cb for any previous
call runs. Edge triggered events are used whenever they are supported by the
underlying platform. This means that users must drain fd in read_cb before
calling notify_on_read again. Users are also expected to handle spurious
events, i.e read_cb is called while nothing can be readable from fd */
void grpc_fd_notify_on_read(grpc_fd* fd, grpc_closure* closure);
/* Exactly the same semantics as above, except based on writable events. */
void grpc_fd_notify_on_write(grpc_fd* fd, grpc_closure* closure);
/* Exactly the same semantics as above, except based on error events. track_err
* needs to have been set on grpc_fd_create */
void grpc_fd_notify_on_error(grpc_fd* fd, grpc_closure* closure);
/* Forcibly set the fd to be readable, resulting in the closure registered with
* grpc_fd_notify_on_read being invoked.
void grpc_fd_set_readable(grpc_fd* fd);
/* Forcibly set the fd to be writable, resulting in the closure registered with
* grpc_fd_notify_on_write being invoked.
void grpc_fd_set_writable(grpc_fd* fd);
/* Forcibly set the fd to have errored, resulting in the closure registered with
* grpc_fd_notify_on_error being invoked.
void grpc_fd_set_error(grpc_fd* fd);
/* pollset_posix functions */
/* Add an fd to a pollset */
void grpc_pollset_add_fd(grpc_pollset* pollset, struct grpc_fd* fd);
/* pollset_set_posix functions */
void grpc_pollset_set_add_fd(grpc_pollset_set* pollset_set, grpc_fd* fd);
void grpc_pollset_set_del_fd(grpc_pollset_set* pollset_set, grpc_fd* fd);
/* Returns true if the caller is a worker thread for any background poller. */
bool grpc_is_any_background_poller_thread();
/* Returns true if the closure is registered into the background poller. Note
* that the closure may or may not run yet when this function returns, and the
* closure should not be blocking or long-running. */
bool grpc_add_closure_to_background_poller(grpc_closure* closure,
grpc_error_handle error);
/* Shut down all the closures registered in the background poller. */
void grpc_shutdown_background_closure();
/* override to allow tests to hook poll() usage */
typedef int (*grpc_poll_function_type)(struct pollfd*, nfds_t, int);
extern grpc_poll_function_type grpc_poll_function;