/*
* This file is part of the Sofia-SIP package
*
* Copyright (C) 2005 Nokia Corporation.
*
* Contact: Pekka Pessi <pekka.pessi@nokia.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public License
* as published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*
*/
/**@ingroup su_wait
* @CFILE su_root.c
* OS-independent synchronization interface.
* @internal
*
* @author Pekka Pessi <Pekka.Pessi@nokia.com>
*
* @date Created: Tue Sep 14 15:51:04 1999 ppessi
*/
#include "config.h"
#include <stdlib.h>
#include <assert.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include "sofia-sip/su.h"
#if SU_HAVE_PTHREADS
#include <pthread.h>
#endif
struct su_root_s;
typedef struct su_cloned_s {
struct su_root_s *sc_root;
int *sc_wait;
#if SU_HAVE_PTHREADS
pthread_t sc_tid;
pthread_mutex_t sc_pause[1];
pthread_cond_t sc_resume[1];
int sc_paused;
#endif
} su_cloned_t;
#define SU_ROOT_MAGIC_T struct su_root_magic_s
#define SU_WAKEUP_ARG_T struct su_wakeup_arg_s
#define SU_TIMER_ARG_T struct su_timer_arg_s
#define SU_CLONE_T su_msg_t
#define SU_MSG_ARG_T struct su_cloned_s
#include "su_port.h"
#include "sofia-sip/su_alloc.h"
/**@ingroup su_wait
*
* @page su_root_t Tasks and root objects
*
* A task is the basic execution unit for the Sofia event-driven programming
* model. According to the model, the program can ask that the event loop
* invokes a callback function when a certain event occurs. Such events
* include @ref su_root_register "I/O activity", @ref su_timer_t "timers" or
* a @ref su_msg_t "message" from other task. The event loop is run with
* function su_root_run() or su_root_step().
*
* Root object gives access to the task control. The root object represents
* the task to the code running within task. Through the root, the task code
* can access its context object (magic) and thread-synchronization features
* like wait objects, timers, and messages.
*
* When a message is sent between tasks, a task reference #su_task_r is used
* to reprent the task address. Reference counting is used to make sure that
* the task references stay valid.
*
* The public API contains following functions:
* - su_root_create() [Do not call from cloned task]
* - su_root_destroy() [Do not call from cloned task]
* - su_root_magic()
* - su_root_register()
* - su_root_deregister()
* - su_root_unregister()
* - su_root_threading()
* - su_root_run() [Do not call from cloned task]
* - su_root_break() [Do not call from cloned task]
* - su_root_step() [Do not call from cloned task]
* - su_root_task()
*
* New tasks can be created via su_clone_start() function.
*/
/**@ingroup su_wait
*
* @page su_root_register Registering Wait Objects
*
* When application expects I/O events, it can create a wait object and
* register it, a callback function and a context pointer to the #su_root_t
* object using the su_root_register() function. Whenever the wait object
* receives an event, the registered @link ::su_wakeup_f callback function
* @endlink is invoked.
*
* When successful, the su_root_register() returns an small non-negative
* integer representing the registration. The registration can be
* manipulated with su_root_eventmask() function, for instance, when sending
* through a socket block, the application can add SU_WAIT_OUT event to the
* mask.
*
* The registration can be removed using su_root_deregister() function.
*/
/**@ingroup su_wait
*
* Contains hint of number of sockets supported by su_root_t */
int su_root_size_hint = 64;
/* =========================================================================
* Tasks
*/
su_task_r const su_task_null = SU_TASK_R_INIT;
#define SU_TASK_ZAP(t, f) \
while (t->sut_port) { \
SU_PORT_DECREF(t->sut_port, f); t->sut_port = NULL; break; }
#define SU_TASK_ZAPP(t, f) \
do { if (t->sut_port) { \
SU_PORT_DECREF(t->sut_port, f); t->sut_port = NULL; } \
t->sut_root = NULL; } while(0)
/**
* Initialize a task handle with su_task_null.
*
* @param task task handle
*
* @return A reference to the initialized task handle.
*/
_su_task_r su_task_init(su_task_r task)
{
assert(task);
memset(task, 0, sizeof(task));
return task;
}
/**
* Destroy a task handle
*
* @param task task handle
*/
void su_task_deinit(su_task_r task)
{
assert(task);
SU_TASK_ZAP(task, su_task_deinit);
task->sut_root = NULL;
}
/**
* Create a new task handle.
*
* @param task task reference
* @param root pointer to root object
* @param port pointer to port object
*
* @return New task handle.
*/
_su_task_r su_task_new(su_task_r task, su_root_t *root, su_port_t *port)
{
assert(task);
task->sut_root = root;
if ((task->sut_port = port)) {
SU_PORT_INCREF(port, su_task_new);
}
return task;
}
/**
* Duplicates a task handle.
*
* @param dst destination task reference
* @param src source task reference
*/
void su_task_copy(su_task_r dst, su_task_r const src)
{
su_port_t *port;
assert(src); assert(dst);
SU_TASK_ZAP(dst, su_task_copy);
port = src->sut_port;
if (port) {
SU_PORT_INCREF(port, su_task_copy);
}
dst[0] = src[0];
}
#define SU_TASK_COPY(d, s, by) (void)((d)[0]=(s)[0], \
(s)->sut_port?(void)SU_PORT_INCREF(s->sut_port, by):(void)0)
/**
* Moves a task handle.
*
* @param dst destination task reference
* @param src source task reference
*/
void su_task_move(su_task_r dst, su_task_r src)
{
SU_TASK_ZAP(dst, su_task_move);
dst[0] = src[0];
src->sut_port = 0;
src->sut_root = 0;
}
/**
* Compare two tasks with each other.
*
* @param a First task
* @param b Second task
*
* @retval negative number, if a < b
* @retval positive number, if a > b
* @retval 0, if a == b.
*/
int su_task_cmp(su_task_r const a, su_task_r const b)
{
intptr_t retval = a->sut_port - b->sut_port;
retval = retval ? retval : (char *)a->sut_root - (char *)b->sut_root;
if (sizeof(retval) != sizeof(int)) {
if (retval < 0)
retval = -1;
else if (retval > 0)
retval = 1;
}
return (int)retval;
}
/**
* Tests if a task is running.
*
* @param task task handle
*
* @retval true (nonzero) if task is not stopped,
* @retval zero if it is null or stopped.
*/
int su_task_is_running(su_task_r const task)
{
return
task &&
task->sut_port &&
task->sut_root;
}
/** @internal
* Attach a root object to the task handle.
*
* @param self task handle
* @param root pointer to the root object
*
* @retval 0 if successful,
* @retval -1 otherwise.
*/
int su_task_attach(su_task_r self, su_root_t *root)
{
if (self->sut_port) {
self->sut_root = root;
return 0;
}
else
return -1;
}
/**
* Get root pointer attached to a task handle.
*
* @param self task handle
*
* @return
* A pointer to root object attached to the task handle, or NULL if no root
* object has been attached.
*/
su_root_t *su_task_root(su_task_r const self)
{
if (self->sut_port) return self->sut_root; else return NULL;
}
#if 0
/** @internal
* Detach a root pointer from task handle.
* @bug Not used anymore.
*/
int su_task_detach(su_task_r self)
{
self->sut_root = NULL;
return 0;
}
#endif
/**
* Return the timer list associated with given task.
*
* @param task task handle
*
* @return A timer list of the task. If there are no timers, it returns
* NULL.
*/
su_timer_t **su_task_timers(su_task_r const task)
{
return task ? su_port_timers(task->sut_port) : NULL;
}
#if SU_HAVE_PTHREADS
struct su_task_execute
{
pthread_mutex_t mutex[1];
pthread_cond_t cond[1];
int (*function)(void *);
void *arg;
int value;
};
static void _su_task_execute(su_root_magic_t *m,
su_msg_r msg,
su_msg_arg_t *a)
{
struct su_task_execute *frame = *(struct su_task_execute **)a;
pthread_mutex_lock(frame->mutex);
frame->value = frame->function(frame->arg);
frame->function = NULL; /* Mark as completed */
pthread_cond_signal(frame->cond);
pthread_mutex_unlock(frame->mutex);
}
#endif
/** Execute by task thread
*
* @retval 0 if successful
* @retval -1 upon an error
*/
int su_task_execute(su_task_r const task,
int (*function)(void *), void *arg,
int *return_value)
{
if (function == NULL)
return (errno = EFAULT), -1;
if (!su_port_own_thread(task->sut_port)) {
#if SU_HAVE_PTHREADS
int success;
su_msg_r m = SU_MSG_R_INIT;
struct su_task_execute frame = {
{ PTHREAD_MUTEX_INITIALIZER },
{ PTHREAD_COND_INITIALIZER },
function, arg, 0
};
if (su_msg_create(m, task, su_task_null,
_su_task_execute, (sizeof &frame)) < 0)
return -1;
*(struct su_task_execute **)su_msg_data(m) = &frame;
pthread_mutex_lock(frame.mutex);
success = su_msg_send(m);
if (success == 0)
while (frame.function)
pthread_cond_wait(frame.cond, frame.mutex);
else
su_msg_destroy(m);
pthread_mutex_unlock(frame.mutex);
pthread_mutex_destroy(frame.mutex);
pthread_cond_destroy(frame.cond);
if (return_value)
*return_value = frame.value;
return success;
#else
return (errno = ENOSYS), -1;
#endif
}
else {
int value = function(arg);
if (return_value)
*return_value = value;
return 0;
}
}
_su_task_r su_task_new(su_task_r task, su_root_t *root, su_port_t *port);
int su_task_attach(su_task_r self, su_root_t *root);
int su_task_detach(su_task_r self);
int su_timer_reset_all(su_timer_t **t0, su_task_r);
/**@ingroup su_wait
*
* @page su_clone_t Clone Objects
*
* The process may be divided into many tasks via cloning. Several tasks may
* run in context of one thread, or each task may be run by its own thread.
* However, only a single thread can execute code within a task. There can
* be a 1-to-N mapping from thread to tasks. Thus, software using tasks can
* be executed by multiple threads in a multithreaded environment and by a
* single thread in a singlethreaded environment.
*
* The clones are useful for handling tasks that can be executed by a
* separate threads, but which do not block excessively. When threads are
* not available or they are not needed, clones can also be run in a
* single-threaded mode. Running in single-threaded mode is especially
* useful while debugging.
*
* A clone task is created with function su_clone_start(). Each clone has
* its own root object (su_root_t), which holds a context pointer
* (su_root_magic_t *). The context object can be different from that of
* parent task.
*
* When a clone is started, the clone initialization function is called. The
* initialization function should do whatever initialization there is to be
* performed, register I/O events and timers, and then return. If the
* initialization is successful, the clone task reverts to run the event
* loop and invoking the event callbacks until its parent stops it by
* calling su_clone_wait() which invokes the deinit function. The clone task
* is destroyed when the deinit function returns.
*
* The public API consists of following functions:
* - su_clone_start()
* - su_clone_task()
* - su_clone_wait()
* - su_clone_forget()
*
* @note
* There is only one event loop for each thread which can be shared by
* multiple clone tasks. Therefore, the clone tasks can not explicitly run
* or step the event loop, but they are limited to event callbacks. A clone
* task may not call su_root_break(), su_root_run() or su_root_step().
*/
static void su_root_deinit(su_root_t *self);
/* Note that is *not* necessary same as su_root_t,
* as su_root_t can be extended */
#define sur_port sur_task->sut_port
#define sur_root sur_task->sut_root
#define SU_ROOT_OWN_THREAD(r) (su_port_own_thread(r->sur_port))
/** Create a reactor object.
*
* Allocate and initialize the instance of su_root_t.
*
* @param magic pointer to user data
*
* @return A pointer to allocated su_root_t instance, NULL on error.
*/
su_root_t *su_root_create(su_root_magic_t *magic)
{
return su_root_create_with_port(magic, su_port_create());
}
/** Create a reactor object using given message port.
*
* Allocate and initialize the instance of su_root_t.
*
* @param magic pointer to user data
* @param port pointer to a message port
*
* @return A pointer to allocated su_root_t instance, NULL on error.
*/
su_root_t *su_root_create_with_port(su_root_magic_t *magic,
su_port_t *port)
{
su_root_t *self;
if (!port)
return NULL;
self = su_salloc(NULL, sizeof(struct su_root_s));
if (self) {
self->sur_magic = magic;
#if SU_HAVE_PTHREADS
self->sur_threading = SU_HAVE_PTHREADS;
#else
self->sur_threading = 0;
#endif
su_task_new(self->sur_task, self, port);
} else {
su_port_decref(port, "su_root_create");
}
return self;
}
/** Destroy a synchronization object.
*
* Stop and free an instance of su_root_t
*
* @param self pointer to a root object.
*/
void su_root_destroy(su_root_t *self)
{
if (self) {
assert(SU_ROOT_OWN_THREAD(self));
su_root_deinit(self);
su_free(NULL, self);
}
}
/** @internal Deinitialize a synchronization object.
*
* Deinitialize an instance of su_root_t
*
* @param self pointer to a root object.
*/
static void su_root_deinit(su_root_t *self)
{
self->sur_deiniting = 1;
if (self->sur_deinit) {
su_root_deinit_f deinit = self->sur_deinit;
su_root_magic_t *magic = self->sur_magic;
self->sur_deinit = NULL;
deinit(self, magic);
}
if (self->sur_port) {
int n_w = su_port_unregister_all(self->sur_port, self);
int n_t = su_timer_reset_all(su_task_timers(self->sur_task), self->sur_task);
if (n_w || n_t)
SU_DEBUG_1(("su_root_deinit: "
"%u registered waits, %u timers\n", n_w, n_t));
}
SU_TASK_ZAP(self->sur_parent, su_root_deinit);
SU_TASK_ZAP(self->sur_task, su_root_deinit);
}
/** Set the context pointer.
*
* Set the context pointer (magic) of a root object.
*
* @param self pointer to a root object
* @param magic pointer to user data
*
* @retval 0 when successful,
* @retval -1 upon error.
*/
int su_root_set_magic(su_root_t *self, su_root_magic_t *magic)
{
assert(SU_ROOT_OWN_THREAD(self));
if (self) {
self->sur_magic = magic;
}
return 0;
}
/** Set threading option.
*
* Controls whether su_clone_start() creates a new thread.
*
* @param self pointer to a root object
* @param enable if true, enable threading, if false, disable threading
*
* @return True if threading is enabled.
*/
int su_root_threading(su_root_t *self, int enable)
{
if (self) {
assert(SU_ROOT_OWN_THREAD(self));
#if SU_HAVE_PTHREADS
self->sur_threading = enable = enable != 0;
return enable;
#endif
}
return 0;
}
/** Get context pointer.
*
* The function su_root_magic() returns the user context pointer that was
* given input to su_root_create() or su_root_set_magic().
*
* @param self pointer to a root object
*
* @return A pointer to user data
*/
su_root_magic_t *su_root_magic(su_root_t *self)
{
return self ? self->sur_magic : NULL;
}
/** Get a GSource */
struct _GSource *su_root_gsource(su_root_t *self)
{
return self ? su_port_gsource(self->sur_port) : NULL;
}
/** Register a su_wait_t object.
*
* The function su_root_register() registers a su_wait_t object. The wait
* object, a callback function and a argument are stored to the root
* object. The callback function is called, when the wait object is
* signaled.
*
* Please note if identical wait objects are inserted, only first one is
* ever signalled.
*
* @param self pointer to root object
* @param wait pointer to wait object
* @param callback callback function pointer
* @param arg argument given to callback function when it is invoked
* @param priority relative priority of the wait object
* (0 is normal, 1 important, 2 realtime)
*
* @return Nonzero index of the wait object, or -1 upon an error.
*/
int su_root_register(su_root_t *self,
su_wait_t *wait,
su_wakeup_f callback,
su_wakeup_arg_t *arg,
int priority)
{
assert(self && self->sur_port);
if (!self || !self->sur_port)
return -1;
return su_port_register(self->sur_port, self, wait, callback, arg, priority);
}
/** Unregister a su_wait_t object.
*
* The function su_root_unregister() unregisters a su_wait_t object. The
* wait object, a callback function and a argument are removed from the
* root object.
*
* @param self pointer to root object
* @param wait pointer to wait object
* @param callback callback function pointer (may be NULL)
* @param arg argument given to callback function when it is invoked
* (may be NULL)
*
* @return Nonzero index of the wait object, or -1 upon an error.
*/
int su_root_unregister(su_root_t *self,
su_wait_t *wait,
su_wakeup_f callback, /* XXX - ignored */
su_wakeup_arg_t *arg)
{
assert(self && self->sur_port);
if (!self || !self->sur_port)
return -1;
return su_port_unregister(self->sur_port, self, wait, callback, arg);
}
/** Remove a su_wait_t registration.
*
* The function su_root_deregister() deregisters a su_wait_t object. The
* wait object, a callback function and a argument are removed from the
* root object. The wait object is destroyed.
*
* @param self pointer to root object
* @param i registration index
*
* @return Index of the wait object, or -1 upon an error.
*/
int su_root_deregister(su_root_t *self, int i)
{
if (i == 0 || i == -1)
return -1;
assert(self && self->sur_port);
if (!self || !self->sur_port)
return -1;
return su_port_deregister(self->sur_port, i);
}
/** Set mask for a registered event.
*
* The function su_root_eventmask() sets the mask describing events that can
* signal the registered callback.
*
* @param self pointer to root object
* @param index registration index
* @param socket socket
* @param events new event mask
*
* @retval 0 when successful,
* @retval -1 upon an error.
*/
int su_root_eventmask(su_root_t *self, int index, int socket, int events)
{
assert(self && self->sur_port);
if (!self || !self->sur_port)
return -1;
return su_port_eventmask(self->sur_port, index, socket, events);
}
/** Set multishot mode.
*
* The function su_root_multishot() enables, disables or queries the
* multishot mode for the root. The multishot mode determines how the events
* are scheduled by root. If multishot mode is enabled, root serves all the
* sockets that have received network events. If it is disables, only first
* socket event is served.
*
* @param self pointer to root object
* @param multishot multishot mode (0 => disables, 1 => enables, -1 => query)
*
* @retval 0 multishot mode is disabled
* @retval 1 multishot mode is enabled
* @retval -1 an error occurred
*/
int su_root_multishot(su_root_t *self, int multishot)
{
if (self && self->sur_port) {
return su_port_multishot(self->sur_port, multishot);
} else {
return (errno = EINVAL), -1;
}
}
/** Run event and message loop.
*
* The function su_root_run() runs the root main loop. The root loop waits
* for wait objects and the timers associated with the root object. When any
* wait object is signaled or timer is expired, it invokes the callbacks,
* and returns waiting.
*
* This function returns when su_root_break() is called from a callback.
*
* @param self pointer to root object
*
*/
void su_root_run(su_root_t *self)
{
assert(self && self->sur_port);
if (self && self->sur_port)
su_port_run(self->sur_port);
}
/** Terminate event loop.
*
* The function su_root_break() is used to terminate execution of
* su_root_run(). It can be called from a callback function.
*
* @param self pointer to root object
*/
void su_root_break(su_root_t *self)
{
assert(self && self->sur_port);
if (self && self->sur_port)
su_port_break(self->sur_port);
}
/** Process events, timers and messages.
*
* The function su_root_step() waits for wait objects and the timers
* associated with the root object. When any wait object is signaled or
* timer is expired, it invokes the callbacks.
*
* This function returns when a callback has been invoked or tout
* milliseconds is elapsed.
*
* @param self pointer to root object
* @param tout timeout in milliseconds
*
* @return Milliseconds to the next invocation of timer, or SU_WAIT_FOREVER
* if there are no active timers.
*/
su_duration_t su_root_step(su_root_t *self, su_duration_t tout)
{
assert(self && self->sur_port);
return su_port_step(self->sur_port, tout);
}
/**Run event and message loop for given duration.
*
* The function su_root_sleep() runs event loop for @a duration milliseconds.
* The event loop waits for wait objects and the timers associated with the
* @a root object. When any wait object is signaled, timer is expired, or
* message is received, it invokes the callbacks and returns waiting.
*
* @param self pointer to root object
* @param duration milliseconds to run event loop
*/
su_duration_t su_root_sleep(su_root_t *self, su_duration_t duration)
{
su_duration_t retval, accrued = 0;
su_time_t started = su_now();
assert(self && self->sur_port);
do {
retval = su_port_step(self->sur_port, duration - accrued);
accrued = su_duration(su_now(), started);
} while (accrued < duration);
return retval;
}
/** Check wait events in callbacks that take lots of time
*
* This function does a 0 timeout poll() and runs wait objects
*
* @param self pointer to root object
*/
int su_root_yield(su_root_t *self)
{
if (self && self->sur_task[0].sut_port) {
su_port_t *port = self->sur_task[0].sut_port;
/* Make sure we have su_port_yield extension */
if (port->sup_vtable->su_vtable_size >=
offsetof(su_port_vtable_t, su_port_yield)
&& port->sup_vtable->su_port_yield)
return port->sup_vtable->su_port_yield(port);
}
errno = EINVAL;
return -1;
}
/** Get task reference.
*
* The function su_root_task() is used to retrieve the task reference
* (PId) related with the root object.
*
* @param self a pointer to a root object
*
* @return The function su_root_task() returns a reference to the task
* object.
*/
_su_task_r su_root_task(su_root_t const *self)
{
if (self)
return self->sur_task;
else
return su_task_null;
}
/** Get parent task reference.
*
* The function su_root_parent() is used to retrieve the task reference
* (PId) of the parent task.
*
* @param self a pointer to a root object
*
* @return The function su_root_parent() returns a reference to the parent
* task object.
*/
_su_task_r su_root_parent(su_root_t const *self)
{
if (self)
return self->sur_parent;
else
return su_task_null;
}
/** Add a pre-poll callback. */
int su_root_add_prepoll(su_root_t *root,
su_prepoll_f *callback,
su_prepoll_magic_t *magic)
{
if (root == NULL || root->sur_port == NULL)
return -1;
return su_port_add_prepoll(root->sur_port, root, callback, magic);
}
/** Remove a pre-poll callback */
int su_root_remove_prepoll(su_root_t *root)
{
if (root == NULL || root->sur_port == NULL)
return -1;
return su_port_remove_prepoll(root->sur_port, root);
}
/* ========================================================================
* su_clone_t
*/
/* - su_clone_forget() */
#if SU_HAVE_PTHREADS
struct clone_args
{
su_root_t * self;
su_root_init_f init;
su_root_deinit_f deinit;
pthread_mutex_t mutex;
pthread_cond_t cv;
int retval;
su_msg_r clone;
su_root_t const *parent;
};
static void su_clone_report2(su_root_magic_t *m,
su_msg_r msg,
su_cloned_t *sc);
static void su_clone_signal_parent(void *varg)
{
struct clone_args *arg = (struct clone_args *)varg;
pthread_mutex_lock(&arg->mutex);
pthread_cond_signal(&arg->cv);
pthread_mutex_unlock(&arg->mutex);
}
/** Message function for clone message.
*
* This calls the clone task deinitialization function, which should make
* sure that no more messages are sent by clone task.
*
* @sa su_clone_wait()
*/
static void su_clone_break(su_root_magic_t *m,
su_msg_r msg,
su_cloned_t *sc)
{
su_root_t *root = sc->sc_root;
root->sur_deiniting = 1;
if (root->sur_deinit) {
su_root_deinit_f deinit = root->sur_deinit;
su_root_magic_t *magic = root->sur_magic;
root->sur_deinit = NULL;
deinit(root, magic);
}
}
/** Delivery report function for clone message.
*
* This is executed by parent task. This is the last message sent by clone task.
*/
static void su_clone_report(su_root_magic_t *m,
su_msg_r msg,
su_cloned_t *sc)
{
su_msg_report(msg, su_clone_report2);
}
/** Back delivery report function for clone message.
*
* This is executed by clone task. It completes the three way handshake and
* it is used to signal clone that it can destroy its port.
*/
static void su_clone_report2(su_root_magic_t *m,
su_msg_r msg,
su_cloned_t *sc)
{
su_root_break(sc->sc_root);
if (sc->sc_wait)
*sc->sc_wait = 0;
}
static void *su_clone_main(void *varg)
{
struct clone_args *arg = (struct clone_args *)varg;
su_root_t *self = arg->self;
su_port_t *port;
su_cloned_t *sc;
pthread_cleanup_push(su_clone_signal_parent, varg);
#if SU_HAVE_WINSOCK
su_init();
#endif
port = su_port_create();
if (!port)
pthread_exit(NULL);
su_port_threadsafe(port);
SU_PORT_INCREF(port, su_clone_main);
/* Change task ownership */
SU_PORT_INCREF(self->sur_task->sut_port = port, su_clone_main);
self->sur_task->sut_root = self;
if (su_msg_create(arg->clone,
self->sur_task, su_root_task(arg->parent),
su_clone_break, sizeof(self)) != 0) {
su_port_decref(self->sur_port, "su_clone_main");
self->sur_port = NULL;
pthread_exit(NULL);
}
su_msg_report(arg->clone, su_clone_report);
sc = su_msg_data(arg->clone);
sc->sc_root = self;
sc->sc_tid = pthread_self();
pthread_mutex_init(sc->sc_pause, NULL);
pthread_cond_init(sc->sc_resume, NULL);
pthread_mutex_lock(sc->sc_pause);
if (arg->init && arg->init(self, self->sur_magic) != 0) {
if (arg->deinit)
arg->deinit(self, self->sur_magic);
su_msg_destroy(arg->clone);
su_port_decref(self->sur_port, "su_clone_main");
self->sur_port = NULL;
pthread_exit(NULL);
}
arg->retval = 0;
pthread_cleanup_pop(1); /* signal change of ownership */
su_root_run(self); /* Do the work */
su_root_destroy(self); /* Cleanup root */
SU_PORT_ZAPREF(port, su_clone_main);
#if SU_HAVE_WINSOCK
su_deinit();
#endif
return NULL;
}
#endif
static void su_clone_xyzzy(su_root_magic_t *m,
su_msg_r msg,
su_cloned_t *sc)
{
su_root_destroy(sc->sc_root);
if (sc->sc_wait)
*sc->sc_wait = 0;
}
/** Start a clone task.
*
* The function su_clone_start() allocates and initializes a sub-task.
* Depending on the settings, a separate thread may be created to execute
* the sub-task. The sub-task is represented by clone handle to the rest of
* the application. The function su_clone_start() returns the clone handle
* in @a return_clone. The clone handle is used to communicate with the
* newly created clone task using messages.
*
* A new #su_root_t object is created for the sub-task with the @a magic as
* the root context pointer. Because the sub-task may or may not have its
* own thread, all its activity must be scheduled via this root object. In
* other words, the sub-task can be schedule
* -# I/O events with su_root_register()
* -# timers with su_timer_set(), su_timer_set_at() or su_timer_run()
* -# messages with su_msg_send().
*
* Messages can also be used to pass information between tasks or threads.
*
* In multi-threaded implementation, su_clone_start() launches a new thread,
* and the initialization routine is executed by this newly created thread.
* The calling thread blocks until the initialization routine completes. If
* the initialization routine returns #su_success (0), the sub-task is
* considered to be created successfully. After the successful
* initialization, the sub-task continues to execeute the function
* su_root_run().
*
* In single-threaded implementations, just a new root object is created.
* The initialization routine is called directly from su_clone_start().
*
* If the initalization function @a init fails, the sub-task (either the
* newly created thread or the current thread executing the su_clone_start()
* function) calls the deinitialization function, and su_clone_start()
* returns NULL.
*
* @param parent root to be cloned (may be NULL if multi-threaded)
* @param return_clone reference to a clone [OUT]
* @param magic pointer to user data
* @param init initialization function
* @param deinit deinitialization function
*
* @return 0 if successfull, -1 upon an error.
*
* @sa su_root_threading(), su_clone_task(), su_clone_stop(), su_clone_wait(),
* su_clone_forget().
*/
int su_clone_start(su_root_t *parent,
su_clone_r return_clone,
su_root_magic_t *magic,
su_root_init_f init,
su_root_deinit_f deinit)
{
su_root_t *child;
int retval = -1;
if (parent) {
assert(SU_ROOT_OWN_THREAD(parent));
assert(parent->sur_port);
}
#if !SU_HAVE_PTHREADS
else {
/* if we don't have threads, we *must* have parent root */
return -1;
}
#endif
child = su_salloc(NULL, sizeof(struct su_root_s));
#if SU_HAVE_PTHREADS
if (child && (parent == NULL || parent->sur_threading)) {
struct clone_args arg = {
NULL, NULL, NULL,
PTHREAD_MUTEX_INITIALIZER,
PTHREAD_COND_INITIALIZER,
-1,
SU_MSG_R_INIT,
NULL
};
int thread_created = 0;
pthread_t tid;
su_port_threadsafe(parent->sur_port);
arg.self = child;
arg.init = init;
arg.deinit = deinit;
arg.parent = parent;
child->sur_magic = magic;
child->sur_deinit = deinit;
child->sur_threading = parent->sur_threading;
SU_TASK_COPY(child->sur_parent, su_root_task(parent), su_clone_start);
pthread_mutex_lock(&arg.mutex);
if (pthread_create(&tid, NULL, su_clone_main, &arg) == 0) {
pthread_cond_wait(&arg.cv, &arg.mutex);
thread_created = 1;
}
pthread_mutex_unlock(&arg.mutex);
if (arg.retval != 0) {
if (thread_created)
pthread_join(tid, NULL);
su_root_destroy(child), child = NULL;
}
else {
retval = 0;
*return_clone = *arg.clone;
}
} else
#endif
if (child) {
assert(parent);
child->sur_magic = magic;
child->sur_deinit = deinit;
child->sur_threading = parent->sur_threading;
SU_TASK_COPY(child->sur_parent, su_root_task(parent), su_clone_start);
SU_TASK_COPY(child->sur_task, child->sur_parent, su_clone_start);
su_task_attach(child->sur_task, child);
if (su_msg_create(return_clone,
child->sur_task, su_root_task(parent),
su_clone_xyzzy, sizeof(child)) == 0) {
if (init == NULL || init(child, magic) == 0) {
su_cloned_t *sc = su_msg_data(return_clone);
sc->sc_root = child;
#if SU_HAVE_PTHREADS
sc->sc_tid = pthread_self();
pthread_mutex_init(sc->sc_pause, NULL);
pthread_cond_init(sc->sc_resume, NULL);
pthread_mutex_lock(sc->sc_pause);
#endif
retval = 0;
} else {
if (deinit)
deinit(child, magic);
su_msg_destroy(return_clone);
su_root_destroy(child), child = NULL;
}
}
else {
su_root_destroy(child), child = NULL;
}
}
return retval;
}
/** Get reference to clone task.
*
* @param clone Clone pointer
*
* @return A reference to the task structure of the clone.
*/
_su_task_r su_clone_task(su_clone_r clone)
{
return su_msg_to(clone);
}
/**Forget the clone.
*
* Normally, the clone task executes until it is stopped. If the parent
* task does not need to stop the task, it can "forget" the clone. The
* clone exits independently of the parent task.
*
* @param rclone Reference to the clone.
*/
void su_clone_forget(su_clone_r rclone)
{
su_msg_destroy(rclone);
}
/** Stop the clone.
*
* @deprecated. Use su_clone_wait().
*/
void su_clone_stop(su_clone_r rclone)
{
su_msg_send(rclone);
}
/** Stop a clone and wait until it is has completed.
*
* The function su_clone_wait() is used to stop the clone task and wait
* until it has cleaned up. The clone task is destroyed asynchronously. The
* parent sends a message to clone, clone deinitializes itself and then
* replies. After the reply message is received by the parent, it will send
* a third message back to clone.
*
* The parent destroy all messages to or from clone task before calling
* su_clone_wait(). The parent task may not send any messages to the clone
* after calling su_clone_wait(). The su_clone_wait() function blocks until
* the cloned task is destroyed. During that time, the parent task must be
* prepared to process all the messages sent by clone task. This includes
* all the messages sent by clone before destroy message reached the clone.
*/
void su_clone_wait(su_root_t *root, su_clone_r rclone)
{
su_cloned_t *sc = su_msg_data(rclone);
if (sc) {
#if SU_HAVE_PTHREADS
pthread_t clone_tid = sc->sc_tid;
#endif
int one = 1;
/* This does 3-way handshake.
* First, su_clone_break() is executed by clone.
* The message is returned to parent (this task),
* which executes su_clone_report().
* Then the message is again returned to clone,
* which executes su_clone_report2() and exits.
*/
sc->sc_wait = &one;
su_msg_send(rclone);
su_root_step(root, 0);
su_root_step(root, 0);
while (one)
su_root_step(root, 10);
#if SU_HAVE_PTHREADS
if (!pthread_equal(clone_tid, pthread_self()))
pthread_join(clone_tid, NULL);
#endif
}
}
#if SU_HAVE_PTHREADS /* No-op without threads */
static
void su_clone_paused(su_root_magic_t *magic, su_msg_r msg, su_msg_arg_t *arg)
{
su_cloned_t *cloned = *(su_cloned_t **)arg;
assert(cloned);
pthread_cond_wait(cloned->sc_resume, cloned->sc_pause);
}
#endif
/** Pause a clone.
*
* Obtain a exclusive lock on clone's private data.
*
* @retval 0 if successful (and clone is paused)
* @retval -1 upon an error
*/
int su_clone_pause(su_clone_r rclone)
{
#if SU_HAVE_PTHREADS /* No-op without threads */
su_cloned_t *cloned = su_msg_data(rclone);
su_msg_r m = SU_MSG_R_INIT;
if (!cloned)
return (errno = EFAULT), -1;
if (pthread_equal(pthread_self(), cloned->sc_tid))
return 0;
if (su_msg_create(m, su_clone_task(rclone), su_task_null,
su_clone_paused, sizeof cloned) < 0)
return -1;
*(su_cloned_t **)su_msg_data(m) = cloned;
if (su_msg_send(m) < 0)
return -1;
if (pthread_mutex_lock(cloned->sc_pause) < 0)
return -1;
pthread_cond_signal(cloned->sc_resume);
#endif
return 0;
}
/** Resume a clone.
*
* Give up a exclusive lock on clone's private data.
*
* @retval 0 if successful (and clone is resumed)
* @retval -1 upon an error
*/
int su_clone_resume(su_clone_r rclone)
{
#if SU_HAVE_PTHREADS /* No-op without threads */
su_cloned_t *cloned = su_msg_data(rclone);
if (!cloned)
return (errno = EFAULT), -1;
if (pthread_equal(pthread_self(), cloned->sc_tid))
return 0;
if (pthread_mutex_unlock(cloned->sc_pause) < 0)
return -1;
#endif
return 0;
}
/* =========================================================================
* Messages
*/
/**
* Allocates a message of given size.
*
* The function @c su_msg_create() allocates a message with given data size.
* If successful, it moves the new message handle to the @c rmsg.
*
* @param rmsg handle to the new message (may be uninitialized prior calling)
* @param to the recipient task
* @param from the sender task
* @param wakeup function that is called when message is delivered
* @param size size of the message data
*
* @retval 0 if successful,
* @retval -1 if message allocation fails.
*/
int su_msg_create(su_msg_r rmsg,
su_task_r const to,
su_task_r const from,
su_msg_f wakeup,
isize_t size)
{
su_port_t *port = to->sut_port;
su_msg_t *msg;
SU_PORT_LOCK(port, su_msg_create);
msg = su_zalloc(NULL /*port->sup_home*/, sizeof(*msg) + size);
SU_PORT_UNLOCK(port, su_msg_create);
if (msg) {
msg->sum_size = sizeof(*msg) + size;
SU_TASK_COPY(msg->sum_to, to, su_msg_create);
SU_TASK_COPY(msg->sum_from, from, su_msg_create);
msg->sum_func = wakeup;
*rmsg = msg;
return 0;
}
*rmsg = NULL;
return -1;
}
/** Add a delivery report function to a message.
*
* The delivery report funcgtion gets called by the sending task after the
* message was delivered and the message function was executed. (The
* su_root_t message delivery loop calls su_msg_delivery_report()
*
*/
int su_msg_report(su_msg_r msg,
su_msg_f report)
{
if (msg && msg[0] && msg[0]->sum_report == NULL) {
msg[0]->sum_report = report;
return 0;
}
return -1;
}
/**
* Allocates a reply message of given size.
*
* @param reply handle to the new message (may be uninitialized prior calling)
* @param msg the incoming message
* @param wakeup function that is called when message is delivered
* @param size size of the message data
*
* @retval 0 if successful,
* @retval -1 otherwise.
*/
int su_msg_reply(su_msg_r reply, su_msg_r const msg,
su_msg_f wakeup, isize_t size)
{
su_msg_r msg0;
assert(msg != reply);
*msg0 = *msg;
*reply = NULL;
return su_msg_create(reply, su_msg_from(msg0), su_msg_to(msg0), wakeup, size);
}
/** Send a delivery report.
*
* If the sender has attached a delivery report function to message with
* su_msg_report(), the message is returned to the message queue of the
* sending task. The sending task calls the delivery report function when it
* has received the message.
*/
void su_msg_delivery_report(su_msg_r msg)
{
su_task_r swap;
if (!msg || !msg[0])
return;
if (!msg[0]->sum_report) {
su_msg_destroy(msg);
return;
}
*swap = *msg[0]->sum_from;
*msg[0]->sum_from = *msg[0]->sum_to;
*msg[0]->sum_to = *swap;
msg[0]->sum_func = msg[0]->sum_report;
msg[0]->sum_report = NULL;
su_msg_send(msg);
}
/** Save a message. */
void su_msg_save(su_msg_r save, su_msg_r msg)
{
if (save) {
if (msg)
save[0] = msg[0];
else
save[0] = NULL;
}
if (msg)
msg[0] = NULL;
}
/**
* Destroys an unsent message.
*
* @param rmsg message handle.
*/
void su_msg_destroy(su_msg_r rmsg)
{
assert(rmsg);
if (rmsg[0]) {
/* su_port_t *port = rmsg[0]->sum_to->sut_port; */
/* SU_PORT_INCREF(port, su_msg_destroy); */
SU_TASK_ZAP(rmsg[0]->sum_to, su_msg_destroy);
SU_TASK_ZAP(rmsg[0]->sum_from, su_msg_destroy);
su_free(NULL /* port->sup_home */, rmsg[0]);
/* SU_PORT_UNLOCK(port, su_msg_destroy); */
/* SU_PORT_DECREF(port, su_msg_destroy); */
}
rmsg[0] = NULL;
}
/** Gets a pointer to the message data area.
*
* The function @c su_msg_data() returns a pointer to the message data
* area. If @c rmsg contains a @c NULL handle, or message size is 0, @c NULL
* pointer is returned.
*
* @param rmsg message handle
*
* @return A pointer to the message data area is returned.
*/
su_msg_arg_t *su_msg_data(su_msg_cr rmsg)
{
if (rmsg[0] && rmsg[0]->sum_size > sizeof(su_msg_t))
return rmsg[0]->sum_data;
else
return NULL;
}
/** Get size of message data area. */
isize_t su_msg_size(su_msg_cr rmsg)
{
return rmsg[0] ? rmsg[0]->sum_size - sizeof(su_msg_t) : 0;
}
/** Get sending task.
*
* Returns the task handle belonging to the sender of the message.
*
* If the message handle contains NULL the function @c su_msg_from
* returns NULL.
*
* @param msg message handle
*
* @return The task handle of the sender is returned.
*/
_su_task_r su_msg_from(su_msg_r const msg)
{
return msg[0] ? msg[0]->sum_from : NULL;
}
/** Get destination task.
*
* The function @c su_msg_from returns the task handle belonging to the
* recipient of the message.
*
* If the message handle contains NULL the function @c su_msg_to
* returns NULL.
*
* @param msg message handle
*
* @return The task handle of the recipient is returned.
*/
_su_task_r su_msg_to(su_msg_r const msg)
{
return msg[0] ? msg[0]->sum_to : NULL;
}
/** Remove references to 'from' and 'to' tasks from a message.
*
* @param msg message handle
*/
void su_msg_remove_refs(su_msg_r const msg)
{
if (msg[0]) {
su_task_deinit(msg[0]->sum_to);
su_task_deinit(msg[0]->sum_from);
}
}
/**Send a message.
*
* The function @c su_msg_send() sends the message. The message is added to
* the recipients message queue, and recipient is waken up. The caller may
* not alter the message or the data associated with it after the message
* has been sent.
*
* @param rmsg message handle
*
* @retval 0 if signal was sent successfully or handle was @c NULL,
* @retval -1 otherwise.
*/
int su_msg_send(su_msg_r rmsg)
{
assert(rmsg);
if (rmsg[0]) {
su_msg_t *msg = rmsg[0];
assert(msg->sum_to->sut_port);
return su_port_send(msg->sum_to->sut_port, rmsg);
}
return 0;
}