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/*
* cleanup.c
*
* Description:
* This translation unit implements routines associated cleaning up
* threads.
*/
#include "pthread.h"
#include "implement.h"
int
_pthread_handler_push(int stack,
int poporder,
void (*routine)(void *),
void *arg)
{
/* Place the new handler into the list so that handlers are
popped off in the order given by poporder. */
_pthread_handler_node_t * new_thread;
_pthread_handler_node_t * next;
_pthread_handler_node_t ** stacktop;
stacktop = _PTHREAD_STACK(stack);
new_thread =
(_pthread_handler_node_t *) malloc(sizeof(_pthread_handler_node_t));
if (new_thread == NULL)
{
return ENOMEM;
}
new_thread->routine = routine;
new_thread->arg = arg;
if (poporder == _PTHREAD_HANDLER_POP_LIFO)
{
/* Add the new node to the start of the list. */
new_thread->next = *stacktop;
*stacktop = next;
}
else
{
/* Add the new node to the end of the list. */
new_thread->next = NULL;
if (*stacktop == NULL)
{
*stacktop = new_thread;
}
else
{
next = *stacktop;
while (next != NULL)
{
next = next->next;
}
next = new_thread;
}
}
return 0;
}
void
_pthread_handler_pop(int stack, int execute)
{
_pthread_handler_node_t ** stacktop;
_pthread_handler_node_t * next;
void (* func)(void *);
void * arg;
stacktop = _PTHREAD_STACK(stack);
if (*stacktop != NULL)
{
func = (*stacktop)->routine;
arg = (*stacktop)->arg;
next = (*stacktop)->next;
free(*stacktop);
*stacktop = next;
if (execute != 0 && func != NULL)
{
(void) func(arg);
}
}
}
void
_pthread_handler_pop_all(int stack, int execute)
{
/* Pop and possibly run all handlers on the given stack. */
_pthread_handler_node_t ** stacktop;
_pthread_handler_node_t * next;
void (* func)(void *);
void * arg;
stacktop = _PTHREAD_STACK(stack);
while (*stacktop != NULL)
{
func = (*stacktop)->routine;
arg = (*stacktop)->arg;
next = (*stacktop)->next;
free(*stacktop);
*stacktop = next;
if (execute != 0 && func != NULL)
{
(void) func(arg);
}
}
}
int
_pthread_destructor_push(void (* routine)(void *), pthread_key_t key)
{
return _pthread_handler_push(_PTHREAD_DESTRUCTOR_STACK,
_PTHREAD_HANDLER_POP_LIFO,
routine,
key);
}
/* Remove all of the destructors associated with the key. */
void
_pthread_destructor_pop(pthread_key_t key)
{
_pthread_handler_node_t ** head;
_pthread_handler_node_t * current;
_pthread_handler_node_t * next;
head = _PTHREAD_STACK(_PTHREAD_DESTRUCTOR_STACK);
current = *head;
while (current != NULL)
{
next = current->next;
/* The destructors associated key is in current->arg. */
if (current->arg == key)
{
if (current == *head)
{
*head = next;
}
free(current);
}
current = next;
}
}
/* Run destructors for all non-NULL key values.
FIXME: Currently we only run the destructors on the calling
thread's key values. The way I interpret POSIX semantics is that,
for each key that the calling thread has a destructor for, we need
to look at the key values of every thread and run the destructor on
it if the key value is non-NULL.
The question is: how do we access the key associated values which
are private to other threads?
*/
void
_pthread_destructor_pop_all()
{
_pthread_handler_node_t ** head;
_pthread_handler_node_t * current;
_pthread_handler_node_t * next;
void (* func)(void *);
void * arg;
int count;
head = _PTHREAD_STACK(_PTHREAD_DESTRUCTOR_STACK);
/* Stop destructor execution at a finite time. POSIX allows us
to ignore this if we like, even at the risk of an infinite loop.
*/
for (count = 0; count < PTHREAD_DESTRUCTOR_ITERATIONS; count++)
{
/* Loop through all destructors for this thread. */
while (current != NULL)
{
func = current->routine;
/* Get the key value using the key which is in current->arg. */
arg = pthread_getspecific(current->arg);
next = current->next;
/* If the key value is non-NULL run the destructor, otherwise
unlink it from the list.
*/
if (arg != NULL)
{
if (func != NULL)
{
(void) func(arg);
}
}
else
{
if (current == *head)
{
*head = next;
}
free(current);
}
current = next;
}
}
/* Free the destructor list even if we still have non-NULL key values. */
while (*head != NULL)
{
next = (*head)->next;
free(*head);
*head = next;
}
}
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