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riscv-gcc-1
Commit f4d01e79 by Richard Kenner
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(objc_condition_{,de}allocate): New functions. 

(objc_condition_{wait,broadcast,signal}): New functions.
(__objc_runtime_mutex): Eliminate leading underscore from name of objc mutex
and thread structures.

From-SVN: r13595
parent 3136f75d
Showing with 131 additions and 26 deletions
gcc/objc/thr-pthreads.c
/* GNU Objective C Runtime Thread Implementation for PCThreads under Linux.
Copyright (C) 1996 Free Software Foundation, Inc.
Copyright (C) 1996, 1997 Free Software Foundation, Inc.
Contributed by Scott Christley <scottc@net-community.com>
This file is part of GNU CC.
......@@ -37,13 +37,18 @@ static pthread_key_t _objc_thread_storage;
* provided by the system. We augment it with depth and current owner id
* fields to implement and re-entrant lock.
*/
struct _objc_mutex
struct objc_mutex
{
volatile _objc_thread_t owner; /* Id of thread that owns. */
volatile objc_thread_t owner; /* Id of thread that owns. */
volatile int depth; /* # of acquires. */
pthread_mutex_t mutex; /* PCThread mutex */
};
struct objc_condition
{
pthread_cond_t condition; /* cthread condition */
};
/********
* Initialize the threads subsystem. Returns 0 if successful, or -1 if no
* thread support is available.
......@@ -71,17 +76,17 @@ __objc_fini_thread_system(void)
* Create a new thread of execution and return its id. Return NULL if fails.
* The new thread starts in "func" with the given argument.
*/
_objc_thread_t
objc_thread_t
objc_thread_create(void (*func)(void *arg), void *arg)
{
_objc_thread_t thread_id;
objc_thread_t thread_id;
pthread_t new_thread_handle;
objc_mutex_lock(__objc_runtime_mutex);
if ( !(pthread_create(&new_thread_handle, NULL, (void *)func, arg)) )
{
thread_id = *(_objc_thread_t *)&new_thread_handle;
thread_id = *(objc_thread_t *)&new_thread_handle;
__objc_runtime_threads_alive++;
}
else
......@@ -99,7 +104,7 @@ int
objc_thread_set_priority(int priority)
{
/* Not implemented yet */
return -1; /* Failed. */
return -1; /* Failed. */
}
/********
......@@ -109,7 +114,7 @@ int
objc_thread_get_priority(void)
{
/* Not implemented yet */
return OBJC_THREAD_INTERACTIVE_PRIORITY; /* Highest priority. */
return OBJC_THREAD_INTERACTIVE_PRIORITY; /* Highest priority. */
}
/********
......@@ -134,7 +139,7 @@ objc_thread_exit(void)
__objc_runtime_threads_alive--;
objc_mutex_unlock(__objc_runtime_mutex);
pthread_exit(&__objc_thread_exit_status); /* Terminate thread. */
pthread_exit(&__objc_thread_exit_status); /* Terminate thread. */
return -1;
}
......@@ -142,12 +147,12 @@ objc_thread_exit(void)
* Returns an integer value which uniquely describes a thread. Must not be
* NULL which is reserved as a marker for "no thread".
*/
_objc_thread_t
objc_thread_t
objc_thread_id(void)
{
pthread_t self = pthread_self();
return *(_objc_thread_t *)&self; /* Return thread handle. */
return *(objc_thread_t *)&self; /* Return thread handle. */
}
/********
......@@ -178,12 +183,12 @@ objc_thread_get_data(void)
* Allocate a mutex. Return the mutex pointer if successful or NULL if the
* allocation failed for any reason.
*/
_objc_mutex_t
objc_mutex_t
objc_mutex_allocate(void)
{
_objc_mutex_t mutex;
objc_mutex_t mutex;
if (!(mutex = (_objc_mutex_t) objc_malloc(sizeof(struct _objc_mutex))))
if (!(mutex = (objc_mutex_t)objc_malloc(sizeof(struct objc_mutex))))
return NULL; /* Abort if malloc failed. */
/* Create PCThread mutex */
......@@ -207,7 +212,7 @@ objc_mutex_allocate(void)
* Returns the number of locks on the thread. (1 for deallocate).
*/
int
objc_mutex_deallocate(_objc_mutex_t mutex)
objc_mutex_deallocate(objc_mutex_t mutex)
{
int depth; /* # of locks on mutex. */
......@@ -229,9 +234,9 @@ objc_mutex_deallocate(_objc_mutex_t mutex)
* Returns the lock count on the mutex held by this thread.
*/
int
objc_mutex_lock(_objc_mutex_t mutex)
objc_mutex_lock(objc_mutex_t mutex)
{
_objc_thread_t thread_id; /* Cache our thread id. */
objc_thread_t thread_id; /* Cache our thread id. */
int status;
if (!mutex) /* Is argument bad? */
......@@ -259,9 +264,9 @@ objc_mutex_lock(_objc_mutex_t mutex)
* thread has a lock on the mutex returns -1.
*/
int
objc_mutex_trylock(_objc_mutex_t mutex)
objc_mutex_trylock(objc_mutex_t mutex)
{
_objc_thread_t thread_id; /* Cache our thread id. */
objc_thread_t thread_id; /* Cache our thread id. */
int status;
if (!mutex) /* Is argument bad? */
......@@ -280,16 +285,16 @@ objc_mutex_trylock(_objc_mutex_t mutex)
}
/********
* Decrements the lock count on this mutex by one. If the lock count reaches
* zero, release the lock on the mutex. Returns the lock count on the mutex.
* It is an error to attempt to unlock a mutex which this thread doesn't hold
* in which case return -1 and the mutex is unaffected.
* Will also return -1 if the mutex free fails.
* Decrements the lock count on this mutex by one. If the lock count reaches
* zero, release the lock on the mutex. Returns the lock count on the mutex.
* It is an error to attempt to unlock a mutex which this thread doesn't hold
* in which case return -1 and the mutex is unaffected.
* Will also return -1 if the mutex free fails.
*/
int
objc_mutex_unlock(_objc_mutex_t mutex)
objc_mutex_unlock(objc_mutex_t mutex)
{
_objc_thread_t thread_id; /* Cache our thread id. */
objc_thread_t thread_id; /* Cache our thread id. */
int status;
if (!mutex) /* Is argument bad? */
......@@ -310,4 +315,104 @@ objc_mutex_unlock(_objc_mutex_t mutex)
return 0; /* No, return success. */
}
/********
* Allocate a condition. Return the condition pointer if successful or NULL
* if the allocation failed for any reason.
*/
objc_condition_t
objc_condition_allocate(void)
{
objc_condition_t condition;
if (!(condition = (objc_condition_t)objc_malloc(
sizeof(struct objc_condition))))
return NULL; /* Abort if malloc failed. */
if ( pthread_cond_init(&(condition->condition), NULL) ) {
objc_free(condition);
return NULL;
}
return condition; /* Return condition handle. */
}
/********
* Deallocate a condition. Note that this includes an implicit
* condition_broadcast to insure that waiting threads have the opportunity
* to wake. It is legal to dealloc a condition only if no other
* thread is/will be using it. Here we do NOT check for other threads
* waiting but just wake them up.
*/
int
objc_condition_deallocate(objc_condition_t condition)
{
pthread_cond_broadcast(&(condition->condition));
pthread_cond_destroy(&(condition->condition));
objc_free(condition);
return 0;
}
/********
* Wait on the condition unlocking the mutex until objc_condition_signal()
* or objc_condition_broadcast() are called for the same condition. The
* given mutex *must* have the depth set to 1 so that it can be unlocked
* here, so that someone else can lock it and signal/broadcast the condition.
* The mutex is used to lock access to the shared data that make up the
* "condition" predicate.
*/
int
objc_condition_wait(objc_condition_t condition, objc_mutex_t mutex)
{
objc_thread_t thread_id; /* Cache our thread id. */
if (!mutex || !condition) /* Is argument bad? */
return -1; /* Yes, abort. */
thread_id = objc_thread_id(); /* Get this thread's id. */
if (mutex->owner != thread_id) /* Does some else own lock? */
return -1; /* Yes, abort. */
if (mutex->depth > 1) /* Locked more than once ? */
return -1; /* YES, return error */
/* mutex will be unlocked */
mutex->depth = 0; /* Yes, reset depth to 0. */
mutex->owner = (objc_thread_t) -1; /* Set owner to "no thread".*/
pthread_cond_wait(&(condition->condition),
&(mutex->mutex)); /* unlock, wait ..., lock */
mutex->owner = thread_id; /* Mark thread as owner. */
mutex->depth = 1; /* Increment depth to end. */
return 0; /* Return success. */
}
/********
* Wake up all threads waiting on this condition. It is recommended that
* the called would lock the same mutex as the threads in objc_condition_wait
* before changing the "condition predicate" and make this call and unlock it
* right away after this call.
*/
int
objc_condition_broadcast(objc_condition_t condition)
{
if (!condition)
return -1;
pthread_cond_broadcast(&(condition->condition));
return 0;
}
/********
* Wake up one thread waiting on this condition. It is recommended that
* the called would lock the same mutex as the threads in objc_condition_wait
* before changing the "condition predicate" and make this call and unlock it
* right away after this call.
*/
int
objc_condition_signal(objc_condition_t condition)
{
if (!condition)
return -1;
pthread_cond_signal(&(condition->condition));
return 0;
}
/* End of File */
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