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Tim's changes; removed some remaining non-functional ifdefs

This commit is contained in:
Guido van Rossum 1994-05-11 08:42:04 +00:00
parent 2c8cb9f3d2
commit b98b1b3deb
3 changed files with 86 additions and 91 deletions
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4
Python/thread_cthread.h
View File

@ -38,10 +38,6 @@ static void _init_thread _P0()
*/
int start_new_thread _P2(func, void (*func) _P((void *)), arg, void *arg)
{
#if defined(SGI_THREADS) && defined(USE_DL)
long addr, size;
static int local_initialized = 0;
#endif /* SGI_THREADS and USE_DL */
int success = 0; /* init not needed when SOLARIS_THREADS and */
/* C_THREADS implemented properly */

4
Python/thread_lwp.h
View File

@ -52,10 +52,6 @@ static void _init_thread _P0()
int start_new_thread _P2(func, void (*func) _P((void *)), arg, void *arg)
{
thread_t tid;
#if defined(SGI_THREADS) && defined(USE_DL)
long addr, size;
static int local_initialized = 0;
#endif /* SGI_THREADS and USE_DL */
int success = 0; /* init not needed when SOLARIS_THREADS and */
/* C_THREADS implemented properly */

169
Python/thread_pthread.h
View File

@ -29,7 +29,7 @@ OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
#ifdef FLORIDA_HACKS
/* Hacks for Florida State Posix threads implementation */
#undef _POSIX_THREADS
#include "/ufs/guido/src/python/Contrib/pthreads/pthreads/pthread.h"
#include "/ufs/guido/src/python/Contrib/pthreads/src/pthread.h"
#define pthread_attr_default ((pthread_attr_t *)0)
#define pthread_mutexattr_default ((pthread_mutexattr_t *)0)
#define pthread_condattr_default ((pthread_condattr_t *)0)
@ -40,26 +40,30 @@ OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
#endif /* FLORIDA_HACKS */
#include <stdlib.h>
/* A pthread mutex isn't sufficient to model the Python lock type (at
* least not the way KSR did 'em -- haven't dug thru the docs to verify),
* because a thread that locks a mutex can't then do a pthread_mutex_lock
* on it (to wait for another thread to unlock it).
* In any case, pthread mutexes are designed for serializing threads over
* short pieces of code, so wouldn't be an appropriate implementation of
/* A pthread mutex isn't sufficient to model the Python lock type
* because, according to Draft 5 of the docs (P1003.4a/D5), both of the
* following are undefined:
* -> a thread tries to lock a mutex it already has locked
* -> a thread tries to unlock a mutex locked by a different thread
* pthread mutexes are designed for serializing threads over short pieces
* of code anyway, so wouldn't be an appropriate implementation of
* Python's locks regardless.
* The pthread_lock struct below implements a Python lock as a pthread
* mutex and a <condition, mutex> pair. In general, if the mutex can be
* be acquired instantly, it is, else the pair is used to block the
* thread until the mutex is released. 7 May 1994 tim@ksr.com
*
* The pthread_lock struct implements a Python lock as a "locked?" bit
* and a <condition, mutex> pair. In general, if the bit can be acquired
* instantly, it is, else the pair is used to block the thread until the
* bit is cleared. 9 May 1994 tim@ksr.com
*/
typedef struct {
/* the lock */
pthread_mutex_t mutex;
/* a <cond, mutex> pair to handle an acquire of a locked mutex */
pthread_cond_t cond;
pthread_mutex_t cmutex;
char locked; /* 0=unlocked, 1=locked */
/* a <cond, mutex> pair to handle an acquire of a locked lock */
pthread_cond_t lock_released;
pthread_mutex_t mut;
} pthread_lock;
#define CHECK_STATUS(name) if (status < 0) { perror(name); error=1; }
/*
* Initialization.
*/
@ -70,6 +74,8 @@ static void _init_thread _P0()
/*
* Thread support.
*/
int start_new_thread _P2(func, void (*func) _P((void *)), arg, void *arg)
{
#if defined(SGI_THREADS) && defined(USE_DL)
@ -135,30 +141,25 @@ void _exit_prog _P1(status, int status)
type_lock allocate_lock _P0()
{
pthread_lock *lock;
int status, error = 0;
dprintf(("allocate_lock called\n"));
if (!initialized)
init_thread();
lock = (pthread_lock *) malloc(sizeof(pthread_lock));
{
int err = 0;
if ( pthread_mutex_init(&lock->mutex,
pthread_mutexattr_default) ) {
perror("pthread_mutex_init");
err = 1;
}
if ( pthread_cond_init(&lock->cond,
pthread_condattr_default) ) {
perror("pthread_cond_init");
err = 1;
}
if ( pthread_mutex_init(&lock->cmutex,
pthread_mutexattr_default)) {
perror("pthread_mutex_init");
err = 1;
}
if (err) {
if (lock) {
lock->locked = 0;
status = pthread_mutex_init(&lock->mut,
pthread_mutexattr_default);
CHECK_STATUS("pthread_mutex_init");
status = pthread_cond_init(&lock->lock_released,
pthread_condattr_default);
CHECK_STATUS("pthread_cond_init");
if (error) {
free((void *)lock);
lock = 0;
}
@ -170,80 +171,82 @@ type_lock allocate_lock _P0()
void free_lock _P1(lock, type_lock lock)
{
pthread_lock *thelock = (pthread_lock *)lock;
int status, error = 0;
dprintf(("free_lock(%lx) called\n", (long)lock));
if ( pthread_mutex_destroy(&((pthread_lock *)lock)->mutex) )
perror("pthread_mutex_destroy");
if ( pthread_cond_destroy(&((pthread_lock *)lock)->cond) )
perror("pthread_cond_destroy");
if ( pthread_mutex_destroy(&((pthread_lock *)lock)->cmutex) )
perror("pthread_mutex_destroy");
free((void *)lock);
status = pthread_mutex_destroy( &thelock->mut );
CHECK_STATUS("pthread_mutex_destroy");
status = pthread_cond_destroy( &thelock->lock_released );
CHECK_STATUS("pthread_cond_destroy");
free((void *)thelock);
}
int acquire_lock _P2(lock, type_lock lock, waitflag, int waitflag)
{
int success;
pthread_lock *thelock = (pthread_lock *)lock;
int status, error = 0;
dprintf(("acquire_lock(%lx, %d) called\n", (long)lock, waitflag));
{
pthread_lock *thelock = (pthread_lock *)lock;
success = TRYLOCK_OFFSET +
pthread_mutex_trylock( &thelock->mutex );
if (success < 0) {
perror("pthread_mutex_trylock [1]");
success = 0;
} else if ( success == 0 && waitflag ) {
/* continue trying until we get the lock */
/* cmutex must be locked by me -- part of the condition
* protocol */
if ( pthread_mutex_lock( &thelock->cmutex ) )
perror("pthread_mutex_lock");
while ( 0 == (success = TRYLOCK_OFFSET +
pthread_mutex_trylock(&thelock->mutex)) ) {
if ( pthread_cond_wait(&thelock->cond,
&thelock->cmutex) )
perror("pthread_cond_wait");
}
if (success < 0)
perror("pthread_mutex_trylock [2]");
/* now ->mutex & ->cmutex are both locked by me */
if ( pthread_mutex_unlock( &thelock->cmutex ) )
perror("pthread_mutex_unlock");
status = pthread_mutex_lock( &thelock->mut );
CHECK_STATUS("pthread_mutex_lock[1]");
success = thelock->locked == 0;
if (success) thelock->locked = 1;
status = pthread_mutex_unlock( &thelock->mut );
CHECK_STATUS("pthread_mutex_unlock[1]");
if ( !success && waitflag ) {
/* continue trying until we get the lock */
/* mut must be locked by me -- part of the condition
* protocol */
status = pthread_mutex_lock( &thelock->mut );
CHECK_STATUS("pthread_mutex_lock[2]");
while ( thelock->locked ) {
status = pthread_cond_wait(&thelock->lock_released,
&thelock->mut);
CHECK_STATUS("pthread_cond_wait");
}
thelock->locked = 1;
status = pthread_mutex_unlock( &thelock->mut );
CHECK_STATUS("pthread_mutex_unlock[2]");
success = 1;
}
if (error) success = 0;
dprintf(("acquire_lock(%lx, %d) -> %d\n", (long)lock, waitflag, success));
return success;
}
void release_lock _P1(lock, type_lock lock)
{
pthread_lock *thelock = (pthread_lock *)lock;
int status, error = 0;
dprintf(("release_lock(%lx) called\n", (long)lock));
{
pthread_lock *thelock = (pthread_lock *)lock;
/* tricky: if the release & signal occur between the
* pthread_mutex_trylock(&thelock->mutex))
* and pthread_cond_wait during the acquire, the acquire
* will miss the signal it's waiting for; locking cmutex
* around the release prevents that
*/
if (pthread_mutex_lock( &thelock->cmutex ))
perror("pthread_mutex_lock");
if (pthread_mutex_unlock( &thelock->mutex ))
perror("pthread_mutex_unlock");
if (pthread_mutex_unlock( &thelock->cmutex ))
perror("pthread_mutex_unlock");
status = pthread_mutex_lock( &thelock->mut );
CHECK_STATUS("pthread_mutex_lock[3]");
/* wake up someone (anyone, if any) waiting on the lock */
if (pthread_cond_signal( &thelock->cond ))
perror("pthread_cond_signal");
}
thelock->locked = 0;
status = pthread_mutex_unlock( &thelock->mut );
CHECK_STATUS("pthread_mutex_unlock[3]");
/* wake up someone (anyone, if any) waiting on the lock */
status = pthread_cond_signal( &thelock->lock_released );
CHECK_STATUS("pthread_cond_signal");
}
/*
* Semaphore support.
*/
/* NOTE: 100% non-functional at this time - tim */
type_sema allocate_sema _P1(value, int value)
{
char *sema = 0;