[vlc-devel] [PATCH] android: threads support
Rafaël Carré
funman at videolan.org
Mon Oct 8 12:08:50 CEST 2012
---
v4:
- add __ANDROID__ part in vlc_threads.h
- optimize vlc_join() fast path
- add comment in msleep() about drift
include/vlc_threads.h | 27 ++-
src/Makefile.am | 2 +-
src/android/thread.c | 487 +++++++++++++++++++++++++++++++++++++++++++++++++
3 files changed, 512 insertions(+), 4 deletions(-)
create mode 100644 src/android/thread.c
diff --git a/include/vlc_threads.h b/include/vlc_threads.h
index cc0e8b1..a199033 100644
--- a/include/vlc_threads.h
+++ b/include/vlc_threads.h
@@ -42,6 +42,15 @@
# define pthread_sigmask sigprocmask
+#elif defined( __ANDROID__ ) /* pthreads subset without pthread_cancel() */
+
+# define LIBVLC_NEED_SEMAPHORE
+# define LIBVLC_NEED_RWLOCK
+
+# include <unistd.h> /* _POSIX_SPIN_LOCKS */
+# include <pthread.h>
+# include <poll.h>
+
#else /* pthreads (like Linux & BSD) */
# define LIBVLC_USE_PTHREAD 1
# define LIBVLC_USE_PTHREAD_CANCEL 1
@@ -73,7 +82,7 @@
# define VLC_THREAD_PRIORITY_OUTPUT 22
# define VLC_THREAD_PRIORITY_HIGHEST 22
-#elif defined(LIBVLC_USE_PTHREAD)
+#elif defined(LIBVLC_USE_PTHREAD) || defined(__ANDROID__)
# define VLC_THREAD_PRIORITY_LOW 0
# define VLC_THREAD_PRIORITY_INPUT 10
# define VLC_THREAD_PRIORITY_AUDIO 5
@@ -116,7 +125,17 @@
* Type definitions
*****************************************************************************/
-#if defined (LIBVLC_USE_PTHREAD)
+#if defined (__ANROID__)
+typedef struct vlc_thread *vlc_thread_t;
+typedef pthread_mutex_t vlc_mutex_t;
+#define VLC_STATIC_MUTEX PTHREAD_MUTEX_INITIALIZER
+typedef pthread_cond_t vlc_cond_t;
+#define VLC_STATIC_COND PTHREAD_COND_INITIALIZER
+
+typedef pthread_key_t vlc_threadvar_t;
+typedef struct vlc_timer *vlc_timer_t;
+
+#elif defined (LIBVLC_USE_PTHREAD)
typedef pthread_t vlc_thread_t;
typedef pthread_mutex_t vlc_mutex_t;
#define VLC_STATIC_MUTEX PTHREAD_MUTEX_INITIALIZER
@@ -332,7 +351,7 @@ VLC_API int vlc_savecancel(void);
VLC_API void vlc_restorecancel(int state);
VLC_API void vlc_testcancel(void);
-#if defined (LIBVLC_USE_PTHREAD_CANCEL)
+#if defined (LIBVLC_USE_PTHREAD_CANCEL) || defined(__ANDROID__)
/**
* Registers a new procedure to run if the thread is cancelled (or otherwise
* exits prematurely). Any call to vlc_cleanup_push() <b>must</b> paired with a
@@ -383,7 +402,9 @@ struct vlc_cleanup_t
vlc_control_cancel (VLC_CLEANUP_POP); \
vlc_cleanup_data.proc (vlc_cleanup_data.data); \
} while (0)
+#endif /* LIBVLC_USE_PTHREAD_CANCEL || __ANDROID__ */
+#if !defined (LIBVLC_USE_PTHREAD_CANCEL)
/* poll() with cancellation */
static inline int vlc_poll (struct pollfd *fds, unsigned nfds, int timeout)
{
diff --git a/src/Makefile.am b/src/Makefile.am
index 9d1d87d..ab8c46c 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -259,9 +259,9 @@ SOURCES_libvlc_darwin = \
SOURCES_libvlc_android = \
android/dirs.c \
+ android/thread.c \
posix/filesystem.c \
posix/plugin.c \
- posix/thread.c \
posix/timer.c \
posix/linux_cpu.c \
posix/linux_specific.c \
diff --git a/src/android/thread.c b/src/android/thread.c
new file mode 100644
index 0000000..c6bdacf
--- /dev/null
+++ b/src/android/thread.c
@@ -0,0 +1,487 @@
+/*****************************************************************************
+ * thread.c : android pthread back-end for LibVLC
+ *****************************************************************************
+ * Copyright (C) 1999-2012 VLC authors and VideoLAN
+ *
+ * Authors: Jean-Marc Dressler <polux at via.ecp.fr>
+ * Samuel Hocevar <sam at zoy.org>
+ * Gildas Bazin <gbazin at netcourrier.com>
+ * Clément Sténac
+ * Rémi Denis-Courmont
+ *
+ * This program 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 program 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 program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
+ *****************************************************************************/
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <vlc_common.h>
+#include <vlc_atomic.h>
+
+#include "libvlc.h"
+#include <signal.h>
+#include <errno.h>
+#include <time.h>
+
+#include <sys/types.h>
+#include <unistd.h> /* fsync() */
+#include <pthread.h>
+#include <sched.h>
+
+#include <android/log.h>
+#include <sys/syscall.h> /* __NR_gettid */
+
+/* FIXME: Android has a monotonic clock
+ * XXX : how to use it with pthread_cond_wait() ? */
+# warning Monotonic clock not available. Expect timing issues.
+
+/* helper */
+static struct timespec mtime_to_ts (mtime_t date)
+{
+ lldiv_t d = lldiv (date, CLOCK_FREQ);
+ struct timespec ts = { d.quot, d.rem * (1000000000 / CLOCK_FREQ) };
+
+ return ts;
+}
+
+/* debug */
+#define vlc_assert(x) do { \
+ if (unlikely(!x)) { \
+ __android_log_print(ANDROID_LOG_ERROR, "vlc", "assert failed %s:%d: %s", \
+ __FILE__, __LINE__, #x \
+ ); \
+ abort(); \
+ } \
+} while(0)
+
+#ifndef NDEBUG
+static void
+vlc_thread_fatal (const char *action, int error,
+ const char *function, const char *file, unsigned line)
+{
+ char buf[1000];
+ const char *msg;
+
+ switch (strerror_r (error, buf, sizeof (buf)))
+ {
+ case 0:
+ msg = buf;
+ break;
+ case ERANGE: /* should never happen */
+ msg = "unknown (too big to display)";
+ break;
+ default:
+ msg = "unknown (invalid error number)";
+ break;
+ }
+
+ __android_log_print(ANDROID_LOG_ERROR, "vlc",
+ "LibVLC fatal error %s (%d) in thread %d "
+ "at %s:%u in %s\n Error message: %s\n",
+ action, error, syscall (__NR_gettid), file, line, function, msg);
+
+ abort ();
+}
+
+# define VLC_THREAD_ASSERT( action ) \
+ if (unlikely(val)) \
+ vlc_thread_fatal (action, val, __func__, __FILE__, __LINE__)
+#else
+# define VLC_THREAD_ASSERT( action ) ((void)val)
+#endif
+
+/* mutexes */
+void vlc_mutex_init( vlc_mutex_t *p_mutex )
+{
+ pthread_mutexattr_t attr;
+
+ pthread_mutexattr_init (&attr);
+#ifdef NDEBUG
+ pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_DEFAULT);
+#else
+ pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_ERRORCHECK);
+#endif
+ pthread_mutex_init (p_mutex, &attr);
+ pthread_mutexattr_destroy( &attr );
+}
+
+void vlc_mutex_init_recursive( vlc_mutex_t *p_mutex )
+{
+ pthread_mutexattr_t attr;
+
+ pthread_mutexattr_init (&attr);
+ pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_RECURSIVE);
+ pthread_mutex_init (p_mutex, &attr);
+ pthread_mutexattr_destroy( &attr );
+}
+
+
+void vlc_mutex_destroy (vlc_mutex_t *p_mutex)
+{
+ int val = pthread_mutex_destroy( p_mutex );
+ VLC_THREAD_ASSERT ("destroying mutex");
+}
+
+#ifndef NDEBUG
+void vlc_assert_locked (vlc_mutex_t *p_mutex)
+{
+ vlc_assert (pthread_mutex_lock (p_mutex) == EDEADLK);
+}
+#endif
+
+void vlc_mutex_lock (vlc_mutex_t *p_mutex)
+{
+ int val = pthread_mutex_lock( p_mutex );
+ VLC_THREAD_ASSERT ("locking mutex");
+}
+
+int vlc_mutex_trylock (vlc_mutex_t *p_mutex)
+{
+ int val = pthread_mutex_trylock( p_mutex );
+
+ if (val != EBUSY)
+ VLC_THREAD_ASSERT ("locking mutex");
+ return val;
+}
+
+void vlc_mutex_unlock (vlc_mutex_t *p_mutex)
+{
+ int val = pthread_mutex_unlock( p_mutex );
+ VLC_THREAD_ASSERT ("unlocking mutex");
+}
+
+struct vlc_thread
+{
+ pthread_t thread;
+ pthread_cond_t *cond; /// Non-null if thread waiting on cond
+ vlc_mutex_t lock ; /// Protects cond
+
+ void *(*entry)(void*);
+ void *data;
+
+ vlc_atomic_t killable;
+ vlc_atomic_t killed;
+ vlc_atomic_t finished;
+ bool detached;
+};
+
+static __thread struct vlc_thread *thread = NULL;
+
+void vlc_threads_setup (libvlc_int_t *p_libvlc)
+{
+ (void)p_libvlc;
+}
+
+static void *andro_Thread(void *data)
+{
+ thread = data;
+ void *ret = thread->entry(thread->data);
+ if (thread->detached) {
+ /* release thread handle */
+ vlc_mutex_destroy(&thread->lock);
+ free(thread);
+ } else {
+ vlc_atomic_set(&thread->finished, true);
+ /* thread handle will be freed when vlc_join() is called */
+ }
+ return ret;
+}
+
+/* cond */
+
+void vlc_cond_init (vlc_cond_t *p_condvar)
+{
+ if (unlikely(pthread_cond_init (p_condvar, NULL)))
+ abort ();
+}
+
+void vlc_cond_init_daytime (vlc_cond_t *p_condvar)
+{
+ vlc_cond_init(p_condvar);
+}
+
+void vlc_cond_destroy (vlc_cond_t *p_condvar)
+{
+ int val = pthread_cond_destroy( p_condvar );
+ VLC_THREAD_ASSERT ("destroying condition");
+}
+
+void vlc_cond_signal (vlc_cond_t *p_condvar)
+{
+ int val = pthread_cond_signal( p_condvar );
+ VLC_THREAD_ASSERT ("signaling condition variable");
+}
+
+void vlc_cond_broadcast (vlc_cond_t *p_condvar)
+{
+ pthread_cond_broadcast (p_condvar);
+}
+
+void vlc_cond_wait (vlc_cond_t *p_condvar, vlc_mutex_t *p_mutex)
+{
+ if (thread) {
+ vlc_testcancel();
+ vlc_mutex_lock(&thread->lock);
+ thread->cond = p_condvar;
+ vlc_mutex_unlock(&thread->lock);
+ }
+
+ int val = pthread_cond_wait( p_condvar, p_mutex );
+
+ if (thread) {
+ vlc_mutex_lock(&thread->lock);
+ thread->cond = NULL;
+ vlc_mutex_unlock(&thread->lock);
+ vlc_testcancel();
+ }
+
+ VLC_THREAD_ASSERT ("waiting on condition");
+}
+
+int vlc_cond_timedwait (vlc_cond_t *p_condvar, vlc_mutex_t *p_mutex,
+ mtime_t deadline)
+{
+ struct timespec ts = mtime_to_ts (deadline);
+
+ if (thread) {
+ vlc_testcancel();
+ vlc_mutex_lock(&thread->lock);
+ thread->cond = p_condvar;
+ vlc_mutex_unlock(&thread->lock);
+ }
+
+ int val = pthread_cond_timedwait (p_condvar, p_mutex, &ts);
+ if (val != ETIMEDOUT)
+ VLC_THREAD_ASSERT ("timed-waiting on condition");
+
+ if (thread) {
+ vlc_mutex_lock(&thread->lock);
+ thread->cond = NULL;
+ vlc_mutex_unlock(&thread->lock);
+ vlc_testcancel();
+ }
+
+ return val;
+}
+
+/* pthread */
+
+static int vlc_clone_attr (vlc_thread_t *th, pthread_attr_t *attr,
+ void *(*entry) (void *), void *data, int priority)
+{
+ int ret;
+
+ sigset_t oldset;
+ {
+ sigset_t set;
+ sigemptyset (&set);
+ sigdelset (&set, SIGHUP);
+ sigaddset (&set, SIGINT);
+ sigaddset (&set, SIGQUIT);
+ sigaddset (&set, SIGTERM);
+
+ sigaddset (&set, SIGPIPE); /* We don't want this one, really! */
+ pthread_sigmask (SIG_BLOCK, &set, &oldset);
+ }
+
+ (void) priority;
+
+ vlc_thread_t thread = malloc (sizeof (*thread));
+ if (unlikely(thread == NULL)) {
+ if (attr)
+ pthread_attr_destroy(attr);
+ return ENOMEM;
+ }
+
+ vlc_atomic_set(&thread->killable, true);
+ vlc_atomic_set(&thread->killed, false);
+ vlc_atomic_set(&thread->finished, false);
+ int state = PTHREAD_CREATE_JOINABLE;
+ if (attr)
+ pthread_attr_getdetachstate(attr, &state);
+ thread->detached = state == PTHREAD_CREATE_DETACHED;
+ thread->cond = NULL;
+ thread->entry = entry;
+ thread->data = data;
+ vlc_mutex_init(&thread->lock);
+
+ *th = thread;
+ ret = pthread_create (&thread->thread, attr, andro_Thread, thread);
+
+ pthread_sigmask (SIG_SETMASK, &oldset, NULL);
+ if (attr)
+ pthread_attr_destroy (attr);
+ return ret;
+}
+
+int vlc_clone (vlc_thread_t *th, void *(*entry) (void *), void *data,
+ int priority)
+{
+ pthread_attr_t attr;
+
+ pthread_attr_init (&attr);
+ return vlc_clone_attr (th, &attr, entry, data, priority);
+}
+
+void vlc_join (vlc_thread_t handle, void **result)
+{
+ vlc_testcancel();
+ while (!vlc_atomic_get(&handle->finished))
+ msleep(CLOCK_FREQ / 100);
+
+ int val = pthread_join (handle->thread, result);
+ VLC_THREAD_ASSERT ("joining thread");
+ vlc_mutex_destroy(&handle->lock);
+ free(handle);
+}
+
+int vlc_clone_detach (vlc_thread_t *th, void *(*entry) (void *), void *data,
+ int priority)
+{
+ vlc_thread_t dummy;
+ pthread_attr_t attr;
+
+ if (th == NULL)
+ th = &dummy;
+
+ pthread_attr_init (&attr);
+ pthread_attr_setdetachstate (&attr, PTHREAD_CREATE_DETACHED);
+ return vlc_clone_attr (th, &attr, entry, data, priority);
+}
+
+int vlc_set_priority (vlc_thread_t th, int priority)
+{
+ (void) th; (void) priority;
+ return VLC_SUCCESS;
+}
+
+void vlc_cancel (vlc_thread_t thread_id)
+{
+ vlc_atomic_set(&thread_id->killed, true);
+ if (!vlc_atomic_get(&thread_id->killable))
+ return;
+
+ vlc_mutex_lock(&thread_id->lock);
+ vlc_cond_t *cond = thread_id->cond;
+
+ if (cond)
+ pthread_cond_broadcast(cond);
+ vlc_mutex_unlock(&thread_id->lock);
+}
+
+int vlc_savecancel (void)
+{
+ if (!thread) /* not created by VLC, can't be cancelled */
+ return true;
+
+ int oldstate = vlc_atomic_get(&thread->killable);
+ vlc_atomic_set(&thread->killable, false);
+ return oldstate;
+}
+
+void vlc_restorecancel (int state)
+{
+ if (!thread) /* not created by VLC, can't be cancelled */
+ return;
+
+ vlc_atomic_set(&thread->killable, state);
+}
+
+void vlc_testcancel (void)
+{
+ if (!thread) /* not created by VLC, can't be cancelled */
+ return;
+ if (!vlc_atomic_get(&thread->killable))
+ return;
+ if (!vlc_atomic_get(&thread->killed))
+ return;
+
+ vlc_atomic_set(&thread->finished, true);
+ pthread_exit(NULL);
+}
+
+/* threadvar */
+
+int vlc_threadvar_create (vlc_threadvar_t *key, void (*destr) (void *))
+{
+ return pthread_key_create (key, destr);
+}
+
+void vlc_threadvar_delete (vlc_threadvar_t *p_tls)
+{
+ pthread_key_delete (*p_tls);
+}
+
+int vlc_threadvar_set (vlc_threadvar_t key, void *value)
+{
+ return pthread_setspecific (key, value);
+}
+
+void *vlc_threadvar_get (vlc_threadvar_t key)
+{
+ return pthread_getspecific (key);
+}
+
+/* time */
+mtime_t mdate (void)
+{
+ struct timespec ts;
+
+ if (unlikely(clock_gettime (CLOCK_REALTIME, &ts) != 0))
+ abort ();
+
+ return (INT64_C(1000000) * ts.tv_sec) + (ts.tv_nsec / 1000);
+}
+
+#undef mwait
+void mwait (mtime_t deadline)
+{
+ deadline -= mdate ();
+ if (deadline > 0)
+ msleep (deadline);
+}
+
+#undef msleep
+void msleep (mtime_t delay)
+{
+ struct timespec ts = mtime_to_ts (delay);
+
+ vlc_testcancel();
+ for (;;) {
+ /* FIXME: drift */
+ struct timespec t = { 0, 10 * 1000 * 1000 };
+ if (ts.tv_sec <= 0 && t.tv_nsec > ts.tv_nsec)
+ t.tv_nsec = ts.tv_nsec;
+ while (nanosleep (&t, &t) == -1) {
+ vlc_testcancel();
+ vlc_assert (errno == EINTR);
+ }
+
+ ts.tv_nsec -= 10 * 1000 * 1000;
+ if (ts.tv_nsec < 0) {
+ if (--ts.tv_sec < 0)
+ return;
+ ts.tv_nsec += 1000 * 1000 * 1000;
+ }
+ }
+}
+
+/* cpu */
+
+unsigned vlc_GetCPUCount(void)
+{
+ return sysconf(_SC_NPROCESSORS_CONF);
+}
--
1.7.10.4
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