FFmpeg/libavcodec/jni.c

/*
 * JNI public API functions
 *
 * Copyright (c) 2015-2016 Matthieu Bouron <matthieu.bouron stupeflix.com>
 *
 * This file is part of FFmpeg.
 *
 * FFmpeg 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.
 *
 * FFmpeg 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 FFmpeg; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include "config.h"

#include <stdlib.h>

#include "libavutil/error.h"
#include "jni.h"

#if CONFIG_JNI
#include <jni.h>
#include <pthread.h>

#include "libavutil/log.h"
#include "ffjni.h"

static void *java_vm;
static void *android_app_ctx;
static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;

int av_jni_set_java_vm(void *vm, void *log_ctx)
{
    int ret = 0;

    pthread_mutex_lock(&lock);
    if (java_vm == NULL) {
        java_vm = vm;
    } else if (java_vm != vm) {
        ret = AVERROR(EINVAL);
        av_log(log_ctx, AV_LOG_ERROR, "A Java virtual machine has already been set");
    }
    pthread_mutex_unlock(&lock);

    return ret;
}

void *av_jni_get_java_vm(void *log_ctx)
{
    void *vm;

    pthread_mutex_lock(&lock);
    vm = java_vm;
    pthread_mutex_unlock(&lock);

    return vm;
}

#else

int av_jni_set_java_vm(void *vm, void *log_ctx)
{
    return AVERROR(ENOSYS);
}

void *av_jni_get_java_vm(void *log_ctx)
{
    return NULL;
}

#endif

#if defined(__ANDROID__)

int av_jni_set_android_app_ctx(void *app_ctx, void *log_ctx)
{
#if CONFIG_JNI
    JNIEnv *env = ff_jni_get_env(log_ctx);
    if (!env)
        return AVERROR(EINVAL);

    jobjectRefType type = (*env)->GetObjectRefType(env, app_ctx);
    if (type != JNIGlobalRefType) {
        av_log(log_ctx, AV_LOG_ERROR, "Application context must be passed as a global reference");
        return AVERROR(EINVAL);
    }

    pthread_mutex_lock(&lock);
    android_app_ctx = app_ctx;
    pthread_mutex_unlock(&lock);

    return 0;
#else
    return AVERROR(ENOSYS);
#endif
}

void *av_jni_get_android_app_ctx(void)
{
#if CONFIG_JNI
    void *ctx;

    pthread_mutex_lock(&lock);
    ctx = android_app_ctx;
    pthread_mutex_unlock(&lock);

    return ctx;
#else
    return NULL;
#endif
}

#endif