diff options
Diffstat (limited to 'media/libavextensions/common')
-rw-r--r-- | media/libavextensions/common/AVExtensionsCommon.h | 67 | ||||
-rw-r--r-- | media/libavextensions/common/ExtensionsLoader.hpp | 97 |
2 files changed, 164 insertions, 0 deletions
diff --git a/media/libavextensions/common/AVExtensionsCommon.h b/media/libavextensions/common/AVExtensionsCommon.h new file mode 100644 index 0000000..c39872e --- /dev/null +++ b/media/libavextensions/common/AVExtensionsCommon.h @@ -0,0 +1,67 @@ +/* + * Copyright (c) 2013 - 2015, The Linux Foundation. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials provided + * with the distribution. + * * Neither the name of The Linux Foundation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS + * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR + * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, + * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE + * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN + * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#ifndef _AV_EXTENSIONS_COMMON_H_ +#define _AV_EXTENSIONS_COMMON_H_ + +namespace android { + +typedef void *(*createFunction_t)(void); + +template <typename T> +struct ExtensionsLoader { + + static T *createInstance(const char *createFunctionName); + +private: + static void loadLib(); + static createFunction_t loadCreateFunction(const char *createFunctionName); + static void *mLibHandle; +}; + +/* + * Boiler-plate to declare the class as a singleton (with a static getter) + * which can be loaded (dlopen'd) via ExtensionsLoader + */ +#define DECLARE_LOADABLE_SINGLETON(className) \ +protected: \ + className(); \ + virtual ~className(); \ + static className *sInst; \ +private: \ + className(const className&); \ + className &operator=(className &); \ +public: \ + static className *get() { \ + return sInst; \ + } \ + friend struct ExtensionsLoader<className>; + +} //namespace android + +#endif // _AV_EXTENSIONS_COMMON_H_ diff --git a/media/libavextensions/common/ExtensionsLoader.hpp b/media/libavextensions/common/ExtensionsLoader.hpp new file mode 100644 index 0000000..15728ed --- /dev/null +++ b/media/libavextensions/common/ExtensionsLoader.hpp @@ -0,0 +1,97 @@ +/* + * Copyright (c) 2013 - 2015, The Linux Foundation. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials provided + * with the distribution. + * * Neither the name of The Linux Foundation nor the names of its + * contributors may be used to endorse or promote products derived + * from this software without specific prior written permission. + * + * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT + * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS + * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF + * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR + * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, + * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE + * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN + * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ +#include <dlfcn.h> +#include <common/AVExtensionsCommon.h> +#include <cutils/properties.h> + +namespace android { + +static const char * CUSTOMIZATION_LIB_NAME = "libavenhancements.so"; + +/* + * Create strongly-typed objects of type T + * If the customization library exists and does contain a "named" constructor, + * invoke and create an instance + * Else create the object of type T itself + * + * Contains a static instance to dlopen'd library, But may end up + * opening the library mutiple times. Following snip from dlopen man page is + * reassuring "...Only a single copy of an object file is brought into the + * address space, even if dlopen() is invoked multiple times in reference to + * the file, and even if different pathnames are used to reference the file.." + */ + +template <typename T> +T *ExtensionsLoader<T>::createInstance(const char *createFunctionName) { + (void)createFunctionName; + // create extended object if extensions-lib is available and + // AV_ENHANCEMENTS is enabled +#if ENABLE_AV_ENHANCEMENTS + bool enabled = property_get_bool("media.avenhancements.enabled", false); + if (enabled) { + createFunction_t createFunc = loadCreateFunction(createFunctionName); + if (createFunc) { + return reinterpret_cast<T *>((*createFunc)()); + } + } +#endif + // Else, create the default object + return new T; +} + +template <typename T> +void ExtensionsLoader<T>::loadLib() { + if (!mLibHandle) { + mLibHandle = ::dlopen(CUSTOMIZATION_LIB_NAME, RTLD_LAZY); + if (!mLibHandle) { + ALOGV("%s", dlerror()); + return; + } + ALOGV("Opened %s", CUSTOMIZATION_LIB_NAME); + } +} + +template <typename T> +createFunction_t ExtensionsLoader<T>::loadCreateFunction(const char *createFunctionName) { + loadLib(); + if (!mLibHandle) { + return NULL; + } + createFunction_t func = (createFunction_t)dlsym(mLibHandle, createFunctionName); + if (!func) { + ALOGW("symbol %s not found: %s",createFunctionName, dlerror()); + } + return func; +} + +//static +template <typename T> +void *ExtensionsLoader<T>::mLibHandle = NULL; + +} //namespace android |