media/libeffects/EffectsFactory.c - platform/frameworks/base - Git at Google

 /*
  * Copyright (C) 2010 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 #define LOG_TAG "EffectsFactory"
 //#define LOG_NDEBUG 0

 #include "EffectsFactory.h"
 #include <string.h>
 #include <stdlib.h>
 #include <dlfcn.h>


 static list_elem_t *gEffectList; // list of effect_entry_t: all currently created effects
 static list_elem_t *gLibraryList; // list of lib_entry_t: all currently loaded libraries
 static pthread_mutex_t gLibLock = PTHREAD_MUTEX_INITIALIZER; // controls access to gLibraryList
 static list_elem_t *gCurLib;    // current library in enumeration process
 static list_elem_t *gCurEffect; // current effect in enumeration process

 static const char * const gEffectLibPath = "/system/lib/soundfx"; // path to built-in effect libraries
 static int gInitDone; // true is global initialization has been preformed

 /////////////////////////////////////////////////
 //      Local functions prototypes
 /////////////////////////////////////////////////

 static int init();
 static int loadLibrary(const char *libPath, int *handle);
 static int unloadLibrary(int handle);
 static int numEffectModules();
 static int findEffect(effect_uuid_t *uuid, lib_entry_t **lib, effect_descriptor_t **desc);
 static void dumpEffectDescriptor(effect_descriptor_t *desc, char *str, size_t len);

 /////////////////////////////////////////////////
 //      Effect Control Interface functions
 /////////////////////////////////////////////////

 int Effect_Process(effect_interface_t self, audio_buffer_t *inBuffer, audio_buffer_t *outBuffer)
 {
     int ret = init();
     if (ret < 0) {
         return ret;
     }
     effect_entry_t *fx = (effect_entry_t *)self;
     pthread_mutex_lock(&gLibLock);
     if (fx->lib == NULL) {
         pthread_mutex_unlock(&gLibLock);
         return -EPIPE;
     }
     pthread_mutex_lock(&fx->lib->lock);
     pthread_mutex_unlock(&gLibLock);

     ret = (*fx->subItfe)->process(fx->subItfe, inBuffer, outBuffer);
     pthread_mutex_unlock(&fx->lib->lock);
     return ret;
 }

 int Effect_Command(effect_interface_t self, int cmdCode, int cmdSize, void *pCmdData, int *replySize, void *pReplyData)
 {
     int ret = init();
     if (ret < 0) {
         return ret;
     }
     effect_entry_t *fx = (effect_entry_t *)self;
     pthread_mutex_lock(&gLibLock);
     if (fx->lib == NULL) {
         pthread_mutex_unlock(&gLibLock);
         return -EPIPE;
     }
     pthread_mutex_lock(&fx->lib->lock);
     pthread_mutex_unlock(&gLibLock);

     ret = (*fx->subItfe)->command(fx->subItfe, cmdCode, cmdSize, pCmdData, replySize, pReplyData);
     pthread_mutex_unlock(&fx->lib->lock);
     return ret;
 }

 const struct effect_interface_s gInterface = {
         Effect_Process,
         Effect_Command
 };

 /////////////////////////////////////////////////
 //      Effect Factory Interface functions
 /////////////////////////////////////////////////

 int EffectQueryNumberEffects(int *pNumEffects)
 {
     int ret = init();
     if (ret < 0) {
         return ret;
     }
     if (pNumEffects == NULL) {
         return -EINVAL;
     }

     pthread_mutex_lock(&gLibLock);
     *pNumEffects = numEffectModules();
     pthread_mutex_unlock(&gLibLock);
     LOGV("EffectQueryNumberEffects(): %d", *pNumEffects);
     return ret;
 }

 int EffectQueryNext(effect_descriptor_t *pDescriptor)
 {
     int ret = init();
     if (ret < 0) {
         return ret;
     }
     if (pDescriptor == NULL) {
         return -EINVAL;
     }

     pthread_mutex_lock(&gLibLock);
     ret = -ENOENT;
     while (gCurLib) {
         if (gCurEffect) {
             memcpy(pDescriptor, gCurEffect->object, sizeof(effect_descriptor_t));
             gCurEffect = gCurEffect->next;
             ret = 0;
             break;
         } else {
             gCurLib = gCurLib->next;
             gCurEffect = ((lib_entry_t *)gCurLib->object)->effects;
         }
     }
     char str[256];
     dumpEffectDescriptor(pDescriptor, str, 256);
     LOGV("EffectQueryNext() desc:%s", str);
     pthread_mutex_unlock(&gLibLock);
     return ret;
 }

 int EffectGetDescriptor(effect_uuid_t *uuid, effect_descriptor_t *pDescriptor)
 {
     lib_entry_t *l = NULL;
     effect_descriptor_t *d = NULL;

     int ret = init();
     if (ret < 0) {
         return ret;
     }
     if (pDescriptor == NULL || uuid == NULL) {
         return -EINVAL;
     }
     pthread_mutex_lock(&gLibLock);
     ret = findEffect(uuid, &l, &d);
     if (ret == 0) {
         memcpy(pDescriptor, d, sizeof(effect_descriptor_t));
     }
     pthread_mutex_unlock(&gLibLock);
     return ret;
 }

 int EffectCreate(effect_uuid_t *uuid, effect_interface_t *pInterface)
 {
     list_elem_t *e = gLibraryList;
     lib_entry_t *l = NULL;
     effect_descriptor_t *d = NULL;
     effect_interface_t itfe;
     effect_entry_t *fx;
     int found = 0;
     int ret;

     if (uuid == NULL || pInterface == NULL) {
         return -EINVAL;
     }

     LOGV("EffectCreate() UUID: %08X-%04X-%04X-%04X-%02X%02X%02X%02X%02X%02X\n",
             uuid->timeLow, uuid->timeMid, uuid->timeHiAndVersion,
             uuid->clockSeq, uuid->node[0], uuid->node[1],uuid->node[2],
             uuid->node[3],uuid->node[4],uuid->node[5]);

     ret = init();

     if (ret < 0) {
         LOGW("EffectCreate() init error: %d", ret);
         return ret;
     }

     pthread_mutex_lock(&gLibLock);

     ret = findEffect(uuid, &l, &d);
     if (ret < 0){
         goto exit;
     }

     // create effect in library
     ret = l->createFx(uuid, &itfe);
     if (ret < 0) {
         LOGW("EffectCreate() library %s: could not create fx %s", l->path, d->name);
         goto exit;
     }

     // add entry to effect list
     fx = (effect_entry_t *)malloc(sizeof(effect_entry_t));
     fx->subItfe = itfe;
     fx->itfe = (struct effect_interface_s *)&gInterface;
     fx->lib = l;

     e = (list_elem_t *)malloc(sizeof(list_elem_t));
     e->object = fx;
     e->next = gEffectList;
     gEffectList = e;

     *pInterface = (effect_interface_t)fx;

     LOGV("EffectCreate() created entry %p with sub itfe %p in library %s", *pInterface, itfe, l->path);

 exit:
     pthread_mutex_unlock(&gLibLock);
     return ret;
 }

 int EffectRelease(effect_interface_t interface)
 {
     effect_entry_t *fx;
     list_elem_t *e1;
     list_elem_t *e2;

     int ret = init();
     if (ret < 0) {
         return ret;
     }

     // remove effect from effect list
     pthread_mutex_lock(&gLibLock);
     e1 = gEffectList;
     e2 = NULL;
     while (e1) {
         if (e1->object == interface) {
             if (e2) {
                 e2->next = e1->next;
             } else {
                 gEffectList = e1->next;
             }
             fx = (effect_entry_t *)e1->object;
             free(e1);
             break;
         }
         e2 = e1;
         e1 = e1->next;
     }
     if (e1 == NULL) {
         ret = -ENOENT;
         goto exit;
     }

     // release effect in library
     if (fx->lib == NULL) {
         LOGW("EffectRelease() fx %p library already unloaded", interface);
     } else {
         pthread_mutex_lock(&fx->lib->lock);
         fx->lib->releaseFx(fx->subItfe);
         pthread_mutex_unlock(&fx->lib->lock);
     }
     free(fx);

 exit:
     pthread_mutex_unlock(&gLibLock);
     return ret;
 }

 int EffectLoadLibrary(const char *libPath, int *handle)
 {
     int ret = init();
     if (ret < 0) {
         return ret;
     }
     if (libPath == NULL) {
         return -EINVAL;
     }
     return loadLibrary(libPath, handle);
 }

 int EffectUnloadLibrary(int handle)
 {
     int ret = init();
     if (ret < 0) {
         return ret;
     }

     return unloadLibrary(handle);
 }

 int EffectIsNullUuid(effect_uuid_t *uuid)
 {
     if (memcmp(uuid, EFFECT_UUID_NULL, sizeof(effect_uuid_t))) {
         return 0;
     }
     return 1;
 }

 /////////////////////////////////////////////////
 //      Local functions
 /////////////////////////////////////////////////

 int init() {
     struct dirent *ent;
     DIR *dir = NULL;
     char libpath[PATH_MAX];
     int hdl;

     if (gInitDone) {
         return 0;
     }

     pthread_mutex_init(&gLibLock, NULL);

     // load built-in libraries
     dir = opendir(gEffectLibPath);
     if (dir == NULL) {
         return -ENODEV;
     }
     while ((ent = readdir(dir)) != NULL) {
         LOGV("init() reading file %s", ent->d_name);
         if ((strlen(ent->d_name) < 3) ||
             strncmp(ent->d_name, "lib", 3) != 0 ||
             strncmp(ent->d_name + strlen(ent->d_name) - 3, ".so", 3) != 0) {
             continue;
         }
         strcpy(libpath, gEffectLibPath);
         strcat(libpath, "/");
         strcat(libpath, ent->d_name);
         if (loadLibrary(libpath, &hdl) < 0) {
             LOGW("init() failed to load library %s",libpath);
         }
     }
     closedir(dir);

     gInitDone = 1;
     LOGV("init() done");
     return 0;
 }


 int loadLibrary(const char *libPath, int *handle)
 {
     void *hdl;
     effect_QueryNumberEffects_t queryNumFx;
     effect_QueryNextEffect_t queryFx;
     effect_CreateEffect_t createFx;
     effect_ReleaseEffect_t releaseFx;
     int numFx;
     int fx;
     int ret;
     list_elem_t *e, *descHead = NULL;
     lib_entry_t *l;

     if (handle == NULL) {
         return -EINVAL;
     }

     *handle = 0;

     hdl = dlopen(libPath, RTLD_NOW);
     if (hdl == 0) {
         LOGW("could open lib %s", libPath);
         return -ENODEV;
     }

     // Check functions availability
     queryNumFx = (effect_QueryNumberEffects_t)dlsym(hdl, "EffectQueryNumberEffects");
     if (queryNumFx == NULL) {
         LOGW("could not get EffectQueryNumberEffects from lib %s", libPath);
         ret = -ENODEV;
         goto error;
     }
     queryFx = (effect_QueryNextEffect_t)dlsym(hdl, "EffectQueryNext");
     if (queryFx == NULL) {
         LOGW("could not get EffectQueryNext from lib %s", libPath);
         ret = -ENODEV;
         goto error;
     }
     createFx = (effect_CreateEffect_t)dlsym(hdl, "EffectCreate");
     if (createFx == NULL) {
         LOGW("could not get EffectCreate from lib %s", libPath);
         ret = -ENODEV;
         goto error;
     }
     releaseFx = (effect_ReleaseEffect_t)dlsym(hdl, "EffectRelease");
     if (releaseFx == NULL) {
         LOGW("could not get EffectRelease from lib %s", libPath);
         ret = -ENODEV;
         goto error;
     }

     // load effect descriptors
     ret = queryNumFx(&numFx);
     if (ret) {
         goto error;
     }

     for (fx = 0; fx < numFx; fx++) {
         effect_descriptor_t *d = malloc(sizeof(effect_descriptor_t));
         if (d == NULL) {
             ret = -ENOMEM;
             goto error;
         }
         ret = queryFx(d);
         if (ret == 0) {
 #if (LOG_NDEBUG==0)
             char s[256];
             dumpEffectDescriptor(d, s, 256);
             LOGV("loadLibrary() read descriptor %p:%s",d, s);
 #endif
             if (d->apiVersion != EFFECT_API_VERSION) {
                 LOGW("Bad API version %04x on lib %s", d->apiVersion, libPath);
                 free(d);
                 continue;
             }
             e = malloc(sizeof(list_elem_t));
             if (e == NULL) {
                 free(d);
                 ret = -ENOMEM;
                 goto error;
             }
             e->object = d;
             e->next = descHead;
             descHead = e;
         } else {
             LOGW("Error querying effect # %d on lib %s", fx, libPath);
         }
     }
     // add entry for library in gLibraryList
     l = malloc(sizeof(lib_entry_t));
     l->handle = hdl;
     strncpy(l->path, libPath, PATH_MAX);
     l->createFx = createFx;
     l->releaseFx = releaseFx;
     l->effects = descHead;
     pthread_mutex_init(&l->lock, NULL);

     e = malloc(sizeof(list_elem_t));
     pthread_mutex_lock(&gLibLock);
     e->next = gLibraryList;
     e->object = l;
     gLibraryList = e;
     pthread_mutex_unlock(&gLibLock);
     LOGV("loadLibrary() linked library %p", l);

     *handle = (int)hdl;

     return 0;

 error:
     LOGW("loadLibrary() error: %d on lib: %s", ret, libPath);
     while (descHead) {
         free(descHead->object);
         e = descHead->next;
         free(descHead);
         descHead = e;;
     }
     dlclose(hdl);
     return ret;
 }

 int unloadLibrary(int handle)
 {
     void *hdl;
     int ret;
     list_elem_t *el1, *el2;
     lib_entry_t *l;
     effect_entry_t *fx;

     pthread_mutex_lock(&gLibLock);
     el1 = gLibraryList;
     el2 = NULL;
     while (el1) {
         l = (lib_entry_t *)el1->object;
         if (handle == (int)l->handle) {
             if (el2) {
                 el2->next = el1->next;
             } else {
                 gLibraryList = el1->next;
             }
             free(el1);
             break;
         }
         el2 = el1;
         el1 = el1->next;
     }
     pthread_mutex_unlock(&gLibLock);
     if (el1 == NULL) {
         return -ENOENT;
     }

     // clear effect descriptor list
     el1 = l->effects;
     while (el1) {
         free(el1->object);
         el2 = el1->next;
         free(el1);
         el1 = el2;
     }

     // disable all effects from this library
     pthread_mutex_lock(&l->lock);
     el1 = gEffectList;
     while (el1) {
         fx = (effect_entry_t *)el1->object;
         if (fx->lib == l) {
             fx->lib = NULL;
         }
         el1 = el1->next;
     }
     pthread_mutex_unlock(&l->lock);

     dlclose(l->handle);
     free(l);
     return 0;
 }


 int numEffectModules() {
     list_elem_t *e = gLibraryList;
     int cnt = 0;

     // Reset pointers for EffectQueryNext()
     gCurLib = e;
     if (e) {
         gCurEffect = ((lib_entry_t *)e->object)->effects;
     }
     while (e) {
         lib_entry_t *l = (lib_entry_t *)e->object;
         list_elem_t *efx = l->effects;
         while (efx) {
             cnt++;
             efx = efx->next;
         }
         e = e->next;
     }
     return cnt;
 }

 int findEffect(effect_uuid_t *uuid, lib_entry_t **lib, effect_descriptor_t **desc)
 {
     list_elem_t *e = gLibraryList;
     lib_entry_t *l = NULL;
     effect_descriptor_t *d = NULL;
     int found = 0;
     int ret = 0;

     while (e && !found) {
         l = (lib_entry_t *)e->object;
         list_elem_t *efx = l->effects;
         while (efx) {
             d = (effect_descriptor_t *)efx->object;
             if (memcmp(&d->uuid, uuid, sizeof(effect_uuid_t)) == 0) {
                 found = 1;
                 break;
             }
             efx = efx->next;
         }
         e = e->next;
     }
     if (!found) {
         LOGV("findEffect() effect not found");
         ret = -ENOENT;
     } else {
         LOGV("findEffect() found effect: %s in lib %s", d->name, l->path);
         *lib = l;
         *desc = d;
     }

     return ret;
 }

 void dumpEffectDescriptor(effect_descriptor_t *desc, char *str, size_t len) {
     char s[256];

     snprintf(str, len, "\nEffect Descriptor %p:\n", desc);
     sprintf(s, "- UUID: %08X-%04X-%04X-%04X-%02X%02X%02X%02X%02X%02X\n",
             desc->uuid.timeLow, desc->uuid.timeMid, desc->uuid.timeHiAndVersion,
             desc->uuid.clockSeq, desc->uuid.node[0], desc->uuid.node[1],desc->uuid.node[2],
             desc->uuid.node[3],desc->uuid.node[4],desc->uuid.node[5]);
     strncat(str, s, len);
     sprintf(s, "- TYPE: %08X-%04X-%04X-%04X-%02X%02X%02X%02X%02X%02X\n",
                 desc->type.timeLow, desc->type.timeMid, desc->type.timeHiAndVersion,
                 desc->type.clockSeq, desc->type.node[0], desc->type.node[1],desc->type.node[2],
                 desc->type.node[3],desc->type.node[4],desc->type.node[5]);
     strncat(str, s, len);
     sprintf(s, "- apiVersion: %04X\n- flags: %08X\n",
             desc->apiVersion, desc->flags);
     strncat(str, s, len);
     sprintf(s, "- name: %s\n", desc->name);
     strncat(str, s, len);
     sprintf(s, "- implementor: %s\n", desc->implementor);
     strncat(str, s, len);
 }
	/*
	* Copyright (C) 2010 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	#define LOG_TAG "EffectsFactory"
	//#define LOG_NDEBUG 0

	#include "EffectsFactory.h"
	#include <string.h>
	#include <stdlib.h>
	#include <dlfcn.h>


	static list_elem_t *gEffectList; // list of effect_entry_t: all currently created effects
	static list_elem_t *gLibraryList; // list of lib_entry_t: all currently loaded libraries
	static pthread_mutex_t gLibLock = PTHREAD_MUTEX_INITIALIZER; // controls access to gLibraryList
	static list_elem_t *gCurLib; // current library in enumeration process
	static list_elem_t *gCurEffect; // current effect in enumeration process

	static const char * const gEffectLibPath = "/system/lib/soundfx"; // path to built-in effect libraries
	static int gInitDone; // true is global initialization has been preformed

	/////////////////////////////////////////////////
	// Local functions prototypes
	/////////////////////////////////////////////////

	static int init();
	static int loadLibrary(const char libPath, int handle);
	static int unloadLibrary(int handle);
	static int numEffectModules();
	static int findEffect(effect_uuid_t uuid, lib_entry_t lib, effect_descriptor_t *desc);
	static void dumpEffectDescriptor(effect_descriptor_t desc, char str, size_t len);

	/////////////////////////////////////////////////
	// Effect Control Interface functions
	/////////////////////////////////////////////////

	int Effect_Process(effect_interface_t self, audio_buffer_t inBuffer, audio_buffer_t outBuffer)
	{
	int ret = init();
	if (ret < 0) {
	return ret;
	}
	effect_entry_t fx = (effect_entry_t )self;
	pthread_mutex_lock(&gLibLock);
	if (fx->lib == NULL) {
	pthread_mutex_unlock(&gLibLock);
	return -EPIPE;
	}
	pthread_mutex_lock(&fx->lib->lock);
	pthread_mutex_unlock(&gLibLock);

	ret = (*fx->subItfe)->process(fx->subItfe, inBuffer, outBuffer);
	pthread_mutex_unlock(&fx->lib->lock);
	return ret;
	}

	int Effect_Command(effect_interface_t self, int cmdCode, int cmdSize, void pCmdData, int replySize, void *pReplyData)
	{
	int ret = init();
	if (ret < 0) {
	return ret;
	}
	effect_entry_t fx = (effect_entry_t )self;
	pthread_mutex_lock(&gLibLock);
	if (fx->lib == NULL) {
	pthread_mutex_unlock(&gLibLock);
	return -EPIPE;
	}
	pthread_mutex_lock(&fx->lib->lock);
	pthread_mutex_unlock(&gLibLock);

	ret = (*fx->subItfe)->command(fx->subItfe, cmdCode, cmdSize, pCmdData, replySize, pReplyData);
	pthread_mutex_unlock(&fx->lib->lock);
	return ret;
	}

	const struct effect_interface_s gInterface = {
	Effect_Process,
	Effect_Command
	};

	/////////////////////////////////////////////////
	// Effect Factory Interface functions
	/////////////////////////////////////////////////

	int EffectQueryNumberEffects(int *pNumEffects)
	{
	int ret = init();
	if (ret < 0) {
	return ret;
	}
	if (pNumEffects == NULL) {
	return -EINVAL;
	}

	pthread_mutex_lock(&gLibLock);
	*pNumEffects = numEffectModules();
	pthread_mutex_unlock(&gLibLock);
	LOGV("EffectQueryNumberEffects(): %d", *pNumEffects);
	return ret;
	}

	int EffectQueryNext(effect_descriptor_t *pDescriptor)
	{
	int ret = init();
	if (ret < 0) {
	return ret;
	}
	if (pDescriptor == NULL) {
	return -EINVAL;
	}

	pthread_mutex_lock(&gLibLock);
	ret = -ENOENT;
	while (gCurLib) {
	if (gCurEffect) {
	memcpy(pDescriptor, gCurEffect->object, sizeof(effect_descriptor_t));
	gCurEffect = gCurEffect->next;
	ret = 0;
	break;
	} else {
	gCurLib = gCurLib->next;
	gCurEffect = ((lib_entry_t *)gCurLib->object)->effects;
	}
	}
	char str[256];
	dumpEffectDescriptor(pDescriptor, str, 256);
	LOGV("EffectQueryNext() desc:%s", str);
	pthread_mutex_unlock(&gLibLock);
	return ret;
	}

	int EffectGetDescriptor(effect_uuid_t uuid, effect_descriptor_t pDescriptor)
	{
	lib_entry_t *l = NULL;
	effect_descriptor_t *d = NULL;

	int ret = init();
	if (ret < 0) {
	return ret;
	}
	if (pDescriptor == NULL \|\| uuid == NULL) {
	return -EINVAL;
	}
	pthread_mutex_lock(&gLibLock);
	ret = findEffect(uuid, &l, &d);
	if (ret == 0) {
	memcpy(pDescriptor, d, sizeof(effect_descriptor_t));
	}
	pthread_mutex_unlock(&gLibLock);
	return ret;
	}

	int EffectCreate(effect_uuid_t uuid, effect_interface_t pInterface)
	{
	list_elem_t *e = gLibraryList;
	lib_entry_t *l = NULL;
	effect_descriptor_t *d = NULL;
	effect_interface_t itfe;
	effect_entry_t *fx;
	int found = 0;
	int ret;

	if (uuid == NULL \|\| pInterface == NULL) {
	return -EINVAL;
	}

	LOGV("EffectCreate() UUID: %08X-%04X-%04X-%04X-%02X%02X%02X%02X%02X%02X\n",
	uuid->timeLow, uuid->timeMid, uuid->timeHiAndVersion,
	uuid->clockSeq, uuid->node[0], uuid->node[1],uuid->node[2],
	uuid->node[3],uuid->node[4],uuid->node[5]);

	ret = init();

	if (ret < 0) {
	LOGW("EffectCreate() init error: %d", ret);
	return ret;
	}

	pthread_mutex_lock(&gLibLock);

	ret = findEffect(uuid, &l, &d);
	if (ret < 0){
	goto exit;
	}

	// create effect in library
	ret = l->createFx(uuid, &itfe);
	if (ret < 0) {
	LOGW("EffectCreate() library %s: could not create fx %s", l->path, d->name);
	goto exit;
	}

	// add entry to effect list
	fx = (effect_entry_t *)malloc(sizeof(effect_entry_t));
	fx->subItfe = itfe;
	fx->itfe = (struct effect_interface_s *)&gInterface;
	fx->lib = l;

	e = (list_elem_t *)malloc(sizeof(list_elem_t));
	e->object = fx;
	e->next = gEffectList;
	gEffectList = e;

	*pInterface = (effect_interface_t)fx;

	LOGV("EffectCreate() created entry %p with sub itfe %p in library %s", *pInterface, itfe, l->path);

	exit:
	pthread_mutex_unlock(&gLibLock);
	return ret;
	}

	int EffectRelease(effect_interface_t interface)
	{
	effect_entry_t *fx;
	list_elem_t *e1;
	list_elem_t *e2;

	int ret = init();
	if (ret < 0) {
	return ret;
	}

	// remove effect from effect list
	pthread_mutex_lock(&gLibLock);
	e1 = gEffectList;
	e2 = NULL;
	while (e1) {
	if (e1->object == interface) {
	if (e2) {
	e2->next = e1->next;
	} else {
	gEffectList = e1->next;
	}
	fx = (effect_entry_t *)e1->object;
	free(e1);
	break;
	}
	e2 = e1;
	e1 = e1->next;
	}
	if (e1 == NULL) {
	ret = -ENOENT;
	goto exit;
	}

	// release effect in library
	if (fx->lib == NULL) {
	LOGW("EffectRelease() fx %p library already unloaded", interface);
	} else {
	pthread_mutex_lock(&fx->lib->lock);
	fx->lib->releaseFx(fx->subItfe);
	pthread_mutex_unlock(&fx->lib->lock);
	}
	free(fx);

	exit:
	pthread_mutex_unlock(&gLibLock);
	return ret;
	}

	int EffectLoadLibrary(const char libPath, int handle)
	{
	int ret = init();
	if (ret < 0) {
	return ret;
	}
	if (libPath == NULL) {
	return -EINVAL;
	}
	return loadLibrary(libPath, handle);
	}

	int EffectUnloadLibrary(int handle)
	{
	int ret = init();
	if (ret < 0) {
	return ret;
	}

	return unloadLibrary(handle);
	}

	int EffectIsNullUuid(effect_uuid_t *uuid)
	{
	if (memcmp(uuid, EFFECT_UUID_NULL, sizeof(effect_uuid_t))) {
	return 0;
	}
	return 1;
	}

	/////////////////////////////////////////////////
	// Local functions
	/////////////////////////////////////////////////

	int init() {
	struct dirent *ent;
	DIR *dir = NULL;
	char libpath[PATH_MAX];
	int hdl;

	if (gInitDone) {
	return 0;
	}

	pthread_mutex_init(&gLibLock, NULL);

	// load built-in libraries
	dir = opendir(gEffectLibPath);
	if (dir == NULL) {
	return -ENODEV;
	}
	while ((ent = readdir(dir)) != NULL) {
	LOGV("init() reading file %s", ent->d_name);
	if ((strlen(ent->d_name) < 3) \|\|
	strncmp(ent->d_name, "lib", 3) != 0 \|\|
	strncmp(ent->d_name + strlen(ent->d_name) - 3, ".so", 3) != 0) {
	continue;
	}
	strcpy(libpath, gEffectLibPath);
	strcat(libpath, "/");
	strcat(libpath, ent->d_name);
	if (loadLibrary(libpath, &hdl) < 0) {
	LOGW("init() failed to load library %s",libpath);
	}
	}
	closedir(dir);

	gInitDone = 1;
	LOGV("init() done");
	return 0;
	}


	int loadLibrary(const char libPath, int handle)
	{
	void *hdl;
	effect_QueryNumberEffects_t queryNumFx;
	effect_QueryNextEffect_t queryFx;
	effect_CreateEffect_t createFx;
	effect_ReleaseEffect_t releaseFx;
	int numFx;
	int fx;
	int ret;
	list_elem_t e, descHead = NULL;
	lib_entry_t *l;

	if (handle == NULL) {
	return -EINVAL;
	}

	*handle = 0;

	hdl = dlopen(libPath, RTLD_NOW);
	if (hdl == 0) {
	LOGW("could open lib %s", libPath);
	return -ENODEV;
	}

	// Check functions availability
	queryNumFx = (effect_QueryNumberEffects_t)dlsym(hdl, "EffectQueryNumberEffects");
	if (queryNumFx == NULL) {
	LOGW("could not get EffectQueryNumberEffects from lib %s", libPath);
	ret = -ENODEV;
	goto error;
	}
	queryFx = (effect_QueryNextEffect_t)dlsym(hdl, "EffectQueryNext");
	if (queryFx == NULL) {
	LOGW("could not get EffectQueryNext from lib %s", libPath);
	ret = -ENODEV;
	goto error;
	}
	createFx = (effect_CreateEffect_t)dlsym(hdl, "EffectCreate");
	if (createFx == NULL) {
	LOGW("could not get EffectCreate from lib %s", libPath);
	ret = -ENODEV;
	goto error;
	}
	releaseFx = (effect_ReleaseEffect_t)dlsym(hdl, "EffectRelease");
	if (releaseFx == NULL) {
	LOGW("could not get EffectRelease from lib %s", libPath);
	ret = -ENODEV;
	goto error;
	}

	// load effect descriptors
	ret = queryNumFx(&numFx);
	if (ret) {
	goto error;
	}

	for (fx = 0; fx < numFx; fx++) {
	effect_descriptor_t *d = malloc(sizeof(effect_descriptor_t));
	if (d == NULL) {
	ret = -ENOMEM;
	goto error;
	}
	ret = queryFx(d);
	if (ret == 0) {
	#if (LOG_NDEBUG==0)
	char s[256];
	dumpEffectDescriptor(d, s, 256);
	LOGV("loadLibrary() read descriptor %p:%s",d, s);
	#endif
	if (d->apiVersion != EFFECT_API_VERSION) {
	LOGW("Bad API version %04x on lib %s", d->apiVersion, libPath);
	free(d);
	continue;
	}
	e = malloc(sizeof(list_elem_t));
	if (e == NULL) {
	free(d);
	ret = -ENOMEM;
	goto error;
	}
	e->object = d;
	e->next = descHead;
	descHead = e;
	} else {
	LOGW("Error querying effect # %d on lib %s", fx, libPath);
	}
	}
	// add entry for library in gLibraryList
	l = malloc(sizeof(lib_entry_t));
	l->handle = hdl;
	strncpy(l->path, libPath, PATH_MAX);
	l->createFx = createFx;
	l->releaseFx = releaseFx;
	l->effects = descHead;
	pthread_mutex_init(&l->lock, NULL);

	e = malloc(sizeof(list_elem_t));
	pthread_mutex_lock(&gLibLock);
	e->next = gLibraryList;
	e->object = l;
	gLibraryList = e;
	pthread_mutex_unlock(&gLibLock);
	LOGV("loadLibrary() linked library %p", l);

	*handle = (int)hdl;

	return 0;

	error:
	LOGW("loadLibrary() error: %d on lib: %s", ret, libPath);
	while (descHead) {
	free(descHead->object);
	e = descHead->next;
	free(descHead);
	descHead = e;;
	}
	dlclose(hdl);
	return ret;
	}

	int unloadLibrary(int handle)
	{
	void *hdl;
	int ret;
	list_elem_t el1, el2;
	lib_entry_t *l;
	effect_entry_t *fx;

	pthread_mutex_lock(&gLibLock);
	el1 = gLibraryList;
	el2 = NULL;
	while (el1) {
	l = (lib_entry_t *)el1->object;
	if (handle == (int)l->handle) {
	if (el2) {
	el2->next = el1->next;
	} else {
	gLibraryList = el1->next;
	}
	free(el1);
	break;
	}
	el2 = el1;
	el1 = el1->next;
	}
	pthread_mutex_unlock(&gLibLock);
	if (el1 == NULL) {
	return -ENOENT;
	}

	// clear effect descriptor list
	el1 = l->effects;
	while (el1) {
	free(el1->object);
	el2 = el1->next;
	free(el1);
	el1 = el2;
	}

	// disable all effects from this library
	pthread_mutex_lock(&l->lock);
	el1 = gEffectList;
	while (el1) {
	fx = (effect_entry_t *)el1->object;
	if (fx->lib == l) {
	fx->lib = NULL;
	}
	el1 = el1->next;
	}
	pthread_mutex_unlock(&l->lock);

	dlclose(l->handle);
	free(l);
	return 0;
	}



	int numEffectModules() {
	list_elem_t *e = gLibraryList;
	int cnt = 0;

	// Reset pointers for EffectQueryNext()
	gCurLib = e;
	if (e) {
	gCurEffect = ((lib_entry_t *)e->object)->effects;
	}
	while (e) {
	lib_entry_t l = (lib_entry_t )e->object;
	list_elem_t *efx = l->effects;
	while (efx) {
	cnt++;
	efx = efx->next;
	}
	e = e->next;
	}
	return cnt;
	}

	int findEffect(effect_uuid_t uuid, lib_entry_t lib, effect_descriptor_t *desc)
	{
	list_elem_t *e = gLibraryList;
	lib_entry_t *l = NULL;
	effect_descriptor_t *d = NULL;
	int found = 0;
	int ret = 0;

	while (e && !found) {
	l = (lib_entry_t *)e->object;
	list_elem_t *efx = l->effects;
	while (efx) {
	d = (effect_descriptor_t *)efx->object;
	if (memcmp(&d->uuid, uuid, sizeof(effect_uuid_t)) == 0) {
	found = 1;
	break;
	}
	efx = efx->next;
	}
	e = e->next;
	}
	if (!found) {
	LOGV("findEffect() effect not found");
	ret = -ENOENT;
	} else {
	LOGV("findEffect() found effect: %s in lib %s", d->name, l->path);
	*lib = l;
	*desc = d;
	}

	return ret;
	}

	void dumpEffectDescriptor(effect_descriptor_t desc, char str, size_t len) {
	char s[256];

	snprintf(str, len, "\nEffect Descriptor %p:\n", desc);
	sprintf(s, "- UUID: %08X-%04X-%04X-%04X-%02X%02X%02X%02X%02X%02X\n",
	desc->uuid.timeLow, desc->uuid.timeMid, desc->uuid.timeHiAndVersion,
	desc->uuid.clockSeq, desc->uuid.node[0], desc->uuid.node[1],desc->uuid.node[2],
	desc->uuid.node[3],desc->uuid.node[4],desc->uuid.node[5]);
	strncat(str, s, len);
	sprintf(s, "- TYPE: %08X-%04X-%04X-%04X-%02X%02X%02X%02X%02X%02X\n",
	desc->type.timeLow, desc->type.timeMid, desc->type.timeHiAndVersion,
	desc->type.clockSeq, desc->type.node[0], desc->type.node[1],desc->type.node[2],
	desc->type.node[3],desc->type.node[4],desc->type.node[5]);
	strncat(str, s, len);
	sprintf(s, "- apiVersion: %04X\n- flags: %08X\n",
	desc->apiVersion, desc->flags);
	strncat(str, s, len);
	sprintf(s, "- name: %s\n", desc->name);
	strncat(str, s, len);
	sprintf(s, "- implementor: %s\n", desc->implementor);
	strncat(str, s, len);
	}