media/libstagefright/foundation/AMessage.cpp

/*
 * 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.
 */

#include "AMessage.h"

#include "AAtomizer.h"
#include "ADebug.h"
#include "ALooperRoster.h"
#include "AString.h"

namespace android {

AMessage::AMessage(uint32_t what, ALooper::handler_id target)
    : mWhat(what),
      mTarget(target),
      mNumItems(0) {
}

AMessage::~AMessage() {
    clear();
}

void AMessage::setWhat(uint32_t what) {
    mWhat = what;
}

uint32_t AMessage::what() const {
    return mWhat;
}

void AMessage::setTarget(ALooper::handler_id handlerID) {
    mTarget = handlerID;
}

ALooper::handler_id AMessage::target() const {
    return mTarget;
}

void AMessage::clear() {
    for (size_t i = 0; i < mNumItems; ++i) {
        Item *item = &mItems[i];
        freeItem(item);
    }
    mNumItems = 0;
}

void AMessage::freeItem(Item *item) {
    switch (item->mType) {
        case kTypeString:
        {
            delete item->u.stringValue;
            break;
        }

        case kTypeObject:
        case kTypeMessage:
        {
            if (item->u.refValue != NULL) {
                item->u.refValue->decStrong(this);
            }
            break;
        }

        default:
            break;
    }
}

AMessage::Item *AMessage::allocateItem(const char *name) {
    name = AAtomizer::Atomize(name);

    size_t i = 0;
    while (i < mNumItems && mItems[i].mName != name) {
        ++i;
    }

    Item *item;

    if (i < mNumItems) {
        item = &mItems[i];
        freeItem(item);
    } else {
        CHECK(mNumItems < kMaxNumItems);
        i = mNumItems++;
        item = &mItems[i];

        item->mName = name;
    }

    return item;
}

const AMessage::Item *AMessage::findItem(
        const char *name, Type type) const {
    name = AAtomizer::Atomize(name);

    for (size_t i = 0; i < mNumItems; ++i) {
        const Item *item = &mItems[i];

        if (item->mName == name) {
            return item->mType == type ? item : NULL;
        }
    }

    return NULL;
}

#define BASIC_TYPE(NAME,FIELDNAME,TYPENAME)                             \
void AMessage::set##NAME(const char *name, TYPENAME value) {            \
    Item *item = allocateItem(name);                                    \
                                                                        \
    item->mType = kType##NAME;                                          \
    item->u.FIELDNAME = value;                                          \
}                                                                       \
                                                                        \
bool AMessage::find##NAME(const char *name, TYPENAME *value) const {    \
    const Item *item = findItem(name, kType##NAME);                     \
    if (item) {                                                         \
        *value = item->u.FIELDNAME;                                     \
        return true;                                                    \
    }                                                                   \
    return false;                                                       \
}

BASIC_TYPE(Int32,int32Value,int32_t)
BASIC_TYPE(Int64,int64Value,int64_t)
BASIC_TYPE(Size,sizeValue,size_t)
BASIC_TYPE(Float,floatValue,float)
BASIC_TYPE(Double,doubleValue,double)
BASIC_TYPE(Pointer,ptrValue,void *)

#undef BASIC_TYPE

void AMessage::setString(
        const char *name, const char *s, ssize_t len) {
    Item *item = allocateItem(name);
    item->mType = kTypeString;
    item->u.stringValue = new AString(s, len < 0 ? strlen(s) : len);
}

void AMessage::setObject(const char *name, const sp<RefBase> &obj) {
    Item *item = allocateItem(name);
    item->mType = kTypeObject;

    if (obj != NULL) { obj->incStrong(this); }
    item->u.refValue = obj.get();
}

void AMessage::setMessage(const char *name, const sp<AMessage> &obj) {
    Item *item = allocateItem(name);
    item->mType = kTypeMessage;

    if (obj != NULL) { obj->incStrong(this); }
    item->u.refValue = obj.get();
}

bool AMessage::findString(const char *name, AString *value) const {
    const Item *item = findItem(name, kTypeString);
    if (item) {
        *value = *item->u.stringValue;
        return true;
    }
    return false;
}

bool AMessage::findObject(const char *name, sp<RefBase> *obj) const {
    const Item *item = findItem(name, kTypeObject);
    if (item) {
        *obj = item->u.refValue;
        return true;
    }
    return false;
}

bool AMessage::findMessage(const char *name, sp<AMessage> *obj) const {
    const Item *item = findItem(name, kTypeMessage);
    if (item) {
        *obj = static_cast<AMessage *>(item->u.refValue);
        return true;
    }
    return false;
}

void AMessage::post(int64_t delayUs) {
    extern ALooperRoster gLooperRoster;

    gLooperRoster.postMessage(this, delayUs);
}

sp<AMessage> AMessage::dup() const {
    sp<AMessage> msg = new AMessage(mWhat, mTarget);
    msg->mNumItems = mNumItems;

    for (size_t i = 0; i < mNumItems; ++i) {
        const Item *from = &mItems[i];
        Item *to = &msg->mItems[i];

        to->mName = from->mName;
        to->mType = from->mType;

        switch (from->mType) {
            case kTypeString:
            {
                to->u.stringValue =
                    new AString(*from->u.stringValue);
                break;
            }

            case kTypeObject:
            case kTypeMessage:
            {
                to->u.refValue = from->u.refValue;
                to->u.refValue->incStrong(msg.get());
                break;
            }

            default:
            {
                to->u = from->u;
                break;
            }
        }
    }

    return msg;
}

}  // namespace android