system/tools/hidl/CompoundType.h

/*
 * Copyright (C) 2016 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.
 */

#ifndef COMPOUND_TYPE_H_

#define COMPOUND_TYPE_H_

#include "Reference.h"
#include "Scope.h"

#include <string>
#include <vector>

namespace android {

struct CompoundType : public Scope {
    enum Style {
        STYLE_STRUCT,
        STYLE_UNION,
        STYLE_SAFE_UNION,
    };

    CompoundType(Style style, const std::string& localName, const FQName& fullName,
                 const Location& location, Scope* parent);

    Style style() const;

    std::vector<const NamedReference<Type>*> getFields() const;
    void addField(NamedReference<Type>* field);

    bool isCompoundType() const override;

    bool deepCanCheckEquality(std::unordered_set<const Type*>* visited) const override;

    std::string typeName() const override;

    std::vector<const Reference<Type>*> getReferences() const override;

    status_t validate() const override;
    status_t validateUniqueNames() const;
    status_t validateSubTypeNames() const;

    std::string getCppType(StorageMode mode,
                           bool specifyNamespaces) const override;

    std::string getJavaType(bool forInitializer) const override;

    std::string getVtsType() const override;

    void emitReaderWriter(
            Formatter &out,
            const std::string &name,
            const std::string &parcelObj,
            bool parcelObjIsPointer,
            bool isReader,
            ErrorMode mode) const override;

    void emitReaderWriterEmbedded(
            Formatter &out,
            size_t depth,
            const std::string &name,
            const std::string &sanitizedName,
            bool nameIsPointer,
            const std::string &parcelObj,
            bool parcelObjIsPointer,
            bool isReader,
            ErrorMode mode,
            const std::string &parentName,
            const std::string &offsetText) const override;

    void emitJavaReaderWriter(
            Formatter &out,
            const std::string &parcelObj,
            const std::string &argName,
            bool isReader) const override;

    void emitJavaFieldInitializer(
            Formatter &out, const std::string &fieldName) const override;

    void emitJavaFieldDefaultInitialValue(
            Formatter &out, const std::string &declaredFieldName) const override;

    void emitJavaFieldReaderWriter(
            Formatter &out,
            size_t depth,
            const std::string &parcelName,
            const std::string &blobName,
            const std::string &fieldName,
            const std::string &offset,
            bool isReader) const override;

    void emitHidlDefinition(Formatter& out) const override;
    void emitTypeDeclarations(Formatter& out) const override;
    void emitTypeForwardDeclaration(Formatter& out) const override;
    void emitPackageTypeDeclarations(Formatter& out) const override;
    void emitPackageTypeHeaderDefinitions(Formatter& out) const override;
    void emitPackageHwDeclarations(Formatter& out) const override;

    void emitTypeDefinitions(Formatter& out, const std::string& prefix) const override;

    void emitJavaTypeDeclarations(Formatter& out, bool atTopLevel) const override;

    bool needsEmbeddedReadWrite() const override;
    bool resultNeedsDeref() const override;

    void emitVtsTypeDeclarations(Formatter& out) const override;
    void emitVtsAttributeType(Formatter& out) const override;

    bool deepIsJavaCompatible(std::unordered_set<const Type*>* visited) const override;
    bool deepContainsPointer(std::unordered_set<const Type*>* visited) const override;

    void getAlignmentAndSize(size_t *align, size_t *size) const override;

    bool containsInterface() const;
private:

    struct Layout {
        size_t offset;
        size_t align;
        size_t size;

        Layout() : offset(0), align(1), size(0) {}
        static size_t getPad(size_t offset, size_t align);
    };

    struct CompoundLayout {
        // Layout of this entire object including metadata.
        // For struct/union, this is the same as innerStruct.
        Layout overall;
        // Layout of user-specified data
        Layout innerStruct;
        // Layout of discriminator for safe union (otherwise zero)
        Layout discriminator;
    };

    Style mStyle;
    std::vector<NamedReference<Type>*> mFields;

    // only emits the struct body. doesn't emit the last ";\n" from the definition
    void emitInlineHidlDefinition(Formatter& out) const;
    // emits the hidl definition line for a field inside the struct. used by emitHidlDefinition
    void emitFieldHidlDefinition(Formatter& out, const NamedReference<Type>& ref) const;

    void emitLayoutAsserts(Formatter& out, const Layout& localLayout,
                           const std::string& localLayoutName) const;

    void emitInvalidSubTypeNamesError(const std::string& subTypeName,
                                      const Location& location) const;

    void emitSafeUnionTypeDefinitions(Formatter& out) const;
    void emitSafeUnionTypeConstructors(Formatter& out) const;
    void emitSafeUnionTypeDeclarations(Formatter& out) const;
    std::unique_ptr<ScalarType> getUnionDiscriminatorType() const;

    void emitSafeUnionUnknownDiscriminatorError(Formatter& out, const std::string& value,
                                                bool fatal) const;

    void emitSafeUnionAssignDefinition(Formatter& out, const std::string& parameterName,
                                       bool usesMoveSemantics) const;

    CompoundLayout getCompoundAlignmentAndSize() const;
    void emitPaddingZero(Formatter& out, size_t offset, size_t size) const;

    void emitSafeUnionReaderWriterForInterfaces(
            Formatter &out,
            const std::string &name,
            const std::string &parcelObj,
            bool parcelObjIsPointer,
            bool isReader,
            ErrorMode mode) const;

    void emitStructReaderWriter(
            Formatter &out, const std::string &prefix, bool isReader) const;

    DISALLOW_COPY_AND_ASSIGN(CompoundType);
};

}  // namespace android

#endif  // COMPOUND_TYPE_H_