1/*
2 * Copyright (C) 2016 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#ifndef EXPRESSION_H_
18#define EXPRESSION_H_
19
20#include <android-base/macros.h>
21#include <android-base/logging.h>
22#include <hidl-util/StringHelper.h>
23#include <string>
24
25namespace android {
26
27struct AST;
28struct Define;
29
30struct Expression {
31    Expression() {}
32    virtual ~Expression() {}
33
34    enum Type {
35        S32 = 0, // 0b00
36        S64 = 1, // 0b01
37        U32 = 2, // 0b10
38        U64 = 3, // 0b11
39        UNKNOWN = -1
40    };
41
42    static std::string getTypeDescription(Type type) {
43        switch (type) {
44            case S32: return "S32";
45            case S64: return "S64";
46            case U32: return "U32";
47            case U64: return "U64";
48            case UNKNOWN:
49            default:
50                return "UNKNOWN";
51        }
52    }
53
54    static std::string getTypeName(Type type) {
55        switch (type) {
56            case S32: return "int32_t";
57            case S64: return "int64_t";
58            case U32: return "uint32_t";
59            case U64: return "uint64_t";
60            case UNKNOWN:
61            default:
62                return "/* UNKNOWN */";
63        }
64    }
65
66    static Type integralType(std::string integer);
67    static Type coalesceTypes(Type lhs, Type rhs);
68
69    static Expression *parenthesize(Expression *inner);
70    static Expression *atom(Type type, const std::string &value, bool isId = false);
71    static Expression *unary(std::string op, Expression *rhs);
72    static Expression *binary(Expression *lhs, std::string op, Expression *rhs);
73    static Expression *ternary(Expression *lhs, Expression *mhs, Expression *rhs);
74    static Expression *arraySubscript(std::string id, Expression *subscript);
75    static Expression *functionCall(std::string id, std::vector<Expression *> *args);
76
77    virtual Type getType(const AST &scope) = 0;
78
79    // convert this expression to a string.
80    // atomCase: when it comes to atoms, force identifiers into a certain case.
81    //           numerical values are not affected.
82    virtual std::string toString(StringHelper::Case atomCase = StringHelper::kNoCase) = 0;
83
84private:
85
86    DISALLOW_COPY_AND_ASSIGN(Expression);
87};
88
89}  // namespace android
90
91#endif  // EXPRESSION_H_
92