1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330 |
1
1
1
1
1
320
1
8
8
8
8
8
1
2088
783
1305
1305
1
113
5
5
12
12
12
108
1
73
2
2
2
4
2
71
1
73
1
68
7
61
2
2
59
1
1
1
261
2088
261
2
259
1
67
67
74
66
66
66
66
66
66
1
114
1
14
1
89
89
100
99
99
1
5
1
5
1
62
62
61
68
68
68
1
1
| /*
This file is part of ethereum.js.
ethereum.js is free software: you can redistribute it and/or modify
it under the terms of the GNU Lesser General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
ethereum.js is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public License
along with ethereum.js. If not, see <http://www.gnu.org/licenses/>.
*/
/**
* @file coder.js
* @author Marek Kotewicz <marek@ethdev.com>
* @date 2015
*/
var BigNumber = require('bignumber.js');
var utils = require('../utils/utils');
var f = require('./formatters');
var SolidityParam = require('./param');
/**
* Should be used to check if a type is an array type
*
* @method isArrayType
* @param {String} type
* @return {Bool} true is the type is an array, otherwise false
*/
var isArrayType = function (type) {
return type.slice(-2) === '[]';
};
/**
* SolidityType prototype is used to encode/decode solidity params of certain type
*/
var SolidityType = function (config) {
this._name = config.name;
this._match = config.match;
this._mode = config.mode;
this._inputFormatter = config.inputFormatter;
this._outputFormatter = config.outputFormatter;
};
/**
* Should be used to determine if this SolidityType do match given type
*
* @method isType
* @param {String} name
* @return {Bool} true if type match this SolidityType, otherwise false
*/
SolidityType.prototype.isType = function (name) {
if (this._match === 'strict') {
return this._name === name || (name.indexOf(this._name) === 0 && name.slice(this._name.length) === '[]');
} else Eif (this._match === 'prefix') {
// TODO better type detection!
return name.indexOf(this._name) === 0;
}
};
/**
* Should be used to transform plain param to SolidityParam object
*
* @method formatInput
* @param {Object} param - plain object, or an array of objects
* @param {Bool} arrayType - true if a param should be encoded as an array
* @return {SolidityParam} encoded param wrapped in SolidityParam object
*/
SolidityType.prototype.formatInput = function (param, arrayType) {
if (utils.isArray(param) && arrayType) { // TODO: should fail if this two are not the same
var self = this;
return param.map(function (p) {
return self._inputFormatter(p);
}).reduce(function (acc, current) {
acc.appendArrayElement(current);
return acc;
}, new SolidityParam('', f.formatInputInt(param.length).value));
}
return this._inputFormatter(param);
};
/**
* Should be used to transoform SolidityParam to plain param
*
* @method formatOutput
* @param {SolidityParam} byteArray
* @param {Bool} arrayType - true if a param should be decoded as an array
* @return {Object} plain decoded param
*/
SolidityType.prototype.formatOutput = function (param, arrayType) {
if (arrayType) {
// let's assume, that we solidity will never return long arrays :P
var result = [];
var length = new BigNumber(param.prefix, 16);
for (var i = 0; i < length * 64; i += 64) {
result.push(this._outputFormatter(new SolidityParam(param.suffix.slice(i, i + 64))));
}
return result;
}
return this._outputFormatter(param);
};
/**
* Should be used to check if a type is variadic
*
* @method isVariadicType
* @param {String} type
* @returns {Bool} true if the type is variadic
*/
SolidityType.prototype.isVariadicType = function (type) {
return isArrayType(type) || this._mode === 'bytes';
};
/**
* Should be used to shift param from params group
*
* @method shiftParam
* @param {String} type
* @returns {SolidityParam} shifted param
*/
SolidityType.prototype.shiftParam = function (type, param) {
if (this._mode === 'bytes') {
return param.shiftBytes();
} else if (isArrayType(type)) {
var length = new BigNumber(param.prefix.slice(0, 64), 16);
return param.shiftArray(length);
}
return param.shiftValue();
};
/**
* SolidityCoder prototype should be used to encode/decode solidity params of any type
*/
var SolidityCoder = function (types) {
this._types = types;
};
/**
* This method should be used to transform type to SolidityType
*
* @method _requireType
* @param {String} type
* @returns {SolidityType}
* @throws {Error} throws if no matching type is found
*/
SolidityCoder.prototype._requireType = function (type) {
var solidityType = this._types.filter(function (t) {
return t.isType(type);
})[0];
if (!solidityType) {
throw Error('invalid solidity type!: ' + type);
}
return solidityType;
};
/**
* Should be used to transform plain bytes to SolidityParam object
*
* @method _bytesToParam
* @param {Array} types of params
* @param {String} bytes to be transformed to SolidityParam
* @return {SolidityParam} SolidityParam for this group of params
*/
SolidityCoder.prototype._bytesToParam = function (types, bytes) {
var self = this;
var prefixTypes = types.reduce(function (acc, type) {
return self._requireType(type).isVariadicType(type) ? acc + 1 : acc;
}, 0);
var valueTypes = types.length - prefixTypes;
var prefix = bytes.slice(0, prefixTypes * 64);
bytes = bytes.slice(prefixTypes * 64);
var value = bytes.slice(0, valueTypes * 64);
var suffix = bytes.slice(valueTypes * 64);
return new SolidityParam(value, prefix, suffix);
};
/**
* Should be used to transform plain param of given type to SolidityParam
*
* @method _formatInput
* @param {String} type of param
* @param {Object} plain param
* @return {SolidityParam}
*/
SolidityCoder.prototype._formatInput = function (type, param) {
return this._requireType(type).formatInput(param, isArrayType(type));
};
/**
* Should be used to encode plain param
*
* @method encodeParam
* @param {String} type
* @param {Object} plain param
* @return {String} encoded plain param
*/
SolidityCoder.prototype.encodeParam = function (type, param) {
return this._formatInput(type, param).encode();
};
/**
* Should be used to encode list of params
*
* @method encodeParams
* @param {Array} types
* @param {Array} params
* @return {String} encoded list of params
*/
SolidityCoder.prototype.encodeParams = function (types, params) {
var self = this;
return types.map(function (type, index) {
return self._formatInput(type, params[index]);
}).reduce(function (acc, solidityParam) {
acc.append(solidityParam);
return acc;
}, new SolidityParam()).encode();
};
/**
* Should be used to transform SolidityParam to plain param
*
* @method _formatOutput
* @param {String} type
* @param {SolidityParam} param
* @return {Object} plain param
*/
SolidityCoder.prototype._formatOutput = function (type, param) {
return this._requireType(type).formatOutput(param, isArrayType(type));
};
/**
* Should be used to decode bytes to plain param
*
* @method decodeParam
* @param {String} type
* @param {String} bytes
* @return {Object} plain param
*/
SolidityCoder.prototype.decodeParam = function (type, bytes) {
return this._formatOutput(type, this._bytesToParam([type], bytes));
};
/**
* Should be used to decode list of params
*
* @method decodeParam
* @param {Array} types
* @param {String} bytes
* @return {Array} array of plain params
*/
SolidityCoder.prototype.decodeParams = function (types, bytes) {
var self = this;
var param = this._bytesToParam(types, bytes);
return types.map(function (type) {
var solidityType = self._requireType(type);
var p = solidityType.shiftParam(type, param);
return solidityType.formatOutput(p, isArrayType(type));
});
};
var coder = new SolidityCoder([
new SolidityType({
name: 'address',
match: 'strict',
mode: 'value',
inputFormatter: f.formatInputInt,
outputFormatter: f.formatOutputAddress
}),
new SolidityType({
name: 'bool',
match: 'strict',
mode: 'value',
inputFormatter: f.formatInputBool,
outputFormatter: f.formatOutputBool
}),
new SolidityType({
name: 'int',
match: 'prefix',
mode: 'value',
inputFormatter: f.formatInputInt,
outputFormatter: f.formatOutputInt,
}),
new SolidityType({
name: 'uint',
match: 'prefix',
mode: 'value',
inputFormatter: f.formatInputInt,
outputFormatter: f.formatOutputUInt
}),
new SolidityType({
name: 'bytes',
match: 'strict',
mode: 'bytes',
inputFormatter: f.formatInputDynamicBytes,
outputFormatter: f.formatOutputDynamicBytes
}),
new SolidityType({
name: 'bytes',
match: 'prefix',
mode: 'value',
inputFormatter: f.formatInputBytes,
outputFormatter: f.formatOutputBytes
}),
new SolidityType({
name: 'real',
match: 'prefix',
mode: 'value',
inputFormatter: f.formatInputReal,
outputFormatter: f.formatOutputReal
}),
new SolidityType({
name: 'ureal',
match: 'prefix',
mode: 'value',
inputFormatter: f.formatInputReal,
outputFormatter: f.formatOutputUReal
})
]);
module.exports = coder;
|