├── .gitattributes ├── .gitignore ├── .gitmodules ├── LICENSE ├── Makefile ├── README.md └── src ├── medianizer.sol └── medianizer.t.sol /.gitattributes: -------------------------------------------------------------------------------- 1 | *.sol linguist-language=Solidity -------------------------------------------------------------------------------- /.gitignore: -------------------------------------------------------------------------------- 1 | /out 2 | /build 3 | -------------------------------------------------------------------------------- /.gitmodules: -------------------------------------------------------------------------------- 1 | [submodule "lib/ds-test"] 2 | path = lib/ds-test 3 | url = https://github.com/dapphub/ds-test 4 | [submodule "lib/ds-value"] 5 | path = lib/ds-value 6 | url = https://github.com/dapphub/ds-value 7 | -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | GNU GENERAL PUBLIC LICENSE 2 | Version 3, 29 June 2007 3 | 4 | Copyright (C) 2017 Maker Ecosystem Growth Holdings, INC. 5 | 6 | Preamble 7 | 8 | The GNU General Public License is a free, copyleft license for 9 | software and other kinds of works. 10 | 11 | The licenses for most software and other practical works are designed 12 | to take away your freedom to share and change the works. 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If not, see . 647 | 648 | Also add information on how to contact you by electronic and paper mail. 649 | 650 | If the program does terminal interaction, make it output a short 651 | notice like this when it starts in an interactive mode: 652 | 653 | Copyright (C) 654 | This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 655 | This is free software, and you are welcome to redistribute it 656 | under certain conditions; type `show c' for details. 657 | 658 | The hypothetical commands `show w' and `show c' should show the appropriate 659 | parts of the General Public License. Of course, your program's commands 660 | might be different; for a GUI interface, you would use an "about box". 661 | 662 | You should also get your employer (if you work as a programmer) or school, 663 | if any, to sign a "copyright disclaimer" for the program, if necessary. 664 | For more information on this, and how to apply and follow the GNU GPL, see 665 | . 666 | 667 | The GNU General Public License does not permit incorporating your program 668 | into proprietary programs. If your program is a subroutine library, you 669 | may consider it more useful to permit linking proprietary applications with 670 | the library. If this is what you want to do, use the GNU Lesser General 671 | Public License instead of this License. But first, please read 672 | . 673 | -------------------------------------------------------------------------------- /Makefile: -------------------------------------------------------------------------------- 1 | all :; dapp build 2 | clean :; dapp clean 3 | test :; dapp test 4 | deploy :; dapp create Medianizer 5 | -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/makerdao/medianizer/a950187add87536716c43474ceb634f728b8eb12/README.md -------------------------------------------------------------------------------- /src/medianizer.sol: -------------------------------------------------------------------------------- 1 | pragma solidity ^0.4.24; 2 | 3 | import "ds-value/value.sol"; 4 | 5 | contract Medianizer is DSThing { 6 | event LogValue(bytes32 val); 7 | 8 | uint128 val; 9 | bool public has; 10 | 11 | mapping (bytes12 => address) public values; 12 | mapping (address => bytes12) public indexes; 13 | bytes12 public next = 0x1; 14 | uint96 public min = 0x1; 15 | 16 | function set(address wat) public auth { 17 | bytes12 nextId = bytes12(uint96(next) + 1); 18 | require(nextId != 0x0); 19 | this.set(next, wat); 20 | next = nextId; 21 | } 22 | 23 | function set(bytes12 pos, address wat) public note auth { 24 | require(pos != 0x0); 25 | require(wat == 0 || indexes[wat] == 0); 26 | 27 | indexes[values[pos]] = 0x0; // Making sure to remove a possible existing address in that position 28 | 29 | if (wat != 0) { 30 | indexes[wat] = pos; 31 | } 32 | 33 | values[pos] = wat; 34 | } 35 | 36 | function setMin(uint96 min_) public note auth { 37 | require(min_ != 0x0); 38 | min = min_; 39 | } 40 | 41 | function setNext(bytes12 next_) public note auth { 42 | require(next_ != 0x0); 43 | next = next_; 44 | } 45 | 46 | function unset(bytes12 pos) public auth { 47 | this.set(pos, 0); 48 | } 49 | 50 | function unset(address wat) public auth { 51 | this.set(indexes[wat], 0); 52 | } 53 | 54 | function void() external auth { 55 | has = false; 56 | // TODO: don't allow poke 57 | } 58 | 59 | function poke() external { 60 | (bytes32 val_, bool has_) = compute(); 61 | val = uint128(val_); 62 | has = has_; 63 | emit LogValue(val_); 64 | } 65 | 66 | function peek() external view returns (bytes32, bool) { 67 | return (bytes32(val), has); 68 | } 69 | 70 | function read() external view returns (bytes32) { 71 | require(has); 72 | return bytes32(val); 73 | } 74 | 75 | function compute() public view returns (bytes32, bool) { 76 | bytes32[] memory wuts = new bytes32[](uint96(next) - 1); 77 | uint96 ctr = 0; 78 | for (uint96 i = 1; i < uint96(next); i++) { 79 | if (values[bytes12(i)] != 0) { 80 | bytes32 wut; 81 | bool wuz; 82 | (wut, wuz) = DSValue(values[bytes12(i)]).peek(); 83 | if (wuz) { 84 | if (ctr == 0 || wut >= wuts[ctr - 1]) { 85 | wuts[ctr] = wut; 86 | } else { 87 | uint96 j = 0; 88 | while (wut >= wuts[j]) { 89 | j++; 90 | } 91 | for (uint96 k = ctr; k > j; k--) { 92 | wuts[k] = wuts[k - 1]; 93 | } 94 | wuts[j] = wut; 95 | } 96 | ctr++; 97 | } 98 | } 99 | } 100 | 101 | if (ctr < min) { 102 | return (bytes32(val), false); 103 | } 104 | 105 | bytes32 value; 106 | if (ctr % 2 == 0) { 107 | uint128 val1 = uint128(wuts[(ctr / 2) - 1]); 108 | uint128 val2 = uint128(wuts[ctr / 2]); 109 | value = bytes32(wdiv(add(val1, val2), 2 ether)); 110 | } else { 111 | value = wuts[(ctr - 1) / 2]; 112 | } 113 | 114 | return (value, true); 115 | } 116 | 117 | } 118 | -------------------------------------------------------------------------------- /src/medianizer.t.sol: -------------------------------------------------------------------------------- 1 | pragma solidity ^0.4.24; 2 | 3 | import "ds-test/test.sol"; 4 | import "ds-value/value.sol"; 5 | 6 | import "./medianizer.sol"; 7 | 8 | contract FakePerson { 9 | Medianizer m; 10 | 11 | constructor(Medianizer m_) public { 12 | m = m_; 13 | } 14 | 15 | function set(address wat) public { 16 | m.set(wat); 17 | } 18 | 19 | function set(bytes12 pos, address wat) public { 20 | m.set(pos, wat); 21 | } 22 | 23 | function unset(bytes12 pos) public { 24 | m.unset(pos); 25 | } 26 | 27 | function unset(address wat) public { 28 | m.unset(wat); 29 | } 30 | } 31 | 32 | 33 | contract Test is DSTest { 34 | Medianizer m; 35 | DSValue c1; 36 | DSValue c2; 37 | DSValue c3; 38 | DSValue c4; 39 | DSValue c5; 40 | 41 | function setUp() public { 42 | m = new Medianizer(); 43 | 44 | c1 = new DSValue(); 45 | c2 = new DSValue(); 46 | c3 = new DSValue(); 47 | c4 = new DSValue(); 48 | c5 = new DSValue(); 49 | 50 | c1.poke(5 ether); 51 | c2.poke(10 ether); 52 | c3.poke(7 ether); 53 | c4.poke(8 ether); 54 | c5.poke(1 ether); 55 | } 56 | 57 | function testNoValues() public { 58 | m.poke(); 59 | 60 | assertHasNoValue(m); 61 | } 62 | 63 | function testOneValue() public { 64 | m.set(c1); 65 | 66 | m.poke(); 67 | 68 | assertHasValue(m, 5 ether); 69 | } 70 | 71 | function testTwoValues() public { 72 | m.set(c1); 73 | m.set(c2); 74 | 75 | m.poke(); 76 | 77 | assertHasValue(m, 7.5 ether); 78 | } 79 | 80 | function testThreeValues() public { 81 | m.set(c1); 82 | m.set(c2); 83 | m.set(c3); 84 | 85 | m.poke(); 86 | 87 | assertHasValue(m, 7 ether); 88 | } 89 | 90 | function testFourValues() public { 91 | m.set(c1); 92 | m.set(c2); 93 | m.set(c3); 94 | m.set(c4); 95 | 96 | m.poke(); 97 | 98 | assertHasValue(m, 7.5 ether); 99 | } 100 | 101 | function testFiveValues() public { 102 | m.set(c1); 103 | m.set(c2); 104 | m.set(c3); 105 | m.set(c4); 106 | m.set(c5); 107 | 108 | m.poke(); 109 | 110 | assertHasValue(m, 7 ether); 111 | } 112 | 113 | function testRearrangeValues() public { 114 | m.set(c1); 115 | m.set(c2); 116 | 117 | m.poke(); 118 | 119 | assertEq(m.next(), bytes12(3)); 120 | assertHasValue(m, 7.5 ether); 121 | 122 | m.unset(bytes12(2)); 123 | m.setNext(2); 124 | 125 | m.poke(); 126 | 127 | assertEq(m.next(), bytes12(2)); 128 | assertHasValue(m, 5 ether); 129 | 130 | m.set(c2); 131 | m.poke(); 132 | 133 | assertEq(m.next(), bytes12(3)); 134 | assertHasValue(m, 7.5 ether); 135 | } 136 | 137 | function testFiveValuesDifferentOrder() public { 138 | m.set(c3); 139 | m.set(c2); 140 | m.set(c5); 141 | m.set(c4); 142 | m.set(c1); 143 | 144 | m.poke(); 145 | 146 | assertHasValue(m, 7 ether); 147 | } 148 | 149 | function testOneOfThreeVoid() public { 150 | m.set(c1); 151 | m.set(c2); 152 | m.set(c3); 153 | 154 | c1.void(); 155 | 156 | m.poke(); 157 | 158 | assertHasValue(m, 8.5 ether); 159 | } 160 | 161 | function testTwoOfThreeVoid() public { 162 | m.set(c1); 163 | m.set(c2); 164 | m.set(c3); 165 | 166 | c1.void(); 167 | c2.void(); 168 | 169 | m.poke(); 170 | 171 | assertHasValue(m, 7 ether); 172 | } 173 | 174 | function testAllThreeVoid() public { 175 | m.set(c1); 176 | m.set(c2); 177 | m.set(c3); 178 | 179 | c1.void(); 180 | c2.void(); 181 | c3.void(); 182 | 183 | m.poke(); 184 | 185 | assertHasNoValue(m); 186 | } 187 | 188 | function testBelowMinimum() public { 189 | m.set(c1); 190 | m.set(c2); 191 | m.set(c3); 192 | 193 | m.setMin(2); 194 | 195 | c1.void(); 196 | c2.void(); 197 | 198 | m.poke(); 199 | 200 | assertHasNoValue(m); 201 | } 202 | 203 | function testEqualToMinimum() public { 204 | m.set(c1); 205 | m.set(c2); 206 | m.set(c3); 207 | 208 | m.setMin(1); 209 | 210 | c1.void(); 211 | c2.void(); 212 | 213 | m.poke(); 214 | 215 | assertHasValue(m, 7 ether); 216 | } 217 | 218 | function testAboveMinimum() public { 219 | m.set(c1); 220 | m.set(c2); 221 | m.set(c3); 222 | 223 | m.setMin(2); 224 | 225 | m.poke(); 226 | 227 | assertHasValue(m, 7 ether); 228 | } 229 | 230 | function testRecursiveMedianizer() public { 231 | Medianizer m2 = new Medianizer(); 232 | 233 | m.set(c1); 234 | m.set(c2); 235 | m.set(c3); 236 | 237 | m2.set(c3); 238 | m2.set(c4); 239 | 240 | m2.poke(); 241 | assertHasValue(m2, 7.5 ether); 242 | 243 | m.set(DSValue(m2)); 244 | 245 | m.poke(); 246 | assertHasValue(m, 7.25 ether); 247 | } 248 | 249 | function testUnsetPos() public { 250 | m.set(c1); 251 | m.set(c2); 252 | m.set(c3); 253 | 254 | m.unset(bytes12(2)); 255 | 256 | m.poke(); 257 | 258 | assertHasValue(m, 6 ether); 259 | } 260 | 261 | function testUnsetWat() public { 262 | m.set(c1); 263 | m.set(c2); 264 | m.set(c3); 265 | 266 | m.unset(c2); 267 | 268 | m.poke(); 269 | 270 | assertHasValue(m, 6 ether); 271 | } 272 | 273 | function testSetPos() public { 274 | m.set(c1); 275 | m.set(c2); 276 | m.set(c3); 277 | 278 | m.set(2, c5); 279 | 280 | m.poke(); 281 | 282 | assertHasValue(m, 5 ether); 283 | } 284 | 285 | function testSetPosAndSetAgain() public { 286 | m.set(c1); 287 | m.set(c2); 288 | m.set(c3); 289 | assertEq(m.indexes(c2), bytes12(2)); 290 | 291 | m.set(2, c5); 292 | assertEq(m.indexes(c2), 0); 293 | 294 | m.set(c2); 295 | m.poke(); 296 | assertHasValue(m, 6 ether); 297 | } 298 | 299 | function testNoValueWhenNoPoke() public { 300 | m.set(c1); 301 | 302 | assertHasNoValue(m); 303 | } 304 | 305 | function testDefaultMinimumIsOne() public { 306 | assertEq(uint(m.min()), uint(1)); 307 | } 308 | 309 | function testFailSetPosZero() public { 310 | m.set(0, c1); 311 | } 312 | 313 | function testFailSetMinZero() public { 314 | m.setMin(0); 315 | } 316 | 317 | function testFailAddingDuplicated() public { 318 | m.set(c1); 319 | m.set(c1); 320 | } 321 | 322 | function testFailSet1Unauthorized() public { 323 | FakePerson p = new FakePerson(m); 324 | p.set(c1); 325 | } 326 | 327 | function testFailSet2Unauthorized() public { 328 | FakePerson p = new FakePerson(m); 329 | p.set(bytes12(1), c1); 330 | } 331 | 332 | function testFailUnset1Unauthorized() public { 333 | m.set(c1); 334 | FakePerson p = new FakePerson(m); 335 | p.unset(c1); 336 | } 337 | 338 | function testFailUnset2Unauthorized() public { 339 | m.set(c1); 340 | FakePerson p = new FakePerson(m); 341 | p.unset(bytes12(1)); 342 | } 343 | 344 | // helper functions 345 | function assertHasNoValue(Medianizer med) internal constant { 346 | bool has; 347 | (, has) = med.peek(); 348 | assert(!has); 349 | } 350 | function assertHasValue(Medianizer med, uint value) internal { 351 | bytes32 res; bool has; 352 | (res, has) = med.peek(); 353 | assert(has); 354 | assertEqDecimal(uint256(res), value, 18); 355 | 356 | bytes32 resRead = med.read(); 357 | assertEqDecimal(uint256(resRead), value, 18); 358 | } 359 | } 360 | --------------------------------------------------------------------------------