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Issue 1842653006: Update //third_party/protobuf to version 3. (Closed) Base URL: https://chromium.googlesource.com/chromium/src.git@master
Patch Set: merge Created 4 years, 8 months ago
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1 // Protocol Buffers - Google's data interchange format
2 // Copyright 2008 Google Inc. All rights reserved.
3 // https://developers.google.com/protocol-buffers/
4 //
5 // Redistribution and use in source and binary forms, with or without
6 // modification, are permitted provided that the following conditions are
7 // met:
8 //
9 // * Redistributions of source code must retain the above copyright
10 // notice, this list of conditions and the following disclaimer.
11 // * Redistributions in binary form must reproduce the above
12 // copyright notice, this list of conditions and the following disclaimer
13 // in the documentation and/or other materials provided with the
14 // distribution.
15 // * Neither the name of Google Inc. nor the names of its
16 // contributors may be used to endorse or promote products derived from
17 // this software without specific prior written permission.
18 //
19 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30
31 /**
32 * @fileoverview This file contains helper code used by jspb.utils to
33 * handle 64-bit integer conversion to/from strings.
34 *
35 * @author cfallin@google.com (Chris Fallin)
36 *
37 * TODO(haberman): move this to javascript/closure/math?
38 */
39
40 goog.provide('jspb.arith.Int64');
41 goog.provide('jspb.arith.UInt64');
42
43 /**
44 * UInt64 implements some 64-bit arithmetic routines necessary for properly
45 * handling 64-bit integer fields. It implements lossless integer arithmetic on
46 * top of JavaScript's number type, which has only 53 bits of precision, by
47 * representing 64-bit integers as two 32-bit halves.
48 *
49 * @param {number} lo The low 32 bits.
50 * @param {number} hi The high 32 bits.
51 * @constructor
52 */
53 jspb.arith.UInt64 = function(lo, hi) {
54 /**
55 * The low 32 bits.
56 * @public {number}
57 */
58 this.lo = lo;
59 /**
60 * The high 32 bits.
61 * @public {number}
62 */
63 this.hi = hi;
64 };
65
66
67 /**
68 * Compare two 64-bit numbers. Returns -1 if the first is
69 * less, +1 if the first is greater, or 0 if both are equal.
70 * @param {!jspb.arith.UInt64} other
71 * @return {number}
72 */
73 jspb.arith.UInt64.prototype.cmp = function(other) {
74 if (this.hi < other.hi || (this.hi == other.hi && this.lo < other.lo)) {
75 return -1;
76 } else if (this.hi == other.hi && this.lo == other.lo) {
77 return 0;
78 } else {
79 return 1;
80 }
81 };
82
83
84 /**
85 * Right-shift this number by one bit.
86 * @return {!jspb.arith.UInt64}
87 */
88 jspb.arith.UInt64.prototype.rightShift = function() {
89 var hi = this.hi >>> 1;
90 var lo = (this.lo >>> 1) | ((this.hi & 1) << 31);
91 return new jspb.arith.UInt64(lo >>> 0, hi >>> 0);
92 };
93
94
95 /**
96 * Left-shift this number by one bit.
97 * @return {!jspb.arith.UInt64}
98 */
99 jspb.arith.UInt64.prototype.leftShift = function() {
100 var lo = this.lo << 1;
101 var hi = (this.hi << 1) | (this.lo >>> 31);
102 return new jspb.arith.UInt64(lo >>> 0, hi >>> 0);
103 };
104
105
106 /**
107 * Test the MSB.
108 * @return {boolean}
109 */
110 jspb.arith.UInt64.prototype.msb = function() {
111 return !!(this.hi & 0x80000000);
112 };
113
114
115 /**
116 * Test the LSB.
117 * @return {boolean}
118 */
119 jspb.arith.UInt64.prototype.lsb = function() {
120 return !!(this.lo & 1);
121 };
122
123
124 /**
125 * Test whether this number is zero.
126 * @return {boolean}
127 */
128 jspb.arith.UInt64.prototype.zero = function() {
129 return this.lo == 0 && this.hi == 0;
130 };
131
132
133 /**
134 * Add two 64-bit numbers to produce a 64-bit number.
135 * @param {!jspb.arith.UInt64} other
136 * @return {!jspb.arith.UInt64}
137 */
138 jspb.arith.UInt64.prototype.add = function(other) {
139 var lo = ((this.lo + other.lo) & 0xffffffff) >>> 0;
140 var hi =
141 (((this.hi + other.hi) & 0xffffffff) >>> 0) +
142 (((this.lo + other.lo) >= 0x100000000) ? 1 : 0);
143 return new jspb.arith.UInt64(lo >>> 0, hi >>> 0);
144 };
145
146
147 /**
148 * Subtract two 64-bit numbers to produce a 64-bit number.
149 * @param {!jspb.arith.UInt64} other
150 * @return {!jspb.arith.UInt64}
151 */
152 jspb.arith.UInt64.prototype.sub = function(other) {
153 var lo = ((this.lo - other.lo) & 0xffffffff) >>> 0;
154 var hi =
155 (((this.hi - other.hi) & 0xffffffff) >>> 0) -
156 (((this.lo - other.lo) < 0) ? 1 : 0);
157 return new jspb.arith.UInt64(lo >>> 0, hi >>> 0);
158 };
159
160
161 /**
162 * Multiply two 32-bit numbers to produce a 64-bit number.
163 * @param {number} a The first integer: must be in [0, 2^32-1).
164 * @param {number} b The second integer: must be in [0, 2^32-1).
165 * @return {!jspb.arith.UInt64}
166 */
167 jspb.arith.UInt64.mul32x32 = function(a, b) {
168 // Directly multiplying two 32-bit numbers may produce up to 64 bits of
169 // precision, thus losing precision because of the 53-bit mantissa of
170 // JavaScript numbers. So we multiply with 16-bit digits (radix 65536)
171 // instead.
172 var aLow = (a & 0xffff);
173 var aHigh = (a >>> 16);
174 var bLow = (b & 0xffff);
175 var bHigh = (b >>> 16);
176 var productLow =
177 // 32-bit result, result bits 0-31, take all 32 bits
178 (aLow * bLow) +
179 // 32-bit result, result bits 16-47, take bottom 16 as our top 16
180 ((aLow * bHigh) & 0xffff) * 0x10000 +
181 // 32-bit result, result bits 16-47, take bottom 16 as our top 16
182 ((aHigh * bLow) & 0xffff) * 0x10000;
183 var productHigh =
184 // 32-bit result, result bits 32-63, take all 32 bits
185 (aHigh * bHigh) +
186 // 32-bit result, result bits 16-47, take top 16 as our bottom 16
187 ((aLow * bHigh) >>> 16) +
188 // 32-bit result, result bits 16-47, take top 16 as our bottom 16
189 ((aHigh * bLow) >>> 16);
190
191 // Carry. Note that we actually have up to *two* carries due to addition of
192 // three terms.
193 while (productLow >= 0x100000000) {
194 productLow -= 0x100000000;
195 productHigh += 1;
196 }
197
198 return new jspb.arith.UInt64(productLow >>> 0, productHigh >>> 0);
199 };
200
201
202 /**
203 * Multiply this number by a 32-bit number, producing a 96-bit number, then
204 * truncate the top 32 bits.
205 * @param {number} a The multiplier.
206 * @return {!jspb.arith.UInt64}
207 */
208 jspb.arith.UInt64.prototype.mul = function(a) {
209 // Produce two parts: at bits 0-63, and 32-95.
210 var lo = jspb.arith.UInt64.mul32x32(this.lo, a);
211 var hi = jspb.arith.UInt64.mul32x32(this.hi, a);
212 // Left-shift hi by 32 bits, truncating its top bits. The parts will then be
213 // aligned for addition.
214 hi.hi = hi.lo;
215 hi.lo = 0;
216 return lo.add(hi);
217 };
218
219
220 /**
221 * Divide a 64-bit number by a 32-bit number to produce a
222 * 64-bit quotient and a 32-bit remainder.
223 * @param {number} _divisor
224 * @return {Array.<jspb.arith.UInt64>} array of [quotient, remainder],
225 * unless divisor is 0, in which case an empty array is returned.
226 */
227 jspb.arith.UInt64.prototype.div = function(_divisor) {
228 if (_divisor == 0) {
229 return [];
230 }
231
232 // We perform long division using a radix-2 algorithm, for simplicity (i.e.,
233 // one bit at a time). TODO: optimize to a radix-2^32 algorithm, taking care
234 // to get the variable shifts right.
235 var quotient = new jspb.arith.UInt64(0, 0);
236 var remainder = new jspb.arith.UInt64(this.lo, this.hi);
237 var divisor = new jspb.arith.UInt64(_divisor, 0);
238 var unit = new jspb.arith.UInt64(1, 0);
239
240 // Left-shift the divisor and unit until the high bit of divisor is set.
241 while (!divisor.msb()) {
242 divisor = divisor.leftShift();
243 unit = unit.leftShift();
244 }
245
246 // Perform long division one bit at a time.
247 while (!unit.zero()) {
248 // If divisor < remainder, add unit to quotient and subtract divisor from
249 // remainder.
250 if (divisor.cmp(remainder) <= 0) {
251 quotient = quotient.add(unit);
252 remainder = remainder.sub(divisor);
253 }
254 // Right-shift the divisor and unit.
255 divisor = divisor.rightShift();
256 unit = unit.rightShift();
257 }
258
259 return [quotient, remainder];
260 };
261
262
263 /**
264 * Convert a 64-bit number to a string.
265 * @return {string}
266 * @override
267 */
268 jspb.arith.UInt64.prototype.toString = function() {
269 var result = '';
270 var num = this;
271 while (!num.zero()) {
272 var divResult = num.div(10);
273 var quotient = divResult[0], remainder = divResult[1];
274 result = remainder.lo + result;
275 num = quotient;
276 }
277 if (result == '') {
278 result = '0';
279 }
280 return result;
281 };
282
283
284 /**
285 * Parse a string into a 64-bit number. Returns `null` on a parse error.
286 * @param {string} s
287 * @return {?jspb.arith.UInt64}
288 */
289 jspb.arith.UInt64.fromString = function(s) {
290 var result = new jspb.arith.UInt64(0, 0);
291 // optimization: reuse this instance for each digit.
292 var digit64 = new jspb.arith.UInt64(0, 0);
293 for (var i = 0; i < s.length; i++) {
294 if (s[i] < '0' || s[i] > '9') {
295 return null;
296 }
297 var digit = parseInt(s[i], 10);
298 digit64.lo = digit;
299 result = result.mul(10).add(digit64);
300 }
301 return result;
302 };
303
304
305 /**
306 * Make a copy of the uint64.
307 * @return {!jspb.arith.UInt64}
308 */
309 jspb.arith.UInt64.prototype.clone = function() {
310 return new jspb.arith.UInt64(this.lo, this.hi);
311 };
312
313
314 /**
315 * Int64 is like UInt64, but modifies string conversions to interpret the stored
316 * 64-bit value as a twos-complement-signed integer. It does *not* support the
317 * full range of operations that UInt64 does: only add, subtract, and string
318 * conversions.
319 *
320 * N.B. that multiply and divide routines are *NOT* supported. They will throw
321 * exceptions. (They are not necessary to implement string conversions, which
322 * are the only operations we really need in jspb.)
323 *
324 * @param {number} lo The low 32 bits.
325 * @param {number} hi The high 32 bits.
326 * @constructor
327 */
328 jspb.arith.Int64 = function(lo, hi) {
329 /**
330 * The low 32 bits.
331 * @public {number}
332 */
333 this.lo = lo;
334 /**
335 * The high 32 bits.
336 * @public {number}
337 */
338 this.hi = hi;
339 };
340
341
342 /**
343 * Add two 64-bit numbers to produce a 64-bit number.
344 * @param {!jspb.arith.Int64} other
345 * @return {!jspb.arith.Int64}
346 */
347 jspb.arith.Int64.prototype.add = function(other) {
348 var lo = ((this.lo + other.lo) & 0xffffffff) >>> 0;
349 var hi =
350 (((this.hi + other.hi) & 0xffffffff) >>> 0) +
351 (((this.lo + other.lo) >= 0x100000000) ? 1 : 0);
352 return new jspb.arith.Int64(lo >>> 0, hi >>> 0);
353 };
354
355
356 /**
357 * Subtract two 64-bit numbers to produce a 64-bit number.
358 * @param {!jspb.arith.Int64} other
359 * @return {!jspb.arith.Int64}
360 */
361 jspb.arith.Int64.prototype.sub = function(other) {
362 var lo = ((this.lo - other.lo) & 0xffffffff) >>> 0;
363 var hi =
364 (((this.hi - other.hi) & 0xffffffff) >>> 0) -
365 (((this.lo - other.lo) < 0) ? 1 : 0);
366 return new jspb.arith.Int64(lo >>> 0, hi >>> 0);
367 };
368
369
370 /**
371 * Make a copy of the int64.
372 * @return {!jspb.arith.Int64}
373 */
374 jspb.arith.Int64.prototype.clone = function() {
375 return new jspb.arith.Int64(this.lo, this.hi);
376 };
377
378
379 /**
380 * Convert a 64-bit number to a string.
381 * @return {string}
382 * @override
383 */
384 jspb.arith.Int64.prototype.toString = function() {
385 // If the number is negative, find its twos-complement inverse.
386 var sign = (this.hi & 0x80000000) != 0;
387 var num = new jspb.arith.UInt64(this.lo, this.hi);
388 if (sign) {
389 num = new jspb.arith.UInt64(0, 0).sub(num);
390 }
391 return (sign ? '-' : '') + num.toString();
392 };
393
394
395 /**
396 * Parse a string into a 64-bit number. Returns `null` on a parse error.
397 * @param {string} s
398 * @return {?jspb.arith.Int64}
399 */
400 jspb.arith.Int64.fromString = function(s) {
401 var hasNegative = (s.length > 0 && s[0] == '-');
402 if (hasNegative) {
403 s = s.substring(1);
404 }
405 var num = jspb.arith.UInt64.fromString(s);
406 if (num === null) {
407 return null;
408 }
409 if (hasNegative) {
410 num = new jspb.arith.UInt64(0, 0).sub(num);
411 }
412 return new jspb.arith.Int64(num.lo, num.hi);
413 };
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