aboutsummaryrefslogtreecommitdiffstats
path: root/contrib/libs/icu/i18n/collationcompare.cpp
blob: d9048afc279699b13f111596d9285e3fafb0ac33 (plain) (blame)
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
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
*******************************************************************************
* Copyright (C) 1996-2015, International Business Machines
* Corporation and others.  All Rights Reserved.
*******************************************************************************
* collationcompare.cpp
*
* created on: 2012feb14 with new and old collation code
* created by: Markus W. Scherer
*/

#include "unicode/utypes.h"

#if !UCONFIG_NO_COLLATION

#include "unicode/ucol.h"
#include "cmemory.h"
#include "collation.h"
#include "collationcompare.h"
#include "collationiterator.h"
#include "collationsettings.h"
#include "uassert.h"

U_NAMESPACE_BEGIN

UCollationResult
CollationCompare::compareUpToQuaternary(CollationIterator &left, CollationIterator &right,
                                        const CollationSettings &settings,
                                        UErrorCode &errorCode) {
    if(U_FAILURE(errorCode)) { return UCOL_EQUAL; }

    int32_t options = settings.options;
    uint32_t variableTop;
    if((options & CollationSettings::ALTERNATE_MASK) == 0) {
        variableTop = 0;
    } else {
        // +1 so that we can use "<" and primary ignorables test out early.
        variableTop = settings.variableTop + 1;
    }
    UBool anyVariable = false;

    // Fetch CEs, compare primaries, store secondary & tertiary weights.
    for(;;) {
        // We fetch CEs until we get a non-ignorable primary or reach the end.
        uint32_t leftPrimary;
        do {
            int64_t ce = left.nextCE(errorCode);
            leftPrimary = (uint32_t)(ce >> 32);
            if(leftPrimary < variableTop && leftPrimary > Collation::MERGE_SEPARATOR_PRIMARY) {
                // Variable CE, shift it to quaternary level.
                // Ignore all following primary ignorables, and shift further variable CEs.
                anyVariable = true;
                do {
                    // Store only the primary of the variable CE.
                    left.setCurrentCE(ce & INT64_C(0xffffffff00000000));
                    for(;;) {
                        ce = left.nextCE(errorCode);
                        leftPrimary = (uint32_t)(ce >> 32);
                        if(leftPrimary == 0) {
                            left.setCurrentCE(0);
                        } else {
                            break;
                        }
                    }
                } while(leftPrimary < variableTop &&
                        leftPrimary > Collation::MERGE_SEPARATOR_PRIMARY);
            }
        } while(leftPrimary == 0);

        uint32_t rightPrimary;
        do {
            int64_t ce = right.nextCE(errorCode);
            rightPrimary = (uint32_t)(ce >> 32);
            if(rightPrimary < variableTop && rightPrimary > Collation::MERGE_SEPARATOR_PRIMARY) {
                // Variable CE, shift it to quaternary level.
                // Ignore all following primary ignorables, and shift further variable CEs.
                anyVariable = true;
                do {
                    // Store only the primary of the variable CE.
                    right.setCurrentCE(ce & INT64_C(0xffffffff00000000));
                    for(;;) {
                        ce = right.nextCE(errorCode);
                        rightPrimary = (uint32_t)(ce >> 32);
                        if(rightPrimary == 0) {
                            right.setCurrentCE(0);
                        } else {
                            break;
                        }
                    }
                } while(rightPrimary < variableTop &&
                        rightPrimary > Collation::MERGE_SEPARATOR_PRIMARY);
            }
        } while(rightPrimary == 0);

        if(leftPrimary != rightPrimary) {
            // Return the primary difference, with script reordering.
            if(settings.hasReordering()) {
                leftPrimary = settings.reorder(leftPrimary);
                rightPrimary = settings.reorder(rightPrimary);
            }
            return (leftPrimary < rightPrimary) ? UCOL_LESS : UCOL_GREATER;
        }
        if(leftPrimary == Collation::NO_CE_PRIMARY) { break; }
    }
    if(U_FAILURE(errorCode)) { return UCOL_EQUAL; }

    // Compare the buffered secondary & tertiary weights.
    // We might skip the secondary level but continue with the case level
    // which is turned on separately.
    if(CollationSettings::getStrength(options) >= UCOL_SECONDARY) {
        if((options & CollationSettings::BACKWARD_SECONDARY) == 0) {
            int32_t leftIndex = 0;
            int32_t rightIndex = 0;
            for(;;) {
                uint32_t leftSecondary;
                do {
                    leftSecondary = ((uint32_t)left.getCE(leftIndex++)) >> 16;
                } while(leftSecondary == 0);

                uint32_t rightSecondary;
                do {
                    rightSecondary = ((uint32_t)right.getCE(rightIndex++)) >> 16;
                } while(rightSecondary == 0);

                if(leftSecondary != rightSecondary) {
                    return (leftSecondary < rightSecondary) ? UCOL_LESS : UCOL_GREATER;
                }
                if(leftSecondary == Collation::NO_CE_WEIGHT16) { break; }
            }
        } else {
            // The backwards secondary level compares secondary weights backwards
            // within segments separated by the merge separator (U+FFFE, weight 02).
            int32_t leftStart = 0;
            int32_t rightStart = 0;
            for(;;) {
                // Find the merge separator or the NO_CE terminator.
                uint32_t p;
                int32_t leftLimit = leftStart;
                while((p = (uint32_t)(left.getCE(leftLimit) >> 32)) >
                            Collation::MERGE_SEPARATOR_PRIMARY ||
                        p == 0) {
                    ++leftLimit;
                }
                int32_t rightLimit = rightStart;
                while((p = (uint32_t)(right.getCE(rightLimit) >> 32)) >
                            Collation::MERGE_SEPARATOR_PRIMARY ||
                        p == 0) {
                    ++rightLimit;
                }

                // Compare the segments.
                int32_t leftIndex = leftLimit;
                int32_t rightIndex = rightLimit;
                for(;;) {
                    int32_t leftSecondary = 0;
                    while(leftSecondary == 0 && leftIndex > leftStart) {
                        leftSecondary = ((uint32_t)left.getCE(--leftIndex)) >> 16;
                    }

                    int32_t rightSecondary = 0;
                    while(rightSecondary == 0 && rightIndex > rightStart) {
                        rightSecondary = ((uint32_t)right.getCE(--rightIndex)) >> 16;
                    }

                    if(leftSecondary != rightSecondary) {
                        return (leftSecondary < rightSecondary) ? UCOL_LESS : UCOL_GREATER;
                    }
                    if(leftSecondary == 0) { break; }
                }

                // Did we reach the end of either string?
                // Both strings have the same number of merge separators,
                // or else there would have been a primary-level difference.
                U_ASSERT(left.getCE(leftLimit) == right.getCE(rightLimit));
                if(p == Collation::NO_CE_PRIMARY) { break; }
                // Skip both merge separators and continue.
                leftStart = leftLimit + 1;
                rightStart = rightLimit + 1;
            }
        }
    }

    if((options & CollationSettings::CASE_LEVEL) != 0) {
        int32_t strength = CollationSettings::getStrength(options);
        int32_t leftIndex = 0;
        int32_t rightIndex = 0;
        for(;;) {
            uint32_t leftCase, leftLower32, rightCase;
            if(strength == UCOL_PRIMARY) {
                // Primary+caseLevel: Ignore case level weights of primary ignorables.
                // Otherwise we would get a-umlaut > a
                // which is not desirable for accent-insensitive sorting.
                // Check for (lower 32 bits) == 0 as well because variable CEs are stored
                // with only primary weights.
                int64_t ce;
                do {
                    ce = left.getCE(leftIndex++);
                    leftCase = (uint32_t)ce;
                } while((uint32_t)(ce >> 32) == 0 || leftCase == 0);
                leftLower32 = leftCase;
                leftCase &= 0xc000;

                do {
                    ce = right.getCE(rightIndex++);
                    rightCase = (uint32_t)ce;
                } while((uint32_t)(ce >> 32) == 0 || rightCase == 0);
                rightCase &= 0xc000;
            } else {
                // Secondary+caseLevel: By analogy with the above,
                // ignore case level weights of secondary ignorables.
                //
                // Note: A tertiary CE has uppercase case bits (0.0.ut)
                // to keep tertiary+caseFirst well-formed.
                //
                // Tertiary+caseLevel: Also ignore case level weights of secondary ignorables.
                // Otherwise a tertiary CE's uppercase would be no greater than
                // a primary/secondary CE's uppercase.
                // (See UCA well-formedness condition 2.)
                // We could construct a special case weight higher than uppercase,
                // but it's simpler to always ignore case weights of secondary ignorables,
                // turning 0.0.ut into 0.0.0.t.
                // (See LDML Collation, Case Parameters.)
                do {
                    leftCase = (uint32_t)left.getCE(leftIndex++);
                } while(leftCase <= 0xffff);
                leftLower32 = leftCase;
                leftCase &= 0xc000;

                do {
                    rightCase = (uint32_t)right.getCE(rightIndex++);
                } while(rightCase <= 0xffff);
                rightCase &= 0xc000;
            }

            // No need to handle NO_CE and MERGE_SEPARATOR specially:
            // There is one case weight for each previous-level weight,
            // so level length differences were handled there.
            if(leftCase != rightCase) {
                if((options & CollationSettings::UPPER_FIRST) == 0) {
                    return (leftCase < rightCase) ? UCOL_LESS : UCOL_GREATER;
                } else {
                    return (leftCase < rightCase) ? UCOL_GREATER : UCOL_LESS;
                }
            }
            if((leftLower32 >> 16) == Collation::NO_CE_WEIGHT16) { break; }
        }
    }
    if(CollationSettings::getStrength(options) <= UCOL_SECONDARY) { return UCOL_EQUAL; }

    uint32_t tertiaryMask = CollationSettings::getTertiaryMask(options);

    int32_t leftIndex = 0;
    int32_t rightIndex = 0;
    uint32_t anyQuaternaries = 0;
    for(;;) {
        uint32_t leftLower32, leftTertiary;
        do {
            leftLower32 = (uint32_t)left.getCE(leftIndex++);
            anyQuaternaries |= leftLower32;
            U_ASSERT((leftLower32 & Collation::ONLY_TERTIARY_MASK) != 0 ||
                     (leftLower32 & 0xc0c0) == 0);
            leftTertiary = leftLower32 & tertiaryMask;
        } while(leftTertiary == 0);

        uint32_t rightLower32, rightTertiary;
        do {
            rightLower32 = (uint32_t)right.getCE(rightIndex++);
            anyQuaternaries |= rightLower32;
            U_ASSERT((rightLower32 & Collation::ONLY_TERTIARY_MASK) != 0 ||
                     (rightLower32 & 0xc0c0) == 0);
            rightTertiary = rightLower32 & tertiaryMask;
        } while(rightTertiary == 0);

        if(leftTertiary != rightTertiary) {
            if(CollationSettings::sortsTertiaryUpperCaseFirst(options)) {
                // Pass through NO_CE and keep real tertiary weights larger than that.
                // Do not change the artificial uppercase weight of a tertiary CE (0.0.ut),
                // to keep tertiary CEs well-formed.
                // Their case+tertiary weights must be greater than those of
                // primary and secondary CEs.
                if(leftTertiary > Collation::NO_CE_WEIGHT16) {
                    if(leftLower32 > 0xffff) {
                        leftTertiary ^= 0xc000;
                    } else {
                        leftTertiary += 0x4000;
                    }
                }
                if(rightTertiary > Collation::NO_CE_WEIGHT16) {
                    if(rightLower32 > 0xffff) {
                        rightTertiary ^= 0xc000;
                    } else {
                        rightTertiary += 0x4000;
                    }
                }
            }
            return (leftTertiary < rightTertiary) ? UCOL_LESS : UCOL_GREATER;
        }
        if(leftTertiary == Collation::NO_CE_WEIGHT16) { break; }
    }
    if(CollationSettings::getStrength(options) <= UCOL_TERTIARY) { return UCOL_EQUAL; }

    if(!anyVariable && (anyQuaternaries & 0xc0) == 0) {
        // If there are no "variable" CEs and no non-zero quaternary weights,
        // then there are no quaternary differences.
        return UCOL_EQUAL;
    }

    leftIndex = 0;
    rightIndex = 0;
    for(;;) {
        uint32_t leftQuaternary;
        do {
            int64_t ce = left.getCE(leftIndex++);
            leftQuaternary = (uint32_t)ce & 0xffff;
            if(leftQuaternary <= Collation::NO_CE_WEIGHT16) {
                // Variable primary or completely ignorable or NO_CE.
                leftQuaternary = (uint32_t)(ce >> 32);
            } else {
                // Regular CE, not tertiary ignorable.
                // Preserve the quaternary weight in bits 7..6.
                leftQuaternary |= 0xffffff3f;
            }
        } while(leftQuaternary == 0);

        uint32_t rightQuaternary;
        do {
            int64_t ce = right.getCE(rightIndex++);
            rightQuaternary = (uint32_t)ce & 0xffff;
            if(rightQuaternary <= Collation::NO_CE_WEIGHT16) {
                // Variable primary or completely ignorable or NO_CE.
                rightQuaternary = (uint32_t)(ce >> 32);
            } else {
                // Regular CE, not tertiary ignorable.
                // Preserve the quaternary weight in bits 7..6.
                rightQuaternary |= 0xffffff3f;
            }
        } while(rightQuaternary == 0);

        if(leftQuaternary != rightQuaternary) {
            // Return the difference, with script reordering.
            if(settings.hasReordering()) {
                leftQuaternary = settings.reorder(leftQuaternary);
                rightQuaternary = settings.reorder(rightQuaternary);
            }
            return (leftQuaternary < rightQuaternary) ? UCOL_LESS : UCOL_GREATER;
        }
        if(leftQuaternary == Collation::NO_CE_PRIMARY) { break; }
    }
    return UCOL_EQUAL;
}

U_NAMESPACE_END

#endif  // !UCONFIG_NO_COLLATION