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374ca955 1/*
46f4442e 2 **********************************************************************
729e4ab9 3 * Copyright (c) 2003-2008, International Business Machines
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4 * Corporation and others. All Rights Reserved.
5 **********************************************************************
6 * Author: Alan Liu
7 * Created: September 2 2003
8 * Since: ICU 2.8
9 **********************************************************************
10 */
11
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12#include "gregoimp.h"
13
14#if !UCONFIG_NO_FORMATTING
15
16#include "unicode/ucal.h"
17#include "uresimp.h"
18#include "cstring.h"
19#include "uassert.h"
20
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21#if defined(U_DEBUG_CALDATA)
22#include <stdio.h>
23#endif
24
25U_NAMESPACE_BEGIN
26
729e4ab9 27int32_t ClockMath::floorDivide(int32_t numerator, int32_t denominator) {
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28 return (numerator >= 0) ?
29 numerator / denominator : ((numerator + 1) / denominator) - 1;
30}
31
729e4ab9 32int32_t ClockMath::floorDivide(double numerator, int32_t denominator,
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33 int32_t& remainder) {
34 double quotient;
35 quotient = uprv_floor(numerator / denominator);
36 remainder = (int32_t) (numerator - (quotient * denominator));
37 return (int32_t) quotient;
38}
39
729e4ab9 40double ClockMath::floorDivide(double dividend, double divisor,
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41 double& remainder) {
42 // Only designed to work for positive divisors
43 U_ASSERT(divisor > 0);
44 double quotient = floorDivide(dividend, divisor);
45 remainder = dividend - (quotient * divisor);
46 // N.B. For certain large dividends, on certain platforms, there
47 // is a bug such that the quotient is off by one. If you doubt
48 // this to be true, set a breakpoint below and run cintltst.
49 if (remainder < 0 || remainder >= divisor) {
50 // E.g. 6.7317038241449352e+022 / 86400000.0 is wrong on my
51 // machine (too high by one). 4.1792057231752762e+024 /
52 // 86400000.0 is wrong the other way (too low).
53 double q = quotient;
54 quotient += (remainder < 0) ? -1 : +1;
55 if (q == quotient) {
56 // For quotients > ~2^53, we won't be able to add or
57 // subtract one, since the LSB of the mantissa will be >
58 // 2^0; that is, the exponent (base 2) will be larger than
59 // the length, in bits, of the mantissa. In that case, we
60 // can't give a correct answer, so we set the remainder to
61 // zero. This has the desired effect of making extreme
62 // values give back an approximate answer rather than
63 // crashing. For example, UDate values above a ~10^25
64 // might all have a time of midnight.
65 remainder = 0;
66 } else {
67 remainder = dividend - (quotient * divisor);
68 }
69 }
70 U_ASSERT(0 <= remainder && remainder < divisor);
71 return quotient;
72}
73
74const int32_t JULIAN_1_CE = 1721426; // January 1, 1 CE Gregorian
75const int32_t JULIAN_1970_CE = 2440588; // January 1, 1970 CE Gregorian
76
77const int16_t Grego::DAYS_BEFORE[24] =
78 {0,31,59,90,120,151,181,212,243,273,304,334,
79 0,31,60,91,121,152,182,213,244,274,305,335};
80
81const int8_t Grego::MONTH_LENGTH[24] =
82 {31,28,31,30,31,30,31,31,30,31,30,31,
83 31,29,31,30,31,30,31,31,30,31,30,31};
84
85double Grego::fieldsToDay(int32_t year, int32_t month, int32_t dom) {
86
87 int32_t y = year - 1;
88
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89 double julian = 365 * y + ClockMath::floorDivide(y, 4) + (JULIAN_1_CE - 3) + // Julian cal
90 ClockMath::floorDivide(y, 400) - ClockMath::floorDivide(y, 100) + 2 + // => Gregorian cal
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91 DAYS_BEFORE[month + (isLeapYear(year) ? 12 : 0)] + dom; // => month/dom
92
93 return julian - JULIAN_1970_CE; // JD => epoch day
94}
95
96void Grego::dayToFields(double day, int32_t& year, int32_t& month,
97 int32_t& dom, int32_t& dow, int32_t& doy) {
98
99 // Convert from 1970 CE epoch to 1 CE epoch (Gregorian calendar)
100 day += JULIAN_1970_CE - JULIAN_1_CE;
101
102 // Convert from the day number to the multiple radix
103 // representation. We use 400-year, 100-year, and 4-year cycles.
104 // For example, the 4-year cycle has 4 years + 1 leap day; giving
105 // 1461 == 365*4 + 1 days.
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106 int32_t n400 = ClockMath::floorDivide(day, 146097, doy); // 400-year cycle length
107 int32_t n100 = ClockMath::floorDivide(doy, 36524, doy); // 100-year cycle length
108 int32_t n4 = ClockMath::floorDivide(doy, 1461, doy); // 4-year cycle length
109 int32_t n1 = ClockMath::floorDivide(doy, 365, doy);
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110 year = 400*n400 + 100*n100 + 4*n4 + n1;
111 if (n100 == 4 || n1 == 4) {
112 doy = 365; // Dec 31 at end of 4- or 400-year cycle
113 } else {
114 ++year;
115 }
116
117 UBool isLeap = isLeapYear(year);
118
119 // Gregorian day zero is a Monday.
120 dow = (int32_t) uprv_fmod(day + 1, 7);
121 dow += (dow < 0) ? (UCAL_SUNDAY + 7) : UCAL_SUNDAY;
122
123 // Common Julian/Gregorian calculation
124 int32_t correction = 0;
125 int32_t march1 = isLeap ? 60 : 59; // zero-based DOY for March 1
126 if (doy >= march1) {
127 correction = isLeap ? 1 : 2;
128 }
129 month = (12 * (doy + correction) + 6) / 367; // zero-based month
130 dom = doy - DAYS_BEFORE[month + (isLeap ? 12 : 0)] + 1; // one-based DOM
131 doy++; // one-based doy
132}
133
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134void Grego::timeToFields(UDate time, int32_t& year, int32_t& month,
135 int32_t& dom, int32_t& dow, int32_t& doy, int32_t& mid) {
136 double millisInDay;
729e4ab9 137 double day = ClockMath::floorDivide((double)time, (double)U_MILLIS_PER_DAY, millisInDay);
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138 mid = (int32_t)millisInDay;
139 dayToFields(day, year, month, dom, dow, doy);
140}
141
142int32_t Grego::dayOfWeek(double day) {
143 int32_t dow;
729e4ab9 144 ClockMath::floorDivide(day + UCAL_THURSDAY, 7, dow);
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145 return (dow == 0) ? UCAL_SATURDAY : dow;
146}
147
148int32_t Grego::dayOfWeekInMonth(int32_t year, int32_t month, int32_t dom) {
149 int32_t weekInMonth = (dom + 6)/7;
150 if (weekInMonth == 4) {
151 if (dom + 7 > monthLength(year, month)) {
152 weekInMonth = -1;
153 }
154 } else if (weekInMonth == 5) {
155 weekInMonth = -1;
156 }
157 return weekInMonth;
158}
159
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160/* ---- CalendarData ------ */
161
162#define U_CALENDAR_KEY "calendar"
163#define U_GREGORIAN_KEY "gregorian"
164#define U_FORMAT_KEY "format"
165#define U_DEFAULT_KEY "default"
166#define U_CALENDAR_DATA ((char*)0)
167
168
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169// CalendarData::CalendarData(const Locale& loc, UErrorCode& status)
170// : fFillin(NULL), fBundle(NULL), fFallback(NULL) {
171// initData(loc.getBaseName(), (char*) "???", status);
172// }
173
174CalendarData::CalendarData(const Locale& loc, const char *type, UErrorCode& status)
175 : fFillin(NULL), fOtherFillin(NULL), fBundle(NULL), fFallback(NULL) {
176 initData(loc.getBaseName(), type, status);
177}
178
179void CalendarData::initData(const char *locale, const char *type, UErrorCode& status) {
180 fOtherFillin = ures_open(U_CALENDAR_DATA, locale, &status);
181 fFillin = ures_getByKey(fOtherFillin, U_CALENDAR_KEY, fFillin, &status);
182
183 if((type != NULL) &&
184 (*type != '\0') &&
185 (uprv_strcmp(type, U_GREGORIAN_KEY)))
186 {
187 fBundle = ures_getByKeyWithFallback(fFillin, type, NULL, &status);
188 fFallback = ures_getByKeyWithFallback(fFillin, U_GREGORIAN_KEY, NULL, &status);
189
190#if defined (U_DEBUG_CALDATA)
191 fprintf(stderr, "%p: CalendarData(%s, %s, %s) -> main(%p, %s)=%s, fallback(%p, %s)=%s\n",
192 this, locale, type, u_errorName(status), fBundle, type, fBundle?ures_getLocale(fBundle, &status):"",
193 fFallback, U_GREGORIAN_KEY, fFallback?ures_getLocale(fFallback, &status):"");
194#endif
195
196 } else {
197 fBundle = ures_getByKeyWithFallback(fFillin, U_GREGORIAN_KEY, NULL, &status);
198#if defined (U_DEBUG_CALDATA)
199 fprintf(stderr, "%p: CalendarData(%s, %s, %s) -> main(%p, %s)=%s, fallback = NULL\n",
200 this, locale, type, u_errorName(status), fBundle, U_GREGORIAN_KEY, fBundle?ures_getLocale(fBundle, &status):"" );
201#endif
202 }
203}
204
205CalendarData::~CalendarData() {
206 ures_close(fFillin);
207 ures_close(fBundle);
208 ures_close(fFallback);
209 ures_close(fOtherFillin);
210}
211
212UResourceBundle*
213CalendarData::getByKey(const char *key, UErrorCode& status) {
214 if(U_FAILURE(status)) {
215 return NULL;
216 }
217
218 if(fBundle) {
219 fFillin = ures_getByKeyWithFallback(fBundle, key, fFillin, &status);
220#if defined (U_DEBUG_CALDATA)
221 fprintf(stderr, "%p: get %s -> %s - from MAIN %s\n",this, key, u_errorName(status), ures_getLocale(fFillin, &status));
222#endif
223 }
224 if(fFallback && (status == U_MISSING_RESOURCE_ERROR)) {
225 status = U_ZERO_ERROR; // retry with fallback (gregorian)
226 fFillin = ures_getByKeyWithFallback(fFallback, key, fFillin, &status);
227#if defined (U_DEBUG_CALDATA)
228 fprintf(stderr, "%p: get %s -> %s - from FALLBACK %s\n",this, key, u_errorName(status), ures_getLocale(fFillin, &status));
229#endif
230 }
231 return fFillin;
232}
233
234UResourceBundle* CalendarData::getByKey2(const char *key, const char *subKey, UErrorCode& status) {
235 if(U_FAILURE(status)) {
236 return NULL;
237 }
238
239 if(fBundle) {
240#if defined (U_DEBUG_CALDATA)
241 fprintf(stderr, "%p: //\n");
242#endif
243 fFillin = ures_getByKeyWithFallback(fBundle, key, fFillin, &status);
244 fOtherFillin = ures_getByKeyWithFallback(fFillin, U_FORMAT_KEY, fOtherFillin, &status);
245 fFillin = ures_getByKeyWithFallback(fOtherFillin, subKey, fFillin, &status);
246#if defined (U_DEBUG_CALDATA)
247 fprintf(stderr, "%p: get %s/format/%s -> %s - from MAIN %s\n", this, key, subKey, u_errorName(status), ures_getLocale(fFillin, &status));
248#endif
249 }
250 if(fFallback && (status == U_MISSING_RESOURCE_ERROR)) {
251 status = U_ZERO_ERROR; // retry with fallback (gregorian)
252 fFillin = ures_getByKeyWithFallback(fFallback, key, fFillin, &status);
253 fOtherFillin = ures_getByKeyWithFallback(fFillin, U_FORMAT_KEY, fOtherFillin, &status);
254 fFillin = ures_getByKeyWithFallback(fOtherFillin, subKey, fFillin, &status);
255#if defined (U_DEBUG_CALDATA)
256 fprintf(stderr, "%p: get %s/format/%s -> %s - from FALLBACK %s\n",this, key, subKey, u_errorName(status), ures_getLocale(fFillin,&status));
257#endif
258 }
259
260//// handling of 'default' keyword on failure: Commented out for 3.0.
261// if((status == U_MISSING_RESOURCE_ERROR) &&
262// uprv_strcmp(subKey,U_DEFAULT_KEY)) { // avoid recursion
263// #if defined (U_DEBUG_CALDATA)
264// fprintf(stderr, "%p: - attempting fallback -\n", this);
265// fflush(stderr);
266// #endif
267// UErrorCode subStatus = U_ZERO_ERROR;
268// int32_t len;
269// char kwBuf[128] = "";
270// const UChar *kw;
271// /* fFillin = */ getByKey2(key, U_DEFAULT_KEY, subStatus);
272// kw = ures_getString(fFillin, &len, &subStatus);
273// if(len>126) { // too big
274// len = 0;
275// }
276// if(U_SUCCESS(subStatus) && (len>0)) {
277// u_UCharsToChars(kw, kwBuf, len+1);
278// if(*kwBuf && uprv_strcmp(kwBuf,subKey)) {
279// #if defined (U_DEBUG_CALDATA)
280// fprintf(stderr, "%p: trying %s/format/default -> \"%s\"\n",this, key, kwBuf);
281// #endif
282// // now try again with the default
283// status = U_ZERO_ERROR;
284// /* fFillin = */ getByKey2(key, kwBuf, status);
285// }
286// #if defined (U_DEBUG_CALDATA)
287// } else {
288// fprintf(stderr, "%p: could not load %s/format/default - fail out (%s)\n",this, key, kwBuf, u_errorName(status));
289// #endif
290// }
291// }
292
293 return fFillin;
294}
295
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296UResourceBundle* CalendarData::getByKey3(const char *key, const char *contextKey, const char *subKey, UErrorCode& status) {
297 if(U_FAILURE(status)) {
298 return NULL;
299 }
300
301 if(fBundle) {
302#if defined (U_DEBUG_CALDATA)
303 fprintf(stderr, "%p: //\n");
304#endif
305 fFillin = ures_getByKeyWithFallback(fBundle, key, fFillin, &status);
306 fOtherFillin = ures_getByKeyWithFallback(fFillin, contextKey, fOtherFillin, &status);
307 fFillin = ures_getByKeyWithFallback(fOtherFillin, subKey, fFillin, &status);
308#if defined (U_DEBUG_CALDATA)
309 fprintf(stderr, "%p: get %s/%s/%s -> %s - from MAIN %s\n", this, key, contextKey, subKey, u_errorName(status), ures_getLocale(fFillin, &status));
310#endif
311 }
312 if(fFallback && (status == U_MISSING_RESOURCE_ERROR)) {
313 status = U_ZERO_ERROR; // retry with fallback (gregorian)
314 fFillin = ures_getByKeyWithFallback(fFallback, key, fFillin, &status);
315 fOtherFillin = ures_getByKeyWithFallback(fFillin, contextKey, fOtherFillin, &status);
316 fFillin = ures_getByKeyWithFallback(fOtherFillin, subKey, fFillin, &status);
317#if defined (U_DEBUG_CALDATA)
318 fprintf(stderr, "%p: get %s/%s/%s -> %s - from FALLBACK %s\n",this, key, contextKey, subKey, u_errorName(status), ures_getLocale(fFillin,&status));
319#endif
320 }
321
322 return fFillin;
323}
374ca955 324
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325U_NAMESPACE_END
326
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327#endif
328//eof