diff options
Diffstat (limited to 'intl/icu/source/i18n/erarules.cpp')
| -rw-r--r-- | intl/icu/source/i18n/erarules.cpp | 326 |
1 files changed, 326 insertions, 0 deletions
diff --git a/intl/icu/source/i18n/erarules.cpp b/intl/icu/source/i18n/erarules.cpp new file mode 100644 index 0000000000..65405bb84a --- /dev/null +++ b/intl/icu/source/i18n/erarules.cpp @@ -0,0 +1,326 @@ +// © 2018 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html + +#include <utility> + +#include "unicode/utypes.h" + +#if !UCONFIG_NO_FORMATTING + +#include <stdlib.h> +#include "unicode/ucal.h" +#include "unicode/ures.h" +#include "unicode/ustring.h" +#include "unicode/timezone.h" +#include "cmemory.h" +#include "cstring.h" +#include "erarules.h" +#include "gregoimp.h" +#include "uassert.h" + +U_NAMESPACE_BEGIN + +static const int32_t MAX_ENCODED_START_YEAR = 32767; +static const int32_t MIN_ENCODED_START_YEAR = -32768; +static const int32_t MIN_ENCODED_START = -2147483391; // encodeDate(MIN_ENCODED_START_YEAR, 1, 1, ...); + +static const int32_t YEAR_MASK = 0xFFFF0000; +static const int32_t MONTH_MASK = 0x0000FF00; +static const int32_t DAY_MASK = 0x000000FF; + +static const int32_t MAX_INT32 = 0x7FFFFFFF; +static const int32_t MIN_INT32 = 0xFFFFFFFF; + +static const char16_t VAL_FALSE[] = {0x66, 0x61, 0x6c, 0x73, 0x65}; // "false" +static const char16_t VAL_FALSE_LEN = 5; + +static UBool isSet(int startDate) { + return startDate != 0; +} + +static UBool isValidRuleStartDate(int32_t year, int32_t month, int32_t day) { + return year >= MIN_ENCODED_START_YEAR && year <= MAX_ENCODED_START_YEAR + && month >= 1 && month <= 12 && day >=1 && day <= 31; +} + +/** + * Encode year/month/date to a single integer. + * year is high 16 bits (-32768 to 32767), month is + * next 8 bits and day of month is last 8 bits. + * + * @param year year + * @param month month (1-base) + * @param day day of month + * @return an encoded date. + */ +static int32_t encodeDate(int32_t year, int32_t month, int32_t day) { + return (int32_t)((uint32_t)year << 16) | month << 8 | day; +} + +static void decodeDate(int32_t encodedDate, int32_t (&fields)[3]) { + if (encodedDate == MIN_ENCODED_START) { + fields[0] = MIN_INT32; + fields[1] = 1; + fields[2] = 1; + } else { + fields[0] = (encodedDate & YEAR_MASK) >> 16; + fields[1] = (encodedDate & MONTH_MASK) >> 8; + fields[2] = encodedDate & DAY_MASK; + } +} + +/** + * Compare an encoded date with another date specified by year/month/day. + * @param encoded An encoded date + * @param year Year of another date + * @param month Month of another date + * @param day Day of another date + * @return -1 when encoded date is earlier, 0 when two dates are same, + * and 1 when encoded date is later. + */ +static int32_t compareEncodedDateWithYMD(int encoded, int year, int month, int day) { + if (year < MIN_ENCODED_START_YEAR) { + if (encoded == MIN_ENCODED_START) { + if (year > MIN_INT32 || month > 1 || day > 1) { + return -1; + } + return 0; + } else { + return 1; + } + } else if (year > MAX_ENCODED_START_YEAR) { + return -1; + } else { + int tmp = encodeDate(year, month, day); + if (encoded < tmp) { + return -1; + } else if (encoded == tmp) { + return 0; + } else { + return 1; + } + } +} + +EraRules::EraRules(LocalMemory<int32_t>& eraStartDates, int32_t numEras) + : numEras(numEras) { + startDates = std::move(eraStartDates); + initCurrentEra(); +} + +EraRules::~EraRules() { +} + +EraRules* EraRules::createInstance(const char *calType, UBool includeTentativeEra, UErrorCode& status) { + if(U_FAILURE(status)) { + return nullptr; + } + LocalUResourceBundlePointer rb(ures_openDirect(nullptr, "supplementalData", &status)); + ures_getByKey(rb.getAlias(), "calendarData", rb.getAlias(), &status); + ures_getByKey(rb.getAlias(), calType, rb.getAlias(), &status); + ures_getByKey(rb.getAlias(), "eras", rb.getAlias(), &status); + + if (U_FAILURE(status)) { + return nullptr; + } + + int32_t numEras = ures_getSize(rb.getAlias()); + int32_t firstTentativeIdx = MAX_INT32; + + LocalMemory<int32_t> startDates(static_cast<int32_t *>(uprv_malloc(numEras * sizeof(int32_t)))); + if (startDates.isNull()) { + status = U_MEMORY_ALLOCATION_ERROR; + return nullptr; + } + uprv_memset(startDates.getAlias(), 0 , numEras * sizeof(int32_t)); + + while (ures_hasNext(rb.getAlias())) { + LocalUResourceBundlePointer eraRuleRes(ures_getNextResource(rb.getAlias(), nullptr, &status)); + if (U_FAILURE(status)) { + return nullptr; + } + const char *eraIdxStr = ures_getKey(eraRuleRes.getAlias()); + char *endp; + int32_t eraIdx = (int32_t)strtol(eraIdxStr, &endp, 10); + if ((size_t)(endp - eraIdxStr) != uprv_strlen(eraIdxStr)) { + status = U_INVALID_FORMAT_ERROR; + return nullptr; + } + if (eraIdx < 0 || eraIdx >= numEras) { + status = U_INVALID_FORMAT_ERROR; + return nullptr; + } + if (isSet(startDates[eraIdx])) { + // start date of the index was already set + status = U_INVALID_FORMAT_ERROR; + return nullptr; + } + + UBool hasName = true; + UBool hasEnd = true; + int32_t len; + while (ures_hasNext(eraRuleRes.getAlias())) { + LocalUResourceBundlePointer res(ures_getNextResource(eraRuleRes.getAlias(), nullptr, &status)); + if (U_FAILURE(status)) { + return nullptr; + } + const char *key = ures_getKey(res.getAlias()); + if (uprv_strcmp(key, "start") == 0) { + const int32_t *fields = ures_getIntVector(res.getAlias(), &len, &status); + if (U_FAILURE(status)) { + return nullptr; + } + if (len != 3 || !isValidRuleStartDate(fields[0], fields[1], fields[2])) { + status = U_INVALID_FORMAT_ERROR; + return nullptr; + } + startDates[eraIdx] = encodeDate(fields[0], fields[1], fields[2]); + } else if (uprv_strcmp(key, "named") == 0) { + const char16_t *val = ures_getString(res.getAlias(), &len, &status); + if (u_strncmp(val, VAL_FALSE, VAL_FALSE_LEN) == 0) { + hasName = false; + } + } else if (uprv_strcmp(key, "end") == 0) { + hasEnd = true; + } + } + + if (isSet(startDates[eraIdx])) { + if (hasEnd) { + // This implementation assumes either start or end is available, not both. + // For now, just ignore the end rule. + } + } else { + if (hasEnd) { + if (eraIdx != 0) { + // This implementation does not support end only rule for eras other than + // the first one. + status = U_INVALID_FORMAT_ERROR; + return nullptr; + } + U_ASSERT(eraIdx == 0); + startDates[eraIdx] = MIN_ENCODED_START; + } else { + status = U_INVALID_FORMAT_ERROR; + return nullptr; + } + } + + if (hasName) { + if (eraIdx >= firstTentativeIdx) { + status = U_INVALID_FORMAT_ERROR; + return nullptr; + } + } else { + if (eraIdx < firstTentativeIdx) { + firstTentativeIdx = eraIdx; + } + } + } + + EraRules *result; + if (firstTentativeIdx < MAX_INT32 && !includeTentativeEra) { + result = new EraRules(startDates, firstTentativeIdx); + } else { + result = new EraRules(startDates, numEras); + } + + if (result == nullptr) { + status = U_MEMORY_ALLOCATION_ERROR; + } + return result; +} + +void EraRules::getStartDate(int32_t eraIdx, int32_t (&fields)[3], UErrorCode& status) const { + if(U_FAILURE(status)) { + return; + } + if (eraIdx < 0 || eraIdx >= numEras) { + status = U_ILLEGAL_ARGUMENT_ERROR; + return; + } + decodeDate(startDates[eraIdx], fields); +} + +int32_t EraRules::getStartYear(int32_t eraIdx, UErrorCode& status) const { + int year = MAX_INT32; // bogus value + if(U_FAILURE(status)) { + return year; + } + if (eraIdx < 0 || eraIdx >= numEras) { + status = U_ILLEGAL_ARGUMENT_ERROR; + return year; + } + int fields[3]; + decodeDate(startDates[eraIdx], fields); + year = fields[0]; + + return year; +} + +int32_t EraRules::getEraIndex(int32_t year, int32_t month, int32_t day, UErrorCode& status) const { + if(U_FAILURE(status)) { + return -1; + } + + if (month < 1 || month > 12 || day < 1 || day > 31) { + status = U_ILLEGAL_ARGUMENT_ERROR; + return -1; + } + int32_t high = numEras; // last index + 1 + int32_t low; + + // Short circuit for recent years. Most modern computations will + // occur in the last few eras. + if (compareEncodedDateWithYMD(startDates[getCurrentEraIndex()], year, month, day) <= 0) { + low = getCurrentEraIndex(); + } else { + low = 0; + } + + // Do binary search + while (low < high - 1) { + int i = (low + high) / 2; + if (compareEncodedDateWithYMD(startDates[i], year, month, day) <= 0) { + low = i; + } else { + high = i; + } + } + return low; +} + +void EraRules::initCurrentEra() { + // Compute local wall time in millis using ICU's default time zone. + UErrorCode ec = U_ZERO_ERROR; + UDate localMillis = ucal_getNow(); + + int32_t rawOffset, dstOffset; + TimeZone* zone = TimeZone::createDefault(); + // If we failed to create the default time zone, we are in a bad state and don't + // really have many options. Carry on using UTC millis as a fallback. + if (zone != nullptr) { + zone->getOffset(localMillis, false, rawOffset, dstOffset, ec); + delete zone; + localMillis += (rawOffset + dstOffset); + } + + int year, month0, dom, dow, doy, mid; + Grego::timeToFields(localMillis, year, month0, dom, dow, doy, mid); + int currentEncodedDate = encodeDate(year, month0 + 1 /* changes to 1-base */, dom); + int eraIdx = numEras - 1; + while (eraIdx > 0) { + if (currentEncodedDate >= startDates[eraIdx]) { + break; + } + eraIdx--; + } + // Note: current era could be before the first era. + // In this case, this implementation returns the first era index (0). + currentEra = eraIdx; +} + +U_NAMESPACE_END +#endif /* #if !UCONFIG_NO_FORMATTING */ + + |