Backport of <https://github.com/unicode-org/icu/commit/b7d08bc04>
~~~
From 71dd84d4ffd6600a70e5bca56a22b957e6642bd4 Mon Sep 17 00:00:00 2001
From: Peter Edberg <pedberg@unicode.org>
Date: Sun, 29 Oct 2017 03:38:05 +0000
Subject: [PATCH] ICU-12504 in ICU4C Persian cal, use int64_t math for one
operation to avoid overflow; add tests in C and J
X-SVN-Rev: 40654
---
icu4c/source/i18n/gregoimp.cpp | 5 +++
icu4c/source/i18n/gregoimp.h | 11 ++++++
icu4c/source/i18n/persncal.cpp | 2 +-
icu4c/source/test/intltest/calregts.cpp | 34 ++++++++++++++++++-
icu4c/source/test/intltest/calregts.h | 1 +
.../test/calendar/CalendarRegressionTest.java | 20 ++++++++++-
6 files changed, 70 insertions(+), 3 deletions(-)
~~~
--- source/i18n/gregoimp.cpp
+++ source/i18n/gregoimp.cpp
@@ -27,6 +27,11 @@ int32_t ClockMath::floorDivide(int32_t numerator, int32_t denominator) {
numerator / denominator : ((numerator + 1) / denominator) - 1;
}
+int64_t ClockMath::floorDivide(int64_t numerator, int64_t denominator) {
+ return (numerator >= 0) ?
+ numerator / denominator : ((numerator + 1) / denominator) - 1;
+}
+
int32_t ClockMath::floorDivide(double numerator, int32_t denominator,
int32_t& remainder) {
double quotient;
--- source/i18n/gregoimp.h
+++ source/i18n/gregoimp.h
@@ -40,6 +40,17 @@ class ClockMath {
*/
static int32_t floorDivide(int32_t numerator, int32_t denominator);
+ /**
+ * Divide two integers, returning the floor of the quotient.
+ * Unlike the built-in division, this is mathematically
+ * well-behaved. E.g., <code>-1/4</code> => 0 but
+ * <code>floorDivide(-1,4)</code> => -1.
+ * @param numerator the numerator
+ * @param denominator a divisor which must be != 0
+ * @return the floor of the quotient
+ */
+ static int64_t floorDivide(int64_t numerator, int64_t denominator);
+
/**
* Divide two numbers, returning the floor of the quotient.
* Unlike the built-in division, this is mathematically
--- source/i18n/persncal.cpp
+++ source/i18n/persncal.cpp
@@ -213,7 +213,7 @@ void PersianCalendar::handleComputeFields(int32_t julianDay, UErrorCode &/*statu
int32_t year, month, dayOfMonth, dayOfYear;
int32_t daysSinceEpoch = julianDay - PERSIAN_EPOCH;
- year = 1 + ClockMath::floorDivide(33 * daysSinceEpoch + 3, 12053);
+ year = 1 + (int32_t)ClockMath::floorDivide(33 * (int64_t)daysSinceEpoch + 3, (int64_t)12053);
int32_t farvardin1 = 365 * (year - 1) + ClockMath::floorDivide(8 * year + 21, 33);
dayOfYear = (daysSinceEpoch - farvardin1); // 0-based
--- source/test/intltest/calregts.cpp
+++ source/test/intltest/calregts.cpp
@@ -12,6 +12,7 @@
#include "calregts.h"
+#include "unicode/calendar.h"
#include "unicode/gregocal.h"
#include "unicode/simpletz.h"
#include "unicode/smpdtfmt.h"
@@ -90,6 +91,7 @@ CalendarRegressionTest::runIndexedTest( int32_t index, UBool exec, const char* &
CASE(48,TestT8596);
CASE(49,Test9019);
CASE(50,TestT9452);
+ CASE(52,TestPersianCalOverflow);
default: name = ""; break;
}
}
@@ -2946,4 +2948,34 @@ void CalendarRegressionTest::TestT9452(void) {
}
}
+/**
+ * @bug ticket 13454
+ */
+void CalendarRegressionTest::TestPersianCalOverflow(void) {
+ const char* localeID = "bs_Cyrl@calendar=persian";
+ UErrorCode status = U_ZERO_ERROR;
+ Calendar* cal = Calendar::createInstance(Locale(localeID), status);
+ if(U_FAILURE(status)) {
+ dataerrln("FAIL: Calendar::createInstance for localeID %s: %s", localeID, u_errorName(status));
+ } else {
+ int32_t maxMonth = cal->getMaximum(UCAL_MONTH);
+ int32_t maxDayOfMonth = cal->getMaximum(UCAL_DATE);
+ int32_t jd, month, dayOfMonth;
+ for (jd = 67023580; jd <= 67023584; jd++) { // year 178171, int32_t overflow if jd >= 67023582
+ status = U_ZERO_ERROR;
+ cal->clear();
+ cal->set(UCAL_JULIAN_DAY, jd);
+ month = cal->get(UCAL_MONTH, status);
+ dayOfMonth = cal->get(UCAL_DATE, status);
+ if ( U_FAILURE(status) ) {
+ errln("FAIL: Calendar->get MONTH/DATE for localeID %s, julianDay %d, status %s\n", localeID, jd, u_errorName(status));
+ } else if (month > maxMonth || dayOfMonth > maxDayOfMonth) {
+ errln("FAIL: localeID %s, julianDay %d; maxMonth %d, got month %d; maxDayOfMonth %d, got dayOfMonth %d\n",
+ localeID, jd, maxMonth, month, maxDayOfMonth, dayOfMonth);
+ }
+ }
+ delete cal;
+ }
+}
+
#endif /* #if !UCONFIG_NO_FORMATTING */
--- source/test/intltest/calregts.h
+++ source/test/intltest/calregts.h
@@ -77,6 +77,7 @@ public:
void TestT8596(void);
void Test9019(void);
void TestT9452(void);
+ void TestPersianCalOverflow(void);
void printdate(GregorianCalendar *cal, const char *string);
void dowTest(UBool lenient) ;