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1 // © 2016 and later: Unicode, Inc. and others.
2 // License & terms of use: http://www.unicode.org/copyright.html
3 /*
4 ******************************************************************************
5 *
6 *   Copyright (C) 1997-2016, International Business Machines
7 *   Corporation and others.  All Rights Reserved.
8 *
9 ******************************************************************************
10 *
11 *  FILE NAME : putil.c (previously putil.cpp and ptypes.cpp)
12 *
13 *   Date        Name        Description
14 *   04/14/97    aliu        Creation.
15 *   04/24/97    aliu        Added getDefaultDataDirectory() and
16 *                            getDefaultLocaleID().
17 *   04/28/97    aliu        Rewritten to assume Unix and apply general methods
18 *                            for assumed case.  Non-UNIX platforms must be
19 *                            special-cased.  Rewrote numeric methods dealing
20 *                            with NaN and Infinity to be platform independent
21 *                             over all IEEE 754 platforms.
22 *   05/13/97    aliu        Restored sign of timezone
23 *                            (semantics are hours West of GMT)
24 *   06/16/98    erm         Added IEEE_754 stuff, cleaned up isInfinite, isNan,
25 *                             nextDouble..
26 *   07/22/98    stephen     Added remainder, max, min, trunc
27 *   08/13/98    stephen     Added isNegativeInfinity, isPositiveInfinity
28 *   08/24/98    stephen     Added longBitsFromDouble
29 *   09/08/98    stephen     Minor changes for Mac Port
30 *   03/02/99    stephen     Removed openFile().  Added AS400 support.
31 *                            Fixed EBCDIC tables
32 *   04/15/99    stephen     Converted to C.
33 *   06/28/99    stephen     Removed mutex locking in u_isBigEndian().
34 *   08/04/99    jeffrey R.  Added OS/2 changes
35 *   11/15/99    helena      Integrated S/390 IEEE support.
36 *   04/26/01    Barry N.    OS/400 support for uprv_getDefaultLocaleID
37 *   08/15/01    Steven H.   OS/400 support for uprv_getDefaultCodepage
38 *   01/03/08    Steven L.   Fake Time Support
39 ******************************************************************************
40 */
41 
42 // Defines _XOPEN_SOURCE for access to POSIX functions.
43 // Must be before any other #includes.
44 #include "uposixdefs.h"
45 
46 // First, the platform type. Need this for U_PLATFORM.
47 #include "unicode/platform.h"
48 
49 #if U_PLATFORM == U_PF_MINGW && defined __STRICT_ANSI__
50 /* tzset isn't defined in strict ANSI on MinGW. */
51 #undef __STRICT_ANSI__
52 #endif
53 
54 /*
55  * Cygwin with GCC requires inclusion of time.h after the above disabling strict asci mode statement.
56  */
57 #include <time.h>
58 
59 #if !U_PLATFORM_USES_ONLY_WIN32_API
60 #include <sys/time.h>
61 #endif
62 
63 /* include the rest of the ICU headers */
64 #include "unicode/putil.h"
65 #include "unicode/ustring.h"
66 #include "putilimp.h"
67 #include "uassert.h"
68 #include "umutex.h"
69 #include "cmemory.h"
70 #include "cstring.h"
71 #include "locmap.h"
72 #include "ucln_cmn.h"
73 #include "charstr.h"
74 
75 /* Include standard headers. */
76 #include <stdio.h>
77 #include <stdlib.h>
78 #include <string.h>
79 #include <math.h>
80 #include <locale.h>
81 #include <float.h>
82 
83 #ifndef U_COMMON_IMPLEMENTATION
84 #error U_COMMON_IMPLEMENTATION not set - must be set for all ICU source files in common/ - see https://unicode-org.github.io/icu/userguide/howtouseicu
85 #endif
86 
87 
88 /* include system headers */
89 #if U_PLATFORM_USES_ONLY_WIN32_API
90     /*
91      * TODO: U_PLATFORM_USES_ONLY_WIN32_API includes MinGW.
92      * Should Cygwin be included as well (U_PLATFORM_HAS_WIN32_API)
93      * to use native APIs as much as possible?
94      */
95 #ifndef WIN32_LEAN_AND_MEAN
96 #   define WIN32_LEAN_AND_MEAN
97 #endif
98 #   define VC_EXTRALEAN
99 #   define NOUSER
100 #   define NOSERVICE
101 #   define NOIME
102 #   define NOMCX
103 #   include <windows.h>
104 #   include "unicode/uloc.h"
105 #   include "wintz.h"
106 #elif U_PLATFORM == U_PF_OS400
107 #   include <float.h>
108 #   include <qusec.h>       /* error code structure */
109 #   include <qusrjobi.h>
110 #   include <qliept.h>      /* EPT_CALL macro  - this include must be after all other "QSYSINCs" */
111 #   include <mih/testptr.h> /* For uprv_maximumPtr */
112 #elif U_PLATFORM == U_PF_OS390
113 #   include "unicode/ucnv.h"   /* Needed for UCNV_SWAP_LFNL_OPTION_STRING */
114 #elif U_PLATFORM_IS_DARWIN_BASED || U_PLATFORM_IS_LINUX_BASED || U_PLATFORM == U_PF_BSD || U_PLATFORM == U_PF_SOLARIS
115 #   include <limits.h>
116 #   include <unistd.h>
117 #   if U_PLATFORM == U_PF_SOLARIS
118 #       ifndef _XPG4_2
119 #           define _XPG4_2
120 #       endif
121 #   elif U_PLATFORM == U_PF_ANDROID
122 #       include <sys/system_properties.h>
123 #       include <dlfcn.h>
124 #   endif
125 #elif U_PLATFORM == U_PF_QNX
126 #   include <sys/neutrino.h>
127 #endif
128 
129 
130 /*
131  * Only include langinfo.h if we have a way to get the codeset. If we later
132  * depend on more feature, we can test on U_HAVE_NL_LANGINFO.
133  *
134  */
135 
136 #if U_HAVE_NL_LANGINFO_CODESET
137 #include <langinfo.h>
138 #endif
139 
140 /**
141  * Simple things (presence of functions, etc) should just go in configure.in and be added to
142  * icucfg.h via autoheader.
143  */
144 #if U_PLATFORM_IMPLEMENTS_POSIX
145 #   if U_PLATFORM == U_PF_OS400
146 #    define HAVE_DLFCN_H 0
147 #    define HAVE_DLOPEN 0
148 #   else
149 #   ifndef HAVE_DLFCN_H
150 #    define HAVE_DLFCN_H 1
151 #   endif
152 #   ifndef HAVE_DLOPEN
153 #    define HAVE_DLOPEN 1
154 #   endif
155 #   endif
156 #   ifndef HAVE_GETTIMEOFDAY
157 #    define HAVE_GETTIMEOFDAY 1
158 #   endif
159 #else
160 #   define HAVE_DLFCN_H 0
161 #   define HAVE_DLOPEN 0
162 #   define HAVE_GETTIMEOFDAY 0
163 #endif
164 
165 U_NAMESPACE_USE
166 
167 /* Define the extension for data files, again... */
168 #define DATA_TYPE "dat"
169 
170 /* Leave this copyright notice here! */
171 static const char copyright[] = U_COPYRIGHT_STRING;
172 
173 /* floating point implementations ------------------------------------------- */
174 
175 /* We return QNAN rather than SNAN*/
176 #define SIGN 0x80000000U
177 
178 /* Make it easy to define certain types of constants */
179 typedef union {
180     int64_t i64; /* This must be defined first in order to allow the initialization to work. This is a C89 feature. */
181     double d64;
182 } BitPatternConversion;
183 static const BitPatternConversion gNan = { (int64_t) INT64_C(0x7FF8000000000000) };
184 static const BitPatternConversion gInf = { (int64_t) INT64_C(0x7FF0000000000000) };
185 
186 /*---------------------------------------------------------------------------
187   Platform utilities
188   Our general strategy is to assume we're on a POSIX platform.  Platforms which
189   are non-POSIX must declare themselves so.  The default POSIX implementation
190   will sometimes work for non-POSIX platforms as well (e.g., the NaN-related
191   functions).
192   ---------------------------------------------------------------------------*/
193 
194 #if U_PLATFORM_USES_ONLY_WIN32_API || U_PLATFORM == U_PF_OS400
195 #   undef U_POSIX_LOCALE
196 #else
197 #   define U_POSIX_LOCALE    1
198 #endif
199 
200 /*
201     WARNING! u_topNBytesOfDouble and u_bottomNBytesOfDouble
202     can't be properly optimized by the gcc compiler sometimes (i.e. gcc 3.2).
203 */
204 #if !IEEE_754
205 static char*
u_topNBytesOfDouble(double * d,int n)206 u_topNBytesOfDouble(double* d, int n)
207 {
208 #if U_IS_BIG_ENDIAN
209     return (char*)d;
210 #else
211     return (char*)(d + 1) - n;
212 #endif
213 }
214 
215 static char*
u_bottomNBytesOfDouble(double * d,int n)216 u_bottomNBytesOfDouble(double* d, int n)
217 {
218 #if U_IS_BIG_ENDIAN
219     return (char*)(d + 1) - n;
220 #else
221     return (char*)d;
222 #endif
223 }
224 #endif   /* !IEEE_754 */
225 
226 #if IEEE_754
227 static UBool
u_signBit(double d)228 u_signBit(double d) {
229     uint8_t hiByte;
230 #if U_IS_BIG_ENDIAN
231     hiByte = *(uint8_t *)&d;
232 #else
233     hiByte = *(((uint8_t *)&d) + sizeof(double) - 1);
234 #endif
235     return (hiByte & 0x80) != 0;
236 }
237 #endif
238 
239 
240 
241 #if defined (U_DEBUG_FAKETIME)
242 /* Override the clock to test things without having to move the system clock.
243  * Assumes POSIX gettimeofday() will function
244  */
245 UDate fakeClock_t0 = 0; /** Time to start the clock from **/
246 UDate fakeClock_dt = 0; /** Offset (fake time - real time) **/
247 UBool fakeClock_set = false; /** True if fake clock has spun up **/
248 
getUTCtime_real()249 static UDate getUTCtime_real() {
250     struct timeval posixTime;
251     gettimeofday(&posixTime, nullptr);
252     return (UDate)(((int64_t)posixTime.tv_sec * U_MILLIS_PER_SECOND) + (posixTime.tv_usec/1000));
253 }
254 
getUTCtime_fake()255 static UDate getUTCtime_fake() {
256     static UMutex fakeClockMutex;
257     umtx_lock(&fakeClockMutex);
258     if(!fakeClock_set) {
259         UDate real = getUTCtime_real();
260         const char *fake_start = getenv("U_FAKETIME_START");
261         if((fake_start!=nullptr) && (fake_start[0]!=0)) {
262             sscanf(fake_start,"%lf",&fakeClock_t0);
263             fakeClock_dt = fakeClock_t0 - real;
264             fprintf(stderr,"U_DEBUG_FAKETIME was set at compile time, so the ICU clock will start at a preset value\n"
265                     "env variable U_FAKETIME_START=%.0f (%s) for an offset of %.0f ms from the current time %.0f\n",
266                     fakeClock_t0, fake_start, fakeClock_dt, real);
267         } else {
268           fakeClock_dt = 0;
269             fprintf(stderr,"U_DEBUG_FAKETIME was set at compile time, but U_FAKETIME_START was not set.\n"
270                     "Set U_FAKETIME_START to the number of milliseconds since 1/1/1970 to set the ICU clock.\n");
271         }
272         fakeClock_set = true;
273     }
274     umtx_unlock(&fakeClockMutex);
275 
276     return getUTCtime_real() + fakeClock_dt;
277 }
278 #endif
279 
280 #if U_PLATFORM_USES_ONLY_WIN32_API
281 typedef union {
282     int64_t int64;
283     FILETIME fileTime;
284 } FileTimeConversion;   /* This is like a ULARGE_INTEGER */
285 
286 /* Number of 100 nanoseconds from 1/1/1601 to 1/1/1970 */
287 #define EPOCH_BIAS  INT64_C(116444736000000000)
288 #define HECTONANOSECOND_PER_MILLISECOND   10000
289 
290 #endif
291 
292 /*---------------------------------------------------------------------------
293   Universal Implementations
294   These are designed to work on all platforms.  Try these, and if they
295   don't work on your platform, then special case your platform with new
296   implementations.
297 ---------------------------------------------------------------------------*/
298 
299 U_CAPI UDate U_EXPORT2
uprv_getUTCtime()300 uprv_getUTCtime()
301 {
302 #if defined(U_DEBUG_FAKETIME)
303     return getUTCtime_fake(); /* Hook for overriding the clock */
304 #else
305     return uprv_getRawUTCtime();
306 #endif
307 }
308 
309 /* Return UTC (GMT) time measured in milliseconds since 0:00 on 1/1/70.*/
310 U_CAPI UDate U_EXPORT2
uprv_getRawUTCtime()311 uprv_getRawUTCtime()
312 {
313 #if U_PLATFORM_USES_ONLY_WIN32_API
314 
315     FileTimeConversion winTime;
316     GetSystemTimeAsFileTime(&winTime.fileTime);
317     return (UDate)((winTime.int64 - EPOCH_BIAS) / HECTONANOSECOND_PER_MILLISECOND);
318 #else
319 
320 #if HAVE_GETTIMEOFDAY
321     struct timeval posixTime;
322     gettimeofday(&posixTime, nullptr);
323     return (UDate)(((int64_t)posixTime.tv_sec * U_MILLIS_PER_SECOND) + (posixTime.tv_usec/1000));
324 #else
325     time_t epochtime;
326     time(&epochtime);
327     return (UDate)epochtime * U_MILLIS_PER_SECOND;
328 #endif
329 
330 #endif
331 }
332 
333 /*-----------------------------------------------------------------------------
334   IEEE 754
335   These methods detect and return NaN and infinity values for doubles
336   conforming to IEEE 754.  Platforms which support this standard include X86,
337   Mac 680x0, Mac PowerPC, AIX RS/6000, and most others.
338   If this doesn't work on your platform, you have non-IEEE floating-point, and
339   will need to code your own versions.  A naive implementation is to return 0.0
340   for getNaN and getInfinity, and false for isNaN and isInfinite.
341   ---------------------------------------------------------------------------*/
342 
343 U_CAPI UBool U_EXPORT2
uprv_isNaN(double number)344 uprv_isNaN(double number)
345 {
346 #if IEEE_754
347     BitPatternConversion convertedNumber;
348     convertedNumber.d64 = number;
349     /* Infinity is 0x7FF0000000000000U. Anything greater than that is a NaN */
350     return (UBool)((convertedNumber.i64 & U_INT64_MAX) > gInf.i64);
351 
352 #elif U_PLATFORM == U_PF_OS390
353     uint32_t highBits = *(uint32_t*)u_topNBytesOfDouble(&number,
354                         sizeof(uint32_t));
355     uint32_t lowBits  = *(uint32_t*)u_bottomNBytesOfDouble(&number,
356                         sizeof(uint32_t));
357 
358     return ((highBits & 0x7F080000L) == 0x7F080000L) &&
359       (lowBits == 0x00000000L);
360 
361 #else
362     /* If your platform doesn't support IEEE 754 but *does* have an NaN value,*/
363     /* you'll need to replace this default implementation with what's correct*/
364     /* for your platform.*/
365     return number != number;
366 #endif
367 }
368 
369 U_CAPI UBool U_EXPORT2
uprv_isInfinite(double number)370 uprv_isInfinite(double number)
371 {
372 #if IEEE_754
373     BitPatternConversion convertedNumber;
374     convertedNumber.d64 = number;
375     /* Infinity is exactly 0x7FF0000000000000U. */
376     return (UBool)((convertedNumber.i64 & U_INT64_MAX) == gInf.i64);
377 #elif U_PLATFORM == U_PF_OS390
378     uint32_t highBits = *(uint32_t*)u_topNBytesOfDouble(&number,
379                         sizeof(uint32_t));
380     uint32_t lowBits  = *(uint32_t*)u_bottomNBytesOfDouble(&number,
381                         sizeof(uint32_t));
382 
383     return ((highBits  & ~SIGN) == 0x70FF0000L) && (lowBits == 0x00000000L);
384 
385 #else
386     /* If your platform doesn't support IEEE 754 but *does* have an infinity*/
387     /* value, you'll need to replace this default implementation with what's*/
388     /* correct for your platform.*/
389     return number == (2.0 * number);
390 #endif
391 }
392 
393 U_CAPI UBool U_EXPORT2
uprv_isPositiveInfinity(double number)394 uprv_isPositiveInfinity(double number)
395 {
396 #if IEEE_754 || U_PLATFORM == U_PF_OS390
397     return (UBool)(number > 0 && uprv_isInfinite(number));
398 #else
399     return uprv_isInfinite(number);
400 #endif
401 }
402 
403 U_CAPI UBool U_EXPORT2
uprv_isNegativeInfinity(double number)404 uprv_isNegativeInfinity(double number)
405 {
406 #if IEEE_754 || U_PLATFORM == U_PF_OS390
407     return (UBool)(number < 0 && uprv_isInfinite(number));
408 
409 #else
410     uint32_t highBits = *(uint32_t*)u_topNBytesOfDouble(&number,
411                         sizeof(uint32_t));
412     return((highBits & SIGN) && uprv_isInfinite(number));
413 
414 #endif
415 }
416 
417 U_CAPI double U_EXPORT2
uprv_getNaN()418 uprv_getNaN()
419 {
420 #if IEEE_754 || U_PLATFORM == U_PF_OS390
421     return gNan.d64;
422 #else
423     /* If your platform doesn't support IEEE 754 but *does* have an NaN value,*/
424     /* you'll need to replace this default implementation with what's correct*/
425     /* for your platform.*/
426     return 0.0;
427 #endif
428 }
429 
430 U_CAPI double U_EXPORT2
uprv_getInfinity()431 uprv_getInfinity()
432 {
433 #if IEEE_754 || U_PLATFORM == U_PF_OS390
434     return gInf.d64;
435 #else
436     /* If your platform doesn't support IEEE 754 but *does* have an infinity*/
437     /* value, you'll need to replace this default implementation with what's*/
438     /* correct for your platform.*/
439     return 0.0;
440 #endif
441 }
442 
443 U_CAPI double U_EXPORT2
uprv_floor(double x)444 uprv_floor(double x)
445 {
446     return floor(x);
447 }
448 
449 U_CAPI double U_EXPORT2
uprv_ceil(double x)450 uprv_ceil(double x)
451 {
452     return ceil(x);
453 }
454 
455 U_CAPI double U_EXPORT2
uprv_round(double x)456 uprv_round(double x)
457 {
458     return uprv_floor(x + 0.5);
459 }
460 
461 U_CAPI double U_EXPORT2
uprv_fabs(double x)462 uprv_fabs(double x)
463 {
464     return fabs(x);
465 }
466 
467 U_CAPI double U_EXPORT2
uprv_modf(double x,double * y)468 uprv_modf(double x, double* y)
469 {
470     return modf(x, y);
471 }
472 
473 U_CAPI double U_EXPORT2
uprv_fmod(double x,double y)474 uprv_fmod(double x, double y)
475 {
476     return fmod(x, y);
477 }
478 
479 U_CAPI double U_EXPORT2
uprv_pow(double x,double y)480 uprv_pow(double x, double y)
481 {
482     /* This is declared as "double pow(double x, double y)" */
483     return pow(x, y);
484 }
485 
486 U_CAPI double U_EXPORT2
uprv_pow10(int32_t x)487 uprv_pow10(int32_t x)
488 {
489     return pow(10.0, (double)x);
490 }
491 
492 U_CAPI double U_EXPORT2
uprv_fmax(double x,double y)493 uprv_fmax(double x, double y)
494 {
495 #if IEEE_754
496     /* first handle NaN*/
497     if(uprv_isNaN(x) || uprv_isNaN(y))
498         return uprv_getNaN();
499 
500     /* check for -0 and 0*/
501     if(x == 0.0 && y == 0.0 && u_signBit(x))
502         return y;
503 
504 #endif
505 
506     /* this should work for all flt point w/o NaN and Inf special cases */
507     return (x > y ? x : y);
508 }
509 
510 U_CAPI double U_EXPORT2
uprv_fmin(double x,double y)511 uprv_fmin(double x, double y)
512 {
513 #if IEEE_754
514     /* first handle NaN*/
515     if(uprv_isNaN(x) || uprv_isNaN(y))
516         return uprv_getNaN();
517 
518     /* check for -0 and 0*/
519     if(x == 0.0 && y == 0.0 && u_signBit(y))
520         return y;
521 
522 #endif
523 
524     /* this should work for all flt point w/o NaN and Inf special cases */
525     return (x > y ? y : x);
526 }
527 
528 U_CAPI UBool U_EXPORT2
uprv_add32_overflow(int32_t a,int32_t b,int32_t * res)529 uprv_add32_overflow(int32_t a, int32_t b, int32_t* res) {
530     // NOTE: Some compilers (GCC, Clang) have primitives available, like __builtin_add_overflow.
531     // This function could be optimized by calling one of those primitives.
532     auto a64 = static_cast<int64_t>(a);
533     auto b64 = static_cast<int64_t>(b);
534     int64_t res64 = a64 + b64;
535     *res = static_cast<int32_t>(res64);
536     return res64 != *res;
537 }
538 
539 U_CAPI UBool U_EXPORT2
uprv_mul32_overflow(int32_t a,int32_t b,int32_t * res)540 uprv_mul32_overflow(int32_t a, int32_t b, int32_t* res) {
541     // NOTE: Some compilers (GCC, Clang) have primitives available, like __builtin_mul_overflow.
542     // This function could be optimized by calling one of those primitives.
543     auto a64 = static_cast<int64_t>(a);
544     auto b64 = static_cast<int64_t>(b);
545     int64_t res64 = a64 * b64;
546     *res = static_cast<int32_t>(res64);
547     return res64 != *res;
548 }
549 
550 /**
551  * Truncates the given double.
552  * trunc(3.3) = 3.0, trunc (-3.3) = -3.0
553  * This is different than calling floor() or ceil():
554  * floor(3.3) = 3, floor(-3.3) = -4
555  * ceil(3.3) = 4, ceil(-3.3) = -3
556  */
557 U_CAPI double U_EXPORT2
uprv_trunc(double d)558 uprv_trunc(double d)
559 {
560 #if IEEE_754
561     /* handle error cases*/
562     if(uprv_isNaN(d))
563         return uprv_getNaN();
564     if(uprv_isInfinite(d))
565         return uprv_getInfinity();
566 
567     if(u_signBit(d))    /* Signbit() picks up -0.0;  d<0 does not. */
568         return ceil(d);
569     else
570         return floor(d);
571 
572 #else
573     return d >= 0 ? floor(d) : ceil(d);
574 
575 #endif
576 }
577 
578 /**
579  * Return the largest positive number that can be represented by an integer
580  * type of arbitrary bit length.
581  */
582 U_CAPI double U_EXPORT2
uprv_maxMantissa()583 uprv_maxMantissa()
584 {
585     return pow(2.0, DBL_MANT_DIG + 1.0) - 1.0;
586 }
587 
588 U_CAPI double U_EXPORT2
uprv_log(double d)589 uprv_log(double d)
590 {
591     return log(d);
592 }
593 
594 U_CAPI void * U_EXPORT2
uprv_maximumPtr(void * base)595 uprv_maximumPtr(void * base)
596 {
597 #if U_PLATFORM == U_PF_OS400
598     /*
599      * With the provided function we should never be out of range of a given segment
600      * (a traditional/typical segment that is).  Our segments have 5 bytes for the
601      * id and 3 bytes for the offset.  The key is that the casting takes care of
602      * only retrieving the offset portion minus x1000.  Hence, the smallest offset
603      * seen in a program is x001000 and when casted to an int would be 0.
604      * That's why we can only add 0xffefff.  Otherwise, we would exceed the segment.
605      *
606      * Currently, 16MB is the current addressing limitation on i5/OS if the activation is
607      * non-TERASPACE.  If it is TERASPACE it is 2GB - 4k(header information).
608      * This function determines the activation based on the pointer that is passed in and
609      * calculates the appropriate maximum available size for
610      * each pointer type (TERASPACE and non-TERASPACE)
611      *
612      * Unlike other operating systems, the pointer model isn't determined at
613      * compile time on i5/OS.
614      */
615     if ((base != nullptr) && (_TESTPTR(base, _C_TERASPACE_CHECK))) {
616         /* if it is a TERASPACE pointer the max is 2GB - 4k */
617         return ((void *)(((char *)base)-((uint32_t)(base))+((uint32_t)0x7fffefff)));
618     }
619     /* otherwise 16MB since nullptr ptr is not checkable or the ptr is not TERASPACE */
620     return ((void *)(((char *)base)-((uint32_t)(base))+((uint32_t)0xffefff)));
621 
622 #else
623     return U_MAX_PTR(base);
624 #endif
625 }
626 
627 /*---------------------------------------------------------------------------
628   Platform-specific Implementations
629   Try these, and if they don't work on your platform, then special case your
630   platform with new implementations.
631   ---------------------------------------------------------------------------*/
632 
633 /* Generic time zone layer -------------------------------------------------- */
634 
635 /* Time zone utilities */
636 U_CAPI void U_EXPORT2
uprv_tzset()637 uprv_tzset()
638 {
639 #if defined(U_TZSET)
640     U_TZSET();
641 #else
642     /* no initialization*/
643 #endif
644 }
645 
646 U_CAPI int32_t U_EXPORT2
uprv_timezone()647 uprv_timezone()
648 {
649 #ifdef U_TIMEZONE
650     return U_TIMEZONE;
651 #else
652     time_t t, t1, t2;
653     struct tm tmrec;
654     int32_t tdiff = 0;
655 
656     time(&t);
657     uprv_memcpy( &tmrec, localtime(&t), sizeof(tmrec) );
658 #if U_PLATFORM != U_PF_IPHONE
659     UBool dst_checked = (tmrec.tm_isdst != 0); /* daylight savings time is checked*/
660 #endif
661     t1 = mktime(&tmrec);                 /* local time in seconds*/
662     uprv_memcpy( &tmrec, gmtime(&t), sizeof(tmrec) );
663     t2 = mktime(&tmrec);                 /* GMT (or UTC) in seconds*/
664     tdiff = t2 - t1;
665 
666 #if U_PLATFORM != U_PF_IPHONE
667     /* imitate NT behaviour, which returns same timezone offset to GMT for
668        winter and summer.
669        This does not work on all platforms. For instance, on glibc on Linux
670        and on Mac OS 10.5, tdiff calculated above remains the same
671        regardless of whether DST is in effect or not. iOS is another
672        platform where this does not work. Linux + glibc and Mac OS 10.5
673        have U_TIMEZONE defined so that this code is not reached.
674     */
675     if (dst_checked)
676         tdiff += 3600;
677 #endif
678     return tdiff;
679 #endif
680 }
681 
682 /* Note that U_TZNAME does *not* have to be tzname, but if it is,
683    some platforms need to have it declared here. */
684 
685 #if defined(U_TZNAME) && (U_PLATFORM == U_PF_IRIX || U_PLATFORM_IS_DARWIN_BASED)
686 /* RS6000 and others reject char **tzname.  */
687 extern U_IMPORT char *U_TZNAME[];
688 #endif
689 
690 #if !UCONFIG_NO_FILE_IO && ((U_PLATFORM_IS_DARWIN_BASED && (U_PLATFORM != U_PF_IPHONE || defined(U_TIMEZONE))) || U_PLATFORM_IS_LINUX_BASED || U_PLATFORM == U_PF_BSD || U_PLATFORM == U_PF_SOLARIS)
691 /* These platforms are likely to use Olson timezone IDs. */
692 /* common targets of the symbolic link at TZDEFAULT are:
693  * "/usr/share/zoneinfo/<olsonID>" default, older Linux distros, macOS to 10.12
694  * "../usr/share/zoneinfo/<olsonID>" newer Linux distros: Red Hat Enterprise Linux 7, Ubuntu 16, SuSe Linux 12
695  * "/usr/share/lib/zoneinfo/<olsonID>" Solaris
696  * "../usr/share/lib/zoneinfo/<olsonID>" Solaris
697  * "/var/db/timezone/zoneinfo/<olsonID>" macOS 10.13
698  * To avoid checking lots of paths, just check that the target path
699  * before the <olsonID> ends with "/zoneinfo/", and the <olsonID> is valid.
700  */
701 
702 #define CHECK_LOCALTIME_LINK 1
703 #if U_PLATFORM_IS_DARWIN_BASED
704 #include <tzfile.h>
705 #define TZZONEINFO      (TZDIR "/")
706 #elif U_PLATFORM == U_PF_SOLARIS
707 #define TZDEFAULT       "/etc/localtime"
708 #define TZZONEINFO      "/usr/share/lib/zoneinfo/"
709 #define TZ_ENV_CHECK    "localtime"
710 #else
711 #define TZDEFAULT       "/etc/localtime"
712 #define TZZONEINFO      "/usr/share/zoneinfo/"
713 #endif
714 #define TZZONEINFOTAIL  "/zoneinfo/"
715 #if U_HAVE_DIRENT_H
716 #define TZFILE_SKIP     "posixrules" /* tz file to skip when searching. */
717 /* Some Linux distributions have 'localtime' in /usr/share/zoneinfo
718    symlinked to /etc/localtime, which makes searchForTZFile return
719    'localtime' when it's the first match. */
720 #define TZFILE_SKIP2    "localtime"
721 #define SEARCH_TZFILE
722 #include <dirent.h>  /* Needed to search through system timezone files */
723 #endif
724 static char gTimeZoneBuffer[PATH_MAX];
725 static char *gTimeZoneBufferPtr = nullptr;
726 #endif
727 
728 #if !U_PLATFORM_USES_ONLY_WIN32_API
729 #define isNonDigit(ch) (ch < '0' || '9' < ch)
730 #define isDigit(ch) ('0' <= ch && ch <= '9')
isValidOlsonID(const char * id)731 static UBool isValidOlsonID(const char *id) {
732     int32_t idx = 0;
733     int32_t idxMax = 0;
734 
735     /* Determine if this is something like Iceland (Olson ID)
736     or AST4ADT (non-Olson ID) */
737     while (id[idx] && isNonDigit(id[idx]) && id[idx] != ',') {
738         idx++;
739     }
740 
741     /* Allow at maximum 2 numbers at the end of the id to support zone id's
742     like GMT+11. */
743     idxMax = idx + 2;
744     while (id[idx] && isDigit(id[idx]) && idx < idxMax) {
745         idx++;
746     }
747 
748     /* If we went through the whole string, then it might be okay.
749     The timezone is sometimes set to "CST-7CDT", "CST6CDT5,J129,J131/19:30",
750     "GRNLNDST3GRNLNDDT" or similar, so we cannot use it.
751     The rest of the time it could be an Olson ID. George */
752     return (UBool)(id[idx] == 0
753         || uprv_strcmp(id, "PST8PDT") == 0
754         || uprv_strcmp(id, "MST7MDT") == 0
755         || uprv_strcmp(id, "CST6CDT") == 0
756         || uprv_strcmp(id, "EST5EDT") == 0);
757 }
758 
759 /* On some Unix-like OS, 'posix' subdirectory in
760    /usr/share/zoneinfo replicates the top-level contents. 'right'
761    subdirectory has the same set of files, but individual files
762    are different from those in the top-level directory or 'posix'
763    because 'right' has files for TAI (Int'l Atomic Time) while 'posix'
764    has files for UTC.
765    When the first match for /etc/localtime is in either of them
766    (usually in posix because 'right' has different file contents),
767    or TZ environment variable points to one of them, createTimeZone
768    fails because, say, 'posix/America/New_York' is not an Olson
769    timezone id ('America/New_York' is). So, we have to skip
770    'posix/' and 'right/' at the beginning. */
skipZoneIDPrefix(const char ** id)771 static void skipZoneIDPrefix(const char** id) {
772     if (uprv_strncmp(*id, "posix/", 6) == 0
773         || uprv_strncmp(*id, "right/", 6) == 0)
774     {
775         *id += 6;
776     }
777 }
778 #endif
779 
780 #if defined(U_TZNAME) && !U_PLATFORM_USES_ONLY_WIN32_API
781 
782 #define CONVERT_HOURS_TO_SECONDS(offset) (int32_t)(offset*3600)
783 typedef struct OffsetZoneMapping {
784     int32_t offsetSeconds;
785     int32_t daylightType; /* 0=U_DAYLIGHT_NONE, 1=daylight in June-U_DAYLIGHT_JUNE, 2=daylight in December=U_DAYLIGHT_DECEMBER*/
786     const char *stdID;
787     const char *dstID;
788     const char *olsonID;
789 } OffsetZoneMapping;
790 
791 enum { U_DAYLIGHT_NONE=0,U_DAYLIGHT_JUNE=1,U_DAYLIGHT_DECEMBER=2 };
792 
793 /*
794 This list tries to disambiguate a set of abbreviated timezone IDs and offsets
795 and maps it to an Olson ID.
796 Before adding anything to this list, take a look at
797 icu/source/tools/tzcode/tz.alias
798 Sometimes no daylight savings (0) is important to define due to aliases.
799 This list can be tested with icu/source/test/compat/tzone.pl
800 More values could be added to daylightType to increase precision.
801 */
802 static const struct OffsetZoneMapping OFFSET_ZONE_MAPPINGS[] = {
803     {-45900, 2, "CHAST", "CHADT", "Pacific/Chatham"},
804     {-43200, 1, "PETT", "PETST", "Asia/Kamchatka"},
805     {-43200, 2, "NZST", "NZDT", "Pacific/Auckland"},
806     {-43200, 1, "ANAT", "ANAST", "Asia/Anadyr"},
807     {-39600, 1, "MAGT", "MAGST", "Asia/Magadan"},
808     {-37800, 2, "LHST", "LHST", "Australia/Lord_Howe"},
809     {-36000, 2, "EST", "EST", "Australia/Sydney"},
810     {-36000, 1, "SAKT", "SAKST", "Asia/Sakhalin"},
811     {-36000, 1, "VLAT", "VLAST", "Asia/Vladivostok"},
812     {-34200, 2, "CST", "CST", "Australia/South"},
813     {-32400, 1, "YAKT", "YAKST", "Asia/Yakutsk"},
814     {-32400, 1, "CHOT", "CHOST", "Asia/Choibalsan"},
815     {-31500, 2, "CWST", "CWST", "Australia/Eucla"},
816     {-28800, 1, "IRKT", "IRKST", "Asia/Irkutsk"},
817     {-28800, 1, "ULAT", "ULAST", "Asia/Ulaanbaatar"},
818     {-28800, 2, "WST", "WST", "Australia/West"},
819     {-25200, 1, "HOVT", "HOVST", "Asia/Hovd"},
820     {-25200, 1, "KRAT", "KRAST", "Asia/Krasnoyarsk"},
821     {-21600, 1, "NOVT", "NOVST", "Asia/Novosibirsk"},
822     {-21600, 1, "OMST", "OMSST", "Asia/Omsk"},
823     {-18000, 1, "YEKT", "YEKST", "Asia/Yekaterinburg"},
824     {-14400, 1, "SAMT", "SAMST", "Europe/Samara"},
825     {-14400, 1, "AMT", "AMST", "Asia/Yerevan"},
826     {-14400, 1, "AZT", "AZST", "Asia/Baku"},
827     {-10800, 1, "AST", "ADT", "Asia/Baghdad"},
828     {-10800, 1, "MSK", "MSD", "Europe/Moscow"},
829     {-10800, 1, "VOLT", "VOLST", "Europe/Volgograd"},
830     {-7200, 0, "EET", "CEST", "Africa/Tripoli"},
831     {-7200, 1, "EET", "EEST", "Europe/Athens"}, /* Conflicts with Africa/Cairo */
832     {-7200, 1, "IST", "IDT", "Asia/Jerusalem"},
833     {-3600, 0, "CET", "WEST", "Africa/Algiers"},
834     {-3600, 2, "WAT", "WAST", "Africa/Windhoek"},
835     {0, 1, "GMT", "IST", "Europe/Dublin"},
836     {0, 1, "GMT", "BST", "Europe/London"},
837     {0, 0, "WET", "WEST", "Africa/Casablanca"},
838     {0, 0, "WET", "WET", "Africa/El_Aaiun"},
839     {3600, 1, "AZOT", "AZOST", "Atlantic/Azores"},
840     {3600, 1, "EGT", "EGST", "America/Scoresbysund"},
841     {10800, 1, "PMST", "PMDT", "America/Miquelon"},
842     {10800, 2, "UYT", "UYST", "America/Montevideo"},
843     {10800, 1, "WGT", "WGST", "America/Godthab"},
844     {10800, 2, "BRT", "BRST", "Brazil/East"},
845     {12600, 1, "NST", "NDT", "America/St_Johns"},
846     {14400, 1, "AST", "ADT", "Canada/Atlantic"},
847     {14400, 2, "AMT", "AMST", "America/Cuiaba"},
848     {14400, 2, "CLT", "CLST", "Chile/Continental"},
849     {14400, 2, "FKT", "FKST", "Atlantic/Stanley"},
850     {14400, 2, "PYT", "PYST", "America/Asuncion"},
851     {18000, 1, "CST", "CDT", "America/Havana"},
852     {18000, 1, "EST", "EDT", "US/Eastern"}, /* Conflicts with America/Grand_Turk */
853     {21600, 2, "EAST", "EASST", "Chile/EasterIsland"},
854     {21600, 0, "CST", "MDT", "Canada/Saskatchewan"},
855     {21600, 0, "CST", "CDT", "America/Guatemala"},
856     {21600, 1, "CST", "CDT", "US/Central"}, /* Conflicts with Mexico/General */
857     {25200, 1, "MST", "MDT", "US/Mountain"}, /* Conflicts with Mexico/BajaSur */
858     {28800, 0, "PST", "PST", "Pacific/Pitcairn"},
859     {28800, 1, "PST", "PDT", "US/Pacific"}, /* Conflicts with Mexico/BajaNorte */
860     {32400, 1, "AKST", "AKDT", "US/Alaska"},
861     {36000, 1, "HAST", "HADT", "US/Aleutian"}
862 };
863 
864 /*#define DEBUG_TZNAME*/
865 
remapShortTimeZone(const char * stdID,const char * dstID,int32_t daylightType,int32_t offset)866 static const char* remapShortTimeZone(const char *stdID, const char *dstID, int32_t daylightType, int32_t offset)
867 {
868     int32_t idx;
869 #ifdef DEBUG_TZNAME
870     fprintf(stderr, "TZ=%s std=%s dst=%s daylight=%d offset=%d\n", getenv("TZ"), stdID, dstID, daylightType, offset);
871 #endif
872     for (idx = 0; idx < UPRV_LENGTHOF(OFFSET_ZONE_MAPPINGS); idx++)
873     {
874         if (offset == OFFSET_ZONE_MAPPINGS[idx].offsetSeconds
875             && daylightType == OFFSET_ZONE_MAPPINGS[idx].daylightType
876             && strcmp(OFFSET_ZONE_MAPPINGS[idx].stdID, stdID) == 0
877             && strcmp(OFFSET_ZONE_MAPPINGS[idx].dstID, dstID) == 0)
878         {
879             return OFFSET_ZONE_MAPPINGS[idx].olsonID;
880         }
881     }
882     return nullptr;
883 }
884 #endif
885 
886 #ifdef SEARCH_TZFILE
887 #define MAX_READ_SIZE 512
888 
889 typedef struct DefaultTZInfo {
890     char* defaultTZBuffer;
891     int64_t defaultTZFileSize;
892     FILE* defaultTZFilePtr;
893     UBool defaultTZstatus;
894     int32_t defaultTZPosition;
895 } DefaultTZInfo;
896 
897 /*
898  * This method compares the two files given to see if they are a match.
899  * It is currently use to compare two TZ files.
900  */
compareBinaryFiles(const char * defaultTZFileName,const char * TZFileName,DefaultTZInfo * tzInfo)901 static UBool compareBinaryFiles(const char* defaultTZFileName, const char* TZFileName, DefaultTZInfo* tzInfo) {
902     FILE* file;
903     int64_t sizeFile;
904     int64_t sizeFileLeft;
905     int32_t sizeFileRead;
906     int32_t sizeFileToRead;
907     char bufferFile[MAX_READ_SIZE];
908     UBool result = true;
909 
910     if (tzInfo->defaultTZFilePtr == nullptr) {
911         tzInfo->defaultTZFilePtr = fopen(defaultTZFileName, "r");
912     }
913     file = fopen(TZFileName, "r");
914 
915     tzInfo->defaultTZPosition = 0; /* reset position to begin search */
916 
917     if (file != nullptr && tzInfo->defaultTZFilePtr != nullptr) {
918         /* First check that the file size are equal. */
919         if (tzInfo->defaultTZFileSize == 0) {
920             fseek(tzInfo->defaultTZFilePtr, 0, SEEK_END);
921             tzInfo->defaultTZFileSize = ftell(tzInfo->defaultTZFilePtr);
922         }
923         fseek(file, 0, SEEK_END);
924         sizeFile = ftell(file);
925         sizeFileLeft = sizeFile;
926 
927         if (sizeFile != tzInfo->defaultTZFileSize) {
928             result = false;
929         } else {
930             /* Store the data from the files in separate buffers and
931              * compare each byte to determine equality.
932              */
933             if (tzInfo->defaultTZBuffer == nullptr) {
934                 rewind(tzInfo->defaultTZFilePtr);
935                 tzInfo->defaultTZBuffer = (char*)uprv_malloc(sizeof(char) * tzInfo->defaultTZFileSize);
936                 sizeFileRead = fread(tzInfo->defaultTZBuffer, 1, tzInfo->defaultTZFileSize, tzInfo->defaultTZFilePtr);
937             }
938             rewind(file);
939             while(sizeFileLeft > 0) {
940                 uprv_memset(bufferFile, 0, MAX_READ_SIZE);
941                 sizeFileToRead = sizeFileLeft < MAX_READ_SIZE ? sizeFileLeft : MAX_READ_SIZE;
942 
943                 sizeFileRead = fread(bufferFile, 1, sizeFileToRead, file);
944                 if (memcmp(tzInfo->defaultTZBuffer + tzInfo->defaultTZPosition, bufferFile, sizeFileRead) != 0) {
945                     result = false;
946                     break;
947                 }
948                 sizeFileLeft -= sizeFileRead;
949                 tzInfo->defaultTZPosition += sizeFileRead;
950             }
951         }
952     } else {
953         result = false;
954     }
955 
956     if (file != nullptr) {
957         fclose(file);
958     }
959 
960     return result;
961 }
962 
963 
964 /* dirent also lists two entries: "." and ".." that we can safely ignore. */
965 #define SKIP1 "."
966 #define SKIP2 ".."
967 static UBool U_CALLCONV putil_cleanup();
968 static CharString *gSearchTZFileResult = nullptr;
969 
970 /*
971  * This method recursively traverses the directory given for a matching TZ file and returns the first match.
972  * This function is not thread safe - it uses a global, gSearchTZFileResult, to hold its results.
973  */
searchForTZFile(const char * path,DefaultTZInfo * tzInfo)974 static char* searchForTZFile(const char* path, DefaultTZInfo* tzInfo) {
975     DIR* dirp = nullptr;
976     struct dirent* dirEntry = nullptr;
977     char* result = nullptr;
978     UErrorCode status = U_ZERO_ERROR;
979 
980     /* Save the current path */
981     CharString curpath(path, -1, status);
982     if (U_FAILURE(status)) {
983         goto cleanupAndReturn;
984     }
985 
986     dirp = opendir(path);
987     if (dirp == nullptr) {
988         goto cleanupAndReturn;
989     }
990 
991     if (gSearchTZFileResult == nullptr) {
992         gSearchTZFileResult = new CharString;
993         if (gSearchTZFileResult == nullptr) {
994             goto cleanupAndReturn;
995         }
996         ucln_common_registerCleanup(UCLN_COMMON_PUTIL, putil_cleanup);
997     }
998 
999     /* Check each entry in the directory. */
1000     while((dirEntry = readdir(dirp)) != nullptr) {
1001         const char* dirName = dirEntry->d_name;
1002         if (uprv_strcmp(dirName, SKIP1) != 0 && uprv_strcmp(dirName, SKIP2) != 0
1003             && uprv_strcmp(TZFILE_SKIP, dirName) != 0 && uprv_strcmp(TZFILE_SKIP2, dirName) != 0) {
1004             /* Create a newpath with the new entry to test each entry in the directory. */
1005             CharString newpath(curpath, status);
1006             newpath.append(dirName, -1, status);
1007             if (U_FAILURE(status)) {
1008                 break;
1009             }
1010 
1011             DIR* subDirp = nullptr;
1012             if ((subDirp = opendir(newpath.data())) != nullptr) {
1013                 /* If this new path is a directory, make a recursive call with the newpath. */
1014                 closedir(subDirp);
1015                 newpath.append('/', status);
1016                 if (U_FAILURE(status)) {
1017                     break;
1018                 }
1019                 result = searchForTZFile(newpath.data(), tzInfo);
1020                 /*
1021                  Have to get out here. Otherwise, we'd keep looking
1022                  and return the first match in the top-level directory
1023                  if there's a match in the top-level. If not, this function
1024                  would return nullptr and set gTimeZoneBufferPtr to nullptr in initDefault().
1025                  It worked without this in most cases because we have a fallback of calling
1026                  localtime_r to figure out the default timezone.
1027                 */
1028                 if (result != nullptr)
1029                     break;
1030             } else {
1031                 if(compareBinaryFiles(TZDEFAULT, newpath.data(), tzInfo)) {
1032                     int32_t amountToSkip = sizeof(TZZONEINFO) - 1;
1033                     if (amountToSkip > newpath.length()) {
1034                         amountToSkip = newpath.length();
1035                     }
1036                     const char* zoneid = newpath.data() + amountToSkip;
1037                     skipZoneIDPrefix(&zoneid);
1038                     gSearchTZFileResult->clear();
1039                     gSearchTZFileResult->append(zoneid, -1, status);
1040                     if (U_FAILURE(status)) {
1041                         break;
1042                     }
1043                     result = gSearchTZFileResult->data();
1044                     /* Get out after the first one found. */
1045                     break;
1046                 }
1047             }
1048         }
1049     }
1050 
1051   cleanupAndReturn:
1052     if (dirp) {
1053         closedir(dirp);
1054     }
1055     return result;
1056 }
1057 #endif
1058 
1059 #if U_PLATFORM == U_PF_ANDROID
1060 typedef int(system_property_read_callback)(const prop_info* info,
1061                                            void (*callback)(void* cookie,
1062                                                             const char* name,
1063                                                             const char* value,
1064                                                             uint32_t serial),
1065                                            void* cookie);
1066 typedef int(system_property_get)(const char*, char*);
1067 
1068 static char gAndroidTimeZone[PROP_VALUE_MAX] = { '\0' };
1069 
u_property_read(void * cookie,const char * name,const char * value,uint32_t serial)1070 static void u_property_read(void* cookie, const char* name, const char* value,
1071                             uint32_t serial) {
1072     uprv_strcpy((char* )cookie, value);
1073 }
1074 #endif
1075 
1076 U_CAPI void U_EXPORT2
uprv_tzname_clear_cache()1077 uprv_tzname_clear_cache()
1078 {
1079 #if U_PLATFORM == U_PF_ANDROID
1080     /* Android's timezone is stored in system property. */
1081     gAndroidTimeZone[0] = '\0';
1082     void* libc = dlopen("libc.so", RTLD_NOLOAD);
1083     if (libc) {
1084         /* Android API 26+ has new API to get system property and old API
1085          * (__system_property_get) is deprecated */
1086         system_property_read_callback* property_read_callback =
1087             (system_property_read_callback*)dlsym(
1088                 libc, "__system_property_read_callback");
1089         if (property_read_callback) {
1090             const prop_info* info =
1091                 __system_property_find("persist.sys.timezone");
1092             if (info) {
1093                 property_read_callback(info, &u_property_read, gAndroidTimeZone);
1094             }
1095         } else {
1096             system_property_get* property_get =
1097                 (system_property_get*)dlsym(libc, "__system_property_get");
1098             if (property_get) {
1099                 property_get("persist.sys.timezone", gAndroidTimeZone);
1100             }
1101         }
1102         dlclose(libc);
1103     }
1104 #endif
1105 
1106 #if defined(CHECK_LOCALTIME_LINK) && !defined(DEBUG_SKIP_LOCALTIME_LINK)
1107     gTimeZoneBufferPtr = nullptr;
1108 #endif
1109 }
1110 
1111 U_CAPI const char* U_EXPORT2
uprv_tzname(int n)1112 uprv_tzname(int n)
1113 {
1114     (void)n; // Avoid unreferenced parameter warning.
1115     const char *tzid = nullptr;
1116 #if U_PLATFORM_USES_ONLY_WIN32_API
1117     tzid = uprv_detectWindowsTimeZone();
1118 
1119     if (tzid != nullptr) {
1120         return tzid;
1121     }
1122 
1123 #ifndef U_TZNAME
1124     // The return value is free'd in timezone.cpp on Windows because
1125     // the other code path returns a pointer to a heap location.
1126     // If we don't have a name already, then tzname wouldn't be any
1127     // better, so just fall back.
1128     return uprv_strdup("");
1129 #endif // !U_TZNAME
1130 
1131 #else
1132 
1133 /*#if U_PLATFORM_IS_DARWIN_BASED
1134     int ret;
1135 
1136     tzid = getenv("TZFILE");
1137     if (tzid != nullptr) {
1138         return tzid;
1139     }
1140 #endif*/
1141 
1142 /* This code can be temporarily disabled to test tzname resolution later on. */
1143 #ifndef DEBUG_TZNAME
1144 #if U_PLATFORM == U_PF_ANDROID
1145     tzid = gAndroidTimeZone;
1146 #else
1147     tzid = getenv("TZ");
1148 #endif
1149     if (tzid != nullptr && isValidOlsonID(tzid)
1150 #if U_PLATFORM == U_PF_SOLARIS
1151     /* Don't misinterpret TZ "localtime" on Solaris as a time zone name. */
1152         && uprv_strcmp(tzid, TZ_ENV_CHECK) != 0
1153 #endif
1154     ) {
1155         /* The colon forces tzset() to treat the remainder as zoneinfo path */
1156         if (tzid[0] == ':') {
1157             tzid++;
1158         }
1159         /* This might be a good Olson ID. */
1160         skipZoneIDPrefix(&tzid);
1161         return tzid;
1162     }
1163     /* else U_TZNAME will give a better result. */
1164 #endif
1165 
1166 #if defined(CHECK_LOCALTIME_LINK) && !defined(DEBUG_SKIP_LOCALTIME_LINK)
1167     /* Caller must handle threading issues */
1168     if (gTimeZoneBufferPtr == nullptr) {
1169         /*
1170         This is a trick to look at the name of the link to get the Olson ID
1171         because the tzfile contents is underspecified.
1172         This isn't guaranteed to work because it may not be a symlink.
1173         */
1174         int32_t ret = (int32_t)readlink(TZDEFAULT, gTimeZoneBuffer, sizeof(gTimeZoneBuffer)-1);
1175         if (0 < ret) {
1176             int32_t tzZoneInfoTailLen = uprv_strlen(TZZONEINFOTAIL);
1177             char *  tzZoneInfoTailPtr = uprv_strstr(gTimeZoneBuffer, TZZONEINFOTAIL);
1178 
1179             if (tzZoneInfoTailPtr != nullptr
1180                 && isValidOlsonID(tzZoneInfoTailPtr + tzZoneInfoTailLen))
1181             {
1182                 return (gTimeZoneBufferPtr = tzZoneInfoTailPtr + tzZoneInfoTailLen);
1183             }
1184         } else {
1185 #if defined(SEARCH_TZFILE)
1186             DefaultTZInfo* tzInfo = (DefaultTZInfo*)uprv_malloc(sizeof(DefaultTZInfo));
1187             if (tzInfo != nullptr) {
1188                 tzInfo->defaultTZBuffer = nullptr;
1189                 tzInfo->defaultTZFileSize = 0;
1190                 tzInfo->defaultTZFilePtr = nullptr;
1191                 tzInfo->defaultTZstatus = false;
1192                 tzInfo->defaultTZPosition = 0;
1193 
1194                 gTimeZoneBufferPtr = searchForTZFile(TZZONEINFO, tzInfo);
1195 
1196                 /* Free previously allocated memory */
1197                 if (tzInfo->defaultTZBuffer != nullptr) {
1198                     uprv_free(tzInfo->defaultTZBuffer);
1199                 }
1200                 if (tzInfo->defaultTZFilePtr != nullptr) {
1201                     fclose(tzInfo->defaultTZFilePtr);
1202                 }
1203                 uprv_free(tzInfo);
1204             }
1205 
1206             if (gTimeZoneBufferPtr != nullptr && isValidOlsonID(gTimeZoneBufferPtr)) {
1207                 return gTimeZoneBufferPtr;
1208             }
1209 #endif
1210         }
1211     }
1212     else {
1213         return gTimeZoneBufferPtr;
1214     }
1215 #endif
1216 #endif
1217 
1218 #ifdef U_TZNAME
1219 #if U_PLATFORM_USES_ONLY_WIN32_API
1220     /* The return value is free'd in timezone.cpp on Windows because
1221      * the other code path returns a pointer to a heap location. */
1222     return uprv_strdup(U_TZNAME[n]);
1223 #else
1224     /*
1225     U_TZNAME is usually a non-unique abbreviation, which isn't normally usable.
1226     So we remap the abbreviation to an olson ID.
1227 
1228     Since Windows exposes a little more timezone information,
1229     we normally don't use this code on Windows because
1230     uprv_detectWindowsTimeZone should have already given the correct answer.
1231     */
1232     {
1233         struct tm juneSol, decemberSol;
1234         int daylightType;
1235         static const time_t juneSolstice=1182478260; /*2007-06-21 18:11 UT*/
1236         static const time_t decemberSolstice=1198332540; /*2007-12-22 06:09 UT*/
1237 
1238         /* This probing will tell us when daylight savings occurs.  */
1239         localtime_r(&juneSolstice, &juneSol);
1240         localtime_r(&decemberSolstice, &decemberSol);
1241         if(decemberSol.tm_isdst > 0) {
1242           daylightType = U_DAYLIGHT_DECEMBER;
1243         } else if(juneSol.tm_isdst > 0) {
1244           daylightType = U_DAYLIGHT_JUNE;
1245         } else {
1246           daylightType = U_DAYLIGHT_NONE;
1247         }
1248         tzid = remapShortTimeZone(U_TZNAME[0], U_TZNAME[1], daylightType, uprv_timezone());
1249         if (tzid != nullptr) {
1250             return tzid;
1251         }
1252     }
1253     return U_TZNAME[n];
1254 #endif
1255 #else
1256     return "";
1257 #endif
1258 }
1259 
1260 /* Get and set the ICU data directory --------------------------------------- */
1261 
1262 static icu::UInitOnce gDataDirInitOnce {};
1263 static char *gDataDirectory = nullptr;
1264 
1265 UInitOnce gTimeZoneFilesInitOnce {};
1266 static CharString *gTimeZoneFilesDirectory = nullptr;
1267 
1268 #if U_POSIX_LOCALE || U_PLATFORM_USES_ONLY_WIN32_API
1269  static const char *gCorrectedPOSIXLocale = nullptr; /* Sometimes heap allocated */
1270  static bool gCorrectedPOSIXLocaleHeapAllocated = false;
1271 #endif
1272 
putil_cleanup()1273 static UBool U_CALLCONV putil_cleanup()
1274 {
1275     if (gDataDirectory && *gDataDirectory) {
1276         uprv_free(gDataDirectory);
1277     }
1278     gDataDirectory = nullptr;
1279     gDataDirInitOnce.reset();
1280 
1281     delete gTimeZoneFilesDirectory;
1282     gTimeZoneFilesDirectory = nullptr;
1283     gTimeZoneFilesInitOnce.reset();
1284 
1285 #ifdef SEARCH_TZFILE
1286     delete gSearchTZFileResult;
1287     gSearchTZFileResult = nullptr;
1288 #endif
1289 
1290 #if U_POSIX_LOCALE || U_PLATFORM_USES_ONLY_WIN32_API
1291     if (gCorrectedPOSIXLocale && gCorrectedPOSIXLocaleHeapAllocated) {
1292         uprv_free(const_cast<char *>(gCorrectedPOSIXLocale));
1293         gCorrectedPOSIXLocale = nullptr;
1294         gCorrectedPOSIXLocaleHeapAllocated = false;
1295     }
1296 #endif
1297     return true;
1298 }
1299 
1300 /*
1301  * Set the data directory.
1302  *    Make a copy of the passed string, and set the global data dir to point to it.
1303  */
1304 U_CAPI void U_EXPORT2
u_setDataDirectory(const char * directory)1305 u_setDataDirectory(const char *directory) {
1306     char *newDataDir;
1307     int32_t length;
1308 
1309     if(directory==nullptr || *directory==0) {
1310         /* A small optimization to prevent the malloc and copy when the
1311         shared library is used, and this is a way to make sure that nullptr
1312         is never returned.
1313         */
1314         newDataDir = (char *)"";
1315     }
1316     else {
1317         length=(int32_t)uprv_strlen(directory);
1318         newDataDir = (char *)uprv_malloc(length + 2);
1319         /* Exit out if newDataDir could not be created. */
1320         if (newDataDir == nullptr) {
1321             return;
1322         }
1323         uprv_strcpy(newDataDir, directory);
1324 
1325 #if (U_FILE_SEP_CHAR != U_FILE_ALT_SEP_CHAR)
1326         {
1327             char *p;
1328             while((p = uprv_strchr(newDataDir, U_FILE_ALT_SEP_CHAR)) != nullptr) {
1329                 *p = U_FILE_SEP_CHAR;
1330             }
1331         }
1332 #endif
1333     }
1334 
1335     if (gDataDirectory && *gDataDirectory) {
1336         uprv_free(gDataDirectory);
1337     }
1338     gDataDirectory = newDataDir;
1339     ucln_common_registerCleanup(UCLN_COMMON_PUTIL, putil_cleanup);
1340 }
1341 
1342 U_CAPI UBool U_EXPORT2
uprv_pathIsAbsolute(const char * path)1343 uprv_pathIsAbsolute(const char *path)
1344 {
1345   if(!path || !*path) {
1346     return false;
1347   }
1348 
1349   if(*path == U_FILE_SEP_CHAR) {
1350     return true;
1351   }
1352 
1353 #if (U_FILE_SEP_CHAR != U_FILE_ALT_SEP_CHAR)
1354   if(*path == U_FILE_ALT_SEP_CHAR) {
1355     return true;
1356   }
1357 #endif
1358 
1359 #if U_PLATFORM_USES_ONLY_WIN32_API
1360   if( (((path[0] >= 'A') && (path[0] <= 'Z')) ||
1361        ((path[0] >= 'a') && (path[0] <= 'z'))) &&
1362       path[1] == ':' ) {
1363     return true;
1364   }
1365 #endif
1366 
1367   return false;
1368 }
1369 
1370 /* Backup setting of ICU_DATA_DIR_PREFIX_ENV_VAR
1371    (needed for some Darwin ICU build environments) */
1372 #if U_PLATFORM_IS_DARWIN_BASED && defined(TARGET_OS_SIMULATOR) && TARGET_OS_SIMULATOR
1373 # if !defined(ICU_DATA_DIR_PREFIX_ENV_VAR)
1374 #  define ICU_DATA_DIR_PREFIX_ENV_VAR "IPHONE_SIMULATOR_ROOT"
1375 # endif
1376 #endif
1377 
1378 #if defined(ICU_DATA_DIR_WINDOWS)
1379 // Helper function to get the ICU Data Directory under the Windows directory location.
getIcuDataDirectoryUnderWindowsDirectory(char * directoryBuffer,UINT bufferLength)1380 static BOOL U_CALLCONV getIcuDataDirectoryUnderWindowsDirectory(char* directoryBuffer, UINT bufferLength)
1381 {
1382     wchar_t windowsPath[MAX_PATH];
1383     char windowsPathUtf8[MAX_PATH];
1384 
1385     UINT length = GetSystemWindowsDirectoryW(windowsPath, UPRV_LENGTHOF(windowsPath));
1386     if ((length > 0) && (length < (UPRV_LENGTHOF(windowsPath) - 1))) {
1387         // Convert UTF-16 to a UTF-8 string.
1388         UErrorCode status = U_ZERO_ERROR;
1389         int32_t windowsPathUtf8Len = 0;
1390         u_strToUTF8(windowsPathUtf8, static_cast<int32_t>(UPRV_LENGTHOF(windowsPathUtf8)),
1391             &windowsPathUtf8Len, reinterpret_cast<const char16_t*>(windowsPath), -1, &status);
1392 
1393         if (U_SUCCESS(status) && (status != U_STRING_NOT_TERMINATED_WARNING) &&
1394             (windowsPathUtf8Len < (UPRV_LENGTHOF(windowsPathUtf8) - 1))) {
1395             // Ensure it always has a separator, so we can append the ICU data path.
1396             if (windowsPathUtf8[windowsPathUtf8Len - 1] != U_FILE_SEP_CHAR) {
1397                 windowsPathUtf8[windowsPathUtf8Len++] = U_FILE_SEP_CHAR;
1398                 windowsPathUtf8[windowsPathUtf8Len] = '\0';
1399             }
1400             // Check if the concatenated string will fit.
1401             if ((windowsPathUtf8Len + UPRV_LENGTHOF(ICU_DATA_DIR_WINDOWS)) < bufferLength) {
1402                 uprv_strcpy(directoryBuffer, windowsPathUtf8);
1403                 uprv_strcat(directoryBuffer, ICU_DATA_DIR_WINDOWS);
1404                 return true;
1405             }
1406         }
1407     }
1408 
1409     return false;
1410 }
1411 #endif
1412 
dataDirectoryInitFn()1413 static void U_CALLCONV dataDirectoryInitFn() {
1414     /* If we already have the directory, then return immediately. Will happen if user called
1415      * u_setDataDirectory().
1416      */
1417     if (gDataDirectory) {
1418         return;
1419     }
1420 
1421     const char *path = nullptr;
1422 #if defined(ICU_DATA_DIR_PREFIX_ENV_VAR)
1423     char datadir_path_buffer[PATH_MAX];
1424 #endif
1425 
1426     /*
1427     When ICU_NO_USER_DATA_OVERRIDE is defined, users aren't allowed to
1428     override ICU's data with the ICU_DATA environment variable. This prevents
1429     problems where multiple custom copies of ICU's specific version of data
1430     are installed on a system. Either the application must define the data
1431     directory with u_setDataDirectory, define ICU_DATA_DIR when compiling
1432     ICU, set the data with udata_setCommonData or trust that all of the
1433     required data is contained in ICU's data library that contains
1434     the entry point defined by U_ICUDATA_ENTRY_POINT.
1435 
1436     There may also be some platforms where environment variables
1437     are not allowed.
1438     */
1439 #   if !defined(ICU_NO_USER_DATA_OVERRIDE) && !UCONFIG_NO_FILE_IO
1440     /* First try to get the environment variable */
1441 #     if U_PLATFORM_HAS_WINUWP_API == 0  // Windows UWP does not support getenv
1442         path=getenv("ICU_DATA");
1443 #     endif
1444 #   endif
1445 
1446     /* ICU_DATA_DIR may be set as a compile option.
1447      * U_ICU_DATA_DEFAULT_DIR is provided and is set by ICU at compile time
1448      * and is used only when data is built in archive mode eliminating the need
1449      * for ICU_DATA_DIR to be set. U_ICU_DATA_DEFAULT_DIR is set to the installation
1450      * directory of the data dat file. Users should use ICU_DATA_DIR if they want to
1451      * set their own path.
1452      */
1453 #if defined(ICU_DATA_DIR) || defined(U_ICU_DATA_DEFAULT_DIR)
1454     if(path==nullptr || *path==0) {
1455 # if defined(ICU_DATA_DIR_PREFIX_ENV_VAR)
1456         const char *prefix = getenv(ICU_DATA_DIR_PREFIX_ENV_VAR);
1457 # endif
1458 # ifdef ICU_DATA_DIR
1459         path=ICU_DATA_DIR;
1460 # else
1461         path=U_ICU_DATA_DEFAULT_DIR;
1462 # endif
1463 # if defined(ICU_DATA_DIR_PREFIX_ENV_VAR)
1464         if (prefix != nullptr) {
1465             snprintf(datadir_path_buffer, sizeof(datadir_path_buffer), "%s%s", prefix, path);
1466             path=datadir_path_buffer;
1467         }
1468 # endif
1469     }
1470 #endif
1471 
1472 #if defined(ICU_DATA_DIR_WINDOWS)
1473     char datadir_path_buffer[MAX_PATH];
1474     if (getIcuDataDirectoryUnderWindowsDirectory(datadir_path_buffer, UPRV_LENGTHOF(datadir_path_buffer))) {
1475         path = datadir_path_buffer;
1476     }
1477 #endif
1478 
1479     if(path==nullptr) {
1480         /* It looks really bad, set it to something. */
1481         path = "";
1482     }
1483 
1484     u_setDataDirectory(path);
1485     return;
1486 }
1487 
1488 U_CAPI const char * U_EXPORT2
u_getDataDirectory()1489 u_getDataDirectory() {
1490     umtx_initOnce(gDataDirInitOnce, &dataDirectoryInitFn);
1491     return gDataDirectory;
1492 }
1493 
setTimeZoneFilesDir(const char * path,UErrorCode & status)1494 static void setTimeZoneFilesDir(const char *path, UErrorCode &status) {
1495     if (U_FAILURE(status)) {
1496         return;
1497     }
1498     gTimeZoneFilesDirectory->clear();
1499     gTimeZoneFilesDirectory->append(path, status);
1500 #if (U_FILE_SEP_CHAR != U_FILE_ALT_SEP_CHAR)
1501     char *p = gTimeZoneFilesDirectory->data();
1502     while ((p = uprv_strchr(p, U_FILE_ALT_SEP_CHAR)) != nullptr) {
1503         *p = U_FILE_SEP_CHAR;
1504     }
1505 #endif
1506 }
1507 
1508 #define TO_STRING(x) TO_STRING_2(x)
1509 #define TO_STRING_2(x) #x
1510 
TimeZoneDataDirInitFn(UErrorCode & status)1511 static void U_CALLCONV TimeZoneDataDirInitFn(UErrorCode &status) {
1512     U_ASSERT(gTimeZoneFilesDirectory == nullptr);
1513     ucln_common_registerCleanup(UCLN_COMMON_PUTIL, putil_cleanup);
1514     gTimeZoneFilesDirectory = new CharString();
1515     if (gTimeZoneFilesDirectory == nullptr) {
1516         status = U_MEMORY_ALLOCATION_ERROR;
1517         return;
1518     }
1519 
1520     const char *dir = "";
1521 
1522 #if defined(ICU_TIMEZONE_FILES_DIR_PREFIX_ENV_VAR)
1523     char timezonefilesdir_path_buffer[PATH_MAX];
1524     const char *prefix = getenv(ICU_TIMEZONE_FILES_DIR_PREFIX_ENV_VAR);
1525 #endif
1526 
1527 #if U_PLATFORM_HAS_WINUWP_API == 1
1528 // The UWP version does not support the environment variable setting.
1529 
1530 # if defined(ICU_DATA_DIR_WINDOWS)
1531     // When using the Windows system data, we can possibly pick up time zone data from the Windows directory.
1532     char datadir_path_buffer[MAX_PATH];
1533     if (getIcuDataDirectoryUnderWindowsDirectory(datadir_path_buffer, UPRV_LENGTHOF(datadir_path_buffer))) {
1534         dir = datadir_path_buffer;
1535     }
1536 # endif
1537 
1538 #else
1539     dir = getenv("ICU_TIMEZONE_FILES_DIR");
1540 #endif // U_PLATFORM_HAS_WINUWP_API
1541 
1542 #if defined(U_TIMEZONE_FILES_DIR)
1543     if (dir == nullptr) {
1544         // Build time configuration setting.
1545         dir = TO_STRING(U_TIMEZONE_FILES_DIR);
1546     }
1547 #endif
1548 
1549     if (dir == nullptr) {
1550         dir = "";
1551     }
1552 
1553 #if defined(ICU_TIMEZONE_FILES_DIR_PREFIX_ENV_VAR)
1554     if (prefix != nullptr) {
1555         snprintf(timezonefilesdir_path_buffer, sizeof(timezonefilesdir_path_buffer), "%s%s", prefix, dir);
1556         dir = timezonefilesdir_path_buffer;
1557     }
1558 #endif
1559 
1560     setTimeZoneFilesDir(dir, status);
1561 }
1562 
1563 
1564 U_CAPI const char * U_EXPORT2
u_getTimeZoneFilesDirectory(UErrorCode * status)1565 u_getTimeZoneFilesDirectory(UErrorCode *status) {
1566     umtx_initOnce(gTimeZoneFilesInitOnce, &TimeZoneDataDirInitFn, *status);
1567     return U_SUCCESS(*status) ? gTimeZoneFilesDirectory->data() : "";
1568 }
1569 
1570 U_CAPI void U_EXPORT2
u_setTimeZoneFilesDirectory(const char * path,UErrorCode * status)1571 u_setTimeZoneFilesDirectory(const char *path, UErrorCode *status) {
1572     umtx_initOnce(gTimeZoneFilesInitOnce, &TimeZoneDataDirInitFn, *status);
1573     setTimeZoneFilesDir(path, *status);
1574 
1575     // Note: this function does some extra churn, first setting based on the
1576     //       environment, then immediately replacing with the value passed in.
1577     //       The logic is simpler that way, and performance shouldn't be an issue.
1578 }
1579 
1580 
1581 #if U_POSIX_LOCALE
1582 /* A helper function used by uprv_getPOSIXIDForDefaultLocale and
1583  * uprv_getPOSIXIDForDefaultCodepage. Returns the posix locale id for
1584  * LC_CTYPE and LC_MESSAGES. It doesn't support other locale categories.
1585  */
uprv_getPOSIXIDForCategory(int category)1586 static const char *uprv_getPOSIXIDForCategory(int category)
1587 {
1588     const char* posixID = nullptr;
1589     if (category == LC_MESSAGES || category == LC_CTYPE) {
1590         /*
1591         * On Solaris two different calls to setlocale can result in
1592         * different values. Only get this value once.
1593         *
1594         * We must check this first because an application can set this.
1595         *
1596         * LC_ALL can't be used because it's platform dependent. The LANG
1597         * environment variable seems to affect LC_CTYPE variable by default.
1598         * Here is what setlocale(LC_ALL, nullptr) can return.
1599         * HPUX can return 'C C C C C C C'
1600         * Solaris can return /en_US/C/C/C/C/C on the second try.
1601         * Linux can return LC_CTYPE=C;LC_NUMERIC=C;...
1602         *
1603         * The default codepage detection also needs to use LC_CTYPE.
1604         *
1605         * Do not call setlocale(LC_*, "")! Using an empty string instead
1606         * of nullptr, will modify the libc behavior.
1607         */
1608         posixID = setlocale(category, nullptr);
1609         if ((posixID == 0)
1610             || (uprv_strcmp("C", posixID) == 0)
1611             || (uprv_strcmp("POSIX", posixID) == 0))
1612         {
1613             /* Maybe we got some garbage.  Try something more reasonable */
1614             posixID = getenv("LC_ALL");
1615             /* Solaris speaks POSIX -  See IEEE Std 1003.1-2008
1616              * This is needed to properly handle empty env. variables
1617              */
1618 #if U_PLATFORM == U_PF_SOLARIS
1619             if ((posixID == 0) || (posixID[0] == '\0')) {
1620                 posixID = getenv(category == LC_MESSAGES ? "LC_MESSAGES" : "LC_CTYPE");
1621                 if ((posixID == 0) || (posixID[0] == '\0')) {
1622 #else
1623             if (posixID == 0) {
1624                 posixID = getenv(category == LC_MESSAGES ? "LC_MESSAGES" : "LC_CTYPE");
1625                 if (posixID == 0) {
1626 #endif
1627                     posixID = getenv("LANG");
1628                 }
1629             }
1630         }
1631     }
1632     if ((posixID==0)
1633         || (uprv_strcmp("C", posixID) == 0)
1634         || (uprv_strcmp("POSIX", posixID) == 0))
1635     {
1636         /* Nothing worked.  Give it a nice POSIX default value. */
1637         posixID = "en_US_POSIX";
1638         // Note: this test will not catch 'C.UTF-8',
1639         // that will be handled in uprv_getDefaultLocaleID().
1640         // Leave this mapping here for the uprv_getPOSIXIDForDefaultCodepage()
1641         // caller which expects to see "en_US_POSIX" in many branches.
1642     }
1643     return posixID;
1644 }
1645 
1646 /* Return just the POSIX id for the default locale, whatever happens to be in
1647  * it. It gets the value from LC_MESSAGES and indirectly from LC_ALL and LANG.
1648  */
1649 static const char *uprv_getPOSIXIDForDefaultLocale()
1650 {
1651     static const char* posixID = nullptr;
1652     if (posixID == 0) {
1653         posixID = uprv_getPOSIXIDForCategory(LC_MESSAGES);
1654     }
1655     return posixID;
1656 }
1657 
1658 #if !U_CHARSET_IS_UTF8
1659 /* Return just the POSIX id for the default codepage, whatever happens to be in
1660  * it. It gets the value from LC_CTYPE and indirectly from LC_ALL and LANG.
1661  */
1662 static const char *uprv_getPOSIXIDForDefaultCodepage()
1663 {
1664     static const char* posixID = nullptr;
1665     if (posixID == 0) {
1666         posixID = uprv_getPOSIXIDForCategory(LC_CTYPE);
1667     }
1668     return posixID;
1669 }
1670 #endif
1671 #endif
1672 
1673 /* NOTE: The caller should handle thread safety */
1674 U_CAPI const char* U_EXPORT2
1675 uprv_getDefaultLocaleID()
1676 {
1677 #if U_POSIX_LOCALE
1678 /*
1679   Note that:  (a '!' means the ID is improper somehow)
1680      LC_ALL  ---->     default_loc          codepage
1681 --------------------------------------------------------
1682      ab.CD             ab                   CD
1683      ab@CD             ab__CD               -
1684      ab@CD.EF          ab__CD               EF
1685 
1686      ab_CD.EF@GH       ab_CD_GH             EF
1687 
1688 Some 'improper' ways to do the same as above:
1689   !  ab_CD@GH.EF       ab_CD_GH             EF
1690   !  ab_CD.EF@GH.IJ    ab_CD_GH             EF
1691   !  ab_CD@ZZ.EF@GH.IJ ab_CD_GH             EF
1692 
1693      _CD@GH            _CD_GH               -
1694      _CD.EF@GH         _CD_GH               EF
1695 
1696 The variant cannot have dots in it.
1697 The 'rightmost' variant (@xxx) wins.
1698 The leftmost codepage (.xxx) wins.
1699 */
1700     const char* posixID = uprv_getPOSIXIDForDefaultLocale();
1701 
1702     /* Format: (no spaces)
1703     ll [ _CC ] [ . MM ] [ @ VV]
1704 
1705       l = lang, C = ctry, M = charmap, V = variant
1706     */
1707 
1708     if (gCorrectedPOSIXLocale != nullptr) {
1709         return gCorrectedPOSIXLocale;
1710     }
1711 
1712     // Copy the ID into owned memory.
1713     // Over-allocate in case we replace "C" with "en_US_POSIX" (+10), + null termination
1714     char *correctedPOSIXLocale = static_cast<char *>(uprv_malloc(uprv_strlen(posixID) + 10 + 1));
1715     if (correctedPOSIXLocale == nullptr) {
1716         return nullptr;
1717     }
1718     uprv_strcpy(correctedPOSIXLocale, posixID);
1719 
1720     char *limit;
1721     if ((limit = uprv_strchr(correctedPOSIXLocale, '.')) != nullptr) {
1722         *limit = 0;
1723     }
1724     if ((limit = uprv_strchr(correctedPOSIXLocale, '@')) != nullptr) {
1725         *limit = 0;
1726     }
1727 
1728     if ((uprv_strcmp("C", correctedPOSIXLocale) == 0) // no @ variant
1729         || (uprv_strcmp("POSIX", correctedPOSIXLocale) == 0)) {
1730       // Raw input was C.* or POSIX.*, Give it a nice POSIX default value.
1731       // (The "C"/"POSIX" case is handled in uprv_getPOSIXIDForCategory())
1732       uprv_strcpy(correctedPOSIXLocale, "en_US_POSIX");
1733     }
1734 
1735     /* Note that we scan the *uncorrected* ID. */
1736     const char *p;
1737     if ((p = uprv_strrchr(posixID, '@')) != nullptr) {
1738         p++;
1739 
1740         /* Take care of any special cases here.. */
1741         if (!uprv_strcmp(p, "nynorsk")) {
1742             p = "NY";
1743             /* Don't worry about no__NY. In practice, it won't appear. */
1744         }
1745 
1746         if (uprv_strchr(correctedPOSIXLocale,'_') == nullptr) {
1747             uprv_strcat(correctedPOSIXLocale, "__"); /* aa@b -> aa__b (note this can make the new locale 1 char longer) */
1748         }
1749         else {
1750             uprv_strcat(correctedPOSIXLocale, "_"); /* aa_CC@b -> aa_CC_b */
1751         }
1752 
1753         const char *q;
1754         if ((q = uprv_strchr(p, '.')) != nullptr) {
1755             /* How big will the resulting string be? */
1756             int32_t len = (int32_t)(uprv_strlen(correctedPOSIXLocale) + (q-p));
1757             uprv_strncat(correctedPOSIXLocale, p, q-p); // do not include charset
1758             correctedPOSIXLocale[len] = 0;
1759         }
1760         else {
1761             /* Anything following the @ sign */
1762             uprv_strcat(correctedPOSIXLocale, p);
1763         }
1764 
1765         /* Should there be a map from 'no@nynorsk' -> no_NO_NY here?
1766          * How about 'russian' -> 'ru'?
1767          * Many of the other locales using ISO codes will be handled by the
1768          * canonicalization functions in uloc_getDefault.
1769          */
1770     }
1771 
1772     if (gCorrectedPOSIXLocale == nullptr) {
1773         gCorrectedPOSIXLocale = correctedPOSIXLocale;
1774         gCorrectedPOSIXLocaleHeapAllocated = true;
1775         ucln_common_registerCleanup(UCLN_COMMON_PUTIL, putil_cleanup);
1776         correctedPOSIXLocale = nullptr;
1777     }
1778     posixID = gCorrectedPOSIXLocale;
1779 
1780     if (correctedPOSIXLocale != nullptr) {  /* Was already set - clean up. */
1781         uprv_free(correctedPOSIXLocale);
1782     }
1783 
1784     return posixID;
1785 
1786 #elif U_PLATFORM_USES_ONLY_WIN32_API
1787 #define POSIX_LOCALE_CAPACITY 64
1788     UErrorCode status = U_ZERO_ERROR;
1789     char *correctedPOSIXLocale = nullptr;
1790 
1791     // If we have already figured this out just use the cached value
1792     if (gCorrectedPOSIXLocale != nullptr) {
1793         return gCorrectedPOSIXLocale;
1794     }
1795 
1796     // No cached value, need to determine the current value
1797     static WCHAR windowsLocale[LOCALE_NAME_MAX_LENGTH] = {};
1798     int length = GetLocaleInfoEx(LOCALE_NAME_USER_DEFAULT, LOCALE_SNAME, windowsLocale, LOCALE_NAME_MAX_LENGTH);
1799 
1800     // Now we should have a Windows locale name that needs converted to the POSIX style.
1801     if (length > 0) // If length is 0, then the GetLocaleInfoEx failed.
1802     {
1803         // First we need to go from UTF-16 to char (and also convert from _ to - while we're at it.)
1804         char modifiedWindowsLocale[LOCALE_NAME_MAX_LENGTH] = {};
1805 
1806         int32_t i;
1807         for (i = 0; i < UPRV_LENGTHOF(modifiedWindowsLocale); i++)
1808         {
1809             if (windowsLocale[i] == '_')
1810             {
1811                 modifiedWindowsLocale[i] = '-';
1812             }
1813             else
1814             {
1815                 modifiedWindowsLocale[i] = static_cast<char>(windowsLocale[i]);
1816             }
1817 
1818             if (modifiedWindowsLocale[i] == '\0')
1819             {
1820                 break;
1821             }
1822         }
1823 
1824         if (i >= UPRV_LENGTHOF(modifiedWindowsLocale))
1825         {
1826             // Ran out of room, can't really happen, maybe we'll be lucky about a matching
1827             // locale when tags are dropped
1828             modifiedWindowsLocale[UPRV_LENGTHOF(modifiedWindowsLocale) - 1] = '\0';
1829         }
1830 
1831         // Now normalize the resulting name
1832         correctedPOSIXLocale = static_cast<char *>(uprv_malloc(POSIX_LOCALE_CAPACITY + 1));
1833         /* TODO: Should we just exit on memory allocation failure? */
1834         if (correctedPOSIXLocale)
1835         {
1836             int32_t posixLen = uloc_canonicalize(modifiedWindowsLocale, correctedPOSIXLocale, POSIX_LOCALE_CAPACITY, &status);
1837             if (U_SUCCESS(status))
1838             {
1839                 *(correctedPOSIXLocale + posixLen) = 0;
1840                 gCorrectedPOSIXLocale = correctedPOSIXLocale;
1841                 gCorrectedPOSIXLocaleHeapAllocated = true;
1842                 ucln_common_registerCleanup(UCLN_COMMON_PUTIL, putil_cleanup);
1843             }
1844             else
1845             {
1846                 uprv_free(correctedPOSIXLocale);
1847             }
1848         }
1849     }
1850 
1851     // If unable to find a locale we can agree upon, use en-US by default
1852     if (gCorrectedPOSIXLocale == nullptr) {
1853         gCorrectedPOSIXLocale = "en_US";
1854     }
1855     return gCorrectedPOSIXLocale;
1856 
1857 #elif U_PLATFORM == U_PF_OS400
1858     /* locales are process scoped and are by definition thread safe */
1859     static char correctedLocale[64];
1860     const  char *localeID = getenv("LC_ALL");
1861            char *p;
1862 
1863     if (localeID == nullptr)
1864         localeID = getenv("LANG");
1865     if (localeID == nullptr)
1866         localeID = setlocale(LC_ALL, nullptr);
1867     /* Make sure we have something... */
1868     if (localeID == nullptr)
1869         return "en_US_POSIX";
1870 
1871     /* Extract the locale name from the path. */
1872     if((p = uprv_strrchr(localeID, '/')) != nullptr)
1873     {
1874         /* Increment p to start of locale name. */
1875         p++;
1876         localeID = p;
1877     }
1878 
1879     /* Copy to work location. */
1880     uprv_strcpy(correctedLocale, localeID);
1881 
1882     /* Strip off the '.locale' extension. */
1883     if((p = uprv_strchr(correctedLocale, '.')) != nullptr) {
1884         *p = 0;
1885     }
1886 
1887     /* Upper case the locale name. */
1888     T_CString_toUpperCase(correctedLocale);
1889 
1890     /* See if we are using the POSIX locale.  Any of the
1891     * following are equivalent and use the same QLGPGCMA
1892     * (POSIX) locale.
1893     * QLGPGCMA2 means UCS2
1894     * QLGPGCMA_4 means UTF-32
1895     * QLGPGCMA_8 means UTF-8
1896     */
1897     if ((uprv_strcmp("C", correctedLocale) == 0) ||
1898         (uprv_strcmp("POSIX", correctedLocale) == 0) ||
1899         (uprv_strncmp("QLGPGCMA", correctedLocale, 8) == 0))
1900     {
1901         uprv_strcpy(correctedLocale, "en_US_POSIX");
1902     }
1903     else
1904     {
1905         int16_t LocaleLen;
1906 
1907         /* Lower case the lang portion. */
1908         for(p = correctedLocale; *p != 0 && *p != '_'; p++)
1909         {
1910             *p = uprv_tolower(*p);
1911         }
1912 
1913         /* Adjust for Euro.  After '_E' add 'URO'. */
1914         LocaleLen = uprv_strlen(correctedLocale);
1915         if (correctedLocale[LocaleLen - 2] == '_' &&
1916             correctedLocale[LocaleLen - 1] == 'E')
1917         {
1918             uprv_strcat(correctedLocale, "URO");
1919         }
1920 
1921         /* If using Lotus-based locale then convert to
1922          * equivalent non Lotus.
1923          */
1924         else if (correctedLocale[LocaleLen - 2] == '_' &&
1925             correctedLocale[LocaleLen - 1] == 'L')
1926         {
1927             correctedLocale[LocaleLen - 2] = 0;
1928         }
1929 
1930         /* There are separate simplified and traditional
1931          * locales called zh_HK_S and zh_HK_T.
1932          */
1933         else if (uprv_strncmp(correctedLocale, "zh_HK", 5) == 0)
1934         {
1935             uprv_strcpy(correctedLocale, "zh_HK");
1936         }
1937 
1938         /* A special zh_CN_GBK locale...
1939         */
1940         else if (uprv_strcmp(correctedLocale, "zh_CN_GBK") == 0)
1941         {
1942             uprv_strcpy(correctedLocale, "zh_CN");
1943         }
1944 
1945     }
1946 
1947     return correctedLocale;
1948 #endif
1949 
1950 }
1951 
1952 #if !U_CHARSET_IS_UTF8
1953 #if U_POSIX_LOCALE
1954 /*
1955 Due to various platform differences, one platform may specify a charset,
1956 when they really mean a different charset. Remap the names so that they are
1957 compatible with ICU. Only conflicting/ambiguous aliases should be resolved
1958 here. Before adding anything to this function, please consider adding unique
1959 names to the ICU alias table in the data directory.
1960 */
1961 static const char*
1962 remapPlatformDependentCodepage(const char *locale, const char *name) {
1963     if (locale != nullptr && *locale == 0) {
1964         /* Make sure that an empty locale is handled the same way. */
1965         locale = nullptr;
1966     }
1967     if (name == nullptr) {
1968         return nullptr;
1969     }
1970 #if U_PLATFORM == U_PF_AIX
1971     if (uprv_strcmp(name, "IBM-943") == 0) {
1972         /* Use the ASCII compatible ibm-943 */
1973         name = "Shift-JIS";
1974     }
1975     else if (uprv_strcmp(name, "IBM-1252") == 0) {
1976         /* Use the windows-1252 that contains the Euro */
1977         name = "IBM-5348";
1978     }
1979 #elif U_PLATFORM == U_PF_SOLARIS
1980     if (locale != nullptr && uprv_strcmp(name, "EUC") == 0) {
1981         /* Solaris underspecifies the "EUC" name. */
1982         if (uprv_strcmp(locale, "zh_CN") == 0) {
1983             name = "EUC-CN";
1984         }
1985         else if (uprv_strcmp(locale, "zh_TW") == 0) {
1986             name = "EUC-TW";
1987         }
1988         else if (uprv_strcmp(locale, "ko_KR") == 0) {
1989             name = "EUC-KR";
1990         }
1991     }
1992     else if (uprv_strcmp(name, "eucJP") == 0) {
1993         /*
1994         ibm-954 is the best match.
1995         ibm-33722 is the default for eucJP (similar to Windows).
1996         */
1997         name = "eucjis";
1998     }
1999     else if (uprv_strcmp(name, "646") == 0) {
2000         /*
2001          * The default codepage given by Solaris is 646 but the C library routines treat it as if it was
2002          * ISO-8859-1 instead of US-ASCII(646).
2003          */
2004         name = "ISO-8859-1";
2005     }
2006 #elif U_PLATFORM_IS_DARWIN_BASED
2007     if (locale == nullptr && *name == 0) {
2008         /*
2009         No locale was specified, and an empty name was passed in.
2010         This usually indicates that nl_langinfo didn't return valid information.
2011         Mac OS X uses UTF-8 by default (especially the locale data and console).
2012         */
2013         name = "UTF-8";
2014     }
2015     else if (uprv_strcmp(name, "CP949") == 0) {
2016         /* Remap CP949 to a similar codepage to avoid issues with backslash and won symbol. */
2017         name = "EUC-KR";
2018     }
2019     else if (locale != nullptr && uprv_strcmp(locale, "en_US_POSIX") != 0 && uprv_strcmp(name, "US-ASCII") == 0) {
2020         /*
2021          * For non C/POSIX locale, default the code page to UTF-8 instead of US-ASCII.
2022          */
2023         name = "UTF-8";
2024     }
2025 #elif U_PLATFORM == U_PF_BSD
2026     if (uprv_strcmp(name, "CP949") == 0) {
2027         /* Remap CP949 to a similar codepage to avoid issues with backslash and won symbol. */
2028         name = "EUC-KR";
2029     }
2030 #elif U_PLATFORM == U_PF_HPUX
2031     if (locale != nullptr && uprv_strcmp(locale, "zh_HK") == 0 && uprv_strcmp(name, "big5") == 0) {
2032         /* HP decided to extend big5 as hkbig5 even though it's not compatible :-( */
2033         /* zh_TW.big5 is not the same charset as zh_HK.big5! */
2034         name = "hkbig5";
2035     }
2036     else if (uprv_strcmp(name, "eucJP") == 0) {
2037         /*
2038         ibm-1350 is the best match, but unavailable.
2039         ibm-954 is mostly a superset of ibm-1350.
2040         ibm-33722 is the default for eucJP (similar to Windows).
2041         */
2042         name = "eucjis";
2043     }
2044 #elif U_PLATFORM == U_PF_LINUX
2045     if (locale != nullptr && uprv_strcmp(name, "euc") == 0) {
2046         /* Linux underspecifies the "EUC" name. */
2047         if (uprv_strcmp(locale, "korean") == 0) {
2048             name = "EUC-KR";
2049         }
2050         else if (uprv_strcmp(locale, "japanese") == 0) {
2051             /* See comment below about eucJP */
2052             name = "eucjis";
2053         }
2054     }
2055     else if (uprv_strcmp(name, "eucjp") == 0) {
2056         /*
2057         ibm-1350 is the best match, but unavailable.
2058         ibm-954 is mostly a superset of ibm-1350.
2059         ibm-33722 is the default for eucJP (similar to Windows).
2060         */
2061         name = "eucjis";
2062     }
2063     else if (locale != nullptr && uprv_strcmp(locale, "en_US_POSIX") != 0 &&
2064             (uprv_strcmp(name, "ANSI_X3.4-1968") == 0 || uprv_strcmp(name, "US-ASCII") == 0)) {
2065         /*
2066          * For non C/POSIX locale, default the code page to UTF-8 instead of US-ASCII.
2067          */
2068         name = "UTF-8";
2069     }
2070     /*
2071      * Linux returns ANSI_X3.4-1968 for C/POSIX, but the call site takes care of
2072      * it by falling back to 'US-ASCII' when nullptr is returned from this
2073      * function. So, we don't have to worry about it here.
2074      */
2075 #endif
2076     /* return nullptr when "" is passed in */
2077     if (*name == 0) {
2078         name = nullptr;
2079     }
2080     return name;
2081 }
2082 
2083 static const char*
2084 getCodepageFromPOSIXID(const char *localeName, char * buffer, int32_t buffCapacity)
2085 {
2086     char localeBuf[100];
2087     const char *name = nullptr;
2088     char *variant = nullptr;
2089 
2090     if (localeName != nullptr && (name = (uprv_strchr(localeName, '.'))) != nullptr) {
2091         size_t localeCapacity = uprv_min(sizeof(localeBuf), (name-localeName)+1);
2092         uprv_strncpy(localeBuf, localeName, localeCapacity);
2093         localeBuf[localeCapacity-1] = 0; /* ensure NUL termination */
2094         name = uprv_strncpy(buffer, name+1, buffCapacity);
2095         buffer[buffCapacity-1] = 0; /* ensure NUL termination */
2096         if ((variant = const_cast<char *>(uprv_strchr(name, '@'))) != nullptr) {
2097             *variant = 0;
2098         }
2099         name = remapPlatformDependentCodepage(localeBuf, name);
2100     }
2101     return name;
2102 }
2103 #endif
2104 
2105 static const char*
2106 int_getDefaultCodepage()
2107 {
2108 #if U_PLATFORM == U_PF_OS400
2109     uint32_t ccsid = 37; /* Default to ibm-37 */
2110     static char codepage[64];
2111     Qwc_JOBI0400_t jobinfo;
2112     Qus_EC_t error = { sizeof(Qus_EC_t) }; /* SPI error code */
2113 
2114     EPT_CALL(QUSRJOBI)(&jobinfo, sizeof(jobinfo), "JOBI0400",
2115         "*                         ", "                ", &error);
2116 
2117     if (error.Bytes_Available == 0) {
2118         if (jobinfo.Coded_Char_Set_ID != 0xFFFF) {
2119             ccsid = (uint32_t)jobinfo.Coded_Char_Set_ID;
2120         }
2121         else if (jobinfo.Default_Coded_Char_Set_Id != 0xFFFF) {
2122             ccsid = (uint32_t)jobinfo.Default_Coded_Char_Set_Id;
2123         }
2124         /* else use the default */
2125     }
2126     snprintf(codepage, sizeof(codepage), "ibm-%d", ccsid);
2127     return codepage;
2128 
2129 #elif U_PLATFORM == U_PF_OS390
2130     static char codepage[64];
2131 
2132     strncpy(codepage, nl_langinfo(CODESET),63-strlen(UCNV_SWAP_LFNL_OPTION_STRING));
2133     strcat(codepage,UCNV_SWAP_LFNL_OPTION_STRING);
2134     codepage[63] = 0; /* NUL terminate */
2135 
2136     return codepage;
2137 
2138 #elif U_PLATFORM_USES_ONLY_WIN32_API
2139     static char codepage[64];
2140     DWORD codepageNumber = 0;
2141 
2142 #if U_PLATFORM_HAS_WINUWP_API == 1
2143     // UWP doesn't have a direct API to get the default ACP as Microsoft would rather
2144     // have folks use Unicode than a "system" code page, however this is the same
2145     // codepage as the system default locale codepage.  (FWIW, the system locale is
2146     // ONLY used for codepage, it should never be used for anything else)
2147     GetLocaleInfoEx(LOCALE_NAME_SYSTEM_DEFAULT, LOCALE_IDEFAULTANSICODEPAGE | LOCALE_RETURN_NUMBER,
2148         (LPWSTR)&codepageNumber, sizeof(codepageNumber) / sizeof(WCHAR));
2149 #else
2150     // Win32 apps can call GetACP
2151     codepageNumber = GetACP();
2152 #endif
2153     // Special case for UTF-8
2154     if (codepageNumber == 65001)
2155     {
2156         return "UTF-8";
2157     }
2158     // Windows codepages can look like windows-1252, so format the found number
2159     // the numbers are eclectic, however all valid system code pages, besides UTF-8
2160     // are between 3 and 19999
2161     if (codepageNumber > 0 && codepageNumber < 20000)
2162     {
2163         snprintf(codepage, sizeof(codepage), "windows-%ld", codepageNumber);
2164         return codepage;
2165     }
2166     // If the codepage number call failed then return UTF-8
2167     return "UTF-8";
2168 
2169 #elif U_POSIX_LOCALE
2170     static char codesetName[100];
2171     const char *localeName = nullptr;
2172     const char *name = nullptr;
2173 
2174     localeName = uprv_getPOSIXIDForDefaultCodepage();
2175     uprv_memset(codesetName, 0, sizeof(codesetName));
2176     /* On Solaris nl_langinfo returns C locale values unless setlocale
2177      * was called earlier.
2178      */
2179 #if (U_HAVE_NL_LANGINFO_CODESET && U_PLATFORM != U_PF_SOLARIS)
2180     /* When available, check nl_langinfo first because it usually gives more
2181        useful names. It depends on LC_CTYPE.
2182        nl_langinfo may use the same buffer as setlocale. */
2183     {
2184         const char *codeset = nl_langinfo(U_NL_LANGINFO_CODESET);
2185 #if U_PLATFORM_IS_DARWIN_BASED || U_PLATFORM_IS_LINUX_BASED
2186         /*
2187          * On Linux and MacOSX, ensure that default codepage for non C/POSIX locale is UTF-8
2188          * instead of ASCII.
2189          */
2190         if (uprv_strcmp(localeName, "en_US_POSIX") != 0) {
2191             codeset = remapPlatformDependentCodepage(localeName, codeset);
2192         } else
2193 #endif
2194         {
2195             codeset = remapPlatformDependentCodepage(nullptr, codeset);
2196         }
2197 
2198         if (codeset != nullptr) {
2199             uprv_strncpy(codesetName, codeset, sizeof(codesetName));
2200             codesetName[sizeof(codesetName)-1] = 0;
2201             return codesetName;
2202         }
2203     }
2204 #endif
2205 
2206     /* Use setlocale in a nice way, and then check some environment variables.
2207        Maybe the application used setlocale already.
2208     */
2209     uprv_memset(codesetName, 0, sizeof(codesetName));
2210     name = getCodepageFromPOSIXID(localeName, codesetName, sizeof(codesetName));
2211     if (name) {
2212         /* if we can find the codeset name from setlocale, return that. */
2213         return name;
2214     }
2215 
2216     if (*codesetName == 0)
2217     {
2218         /* Everything failed. Return US ASCII (ISO 646). */
2219         (void)uprv_strcpy(codesetName, "US-ASCII");
2220     }
2221     return codesetName;
2222 #else
2223     return "US-ASCII";
2224 #endif
2225 }
2226 
2227 
2228 U_CAPI const char*  U_EXPORT2
2229 uprv_getDefaultCodepage()
2230 {
2231     static char const  *name = nullptr;
2232     umtx_lock(nullptr);
2233     if (name == nullptr) {
2234         name = int_getDefaultCodepage();
2235     }
2236     umtx_unlock(nullptr);
2237     return name;
2238 }
2239 #endif  /* !U_CHARSET_IS_UTF8 */
2240 
2241 
2242 /* end of platform-specific implementation -------------- */
2243 
2244 /* version handling --------------------------------------------------------- */
2245 
2246 U_CAPI void U_EXPORT2
2247 u_versionFromString(UVersionInfo versionArray, const char *versionString) {
2248     char *end;
2249     uint16_t part=0;
2250 
2251     if(versionArray==nullptr) {
2252         return;
2253     }
2254 
2255     if(versionString!=nullptr) {
2256         for(;;) {
2257             versionArray[part]=(uint8_t)uprv_strtoul(versionString, &end, 10);
2258             if(end==versionString || ++part==U_MAX_VERSION_LENGTH || *end!=U_VERSION_DELIMITER) {
2259                 break;
2260             }
2261             versionString=end+1;
2262         }
2263     }
2264 
2265     while(part<U_MAX_VERSION_LENGTH) {
2266         versionArray[part++]=0;
2267     }
2268 }
2269 
2270 U_CAPI void U_EXPORT2
2271 u_versionFromUString(UVersionInfo versionArray, const char16_t *versionString) {
2272     if(versionArray!=nullptr && versionString!=nullptr) {
2273         char versionChars[U_MAX_VERSION_STRING_LENGTH+1];
2274         int32_t len = u_strlen(versionString);
2275         if(len>U_MAX_VERSION_STRING_LENGTH) {
2276             len = U_MAX_VERSION_STRING_LENGTH;
2277         }
2278         u_UCharsToChars(versionString, versionChars, len);
2279         versionChars[len]=0;
2280         u_versionFromString(versionArray, versionChars);
2281     }
2282 }
2283 
2284 U_CAPI void U_EXPORT2
2285 u_versionToString(const UVersionInfo versionArray, char *versionString) {
2286     uint16_t count, part;
2287     uint8_t field;
2288 
2289     if(versionString==nullptr) {
2290         return;
2291     }
2292 
2293     if(versionArray==nullptr) {
2294         versionString[0]=0;
2295         return;
2296     }
2297 
2298     /* count how many fields need to be written */
2299     for(count=4; count>0 && versionArray[count-1]==0; --count) {
2300     }
2301 
2302     if(count <= 1) {
2303         count = 2;
2304     }
2305 
2306     /* write the first part */
2307     /* write the decimal field value */
2308     field=versionArray[0];
2309     if(field>=100) {
2310         *versionString++=(char)('0'+field/100);
2311         field%=100;
2312     }
2313     if(field>=10) {
2314         *versionString++=(char)('0'+field/10);
2315         field%=10;
2316     }
2317     *versionString++=(char)('0'+field);
2318 
2319     /* write the following parts */
2320     for(part=1; part<count; ++part) {
2321         /* write a dot first */
2322         *versionString++=U_VERSION_DELIMITER;
2323 
2324         /* write the decimal field value */
2325         field=versionArray[part];
2326         if(field>=100) {
2327             *versionString++=(char)('0'+field/100);
2328             field%=100;
2329         }
2330         if(field>=10) {
2331             *versionString++=(char)('0'+field/10);
2332             field%=10;
2333         }
2334         *versionString++=(char)('0'+field);
2335     }
2336 
2337     /* NUL-terminate */
2338     *versionString=0;
2339 }
2340 
2341 U_CAPI void U_EXPORT2
2342 u_getVersion(UVersionInfo versionArray) {
2343     (void)copyright;   // Suppress unused variable warning from clang.
2344     u_versionFromString(versionArray, U_ICU_VERSION);
2345 }
2346 
2347 /**
2348  * icucfg.h dependent code
2349  */
2350 
2351 #if U_ENABLE_DYLOAD && HAVE_DLOPEN && !U_PLATFORM_USES_ONLY_WIN32_API
2352 
2353 #if HAVE_DLFCN_H
2354 #ifdef __MVS__
2355 #ifndef __SUSV3
2356 #define __SUSV3 1
2357 #endif
2358 #endif
2359 #include <dlfcn.h>
2360 #endif /* HAVE_DLFCN_H */
2361 
2362 U_CAPI void * U_EXPORT2
2363 uprv_dl_open(const char *libName, UErrorCode *status) {
2364   void *ret = nullptr;
2365   if(U_FAILURE(*status)) return ret;
2366   ret =  dlopen(libName, RTLD_NOW|RTLD_GLOBAL);
2367   if(ret==nullptr) {
2368 #ifdef U_TRACE_DYLOAD
2369     printf("dlerror on dlopen(%s): %s\n", libName, dlerror());
2370 #endif
2371     *status = U_MISSING_RESOURCE_ERROR;
2372   }
2373   return ret;
2374 }
2375 
2376 U_CAPI void U_EXPORT2
2377 uprv_dl_close(void *lib, UErrorCode *status) {
2378   if(U_FAILURE(*status)) return;
2379   dlclose(lib);
2380 }
2381 
2382 U_CAPI UVoidFunction* U_EXPORT2
2383 uprv_dlsym_func(void *lib, const char* sym, UErrorCode *status) {
2384   union {
2385       UVoidFunction *fp;
2386       void *vp;
2387   } uret;
2388   uret.fp = nullptr;
2389   if(U_FAILURE(*status)) return uret.fp;
2390   uret.vp = dlsym(lib, sym);
2391   if(uret.vp == nullptr) {
2392 #ifdef U_TRACE_DYLOAD
2393     printf("dlerror on dlsym(%p,%s): %s\n", lib,sym, dlerror());
2394 #endif
2395     *status = U_MISSING_RESOURCE_ERROR;
2396   }
2397   return uret.fp;
2398 }
2399 
2400 #elif U_ENABLE_DYLOAD && U_PLATFORM_USES_ONLY_WIN32_API && !U_PLATFORM_HAS_WINUWP_API
2401 
2402 /* Windows API implementation. */
2403 // Note: UWP does not expose/allow these APIs, so the UWP version gets the null implementation. */
2404 
2405 U_CAPI void * U_EXPORT2
2406 uprv_dl_open(const char *libName, UErrorCode *status) {
2407   HMODULE lib = nullptr;
2408 
2409   if(U_FAILURE(*status)) return nullptr;
2410 
2411   lib = LoadLibraryA(libName);
2412 
2413   if(lib==nullptr) {
2414     *status = U_MISSING_RESOURCE_ERROR;
2415   }
2416 
2417   return (void*)lib;
2418 }
2419 
2420 U_CAPI void U_EXPORT2
2421 uprv_dl_close(void *lib, UErrorCode *status) {
2422   HMODULE handle = (HMODULE)lib;
2423   if(U_FAILURE(*status)) return;
2424 
2425   FreeLibrary(handle);
2426 
2427   return;
2428 }
2429 
2430 U_CAPI UVoidFunction* U_EXPORT2
2431 uprv_dlsym_func(void *lib, const char* sym, UErrorCode *status) {
2432   HMODULE handle = (HMODULE)lib;
2433   UVoidFunction* addr = nullptr;
2434 
2435   if(U_FAILURE(*status) || lib==nullptr) return nullptr;
2436 
2437   addr = (UVoidFunction*)GetProcAddress(handle, sym);
2438 
2439   if(addr==nullptr) {
2440     DWORD lastError = GetLastError();
2441     if(lastError == ERROR_PROC_NOT_FOUND) {
2442       *status = U_MISSING_RESOURCE_ERROR;
2443     } else {
2444       *status = U_UNSUPPORTED_ERROR; /* other unknown error. */
2445     }
2446   }
2447 
2448   return addr;
2449 }
2450 
2451 #else
2452 
2453 /* No dynamic loading, null (nonexistent) implementation. */
2454 
2455 U_CAPI void * U_EXPORT2
2456 uprv_dl_open(const char *libName, UErrorCode *status) {
2457     (void)libName;
2458     if(U_FAILURE(*status)) return nullptr;
2459     *status = U_UNSUPPORTED_ERROR;
2460     return nullptr;
2461 }
2462 
2463 U_CAPI void U_EXPORT2
2464 uprv_dl_close(void *lib, UErrorCode *status) {
2465     (void)lib;
2466     if(U_FAILURE(*status)) return;
2467     *status = U_UNSUPPORTED_ERROR;
2468     return;
2469 }
2470 
2471 U_CAPI UVoidFunction* U_EXPORT2
2472 uprv_dlsym_func(void *lib, const char* sym, UErrorCode *status) {
2473   (void)lib;
2474   (void)sym;
2475   if(U_SUCCESS(*status)) {
2476     *status = U_UNSUPPORTED_ERROR;
2477   }
2478   return (UVoidFunction*)nullptr;
2479 }
2480 
2481 #endif
2482 
2483 /*
2484  * Hey, Emacs, please set the following:
2485  *
2486  * Local Variables:
2487  * indent-tabs-mode: nil
2488  * End:
2489  *
2490  */
2491