intl/icu/source/i18n/decContext.c@fc2d59ddac77
intl/icu/source/i18n/decContext.c
Wed, 31 Dec 2014 07:22:50 +0100
- author
- Michael Schloh von Bennewitz <michael@schloh.com>
- date
- Wed, 31 Dec 2014 07:22:50 +0100
- branch
- TOR_BUG_3246
- changeset 4
- fc2d59ddac77
- permissions
- -rw-r--r--
Correct previous dual key logic pending first delivery installment.
1 /* ------------------------------------------------------------------ */
2 /* Decimal Context module */
3 /* ------------------------------------------------------------------ */
4 /* Copyright (c) IBM Corporation, 2000-2012. All rights reserved. */
5 /* */
6 /* This software is made available under the terms of the */
7 /* ICU License -- ICU 1.8.1 and later. */
8 /* */
9 /* The description and User's Guide ("The decNumber C Library") for */
10 /* this software is called decNumber.pdf. This document is */
11 /* available, together with arithmetic and format specifications, */
12 /* testcases, and Web links, on the General Decimal Arithmetic page. */
13 /* */
14 /* Please send comments, suggestions, and corrections to the author: */
15 /* mfc@uk.ibm.com */
16 /* Mike Cowlishaw, IBM Fellow */
17 /* IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK */
18 /* ------------------------------------------------------------------ */
19 /* This module comprises the routines for handling arithmetic */
20 /* context structures. */
21 /* ------------------------------------------------------------------ */
23 #include <string.h> /* for strcmp */
24 #include <stdio.h> /* for printf if DECCHECK */
25 #include "decContext.h" /* context and base types */
26 #include "decNumberLocal.h" /* decNumber local types, etc. */
28 #if 0 /* ICU: No need to test endianness at runtime. */
29 /* compile-time endian tester [assumes sizeof(Int)>1] */
30 static const Int mfcone=1; /* constant 1 */
31 static const Flag *mfctop=(Flag *)&mfcone; /* -> top byte */
32 #define LITEND *mfctop /* named flag; 1=little-endian */
33 #endif
35 /* ------------------------------------------------------------------ */
36 /* decContextClearStatus -- clear bits in current status */
37 /* */
38 /* context is the context structure to be queried */
39 /* mask indicates the bits to be cleared (the status bit that */
40 /* corresponds to each 1 bit in the mask is cleared) */
41 /* returns context */
42 /* */
43 /* No error is possible. */
44 /* ------------------------------------------------------------------ */
45 U_CAPI decContext * U_EXPORT2 uprv_decContextClearStatus(decContext *context, uInt mask) {
46 context->status&=~mask;
47 return context;
48 } /* decContextClearStatus */
50 /* ------------------------------------------------------------------ */
51 /* decContextDefault -- initialize a context structure */
52 /* */
53 /* context is the structure to be initialized */
54 /* kind selects the required set of default values, one of: */
55 /* DEC_INIT_BASE -- select ANSI X3-274 defaults */
56 /* DEC_INIT_DECIMAL32 -- select IEEE 754 defaults, 32-bit */
57 /* DEC_INIT_DECIMAL64 -- select IEEE 754 defaults, 64-bit */
58 /* DEC_INIT_DECIMAL128 -- select IEEE 754 defaults, 128-bit */
59 /* For any other value a valid context is returned, but with */
60 /* Invalid_operation set in the status field. */
61 /* returns a context structure with the appropriate initial values. */
62 /* ------------------------------------------------------------------ */
63 U_CAPI decContext * U_EXPORT2 uprv_decContextDefault(decContext *context, Int kind) {
64 /* set defaults... */
65 context->digits=9; /* 9 digits */
66 context->emax=DEC_MAX_EMAX; /* 9-digit exponents */
67 context->emin=DEC_MIN_EMIN; /* .. balanced */
68 context->round=DEC_ROUND_HALF_UP; /* 0.5 rises */
69 context->traps=DEC_Errors; /* all but informational */
70 context->status=0; /* cleared */
71 context->clamp=0; /* no clamping */
72 #if DECSUBSET
73 context->extended=0; /* cleared */
74 #endif
75 switch (kind) {
76 case DEC_INIT_BASE:
77 /* [use defaults] */
78 break;
79 case DEC_INIT_DECIMAL32:
80 context->digits=7; /* digits */
81 context->emax=96; /* Emax */
82 context->emin=-95; /* Emin */
83 context->round=DEC_ROUND_HALF_EVEN; /* 0.5 to nearest even */
84 context->traps=0; /* no traps set */
85 context->clamp=1; /* clamp exponents */
86 #if DECSUBSET
87 context->extended=1; /* set */
88 #endif
89 break;
90 case DEC_INIT_DECIMAL64:
91 context->digits=16; /* digits */
92 context->emax=384; /* Emax */
93 context->emin=-383; /* Emin */
94 context->round=DEC_ROUND_HALF_EVEN; /* 0.5 to nearest even */
95 context->traps=0; /* no traps set */
96 context->clamp=1; /* clamp exponents */
97 #if DECSUBSET
98 context->extended=1; /* set */
99 #endif
100 break;
101 case DEC_INIT_DECIMAL128:
102 context->digits=34; /* digits */
103 context->emax=6144; /* Emax */
104 context->emin=-6143; /* Emin */
105 context->round=DEC_ROUND_HALF_EVEN; /* 0.5 to nearest even */
106 context->traps=0; /* no traps set */
107 context->clamp=1; /* clamp exponents */
108 #if DECSUBSET
109 context->extended=1; /* set */
110 #endif
111 break;
113 default: /* invalid Kind */
114 /* use defaults, and .. */
115 uprv_decContextSetStatus(context, DEC_Invalid_operation); /* trap */
116 }
118 return context;} /* decContextDefault */
120 /* ------------------------------------------------------------------ */
121 /* decContextGetRounding -- return current rounding mode */
122 /* */
123 /* context is the context structure to be queried */
124 /* returns the rounding mode */
125 /* */
126 /* No error is possible. */
127 /* ------------------------------------------------------------------ */
128 U_CAPI enum rounding U_EXPORT2 uprv_decContextGetRounding(decContext *context) {
129 return context->round;
130 } /* decContextGetRounding */
132 /* ------------------------------------------------------------------ */
133 /* decContextGetStatus -- return current status */
134 /* */
135 /* context is the context structure to be queried */
136 /* returns status */
137 /* */
138 /* No error is possible. */
139 /* ------------------------------------------------------------------ */
140 U_CAPI uInt U_EXPORT2 uprv_decContextGetStatus(decContext *context) {
141 return context->status;
142 } /* decContextGetStatus */
144 /* ------------------------------------------------------------------ */
145 /* decContextRestoreStatus -- restore bits in current status */
146 /* */
147 /* context is the context structure to be updated */
148 /* newstatus is the source for the bits to be restored */
149 /* mask indicates the bits to be restored (the status bit that */
150 /* corresponds to each 1 bit in the mask is set to the value of */
151 /* the correspnding bit in newstatus) */
152 /* returns context */
153 /* */
154 /* No error is possible. */
155 /* ------------------------------------------------------------------ */
156 U_CAPI decContext * U_EXPORT2 uprv_decContextRestoreStatus(decContext *context,
157 uInt newstatus, uInt mask) {
158 context->status&=~mask; /* clear the selected bits */
159 context->status|=(mask&newstatus); /* or in the new bits */
160 return context;
161 } /* decContextRestoreStatus */
163 /* ------------------------------------------------------------------ */
164 /* decContextSaveStatus -- save bits in current status */
165 /* */
166 /* context is the context structure to be queried */
167 /* mask indicates the bits to be saved (the status bits that */
168 /* correspond to each 1 bit in the mask are saved) */
169 /* returns the AND of the mask and the current status */
170 /* */
171 /* No error is possible. */
172 /* ------------------------------------------------------------------ */
173 U_CAPI uInt U_EXPORT2 uprv_decContextSaveStatus(decContext *context, uInt mask) {
174 return context->status&mask;
175 } /* decContextSaveStatus */
177 /* ------------------------------------------------------------------ */
178 /* decContextSetRounding -- set current rounding mode */
179 /* */
180 /* context is the context structure to be updated */
181 /* newround is the value which will replace the current mode */
182 /* returns context */
183 /* */
184 /* No error is possible. */
185 /* ------------------------------------------------------------------ */
186 U_CAPI decContext * U_EXPORT2 uprv_decContextSetRounding(decContext *context,
187 enum rounding newround) {
188 context->round=newround;
189 return context;
190 } /* decContextSetRounding */
192 /* ------------------------------------------------------------------ */
193 /* decContextSetStatus -- set status and raise trap if appropriate */
194 /* */
195 /* context is the context structure to be updated */
196 /* status is the DEC_ exception code */
197 /* returns the context structure */
198 /* */
199 /* Control may never return from this routine, if there is a signal */
200 /* handler and it takes a long jump. */
201 /* ------------------------------------------------------------------ */
202 U_CAPI decContext * U_EXPORT2 uprv_decContextSetStatus(decContext *context, uInt status) {
203 context->status|=status;
204 #if 0 /* ICU: Do not raise signals. */
205 if (status & context->traps) raise(SIGFPE);
206 #endif
207 return context;} /* decContextSetStatus */
209 /* ------------------------------------------------------------------ */
210 /* decContextSetStatusFromString -- set status from a string + trap */
211 /* */
212 /* context is the context structure to be updated */
213 /* string is a string exactly equal to one that might be returned */
214 /* by decContextStatusToString */
215 /* */
216 /* The status bit corresponding to the string is set, and a trap */
217 /* is raised if appropriate. */
218 /* */
219 /* returns the context structure, unless the string is equal to */
220 /* DEC_Condition_MU or is not recognized. In these cases NULL is */
221 /* returned. */
222 /* ------------------------------------------------------------------ */
223 U_CAPI decContext * U_EXPORT2 uprv_decContextSetStatusFromString(decContext *context,
224 const char *string) {
225 if (strcmp(string, DEC_Condition_CS)==0)
226 return uprv_decContextSetStatus(context, DEC_Conversion_syntax);
227 if (strcmp(string, DEC_Condition_DZ)==0)
228 return uprv_decContextSetStatus(context, DEC_Division_by_zero);
229 if (strcmp(string, DEC_Condition_DI)==0)
230 return uprv_decContextSetStatus(context, DEC_Division_impossible);
231 if (strcmp(string, DEC_Condition_DU)==0)
232 return uprv_decContextSetStatus(context, DEC_Division_undefined);
233 if (strcmp(string, DEC_Condition_IE)==0)
234 return uprv_decContextSetStatus(context, DEC_Inexact);
235 if (strcmp(string, DEC_Condition_IS)==0)
236 return uprv_decContextSetStatus(context, DEC_Insufficient_storage);
237 if (strcmp(string, DEC_Condition_IC)==0)
238 return uprv_decContextSetStatus(context, DEC_Invalid_context);
239 if (strcmp(string, DEC_Condition_IO)==0)
240 return uprv_decContextSetStatus(context, DEC_Invalid_operation);
241 #if DECSUBSET
242 if (strcmp(string, DEC_Condition_LD)==0)
243 return uprv_decContextSetStatus(context, DEC_Lost_digits);
244 #endif
245 if (strcmp(string, DEC_Condition_OV)==0)
246 return uprv_decContextSetStatus(context, DEC_Overflow);
247 if (strcmp(string, DEC_Condition_PA)==0)
248 return uprv_decContextSetStatus(context, DEC_Clamped);
249 if (strcmp(string, DEC_Condition_RO)==0)
250 return uprv_decContextSetStatus(context, DEC_Rounded);
251 if (strcmp(string, DEC_Condition_SU)==0)
252 return uprv_decContextSetStatus(context, DEC_Subnormal);
253 if (strcmp(string, DEC_Condition_UN)==0)
254 return uprv_decContextSetStatus(context, DEC_Underflow);
255 if (strcmp(string, DEC_Condition_ZE)==0)
256 return context;
257 return NULL; /* Multiple status, or unknown */
258 } /* decContextSetStatusFromString */
260 /* ------------------------------------------------------------------ */
261 /* decContextSetStatusFromStringQuiet -- set status from a string */
262 /* */
263 /* context is the context structure to be updated */
264 /* string is a string exactly equal to one that might be returned */
265 /* by decContextStatusToString */
266 /* */
267 /* The status bit corresponding to the string is set; no trap is */
268 /* raised. */
269 /* */
270 /* returns the context structure, unless the string is equal to */
271 /* DEC_Condition_MU or is not recognized. In these cases NULL is */
272 /* returned. */
273 /* ------------------------------------------------------------------ */
274 U_CAPI decContext * U_EXPORT2 uprv_decContextSetStatusFromStringQuiet(decContext *context,
275 const char *string) {
276 if (strcmp(string, DEC_Condition_CS)==0)
277 return uprv_decContextSetStatusQuiet(context, DEC_Conversion_syntax);
278 if (strcmp(string, DEC_Condition_DZ)==0)
279 return uprv_decContextSetStatusQuiet(context, DEC_Division_by_zero);
280 if (strcmp(string, DEC_Condition_DI)==0)
281 return uprv_decContextSetStatusQuiet(context, DEC_Division_impossible);
282 if (strcmp(string, DEC_Condition_DU)==0)
283 return uprv_decContextSetStatusQuiet(context, DEC_Division_undefined);
284 if (strcmp(string, DEC_Condition_IE)==0)
285 return uprv_decContextSetStatusQuiet(context, DEC_Inexact);
286 if (strcmp(string, DEC_Condition_IS)==0)
287 return uprv_decContextSetStatusQuiet(context, DEC_Insufficient_storage);
288 if (strcmp(string, DEC_Condition_IC)==0)
289 return uprv_decContextSetStatusQuiet(context, DEC_Invalid_context);
290 if (strcmp(string, DEC_Condition_IO)==0)
291 return uprv_decContextSetStatusQuiet(context, DEC_Invalid_operation);
292 #if DECSUBSET
293 if (strcmp(string, DEC_Condition_LD)==0)
294 return uprv_decContextSetStatusQuiet(context, DEC_Lost_digits);
295 #endif
296 if (strcmp(string, DEC_Condition_OV)==0)
297 return uprv_decContextSetStatusQuiet(context, DEC_Overflow);
298 if (strcmp(string, DEC_Condition_PA)==0)
299 return uprv_decContextSetStatusQuiet(context, DEC_Clamped);
300 if (strcmp(string, DEC_Condition_RO)==0)
301 return uprv_decContextSetStatusQuiet(context, DEC_Rounded);
302 if (strcmp(string, DEC_Condition_SU)==0)
303 return uprv_decContextSetStatusQuiet(context, DEC_Subnormal);
304 if (strcmp(string, DEC_Condition_UN)==0)
305 return uprv_decContextSetStatusQuiet(context, DEC_Underflow);
306 if (strcmp(string, DEC_Condition_ZE)==0)
307 return context;
308 return NULL; /* Multiple status, or unknown */
309 } /* decContextSetStatusFromStringQuiet */
311 /* ------------------------------------------------------------------ */
312 /* decContextSetStatusQuiet -- set status without trap */
313 /* */
314 /* context is the context structure to be updated */
315 /* status is the DEC_ exception code */
316 /* returns the context structure */
317 /* */
318 /* No error is possible. */
319 /* ------------------------------------------------------------------ */
320 U_CAPI decContext * U_EXPORT2 uprv_decContextSetStatusQuiet(decContext *context, uInt status) {
321 context->status|=status;
322 return context;} /* decContextSetStatusQuiet */
324 /* ------------------------------------------------------------------ */
325 /* decContextStatusToString -- convert status flags to a string */
326 /* */
327 /* context is a context with valid status field */
328 /* */
329 /* returns a constant string describing the condition. If multiple */
330 /* (or no) flags are set, a generic constant message is returned. */
331 /* ------------------------------------------------------------------ */
332 U_CAPI const char * U_EXPORT2 uprv_decContextStatusToString(const decContext *context) {
333 Int status=context->status;
335 /* test the five IEEE first, as some of the others are ambiguous when */
336 /* DECEXTFLAG=0 */
337 if (status==DEC_Invalid_operation ) return DEC_Condition_IO;
338 if (status==DEC_Division_by_zero ) return DEC_Condition_DZ;
339 if (status==DEC_Overflow ) return DEC_Condition_OV;
340 if (status==DEC_Underflow ) return DEC_Condition_UN;
341 if (status==DEC_Inexact ) return DEC_Condition_IE;
343 if (status==DEC_Division_impossible ) return DEC_Condition_DI;
344 if (status==DEC_Division_undefined ) return DEC_Condition_DU;
345 if (status==DEC_Rounded ) return DEC_Condition_RO;
346 if (status==DEC_Clamped ) return DEC_Condition_PA;
347 if (status==DEC_Subnormal ) return DEC_Condition_SU;
348 if (status==DEC_Conversion_syntax ) return DEC_Condition_CS;
349 if (status==DEC_Insufficient_storage ) return DEC_Condition_IS;
350 if (status==DEC_Invalid_context ) return DEC_Condition_IC;
351 #if DECSUBSET
352 if (status==DEC_Lost_digits ) return DEC_Condition_LD;
353 #endif
354 if (status==0 ) return DEC_Condition_ZE;
355 return DEC_Condition_MU; /* Multiple errors */
356 } /* decContextStatusToString */
358 /* ------------------------------------------------------------------ */
359 /* decContextTestEndian -- test whether DECLITEND is set correctly */
360 /* */
361 /* quiet is 1 to suppress message; 0 otherwise */
362 /* returns 0 if DECLITEND is correct */
363 /* 1 if DECLITEND is incorrect and should be 1 */
364 /* -1 if DECLITEND is incorrect and should be 0 */
365 /* */
366 /* A message is displayed if the return value is not 0 and quiet==0. */
367 /* */
368 /* No error is possible. */
369 /* ------------------------------------------------------------------ */
370 #if 0 /* ICU: Unused function. Anyway, do not call printf(). */
371 U_CAPI Int U_EXPORT2 uprv_decContextTestEndian(Flag quiet) {
372 Int res=0; /* optimist */
373 uInt dle=(uInt)DECLITEND; /* unsign */
374 if (dle>1) dle=1; /* ensure 0 or 1 */
376 if (LITEND!=DECLITEND) {
377 const char *adj;
378 if (!quiet) {
379 if (LITEND) adj="little";
380 else adj="big";
381 printf("Warning: DECLITEND is set to %d, but this computer appears to be %s-endian\n",
382 DECLITEND, adj);
383 }
384 res=(Int)LITEND-dle;
385 }
386 return res;
387 } /* decContextTestEndian */
388 #endif
390 /* ------------------------------------------------------------------ */
391 /* decContextTestSavedStatus -- test bits in saved status */
392 /* */
393 /* oldstatus is the status word to be tested */
394 /* mask indicates the bits to be tested (the oldstatus bits that */
395 /* correspond to each 1 bit in the mask are tested) */
396 /* returns 1 if any of the tested bits are 1, or 0 otherwise */
397 /* */
398 /* No error is possible. */
399 /* ------------------------------------------------------------------ */
400 U_CAPI uInt U_EXPORT2 uprv_decContextTestSavedStatus(uInt oldstatus, uInt mask) {
401 return (oldstatus&mask)!=0;
402 } /* decContextTestSavedStatus */
404 /* ------------------------------------------------------------------ */
405 /* decContextTestStatus -- test bits in current status */
406 /* */
407 /* context is the context structure to be updated */
408 /* mask indicates the bits to be tested (the status bits that */
409 /* correspond to each 1 bit in the mask are tested) */
410 /* returns 1 if any of the tested bits are 1, or 0 otherwise */
411 /* */
412 /* No error is possible. */
413 /* ------------------------------------------------------------------ */
414 U_CAPI uInt U_EXPORT2 uprv_decContextTestStatus(decContext *context, uInt mask) {
415 return (context->status&mask)!=0;
416 } /* decContextTestStatus */
418 /* ------------------------------------------------------------------ */
419 /* decContextZeroStatus -- clear all status bits */
420 /* */
421 /* context is the context structure to be updated */
422 /* returns context */
423 /* */
424 /* No error is possible. */
425 /* ------------------------------------------------------------------ */
426 U_CAPI decContext * U_EXPORT2 uprv_decContextZeroStatus(decContext *context) {
427 context->status=0;
428 return context;
429 } /* decContextZeroStatus */
