putilimp.h revision 50294ead5e5d23f5bbfed76e00e6b510bd41eee1
1/* 2****************************************************************************** 3* 4* Copyright (C) 1997-2010, International Business Machines 5* Corporation and others. All Rights Reserved. 6* 7****************************************************************************** 8* 9* FILE NAME : putilimp.h 10* 11* Date Name Description 12* 10/17/04 grhoten Move internal functions from putil.h to this file. 13****************************************************************************** 14*/ 15 16#ifndef PUTILIMP_H 17#define PUTILIMP_H 18 19#include "unicode/utypes.h" 20#include "unicode/putil.h" 21 22/*==========================================================================*/ 23/* Platform utilities */ 24/*==========================================================================*/ 25 26/** 27 * Platform utilities isolates the platform dependencies of the 28 * libarary. For each platform which this code is ported to, these 29 * functions may have to be re-implemented. 30 */ 31 32/** 33 * Floating point utility to determine if a double is Not a Number (NaN). 34 * @internal 35 */ 36U_INTERNAL UBool U_EXPORT2 uprv_isNaN(double d); 37/** 38 * Floating point utility to determine if a double has an infinite value. 39 * @internal 40 */ 41U_INTERNAL UBool U_EXPORT2 uprv_isInfinite(double d); 42/** 43 * Floating point utility to determine if a double has a positive infinite value. 44 * @internal 45 */ 46U_INTERNAL UBool U_EXPORT2 uprv_isPositiveInfinity(double d); 47/** 48 * Floating point utility to determine if a double has a negative infinite value. 49 * @internal 50 */ 51U_INTERNAL UBool U_EXPORT2 uprv_isNegativeInfinity(double d); 52/** 53 * Floating point utility that returns a Not a Number (NaN) value. 54 * @internal 55 */ 56U_INTERNAL double U_EXPORT2 uprv_getNaN(void); 57/** 58 * Floating point utility that returns an infinite value. 59 * @internal 60 */ 61U_INTERNAL double U_EXPORT2 uprv_getInfinity(void); 62 63/** 64 * Floating point utility to truncate a double. 65 * @internal 66 */ 67U_INTERNAL double U_EXPORT2 uprv_trunc(double d); 68/** 69 * Floating point utility to calculate the floor of a double. 70 * @internal 71 */ 72U_INTERNAL double U_EXPORT2 uprv_floor(double d); 73/** 74 * Floating point utility to calculate the ceiling of a double. 75 * @internal 76 */ 77U_INTERNAL double U_EXPORT2 uprv_ceil(double d); 78/** 79 * Floating point utility to calculate the absolute value of a double. 80 * @internal 81 */ 82U_INTERNAL double U_EXPORT2 uprv_fabs(double d); 83/** 84 * Floating point utility to calculate the fractional and integer parts of a double. 85 * @internal 86 */ 87U_INTERNAL double U_EXPORT2 uprv_modf(double d, double* pinteger); 88/** 89 * Floating point utility to calculate the remainder of a double divided by another double. 90 * @internal 91 */ 92U_INTERNAL double U_EXPORT2 uprv_fmod(double d, double y); 93/** 94 * Floating point utility to calculate d to the power of exponent (d^exponent). 95 * @internal 96 */ 97U_INTERNAL double U_EXPORT2 uprv_pow(double d, double exponent); 98/** 99 * Floating point utility to calculate 10 to the power of exponent (10^exponent). 100 * @internal 101 */ 102U_INTERNAL double U_EXPORT2 uprv_pow10(int32_t exponent); 103/** 104 * Floating point utility to calculate the maximum value of two doubles. 105 * @internal 106 */ 107U_INTERNAL double U_EXPORT2 uprv_fmax(double d, double y); 108/** 109 * Floating point utility to calculate the minimum value of two doubles. 110 * @internal 111 */ 112U_INTERNAL double U_EXPORT2 uprv_fmin(double d, double y); 113/** 114 * Private utility to calculate the maximum value of two integers. 115 * @internal 116 */ 117U_INTERNAL int32_t U_EXPORT2 uprv_max(int32_t d, int32_t y); 118/** 119 * Private utility to calculate the minimum value of two integers. 120 * @internal 121 */ 122U_INTERNAL int32_t U_EXPORT2 uprv_min(int32_t d, int32_t y); 123 124#if U_IS_BIG_ENDIAN 125# define uprv_isNegative(number) (*((signed char *)&(number))<0) 126#else 127# define uprv_isNegative(number) (*((signed char *)&(number)+sizeof(number)-1)<0) 128#endif 129 130/** 131 * Return the largest positive number that can be represented by an integer 132 * type of arbitrary bit length. 133 * @internal 134 */ 135U_INTERNAL double U_EXPORT2 uprv_maxMantissa(void); 136 137/** 138 * Floating point utility to calculate the logarithm of a double. 139 * @internal 140 */ 141U_INTERNAL double U_EXPORT2 uprv_log(double d); 142 143/** 144 * Does common notion of rounding e.g. uprv_floor(x + 0.5); 145 * @param x the double number 146 * @return the rounded double 147 * @internal 148 */ 149U_INTERNAL double U_EXPORT2 uprv_round(double x); 150 151#if 0 152/** 153 * Returns the number of digits after the decimal point in a double number x. 154 * 155 * @param x the double number 156 * @return the number of digits after the decimal point in a double number x. 157 * @internal 158 */ 159/*U_INTERNAL int32_t U_EXPORT2 uprv_digitsAfterDecimal(double x);*/ 160#endif 161 162/** 163 * Time zone utilities 164 * 165 * Wrappers for C runtime library functions relating to timezones. 166 * The t_tzset() function (similar to tzset) uses the current setting 167 * of the environment variable TZ to assign values to three global 168 * variables: daylight, timezone, and tzname. These variables have the 169 * following meanings, and are declared in <time.h>. 170 * 171 * daylight Nonzero if daylight-saving-time zone (DST) is specified 172 * in TZ; otherwise, 0. Default value is 1. 173 * timezone Difference in seconds between coordinated universal 174 * time and local time. E.g., -28,800 for PST (GMT-8hrs) 175 * tzname(0) Three-letter time-zone name derived from TZ environment 176 * variable. E.g., "PST". 177 * tzname(1) Three-letter DST zone name derived from TZ environment 178 * variable. E.g., "PDT". If DST zone is omitted from TZ, 179 * tzname(1) is an empty string. 180 * 181 * Notes: For example, to set the TZ environment variable to correspond 182 * to the current time zone in Germany, you can use one of the 183 * following statements: 184 * 185 * set TZ=GST1GDT 186 * set TZ=GST+1GDT 187 * 188 * If the TZ value is not set, t_tzset() attempts to use the time zone 189 * information specified by the operating system. Under Windows NT 190 * and Windows 95, this information is specified in the Control Panel's 191 * Date/Time application. 192 * @internal 193 */ 194U_INTERNAL void U_EXPORT2 uprv_tzset(void); 195 196/** 197 * Difference in seconds between coordinated universal 198 * time and local time. E.g., -28,800 for PST (GMT-8hrs) 199 * @return the difference in seconds between coordinated universal time and local time. 200 * @internal 201 */ 202U_INTERNAL int32_t U_EXPORT2 uprv_timezone(void); 203 204/** 205 * tzname(0) Three-letter time-zone name derived from TZ environment 206 * variable. E.g., "PST". 207 * tzname(1) Three-letter DST zone name derived from TZ environment 208 * variable. E.g., "PDT". If DST zone is omitted from TZ, 209 * tzname(1) is an empty string. 210 * @internal 211 */ 212U_INTERNAL const char* U_EXPORT2 uprv_tzname(int n); 213 214/** 215 * Get UTC (GMT) time measured in milliseconds since 0:00 on 1/1/1970. 216 * @return the UTC time measured in milliseconds 217 * @internal 218 */ 219U_INTERNAL UDate U_EXPORT2 uprv_getUTCtime(void); 220 221/** 222 * Determine whether a pathname is absolute or not, as defined by the platform. 223 * @param path Pathname to test 224 * @return TRUE if the path is absolute 225 * @internal (ICU 3.0) 226 */ 227U_INTERNAL UBool U_EXPORT2 uprv_pathIsAbsolute(const char *path); 228 229/** 230 * Use U_MAX_PTR instead of this function. 231 * @param void pointer to test 232 * @return the largest possible pointer greater than the base 233 * @internal (ICU 3.8) 234 */ 235U_INTERNAL void * U_EXPORT2 uprv_maximumPtr(void *base); 236 237/** 238 * Maximum value of a (void*) - use to indicate the limit of an 'infinite' buffer. 239 * In fact, buffer sizes must not exceed 2GB so that the difference between 240 * the buffer limit and the buffer start can be expressed in an int32_t. 241 * 242 * The definition of U_MAX_PTR must fulfill the following conditions: 243 * - return the largest possible pointer greater than base 244 * - return a valid pointer according to the machine architecture (AS/400, 64-bit, etc.) 245 * - avoid wrapping around at high addresses 246 * - make sure that the returned pointer is not farther from base than 0x7fffffff 247 * 248 * @param base The beginning of a buffer to find the maximum offset from 249 * @internal 250 */ 251#ifndef U_MAX_PTR 252# if defined(OS390) && !defined(_LP64) 253 /* We have 31-bit pointers. */ 254# define U_MAX_PTR(base) ((void *)0x7fffffff) 255# elif defined(OS400) 256# define U_MAX_PTR(base) uprv_maximumPtr((void *)base) 257# elif defined(__GNUC__) && __GNUC__ >= 4 258/* 259 * Due to a compiler optimization bug, gcc 4 causes test failures when doing 260 * this math arithmetic on pointers on some platforms. It seems like the 261 * pointers are considered signed instead of unsigned. The uintptr_t type 262 * isn't available on all platforms (i.e MSVC 6) and pointers aren't always 263 * a scalar value (i.e. i5/OS see uprv_maximumPtr function). 264 */ 265# define U_MAX_PTR(base) \ 266 ((void *)(((uintptr_t)(base)+0x7fffffffu) > (uintptr_t)(base) \ 267 ? ((uintptr_t)(base)+0x7fffffffu) \ 268 : (uintptr_t)-1)) 269# else 270# define U_MAX_PTR(base) \ 271 ((char *)(((char *)(base)+0x7fffffffu) > (char *)(base) \ 272 ? ((char *)(base)+0x7fffffffu) \ 273 : (char *)-1)) 274# endif 275#endif 276 277#if U_ENABLE_DYLOAD 278/* Dynamic Library Functions */ 279 280/** 281 * Load a library 282 * @internal (ICU 4.4) 283 */ 284U_INTERNAL void * U_EXPORT2 uprv_dl_open(const char *libName, UErrorCode *status); 285 286/** 287 * Close a library 288 * @internal (ICU 4.4) 289 */ 290U_INTERNAL void U_EXPORT2 uprv_dl_close( void *lib, UErrorCode *status); 291 292/** 293 * Extract a symbol from a library 294 * @internal (ICU 4.4) 295 */ 296U_INTERNAL void * U_EXPORT2 uprv_dl_sym( void *lib, const char *symbolName, UErrorCode *status); 297 298#endif 299 300#endif 301