1 /* 2 ****************************************************************************** 3 * 4 * Copyright (C) 1997-2008, 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 */ 36 U_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 */ 41 U_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 */ 46 U_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 */ 51 U_INTERNAL UBool U_EXPORT2 uprv_isNegativeInfinity(double d); 52 /** 53 * Floating point utility that returns a Not a Number (NaN) value. 54 * @internal 55 */ 56 U_INTERNAL double U_EXPORT2 uprv_getNaN(void); 57 /** 58 * Floating point utility that returns an infinite value. 59 * @internal 60 */ 61 U_INTERNAL double U_EXPORT2 uprv_getInfinity(void); 62 63 /** 64 * Floating point utility to truncate a double. 65 * @internal 66 */ 67 U_INTERNAL double U_EXPORT2 uprv_trunc(double d); 68 /** 69 * Floating point utility to calculate the floor of a double. 70 * @internal 71 */ 72 U_INTERNAL double U_EXPORT2 uprv_floor(double d); 73 /** 74 * Floating point utility to calculate the ceiling of a double. 75 * @internal 76 */ 77 U_INTERNAL double U_EXPORT2 uprv_ceil(double d); 78 /** 79 * Floating point utility to calculate the absolute value of a double. 80 * @internal 81 */ 82 U_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 */ 87 U_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 */ 92 U_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 */ 97 U_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 */ 102 U_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 */ 107 U_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 */ 112 U_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 */ 117 U_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 */ 122 U_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 */ 135 U_INTERNAL double U_EXPORT2 uprv_maxMantissa(void); 136 137 /** 138 * Floating point utility to calculate the logarithm of a double. 139 * @internal 140 */ 141 U_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 */ 149 U_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 */ 194 U_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 */ 202 U_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 */ 212 U_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 */ 219 U_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 */ 227 U_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 */ 235 U_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 #endif 278