skia / external / github.com / unicode-org / icu / refs/tags/icu-release-3-2-1 / . / source / common / putilimp.h

/* | |

****************************************************************************** | |

* | |

* Copyright (C) 1997-2004, International Business Machines | |

* Corporation and others. All Rights Reserved. | |

* | |

****************************************************************************** | |

* | |

* FILE NAME : putilimp.h | |

* | |

* Date Name Description | |

* 10/17/04 grhoten Move internal functions from putil.h to this file. | |

****************************************************************************** | |

*/ | |

#ifndef PUTILIMP_H | |

#define PUTILIMP_H | |

#include "unicode/utypes.h" | |

#include "unicode/putil.h" | |

/*==========================================================================*/ | |

/* Platform utilities */ | |

/*==========================================================================*/ | |

/** | |

* Platform utilities isolates the platform dependencies of the | |

* libarary. For each platform which this code is ported to, these | |

* functions may have to be re-implemented. | |

*/ | |

/** | |

* Floating point utility to determine if a double is Not a Number (NaN). | |

* @internal | |

*/ | |

U_INTERNAL UBool U_EXPORT2 uprv_isNaN(double d); | |

/** | |

* Floating point utility to determine if a double has an infinite value. | |

* @internal | |

*/ | |

U_INTERNAL UBool U_EXPORT2 uprv_isInfinite(double d); | |

/** | |

* Floating point utility to determine if a double has a positive infinite value. | |

* @internal | |

*/ | |

U_INTERNAL UBool U_EXPORT2 uprv_isPositiveInfinity(double d); | |

/** | |

* Floating point utility to determine if a double has a negative infinite value. | |

* @internal | |

*/ | |

U_INTERNAL UBool U_EXPORT2 uprv_isNegativeInfinity(double d); | |

/** | |

* Floating point utility that returns a Not a Number (NaN) value. | |

* @internal | |

*/ | |

U_INTERNAL double U_EXPORT2 uprv_getNaN(void); | |

/** | |

* Floating point utility that returns an infinite value. | |

* @internal | |

*/ | |

U_INTERNAL double U_EXPORT2 uprv_getInfinity(void); | |

/** | |

* Floating point utility to truncate a double. | |

* @internal | |

*/ | |

U_INTERNAL double U_EXPORT2 uprv_trunc(double d); | |

/** | |

* Floating point utility to calculate the floor of a double. | |

* @internal | |

*/ | |

U_INTERNAL double U_EXPORT2 uprv_floor(double d); | |

/** | |

* Floating point utility to calculate the ceiling of a double. | |

* @internal | |

*/ | |

U_INTERNAL double U_EXPORT2 uprv_ceil(double d); | |

/** | |

* Floating point utility to calculate the absolute value of a double. | |

* @internal | |

*/ | |

U_INTERNAL double U_EXPORT2 uprv_fabs(double d); | |

/** | |

* Floating point utility to calculate the fractional and integer parts of a double. | |

* @internal | |

*/ | |

U_INTERNAL double U_EXPORT2 uprv_modf(double d, double* pinteger); | |

/** | |

* Floating point utility to calculate the remainder of a double divided by another double. | |

* @internal | |

*/ | |

U_INTERNAL double U_EXPORT2 uprv_fmod(double d, double y); | |

/** | |

* Floating point utility to calculate d to the power of exponent (d^exponent). | |

* @internal | |

*/ | |

U_INTERNAL double U_EXPORT2 uprv_pow(double d, double exponent); | |

/** | |

* Floating point utility to calculate 10 to the power of exponent (10^exponent). | |

* @internal | |

*/ | |

U_INTERNAL double U_EXPORT2 uprv_pow10(int32_t exponent); | |

/** | |

* Floating point utility to calculate the maximum value of two doubles. | |

* @internal | |

*/ | |

U_INTERNAL double U_EXPORT2 uprv_fmax(double d, double y); | |

/** | |

* Floating point utility to calculate the minimum value of two doubles. | |

* @internal | |

*/ | |

U_INTERNAL double U_EXPORT2 uprv_fmin(double d, double y); | |

/** | |

* Private utility to calculate the maximum value of two integers. | |

* @internal | |

*/ | |

U_INTERNAL int32_t U_EXPORT2 uprv_max(int32_t d, int32_t y); | |

/** | |

* Private utility to calculate the minimum value of two integers. | |

* @internal | |

*/ | |

U_INTERNAL int32_t U_EXPORT2 uprv_min(int32_t d, int32_t y); | |

#if U_IS_BIG_ENDIAN | |

# define uprv_isNegative(number) (*((signed char *)&(number))<0) | |

#else | |

# define uprv_isNegative(number) (*((signed char *)&(number)+sizeof(number)-1)<0) | |

#endif | |

/** | |

* Return the largest positive number that can be represented by an integer | |

* type of arbitrary bit length. | |

* @internal | |

*/ | |

U_INTERNAL double U_EXPORT2 uprv_maxMantissa(void); | |

/** | |

* Return the floor of the log base 10 of a given double. | |

* This method compensates for inaccuracies which arise naturally when | |

* computing logs, and always gives the correct value. The parameter | |

* must be positive and finite. | |

* (Thanks to Alan Liu for supplying this function.) | |

* | |

* @param d the double value to apply the common log function for. | |

* @return the log of value d. | |

* @internal | |

*/ | |

U_INTERNAL int16_t U_EXPORT2 uprv_log10(double d); | |

/** | |

* Floating point utility to calculate the logarithm of a double. | |

* @internal | |

*/ | |

U_INTERNAL double U_EXPORT2 uprv_log(double d); | |

/** | |

* Does common notion of rounding e.g. uprv_floor(x + 0.5); | |

* @param x the double number | |

* @return the rounded double | |

* @internal | |

*/ | |

U_INTERNAL double U_EXPORT2 uprv_round(double x); | |

#if 0 | |

/** | |

* Returns the number of digits after the decimal point in a double number x. | |

* | |

* @param x the double number | |

* @return the number of digits after the decimal point in a double number x. | |

* @internal | |

*/ | |

/*U_INTERNAL int32_t U_EXPORT2 uprv_digitsAfterDecimal(double x);*/ | |

#endif | |

/** | |

* Time zone utilities | |

* | |

* Wrappers for C runtime library functions relating to timezones. | |

* The t_tzset() function (similar to tzset) uses the current setting | |

* of the environment variable TZ to assign values to three global | |

* variables: daylight, timezone, and tzname. These variables have the | |

* following meanings, and are declared in <time.h>. | |

* | |

* daylight Nonzero if daylight-saving-time zone (DST) is specified | |

* in TZ; otherwise, 0. Default value is 1. | |

* timezone Difference in seconds between coordinated universal | |

* time and local time. E.g., -28,800 for PST (GMT-8hrs) | |

* tzname(0) Three-letter time-zone name derived from TZ environment | |

* variable. E.g., "PST". | |

* tzname(1) Three-letter DST zone name derived from TZ environment | |

* variable. E.g., "PDT". If DST zone is omitted from TZ, | |

* tzname(1) is an empty string. | |

* | |

* Notes: For example, to set the TZ environment variable to correspond | |

* to the current time zone in Germany, you can use one of the | |

* following statements: | |

* | |

* set TZ=GST1GDT | |

* set TZ=GST+1GDT | |

* | |

* If the TZ value is not set, t_tzset() attempts to use the time zone | |

* information specified by the operating system. Under Windows NT | |

* and Windows 95, this information is specified in the Control Panel's | |

* Date/Time application. | |

* @internal | |

*/ | |

U_INTERNAL void U_EXPORT2 uprv_tzset(void); | |

/** | |

* Difference in seconds between coordinated universal | |

* time and local time. E.g., -28,800 for PST (GMT-8hrs) | |

* @return the difference in seconds between coordinated universal time and local time. | |

* @internal | |

*/ | |

U_INTERNAL int32_t U_EXPORT2 uprv_timezone(void); | |

/** | |

* tzname(0) Three-letter time-zone name derived from TZ environment | |

* variable. E.g., "PST". | |

* tzname(1) Three-letter DST zone name derived from TZ environment | |

* variable. E.g., "PDT". If DST zone is omitted from TZ, | |

* tzname(1) is an empty string. | |

* @internal | |

*/ | |

U_INTERNAL const char* U_EXPORT2 uprv_tzname(int n); | |

/** | |

* Get UTC (GMT) time measured in milliseconds since 0:00 on 1/1/1970. | |

* @return the UTC time measured in milliseconds | |

* @internal | |

*/ | |

U_INTERNAL UDate U_EXPORT2 uprv_getUTCtime(void); | |

/** | |

* Determine whether a pathname is absolute or not, as defined by the platform. | |

* @param path Pathname to test | |

* @return TRUE if the path is absolute | |

* @internal (ICU 3.0) | |

*/ | |

U_INTERNAL UBool U_EXPORT2 uprv_pathIsAbsolute(const char *path); | |

/** | |

* Maximum value of a (void*) - use to indicate the limit of an 'infinite' buffer. | |

* In fact, buffer sizes must not exceed 2GB so that the difference between | |

* the buffer limit and the buffer start can be expressed in an int32_t. | |

* | |

* The definition of U_MAX_PTR must fulfill the following conditions: | |

* - return the largest possible pointer greater than base | |

* - return a valid pointer according to the machine architecture (AS/400, 64-bit, etc.) | |

* - avoid wrapping around at high addresses | |

* - make sure that the returned pointer is not farther from base than 0x7fffffff | |

* | |

* @param base The beginning of a buffer to find the maximum offset from | |

* @internal | |

*/ | |

#ifndef U_MAX_PTR | |

# ifdef OS390 | |

# define U_MAX_PTR(base) ((void *)0x7fffffff) | |

# elif defined(OS400) | |

/* | |

* With the provided macro we should never be out of range of a given segment | |

* (a traditional/typical segment that is). Our segments have 5 bytes for the id | |

* and 3 bytes for the offset. The key is that the casting takes care of only | |

* retrieving the offset portion minus x1000. Hence, the smallest offset seen in | |

* a program is x001000 and when casted to an int would be 0. That's why we can | |

* only add 0xffefff. Otherwise, we would exceed the segment. | |

* | |

* Currently, 16MB is the current addressing limitation on as/400. This macro | |

* may eventually be changed to use 2GB addressability for the newer version of | |

* as/400 machines. | |

*/ | |

# define U_MAX_PTR(base) ((void *)(((char *)base)-((int32_t)(base))+((int32_t)0xffefff))) | |

# else | |

# define U_MAX_PTR(base) ((void *)(((char *)(base)+0x7fffffffu) > (char *)(base) ? ((char *)(base)+0x7fffffffu) : (char *)-1)) | |

# endif | |

#endif | |

#endif |