1 //===-- TimeValue.h - Declare OS TimeValue Concept --------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This header file declares the operating system TimeValue concept.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/Support/DataTypes.h"
17 #ifndef LLVM_SYSTEM_TIMEVALUE_H
18 #define LLVM_SYSTEM_TIMEVALUE_H
22 /// This class is used where a precise fixed point in time is required. The
23 /// range of TimeValue spans many hundreds of billions of years both past and
24 /// present. The precision of TimeValue is to the nanosecond. However, the
25 /// actual precision of its values will be determined by the resolution of
26 /// the system clock. The TimeValue class is used in conjunction with several
27 /// other lib/System interfaces to specify the time at which a call should
30 /// @brief Provides an abstraction for a fixed point in time.
37 /// A constant TimeValue representing the smallest time
38 /// value permissible by the class. MinTime is some point
39 /// in the distant past, about 300 billion years BCE.
40 /// @brief The smallest possible time value.
41 static const TimeValue MinTime;
43 /// A constant TimeValue representing the largest time
44 /// value permissible by the class. MaxTime is some point
45 /// in the distant future, about 300 billion years AD.
46 /// @brief The largest possible time value.
47 static const TimeValue MaxTime;
49 /// A constant TimeValue representing the base time,
50 /// or zero time of 00:00:00 (midnight) January 1st, 2000.
51 /// @brief 00:00:00 Jan 1, 2000 UTC.
52 static const TimeValue ZeroTime;
54 /// A constant TimeValue for the Posix base time which is
55 /// 00:00:00 (midnight) January 1st, 1970.
56 /// @brief 00:00:00 Jan 1, 1970 UTC.
57 static const TimeValue PosixZeroTime;
59 /// A constant TimeValue for the Win32 base time which is
60 /// 00:00:00 (midnight) January 1st, 1601.
61 /// @brief 00:00:00 Jan 1, 1601 UTC.
62 static const TimeValue Win32ZeroTime;
68 typedef int64_t SecondsType; ///< Type used for representing seconds.
69 typedef int32_t NanoSecondsType;///< Type used for representing nanoseconds.
71 enum TimeConversions {
72 NANOSECONDS_PER_SECOND = 1000000000, ///< One Billion
73 MICROSECONDS_PER_SECOND = 1000000, ///< One Million
74 MILLISECONDS_PER_SECOND = 1000, ///< One Thousand
75 NANOSECONDS_PER_MICROSECOND = 1000, ///< One Thousand
76 NANOSECONDS_PER_MILLISECOND = 1000000,///< One Million
77 NANOSECONDS_PER_POSIX_TICK = 100, ///< Posix tick is 100 Hz (10ms)
78 NANOSECONDS_PER_WIN32_TICK = 100 ///< Win32 tick is 100 Hz (10ms)
82 /// @name Constructors
85 /// Caller provides the exact value in seconds and nanoseconds. The
86 /// \p nanos argument defaults to zero for convenience.
87 /// @brief Explicit constructor
88 explicit TimeValue (SecondsType seconds, NanoSecondsType nanos = 0)
89 : seconds_( seconds ), nanos_( nanos ) { this->normalize(); }
91 /// Caller provides the exact value as a double in seconds with the
92 /// fractional part representing nanoseconds.
93 /// @brief Double Constructor.
94 explicit TimeValue( double new_time )
95 : seconds_( 0 ) , nanos_ ( 0 ) {
96 SecondsType integer_part = static_cast<SecondsType>( new_time );
97 seconds_ = integer_part;
98 nanos_ = static_cast<NanoSecondsType>( (new_time -
99 static_cast<double>(integer_part)) * NANOSECONDS_PER_SECOND );
103 /// This is a static constructor that returns a TimeValue that represents
104 /// the current time.
105 /// @brief Creates a TimeValue with the current time (UTC).
106 static TimeValue now();
112 /// Add \p that to \p this.
114 /// @brief Incrementing assignment operator.
115 TimeValue& operator += (const TimeValue& that ) {
116 this->seconds_ += that.seconds_ ;
117 this->nanos_ += that.nanos_ ;
122 /// Subtract \p that from \p this.
124 /// @brief Decrementing assignment operator.
125 TimeValue& operator -= (const TimeValue &that ) {
126 this->seconds_ -= that.seconds_ ;
127 this->nanos_ -= that.nanos_ ;
132 /// Determine if \p this is less than \p that.
133 /// @returns True iff *this < that.
134 /// @brief True if this < that.
135 int operator < (const TimeValue &that) const { return that > *this; }
137 /// Determine if \p this is greather than \p that.
138 /// @returns True iff *this > that.
139 /// @brief True if this > that.
140 int operator > (const TimeValue &that) const {
141 if ( this->seconds_ > that.seconds_ ) {
143 } else if ( this->seconds_ == that.seconds_ ) {
144 if ( this->nanos_ > that.nanos_ ) return 1;
149 /// Determine if \p this is less than or equal to \p that.
150 /// @returns True iff *this <= that.
151 /// @brief True if this <= that.
152 int operator <= (const TimeValue &that) const { return that >= *this; }
154 /// Determine if \p this is greater than or equal to \p that.
155 /// @returns True iff *this >= that.
156 int operator >= (const TimeValue &that) const {
157 if ( this->seconds_ > that.seconds_ ) {
159 } else if ( this->seconds_ == that.seconds_ ) {
160 if ( this->nanos_ >= that.nanos_ ) return 1;
165 /// Determines if two TimeValue objects represent the same moment in time.
166 /// @returns True iff *this == that.
167 int operator == (const TimeValue &that) const {
168 return (this->seconds_ == that.seconds_) &&
169 (this->nanos_ == that.nanos_);
172 /// Determines if two TimeValue objects represent times that are not the
174 /// @returns True iff *this != that.
175 int operator != (const TimeValue &that) const { return !(*this == that); }
177 /// Adds two TimeValue objects together.
178 /// @returns The sum of the two operands as a new TimeValue
179 /// @brief Addition operator.
180 friend TimeValue operator + (const TimeValue &tv1, const TimeValue &tv2);
182 /// Subtracts two TimeValue objects.
183 /// @returns The difference of the two operands as a new TimeValue
184 /// @brief Subtraction operator.
185 friend TimeValue operator - (const TimeValue &tv1, const TimeValue &tv2);
192 /// Returns only the seconds component of the TimeValue. The nanoseconds
193 /// portion is ignored. No rounding is performed.
194 /// @brief Retrieve the seconds component
195 SecondsType seconds() const { return seconds_; }
197 /// Returns only the nanoseconds component of the TimeValue. The seconds
198 /// portion is ignored.
199 /// @brief Retrieve the nanoseconds component.
200 NanoSecondsType nanoseconds() const { return nanos_; }
202 /// Returns only the fractional portion of the TimeValue rounded down to the
203 /// nearest microsecond (divide by one thousand).
204 /// @brief Retrieve the fractional part as microseconds;
205 uint32_t microseconds() const {
206 return nanos_ / NANOSECONDS_PER_MICROSECOND;
209 /// Returns only the fractional portion of the TimeValue rounded down to the
210 /// nearest millisecond (divide by one million).
211 /// @brief Retrieve the fractional part as milliseconds;
212 uint32_t milliseconds() const {
213 return nanos_ / NANOSECONDS_PER_MILLISECOND;
216 /// Returns the TimeValue as a number of microseconds. Note that the value
217 /// returned can overflow because the range of a uint64_t is smaller than
218 /// the range of a TimeValue. Nevertheless, this is useful on some operating
219 /// systems and is therefore provided.
220 /// @brief Convert to a number of microseconds (can overflow)
221 uint64_t usec() const {
222 return seconds_ * MICROSECONDS_PER_SECOND +
223 ( nanos_ / NANOSECONDS_PER_MICROSECOND );
226 /// Returns the TimeValue as a number of milliseconds. Note that the value
227 /// returned can overflow because the range of a uint64_t is smaller than
228 /// the range of a TimeValue. Nevertheless, this is useful on some operating
229 /// systems and is therefore provided.
230 /// @brief Convert to a number of milliseconds (can overflow)
231 uint64_t msec() const {
232 return seconds_ * MILLISECONDS_PER_SECOND +
233 ( nanos_ / NANOSECONDS_PER_MILLISECOND );
236 /// Converts the TimeValue into the corresponding number of "ticks" for
237 /// Posix, correcting for the difference in Posix zero time.
238 /// @brief Convert to unix time (100 nanoseconds since 12:00:00a Jan 1,1970)
239 uint64_t toPosixTime() const {
240 uint64_t result = seconds_ - PosixZeroTime.seconds_;
241 result += nanos_ / NANOSECONDS_PER_POSIX_TICK;
245 /// Converts the TimeValue into the corresponding number of seconds
246 /// since the epoch (00:00:00 Jan 1,1970).
247 uint64_t toEpochTime() const {
248 return seconds_ - PosixZeroTime.seconds_;
251 /// Converts the TimeValue into the corresponding number of "ticks" for
252 /// Win32 platforms, correcting for the difference in Win32 zero time.
253 /// @brief Convert to windows time (seconds since 12:00:00a Jan 1, 1601)
254 uint64_t toWin32Time() const {
255 uint64_t result = seconds_ - Win32ZeroTime.seconds_;
256 result += nanos_ / NANOSECONDS_PER_WIN32_TICK;
260 /// Provides the seconds and nanoseconds as results in its arguments after
261 /// correction for the Posix zero time.
262 /// @brief Convert to timespec time (ala POSIX.1b)
263 void getTimespecTime( uint64_t& seconds, uint32_t& nanos ) const {
264 seconds = seconds_ - PosixZeroTime.seconds_;
268 /// Provides conversion of the TimeValue into a readable time & date.
269 /// @returns std::string containing the readable time value
270 /// @brief Convert time to a string.
271 std::string str() const;
277 /// The seconds component of the TimeValue is set to \p sec without
278 /// modifying the nanoseconds part. This is useful for whole second
280 /// @brief Set the seconds component.
281 void seconds (SecondsType sec ) {
282 this->seconds_ = sec;
286 /// The nanoseconds component of the TimeValue is set to \p nanos without
287 /// modifying the seconds part. This is useful for basic computations
288 /// involving just the nanoseconds portion. Note that the TimeValue will be
289 /// normalized after this call so that the fractional (nanoseconds) portion
290 /// will have the smallest equivalent value.
291 /// @brief Set the nanoseconds component using a number of nanoseconds.
292 void nanoseconds ( NanoSecondsType nanos ) {
293 this->nanos_ = nanos;
297 /// The seconds component remains unchanged.
298 /// @brief Set the nanoseconds component using a number of microseconds.
299 void microseconds ( int32_t micros ) {
300 this->nanos_ = micros * NANOSECONDS_PER_MICROSECOND;
304 /// The seconds component remains unchanged.
305 /// @brief Set the nanoseconds component using a number of milliseconds.
306 void milliseconds ( int32_t millis ) {
307 this->nanos_ = millis * NANOSECONDS_PER_MILLISECOND;
311 /// @brief Converts from microsecond format to TimeValue format
312 void usec( int64_t microseconds ) {
313 this->seconds_ = microseconds / MICROSECONDS_PER_SECOND;
314 this->nanos_ = NanoSecondsType(microseconds % MICROSECONDS_PER_SECOND) *
315 NANOSECONDS_PER_MICROSECOND;
319 /// @brief Converts from millisecond format to TimeValue format
320 void msec( int64_t milliseconds ) {
321 this->seconds_ = milliseconds / MILLISECONDS_PER_SECOND;
322 this->nanos_ = NanoSecondsType(milliseconds % MILLISECONDS_PER_SECOND) *
323 NANOSECONDS_PER_MILLISECOND;
327 /// Converts the \p seconds argument from PosixTime to the corresponding
328 /// TimeValue and assigns that value to \p this.
329 /// @brief Convert seconds form PosixTime to TimeValue
330 void fromEpochTime( SecondsType seconds ) {
331 seconds_ = seconds + PosixZeroTime.seconds_;
336 /// Converts the \p win32Time argument from Windows FILETIME to the
337 /// corresponding TimeValue and assigns that value to \p this.
338 /// @brief Convert seconds form Windows FILETIME to TimeValue
339 void fromWin32Time( uint64_t win32Time ) {
340 this->seconds_ = win32Time / 10000000 + Win32ZeroTime.seconds_;
341 this->nanos_ = NanoSecondsType(win32Time % 10000000) * 100;
345 /// @name Implementation
348 /// This causes the values to be represented so that the fractional
349 /// part is minimized, possibly incrementing the seconds part.
350 /// @brief Normalize to canonical form.
357 /// Store the values as a <timeval>.
358 SecondsType seconds_;///< Stores the seconds part of the TimeVal
359 NanoSecondsType nanos_; ///< Stores the nanoseconds part of the TimeVal
364 inline TimeValue operator + (const TimeValue &tv1, const TimeValue &tv2) {
365 TimeValue sum (tv1.seconds_ + tv2.seconds_, tv1.nanos_ + tv2.nanos_);
370 inline TimeValue operator - (const TimeValue &tv1, const TimeValue &tv2) {
371 TimeValue difference (tv1.seconds_ - tv2.seconds_, tv1.nanos_ - tv2.nanos_ );
372 difference.normalize ();