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Timestamps and Time Differences

This module defines microsecond- and millisecond-level timestamp types MicrosecondTimestamp and MillisecondTimestamp, which represent system clock times and can be used to compute the time difference between two points. It is suitable for scenarios such as timers, delay control, and performance analysis.

MicrosecondTimestamp​

class MicrosecondTimestamp {
 public:
  MicrosecondTimestamp();
  MicrosecondTimestamp(uint64_t microsecond);
  operator uint64_t() const;

  class Duration {
   public:
    Duration(uint64_t diff);
    operator uint64_t() const;
    double ToSecond() const;
    float ToSecondf() const;
    uint64_t ToMicrosecond() const;
    uint32_t ToMillisecond() const;
  };

  Duration operator-(const MicrosecondTimestamp& old) const;
  MicrosecondTimestamp& operator=(const MicrosecondTimestamp& other);
};

Represents a microsecond-level timestamp. Supports implicit conversion to uint64_t and can be used to compute time differences.

Duration​

MicrosecondTimestamp::Duration represents the time difference between two MicrosecondTimestamp instances, in microseconds. Supports conversion to seconds and milliseconds.

MillisecondTimestamp​

class MillisecondTimestamp {
 public:
  MillisecondTimestamp();
  MillisecondTimestamp(uint32_t millisecond);
  operator uint32_t() const;

  class Duration {
   public:
    Duration(uint32_t diff);
    operator uint32_t() const;
    double ToSecond() const;
    float ToSecondf() const;
    uint32_t ToMillisecond() const;
    uint64_t ToMicrosecond() const;
  };

  Duration operator-(const MillisecondTimestamp& old) const;
};

Represents a millisecond-level timestamp. Supports implicit conversion to uint32_t and can be used to compute time differences.

Duration​

MillisecondTimestamp::Duration represents the time difference between two MillisecondTimestamp instances, in milliseconds. Supports conversion to seconds and microseconds.

Overflow Handling​

Time difference computations handle timestamp wrap-around (e.g., overflow), making it suitable for system clock management on embedded platforms.

To adapt to different platforms/timebases, this module also exposes two timebase configuration values (used by the implementation layer):

extern uint64_t libxr_timebase_max_valid_us;
extern uint32_t libxr_timebase_max_valid_ms;

They specify the "maximum valid timebase value" (microseconds/milliseconds), so wrap-around difference calculations and validity checks can be performed correctly.

This module forms the basis of time handling in LibXR and can be used with IO, schedulers, timers, and other modules to ensure precision and portability in time-related operations.