vendor/github.com/golang/protobuf/ptypes/duration.go

   1 // Go support for Protocol Buffers - Google's data interchange format
   2 //
   3 // Copyright 2016 The Go Authors.  All rights reserved.
   4 // https://github.com/golang/protobuf
   5 //
   6 // Redistribution and use in source and binary forms, with or without
   7 // modification, are permitted provided that the following conditions are
   8 // met:
   9 //
  10 //     * Redistributions of source code must retain the above copyright
  11 // notice, this list of conditions and the following disclaimer.
  12 //     * Redistributions in binary form must reproduce the above
  13 // copyright notice, this list of conditions and the following disclaimer
  14 // in the documentation and/or other materials provided with the
  15 // distribution.
  16 //     * Neither the name of Google Inc. nor the names of its
  17 // contributors may be used to endorse or promote products derived from
  18 // this software without specific prior written permission.
  19 //
  20 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  21 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  22 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  23 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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  26 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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  29 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  30 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  31
  32 package ptypes
  33
  34 // This file implements conversions between google.protobuf.Duration
  35 // and time.Duration.
  36
  37 import (
  38         "errors"
  39         "fmt"
  40         "time"
  41
  42         durpb "github.com/golang/protobuf/ptypes/duration"
  43 )
  44
  45 const (
  46         // Range of a durpb.Duration in seconds, as specified in
  47         // google/protobuf/duration.proto. This is about 10,000 years in seconds.
  48         maxSeconds = int64(10000 * 365.25 * 24 * 60 * 60)
  49         minSeconds = -maxSeconds
  50 )
  51
  52 // validateDuration determines whether the durpb.Duration is valid according to the
  53 // definition in google/protobuf/duration.proto. A valid durpb.Duration
  54 // may still be too large to fit into a time.Duration (the range of durpb.Duration
  55 // is about 10,000 years, and the range of time.Duration is about 290).
  56 func validateDuration(d *durpb.Duration) error {
  57         if d == nil {
  58                 return errors.New("duration: nil Duration")
  59         }
  60         if d.Seconds < minSeconds || d.Seconds > maxSeconds {
  61                 return fmt.Errorf("duration: %v: seconds out of range", d)
  62         }
  63         if d.Nanos <= -1e9 || d.Nanos >= 1e9 {
  64                 return fmt.Errorf("duration: %v: nanos out of range", d)
  65         }
  66         // Seconds and Nanos must have the same sign, unless d.Nanos is zero.
  67         if (d.Seconds < 0 && d.Nanos > 0) || (d.Seconds > 0 && d.Nanos < 0) {
  68                 return fmt.Errorf("duration: %v: seconds and nanos have different signs", d)
  69         }
  70         return nil
  71 }
  72
  73 // Duration converts a durpb.Duration to a time.Duration. Duration
  74 // returns an error if the durpb.Duration is invalid or is too large to be
  75 // represented in a time.Duration.
  76 func Duration(p *durpb.Duration) (time.Duration, error) {
  77         if err := validateDuration(p); err != nil {
  78                 return 0, err
  79         }
  80         d := time.Duration(p.Seconds) * time.Second
  81         if int64(d/time.Second) != p.Seconds {
  82                 return 0, fmt.Errorf("duration: %v is out of range for time.Duration", p)
  83         }
  84         if p.Nanos != 0 {
  85                 d += time.Duration(p.Nanos) * time.Nanosecond
  86                 if (d < 0) != (p.Nanos < 0) {
  87                         return 0, fmt.Errorf("duration: %v is out of range for time.Duration", p)
  88                 }
  89         }
  90         return d, nil
  91 }
  92
  93 // DurationProto converts a time.Duration to a durpb.Duration.
  94 func DurationProto(d time.Duration) *durpb.Duration {
  95         nanos := d.Nanoseconds()
  96         secs := nanos / 1e9
  97         nanos -= secs * 1e9
  98         return &durpb.Duration{
  99                 Seconds: secs,
 100                 Nanos:   int32(nanos),
 101         }
 102 }