podman

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// Go support for Protocol Buffers - Google's data interchange format
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//
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// Copyright 2016 The Go Authors.  All rights reserved.
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// https://github.com/golang/protobuf
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//
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// Redistribution and use in source and binary forms, with or without
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// modification, are permitted provided that the following conditions are
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// met:
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//
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//     * Redistributions of source code must retain the above copyright
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// notice, this list of conditions and the following disclaimer.
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//     * Redistributions in binary form must reproduce the above
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// copyright notice, this list of conditions and the following disclaimer
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// in the documentation and/or other materials provided with the
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// distribution.
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//     * Neither the name of Google Inc. nor the names of its
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// contributors may be used to endorse or promote products derived from
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// this software without specific prior written permission.
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//
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// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
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// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
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// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
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// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
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// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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package proto
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// This file implements operations on google.protobuf.Timestamp.
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import (
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	"errors"
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	"fmt"
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	"time"
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)
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const (
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	// Seconds field of the earliest valid Timestamp.
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	// This is time.Date(1, 1, 1, 0, 0, 0, 0, time.UTC).Unix().
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	minValidSeconds = -62135596800
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	// Seconds field just after the latest valid Timestamp.
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	// This is time.Date(10000, 1, 1, 0, 0, 0, 0, time.UTC).Unix().
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	maxValidSeconds = 253402300800
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)
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// validateTimestamp determines whether a Timestamp is valid.
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// A valid timestamp represents a time in the range
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// [0001-01-01, 10000-01-01) and has a Nanos field
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// in the range [0, 1e9).
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//
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// If the Timestamp is valid, validateTimestamp returns nil.
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// Otherwise, it returns an error that describes
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// the problem.
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//
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// Every valid Timestamp can be represented by a time.Time, but the converse is not true.
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func validateTimestamp(ts *timestamp) error {
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	if ts == nil {
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		return errors.New("timestamp: nil Timestamp")
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	}
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	if ts.Seconds < minValidSeconds {
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		return fmt.Errorf("timestamp: %#v before 0001-01-01", ts)
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	}
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	if ts.Seconds >= maxValidSeconds {
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		return fmt.Errorf("timestamp: %#v after 10000-01-01", ts)
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	}
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	if ts.Nanos < 0 || ts.Nanos >= 1e9 {
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		return fmt.Errorf("timestamp: %#v: nanos not in range [0, 1e9)", ts)
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	}
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	return nil
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}
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// TimestampFromProto converts a google.protobuf.Timestamp proto to a time.Time.
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// It returns an error if the argument is invalid.
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//
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// Unlike most Go functions, if Timestamp returns an error, the first return value
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// is not the zero time.Time. Instead, it is the value obtained from the
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// time.Unix function when passed the contents of the Timestamp, in the UTC
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// locale. This may or may not be a meaningful time; many invalid Timestamps
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// do map to valid time.Times.
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//
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// A nil Timestamp returns an error. The first return value in that case is
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// undefined.
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func timestampFromProto(ts *timestamp) (time.Time, error) {
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	// Don't return the zero value on error, because corresponds to a valid
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	// timestamp. Instead return whatever time.Unix gives us.
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	var t time.Time
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	if ts == nil {
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		t = time.Unix(0, 0).UTC() // treat nil like the empty Timestamp
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	} else {
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		t = time.Unix(ts.Seconds, int64(ts.Nanos)).UTC()
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	}
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	return t, validateTimestamp(ts)
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}
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// TimestampProto converts the time.Time to a google.protobuf.Timestamp proto.
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// It returns an error if the resulting Timestamp is invalid.
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func timestampProto(t time.Time) (*timestamp, error) {
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	seconds := t.Unix()
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	nanos := int32(t.Sub(time.Unix(seconds, 0)))
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	ts := &timestamp{
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		Seconds: seconds,
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		Nanos:   nanos,
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	}
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	if err := validateTimestamp(ts); err != nil {
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		return nil, err
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	}
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	return ts, nil
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}
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