cubefs

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// Copyright 2018 The Prometheus Authors
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// Licensed under the Apache License, Version 2.0 (the "License");
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// you may not use this file except in compliance with the License.
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// You may obtain a copy of the License at
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//
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// http://www.apache.org/licenses/LICENSE-2.0
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//
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// Unless required by applicable law or agreed to in writing, software
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// distributed under the License is distributed on an "AS IS" BASIS,
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// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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// See the License for the specific language governing permissions and
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// limitations under the License.
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package procfs
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import (
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	"fmt"
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	"github.com/prometheus/procfs/internal/util"
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)
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// ProcIO models the content of /proc/<pid>/io.
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type ProcIO struct {
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	// Chars read.
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	RChar uint64
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	// Chars written.
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	WChar uint64
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	// Read syscalls.
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	SyscR uint64
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	// Write syscalls.
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	SyscW uint64
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	// Bytes read.
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	ReadBytes uint64
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	// Bytes written.
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	WriteBytes uint64
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	// Bytes written, but taking into account truncation. See
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	// Documentation/filesystems/proc.txt in the kernel sources for
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	// detailed explanation.
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	CancelledWriteBytes int64
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}
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// IO creates a new ProcIO instance from a given Proc instance.
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func (p Proc) IO() (ProcIO, error) {
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	pio := ProcIO{}
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	data, err := util.ReadFileNoStat(p.path("io"))
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	if err != nil {
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		return pio, err
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	}
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	ioFormat := "rchar: %d\nwchar: %d\nsyscr: %d\nsyscw: %d\n" +
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		"read_bytes: %d\nwrite_bytes: %d\n" +
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		"cancelled_write_bytes: %d\n"
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	_, err = fmt.Sscanf(string(data), ioFormat, &pio.RChar, &pio.WChar, &pio.SyscR,
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		&pio.SyscW, &pio.ReadBytes, &pio.WriteBytes, &pio.CancelledWriteBytes)
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	return pio, err
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}
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