cubefs

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// Copyright 2019 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 util
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import (
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	"io"
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	"os"
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)
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// ReadFileNoStat uses io.ReadAll to read contents of entire file.
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// This is similar to os.ReadFile but without the call to os.Stat, because
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// many files in /proc and /sys report incorrect file sizes (either 0 or 4096).
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// Reads a max file size of 1024kB.  For files larger than this, a scanner
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// should be used.
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func ReadFileNoStat(filename string) ([]byte, error) {
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	const maxBufferSize = 1024 * 1024
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	f, err := os.Open(filename)
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	if err != nil {
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		return nil, err
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	}
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	defer f.Close()
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	reader := io.LimitReader(f, maxBufferSize)
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	return io.ReadAll(reader)
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}
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