blob: 8051161b2aa4da254827bb1580c90b3f88fec2b3 [file] [log] [blame]
khenaidoo26721882021-08-11 17:42:52 -04001// Copyright 2019 The Prometheus Authors
2// Licensed under the Apache License, Version 2.0 (the "License");
3// you may not use this file except in compliance with the License.
4// You may obtain a copy of the License at
5//
6// http://www.apache.org/licenses/LICENSE-2.0
7//
8// Unless required by applicable law or agreed to in writing, software
9// distributed under the License is distributed on an "AS IS" BASIS,
10// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
11// See the License for the specific language governing permissions and
12// limitations under the License.
13
14package util
15
16import (
17 "io"
18 "io/ioutil"
19 "os"
20)
21
22// ReadFileNoStat uses ioutil.ReadAll to read contents of entire file.
23// This is similar to ioutil.ReadFile but without the call to os.Stat, because
24// many files in /proc and /sys report incorrect file sizes (either 0 or 4096).
25// Reads a max file size of 512kB. For files larger than this, a scanner
26// should be used.
27func ReadFileNoStat(filename string) ([]byte, error) {
28 const maxBufferSize = 1024 * 512
29
30 f, err := os.Open(filename)
31 if err != nil {
32 return nil, err
33 }
34 defer f.Close()
35
36 reader := io.LimitReader(f, maxBufferSize)
37 return ioutil.ReadAll(reader)
38}