.github
alerting
client
config
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docs
example
jsonpath
k8s
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metric
pattern
security
static
vendor
cloud.google.com
github.com
beorn7
cespare
davecgh
gogo
golang
google
googleapis
imdario
json-iterator
matttproud
miekg
modern-go
prometheus
client_golang
client_model
common
procfs
internal
fs
util
parse.go
readfile.go
sysreadfile.go
sysreadfile_compat.go
valueparser.go
.gitignore
.golangci.yml
CONTRIBUTING.md
LICENSE
MAINTAINERS.md
Makefile
Makefile.common
NOTICE
README.md
arp.go
buddyinfo.go
cpuinfo.go
cpuinfo_arm.go
cpuinfo_arm64.go
cpuinfo_default.go
cpuinfo_mips.go
cpuinfo_mips64.go
cpuinfo_mips64le.go
cpuinfo_mipsle.go
cpuinfo_ppc64.go
cpuinfo_ppc64le.go
cpuinfo_s390x.go
crypto.go
doc.go
fixtures.ttar
fs.go
fscache.go
go.mod
go.sum
ipvs.go
kernel_random.go
loadavg.go
mdstat.go
meminfo.go
mountinfo.go
mountstats.go
net_conntrackstat.go
net_dev.go
net_sockstat.go
net_softnet.go
net_udp.go
net_unix.go
proc.go
proc_cgroup.go
proc_environ.go
proc_fdinfo.go
proc_io.go
proc_limits.go
proc_maps.go
proc_ns.go
proc_psi.go
proc_smaps.go
proc_stat.go
proc_status.go
schedstat.go
stat.go
swaps.go
ttar
vm.go
xfrm.go
zoneinfo.go
spf13
golang.org
google.golang.org
gopkg.in
k8s.io
sigs.k8s.io
modules.txt
watchdog
.dockerignore
.gitattributes
.gitignore
Dockerfile
LICENSE.md
README.md
config.yaml
go.mod
go.sum
gzip.go
main.go
49 lines
1.4 KiB
Go
49 lines
1.4 KiB
Go
// 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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// +build linux,!appengine
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package util
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import (
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"bytes"
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"os"
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"syscall"
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)
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// SysReadFile is a simplified ioutil.ReadFile that invokes syscall.Read directly.
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// https://github.com/prometheus/node_exporter/pull/728/files
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//
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// Note that this function will not read files larger than 128 bytes.
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func SysReadFile(file string) (string, error) {
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f, err := os.Open(file)
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if err != nil {
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return "", err
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}
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defer f.Close()
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// On some machines, hwmon drivers are broken and return EAGAIN. This causes
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// Go's ioutil.ReadFile implementation to poll forever.
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//
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// Since we either want to read data or bail immediately, do the simplest
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// possible read using syscall directly.
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const sysFileBufferSize = 128
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b := make([]byte, sysFileBufferSize)
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n, err := syscall.Read(int(f.Fd()), b)
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if err != nil {
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return "", err
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}
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return string(bytes.TrimSpace(b[:n])), nil
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}
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