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https://github.com/safing/portbase
synced 2025-09-01 10:09:50 +00:00
Merge pull request #127 from safing/fix/renameio
Fork renameio to fix build process
This commit is contained in:
commit
e0aca381f6
15 changed files with 692 additions and 19 deletions
|
@ -19,8 +19,7 @@ import (
|
|||
"github.com/safing/portbase/database/query"
|
||||
"github.com/safing/portbase/database/record"
|
||||
"github.com/safing/portbase/database/storage"
|
||||
|
||||
"github.com/google/renameio"
|
||||
"github.com/safing/portbase/utils/renameio"
|
||||
)
|
||||
|
||||
const (
|
||||
|
|
5
go.mod
5
go.mod
|
@ -38,8 +38,3 @@ require (
|
|||
google.golang.org/protobuf v1.25.0 // indirect
|
||||
gopkg.in/yaml.v3 v3.0.0-20200615113413-eeeca48fe776 // indirect
|
||||
)
|
||||
|
||||
// The follow-up commit removes Windows support.
|
||||
// TODO: Check how we want to handle this in the future, possibly ingest
|
||||
// needed functionality into here.
|
||||
require github.com/google/renameio v0.1.1-0.20200217212219-353f81969824
|
||||
|
|
2
go.sum
2
go.sum
|
@ -110,8 +110,6 @@ github.com/google/martian v2.1.0+incompatible/go.mod h1:9I4somxYTbIHy5NJKHRl3wXi
|
|||
github.com/google/pprof v0.0.0-20181206194817-3ea8567a2e57/go.mod h1:zfwlbNMJ+OItoe0UupaVj+oy1omPYYDuagoSzA8v9mc=
|
||||
github.com/google/pprof v0.0.0-20190515194954-54271f7e092f/go.mod h1:zfwlbNMJ+OItoe0UupaVj+oy1omPYYDuagoSzA8v9mc=
|
||||
github.com/google/renameio v0.1.0/go.mod h1:KWCgfxg9yswjAJkECMjeO8J8rahYeXnNhOm40UhjYkI=
|
||||
github.com/google/renameio v0.1.1-0.20200217212219-353f81969824 h1:9q700G0beHecUuiZOuKgNqNsGQixTeDLnzVZ5nsW3lc=
|
||||
github.com/google/renameio v0.1.1-0.20200217212219-353f81969824/go.mod h1:t/HQoYBZSsWSNK35C6CO/TpPLDVWvxOHboWUAweKUpk=
|
||||
github.com/googleapis/gax-go/v2 v2.0.4/go.mod h1:0Wqv26UfaUD9n4G6kQubkQ+KchISgw+vpHVxEJEs9eg=
|
||||
github.com/googleapis/gax-go/v2 v2.0.5/go.mod h1:DWXyrwAJ9X0FpwwEdw+IPEYBICEFu5mhpdKc/us6bOk=
|
||||
github.com/gopherjs/gopherjs v0.0.0-20181017120253-0766667cb4d1/go.mod h1:wJfORRmW1u3UXTncJ5qlYoELFm8eSnnEO6hX4iZ3EWY=
|
||||
|
|
|
@ -58,7 +58,7 @@ func prioritizedTaskTester(s string) {
|
|||
qtOutputChannel <- s
|
||||
qtWg.Done()
|
||||
return nil
|
||||
}).Prioritize()
|
||||
}).QueuePrioritized()
|
||||
}
|
||||
|
||||
// test
|
||||
|
@ -201,7 +201,7 @@ func TestRequeueingTask(t *testing.T) {
|
|||
// reschedule
|
||||
task.Schedule(time.Now().Add(1 * time.Second))
|
||||
task.Queue()
|
||||
task.Prioritize()
|
||||
task.QueuePrioritized()
|
||||
task.StartASAP()
|
||||
wg.Wait()
|
||||
time.Sleep(100 * time.Millisecond) // let tasks finalize execution
|
||||
|
@ -217,7 +217,7 @@ func TestRequeueingTask(t *testing.T) {
|
|||
wg.Add(1)
|
||||
task.Schedule(time.Now().Add(1 * time.Second))
|
||||
task.Queue()
|
||||
task.Prioritize()
|
||||
task.QueuePrioritized()
|
||||
task.StartASAP()
|
||||
wg.Wait()
|
||||
}
|
||||
|
|
|
@ -12,9 +12,8 @@ import (
|
|||
"path/filepath"
|
||||
"time"
|
||||
|
||||
"github.com/google/renameio"
|
||||
|
||||
"github.com/safing/portbase/log"
|
||||
"github.com/safing/portbase/utils/renameio"
|
||||
)
|
||||
|
||||
func (reg *ResourceRegistry) fetchFile(ctx context.Context, client *http.Client, rv *ResourceVersion, tries int) error {
|
||||
|
|
|
@ -5,11 +5,7 @@ import (
|
|||
"io"
|
||||
"os"
|
||||
|
||||
// Version is fixed to commit 353f8196982447d8b12c64f69530e657331e3dbc.
|
||||
// The follow-up commit removes Windows support.
|
||||
// TOOD: Check how we want to handle this in the future, possibly ingest
|
||||
// needed functionality into here.
|
||||
"github.com/google/renameio"
|
||||
"github.com/safing/portbase/utils/renameio"
|
||||
)
|
||||
|
||||
// AtomicFileOptions holds additional options for manipulating
|
||||
|
|
202
utils/renameio/LICENSE
Normal file
202
utils/renameio/LICENSE
Normal file
|
@ -0,0 +1,202 @@
|
|||
|
||||
Apache License
|
||||
Version 2.0, January 2004
|
||||
http://www.apache.org/licenses/
|
||||
|
||||
TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
|
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1. Definitions.
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"License" shall mean the terms and conditions for use, reproduction,
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and distribution as defined by Sections 1 through 9 of this document.
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"Work" shall mean the work of authorship, whether in Source or
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(d) If the Work includes a "NOTICE" text file as part of its
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of the NOTICE file are for informational purposes only and
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do not modify the License. You may add Your own attribution
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or as an addendum to the NOTICE text from the Work, provided
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You may add Your own copyright statement to Your modifications and
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for any such Derivative Works as a whole, provided Your use,
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reproduction, and distribution of the Work otherwise complies with
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the conditions stated in this License.
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5. Submission of Contributions. Unless You explicitly state otherwise,
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any Contribution intentionally submitted for inclusion in the Work
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by You to the Licensor shall be under the terms and conditions of
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this License, without any additional terms or conditions.
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Notwithstanding the above, nothing herein shall supersede or modify
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the terms of any separate license agreement you may have executed
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with Licensor regarding such Contributions.
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6. Trademarks. This License does not grant permission to use the trade
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7. Disclaimer of Warranty. Unless required by applicable law or
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Contributor provides its Contributions) on an "AS IS" BASIS,
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APPENDIX: How to apply the Apache License to your work.
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To apply the Apache License to your work, attach the following
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Licensed under the Apache License, Version 2.0 (the "License");
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You may obtain a copy of the License at
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Unless required by applicable law or agreed to in writing, software
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See the License for the specific language governing permissions and
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limitations under the License.
|
55
utils/renameio/README.md
Normal file
55
utils/renameio/README.md
Normal file
|
@ -0,0 +1,55 @@
|
|||
This is a fork of the github.com/google/renameio Go package at commit 353f8196982447d8b12c64f69530e657331e3dbc.
|
||||
|
||||
The inital commit of this package will carry the original package contents.
|
||||
The Original License is the Apache License in Version 2.0 and the copyright of the forked package is held by Google Inc.
|
||||
Any changes are recorded in the git history, which is part of this project.
|
||||
|
||||
---
|
||||
|
||||
The `renameio` Go package provides a way to atomically create or replace a file or
|
||||
symbolic link.
|
||||
|
||||
## Atomicity vs durability
|
||||
|
||||
`renameio` concerns itself *only* with atomicity, i.e. making sure applications
|
||||
never see unexpected file content (a half-written file, or a 0-byte file).
|
||||
|
||||
As a practical example, consider https://manpages.debian.org/: if there is a
|
||||
power outage while the site is updating, we are okay with losing the manpages
|
||||
which were being rendered at the time of the power outage. They will be added in
|
||||
a later run of the software. We are not okay with having a manpage replaced by a
|
||||
0-byte file under any circumstances, though.
|
||||
|
||||
## Advantages of this package
|
||||
|
||||
There are other packages for atomically replacing files, and sometimes ad-hoc
|
||||
implementations can be found in programs.
|
||||
|
||||
A naive approach to the problem is to create a temporary file followed by a call
|
||||
to `os.Rename()`. However, there are a number of subtleties which make the
|
||||
correct sequence of operations hard to identify:
|
||||
|
||||
* The temporary file should be removed when an error occurs, but a remove must
|
||||
not be attempted if the rename succeeded, as a new file might have been
|
||||
created with the same name. This renders a throwaway `defer
|
||||
os.Remove(t.Name())` insufficient; state must be kept.
|
||||
|
||||
* The temporary file must be created on the same file system (same mount point)
|
||||
for the rename to work, but the TMPDIR environment variable should still be
|
||||
respected, e.g. to direct temporary files into a separate directory outside of
|
||||
the webserver’s document root but on the same file system.
|
||||
|
||||
* On POSIX operating systems, the
|
||||
[`fsync`](https://manpages.debian.org/stretch/manpages-dev/fsync.2) system
|
||||
call must be used to ensure that the `os.Rename()` call will not result in a
|
||||
0-length file.
|
||||
|
||||
This package attempts to get all of these details right, provides an intuitive,
|
||||
yet flexible API and caters to use-cases where high performance is required.
|
||||
|
||||
## Disclaimer
|
||||
|
||||
This is not an official Google product (experimental or otherwise), it
|
||||
is just code that happens to be owned by Google.
|
||||
|
||||
This project is not affiliated with the Go project.
|
7
utils/renameio/doc.go
Normal file
7
utils/renameio/doc.go
Normal file
|
@ -0,0 +1,7 @@
|
|||
// Package renameio provides a way to atomically create or replace a file or
|
||||
// symbolic link.
|
||||
//
|
||||
// Caveat: this package requires the file system rename(2) implementation to be
|
||||
// atomic. Notably, this is not the case when using NFS with multiple clients:
|
||||
// https://stackoverflow.com/a/41396801
|
||||
package renameio
|
53
utils/renameio/example_test.go
Normal file
53
utils/renameio/example_test.go
Normal file
|
@ -0,0 +1,53 @@
|
|||
package renameio_test
|
||||
|
||||
import (
|
||||
"fmt"
|
||||
"log"
|
||||
|
||||
"github.com/safing/portbase/utils/renameio"
|
||||
)
|
||||
|
||||
func ExampleTempFile_justone() {
|
||||
persist := func(temperature float64) error {
|
||||
t, err := renameio.TempFile("", "/srv/www/metrics.txt")
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
defer t.Cleanup()
|
||||
if _, err := fmt.Fprintf(t, "temperature_degc %f\n", temperature); err != nil {
|
||||
return err
|
||||
}
|
||||
return t.CloseAtomicallyReplace()
|
||||
}
|
||||
// Thanks to the write package, a webserver exposing /srv/www never
|
||||
// serves an incomplete or missing file.
|
||||
if err := persist(31.2); err != nil {
|
||||
log.Fatal(err)
|
||||
}
|
||||
}
|
||||
|
||||
func ExampleTempFile_many() {
|
||||
// Prepare for writing files to /srv/www, effectively caching calls to
|
||||
// TempDir which TempFile would otherwise need to make.
|
||||
dir := renameio.TempDir("/srv/www")
|
||||
persist := func(temperature float64) error {
|
||||
t, err := renameio.TempFile(dir, "/srv/www/metrics.txt")
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
defer t.Cleanup()
|
||||
if _, err := fmt.Fprintf(t, "temperature_degc %f\n", temperature); err != nil {
|
||||
return err
|
||||
}
|
||||
return t.CloseAtomicallyReplace()
|
||||
}
|
||||
|
||||
// Imagine this was an endless loop, reading temperature sensor values.
|
||||
// Thanks to the write package, a webserver exposing /srv/www never
|
||||
// serves an incomplete or missing file.
|
||||
for {
|
||||
if err := persist(31.2); err != nil {
|
||||
log.Fatal(err)
|
||||
}
|
||||
}
|
||||
}
|
38
utils/renameio/symlink_test.go
Normal file
38
utils/renameio/symlink_test.go
Normal file
|
@ -0,0 +1,38 @@
|
|||
// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris windows
|
||||
|
||||
package renameio
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"io/ioutil"
|
||||
"os"
|
||||
"path/filepath"
|
||||
"testing"
|
||||
)
|
||||
|
||||
func TestSymlink(t *testing.T) {
|
||||
d, err := ioutil.TempDir("", "tempdirtest")
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
defer os.RemoveAll(d)
|
||||
|
||||
want := []byte("Hello World")
|
||||
if err := ioutil.WriteFile(filepath.Join(d, "hello.txt"), want, 0644); err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
|
||||
for i := 0; i < 2; i++ {
|
||||
if err := Symlink("hello.txt", filepath.Join(d, "hi.txt")); err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
|
||||
got, err := ioutil.ReadFile(filepath.Join(d, "hi.txt"))
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
if !bytes.Equal(got, want) {
|
||||
t.Fatalf("unexpected content: got %q, want %q", string(got), string(want))
|
||||
}
|
||||
}
|
||||
}
|
167
utils/renameio/tempfile.go
Normal file
167
utils/renameio/tempfile.go
Normal file
|
@ -0,0 +1,167 @@
|
|||
package renameio
|
||||
|
||||
import (
|
||||
"io/ioutil"
|
||||
"os"
|
||||
"path/filepath"
|
||||
)
|
||||
|
||||
// TempDir checks whether os.TempDir() can be used as a temporary directory for
|
||||
// later atomically replacing files within dest. If no (os.TempDir() resides on
|
||||
// a different mount point), dest is returned.
|
||||
//
|
||||
// Note that the returned value ceases to be valid once either os.TempDir()
|
||||
// changes (e.g. on Linux, once the TMPDIR environment variable changes) or the
|
||||
// file system is unmounted.
|
||||
func TempDir(dest string) string {
|
||||
return tempDir("", filepath.Join(dest, "renameio-TempDir"))
|
||||
}
|
||||
|
||||
func tempDir(dir, dest string) string {
|
||||
if dir != "" {
|
||||
return dir // caller-specified directory always wins
|
||||
}
|
||||
|
||||
// Chose the destination directory as temporary directory so that we
|
||||
// definitely can rename the file, for which both temporary and destination
|
||||
// file need to point to the same mount point.
|
||||
fallback := filepath.Dir(dest)
|
||||
|
||||
// The user might have overridden the os.TempDir() return value by setting
|
||||
// the TMPDIR environment variable.
|
||||
tmpdir := os.TempDir()
|
||||
|
||||
testsrc, err := ioutil.TempFile(tmpdir, "."+filepath.Base(dest))
|
||||
if err != nil {
|
||||
return fallback
|
||||
}
|
||||
cleanup := true
|
||||
defer func() {
|
||||
if cleanup {
|
||||
os.Remove(testsrc.Name())
|
||||
}
|
||||
}()
|
||||
testsrc.Close()
|
||||
|
||||
testdest, err := ioutil.TempFile(filepath.Dir(dest), "."+filepath.Base(dest))
|
||||
if err != nil {
|
||||
return fallback
|
||||
}
|
||||
defer os.Remove(testdest.Name())
|
||||
testdest.Close()
|
||||
|
||||
if err := os.Rename(testsrc.Name(), testdest.Name()); err != nil {
|
||||
return fallback
|
||||
}
|
||||
cleanup = false // testsrc no longer exists
|
||||
return tmpdir
|
||||
}
|
||||
|
||||
// PendingFile is a pending temporary file, waiting to replace the destination
|
||||
// path in a call to CloseAtomicallyReplace.
|
||||
type PendingFile struct {
|
||||
*os.File
|
||||
|
||||
path string
|
||||
done bool
|
||||
closed bool
|
||||
}
|
||||
|
||||
// Cleanup is a no-op if CloseAtomicallyReplace succeeded, and otherwise closes
|
||||
// and removes the temporary file.
|
||||
func (t *PendingFile) Cleanup() error {
|
||||
if t.done {
|
||||
return nil
|
||||
}
|
||||
// An error occurred. Close and remove the tempfile. Errors are returned for
|
||||
// reporting, there is nothing the caller can recover here.
|
||||
var closeErr error
|
||||
if !t.closed {
|
||||
closeErr = t.Close()
|
||||
}
|
||||
if err := os.Remove(t.Name()); err != nil {
|
||||
return err
|
||||
}
|
||||
return closeErr
|
||||
}
|
||||
|
||||
// CloseAtomicallyReplace closes the temporary file and atomically replaces
|
||||
// the destination file with it, i.e., a concurrent open(2) call will either
|
||||
// open the file previously located at the destination path (if any), or the
|
||||
// just written file, but the file will always be present.
|
||||
func (t *PendingFile) CloseAtomicallyReplace() error {
|
||||
// Even on an ordered file system (e.g. ext4 with data=ordered) or file
|
||||
// systems with write barriers, we cannot skip the fsync(2) call as per
|
||||
// Theodore Ts'o (ext2/3/4 lead developer):
|
||||
//
|
||||
// > data=ordered only guarantees the avoidance of stale data (e.g., the previous
|
||||
// > contents of a data block showing up after a crash, where the previous data
|
||||
// > could be someone's love letters, medical records, etc.). Without the fsync(2)
|
||||
// > a zero-length file is a valid and possible outcome after the rename.
|
||||
if err := t.Sync(); err != nil {
|
||||
return err
|
||||
}
|
||||
t.closed = true
|
||||
if err := t.Close(); err != nil {
|
||||
return err
|
||||
}
|
||||
if err := os.Rename(t.Name(), t.path); err != nil {
|
||||
return err
|
||||
}
|
||||
t.done = true
|
||||
return nil
|
||||
}
|
||||
|
||||
// TempFile wraps ioutil.TempFile for the use case of atomically creating or
|
||||
// replacing the destination file at path.
|
||||
//
|
||||
// If dir is the empty string, TempDir(filepath.Base(path)) is used. If you are
|
||||
// going to write a large number of files to the same file system, store the
|
||||
// result of TempDir(filepath.Base(path)) and pass it instead of the empty
|
||||
// string.
|
||||
//
|
||||
// The file's permissions will be 0600 by default. You can change these by
|
||||
// explicitly calling Chmod on the returned PendingFile.
|
||||
func TempFile(dir, path string) (*PendingFile, error) {
|
||||
f, err := ioutil.TempFile(tempDir(dir, path), "."+filepath.Base(path))
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
return &PendingFile{File: f, path: path}, nil
|
||||
}
|
||||
|
||||
// Symlink wraps os.Symlink, replacing an existing symlink with the same name
|
||||
// atomically (os.Symlink fails when newname already exists, at least on Linux).
|
||||
func Symlink(oldname, newname string) error {
|
||||
// Fast path: if newname does not exist yet, we can skip the whole dance
|
||||
// below.
|
||||
if err := os.Symlink(oldname, newname); err == nil || !os.IsExist(err) {
|
||||
return err
|
||||
}
|
||||
|
||||
// We need to use ioutil.TempDir, as we cannot overwrite a ioutil.TempFile,
|
||||
// and removing+symlinking creates a TOCTOU race.
|
||||
d, err := ioutil.TempDir(filepath.Dir(newname), "."+filepath.Base(newname))
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
cleanup := true
|
||||
defer func() {
|
||||
if cleanup {
|
||||
os.RemoveAll(d)
|
||||
}
|
||||
}()
|
||||
|
||||
symlink := filepath.Join(d, "tmp.symlink")
|
||||
if err := os.Symlink(oldname, symlink); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
if err := os.Rename(symlink, newname); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
cleanup = false
|
||||
return os.RemoveAll(d)
|
||||
}
|
97
utils/renameio/tempfile_linux_test.go
Normal file
97
utils/renameio/tempfile_linux_test.go
Normal file
|
@ -0,0 +1,97 @@
|
|||
// +build linux
|
||||
|
||||
package renameio
|
||||
|
||||
import (
|
||||
"io/ioutil"
|
||||
"os"
|
||||
"path/filepath"
|
||||
"syscall"
|
||||
"testing"
|
||||
)
|
||||
|
||||
func TestTempDir(t *testing.T) {
|
||||
if tmpdir, ok := os.LookupEnv("TMPDIR"); ok {
|
||||
defer os.Setenv("TMPDIR", tmpdir) // restore
|
||||
} else {
|
||||
defer os.Unsetenv("TMPDIR") // restore
|
||||
}
|
||||
|
||||
mount1, err := ioutil.TempDir("", "tempdirtest")
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
defer os.RemoveAll(mount1)
|
||||
|
||||
mount2, err := ioutil.TempDir("", "tempdirtest")
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
defer os.RemoveAll(mount2)
|
||||
|
||||
if err := syscall.Mount("tmpfs", mount1, "tmpfs", 0, ""); err != nil {
|
||||
t.Skipf("cannot mount tmpfs on %s: %v", mount1, err)
|
||||
}
|
||||
defer syscall.Unmount(mount1, 0)
|
||||
|
||||
if err := syscall.Mount("tmpfs", mount2, "tmpfs", 0, ""); err != nil {
|
||||
t.Skipf("cannot mount tmpfs on %s: %v", mount2, err)
|
||||
}
|
||||
defer syscall.Unmount(mount2, 0)
|
||||
|
||||
tests := []struct {
|
||||
name string
|
||||
dir string
|
||||
path string
|
||||
TMPDIR string
|
||||
want string
|
||||
}{
|
||||
{
|
||||
name: "implicit TMPDIR",
|
||||
path: filepath.Join(os.TempDir(), "foo.txt"),
|
||||
want: os.TempDir(),
|
||||
},
|
||||
|
||||
{
|
||||
name: "explicit TMPDIR",
|
||||
path: filepath.Join(mount1, "foo.txt"),
|
||||
TMPDIR: mount1,
|
||||
want: mount1,
|
||||
},
|
||||
|
||||
{
|
||||
name: "explicit unsuitable TMPDIR",
|
||||
path: filepath.Join(mount1, "foo.txt"),
|
||||
TMPDIR: mount2,
|
||||
want: mount1,
|
||||
},
|
||||
|
||||
{
|
||||
name: "nonexistant TMPDIR",
|
||||
path: filepath.Join(mount1, "foo.txt"),
|
||||
TMPDIR: "/nonexistant",
|
||||
want: mount1,
|
||||
},
|
||||
|
||||
{
|
||||
name: "caller-specified",
|
||||
dir: "/overridden",
|
||||
path: filepath.Join(mount1, "foo.txt"),
|
||||
TMPDIR: "/nonexistant",
|
||||
want: "/overridden",
|
||||
},
|
||||
}
|
||||
|
||||
for _, tt := range tests {
|
||||
t.Run(tt.name, func(t *testing.T) {
|
||||
if tt.TMPDIR == "" {
|
||||
os.Unsetenv("TMPDIR")
|
||||
} else {
|
||||
os.Setenv("TMPDIR", tt.TMPDIR)
|
||||
}
|
||||
if got := tempDir(tt.dir, tt.path); got != tt.want {
|
||||
t.Fatalf("tempDir(%q, %q): got %q, want %q", tt.dir, tt.path, got, tt.want)
|
||||
}
|
||||
})
|
||||
}
|
||||
}
|
24
utils/renameio/writefile.go
Normal file
24
utils/renameio/writefile.go
Normal file
|
@ -0,0 +1,24 @@
|
|||
package renameio
|
||||
|
||||
import "os"
|
||||
|
||||
// WriteFile mirrors ioutil.WriteFile, replacing an existing file with the same
|
||||
// name atomically.
|
||||
func WriteFile(filename string, data []byte, perm os.FileMode) error {
|
||||
t, err := TempFile("", filename)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
defer t.Cleanup()
|
||||
|
||||
// Set permissions before writing data, in case the data is sensitive.
|
||||
if err := t.Chmod(perm); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
if _, err := t.Write(data); err != nil {
|
||||
return err
|
||||
}
|
||||
|
||||
return t.CloseAtomicallyReplace()
|
||||
}
|
43
utils/renameio/writefile_test.go
Normal file
43
utils/renameio/writefile_test.go
Normal file
|
@ -0,0 +1,43 @@
|
|||
// +build darwin dragonfly freebsd linux nacl netbsd openbsd solaris windows
|
||||
|
||||
package renameio
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"io/ioutil"
|
||||
"os"
|
||||
"path/filepath"
|
||||
"testing"
|
||||
)
|
||||
|
||||
func TestWriteFile(t *testing.T) {
|
||||
d, err := ioutil.TempDir("", "tempdirtest")
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
defer os.RemoveAll(d)
|
||||
|
||||
filename := filepath.Join(d, "hello.sh")
|
||||
|
||||
wantData := []byte("#!/bin/sh\necho \"Hello World\"\n")
|
||||
wantPerm := os.FileMode(0755)
|
||||
if err := WriteFile(filename, wantData, wantPerm); err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
|
||||
gotData, err := ioutil.ReadFile(filename)
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
if !bytes.Equal(gotData, wantData) {
|
||||
t.Errorf("got data %v, want data %v", gotData, wantData)
|
||||
}
|
||||
|
||||
fi, err := os.Stat(filename)
|
||||
if err != nil {
|
||||
t.Fatal(err)
|
||||
}
|
||||
if gotPerm := fi.Mode() & os.ModePerm; gotPerm != wantPerm {
|
||||
t.Errorf("got permissions 0%o, want permissions 0%o", gotPerm, wantPerm)
|
||||
}
|
||||
}
|
Loading…
Add table
Reference in a new issue