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thaJeztahthaJeztah
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Merge pull request #49118 from thaJeztah/reexec_clean
pkg/reexec: some cleaning up in preparation of moving to a separate module
2 parents f237ba0 + 8fd177d commit cc1d50a

7 files changed

Lines changed: 60 additions & 66 deletions

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‎pkg/reexec/command_linux.go‎

Lines changed: 0 additions & 26 deletions
This file was deleted.

‎pkg/reexec/command_other.go‎

Lines changed: 0 additions & 19 deletions
This file was deleted.

‎pkg/reexec/command_unsupported.go‎

Lines changed: 0 additions & 12 deletions
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‎pkg/reexec/reexec.go‎

Lines changed: 24 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -3,7 +3,7 @@
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// Handlers can be registered with a name and the argv 0 of the exec of
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// the binary will be used to find and execute custom init paths.
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//
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// It is used in dockerd to work around forking limitations when using Go.
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// It is used to work around forking limitations when using Go.
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package reexec
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import (
@@ -36,10 +36,29 @@ func Init() bool {
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return false
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}
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// Self returns the path to the current process's binary. On Linux, it
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// returns "/proc/self/exe", which provides the in-memory version of the
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// current binary, whereas on other platforms it attempts to looks up the
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// absolute path for os.Args[0], or otherwise returns os.Args[0] as-is.
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// Command returns an [*exec.Cmd] with its Path set to the path of the current
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// binary using the result of [Self].
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//
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// On Linux, the Pdeathsig of [*exec.Cmd.SysProcAttr] is set to SIGTERM.
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// This signal is sent to the process when the OS thread that created
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// the process dies.
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//
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// It is the caller's responsibility to ensure that the creating thread is
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// not terminated prematurely. See https://go.dev/issue/27505 for more details.
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func Command(args ...string) *exec.Cmd {
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return command(args...)
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}
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// Self returns the path to the current process's binary.
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//
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// On Linux, it returns "/proc/self/exe", which provides the in-memory version
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// of the current binary. This makes it safe to delete or replace the on-disk
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// binary (os.Args[0]).
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//
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// On Other platforms, it attempts to look up the absolute path for os.Args[0],
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// or otherwise returns os.Args[0] as-is. For example if current binary is
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// "my-binary" at "/usr/bin/" (or "my-binary.exe" at "C:\" on Windows),
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// then it returns "/usr/bin/my-binary" and "C:\my-binary.exe" respectively.
4362
func Self() string {
4463
if runtime.GOOS == "linux" {
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return "/proc/self/exe"

‎pkg/reexec/reexec_linux.go‎

Lines changed: 16 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,16 @@
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package reexec
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import (
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"os/exec"
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"syscall"
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)
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func command(args ...string) *exec.Cmd {
9+
return &exec.Cmd{
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Path: Self(),
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Args: args,
12+
SysProcAttr: &syscall.SysProcAttr{
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Pdeathsig: syscall.SIGTERM,
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},
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}
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}

‎pkg/reexec/reexec_other.go‎

Lines changed: 14 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -0,0 +1,14 @@
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//go:build !linux
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3+
package reexec
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import (
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"os/exec"
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)
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func command(args ...string) *exec.Cmd {
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return &exec.Cmd{
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Path: Self(),
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Args: args,
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}
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}

‎pkg/reexec/reexec_test.go‎

Lines changed: 6 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -6,8 +6,10 @@ import (
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"testing"
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)
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const testReExec = "test-reexec"
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func init() {
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Register("reexec", func() {
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Register(testReExec, func() {
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panic("Return Error")
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})
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Init()
@@ -16,17 +18,17 @@ func init() {
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func TestRegister(t *testing.T) {
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defer func() {
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if r := recover(); r != nil {
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const expected = `reexec func already registered under name "reexec"`
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const expected = `reexec func already registered under name "test-reexec"`
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if r != expected {
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t.Errorf("got %q, want %q", r, expected)
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}
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}
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}()
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Register("reexec", func() {})
27+
Register(testReExec, func() {})
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}
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2830
func TestCommand(t *testing.T) {
29-
cmd := Command("reexec")
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cmd := Command(testReExec)
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w, err := cmd.StdinPipe()
3133
if err != nil {
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t.Fatalf("Error on pipe creation: %v", err)

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