From 9b0d1ffcf80ca8d7d63a441b18c2327ddc682ef6 Mon Sep 17 00:00:00 2001
From: Guillaume Lours <705411+glours@users.noreply.github.com>
Date: Fri, 16 Feb 2024 17:17:16 +0100
Subject: [PATCH] Add a fallback check of Watch pid on Windows False positives
 were detected when checking the previous watch process state

Signed-off-by: Guillaume Lours <705411+glours@users.noreply.github.com>
---
 go.mod                             |  1 +
 go.sum                             |  2 ++
 internal/locker/pidfile.go         |  7 -----
 internal/locker/pidfile_unix.go    | 29 ++++++++++++++++++
 internal/locker/pidfile_windows.go | 47 ++++++++++++++++++++++++++++++
 5 files changed, 79 insertions(+), 7 deletions(-)
 create mode 100644 internal/locker/pidfile_unix.go
 create mode 100644 internal/locker/pidfile_windows.go

diff --git a/go.mod b/go.mod
index dd28fa487..06555b35b 100644
--- a/go.mod
+++ b/go.mod
@@ -23,6 +23,7 @@ require (
 	github.com/hashicorp/go-version v1.6.0
 	github.com/jonboulle/clockwork v0.4.0
 	github.com/mattn/go-shellwords v1.0.12
+	github.com/mitchellh/go-ps v1.0.0
 	github.com/mitchellh/mapstructure v1.5.0
 	github.com/moby/buildkit v0.13.0-beta1.0.20231219135447-957cb50df991
 	github.com/moby/patternmatcher v0.6.0
diff --git a/go.sum b/go.sum
index 19dd1afd4..abfe07b7b 100644
--- a/go.sum
+++ b/go.sum
@@ -331,6 +331,8 @@ github.com/miekg/pkcs11 v1.1.1 h1:Ugu9pdy6vAYku5DEpVWVFPYnzV+bxB+iRdbuFSu7TvU=
 github.com/miekg/pkcs11 v1.1.1/go.mod h1:XsNlhZGX73bx86s2hdc/FuaLm2CPZJemRLMA+WTFxgs=
 github.com/mitchellh/copystructure v1.2.0 h1:vpKXTN4ewci03Vljg/q9QvCGUDttBOGBIa15WveJJGw=
 github.com/mitchellh/copystructure v1.2.0/go.mod h1:qLl+cE2AmVv+CoeAwDPye/v+N2HKCj9FbZEVFJRxO9s=
+github.com/mitchellh/go-ps v1.0.0 h1:i6ampVEEF4wQFF+bkYfwYgY+F/uYJDktmvLPf7qIgjc=
+github.com/mitchellh/go-ps v1.0.0/go.mod h1:J4lOc8z8yJs6vUwklHw2XEIiT4z4C40KtWVN3nvg8Pg=
 github.com/mitchellh/mapstructure v0.0.0-20150613213606-2caf8efc9366/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh9fWfEaFds41c1Y=
 github.com/mitchellh/mapstructure v1.5.0 h1:jeMsZIYE/09sWLaz43PL7Gy6RuMjD2eJVyuac5Z2hdY=
 github.com/mitchellh/mapstructure v1.5.0/go.mod h1:bFUtVrKA4DC2yAKiSyO/QUcy7e+RRV2QTWOzhPopBRo=
diff --git a/internal/locker/pidfile.go b/internal/locker/pidfile.go
index ea688fb66..08dcea1f3 100644
--- a/internal/locker/pidfile.go
+++ b/internal/locker/pidfile.go
@@ -18,10 +18,7 @@ package locker
 
 import (
 	"fmt"
-	"os"
 	"path/filepath"
-
-	"github.com/docker/docker/pkg/pidfile"
 )
 
 type Pidfile struct {
@@ -36,7 +33,3 @@ func NewPidfile(projectName string) (*Pidfile, error) {
 	path := filepath.Join(run, fmt.Sprintf("%s.pid", projectName))
 	return &Pidfile{path: path}, nil
 }
-
-func (f *Pidfile) Lock() error {
-	return pidfile.Write(f.path, os.Getpid())
-}
diff --git a/internal/locker/pidfile_unix.go b/internal/locker/pidfile_unix.go
new file mode 100644
index 000000000..484b65d82
--- /dev/null
+++ b/internal/locker/pidfile_unix.go
@@ -0,0 +1,29 @@
+//go:build !windows
+
+/*
+   Copyright 2023 Docker Compose CLI authors
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package locker
+
+import (
+	"os"
+
+	"github.com/docker/docker/pkg/pidfile"
+)
+
+func (f *Pidfile) Lock() error {
+	return pidfile.Write(f.path, os.Getpid())
+}
diff --git a/internal/locker/pidfile_windows.go b/internal/locker/pidfile_windows.go
new file mode 100644
index 000000000..9f8d4c3ee
--- /dev/null
+++ b/internal/locker/pidfile_windows.go
@@ -0,0 +1,47 @@
+//go:build windows
+
+/*
+   Copyright 2023 Docker Compose CLI authors
+
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+*/
+
+package locker
+
+import (
+	"github.com/docker/docker/pkg/pidfile"
+	"github.com/mitchellh/go-ps"
+	"os"
+)
+
+func (f *Pidfile) Lock() error {
+	newPID := os.Getpid()
+	err := pidfile.Write(f.path, newPID)
+	if err != nil {
+		// Get PID registered in the file
+		pid, errPid := pidfile.Read(f.path)
+		if errPid != nil {
+			return err
+		}
+		// Some users faced issues on Windows where the process written in the pidfile was identified as still existing
+		// So we used a 2nd process library to verify if this not a false positive feedback
+		// Check if the process exists
+		process, errPid := ps.FindProcess(pid)
+		if process == nil && errPid == nil {
+			// If the process does not exist, remove the pidfile and try to lock again
+			_ = os.Remove(f.path)
+			return pidfile.Write(f.path, newPID)
+		}
+	}
+	return err
+}