From 370c252b6b209bf91ca76e6d69f34a8fbb0e6cf5 Mon Sep 17 00:00:00 2001
From: Andrew Martinez <andrew.p.martinez@gmail.com>
Date: Tue, 17 Oct 2023 14:27:07 -0400
Subject: [PATCH] allows windows machines to use `agent controller init`

gops in Windows stores socket files in %TEMP% which is user specific
(e.g.C:\Users\user1\AppData\Local\Temp\gops-agent.19372.sock). For
windows instead of relying on sig(0) for a ping we assume writability.
---
 client.go       | 21 ++++++++++++++++++---
 proc_nowin.go   | 30 ++++++++++++++++++++++++++++++
 proc_windows.go | 25 +++++++++++++++++++++++++
 3 files changed, 73 insertions(+), 3 deletions(-)
 create mode 100644 proc_nowin.go
 create mode 100644 proc_windows.go

diff --git a/client.go b/client.go
index 251416c..4ab88da 100644
--- a/client.go
+++ b/client.go
@@ -1,3 +1,19 @@
+/*
+	Copyright NetFoundry Inc.
+
+	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
+
+	https://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 agent
 
 import (
@@ -14,7 +30,6 @@ import (
 	"regexp"
 	"strconv"
 	"strings"
-	"syscall"
 	"time"
 )
 
@@ -52,7 +67,7 @@ func GetGopsProcesses() ([]*Process, error) {
 			}
 			// process is alive and is reachable by us
 			if process, err := os.FindProcess(pid); err == nil {
-				if err = process.Signal(syscall.Signal(0)); err == nil {
+				if isReachable(process) {
 					proc, err := ps.FindProcess(pid)
 					if err != nil {
 						return nil, err
@@ -84,7 +99,7 @@ func tooManyProcsError(procs []*Process) error {
 		list = append(list, v.String())
 	}
 	builder := &strings.Builder{}
-	builder.WriteString("too many gops-agent process found, including [")
+	builder.WriteString("too many gops-agent process found, specify one, found [")
 	builder.WriteString(strings.Join(list, ", "))
 	builder.WriteString("]")
 	return errors.New(builder.String())
diff --git a/proc_nowin.go b/proc_nowin.go
new file mode 100644
index 0000000..e561cf4
--- /dev/null
+++ b/proc_nowin.go
@@ -0,0 +1,30 @@
+//go:build !windows
+
+/*
+	Copyright NetFoundry Inc.
+
+	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
+
+	https://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 agent
+
+import (
+	"os"
+	"syscall"
+)
+
+func isReachable(proc *os.Process) bool {
+	err := proc.Signal(syscall.Signal(0))
+
+	return err == nil
+}
diff --git a/proc_windows.go b/proc_windows.go
new file mode 100644
index 0000000..705e802
--- /dev/null
+++ b/proc_windows.go
@@ -0,0 +1,25 @@
+/*
+	Copyright NetFoundry Inc.
+
+	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
+
+	https://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 agent
+
+import (
+	"os"
+)
+
+func isReachable(proc *os.Process) bool {
+	return true
+}