feature: using setsid to support terminating clone/fetch/pull/push on Linux gracefully

Signed-off-by: leo <longshuang@msn.cn>

Author: love-linger

src/Commands/Command.cs

@@ -158,8 +158,36 @@ protected async Task<Result> ReadToEndAsync()
 
         protected ProcessStartInfo CreateGitStartInfo(bool redirect)
         {
+            var useSetSid = OperatingSystem.IsLinux() && CancellationToken.CanBeCanceled;
+            var selfExecFile = Environment.ProcessPath;
+            var builder = new StringBuilder(2048);
+
+            if (useSetSid)
+                builder.Append(Native.OS.GitExecutable.Quoted()).Append(' ');
+
+            builder
+                .Append("--no-pager -c core.quotepath=off -c credential.helper=")
+                .Append(Native.OS.CredentialHelper)
+                .Append(' ');
+
+            switch (Editor)
+            {
+                case EditorType.CoreEditor:
+                    builder.Append($"""-c core.editor="\"{selfExecFile}\" --core-editor" """);
+                    break;
+                case EditorType.RebaseEditor:
+                    builder.Append($"""-c core.editor="\"{selfExecFile}\" --rebase-message-editor" -c sequence.editor="\"{selfExecFile}\" --rebase-todo-editor" -c rebase.abbreviateCommands=true """);
+                    break;
+                default:
+                    builder.Append("-c core.editor=true ");
+                    break;
+            }
+
+            builder.Append(Args);
+
             var start = new ProcessStartInfo();
-            start.FileName = Native.OS.GitExecutable;
+            start.FileName = useSetSid ? "setsid" : Native.OS.GitExecutable;
+            start.Arguments = builder.ToString();
             start.UseShellExecute = false;
             start.CreateNoWindow = true;
 
@@ -172,7 +200,6 @@ protected ProcessStartInfo CreateGitStartInfo(bool redirect)
             }
 
             // Force using this app as SSH askpass program
-            var selfExecFile = Environment.ProcessPath;
             start.Environment.Add("SSH_ASKPASS", selfExecFile); // Can not use parameter here, because it invoked by SSH with `exec`
             start.Environment.Add("SSH_ASKPASS_REQUIRE", "prefer");
             start.Environment.Add("SOURCEGIT_LAUNCH_AS_ASKPASS", "TRUE");
@@ -190,28 +217,6 @@ protected ProcessStartInfo CreateGitStartInfo(bool redirect)
                 start.Environment.Add("LC_ALL", "C");
             }
 
-            var builder = new StringBuilder(2048);
-            builder
-                .Append("--no-pager -c core.quotepath=off -c credential.helper=")
-                .Append(Native.OS.CredentialHelper)
-                .Append(' ');
-
-            switch (Editor)
-            {
-                case EditorType.CoreEditor:
-                    builder.Append($"""-c core.editor="\"{selfExecFile}\" --core-editor" """);
-                    break;
-                case EditorType.RebaseEditor:
-                    builder.Append($"""-c core.editor="\"{selfExecFile}\" --rebase-message-editor" -c sequence.editor="\"{selfExecFile}\" --rebase-todo-editor" -c rebase.abbreviateCommands=true """);
-                    break;
-                default:
-                    builder.Append("-c core.editor=true ");
-                    break;
-            }
-
-            builder.Append(Args);
-            start.Arguments = builder.ToString();
-
             // Working directory
             if (!string.IsNullOrEmpty(WorkingDirectory))
                 start.WorkingDirectory = WorkingDirectory;

src/Native/Linux.cs

@@ -2,6 +2,7 @@
 using System.Collections.Generic;
 using System.Diagnostics;
 using System.IO;
+using System.Runtime.InteropServices;
 using System.Runtime.Versioning;
 
 using Avalonia;
@@ -13,6 +14,9 @@ namespace SourceGit.Native
     [SupportedOSPlatform("linux")]
     internal class Linux : OS.IBackend
     {
+        [DllImport("libc", SetLastError = true)]
+        private static extern int kill(int pid, int sig);
+
         public void SetupApp(AppBuilder builder)
         {
             builder.With(new X11PlatformOptions() { EnableIme = true });
@@ -140,7 +144,8 @@ public void OpenWithDefaultEditor(string file)
 
         public void TerminateProcess(Process proc)
         {
-            proc.Kill(true);
+            if (kill(-proc.Id, 15) != 0)
+                proc.Kill(true); // Fallback to force kill if the process is not terminated by SIGTERM
         }
 
         private string FindExecutable(string filename)

src/ViewModels/Clone.cs

@@ -120,7 +120,7 @@ public override async Task<bool> Sure()
                 .WithCancellation(token)
                 .Use(log)
                 .ExecAsync();
-            if (!succ)
+            if (!succ || token.IsCancellationRequested)
                 return false;
 
             var path = _parentFolder;

src/ViewModels/CommitDetail.cs

@@ -514,7 +514,6 @@ private void Refresh()
             Task.Run(async () =>
             {
                 var changes = await new Commands.CompareRevisions(_repo.FullPath, _commit.FirstParentToCompare, _commit.SHA)
-                    .WithCancellation(token)
                     .ReadAsync()
                     .ConfigureAwait(false);
 

src/ViewModels/Popup.cs

@@ -12,8 +12,8 @@ public bool CanTerminate
             get => _canTerminate;
             protected set
             {
-                // Terminating a process is only supported on Windows.
-                if (OperatingSystem.IsWindows())
+                // Terminating a process is only supported on Windows/Linux.
+                if (!OperatingSystem.IsMacOS())
                     SetProperty(ref _canTerminate, value);
             }
         }