[lldb-dap] Add process picker command to VS Code extension

lldb/tools/lldb-dap/src-ts/debug-configuration-provider.ts

@@ -34,6 +34,23 @@ function convertToInteger(value: any): number | undefined {
 export class LLDBDapConfigurationProvider
   implements vscode.DebugConfigurationProvider
 {
+  resolveDebugConfiguration(
+    _folder: vscode.WorkspaceFolder | undefined,
+    debugConfiguration: vscode.DebugConfiguration,
+    _token?: vscode.CancellationToken,
+  ): vscode.ProviderResult<vscode.DebugConfiguration> {
+    // Default "pid" to ${command:pickProcess} if neither "pid" nor "program" are specified
+    // in an "attach" request.
+    if (
+      debugConfiguration.request === "attach" &&
+      !("pid" in debugConfiguration) &&
+      !("program" in debugConfiguration)
+    ) {
+      debugConfiguration.pid = "${command:pickProcess}";
+    }
+    return debugConfiguration;
+  }
+
   resolveDebugConfigurationWithSubstitutedVariables(
     _folder: vscode.WorkspaceFolder | undefined,
     debugConfiguration: vscode.DebugConfiguration,

lldb/tools/lldb-dap/src-ts/process-tree/platforms/darwin-process-tree.ts

@@ -5,7 +5,7 @@ export class DarwinProcessTree extends LinuxProcessTree {
     return [
       "-axo",
       // The length of comm must be large enough or data will be truncated.
-      `pid=PID,lstart=START,comm=${"COMMAND".padEnd(256, "-")},args=ARGUMENTS`,
+      `pid=PID,state=STATE,lstart=START,comm=${"COMMAND".padEnd(256, "-")},args=ARGUMENTS`,
     ];
   }
 }

lldb/tools/lldb-dap/src-ts/process-tree/platforms/linux-process-tree.ts

@@ -9,7 +9,7 @@ export class LinuxProcessTree extends BaseProcessTree {
     return [
       "-axo",
       // The length of exe must be large enough or data will be truncated.
-      `pid=PID,lstart=START,exe:128=COMMAND,args=ARGUMENTS`,
+      `pid=PID,state=STATE,lstart=START,exe:128=COMMAND,args=ARGUMENTS`,
     ];
   }
 
@@ -23,21 +23,30 @@ export class LinuxProcessTree extends BaseProcessTree {
         return;
       }
 
-      const pid = /^\s*([0-9]+)\s*/.exec(line);
-      if (!pid) {
+      const pidAndState = /^\s*([0-9]+)\s+([a-zA-Z<>+]+)\s+/.exec(line);
+      if (!pidAndState) {
         return;
       }
 
+      // Make sure the process isn't in a trace/debug or zombie state as we cannot attach to them
+      const state = pidAndState[2];
+      if (state.includes("X") || state.includes("Z")) {
+        return;
+      }
+
+      // ps will list "-" as the command if it does not know where the executable is located
       const command = line.slice(commandOffset, argumentsOffset).trim();
       if (command === "-") {
         return;
       }
 
       return {
-        id: Number(pid[1]),
+        id: Number(pidAndState[1]),
         command,
         arguments: line.slice(argumentsOffset).trim(),
-        start: Date.parse(line.slice(pid[0].length, commandOffset).trim()),
+        start: Date.parse(
+          line.slice(pidAndState[0].length, commandOffset).trim(),
+        ),
       };
     };
   }