import type { CommandExecutor } from './execution/index.ts';
export type ProcessTreeEntry = {
pid: string;
ppid: string;
name: string;
command: string;
};
export type ProcessTreeResult = {
entries: ProcessTreeEntry[];
error?: string;
};
export async function getProcessTree(
executor: CommandExecutor,
startPid = process.pid.toString(),
): Promise<ProcessTreeResult> {
const results: ProcessTreeEntry[] = [];
const seen = new Set<string>();
let currentPid = startPid;
let lastError: string | undefined;
const parseLine = (line: string): ProcessTreeEntry | null => {
const tokens = line.trim().split(/\s+/);
if (tokens.length < 3) {
return null;
}
const pid = tokens[0];
const ppid = tokens[1];
const name = tokens[2];
if (!pid || !ppid || !name) {
return null;
}
const command = tokens.slice(3).join(' ');
return { pid, ppid, name, command };
};
const fetchProcessInfo = async (pid: string): Promise<ProcessTreeEntry | null> => {
const command = ['-o', 'pid=,ppid=,comm=,args=', '-p', pid];
const attempts = [
{ bin: '/bin/ps', label: 'Get process info (ps)' },
{ bin: 'ps', label: 'Get process info (ps fallback)' },
];
for (const attempt of attempts) {
try {
const res = await executor([attempt.bin, ...command], attempt.label);
if (!res.success) {
lastError = res.error ?? `ps returned non-zero exit code for pid ${pid}`;
continue;
}
const line = res.output.trim().split('\n')[0]?.trim();
if (!line) {
lastError = `ps returned no output for pid ${pid}`;
continue;
}
const parsed = parseLine(line);
if (!parsed) {
lastError = `ps output was not parseable for pid ${pid}`;
continue;
}
return parsed;
} catch (error) {
lastError = error instanceof Error ? error.message : String(error);
}
}
return null;
};
while (currentPid && currentPid !== '0' && !seen.has(currentPid)) {
seen.add(currentPid);
const entry = await fetchProcessInfo(currentPid);
if (!entry) {
break;
}
results.push(entry);
if (entry.ppid === entry.pid || entry.ppid === '0') {
break;
}
currentPid = entry.ppid;
}
return {
entries: results,
error: results.length === 0 ? lastError : undefined,
};
}
