initial commit

scripts/debug-coredump.ts

@@ -0,0 +1,67 @@
+import fs from "node:fs";
+import { tmpdir } from "node:os";
+import { basename, join } from "node:path";
+import { parseArgs } from "node:util";
+
+// usage: bun debug-coredump.ts
+// -p <PID of the test that crashed> (buildkite should show this)
+// -b <URL to the bun-profile.zip artifact for the appropriate platform>
+// -c <URL to the bun-cores.tar.gz.age artifact for the appropriate platform>
+// -d <debugger> (default: lldb)
+const {
+  values: { pid: stringPid, ["build-url"]: buildUrl, ["cores-url"]: coresUrl, debugger: debuggerPath },
+} = parseArgs({
+  options: {
+    pid: { type: "string", short: "p" },
+    ["build-url"]: { type: "string", short: "b" },
+    ["cores-url"]: { type: "string", short: "c" },
+    debugger: { type: "string", short: "d", default: "lldb" },
+  },
+});
+
+if (stringPid === undefined) throw new Error("no PID given");
+const pid = parseInt(stringPid);
+if (buildUrl === undefined) throw new Error("no build-url given");
+if (coresUrl === undefined) throw new Error("no cores-url given");
+if (!process.env.AGE_CORES_IDENTITY?.startsWith("AGE-SECRET-KEY-"))
+  throw new Error("no identity given in $AGE_CORES_IDENTITY");
+
+const id = Bun.hash(buildUrl + coresUrl).toString(36);
+const dir = join(tmpdir(), `debug-coredump-${id}.tmp`);
+fs.mkdirSync(dir, { recursive: true });
+
+if (!fs.existsSync(join(dir, "bun-profile")) || !fs.existsSync(join(dir, `bun-${pid}.core`))) {
+  console.log("downloading bun-profile.zip");
+  const zip = await (await fetch(buildUrl)).arrayBuffer();
+  await Bun.write(join(dir, "bun-profile.zip"), zip);
+  // -j: junk paths (don't create directories when extracting)
+  // -o: overwrite without prompting
+  // -d: extract to this directory instead of cwd
+  await Bun.$`unzip -j -o ${join(dir, "bun-profile.zip")} -d ${dir}`;
+
+  console.log("downloading cores");
+  const cores = await (await fetch(coresUrl)).arrayBuffer();
+  await Bun.$`bash -c ${`age -d -i <(echo "$AGE_CORES_IDENTITY")`} < ${cores} | tar -zxvC ${dir}`;
+
+  console.log("moving cores out of nested directory");
+  for await (const file of new Bun.Glob("bun-cores-*/*.core").scan(dir)) {
+    fs.renameSync(join(dir, file), join(dir, basename(file)));
+  }
+} else {
+  console.log(`already downloaded in ${dir}`);
+}
+
+const desiredCore = join(dir, (await new Bun.Glob(`*${pid}.core`).scan(dir).next()).value);
+
+const args = [debuggerPath, "--core", desiredCore, join(dir, "bun-profile")];
+
+console.log("launching debugger:");
+console.log(args.map(Bun.$.escape).join(" "));
+
+const proc = Bun.spawn(args, {
+  stdin: "inherit",
+  stdout: "inherit",
+  stderr: "inherit",
+});
+await proc.exited;
+process.exit(proc.exitCode);