private void diagnoseFailedLoad(Exception cause) {
Process proc = process.getProcess();
try {
int val = proc.exitValue();
new RuntimeException("Jenkins died loading. Exit code " + val, cause);
} catch (IllegalThreadStateException _) {
// Process alive
}
// Try to get stacktrace
Class<?> clazz;
Field pidField;
try {
clazz = Class.forName("java.lang.UNIXProcess");
pidField = clazz.getDeclaredField("pid");
pidField.setAccessible(true);
} catch (Exception e) {
LinkageError x = new LinkageError();
x.initCause(e);
throw x;
}
if (clazz.isAssignableFrom(proc.getClass())) {
int pid;
try {
pid = (int) pidField.get(proc);
} catch (IllegalArgumentException | IllegalAccessException e) {
throw new AssertionError(e);
}
try {
Process jstack = new ProcessBuilder("jstack", String.valueOf(pid)).start();
if (jstack.waitFor() == 0) {
StringWriter writer = new StringWriter();
IOUtils.copy(jstack.getInputStream(), writer);
RuntimeException ex = new RuntimeException(
cause.getMessage() + "\n\n" + writer.toString()
);
ex.setStackTrace(cause.getStackTrace());
throw ex;
}
} catch (IOException | InterruptedException e) {
throw new AssertionError(e);
}
}
throw new Error(cause);
}