void HeapProfileRequestHandler::handleRequest(Transport *transport) {
const char *url = transport->getCommand().c_str();
if (!strcmp(url, "hhprof/start")) {
// if we can place the request, send a 200
if (handleStartRequest(transport)) {
transport->sendString("OK\n", 200);
} else {
transport->sendString("Resource Unavailable\n", 503);
}
} else if (!strcmp(url, "pprof/cmdline")) {
// the first thing pprof does when you call the script is find out
// the name of the binary running on the remote server
transport->sendString(current_executable_path(), 200);
} else if (!strcmp(url, "pprof/heap")) {
// the next thing pprof does is hit this endpoint and get a profile
// dump
ProfileController::waitForProfile([&](const ProfileDump& dump) {
transport->sendString(dump.toPProfFormat(), 200);
});
} else if (!strcmp(url, "pprof/symbol")) {
// lastly, pprof hits this endpoint three times. the first time, it
// hits with a HEAD request, which gives it some knowledge as to the
// presence of the endpoint. then it hits with a GET request, and
// expects the number of defined symbols in response. finally, it
// hits with a POST request, with the POST data being a plus-separated
// list of addresses for which it wants symbols
if (transport->getMethod() == Transport::Method::HEAD) {
transport->sendString("OK\n", 200);
} else if (transport->getMethod() == Transport::Method::GET) {
// actual number of sumbols is not really relevant
// from the pprof documentation, pprof only considers values
// that are either zero or non-zero
transport->sendString("num_symbols: 1\n", 200);
} else if (transport->getMethod() == Transport::Method::POST) {
// split the post data by '+' character and resolve the symbol
// for each
int size;
auto data = static_cast<const char *>(transport->getPostData(size));
std::string res;
std::vector<folly::StringPiece> addrs;
folly::split('+', folly::StringPiece(data, size), addrs);
for (const auto &addr : addrs) {
// for each address we get from pprof, it expects a line formatted
// like the following
// <address>\t<symbol name>
if (!addr.size()) {
continue;
}
std::string val(addr.data(), addr.size());
SrcKey sk = SrcKey::fromAtomicInt(
static_cast<uint64_t>(std::stoll(val, 0, 16))
);
folly::toAppend(addr, "\t", sk.getSymbol(), "\n", &res);
}
transport->sendString(res, 200);
if (RuntimeOption::ClientExecutionMode() &&
RuntimeOption::HHProfServerProfileClientMode) {
std::unique_lock<std::mutex> lock(s_clientMutex);
s_cond = true;
s_clientWaitq.notify_all();
}
}
} else if (!strcmp(url, "hhprof/stop")) {
// user has requested cancellation of the current profile dump
ProfileController::cancelRequest();
transport->sendString("OK\n", 200);
} else {
// the pprof server doesn't understand any other endpoints so just error
// out
Logger::Warning(folly::format(
"Unknown HHProf endpoint requested, command was: {}", url
).str());
transport->sendString("Not Found\n", 404);
}
}
