#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/epoll.h>
+#include <signal.h>
#include <errno.h>
+#include <ctype.h>
#include <vector>
#include <string>
#include <map>
+
#include "metacube.h"
+#include "server.h"
+#include "serverpool.h"
+#include "input.h"
+#include "state.pb.h"
-#define NUM_SERVERS 4
#define STREAM_ID "stream"
#define STREAM_URL "http://gruessi.zrh.sesse.net:4013/"
-#define BACKLOG_SIZE 1048576
-#define PORT 9094
using namespace std;
-// Locks a pthread mutex, RAII-style.
-class MutexLock {
-public:
- MutexLock(pthread_mutex_t *mutex);
- ~MutexLock();
-
-private:
- pthread_mutex_t *mutex;
-};
-
-MutexLock::MutexLock(pthread_mutex_t *mutex)
- : mutex(mutex)
-{
- pthread_mutex_lock(mutex);
-}
-
-MutexLock::~MutexLock()
-{
- pthread_mutex_unlock(mutex);
-}
-
-struct Client {
- enum State { READING_REQUEST, SENDING_HEADER, SENDING_DATA };
- State state;
-
- // The HTTP request, as sent by the client. If we are in READING_REQUEST,
- // this might not be finished.
- string client_request;
-
-#if 0
- // What stream we're connecting to; parsed from client_request.
- // Not relevant for READING_REQUEST.
- string stream_id;
-#endif
-
- // Number of bytes we've sent of the header. Only relevant for SENDING_HEADER.
- size_t header_bytes_sent;
-
- // Number of bytes we've sent of data. Only relevant for SENDING_DATA.
- size_t bytes_sent;
-};
-
-struct Stream {
- // The HTTP response header, plus the video stream header (if any).
- string header;
-
- // The stream data itself, stored in a circular buffer.
- char data[BACKLOG_SIZE];
-
- // How many bytes <data> contains. Can very well be larger than BACKLOG_SIZE,
- // since the buffer wraps.
- size_t data_size;
-};
-
-class Server {
-public:
- Server();
-
- // Start a new thread that handles clients.
- void run();
- void add_client(int sock);
- void add_stream(const string &stream_id);
- void set_header(const string &stream_id, const string &header);
- void add_data(const string &stream_id, const char *data, size_t bytes);
-
-private:
- pthread_mutex_t mutex;
-
- // Map from stream ID to stream.
- map<string, Stream> streams;
-
- // Map from file descriptor to client.
- map<int, Client> clients;
-
- int epoll_fd;
-
- // Recover the this pointer, and call do_work().
- static void *do_work_thunk(void *arg);
-
- // The actual worker thread.
- void do_work();
-};
-
-Server *servers = NULL;
-
-Server::Server()
-{
- pthread_mutex_init(&mutex, NULL);
-
- epoll_fd = epoll_create(1024); // Size argument is ignored.
- if (epoll_fd == -1) {
- perror("epoll_fd");
- exit(1);
- }
-}
-
-void Server::run()
-{
- pthread_t thread;
- pthread_create(&thread, NULL, Server::do_work_thunk, this);
-}
-
-void *Server::do_work_thunk(void *arg)
-{
- Server *server = static_cast<Server *>(arg);
- server->do_work();
- return NULL;
-}
-
-void Server::do_work()
-{
- for ( ;; ) {
- MutexLock lock(&mutex);
- printf("server thread running\n");
- sleep(1);
- }
-}
-
-void Server::add_client(int sock)
-{
- MutexLock lock(&mutex);
- Client new_client;
- new_client.state = Client::READING_REQUEST;
- new_client.header_bytes_sent = 0;
- new_client.bytes_sent = 0;
-
- clients.insert(make_pair(sock, new_client));
-
- // Start listening on data from this socket.
- epoll_event ev;
- ev.events = EPOLLIN;
- ev.data.fd = sock;
- if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, sock, &ev) == -1) {
- perror("epoll_ctl(EPOLL_CTL_ADD)");
- exit(1);
- }
-}
-
-void Server::add_stream(const string &stream_id)
-{
- // TODO
-}
-
-void Server::set_header(const string &stream_id, const string &header)
-{
- // TODO
- printf("got header! %lu bytes\n", header.size());
-}
-
-void Server::add_data(const string &stream_id, const char *data, size_t bytes)
-{
- // TODO
-}
-
-class Input {
-public:
- Input(const string &stream_id);
-
- // Connect to the given URL and start streaming.
- // WARNING: Currently this blocks; it does not run in a separate thread!
- void run(const string &url);
-
-private:
- // Recovers the this pointer and calls curl_callback().
- static size_t curl_callback_thunk(char *ptr, size_t size, size_t nmemb, void *userdata);
-
- // Stores the given data, looks for Metacube blocks (skipping data if needed),
- // and calls process_block() for each one.
- void curl_callback(char *ptr, size_t bytes);
- void process_block(const char *data, uint32_t size, uint32_t flags);
-
- // Drops <num_bytes> bytes from the head of <pending_data>,
- // and outputs a warning.
- void drop_pending_data(size_t num_bytes);
-
- string stream_id;
-
- // Data we have received but not fully processed yet.
- vector<char> pending_data;
-
- // If <pending_data> starts with a Metacube header,
- // this is true.
- bool has_metacube_header;
-};
-
-Input::Input(const string &stream_id)
- : stream_id(stream_id),
- has_metacube_header(false)
-{
-}
-
-void Input::run(const string &url)
-{
- CURL *curl = curl_easy_init();
- curl_easy_setopt(curl, CURLOPT_URL, STREAM_URL);
- curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, &Input::curl_callback_thunk);
- curl_easy_setopt(curl, CURLOPT_WRITEDATA, this);
- curl_easy_perform(curl);
-}
-
-size_t Input::curl_callback_thunk(char *ptr, size_t size, size_t nmemb, void *userdata)
-{
- Input *input = static_cast<Input *>(userdata);
- size_t bytes = size * nmemb;
- input->curl_callback(ptr, bytes);
- return bytes;
-}
-
-void Input::curl_callback(char *ptr, size_t bytes)
-{
- pending_data.insert(pending_data.end(), ptr, ptr + bytes);
-
- for ( ;; ) {
- // If we don't have enough data (yet) for even the Metacube header, just return.
- if (pending_data.size() < sizeof(metacube_block_header)) {
- return;
- }
-
- // Make sure we have the Metacube sync header at the start.
- // We may need to skip over junk data (it _should_ not happen, though).
- if (!has_metacube_header) {
- char *ptr = static_cast<char *>(
- memmem(pending_data.data(), pending_data.size(),
- METACUBE_SYNC, strlen(METACUBE_SYNC)));
- if (ptr == NULL) {
- // OK, so we didn't find the sync marker. We know then that
- // we do not have the _full_ marker in the buffer, but we
- // could have N-1 bytes. Drop everything before that,
- // and then give up.
- drop_pending_data(pending_data.size() - (strlen(METACUBE_SYNC) - 1));
- return;
- } else {
- // Yay, we found the header. Drop everything (if anything) before it.
- drop_pending_data(ptr - pending_data.data());
- has_metacube_header = true;
-
- // Re-check that we have the entire header; we could have dropped data.
- if (pending_data.size() < sizeof(metacube_block_header)) {
- return;
- }
- }
- }
-
- // Now it's safe to read the header.
- metacube_block_header *hdr = reinterpret_cast<metacube_block_header *>(pending_data.data());
- assert(memcmp(hdr->sync, METACUBE_SYNC, sizeof(hdr->sync)) == 0);
- uint32_t size = ntohl(hdr->size);
- uint32_t flags = ntohl(hdr->flags);
+ServerPool *servers = NULL;
+volatile bool hupped = false;
- // See if we have the entire block. If not, wait for more data.
- if (pending_data.size() < sizeof(metacube_block_header) + size) {
- return;
- }
-
- process_block(pending_data.data(), size, flags);
-
- // Consume this block. This isn't the most efficient way of dealing with things
- // should we have many blocks, but these routines don't need to be too efficient
- // anyway.
- pending_data.erase(pending_data.begin(), pending_data.begin() + sizeof(metacube_block_header) + size);
- }
-}
-
-void Input::process_block(const char *data, uint32_t size, uint32_t flags)
-{
- if (flags & METACUBE_FLAGS_HEADER) {
- string header(data, data + size);
- for (int i = 0; i < NUM_SERVERS; ++i) {
- servers[i].set_header(stream_id, header);
- }
- } else {
- for (int i = 0; i < NUM_SERVERS; ++i) {
- servers[i].add_data(stream_id, data, size);
- }
- }
-}
-
-void Input::drop_pending_data(size_t num_bytes)
+void hup(int ignored)
{
- if (num_bytes == 0) {
- return;
- }
- fprintf(stderr, "Warning: Dropping %lld junk bytes from stream, maybe it is not a Metacube stream?\n",
- (long long)num_bytes);
- pending_data.erase(pending_data.begin(), pending_data.begin() + num_bytes);
+ hupped = true;
}
int create_server_socket(int port)
exit(1);
}
+ int one = 1;
+ if (setsockopt(server_sock, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)) == -1) {
+ perror("setsockopt(SO_REUSEADDR)");
+ exit(1);
+ }
+
// We want dual-stack sockets. (Sorry, OpenBSD and Windows XP...)
int zero = 0;
if (setsockopt(server_sock, IPPROTO_IPV6, IPV6_V6ONLY, &zero, sizeof(zero)) == -1) {
}
// Pick a server, round-robin, and hand over the socket to it.
- servers[num_accepted % NUM_SERVERS].add_client(sock);
+ servers->add_client(sock);
++num_accepted;
}
}
+// Serialize the given state to a file descriptor, and return the (still open)
+// descriptor.
+int make_tempfile(const CubemapStateProto &state)
+{
+ char tmpl[] = "/tmp/cubemapstate.XXXXXX";
+ int state_fd = mkstemp(tmpl);
+ if (state_fd == -1) {
+ perror("mkstemp");
+ exit(1);
+ }
+
+ string serialized;
+ state.SerializeToString(&serialized);
+
+ const char *ptr = serialized.data();
+ size_t to_write = serialized.size();
+ while (to_write > 0) {
+ ssize_t ret = write(state_fd, ptr, to_write);
+ if (ret == -1) {
+ perror("write");
+ exit(1);
+ }
+
+ ptr += ret;
+ to_write -= ret;
+ }
+
+ return state_fd;
+}
+
+// Read the state back from the file descriptor made by make_tempfile,
+// and close it.
+CubemapStateProto read_tempfile(int state_fd)
+{
+ if (lseek(state_fd, 0, SEEK_SET) == -1) {
+ perror("lseek");
+ exit(1);
+ }
+
+ string serialized;
+ char buf[4096];
+ for ( ;; ) {
+ ssize_t ret = read(state_fd, buf, sizeof(buf));
+ if (ret == -1) {
+ perror("read");
+ exit(1);
+ }
+ if (ret == 0) {
+ // EOF.
+ break;
+ }
+
+ serialized.append(string(buf, buf + ret));
+ }
+
+ close(state_fd); // Implicitly deletes the file.
+
+ CubemapStateProto state;
+ if (!state.ParseFromString(serialized)) {
+ fprintf(stderr, "PANIC: Failed deserialization of state.\n");
+ exit(1);
+ }
+
+ return state;
+}
+
+// Split a line on whitespace, e.g. "foo bar baz" -> {"foo", "bar", "baz"}.
+vector<string> split_tokens(const string &line)
+{
+ vector<string> ret;
+ string current_token;
+
+ for (size_t i = 0; i < line.size(); ++i) {
+ if (isspace(line[i])) {
+ if (!current_token.empty()) {
+ ret.push_back(current_token);
+ }
+ current_token.clear();
+ } else {
+ current_token.push_back(line[i]);
+ }
+ }
+ if (!current_token.empty()) {
+ ret.push_back(current_token);
+ }
+ return ret;
+}
+
+struct ConfigLine {
+ string keyword;
+ vector<string> arguments;
+ map<string, string> parameters;
+};
+
+// Parse the configuration file.
+vector<ConfigLine> parse_config(const string &filename)
+{
+ vector<ConfigLine> ret;
+
+ FILE *fp = fopen(filename.c_str(), "r");
+ if (fp == NULL) {
+ perror(filename.c_str());
+ exit(1);
+ }
+
+ char buf[4096];
+ while (!feof(fp)) {
+ if (fgets(buf, sizeof(buf), fp) == NULL) {
+ break;
+ }
+
+ // Chop off the string at the first #, \r or \n.
+ buf[strcspn(buf, "#\r\n")] = 0;
+
+ // Remove all whitespace from the end of the string.
+ size_t len = strlen(buf);
+ while (len > 0 && isspace(buf[len - 1])) {
+ buf[--len] = 0;
+ }
+
+ // If the line is now all blank, ignore it.
+ if (len == 0) {
+ continue;
+ }
+
+ vector<string> tokens = split_tokens(buf);
+ assert(!tokens.empty());
+
+ ConfigLine line;
+ line.keyword = tokens[0];
+
+ for (size_t i = 1; i < tokens.size(); ++i) {
+ // foo=bar is a parameter; anything else is an argument.
+ size_t equals_pos = tokens[i].find_first_of('=');
+ if (equals_pos == string::npos) {
+ line.arguments.push_back(tokens[i]);
+ } else {
+ string key = tokens[i].substr(0, equals_pos);
+ string value = tokens[i].substr(equals_pos + 1, string::npos);
+ line.parameters.insert(make_pair(key, value));
+ }
+ }
+
+ ret.push_back(line);
+ }
+
+ fclose(fp);
+ return ret;
+}
+
+// Note: Limits are inclusive.
+int fetch_config_int(const vector<ConfigLine> &config, const string &keyword, int min_limit, int max_limit)
+{
+ bool value_found = false;
+ int value = -1;
+ for (unsigned i = 0; i < config.size(); ++i) {
+ if (config[i].keyword != keyword) {
+ continue;
+ }
+ if (config[i].parameters.size() > 0 ||
+ config[i].arguments.size() != 1) {
+ fprintf(stderr, "ERROR: '%s' takes one argument and no parameters\n", keyword.c_str());
+ exit(1);
+ }
+ value_found = true;
+ value = atoi(config[i].arguments[0].c_str()); // TODO: verify int validity.
+ }
+ if (!value_found) {
+ fprintf(stderr, "ERROR: Missing '%s' statement in config file.\n",
+ keyword.c_str());
+ exit(1);
+ }
+ if (value < min_limit || value > max_limit) {
+ fprintf(stderr, "ERROR: '%s' is set to %d, must be in [%d,%d]\n",
+ keyword.c_str(), value, min_limit, max_limit);
+ exit(1);
+ }
+ return value;
+}
+
int main(int argc, char **argv)
{
- servers = new Server[NUM_SERVERS];
- for (int i = 0; i < NUM_SERVERS; ++i) {
- servers[i].add_stream(STREAM_ID);
- servers[i].run();
+ fprintf(stderr, "\nCubemap starting.\n");
+
+ string config_filename = (argc == 1) ? "cubemap.config" : argv[1];
+ vector<ConfigLine> config = parse_config(config_filename);
+
+ int port = fetch_config_int(config, "port", 1, 65535);
+ int num_servers = fetch_config_int(config, "num_servers", 1, 20000); // Insanely high max limit.
+
+ servers = new ServerPool(num_servers);
+
+ int server_sock = -1, old_port = -1;
+ if (argc == 4 && strcmp(argv[2], "-state") == 0) {
+ fprintf(stderr, "Deserializing state from previous process... ");
+ int state_fd = atoi(argv[3]);
+ CubemapStateProto loaded_state = read_tempfile(state_fd);
+
+ // Deserialize the streams.
+ for (int i = 0; i < loaded_state.streams_size(); ++i) {
+ servers->add_stream_from_serialized(loaded_state.streams(i));
+ }
+
+ // Put back the existing clients. It doesn't matter which server we
+ // allocate them to, so just do round-robin.
+ for (int i = 0; i < loaded_state.clients_size(); ++i) {
+ servers->add_client_from_serialized(loaded_state.clients(i));
+ }
+
+ // Deserialize the server socket.
+ server_sock = loaded_state.server_sock();
+ old_port = loaded_state.port();
+
+ fprintf(stderr, "done.\n");
+ } else{
+ // TODO: This should come from the config file.
+ servers->add_stream(STREAM_ID);
+ }
+
+ // Open a new server socket if we do not already have one, or if we changed ports.
+ if (server_sock != -1 && port != old_port) {
+ fprintf(stderr, "NOTE: Port changed from %d to %d; opening new socket.\n", old_port, port);
+ close(server_sock);
+ server_sock = -1;
+ }
+ if (server_sock == -1) {
+ server_sock = create_server_socket(port);
}
- int server_sock = create_server_socket(PORT);
+ servers->run();
pthread_t acceptor_thread;
pthread_create(&acceptor_thread, NULL, acceptor_thread_run, reinterpret_cast<void *>(server_sock));
- Input input(STREAM_ID);
- input.run(STREAM_URL);
+ // TODO: This should come from the config file.
+ Input input(STREAM_ID, STREAM_URL);
+ input.run();
+
+ signal(SIGHUP, hup);
+
+ while (!hupped) {
+ usleep(100000);
+ }
+
+ input.stop();
+
+ CubemapStateProto state;
+ state.set_server_sock(server_sock);
+ state.set_port(port);
+ for (int i = 0; i < num_servers; ++i) {
+ servers->get_server(i)->stop();
+
+ CubemapStateProto local_state = servers->get_server(i)->serialize();
+
+ // The stream state should be identical between the servers, so we only store it once.
+ if (i == 0) {
+ state.mutable_streams()->MergeFrom(local_state.streams());
+ }
+ for (int j = 0; j < local_state.clients_size(); ++j) {
+ state.add_clients()->MergeFrom(local_state.clients(j));
+ }
+ }
+ delete servers;
+
+ fprintf(stderr, "Serializing state and re-execing...\n");
+ int state_fd = make_tempfile(state);
+
+ char buf[16];
+ sprintf(buf, "%d", state_fd);
+
+ for ( ;; ) {
+ execlp(argv[0], argv[0], config_filename.c_str(), "-state", buf, NULL);
+ perror("execlp");
+ fprintf(stderr, "PANIC: re-exec of %s failed. Waiting 0.2 seconds and trying again...\n", argv[0]);
+ usleep(200000);
+ }
}
projects / cubemap / blobdiff