Remove some leftover code.
[cubemap] / cubemap.cpp
index 4ee5d6f3c4d6a95fcc5dfc556a437b5cf2077a76..9b98ebab999fe6e0818528305df992c92b378f7e 100644 (file)
@@ -9,23 +9,33 @@
 #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 <set>
 
 #include "metacube.h"
+#include "parse.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 PORT 9094
 
 using namespace std;
 
-Server *servers = NULL;
+ServerPool *servers = NULL;
+volatile bool hupped = false;
+
+void hup(int ignored)
+{
+       hupped = true;
+}
 
 int create_server_socket(int port)
 {
@@ -35,7 +45,7 @@ int create_server_socket(int port)
                exit(1);
        }
 
-       int one;        
+       int one = 1;
        if (setsockopt(server_sock, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)) == -1) {
                perror("setsockopt(SO_REUSEADDR)");
                exit(1);
@@ -69,7 +79,6 @@ int create_server_socket(int port)
 void *acceptor_thread_run(void *arg)
 {
        int server_sock = int(intptr_t(arg));
-       int num_accepted = 0;
        for ( ;; ) {
                sockaddr_in6 addr;
                socklen_t addrlen = sizeof(addr);
@@ -92,24 +101,217 @@ void *acceptor_thread_run(void *arg)
                }
 
                // Pick a server, round-robin, and hand over the socket to it.
-               servers[num_accepted % NUM_SERVERS].add_client(sock);
-               ++num_accepted; 
+               servers->add_client(sock);
+       }
+}
+
+// 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;
 }
 
 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;
+       set<string> deserialized_stream_ids;
+       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));
+                       deserialized_stream_ids.insert(loaded_state.streams(i).stream_id());
+               }
+
+               // 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");
+       }
+
+       // Find all streams in the configuration file, and create them.
+       set<string> expecting_stream_ids = deserialized_stream_ids;
+       for (unsigned i = 0; i < config.size(); ++i) {
+               if (config[i].keyword != "stream") {
+                       continue;
+               }
+               if (config[i].arguments.size() != 1) {
+                       fprintf(stderr, "ERROR: 'stream' takes exactly one argument\n");
+                       exit(1);
+               }
+               string stream_id = config[i].arguments[0];
+               if (deserialized_stream_ids.count(stream_id) == 0) {
+                       servers->add_stream(stream_id);
+               }
+               expecting_stream_ids.erase(stream_id);
        }
 
-       int server_sock = create_server_socket(PORT);
+       // Warn about any servers we've lost.
+       // TODO: Make an option (delete=yes?) to actually shut down streams.
+       for (set<string>::const_iterator stream_it = expecting_stream_ids.begin();
+            stream_it != expecting_stream_ids.end();
+            ++stream_it) {
+               fprintf(stderr, "WARNING: stream '%s' disappeared from the configuration file.\n",
+                       stream_it->c_str());
+               fprintf(stderr, "         It will not be deleted, but clients will not get any new inputs.\n");
+       }
+
+       // 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);
+       }
+
+       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);
+       // Find all streams in the configuration file, and create inputs for them.
+       vector<Input *> inputs;
+       for (unsigned i = 0; i < config.size(); ++i) {
+               if (config[i].keyword != "stream") {
+                       continue;
+               }
+               assert(config[i].arguments.size() == 1);
+               string stream_id = config[i].arguments[0];
+
+               if (config[i].parameters.count("src") == 0) {
+                       fprintf(stderr, "WARNING: stream '%s' has no src= attribute, clients will not get any data.\n",
+                               stream_id.c_str());
+                       continue;
+               }
+
+               string src = config[i].parameters["src"];
+               Input *input = new Input(stream_id, src);
+               input->run();
+               inputs.push_back(input);
+       }
+
+       signal(SIGHUP, hup);
+
+       while (!hupped) {
+               usleep(100000);
+       }
+
+       // OK, we've been HUPed. Time to shut down everything, serialize, and re-exec.
+       for (size_t i = 0; i < inputs.size(); ++i) {
+               inputs[i]->stop();
+               delete inputs[i];  // TODO: serialize instead of using libcurl.
+       }
+
+       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);
+       }
 }