X-Git-Url: https://git.sesse.net/?p=cubemap;a=blobdiff_plain;f=cubemap.cpp;h=ed615a876574a8334757bd226529f58814e3ef70;hp=9f5e42e6a23b0f5cff0c37b3fecaded17b13b522;hb=6861e5c337ba300c61d8b64a3837bb43458caa3f;hpb=418ca367be670db5377ca99462906eb9c73d296b diff --git a/cubemap.cpp b/cubemap.cpp index 9f5e42e..ed615a8 100644 --- a/cubemap.cpp +++ b/cubemap.cpp @@ -7,221 +7,32 @@ #include #include #include +#include +#include +#include #include #include #include #include + #include "metacube.h" +#include "server.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 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_socket(int server_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 streams; - - // Recover the this pointer, and call do_work(). - static void *do_work_thunk(void *arg); - - // The actual worker thread. - void do_work(); -}; - -Server::Server() -{ - pthread_mutex_init(&mutex, NULL); -} - -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(arg); - server->do_work(); - return NULL; -} - -void Server::do_work() -{ - for ( ;; ) { - printf("server thread running\n"); - sleep(1); - } -} - -class Input { -public: - Input(); - void curl_callback(char *ptr, size_t bytes); - -private: - void process_block(const char *data, uint32_t size, uint32_t flags); - void drop_pending_data(size_t num_bytes); - - // Data we have received but not fully processed yet. - vector pending_data; - - // If starts with a Metacube header, - // this is true. - bool has_metacube_header; -}; - -Input::Input() - : has_metacube_header(false) -{ -} - -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( - 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(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); - - // 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) -{ - // TODO: treat it right here - printf("Block: %d bytes, flags=0x%x\n", size, flags); -} - -void Input::drop_pending_data(size_t num_bytes) -{ - 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); -} +Server *servers = NULL; +volatile bool hupped = false; -size_t curl_callback(char *ptr, size_t size, size_t nmemb, void *userdata) +void hup(int ignored) { - Input *input = static_cast(userdata); - size_t bytes = size * nmemb; - input->curl_callback(ptr, bytes); - return bytes; + hupped = true; } int create_server_socket(int port) @@ -232,6 +43,12 @@ 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) { @@ -260,10 +77,12 @@ 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); + // Get a new socket. int sock = accept(server_sock, reinterpret_cast(&addr), &addrlen); if (sock == -1 && errno == EINTR) { continue; @@ -273,28 +92,167 @@ void *acceptor_thread_run(void *arg) exit(1); } - printf("got a socket yaaaay\n"); + // Set the socket as nonblocking. + int one = 1; + if (ioctl(sock, FIONBIO, &one) == -1) { + perror("FIONBIO"); + exit(1); + } + + // Pick a server, round-robin, and hand over the socket to it. + servers[num_accepted % NUM_SERVERS].add_client(sock); + ++num_accepted; } } -Server *servers = NULL; +// 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) { + fprintf(stderr, "\nCubemap starting.\n"); + servers = new Server[NUM_SERVERS]; + + int server_sock; + if (argc == 3 && strcmp(argv[1], "-state") == 0) { + fprintf(stderr, "Deserializing state from previous process... "); + int state_fd = atoi(argv[2]); + CubemapStateProto loaded_state = read_tempfile(state_fd); + + // Deserialize the streams. + for (int i = 0; i < loaded_state.streams_size(); ++i) { + for (int j = 0; j < NUM_SERVERS; ++j) { + servers[j].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[i % NUM_SERVERS].add_client_from_serialized(loaded_state.clients(i)); + } + + // Deserialize the server socket. + server_sock = loaded_state.server_sock(); + + fprintf(stderr, "done.\n"); + } else { + // TODO: This should come from a config file. + server_sock = create_server_socket(PORT); + for (int i = 0; i < NUM_SERVERS; ++i) { + servers[i].add_stream(STREAM_ID); + } + } + for (int i = 0; i < NUM_SERVERS; ++i) { servers[i].run(); } - int server_sock = create_server_socket(PORT); - pthread_t acceptor_thread; pthread_create(&acceptor_thread, NULL, acceptor_thread_run, reinterpret_cast(server_sock)); - Input input; - CURL *curl = curl_easy_init(); - curl_easy_setopt(curl, CURLOPT_URL, STREAM_URL); - curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, curl_callback); - curl_easy_setopt(curl, CURLOPT_WRITEDATA, &input); - curl_easy_perform(curl); + 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); + for (int i = 0; i < NUM_SERVERS; ++i) { + servers[i].stop(); + + CubemapStateProto local_state = servers[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], "-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); + } }