Support writing a stats file listing the number of clients currently connected.

[cubemap] / main.cpp

diff --git a/main.cpp b/main.cpp
index 1bcc07bd1e612573e85176749febdb204e9979f3..3bf660a9a1c06d44d6cf785f9d18cfbb9e2f6e18 100644 (file)
--- a/main.cpp
+++ b/main.cpp
@@ -11,6 +11,7 @@
 #include <signal.h>
 #include <errno.h>
 #include <ctype.h>
+#include <fcntl.h>
 #include <vector>
 #include <string>
 #include <map>
@@ -128,6 +129,68 @@ void *acceptor_thread_run(void *arg)
        return NULL;
 }
 
+struct StatsThreadParameters {
+       string stats_file;
+       int stats_interval;
+};
+               
+void *stats_thread_run(void *arg)
+{
+       const StatsThreadParameters *parms = reinterpret_cast<StatsThreadParameters *>(arg);
+       while (!hupped) {
+               int fd;
+               FILE *fp;
+               time_t now;
+               vector<ClientStats> client_stats;
+
+               // Open a new, temporary file.
+               char *filename = strdup((parms->stats_file + ".new.XXXXXX").c_str());
+               fd = mkostemp(filename, O_WRONLY);
+               if (fd == -1) {
+                       perror(filename);
+                       free(filename);
+                       goto sleep;
+               }
+
+               fp = fdopen(fd, "w");
+               if (fp == NULL) {
+                       perror("fdopen");
+                       close(fd);
+                       unlink(filename);
+                       free(filename);
+                       goto sleep;
+               }
+
+               now = time(NULL);
+               client_stats = servers->get_client_stats();
+               for (size_t i = 0; i < client_stats.size(); ++i) {
+                       fprintf(fp, "%s %s %d %llu\n",
+                               client_stats[i].remote_addr.c_str(),
+                               client_stats[i].stream_id.c_str(),
+                               int(now - client_stats[i].connect_time),
+                               (long long unsigned)(client_stats[i].bytes_sent));
+               }
+               if (fclose(fp) == EOF) {
+                       perror("fclose");
+                       unlink(filename);
+                       free(filename);
+                       goto sleep;
+               }
+               
+               if (rename(filename, parms->stats_file.c_str()) == -1) {
+                       perror("rename");
+                       unlink(filename);
+               }
+
+sleep:
+               int left_to_sleep = parms->stats_interval;
+               do {
+                       left_to_sleep = sleep(left_to_sleep);
+               } while (left_to_sleep > 0);
+       }
+       return NULL;
+}
+
 // Serialize the given state to a file descriptor, and return the (still open)
 // descriptor.
 int make_tempfile(const CubemapStateProto &state)
@@ -201,8 +264,8 @@ int main(int argc, char **argv)
        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.
+       int port = fetch_config_int(config, "port", 1, 65535, PARAMATER_MANDATORY);
+       int num_servers = fetch_config_int(config, "num_servers", 1, 20000, PARAMATER_MANDATORY);  // Insanely high max limit.
 
        servers = new ServerPool(num_servers);
 
@@ -282,6 +345,13 @@ int main(int argc, char **argv)
                server_sock = create_server_socket(port);
        }
 
+       // See if the user wants stats.
+       string stats_file = fetch_config_string(config, "stats_file", PARAMETER_OPTIONAL);
+       int stats_interval = fetch_config_int(config, "stats_interval", 1, INT_MAX, PARAMETER_OPTIONAL, -1);
+       if (stats_interval != -1 && stats_file.empty()) {
+               fprintf(stderr, "WARNING: 'stats_interval' given, but no 'stats_file'. No statistics will be written.\n");
+       }
+
        servers->run();
 
        pthread_t acceptor_thread;
@@ -324,6 +394,15 @@ int main(int argc, char **argv)
        // All deserialized inputs should now have been taken care of, one way or the other.
        assert(deserialized_inputs.empty());
 
+       // Start writing statistics.
+       pthread_t stats_thread;
+       StatsThreadParameters stats_parameters;  // Must live for as long as the stats thread does.
+       if (!stats_file.empty()) {
+               stats_parameters.stats_file = stats_file;
+               stats_parameters.stats_interval = stats_interval;
+               pthread_create(&stats_thread, NULL, stats_thread_run, &stats_parameters);
+       }
+
        signal(SIGHUP, hup);
 
        while (!hupped) {
@@ -331,6 +410,12 @@ int main(int argc, char **argv)
        }
 
        // OK, we've been HUPed. Time to shut down everything, serialize, and re-exec.
+       if (!stats_file.empty()) {
+               if (pthread_join(stats_thread, NULL) == -1) {
+                       perror("pthread_join");
+                       exit(1);
+               }
+       }
        if (pthread_join(acceptor_thread, NULL) == -1) {
                perror("pthread_join");
                exit(1);