Add kconsumerd thread function and sockets

Adds the first part of the kconsumerd thread and setup the sockets.

This patch moves every sockets of the sessiond (run as root) to
/var/run/lttng.

Fix various comments and function name to make things clearer.

Signed-off-by: David Goulet <david.goulet@polymtl.ca>

diff --git a/liblttsessiondcomm/liblttsessiondcomm.h b/liblttsessiondcomm/liblttsessiondcomm.h
index 0993b76c819db939cc8f306acb2e38ad589a3bc7..967c77c206c24c400feb090d37da7c108c96dc3f 100644 (file)
--- a/liblttsessiondcomm/liblttsessiondcomm.h
+++ b/liblttsessiondcomm/liblttsessiondcomm.h
@@ -22,12 +22,19 @@
 #include <limits.h>
 #include <uuid/uuid.h>
 
+#define LTTNG_RUNDIR                                           "/var/run/lttng"
+
 /* Default unix socket path */
-#define DEFAULT_GLOBAL_CLIENT_UNIX_SOCK                "/tmp/client-ltt-sessiond"
-#define DEFAULT_GLOBAL_APPS_UNIX_SOCK          "/tmp/apps-ltt-sessiond"
+#define DEFAULT_GLOBAL_CLIENT_UNIX_SOCK                LTTNG_RUNDIR "/client-ltt-sessiond"
+#define DEFAULT_GLOBAL_APPS_UNIX_SOCK          LTTNG_RUNDIR "/apps-ltt-sessiond"
 #define DEFAULT_HOME_APPS_UNIX_SOCK                    "%s/.apps-ltt-sessiond"
 #define DEFAULT_HOME_CLIENT_UNIX_SOCK          "%s/.client-ltt-sessiond"
 
+/* Kernel consumer path */
+#define KCONSUMERD_PATH                                                LTTNG_RUNDIR "/kconsumerd"
+#define KCONSUMERD_CMD_SOCK_PATH                       KCONSUMERD_PATH "/command"
+#define KCONSUMERD_ERR_SOCK_PATH                       KCONSUMERD_PATH "/error"
+
 /* Queue size of listen(2) */
 #define MAX_LISTEN 10
 

diff --git a/ltt-sessiond/main.c b/ltt-sessiond/main.c
index 241a1cffd32533ee56f11299e7748b043b4a7da1..f2205e4b12edd2f39f407f8be74afae8aa0ee992 100644 (file)
--- a/ltt-sessiond/main.c
+++ b/ltt-sessiond/main.c
@@ -58,14 +58,17 @@ static int notify_apps(const char* name);
 static int process_client_msg(int sock, struct lttcomm_session_msg*);
 static int send_unix_sock(int sock, void *buf, size_t len);
 static int set_signal_handler(void);
-static int set_socket_perms(void);
+static int set_permissions(void);
 static int setup_data_buffer(char **buf, size_t size, struct lttcomm_lttng_msg *llm);
+static int create_lttng_rundir(void);
+static int set_kconsumerd_sockets(void);
 static void cleanup(void);
 static void copy_common_data(struct lttcomm_lttng_msg *llm, struct lttcomm_session_msg *lsm);
 static void sighandler(int sig);
 
 static void *thread_manage_clients(void *data);
 static void *thread_manage_apps(void *data);
+static void *thread_manage_kconsumerd(void *data);
 
 /* Variables */
 int opt_verbose;
@@ -77,14 +80,51 @@ static int opt_daemon;
 static int is_root;                    /* Set to 1 if the daemon is running as root */
 static pid_t ppid;
 
-static char apps_unix_sock_path[PATH_MAX];                     /* Global application Unix socket path */
-static char client_unix_sock_path[PATH_MAX];           /* Global client Unix socket path */
+static char apps_unix_sock_path[PATH_MAX];                             /* Global application Unix socket path */
+static char client_unix_sock_path[PATH_MAX];                   /* Global client Unix socket path */
+static char kconsumerd_err_unix_sock_path[PATH_MAX];   /* kconsumerd error Unix socket path */
+static char kconsumerd_cmd_unix_sock_path[PATH_MAX];   /* kconsumerd command Unix socket path */
 
-static int client_socket;
-static int apps_socket;
+static int client_sock;
+static int apps_sock;
+static int kconsumerd_err_sock;
 
 static struct ltt_session *current_session;
 
+/*
+ *  thread_manage_kconsumerd
+ *
+ *  This thread manage the kconsumerd error sent
+ *  back to the session daemon.
+ */
+static void *thread_manage_kconsumerd(void *data)
+{
+       int sock, ret;
+
+       DBG("[thread] Manage kconsumerd started");
+
+       ret = lttcomm_listen_unix_sock(kconsumerd_err_sock);
+       if (ret < 0) {
+               goto error;
+       }
+
+       sock = lttcomm_accept_unix_sock(kconsumerd_err_sock);
+       if (sock < 0) {
+               goto error;
+       }
+
+       while (1) {
+               //ret = lttcomm_recv_unix_sock(sock, &lsm, sizeof(lsm));
+               if (ret <= 0) {
+                       /* TODO: Consumerd died? */
+                       continue;
+               }
+       }
+
+error:
+       return NULL;
+}
+
 /*
  *     thread_manage_apps
  *
@@ -106,14 +146,14 @@ static void *thread_manage_apps(void *data)
        /* Notify all applications to register */
        notify_apps(default_global_apps_pipe);
 
-       ret = lttcomm_listen_unix_sock(apps_socket);
+       ret = lttcomm_listen_unix_sock(apps_sock);
        if (ret < 0) {
                goto error;
        }
 
        while (1) {
                /* Blocking call, waiting for transmission */
-               sock = lttcomm_accept_unix_sock(apps_socket);
+               sock = lttcomm_accept_unix_sock(apps_sock);
                if (sock < 0) {
                        goto error;
                }
@@ -161,7 +201,7 @@ static void *thread_manage_clients(void *data)
 
        DBG("[thread] Manage client started");
 
-       ret = lttcomm_listen_unix_sock(client_socket);
+       ret = lttcomm_listen_unix_sock(client_sock);
        if (ret < 0) {
                goto error;
        }
@@ -175,7 +215,7 @@ static void *thread_manage_clients(void *data)
 
        while (1) {
                /* Blocking call, waiting for transmission */
-               sock = lttcomm_accept_unix_sock(client_socket);
+               sock = lttcomm_accept_unix_sock(client_sock);
                if (sock < 0) {
                        goto error;
                }
@@ -661,15 +701,17 @@ end:
 static void usage(void)
 {
        fprintf(stderr, "Usage: %s OPTIONS\n\nOptions:\n", progname);
-       fprintf(stderr, "  -h, --help                Display this usage.\n");
-       fprintf(stderr, "  -c, --client-sock PATH    Specify path for the client unix socket\n");
-       fprintf(stderr, "  -a, --apps-sock PATH      Specify path for apps unix socket.\n");
-       fprintf(stderr, "  -d, --daemonize           Start as a daemon.\n");
-       fprintf(stderr, "  -g, --group NAME          Specify the tracing group name. (default: tracing)\n");
-       fprintf(stderr, "  -V, --version             Show version number.\n");
-       fprintf(stderr, "  -S, --sig-parent          Send SIGCHLD to parent pid to notify readiness.\n");
-       fprintf(stderr, "  -q, --quiet               No output at all.\n");
-       fprintf(stderr, "  -v, --verbose             Verbose mode. Activate DBG() macro.\n");
+       fprintf(stderr, "  -h, --help                         Display this usage.\n");
+       fprintf(stderr, "  -c, --client-sock PATH             Specify path for the client unix socket\n");
+       fprintf(stderr, "  -a, --apps-sock PATH               Specify path for apps unix socket\n");
+       fprintf(stderr, "      --kconsumerd-err-sock PATH     Specify path for the kernel consumer error socket\n");
+       fprintf(stderr, "      --kconsumerd-cmd-sock PATH     Specify path for the kernel consumer command socket\n");
+       fprintf(stderr, "  -d, --daemonize                    Start as a daemon.\n");
+       fprintf(stderr, "  -g, --group NAME                   Specify the tracing group name. (default: tracing)\n");
+       fprintf(stderr, "  -V, --version                      Show version number.\n");
+       fprintf(stderr, "  -S, --sig-parent                   Send SIGCHLD to parent pid to notify readiness.\n");
+       fprintf(stderr, "  -q, --quiet                        No output at all.\n");
+       fprintf(stderr, "  -v, --verbose                      Verbose mode. Activate DBG() macro.\n");
 }
 
 /*
@@ -682,6 +724,8 @@ static int parse_args(int argc, char **argv)
        static struct option long_options[] = {
                { "client-sock", 1, 0, 'c' },
                { "apps-sock", 1, 0, 'a' },
+               { "kconsumerd-cmd-sock", 1, 0, 0 },
+               { "kconsumerd-err-sock", 1, 0, 0 },
                { "daemonize", 0, 0, 'd' },
                { "sig-parent", 0, 0, 'S' },
                { "help", 0, 0, 'h' },
@@ -694,7 +738,7 @@ static int parse_args(int argc, char **argv)
 
        while (1) {
                int option_index = 0;
-               c = getopt_long(argc, argv, "dhqvVS" "a:c:g:s:", long_options, &option_index);
+               c = getopt_long(argc, argv, "dhqvVS" "a:c:g:s:E:C:", long_options, &option_index);
                if (c == -1) {
                        break;
                }
@@ -727,6 +771,12 @@ static int parse_args(int argc, char **argv)
                case 'S':
                        opt_sig_parent = 1;
                        break;
+               case 'E':
+                       snprintf(kconsumerd_err_unix_sock_path, PATH_MAX, "%s", optarg);
+                       break;
+               case 'C':
+                       snprintf(kconsumerd_cmd_unix_sock_path, PATH_MAX, "%s", optarg);
+                       break;
                case 'q':
                        opt_quiet = 1;
                        break;
@@ -747,8 +797,8 @@ static int parse_args(int argc, char **argv)
  *     init_daemon_socket
  *
  *     Creates the two needed socket by the daemon.
- *         apps_socket - The communication socket for all UST apps.
- *         client_socket - The communication of the cli tool (lttng).
+ *         apps_sock - The communication socket for all UST apps.
+ *         client_sock - The communication of the cli tool (lttng).
  */
 static int init_daemon_socket()
 {
@@ -758,8 +808,9 @@ static int init_daemon_socket()
        old_umask = umask(0);
 
        /* Create client tool unix socket */
-       client_socket = lttcomm_create_unix_sock(client_unix_sock_path);
-       if (client_socket < 0) {
+       client_sock = lttcomm_create_unix_sock(client_unix_sock_path);
+       if (client_sock < 0) {
+               ERR("Create unix sock failed: %s", client_unix_sock_path);
                ret = -1;
                goto end;
        }
@@ -767,20 +818,23 @@ static int init_daemon_socket()
        /* File permission MUST be 660 */
        ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
        if (ret < 0) {
+               ERR("Set file permissions failed: %s", client_unix_sock_path);
                perror("chmod");
                goto end;
        }
 
        /* Create the application unix socket */
-       apps_socket = lttcomm_create_unix_sock(apps_unix_sock_path);
-       if (apps_socket < 0) {
+       apps_sock = lttcomm_create_unix_sock(apps_unix_sock_path);
+       if (apps_sock < 0) {
+               ERR("Create unix sock failed: %s", apps_unix_sock_path);
                ret = -1;
                goto end;
        }
 
-       /* File permission MUST be 660 */
+       /* File permission MUST be 666 */
        ret = chmod(apps_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH);
        if (ret < 0) {
+               ERR("Set file permissions failed: %s", apps_unix_sock_path);
                perror("chmod");
                goto end;
        }
@@ -828,11 +882,11 @@ static const char *get_home_dir(void)
 }
 
 /*
- *  set_socket_perms
+ *  set_permissions
  *
  *     Set the tracing group gid onto the client socket.
  */
-static int set_socket_perms(void)
+static int set_permissions(void)
 {
        int ret;
        struct group *grp;
@@ -848,17 +902,97 @@ static int set_socket_perms(void)
                goto end;
        }
 
+       /* Set lttng run dir */
+       ret = chown(LTTNG_RUNDIR, 0, grp->gr_gid);
+       if (ret < 0) {
+               ERR("Unable to set group on " LTTNG_RUNDIR);
+               perror("chown");
+       }
+
+       /* lttng client socket path */
        ret = chown(client_unix_sock_path, 0, grp->gr_gid);
        if (ret < 0) {
+               ERR("Unable to set group on %s", client_unix_sock_path);
+               perror("chown");
+       }
+
+       /* kconsumerd error socket path */
+       ret = chown(kconsumerd_err_unix_sock_path, 0, grp->gr_gid);
+       if (ret < 0) {
+               ERR("Unable to set group on %s", kconsumerd_err_unix_sock_path);
                perror("chown");
        }
 
-       DBG("Sockets permissions set");
+       DBG("All permissions are set");
 
 end:
        return ret;
 }
 
+/*
+ *  create_lttng_rundir
+ *
+ *  Create the lttng run directory needed for all
+ *  global sockets and pipe.
+ */
+static int create_lttng_rundir(void)
+{
+       int ret;
+
+       ret = mkdir(LTTNG_RUNDIR, S_IRWXU | S_IRWXG );
+       if (ret < 0) {
+               ERR("Unable to create " LTTNG_RUNDIR);
+               goto error;
+       }
+
+error:
+       return ret;
+}
+
+/*
+ *  set_kconsumerd_sockets
+ *
+ *  Setup sockets and directory needed by the kconsumerd
+ *  communication with the session daemon.
+ */
+static int set_kconsumerd_sockets(void)
+{
+       int ret;
+
+       if (strlen(kconsumerd_err_unix_sock_path) == 0) {
+               snprintf(kconsumerd_err_unix_sock_path, PATH_MAX, KCONSUMERD_ERR_SOCK_PATH);
+       }
+
+       if (strlen(kconsumerd_cmd_unix_sock_path) == 0) {
+               snprintf(kconsumerd_cmd_unix_sock_path, PATH_MAX, KCONSUMERD_CMD_SOCK_PATH);
+       }
+
+       ret = mkdir(KCONSUMERD_PATH, S_IRWXU | S_IRWXG);
+       if (ret < 0) {
+               ERR("Failed to create " KCONSUMERD_PATH);
+               goto error;
+       }
+
+       /* Create the kconsumerd error unix socket */
+       kconsumerd_err_sock = lttcomm_create_unix_sock(kconsumerd_err_unix_sock_path);
+       if (kconsumerd_err_sock < 0) {
+               ERR("Create unix sock failed: %s", kconsumerd_err_unix_sock_path);
+               ret = -1;
+               goto error;
+       }
+
+       /* File permission MUST be 660 */
+       ret = chmod(kconsumerd_err_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP);
+       if (ret < 0) {
+               ERR("Set file permissions failed: %s", kconsumerd_err_unix_sock_path);
+               perror("chmod");
+               goto error;
+       }
+
+error:
+       return ret;
+}
+
 /*
  *  set_signal_handler
  *
@@ -932,6 +1066,9 @@ static void sighandler(int sig)
  */
 static void cleanup()
 {
+       int ret;
+       char *cmd;
+
        DBG("Cleaning up");
 
        /* <fun> */
@@ -941,6 +1078,18 @@ static void cleanup()
 
        unlink(client_unix_sock_path);
        unlink(apps_unix_sock_path);
+       unlink(kconsumerd_err_unix_sock_path);
+
+       ret = asprintf(&cmd, "rm -rf " LTTNG_RUNDIR);
+       if (ret < 0) {
+               ERR("asprintf failed. Something is really wrong!");
+       }
+
+       /* Remove lttng run directory */
+       ret = system(cmd);
+       if (ret < 0) {
+               ERR("Unable to clean " LTTNG_RUNDIR);
+       }
 }
 
 /*
@@ -973,25 +1122,35 @@ int main(int argc, char **argv)
 
        /* Set all sockets path */
        if (is_root) {
+               ret = create_lttng_rundir();
+               if (ret < 0) {
+                       goto error;
+               }
+
                if (strlen(apps_unix_sock_path) == 0) {
-                       (snprintf(apps_unix_sock_path, PATH_MAX,
-                                       DEFAULT_GLOBAL_APPS_UNIX_SOCK));
+                       snprintf(apps_unix_sock_path, PATH_MAX,
+                                       DEFAULT_GLOBAL_APPS_UNIX_SOCK);
                }
 
                if (strlen(client_unix_sock_path) == 0) {
-                       (snprintf(client_unix_sock_path, PATH_MAX,
-                                       DEFAULT_GLOBAL_CLIENT_UNIX_SOCK));
+                       snprintf(client_unix_sock_path, PATH_MAX,
+                                       DEFAULT_GLOBAL_CLIENT_UNIX_SOCK);
+               }
+
+               ret = set_kconsumerd_sockets();
+               if (ret < 0) {
+                       goto error;
                }
        } else {
                if (strlen(apps_unix_sock_path) == 0) {
-                       (snprintf(apps_unix_sock_path, PATH_MAX,
-                                       DEFAULT_HOME_APPS_UNIX_SOCK, get_home_dir()));
+                       snprintf(apps_unix_sock_path, PATH_MAX,
+                                       DEFAULT_HOME_APPS_UNIX_SOCK, get_home_dir());
                }
 
                /* Set the cli tool unix socket path */
                if (strlen(client_unix_sock_path) == 0) {
-                       (snprintf(client_unix_sock_path, PATH_MAX,
-                                       DEFAULT_HOME_CLIENT_UNIX_SOCK, get_home_dir()));
+                       snprintf(client_unix_sock_path, PATH_MAX,
+                                       DEFAULT_HOME_CLIENT_UNIX_SOCK, get_home_dir());
                }
        }
 
@@ -1001,7 +1160,7 @@ int main(int argc, char **argv)
        if ((ret = check_existing_daemon()) == 0) {
                ERR("Already running daemon.\n");
                /* We do not goto error because we must not
-                * cleanup() because a daemon is already working.
+                * cleanup() because a daemon is already running.
                 */
                return EXIT_FAILURE;
        }
@@ -1010,13 +1169,13 @@ int main(int argc, char **argv)
                goto error;
        }
 
-       /* Setup the two needed unix socket */
+       /* Setup the needed unix socket */
        if (init_daemon_socket() < 0) {
                goto error;
        }
 
        /* Set credentials to socket */
-       if (is_root && (set_socket_perms() < 0)) {
+       if (is_root && (set_permissions() < 0)) {
                goto error;
        }