#include "liblttsessiondcomm.h"
#include "ltt-sessiond.h"
+const char default_home_dir[] = DEFAULT_HOME_DIR;
+const char default_tracing_group[] = DEFAULT_TRACING_GROUP;
+const char default_ust_sock_dir[] = DEFAULT_UST_SOCK_DIR;
+const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE;
+
/* Static functions */
static int set_signal_handler(void);
static int set_socket_perms(void);
static void sighandler(int);
-static void daemonize(void);
static void cleanup(void);
+static void copy_common_data(struct lttcomm_lttng_msg *llm, struct lttcomm_session_msg *lsm);
static int check_existing_daemon(void);
static int notify_apps(const char*);
static int connect_app(pid_t);
static int init_daemon_socket(void);
-static struct lttcomm_lttng_msg *process_client_msg(struct lttcomm_session_msg*);
+static int process_client_msg(int sock, struct lttcomm_session_msg*);
+static int send_unix_sock(int sock, void *buf, size_t len);
+static size_t ust_list_apps(pid_t **pids);
static void *thread_manage_clients(void *);
static void *thread_manage_apps(void *);
/* Variables */
const char *progname;
const char *opt_tracing_group;
+static int opt_sig_parent;
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 int apps_socket;
static struct ltt_session *current_session;
-static int session_count;
+
+/* Number of element for the list below. */
+static unsigned int session_count;
+static unsigned int traceable_app_count;
/* Init session's list */
static struct ltt_session_list ltt_session_list = {
.head = CDS_LIST_HEAD_INIT(ltt_session_list.head),
};
+/* Init ust traceabl application's list */
static struct ltt_traceable_app_list ltt_traceable_app_list = {
.head = CDS_LIST_HEAD_INIT(ltt_traceable_app_list.head),
};
struct ltt_traceable_app *lta;
/* TODO: Something more elegant is needed but fine for now */
- struct {
+ struct {
int reg; /* 1:register, 0:unregister */
- pid_t pid;
- uid_t uid;
- } reg_msg;
+ pid_t pid;
+ uid_t uid;
+ } reg_msg;
/* Notify all applications to register */
notify_apps(default_global_apps_pipe);
lta->pid = reg_msg.pid;
lta->uid = reg_msg.uid;
cds_list_add(<a->list, <t_traceable_app_list.head);
+ traceable_app_count++;
} else {
/* Unregistering */
lta = NULL;
cds_list_for_each_entry(lta, <t_traceable_app_list.head, list) {
if (lta->pid == reg_msg.pid && lta->uid == reg_msg.uid) {
cds_list_del(<a->list);
+ /* Check to not overflow here */
+ if (traceable_app_count != 0) {
+ traceable_app_count--;
+ }
break;
}
}
{
int sock, ret;
struct lttcomm_session_msg lsm;
- struct lttcomm_lttng_msg *llm;
ret = lttcomm_listen_unix_sock(client_socket);
if (ret < 0) {
goto error;
}
+ /* Notify parent pid that we are ready
+ * to accept command for client side.
+ */
+ if (opt_sig_parent) {
+ kill(ppid, SIGCHLD);
+ }
+
while (1) {
/* Blocking call, waiting for transmission */
sock = lttcomm_accept_unix_sock(client_socket);
}
/* This function dispatch the work to the LTTng or UST libs
- * and make sure that the reply structure (llm) is filled.
- */
- llm = process_client_msg(&lsm);
-
- /* Having a valid lttcomm_lttng_msg struct, reply is sent back
- * to the client directly.
+ * and then sends back the response to the client. This is needed
+ * because there might be more then one lttcomm_lttng_msg to
+ * send out so process_client_msg do both jobs.
*/
- if (llm != NULL) {
- ret = lttcomm_send_unix_sock(sock, llm,
- sizeof(struct lttcomm_lttng_msg));
- free(llm);
- if (ret < 0) {
- continue;
- }
- } else {
- /* The lttcomm_lttng_msg struct was not allocated
- * correctly. Fatal error since the daemon is not able
- * to respond. However, we still permit client connection.
- *
- * TODO: We should have a default llm that tells the client
- * that the sessiond had a fatal error and thus the client could
- * take action to restart ltt-sessiond or inform someone.
- */
+ ret = process_client_msg(sock, &lsm);
+ if (ret < 0) {
+ /* Error detected but still accept command */
+ continue;
}
}
return NULL;
}
+/*
+ * send_unix_sock
+ *
+ * Send data on a unix socket using the liblttsessiondcomm API.
+ *
+ * Return lttcomm error code.
+ */
+static int send_unix_sock(int sock, void *buf, size_t len)
+{
+ /* Check valid length */
+ if (len <= 0) {
+ return -1;
+ }
+
+ return lttcomm_send_unix_sock(sock, buf, len);
+}
+
/*
* connect_app
*
*
* Return size of the array.
*/
-static size_t ust_list_apps(pid_t *pids)
+static size_t ust_list_apps(pid_t **pids)
{
size_t size = 0;
struct ltt_traceable_app *iter = NULL;
+ pid_t *p;
- cds_list_for_each_entry(iter, <t_traceable_app_list.head, list) {
- if (size >= MAX_APPS_PID) {
- break;
- }
+ if (traceable_app_count == 0) {
+ /* No dynamic allocation is done */
+ goto end;
+ }
+
+ p = malloc(sizeof(pid_t) * traceable_app_count);
- pids[size] = iter->pid;
+ /* TODO: Mutex needed to access this list */
+ cds_list_for_each_entry(iter, <t_traceable_app_list.head, list) {
+ p[size] = iter->pid;
size++;
}
+ *pids = p;
+
+end:
return size;
}
+/*
+ * copy_common_data
+ *
+ * Copy common data between lttcomm_lttng_msg and lttcomm_session_msg
+ */
+static void copy_common_data(struct lttcomm_lttng_msg *llm, struct lttcomm_session_msg *lsm)
+{
+ llm->cmd_type = lsm->cmd_type;
+ llm->pid = lsm->pid;
+ if (!uuid_is_null(lsm->session_id)) {
+ uuid_copy(llm->session_id, lsm->session_id);
+ }
+ strncpy(llm->trace_name, lsm->trace_name, sizeof(llm->trace_name));
+}
+
/*
* process_client_msg
*
* This takes the lttcomm_session_msg struct and process the command requested
- * by the client. It then creates the reply by allocating a lttcomm_lttng_msg
- * and fill it with the necessary information.
+ * by the client. It then creates response(s) and send it back to the
+ * given socket (sock).
*
- * It's the caller responsability to free that structure when done with it.
- *
- * Return pointer to lttcomm_lttng_msg allocated struct.
+ * Return any error encountered or 0 for success.
*/
-static struct lttcomm_lttng_msg *process_client_msg(struct lttcomm_session_msg *lsm)
+static int process_client_msg(int sock, struct lttcomm_session_msg *lsm)
{
- struct lttcomm_lttng_msg *llm;
-
- /* Allocate the reply message structure */
- llm = malloc(sizeof(struct lttcomm_lttng_msg));
- if (llm == NULL) {
- perror("malloc");
- goto end;
- }
+ int ret;
+ struct lttcomm_lttng_msg llm;
/* Copy common data to identify the response
* on the lttng client side.
*/
- llm->cmd_type = lsm->cmd_type;
- llm->pid = lsm->pid;
- if (!uuid_is_null(lsm->session_id)) {
- uuid_copy(llm->session_id, lsm->session_id);
- }
- strncpy(llm->trace_name, lsm->trace_name, sizeof(llm->trace_name));
+ copy_common_data(&llm, lsm);
/* Default return code.
- * In a our world, everything is OK... right?
+ * In our world, everything is OK... right? ;)
*/
- llm->ret_code = LTTCOMM_OK;
+ llm.ret_code = LTTCOMM_OK;
/* Process by command type */
switch (lsm->cmd_type) {
case UST_LIST_APPS:
{
- llm->u.list_apps.size = ust_list_apps(llm->u.list_apps.pids);
+ pid_t *pids;
+ llm.num_pckt = ust_list_apps(&pids);
+ if (llm.num_pckt == 0) {
+ ret = LTTCOMM_NO_APPS;
+ goto error;
+ }
+
+ /* Send all packets */
+ while (llm.num_pckt != 0) {
+ llm.u.list_apps.pid = pids[traceable_app_count - llm.num_pckt];
+ ret = send_unix_sock(sock, (void*) &llm, sizeof(llm));
+ if (ret < 0) {
+ goto send_error;
+ }
+ llm.num_pckt--;
+ }
+ /* Allocated array by ust_list_apps() */
+ free(pids);
+
+ break;
+ }
+ case LTTNG_LIST_SESSIONS:
+ {
+ struct ltt_session *iter = NULL;
+
+ llm.num_pckt = session_count;
+ if (llm.num_pckt == 0) {
+ ret = LTTCOMM_NO_SESS;
+ goto error;
+ }
+
+ cds_list_for_each_entry(iter, <t_session_list.head, list) {
+ uuid_unparse(iter->uuid, llm.u.list_sessions.uuid);
+ strncpy(llm.u.list_sessions.name, iter->name,
+ sizeof(llm.u.list_sessions.name));
+ ret = send_unix_sock(sock, (void*) &llm, sizeof(llm));
+ if (ret < 0) {
+ goto send_error;
+ }
+ llm.num_pckt--;
+ }
+
break;
}
default:
+ {
/* Undefined command */
- llm->ret_code = LTTCOMM_UND;
+ ret = LTTCOMM_UND;
break;
+ }
}
-end:
- return llm;
+ return 0;
+
+send_error:
+ return ret;
+
+error:
+ /* Notify client of error */
+ llm.ret_code = ret;
+ send_unix_sock(sock, (void*) &llm, sizeof(llm));
+
+ return -1;
}
/*
"\t-a, --apps-sock PATH\t\tSpecify path for apps unix socket.\n"
"\t-d, --daemonize\t\tStart as a daemon.\n"
"\t-g, --group NAME\t\tSpecify the tracing group name. (default: tracing)\n"
- "\t-V, --version\t\tShow version number.\n",
+ "\t-V, --version\t\tShow version number.\n"
+ "\t-S, --sig-parent\t\tSend SIGCHLD to parent pid to notify readiness.\n",
progname);
}
{ "client-sock", 1, 0, 'c' },
{ "apps-sock", 1, 0, 'a' },
{ "daemonize", 0, 0, 'd' },
+ { "sig-parent", 0, 0, 'S' },
{ "help", 0, 0, 'h' },
{ "group", 1, 0, 'g' },
{ "version", 0, 0, 'V' },
while (1) {
int option_index = 0;
- c = getopt_long(argc, argv, "dhV" "a:c:g:s:", long_options, &option_index);
+ c = getopt_long(argc, argv, "dhVS" "a:c:g:s:", long_options, &option_index);
if (c == -1) {
break;
}
case 'V':
fprintf(stdout, "%s\n", VERSION);
exit(EXIT_SUCCESS);
+ case 'S':
+ opt_sig_parent = 1;
+ break;
default:
/* Unknown option or other error.
* Error is printed by getopt, just return */
{
const char *home_path;
- if ((home_path = (const char*) getenv("HOME")) == NULL) {
+ if ((home_path = (const char *) getenv("HOME")) == NULL) {
home_path = default_home_dir;
}
return ret;
}
-/*
- * daemonize
- *
- * Daemonize ltt-sessiond.
- */
-static void daemonize(void)
-{
- pid_t pid, sid;
- const char *home_dir = get_home_dir();
-
- /* Fork off the parent process */
- if ((pid = fork()) < 0) {
- perror("fork");
- exit(EXIT_FAILURE);
- }
-
- /* Parent can now exit */
- if (pid > 0) {
- exit(EXIT_SUCCESS);
- }
-
- /* Change the file mode mask */
- umask(0);
-
- /* Create a new SID for the child process */
- if ((sid = setsid()) < 0) {
- perror("setsid");
- exit(EXIT_FAILURE);
- }
-
- /* Change the current working directory */
- if ((chdir(home_dir)) < 0) {
- perror("chdir");
- exit(EXIT_FAILURE);
- }
-
- /* Close out the standard file descriptors */
- close(STDIN_FILENO);
- close(STDOUT_FILENO);
- close(STDERR_FILENO);
-}
-
/*
* set_signal_handler
*
case SIGINT:
case SIGTERM:
cleanup();
+ break;
default:
break;
}
/* Daemonize */
if (opt_daemon) {
- daemonize();
+ ret = daemon(0, 0);
+ if (ret < 0) {
+ perror("daemon");
+ goto error;
+ }
}
/* Check if daemon is UID = 0 */
goto error;
}
+ /* Get parent pid if -S, --sig-parent is specified. */
+ if (opt_sig_parent) {
+ ppid = getppid();
+ }
+
while (1) {
/* Create thread to manage the client socket */
ret = pthread_create(&threads[0], NULL, thread_manage_clients, (void *) NULL);
projects / lttng-tools.git / blobdiff