From: David Goulet Date: Fri, 29 Apr 2011 16:04:02 +0000 (-0400) Subject: Move session data and functions to session.c/.h X-Git-Tag: v2.0-pre1~167 X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=commitdiff_plain;h=5b74c7b1ca96399ba5c8bd0ce6974aea671198eb;ds=sidebyside Move session data and functions to session.c/.h Moving all session data to a specific C file. Basic changes to the code was necessary to make functions and variables non-static. Adds a get_session_count to protect direct changes to the session counter. Also, rename ltt-sessiond.c to main.c. Signed-off-by: David Goulet --- diff --git a/ltt-sessiond/Makefile.am b/ltt-sessiond/Makefile.am index 479309189..00c0e8958 100644 --- a/ltt-sessiond/Makefile.am +++ b/ltt-sessiond/Makefile.am @@ -1,8 +1,9 @@ AM_CPPFLAGS = -I$(top_srcdir)/include -I$(top_srcdir)/liblttsessiondcomm +AM_CFLAGS = -fno-strict-aliasing bin_PROGRAMS = ltt-sessiond -ltt_sessiond_SOURCES = ltt-sessiond.c +ltt_sessiond_SOURCES = session.c main.c ltt_sessiond_LDADD = \ $(top_builddir)/liblttsessiondcomm/liblttsessiondcomm.la diff --git a/ltt-sessiond/ltt-sessiond.c b/ltt-sessiond/ltt-sessiond.c deleted file mode 100644 index 4f9ca1bd4..000000000 --- a/ltt-sessiond/ltt-sessiond.c +++ /dev/null @@ -1,1210 +0,0 @@ -/* - * Copyright (C) 2011 - David Goulet - * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version 2 - * of the License, or (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. - */ - -#define _GNU_SOURCE -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include /* URCU list library (-lurcu) */ -#include /* UST control lib (-lust) */ -#include - -#include "liblttsessiondcomm.h" -#include "ltt-sessiond.h" -#include "lttngerr.h" - -/* Const values */ -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 sig); -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* name); -static int connect_app(pid_t pid); -static int find_app_by_pid(pid_t pid); -static int init_daemon_socket(void); -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 setup_data_buffer(char **buf, size_t size, struct lttcomm_lttng_msg *llm); -static void add_traceable_app(struct ltt_traceable_app *lta); -static void del_traceable_app(struct ltt_traceable_app *lta); -static void add_session_list(struct ltt_session *ls); -static void del_session_list(struct ltt_session *ls); - -/* Command function */ -static void get_list_apps(pid_t *pids); -static void get_list_sessions(struct lttng_session *lt); - -static void *thread_manage_clients(void *data); -static void *thread_manage_apps(void *data); - -static int create_session(char *name, uuid_t *session_id); -static int destroy_session(uuid_t *uuid); - -static struct ltt_session *find_session_by_uuid(uuid_t session_id); -static struct ltt_session *find_session_by_name(char *name); - -/* Variables */ -const char *progname; -const char *opt_tracing_group; -static int opt_sig_parent; -static int opt_daemon; -int opt_verbose; -int opt_quiet; -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 client_socket; -static int apps_socket; - -static struct ltt_session *current_session; - -/* 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), -}; - -/* List mutex */ -pthread_mutex_t ltt_traceable_app_list_mutex; - -/* - * thread_manage_apps - * - * This thread manage the application socket communication - */ -static void *thread_manage_apps(void *data) -{ - int sock, ret; - struct ltt_traceable_app *lta; - - /* TODO: Something more elegant is needed but fine for now */ - struct { - int reg; /* 1:register, 0:unregister */ - pid_t pid; - uid_t uid; - } reg_msg; - - /* Notify all applications to register */ - notify_apps(default_global_apps_pipe); - - ret = lttcomm_listen_unix_sock(apps_socket); - if (ret < 0) { - goto error; - } - - while (1) { - /* Blocking call, waiting for transmission */ - sock = lttcomm_accept_unix_sock(apps_socket); - if (sock < 0) { - goto error; - } - - /* Basic recv here to handle the very simple data - * that the libust send to register (reg_msg). - */ - ret = recv(sock, ®_msg, sizeof(reg_msg), 0); - if (ret < 0) { - perror("recv"); - continue; - } - - /* Add application to the global traceable list */ - if (reg_msg.reg == 1) { - /* Registering */ - lta = malloc(sizeof(struct ltt_traceable_app)); - lta->pid = reg_msg.pid; - lta->uid = reg_msg.uid; - add_traceable_app(lta); - } else { - /* Unregistering */ - cds_list_for_each_entry(lta, <t_traceable_app_list.head, list) { - if (lta->pid == reg_msg.pid && lta->uid == reg_msg.uid) { - del_traceable_app(lta); - free(lta); - break; - } - } - } - } - -error: - - return NULL; -} - -/* - * thread_manage_clients - * - * This thread manage all clients request using the unix - * client socket for communication. - */ -static void *thread_manage_clients(void *data) -{ - int sock, ret; - struct lttcomm_session_msg lsm; - - 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); - if (sock < 0) { - goto error; - } - - /* - * Data is received from the lttng client. The struct - * lttcomm_session_msg (lsm) contains the command and data - * request of the client. - */ - ret = lttcomm_recv_unix_sock(sock, &lsm, sizeof(lsm)); - if (ret <= 0) { - continue; - } - - /* This function dispatch the work to the LTTng or UST libs - * 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. - */ - ret = process_client_msg(sock, &lsm); - if (ret < 0) { - /* Error detected but still accept command */ - continue; - } - } - -error: - return NULL; -} - -/* - * add_traceable_app - * - * Add a traceable application structure to the global - * list protected by a mutex. - */ -static void add_traceable_app(struct ltt_traceable_app *lta) -{ - pthread_mutex_lock(<t_traceable_app_list_mutex); - cds_list_add(<a->list, <t_traceable_app_list.head); - traceable_app_count++; - pthread_mutex_unlock(<t_traceable_app_list_mutex); -} - -/* - * del_traceable_app - * - * Delete a traceable application structure from the - * global list protected by a mutex. - */ -static void del_traceable_app(struct ltt_traceable_app *lta) -{ - pthread_mutex_lock(<t_traceable_app_list_mutex); - cds_list_del(<a->list); - /* Sanity check */ - if (traceable_app_count != 0) { - traceable_app_count--; - } - pthread_mutex_unlock(<t_traceable_app_list_mutex); -} - -/* - * add_session_list - * - * Add a ltt_session structure to the global list. - */ -static void add_session_list(struct ltt_session *ls) -{ - cds_list_add(&ls->list, <t_session_list.head); - session_count++; -} - -/* - * del_session_list - * - * Delete a ltt_session structure to the global list. - */ -static void del_session_list(struct ltt_session *ls) -{ - cds_list_del(&ls->list); - /* Sanity check */ - if (session_count != 0) { - session_count--; - } -} - -/* - * 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 a socket connected to the libust communication socket - * of the application identified by the pid. - * - * If the pid is not found in the traceable list, - * return -1 to indicate error. - */ -static int connect_app(pid_t pid) -{ - int sock, ret; - - ret = find_app_by_pid(pid); - if (ret == 0) { - return -1; - } - - sock = ustctl_connect_pid(pid); - if (sock < 0) { - ERR("Fail connecting to the PID %d\n", pid); - } - - return sock; -} - -/* - * notify_apps - * - * Notify apps by writing 42 to a named pipe using name. - * Every applications waiting for a ltt-sessiond will be notified - * and re-register automatically to the session daemon. - * - * Return open or write error value. - */ -static int notify_apps(const char *name) -{ - int fd; - int ret = -1; - - /* Try opening the global pipe */ - fd = open(name, O_WRONLY); - if (fd < 0) { - goto error; - } - - /* Notify by writing on the pipe */ - ret = write(fd, "42", 2); - if (ret < 0) { - perror("write"); - } - -error: - return ret; -} - -/* - * find_app_by_pid - * - * Iterate over the traceable apps list. - * On success, return 1, else return 0 - */ -static int find_app_by_pid(pid_t pid) -{ - struct ltt_traceable_app *iter; - - pthread_mutex_lock(<t_traceable_app_list_mutex); - cds_list_for_each_entry(iter, <t_traceable_app_list.head, list) { - if (iter->pid == pid) { - pthread_mutex_unlock(<t_traceable_app_list_mutex); - /* Found */ - return 1; - } - } - pthread_mutex_unlock(<t_traceable_app_list_mutex); - - return 0; -} - -/* - * find_session_by_uuid - * - * Return a ltt_session structure ptr that matches the uuid. - */ -static struct ltt_session *find_session_by_uuid(uuid_t session_id) -{ - int found = 0; - struct ltt_session *iter; - - /* Sanity check for NULL session_id */ - if (uuid_is_null(session_id)) { - goto end; - } - - cds_list_for_each_entry(iter, <t_session_list.head, list) { - if (uuid_compare(iter->uuid, session_id) == 0) { - found = 1; - break; - } - } - -end: - if (!found) { - iter = NULL; - } - return iter; -} - -/* - * find_session_by_name - * - * Return a ltt_session structure ptr that matches name. - * If no session found, NULL is returned. - */ -static struct ltt_session *find_session_by_name(char *name) -{ - int found = 0; - struct ltt_session *iter; - - cds_list_for_each_entry(iter, <t_session_list.head, list) { - if (strncmp(iter->name, name, strlen(iter->name)) == 0) { - found = 1; - break; - } - } - - if (!found) { - iter = NULL; - } - - return iter; -} - -/* - * destroy_session - * - * Delete session from the global session list - * and free the memory. - * - * Return -1 if no session is found. - * On success, return 1; - */ -static int destroy_session(uuid_t *uuid) -{ - int found = -1; - struct ltt_session *iter; - - cds_list_for_each_entry(iter, <t_session_list.head, list) { - if (uuid_compare(iter->uuid, *uuid) == 0) { - del_session_list(iter); - free(iter); - found = 1; - break; - } - } - - return found; -} - -/* - * create_session - * - * Create a brand new session and add it to the - * global session list. - */ -static int create_session(char *name, uuid_t *session_id) -{ - struct ltt_session *new_session; - - new_session = find_session_by_name(name); - if (new_session != NULL) { - goto error; - } - - /* Allocate session data structure */ - new_session = malloc(sizeof(struct ltt_session)); - if (new_session == NULL) { - perror("malloc"); - goto error_mem; - } - - if (name != NULL) { - if (asprintf(&new_session->name, "%s", name) < 0) { - goto error_mem; - } - } else { - /* Generate session name based on the session count */ - if (asprintf(&new_session->name, "%s%d", "lttng-", session_count) < 0) { - goto error_mem; - } - } - - /* UUID generation */ - uuid_generate(new_session->uuid); - uuid_copy(*session_id, new_session->uuid); - - /* Set consumer (identifier) to 0. This means that there is - * NO consumer attach to that session yet. - */ - new_session->ust_consumer = 0; - new_session->lttng_consumer = 0; - - /* Init list */ - CDS_INIT_LIST_HEAD(&new_session->ust_traces); - CDS_INIT_LIST_HEAD(&new_session->lttng_traces); - - /* Add new session to the global session list */ - add_session_list(new_session); - - return 0; - -error: - return -1; - -error_mem: - return -ENOMEM; -} - -/* - * ust_create_trace - * - * Create an userspace trace using pid. - * This trace is then appended to the current session - * ust trace list. - */ -static int ust_create_trace(pid_t pid) -{ - int sock, ret; - struct ltt_ust_trace *trace; - - trace = malloc(sizeof(struct ltt_ust_trace)); - if (trace == NULL) { - perror("malloc"); - ret = -1; - goto error; - } - - /* Init */ - trace->pid = pid; - trace->shmid = 0; - - /* Connect to app using ustctl API */ - sock = connect_app(pid); - if (sock < 0) { - ret = LTTCOMM_NO_TRACEABLE; - goto error; - } - - ret = ustctl_create_trace(sock, "auto"); - if (ret < 0) { - ret = LTTCOMM_CREATE_FAIL; - goto error; - } - - /* Check if current session is valid */ - if (current_session) { - cds_list_add(&trace->list, ¤t_session->ust_traces); - } - -error: - return ret; -} - -/* - * get_list_apps - * - * List traceable user-space application and fill an - * array of pids. - */ -static void get_list_apps(pid_t *pids) -{ - int i = 0; - struct ltt_traceable_app *iter; - - /* Protected by a mutex here because the threads manage_client - * and manage_apps can access this list. - */ - pthread_mutex_lock(<t_traceable_app_list_mutex); - cds_list_for_each_entry(iter, <t_traceable_app_list.head, list) { - pids[i] = iter->pid; - i++; - } - pthread_mutex_unlock(<t_traceable_app_list_mutex); -} - -/* - * get_list_sessions - * - * List sessions and fill the data buffer. - */ -static void get_list_sessions(struct lttng_session *lt) -{ - int i = 0; - struct ltt_session *iter; - struct lttng_session lsess; - - /* Iterate over session list and append data after - * the control struct in the buffer. - */ - cds_list_for_each_entry(iter, <t_session_list.head, list) { - /* Copy name and uuid */ - uuid_unparse(iter->uuid, lsess.uuid); - strncpy(lsess.name, iter->name, sizeof(lsess.name)); - lsess.name[sizeof(lsess.name) - 1] = '\0'; - memcpy(<[i], &lsess, sizeof(lsess)); - i++; - /* Reset struct for next pass */ - memset(&lsess, 0, sizeof(lsess)); - } -} - -/* - * 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; - - /* Manage uuid */ - if (!uuid_is_null(lsm->session_id)) { - uuid_copy(llm->session_id, lsm->session_id); - } - - strncpy(llm->trace_name, lsm->trace_name, strlen(llm->trace_name)); - llm->trace_name[strlen(llm->trace_name) - 1] = '\0'; -} - -/* - * setup_data_buffer - * - * Setup the outgoing data buffer for the response - * data allocating the right amount of memory. - * - * Return total size of the buffer pointed by buf. - */ -static int setup_data_buffer(char **buf, size_t s_data, struct lttcomm_lttng_msg *llm) -{ - int ret = 0; - size_t buf_size; - - buf_size = sizeof(struct lttcomm_lttng_msg) + s_data; - *buf = malloc(buf_size); - if (*buf == NULL) { - perror("malloc"); - ret = -1; - goto error; - } - - /* Setup lttcomm_lttng_msg data and copy - * it to the newly allocated buffer. - */ - llm->size_payload = s_data; - memcpy(*buf, llm, sizeof(struct lttcomm_lttng_msg)); - - return buf_size; - -error: - return ret; -} - -/* - * process_client_msg - * - * This takes the lttcomm_session_msg struct and process the command requested - * by the client. It then creates response(s) and send it back to the - * given socket (sock). - * - * Return any error encountered or 0 for success. - */ -static int process_client_msg(int sock, struct lttcomm_session_msg *lsm) -{ - int ret; - int buf_size; - size_t header_size; - char *send_buf = NULL; - struct lttcomm_lttng_msg llm; - - /* Copy common data to identify the response - * on the lttng client side. - */ - copy_common_data(&llm, lsm); - - /* Check command that needs a session */ - if (lsm->cmd_type != LTTNG_CREATE_SESSION && - lsm->cmd_type != LTTNG_LIST_SESSIONS && - lsm->cmd_type != UST_LIST_APPS) - { - current_session = find_session_by_uuid(lsm->session_id); - if (current_session == NULL) { - ret = LTTCOMM_SELECT_SESS; - goto end; - } - } - - /* Default return code. - * In our world, everything is OK... right? ;) - */ - llm.ret_code = LTTCOMM_OK; - - header_size = sizeof(struct lttcomm_lttng_msg); - - /* Process by command type */ - switch (lsm->cmd_type) { - case LTTNG_CREATE_SESSION: - { - ret = create_session(lsm->session_name, &llm.session_id); - if (ret < 0) { - if (ret == -1) { - ret = LTTCOMM_EXIST_SESS; - } else { - ret = LTTCOMM_FATAL; - } - goto end; - } - - buf_size = setup_data_buffer(&send_buf, 0, &llm); - if (buf_size < 0) { - ret = LTTCOMM_FATAL; - goto end; - } - - break; - } - case LTTNG_DESTROY_SESSION: - { - ret = destroy_session(&lsm->session_id); - if (ret < 0) { - ret = LTTCOMM_NO_SESS; - } else { - ret = LTTCOMM_OK; - } - - /* No auxiliary data so only send the llm struct. */ - goto end; - } - case UST_CREATE_TRACE: - { - ret = ust_create_trace(lsm->pid); - if (ret < 0) { - ret = LTTCOMM_CREATE_FAIL; - goto end; - } - - /* No auxiliary data so only send the llm struct. */ - goto end; - } - case UST_LIST_APPS: - { - /* Stop right now if no apps */ - if (traceable_app_count == 0) { - ret = LTTCOMM_NO_APPS; - goto end; - } - - /* Setup data buffer and details for transmission */ - buf_size = setup_data_buffer(&send_buf, - sizeof(pid_t) * traceable_app_count, &llm); - if (buf_size < 0) { - ret = LTTCOMM_FATAL; - goto end; - } - - get_list_apps((pid_t *)(send_buf + header_size)); - - break; - } - case LTTNG_LIST_SESSIONS: - { - /* Stop right now if no session */ - if (session_count == 0) { - ret = LTTCOMM_NO_SESS; - goto end; - } - - /* Setup data buffer and details for transmission */ - buf_size = setup_data_buffer(&send_buf, - (sizeof(struct lttng_session) * session_count), &llm); - if (buf_size < 0) { - ret = LTTCOMM_FATAL; - goto end; - } - - get_list_sessions((struct lttng_session *)(send_buf + header_size)); - - break; - } - default: - { - /* Undefined command */ - ret = LTTCOMM_UND; - goto end; - } - } - - ret = send_unix_sock(sock, send_buf, buf_size); - - if (send_buf != NULL) { - free(send_buf); - } - - return ret; - -end: - /* Notify client of error */ - llm.ret_code = ret; - llm.size_payload = 0; - send_unix_sock(sock, (void*) &llm, sizeof(llm)); - - return ret; -} - -/* - * usage function on stderr - */ -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"); -} - -/* - * daemon argument parsing - */ -static int parse_args(int argc, char **argv) -{ - int c; - - static struct option long_options[] = { - { "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' }, - { "quiet", 0, 0, 'q' }, - { NULL, 0, 0, 0 } - }; - - while (1) { - int option_index = 0; - c = getopt_long(argc, argv, "dhqVS" "a:c:g:s:", long_options, &option_index); - if (c == -1) { - break; - } - - switch (c) { - case 0: - fprintf(stderr, "option %s", long_options[option_index].name); - if (optarg) { - fprintf(stderr, " with arg %s\n", optarg); - } - break; - case 'c': - snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg); - break; - case 'a': - snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg); - break; - case 'd': - opt_daemon = 1; - break; - case 'g': - opt_tracing_group = strdup(optarg); - break; - case 'h': - usage(); - exit(EXIT_FAILURE); - case 'V': - fprintf(stdout, "%s\n", VERSION); - exit(EXIT_SUCCESS); - case 'S': - opt_sig_parent = 1; - break; - case 'q': - opt_quiet = 1; - break; - default: - /* Unknown option or other error. - * Error is printed by getopt, just return */ - return -1; - } - } - - return 0; -} - -/* - * 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). - */ -static int init_daemon_socket() -{ - int ret = 0; - mode_t old_umask; - - old_umask = umask(0); - - /* Create client tool unix socket */ - client_socket = lttcomm_create_unix_sock(client_unix_sock_path); - if (client_socket < 0) { - ret = -1; - goto end; - } - - /* File permission MUST be 660 */ - ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP); - if (ret < 0) { - perror("chmod"); - goto end; - } - - /* Create the application unix socket */ - apps_socket = lttcomm_create_unix_sock(apps_unix_sock_path); - if (apps_socket < 0) { - ret = -1; - goto end; - } - - /* File permission MUST be 660 */ - ret = chmod(apps_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH); - if (ret < 0) { - perror("chmod"); - goto end; - } - -end: - umask(old_umask); - return ret; -} - -/* - * check_existing_daemon - * - * Check if the global socket is available. - * If yes, error is returned. - */ -static int check_existing_daemon() -{ - int ret; - - ret = access(client_unix_sock_path, F_OK); - if (ret == 0) { - ret = access(apps_unix_sock_path, F_OK); - } - - return ret; -} - -/* - * get_home_dir - * - * Return pointer to home directory path using - * the env variable HOME. - * - * Default : /tmp - */ -static const char *get_home_dir(void) -{ - const char *home_path; - - if ((home_path = (const char *) getenv("HOME")) == NULL) { - home_path = default_home_dir; - } - - return home_path; -} - -/* - * set_socket_perms - * - * Set the tracing group gid onto the client socket. - */ -static int set_socket_perms(void) -{ - int ret; - struct group *grp; - - /* Decide which group name to use */ - (opt_tracing_group != NULL) ? - (grp = getgrnam(opt_tracing_group)) : - (grp = getgrnam(default_tracing_group)); - - if (grp == NULL) { - ERR("Missing tracing group. Aborting execution.\n"); - ret = -1; - goto end; - } - - ret = chown(client_unix_sock_path, 0, grp->gr_gid); - if (ret < 0) { - perror("chown"); - } - -end: - return ret; -} - -/* - * set_signal_handler - * - * Setup signal handler for : - * SIGINT, SIGTERM, SIGPIPE - */ -static int set_signal_handler(void) -{ - int ret = 0; - struct sigaction sa; - sigset_t sigset; - - if ((ret = sigemptyset(&sigset)) < 0) { - perror("sigemptyset"); - return ret; - } - - sa.sa_handler = sighandler; - sa.sa_mask = sigset; - sa.sa_flags = 0; - if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) { - perror("sigaction"); - return ret; - } - - if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) { - perror("sigaction"); - return ret; - } - - if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) { - perror("sigaction"); - return ret; - } - - return ret; -} - -/** - * sighandler - * - * Signal handler for the daemon - */ -static void sighandler(int sig) -{ - switch (sig) { - case SIGPIPE: - return; - case SIGINT: - case SIGTERM: - cleanup(); - break; - default: - break; - } - - exit(EXIT_SUCCESS); -} - -/* - * cleanup - * - * Cleanup the daemon on exit - */ -static void cleanup() -{ - /* */ - MSG("\n%c[%d;%dm*** assert failed *** ==> %c[%dm", 27,1,31,27,0); - MSG("%c[%d;%dmMatthew, BEET driven development works!%c[%dm",27,1,33,27,0); - /* */ - - unlink(client_unix_sock_path); - unlink(apps_unix_sock_path); -} - -/* - * main - */ -int main(int argc, char **argv) -{ - int i; - int ret = 0; - void *status; - pthread_t threads[2]; - - /* Parse arguments */ - progname = argv[0]; - if ((ret = parse_args(argc, argv) < 0)) { - goto error; - } - - /* Daemonize */ - if (opt_daemon) { - ret = daemon(0, 0); - if (ret < 0) { - perror("daemon"); - goto error; - } - } - - /* Check if daemon is UID = 0 */ - is_root = !getuid(); - - /* Set all sockets path */ - if (is_root) { - if (strlen(apps_unix_sock_path) == 0) { - (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)); - } - } else { - if (strlen(apps_unix_sock_path) == 0) { - (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())); - } - } - - /* See if daemon already exist. If any of the two - * socket needed by the daemon are present, this test fails - */ - 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. - */ - return EXIT_FAILURE; - } - - if (set_signal_handler() < 0) { - goto error; - } - - /* Setup the two needed unix socket */ - if (init_daemon_socket() < 0) { - goto error; - } - - /* Set credentials to socket */ - if (is_root && (set_socket_perms() < 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); - if (ret != 0) { - perror("pthread_create"); - goto error; - } - - /* Create thread to manage application socket */ - ret = pthread_create(&threads[1], NULL, thread_manage_apps, (void *) NULL); - if (ret != 0) { - perror("pthread_create"); - goto error; - } - - for (i = 0; i < 2; i++) { - ret = pthread_join(threads[i], &status); - if (ret != 0) { - perror("pthread_join"); - goto error; - } - } - } - - cleanup(); - return 0; - -error: - cleanup(); - - return EXIT_FAILURE; -} diff --git a/ltt-sessiond/ltt-sessiond.h b/ltt-sessiond/ltt-sessiond.h index 6c0824b80..f01fa2e16 100644 --- a/ltt-sessiond/ltt-sessiond.h +++ b/ltt-sessiond/ltt-sessiond.h @@ -13,7 +13,6 @@ * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. - * */ #ifndef _LTT_SESSIOND_H @@ -49,11 +48,6 @@ struct ltt_ust_marker { char *channel; }; -/* Global session list */ -struct ltt_session_list { - struct cds_list_head head; -}; - /* Traceable application list */ struct ltt_traceable_app_list { struct cds_list_head head; @@ -70,18 +64,4 @@ struct ltt_traceable_app { uid_t uid; /* User ID that owns the apps */ }; -/* - * ltt-session - This data structure contains information needed - * to identify a tracing session for both LTTng and UST. - */ -struct ltt_session { - char *name; - struct cds_list_head list; - uuid_t uuid; - struct cds_list_head ust_traces; - struct cds_list_head lttng_traces; - pid_t ust_consumer; - pid_t lttng_consumer; -}; - #endif /* _LTT_SESSIOND_H */ diff --git a/ltt-sessiond/main.c b/ltt-sessiond/main.c new file mode 100644 index 000000000..418875a2a --- /dev/null +++ b/ltt-sessiond/main.c @@ -0,0 +1,1007 @@ +/* + * Copyright (C) 2011 - David Goulet + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include /* URCU list library (-lurcu) */ +#include /* UST control lib (-lust) */ +#include + +#include "liblttsessiondcomm.h" +#include "ltt-sessiond.h" +#include "lttngerr.h" +#include "session.h" + +/* Const values */ +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 sig); +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* name); +static int connect_app(pid_t pid); +static int find_app_by_pid(pid_t pid); +static int init_daemon_socket(void); +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 setup_data_buffer(char **buf, size_t size, struct lttcomm_lttng_msg *llm); +static void add_traceable_app(struct ltt_traceable_app *lta); +static void del_traceable_app(struct ltt_traceable_app *lta); + +/* Command function */ +static void get_list_apps(pid_t *pids); + +static void *thread_manage_clients(void *data); +static void *thread_manage_apps(void *data); + +/* Variables */ +const char *progname; +const char *opt_tracing_group; +static int opt_sig_parent; +static int opt_daemon; +int opt_verbose; +int opt_quiet; +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 client_socket; +static int apps_socket; + +static struct ltt_session *current_session; + +/* Number of element for the list below. */ +static unsigned int traceable_app_count; + +/* 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), +}; + +/* List mutex */ +pthread_mutex_t ltt_traceable_app_list_mutex; + +/* + * thread_manage_apps + * + * This thread manage the application socket communication + */ +static void *thread_manage_apps(void *data) +{ + int sock, ret; + struct ltt_traceable_app *lta; + + /* TODO: Something more elegant is needed but fine for now */ + struct { + int reg; /* 1:register, 0:unregister */ + pid_t pid; + uid_t uid; + } reg_msg; + + /* Notify all applications to register */ + notify_apps(default_global_apps_pipe); + + ret = lttcomm_listen_unix_sock(apps_socket); + if (ret < 0) { + goto error; + } + + while (1) { + /* Blocking call, waiting for transmission */ + sock = lttcomm_accept_unix_sock(apps_socket); + if (sock < 0) { + goto error; + } + + /* Basic recv here to handle the very simple data + * that the libust send to register (reg_msg). + */ + ret = recv(sock, ®_msg, sizeof(reg_msg), 0); + if (ret < 0) { + perror("recv"); + continue; + } + + /* Add application to the global traceable list */ + if (reg_msg.reg == 1) { + /* Registering */ + lta = malloc(sizeof(struct ltt_traceable_app)); + lta->pid = reg_msg.pid; + lta->uid = reg_msg.uid; + add_traceable_app(lta); + } else { + /* Unregistering */ + cds_list_for_each_entry(lta, <t_traceable_app_list.head, list) { + if (lta->pid == reg_msg.pid && lta->uid == reg_msg.uid) { + del_traceable_app(lta); + free(lta); + break; + } + } + } + } + +error: + + return NULL; +} + +/* + * thread_manage_clients + * + * This thread manage all clients request using the unix + * client socket for communication. + */ +static void *thread_manage_clients(void *data) +{ + int sock, ret; + struct lttcomm_session_msg lsm; + + 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); + if (sock < 0) { + goto error; + } + + /* + * Data is received from the lttng client. The struct + * lttcomm_session_msg (lsm) contains the command and data + * request of the client. + */ + ret = lttcomm_recv_unix_sock(sock, &lsm, sizeof(lsm)); + if (ret <= 0) { + continue; + } + + /* This function dispatch the work to the LTTng or UST libs + * 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. + */ + ret = process_client_msg(sock, &lsm); + if (ret < 0) { + /* Error detected but still accept command */ + continue; + } + } + +error: + return NULL; +} + +/* + * add_traceable_app + * + * Add a traceable application structure to the global + * list protected by a mutex. + */ +static void add_traceable_app(struct ltt_traceable_app *lta) +{ + pthread_mutex_lock(<t_traceable_app_list_mutex); + cds_list_add(<a->list, <t_traceable_app_list.head); + traceable_app_count++; + pthread_mutex_unlock(<t_traceable_app_list_mutex); +} + +/* + * del_traceable_app + * + * Delete a traceable application structure from the + * global list protected by a mutex. + */ +static void del_traceable_app(struct ltt_traceable_app *lta) +{ + pthread_mutex_lock(<t_traceable_app_list_mutex); + cds_list_del(<a->list); + /* Sanity check */ + if (traceable_app_count != 0) { + traceable_app_count--; + } + pthread_mutex_unlock(<t_traceable_app_list_mutex); +} + +/* + * 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 a socket connected to the libust communication socket + * of the application identified by the pid. + * + * If the pid is not found in the traceable list, + * return -1 to indicate error. + */ +static int connect_app(pid_t pid) +{ + int sock, ret; + + ret = find_app_by_pid(pid); + if (ret == 0) { + return -1; + } + + sock = ustctl_connect_pid(pid); + if (sock < 0) { + ERR("Fail connecting to the PID %d\n", pid); + } + + return sock; +} + +/* + * notify_apps + * + * Notify apps by writing 42 to a named pipe using name. + * Every applications waiting for a ltt-sessiond will be notified + * and re-register automatically to the session daemon. + * + * Return open or write error value. + */ +static int notify_apps(const char *name) +{ + int fd; + int ret = -1; + + /* Try opening the global pipe */ + fd = open(name, O_WRONLY); + if (fd < 0) { + goto error; + } + + /* Notify by writing on the pipe */ + ret = write(fd, "42", 2); + if (ret < 0) { + perror("write"); + } + +error: + return ret; +} + +/* + * find_app_by_pid + * + * Iterate over the traceable apps list. + * On success, return 1, else return 0 + */ +static int find_app_by_pid(pid_t pid) +{ + struct ltt_traceable_app *iter; + + pthread_mutex_lock(<t_traceable_app_list_mutex); + cds_list_for_each_entry(iter, <t_traceable_app_list.head, list) { + if (iter->pid == pid) { + pthread_mutex_unlock(<t_traceable_app_list_mutex); + /* Found */ + return 1; + } + } + pthread_mutex_unlock(<t_traceable_app_list_mutex); + + return 0; +} + +/* + * ust_create_trace + * + * Create an userspace trace using pid. + * This trace is then appended to the current session + * ust trace list. + */ +static int ust_create_trace(pid_t pid) +{ + int sock, ret; + struct ltt_ust_trace *trace; + + trace = malloc(sizeof(struct ltt_ust_trace)); + if (trace == NULL) { + perror("malloc"); + ret = -1; + goto error; + } + + /* Init */ + trace->pid = pid; + trace->shmid = 0; + + /* Connect to app using ustctl API */ + sock = connect_app(pid); + if (sock < 0) { + ret = LTTCOMM_NO_TRACEABLE; + goto error; + } + + ret = ustctl_create_trace(sock, "auto"); + if (ret < 0) { + ret = LTTCOMM_CREATE_FAIL; + goto error; + } + + /* Check if current session is valid */ + if (current_session) { + cds_list_add(&trace->list, ¤t_session->ust_traces); + } + +error: + return ret; +} + +/* + * get_list_apps + * + * List traceable user-space application and fill an + * array of pids. + */ +static void get_list_apps(pid_t *pids) +{ + int i = 0; + struct ltt_traceable_app *iter; + + /* Protected by a mutex here because the threads manage_client + * and manage_apps can access this list. + */ + pthread_mutex_lock(<t_traceable_app_list_mutex); + cds_list_for_each_entry(iter, <t_traceable_app_list.head, list) { + pids[i] = iter->pid; + i++; + } + pthread_mutex_unlock(<t_traceable_app_list_mutex); +} + +/* + * 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; + + /* Manage uuid */ + if (!uuid_is_null(lsm->session_id)) { + uuid_copy(llm->session_id, lsm->session_id); + } + + strncpy(llm->trace_name, lsm->trace_name, strlen(llm->trace_name)); + llm->trace_name[strlen(llm->trace_name) - 1] = '\0'; +} + +/* + * setup_data_buffer + * + * Setup the outgoing data buffer for the response + * data allocating the right amount of memory. + * + * Return total size of the buffer pointed by buf. + */ +static int setup_data_buffer(char **buf, size_t s_data, struct lttcomm_lttng_msg *llm) +{ + int ret = 0; + size_t buf_size; + + buf_size = sizeof(struct lttcomm_lttng_msg) + s_data; + *buf = malloc(buf_size); + if (*buf == NULL) { + perror("malloc"); + ret = -1; + goto error; + } + + /* Setup lttcomm_lttng_msg data and copy + * it to the newly allocated buffer. + */ + llm->size_payload = s_data; + memcpy(*buf, llm, sizeof(struct lttcomm_lttng_msg)); + + return buf_size; + +error: + return ret; +} + +/* + * process_client_msg + * + * This takes the lttcomm_session_msg struct and process the command requested + * by the client. It then creates response(s) and send it back to the + * given socket (sock). + * + * Return any error encountered or 0 for success. + */ +static int process_client_msg(int sock, struct lttcomm_session_msg *lsm) +{ + int ret; + int buf_size; + size_t header_size; + char *send_buf = NULL; + struct lttcomm_lttng_msg llm; + + /* Copy common data to identify the response + * on the lttng client side. + */ + copy_common_data(&llm, lsm); + + /* Check command that needs a session */ + if (lsm->cmd_type != LTTNG_CREATE_SESSION && + lsm->cmd_type != LTTNG_LIST_SESSIONS && + lsm->cmd_type != UST_LIST_APPS) + { + current_session = find_session_by_uuid(lsm->session_id); + if (current_session == NULL) { + ret = LTTCOMM_SELECT_SESS; + goto end; + } + } + + /* Default return code. + * In our world, everything is OK... right? ;) + */ + llm.ret_code = LTTCOMM_OK; + + header_size = sizeof(struct lttcomm_lttng_msg); + + /* Process by command type */ + switch (lsm->cmd_type) { + case LTTNG_CREATE_SESSION: + { + ret = create_session(lsm->session_name, &llm.session_id); + if (ret < 0) { + if (ret == -1) { + ret = LTTCOMM_EXIST_SESS; + } else { + ret = LTTCOMM_FATAL; + } + goto end; + } + + buf_size = setup_data_buffer(&send_buf, 0, &llm); + if (buf_size < 0) { + ret = LTTCOMM_FATAL; + goto end; + } + + break; + } + case LTTNG_DESTROY_SESSION: + { + ret = destroy_session(&lsm->session_id); + if (ret < 0) { + ret = LTTCOMM_NO_SESS; + } else { + ret = LTTCOMM_OK; + } + + /* No auxiliary data so only send the llm struct. */ + goto end; + } + case UST_CREATE_TRACE: + { + ret = ust_create_trace(lsm->pid); + if (ret < 0) { + ret = LTTCOMM_CREATE_FAIL; + goto end; + } + + /* No auxiliary data so only send the llm struct. */ + goto end; + } + case UST_LIST_APPS: + { + /* Stop right now if no apps */ + if (traceable_app_count == 0) { + ret = LTTCOMM_NO_APPS; + goto end; + } + + /* Setup data buffer and details for transmission */ + buf_size = setup_data_buffer(&send_buf, + sizeof(pid_t) * traceable_app_count, &llm); + if (buf_size < 0) { + ret = LTTCOMM_FATAL; + goto end; + } + + get_list_apps((pid_t *)(send_buf + header_size)); + + break; + } + case LTTNG_LIST_SESSIONS: + { + unsigned int session_count = get_session_count(); + /* Stop right now if no session */ + if (session_count == 0) { + ret = LTTCOMM_NO_SESS; + goto end; + } + + /* Setup data buffer and details for transmission */ + buf_size = setup_data_buffer(&send_buf, + (sizeof(struct lttng_session) * session_count), &llm); + if (buf_size < 0) { + ret = LTTCOMM_FATAL; + goto end; + } + + get_lttng_session((struct lttng_session *)(send_buf + header_size)); + + break; + } + default: + { + /* Undefined command */ + ret = LTTCOMM_UND; + goto end; + } + } + + ret = send_unix_sock(sock, send_buf, buf_size); + + if (send_buf != NULL) { + free(send_buf); + } + + return ret; + +end: + /* Notify client of error */ + llm.ret_code = ret; + llm.size_payload = 0; + send_unix_sock(sock, (void*) &llm, sizeof(llm)); + + return ret; +} + +/* + * usage function on stderr + */ +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"); +} + +/* + * daemon argument parsing + */ +static int parse_args(int argc, char **argv) +{ + int c; + + static struct option long_options[] = { + { "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' }, + { "quiet", 0, 0, 'q' }, + { NULL, 0, 0, 0 } + }; + + while (1) { + int option_index = 0; + c = getopt_long(argc, argv, "dhqVS" "a:c:g:s:", long_options, &option_index); + if (c == -1) { + break; + } + + switch (c) { + case 0: + fprintf(stderr, "option %s", long_options[option_index].name); + if (optarg) { + fprintf(stderr, " with arg %s\n", optarg); + } + break; + case 'c': + snprintf(client_unix_sock_path, PATH_MAX, "%s", optarg); + break; + case 'a': + snprintf(apps_unix_sock_path, PATH_MAX, "%s", optarg); + break; + case 'd': + opt_daemon = 1; + break; + case 'g': + opt_tracing_group = strdup(optarg); + break; + case 'h': + usage(); + exit(EXIT_FAILURE); + case 'V': + fprintf(stdout, "%s\n", VERSION); + exit(EXIT_SUCCESS); + case 'S': + opt_sig_parent = 1; + break; + case 'q': + opt_quiet = 1; + break; + default: + /* Unknown option or other error. + * Error is printed by getopt, just return */ + return -1; + } + } + + return 0; +} + +/* + * 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). + */ +static int init_daemon_socket() +{ + int ret = 0; + mode_t old_umask; + + old_umask = umask(0); + + /* Create client tool unix socket */ + client_socket = lttcomm_create_unix_sock(client_unix_sock_path); + if (client_socket < 0) { + ret = -1; + goto end; + } + + /* File permission MUST be 660 */ + ret = chmod(client_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP); + if (ret < 0) { + perror("chmod"); + goto end; + } + + /* Create the application unix socket */ + apps_socket = lttcomm_create_unix_sock(apps_unix_sock_path); + if (apps_socket < 0) { + ret = -1; + goto end; + } + + /* File permission MUST be 660 */ + ret = chmod(apps_unix_sock_path, S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH); + if (ret < 0) { + perror("chmod"); + goto end; + } + +end: + umask(old_umask); + return ret; +} + +/* + * check_existing_daemon + * + * Check if the global socket is available. + * If yes, error is returned. + */ +static int check_existing_daemon() +{ + int ret; + + ret = access(client_unix_sock_path, F_OK); + if (ret == 0) { + ret = access(apps_unix_sock_path, F_OK); + } + + return ret; +} + +/* + * get_home_dir + * + * Return pointer to home directory path using + * the env variable HOME. + * + * Default : /tmp + */ +static const char *get_home_dir(void) +{ + const char *home_path; + + if ((home_path = (const char *) getenv("HOME")) == NULL) { + home_path = default_home_dir; + } + + return home_path; +} + +/* + * set_socket_perms + * + * Set the tracing group gid onto the client socket. + */ +static int set_socket_perms(void) +{ + int ret; + struct group *grp; + + /* Decide which group name to use */ + (opt_tracing_group != NULL) ? + (grp = getgrnam(opt_tracing_group)) : + (grp = getgrnam(default_tracing_group)); + + if (grp == NULL) { + ERR("Missing tracing group. Aborting execution.\n"); + ret = -1; + goto end; + } + + ret = chown(client_unix_sock_path, 0, grp->gr_gid); + if (ret < 0) { + perror("chown"); + } + +end: + return ret; +} + +/* + * set_signal_handler + * + * Setup signal handler for : + * SIGINT, SIGTERM, SIGPIPE + */ +static int set_signal_handler(void) +{ + int ret = 0; + struct sigaction sa; + sigset_t sigset; + + if ((ret = sigemptyset(&sigset)) < 0) { + perror("sigemptyset"); + return ret; + } + + sa.sa_handler = sighandler; + sa.sa_mask = sigset; + sa.sa_flags = 0; + if ((ret = sigaction(SIGTERM, &sa, NULL)) < 0) { + perror("sigaction"); + return ret; + } + + if ((ret = sigaction(SIGINT, &sa, NULL)) < 0) { + perror("sigaction"); + return ret; + } + + if ((ret = sigaction(SIGPIPE, &sa, NULL)) < 0) { + perror("sigaction"); + return ret; + } + + return ret; +} + +/** + * sighandler + * + * Signal handler for the daemon + */ +static void sighandler(int sig) +{ + switch (sig) { + case SIGPIPE: + return; + case SIGINT: + case SIGTERM: + cleanup(); + break; + default: + break; + } + + exit(EXIT_SUCCESS); +} + +/* + * cleanup + * + * Cleanup the daemon on exit + */ +static void cleanup() +{ + /* */ + MSG("\n%c[%d;%dm*** assert failed *** ==> %c[%dm", 27,1,31,27,0); + MSG("%c[%d;%dmMatthew, BEET driven development works!%c[%dm",27,1,33,27,0); + /* */ + + unlink(client_unix_sock_path); + unlink(apps_unix_sock_path); +} + +/* + * main + */ +int main(int argc, char **argv) +{ + int i; + int ret = 0; + void *status; + pthread_t threads[2]; + + /* Parse arguments */ + progname = argv[0]; + if ((ret = parse_args(argc, argv) < 0)) { + goto error; + } + + /* Daemonize */ + if (opt_daemon) { + ret = daemon(0, 0); + if (ret < 0) { + perror("daemon"); + goto error; + } + } + + /* Check if daemon is UID = 0 */ + is_root = !getuid(); + + /* Set all sockets path */ + if (is_root) { + if (strlen(apps_unix_sock_path) == 0) { + (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)); + } + } else { + if (strlen(apps_unix_sock_path) == 0) { + (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())); + } + } + + /* See if daemon already exist. If any of the two + * socket needed by the daemon are present, this test fails + */ + 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. + */ + return EXIT_FAILURE; + } + + if (set_signal_handler() < 0) { + goto error; + } + + /* Setup the two needed unix socket */ + if (init_daemon_socket() < 0) { + goto error; + } + + /* Set credentials to socket */ + if (is_root && (set_socket_perms() < 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); + if (ret != 0) { + perror("pthread_create"); + goto error; + } + + /* Create thread to manage application socket */ + ret = pthread_create(&threads[1], NULL, thread_manage_apps, (void *) NULL); + if (ret != 0) { + perror("pthread_create"); + goto error; + } + + for (i = 0; i < 2; i++) { + ret = pthread_join(threads[i], &status); + if (ret != 0) { + perror("pthread_join"); + goto error; + } + } + } + + cleanup(); + return 0; + +error: + cleanup(); + + return EXIT_FAILURE; +} diff --git a/ltt-sessiond/session.c b/ltt-sessiond/session.c new file mode 100644 index 000000000..c6bc285cd --- /dev/null +++ b/ltt-sessiond/session.c @@ -0,0 +1,242 @@ +/* + * Copyright (C) 2011 - David Goulet + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +#define _GNU_SOURCE +#include +#include +#include +#include +#include +#include + +#include "lttngerr.h" +#include "session.h" + +/* Variables */ +static unsigned int session_count; + +/* Static internal function */ +static void add_session_list(struct ltt_session *ls); +static void del_session_list(struct ltt_session *ls); + +/* Init session's list */ +static struct ltt_session_list ltt_session_list = { + .head = CDS_LIST_HEAD_INIT(ltt_session_list.head), +}; + +/* + * get_session_count + * + * Return session_count + */ +unsigned int get_session_count(void) +{ + return session_count; +} + +/* + * add_session_list + * + * Add a ltt_session structure to the global list. + */ +static void add_session_list(struct ltt_session *ls) +{ + cds_list_add(&ls->list, <t_session_list.head); + session_count++; +} + +/* + * del_session_list + * + * Delete a ltt_session structure to the global list. + */ +static void del_session_list(struct ltt_session *ls) +{ + cds_list_del(&ls->list); + /* Sanity check */ + if (session_count != 0) { + session_count--; + } +} + +/* + * find_session_by_uuid + * + * Return a ltt_session structure ptr that matches the uuid. + */ +struct ltt_session *find_session_by_uuid(uuid_t session_id) +{ + int found = 0; + struct ltt_session *iter; + + /* Sanity check for NULL session_id */ + if (uuid_is_null(session_id)) { + goto end; + } + + cds_list_for_each_entry(iter, <t_session_list.head, list) { + if (uuid_compare(iter->uuid, session_id) == 0) { + found = 1; + break; + } + } + +end: + if (!found) { + iter = NULL; + } + return iter; +} + +/* + * find_session_by_name + * + * Return a ltt_session structure ptr that matches name. + * If no session found, NULL is returned. + */ +struct ltt_session *find_session_by_name(char *name) +{ + int found = 0; + struct ltt_session *iter; + + cds_list_for_each_entry(iter, <t_session_list.head, list) { + if (strncmp(iter->name, name, strlen(iter->name)) == 0) { + found = 1; + break; + } + } + + if (!found) { + iter = NULL; + } + + return iter; +} + +/* + * destroy_session + * + * Delete session from the global session list + * and free the memory. + * + * Return -1 if no session is found. + * On success, return 1; + */ +int destroy_session(uuid_t *uuid) +{ + int found = -1; + struct ltt_session *iter; + + cds_list_for_each_entry(iter, <t_session_list.head, list) { + if (uuid_compare(iter->uuid, *uuid) == 0) { + del_session_list(iter); + free(iter); + found = 1; + break; + } + } + + return found; +} + +/* + * create_session + * + * Create a brand new session and add it to the + * global session list. + */ +int create_session(char *name, uuid_t *session_id) +{ + struct ltt_session *new_session; + + new_session = find_session_by_name(name); + if (new_session != NULL) { + goto error; + } + + /* Allocate session data structure */ + new_session = malloc(sizeof(struct ltt_session)); + if (new_session == NULL) { + perror("malloc"); + goto error_mem; + } + + if (name != NULL) { + if (asprintf(&new_session->name, "%s", name) < 0) { + goto error_mem; + } + } else { + /* Generate session name based on the session count */ + if (asprintf(&new_session->name, "%s%d", "lttng-", session_count) < 0) { + goto error_mem; + } + } + + /* UUID generation */ + uuid_generate(new_session->uuid); + uuid_copy(*session_id, new_session->uuid); + + /* Set consumer (identifier) to 0. This means that there is + * NO consumer attach to that session yet. + */ + new_session->ust_consumer = 0; + new_session->lttng_consumer = 0; + + /* Init list */ + CDS_INIT_LIST_HEAD(&new_session->ust_traces); + CDS_INIT_LIST_HEAD(&new_session->lttng_traces); + + /* Add new session to the global session list */ + add_session_list(new_session); + + return 0; + +error: + return -1; + +error_mem: + return -ENOMEM; +} + +/* + * get_lttng_session + * + * Iterate over the global session list and + * fill the lttng_session array. + */ +void get_lttng_session(struct lttng_session *lt) +{ + int i = 0; + struct ltt_session *iter; + struct lttng_session lsess; + + /* Iterate over session list and append data after + * the control struct in the buffer. + */ + cds_list_for_each_entry(iter, <t_session_list.head, list) { + /* Copy name and uuid */ + uuid_unparse(iter->uuid, lsess.uuid); + strncpy(lsess.name, iter->name, sizeof(lsess.name)); + lsess.name[sizeof(lsess.name) - 1] = '\0'; + memcpy(<[i], &lsess, sizeof(lsess)); + i++; + /* Reset struct for next pass */ + memset(&lsess, 0, sizeof(lsess)); + } +} + diff --git a/ltt-sessiond/session.h b/ltt-sessiond/session.h new file mode 100644 index 000000000..5bfe16ac0 --- /dev/null +++ b/ltt-sessiond/session.h @@ -0,0 +1,48 @@ +/* + * Copyright (C) 2011 - David Goulet + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version 2 + * of the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + */ + +#ifndef _LTT_SESSION_H +#define _LTT_SESSION_H + +/* Global session list */ +struct ltt_session_list { + struct cds_list_head head; +}; + +/* ltt-session - This data structure contains information needed + * to identify a tracing session for both LTTng and UST. + */ +struct ltt_session { + char *name; + struct cds_list_head list; + uuid_t uuid; + struct cds_list_head ust_traces; + struct cds_list_head lttng_traces; + pid_t ust_consumer; + pid_t lttng_consumer; +}; + +/* Prototypes */ +int create_session(char *name, uuid_t *session_id); +int destroy_session(uuid_t *uuid); +void get_lttng_session(struct lttng_session *lt); +struct ltt_session *find_session_by_uuid(uuid_t session_id); +struct ltt_session *find_session_by_name(char *name); +unsigned int get_session_count(void); + +#endif /* _LTT_SESSION_H */