-/*
- * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
- *
- * 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 <fcntl.h>
-#include <getopt.h>
-#include <grp.h>
-#include <limits.h>
-#include <pthread.h>
-#include <signal.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/ipc.h>
-#include <sys/shm.h>
-#include <sys/socket.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-#include <unistd.h>
-
-#include <urcu/list.h> /* URCU list library (-lurcu) */
-#include <ust/ustctl.h> /* UST control lib (-lust) */
-#include <lttng/liblttngctl.h>
-
-#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()
-{
- /* <fun> */
- 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);
- /* </fun> */
-
- 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;
-}
projects / lttng-tools.git / commitdiff
