X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=ltt-sessiond%2Fmain.c;h=c50bfd88c5d7538638081c3d7f44511848724d8a;hp=90aea69fc2e6e4a15266dca3fc35124448179869;hb=5461b305aef403f7f2e48c977c188b5526746c6e;hpb=6abb15de23fcd1413963aef20f9f2c243f1bf749 diff --git a/ltt-sessiond/main.c b/ltt-sessiond/main.c index 90aea69fc..c50bfd88c 100644 --- a/ltt-sessiond/main.c +++ b/ltt-sessiond/main.c @@ -44,6 +44,13 @@ #include "trace.h" #include "traceable-app.h" +/* + * TODO: + * teardown: signal SIGTERM handler -> write into pipe. Threads waits + * with epoll on pipe and on other pipes/sockets for commands. Main + * simply waits on pthread join. + */ + /* Const values */ const char default_home_dir[] = DEFAULT_HOME_DIR; const char default_tracing_group[] = DEFAULT_TRACING_GROUP; @@ -52,19 +59,19 @@ const char default_global_apps_pipe[] = DEFAULT_GLOBAL_APPS_PIPE; /* Static functions */ static int check_existing_daemon(void); -static int connect_app(pid_t pid); +static int ust_connect_app(pid_t pid); static int init_daemon_socket(void); static int notify_apps(const char* name); -static int process_client_msg(int sock, struct lttcomm_session_msg*); +static int process_client_msg(struct command_ctx *cmd_ctx); static int send_unix_sock(int sock, void *buf, size_t len); static int set_signal_handler(void); static int set_permissions(void); -static int setup_data_buffer(char **buf, size_t size, struct lttcomm_lttng_header *llh); +static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size); static int create_lttng_rundir(void); static int set_kconsumerd_sockets(void); static void cleanup(void); -static void copy_common_data(struct lttcomm_lttng_header *llh, struct lttcomm_session_msg *lsm); static void sighandler(int sig); +static void clean_command_ctx(struct command_ctx *cmd_ctx); static void *thread_manage_clients(void *data); static void *thread_manage_apps(void *data); @@ -89,8 +96,6 @@ static int client_sock; static int apps_sock; static int kconsumerd_err_sock; -static struct ltt_session *current_session; - /* * thread_manage_kconsumerd * @@ -135,6 +140,9 @@ static void *thread_manage_apps(void *data) int sock, ret; /* TODO: Something more elegant is needed but fine for now */ + /* FIXME: change all types to either uint8_t, uint32_t, uint64_t + * for 32-bit vs 64-bit compat processes. */ + /* replicate in ust with version number */ struct { int reg; /* 1:register, 0:unregister */ pid_t pid; @@ -143,14 +151,14 @@ static void *thread_manage_apps(void *data) DBG("[thread] Manage apps started"); - /* Notify all applications to register */ - notify_apps(default_global_apps_pipe); - ret = lttcomm_listen_unix_sock(apps_sock); if (ret < 0) { goto error; } + /* Notify all applications to register */ + notify_apps(default_global_apps_pipe); + while (1) { /* Blocking call, waiting for transmission */ sock = lttcomm_accept_unix_sock(apps_sock); @@ -197,7 +205,7 @@ error: static void *thread_manage_clients(void *data) { int sock, ret; - struct lttcomm_session_msg lsm; + struct command_ctx *cmd_ctx; DBG("[thread] Manage client started"); @@ -215,31 +223,53 @@ static void *thread_manage_clients(void *data) while (1) { /* Blocking call, waiting for transmission */ + DBG("Accepting client command ..."); sock = lttcomm_accept_unix_sock(client_sock); if (sock < 0) { goto error; } + /* Allocate context command to process the client request */ + cmd_ctx = malloc(sizeof(struct command_ctx)); + + /* Allocate data buffer for reception */ + cmd_ctx->lsm = malloc(sizeof(struct lttcomm_session_msg)); + cmd_ctx->llm = NULL; + cmd_ctx->session = NULL; + /* * Data is received from the lttng client. The struct - * lttcomm_session_msg (lsm) contains the command and data - * request of the client. + * lttcomm_session_msg (lsm) contains the command and data request of + * the client. */ - ret = lttcomm_recv_unix_sock(sock, &lsm, sizeof(lsm)); + DBG("Receiving data from client ..."); + ret = lttcomm_recv_unix_sock(sock, cmd_ctx->lsm, sizeof(struct lttcomm_session_msg)); 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_header to - * send out so process_client_msg do both jobs. + /* + * This function dispatch the work to the kernel or userspace tracer + * libs and fill the lttcomm_lttng_msg data structure of all the needed + * informations for the client. The command context struct contains + * everything this function may needs. */ - ret = process_client_msg(sock, &lsm); + ret = process_client_msg(cmd_ctx); if (ret < 0) { + /* TODO: Inform client somehow of the fatal error. At this point, + * ret < 0 means that a malloc failed (ENOMEM). */ /* Error detected but still accept command */ + clean_command_ctx(cmd_ctx); continue; } + + DBG("Sending response to client (size: %d)", cmd_ctx->lttng_msg_size); + ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size); + if (ret < 0) { + ERR("Failed to send data back to client"); + } + + clean_command_ctx(cmd_ctx); } error: @@ -264,7 +294,27 @@ static int send_unix_sock(int sock, void *buf, size_t len) } /* - * connect_app + * clean_command_ctx + * + * Free memory of a command context structure. + */ +static void clean_command_ctx(struct command_ctx *cmd_ctx) +{ + DBG("Clean command context structure %p", cmd_ctx); + if (cmd_ctx) { + if (cmd_ctx->llm) { + free(cmd_ctx->llm); + } + if (cmd_ctx->lsm) { + free(cmd_ctx->lsm); + } + free(cmd_ctx); + cmd_ctx = NULL; + } +} + +/* + * ust_connect_app * * Return a socket connected to the libust communication socket * of the application identified by the pid. @@ -272,7 +322,7 @@ static int send_unix_sock(int sock, void *buf, size_t len) * If the pid is not found in the traceable list, * return -1 to indicate error. */ -static int connect_app(pid_t pid) +static int ust_connect_app(pid_t pid) { int sock; struct ltt_traceable_app *lta; @@ -327,175 +377,45 @@ error: } /* - * ust_create_trace + * setup_lttng_msg * - * 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; - - DBG("Creating trace for pid %d", pid); - - trace = malloc(sizeof(struct ltt_ust_trace)); - if (trace == NULL) { - perror("malloc"); - ret = -1; - goto error; - } - - /* Init */ - trace->pid = pid; - trace->shmid = 0; - /* NOTE: to be removed. Trace name will no longer be - * required for LTTng userspace tracer. For now, we set it - * to 'auto' for API compliance. - */ - snprintf(trace->name, 5, "auto"); - - /* Connect to app using ustctl API */ - sock = connect_app(pid); - if (sock < 0) { - ret = LTTCOMM_NO_TRACEABLE; - goto error; - } - - ret = ustctl_create_trace(sock, trace->name); - 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); - current_session->ust_trace_count++; - } - -error: - return ret; -} - -/* - * ust_start_trace + * Setup the outgoing data buffer for the response (llm) by allocating the + * right amount of memory and copying the original information from the lsm + * structure. * - * Start a trace. This trace, identified by the pid, must be - * in the current session ust_traces list. - */ -static int ust_start_trace(pid_t pid) -{ - int sock, ret; - struct ltt_ust_trace *trace; - - DBG("Starting trace for pid %d", pid); - - trace = find_session_ust_trace_by_pid(current_session, pid); - if (trace == NULL) { - ret = LTTCOMM_NO_TRACE; - goto error; - } - - /* Connect to app using ustctl API */ - sock = connect_app(pid); - if (sock < 0) { - ret = LTTCOMM_NO_TRACEABLE; - goto error; - } - - ret = ustctl_start_trace(sock, "auto"); - if (ret < 0) { - ret = LTTCOMM_START_FAIL; - goto error; - } - -error: - return ret; -} - -/* - * ust_stop_trace - * - * Stop a trace. This trace, identified by the pid, must be - * in the current session ust_traces list. + * Return total size of the buffer pointed by buf. */ -static int ust_stop_trace(pid_t pid) +static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size) { - int sock, ret; - struct ltt_ust_trace *trace; + int ret, buf_size, trace_name_size; - DBG("Stopping trace for pid %d", pid); + /* + * Check for the trace_name. If defined, it's part of the payload data of + * the llm structure. + */ + trace_name_size = strlen(cmd_ctx->lsm->trace_name); + buf_size = trace_name_size + size; - trace = find_session_ust_trace_by_pid(current_session, pid); - if (trace == NULL) { - ret = LTTCOMM_NO_TRACE; + cmd_ctx->llm = malloc(sizeof(struct lttcomm_lttng_msg) + buf_size); + if (cmd_ctx->llm == NULL) { + perror("malloc"); + ret = -ENOMEM; goto error; } - /* Connect to app using ustctl API */ - sock = connect_app(pid); - if (sock < 0) { - ret = LTTCOMM_NO_TRACEABLE; - goto error; + /* Copy common data */ + cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type; + cmd_ctx->llm->pid = cmd_ctx->lsm->pid; + if (!uuid_is_null(cmd_ctx->lsm->session_uuid)) { + uuid_copy(cmd_ctx->llm->session_uuid, cmd_ctx->lsm->session_uuid); } - ret = ustctl_stop_trace(sock, trace->name); - if (ret < 0) { - ret = LTTCOMM_STOP_FAIL; - goto error; - } - -error: - return ret; -} - -/* - * copy_common_data - * - * Copy common data between lttcomm_lttng_header and lttcomm_session_msg - */ -static void copy_common_data(struct lttcomm_lttng_header *llh, struct lttcomm_session_msg *lsm) -{ - llh->cmd_type = lsm->cmd_type; - llh->pid = lsm->pid; - - /* Manage uuid */ - if (!uuid_is_null(lsm->session_id)) { - uuid_copy(llh->session_id, lsm->session_id); - } - - strncpy(llh->trace_name, lsm->trace_name, strlen(llh->trace_name)); - llh->trace_name[strlen(llh->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_header *llh) -{ - int ret = 0; - size_t buf_size; - - buf_size = sizeof(struct lttcomm_lttng_header) + s_data; - *buf = malloc(buf_size); - if (*buf == NULL) { - perror("malloc"); - ret = -1; - goto error; - } + cmd_ctx->llm->trace_name_offset = trace_name_size; + cmd_ctx->llm->data_size = size; + cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size; - /* Setup lttcomm_lttng_header data and copy - * it to the newly allocated buffer. - */ - llh->payload_size = s_data; - memcpy(*buf, llh, sizeof(struct lttcomm_lttng_header)); + /* Copy trace name to the llm structure. Begining of the payload. */ + memcpy(cmd_ctx->llm->payload, cmd_ctx->lsm->trace_name, trace_name_size); return buf_size; @@ -506,192 +426,217 @@ error: /* * 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). + * Process the command requested by the lttng client within the command + * context structure. This function make sure that the return structure (llm) + * is set and ready for transmission before returning. * * Return any error encountered or 0 for success. */ -static int process_client_msg(int sock, struct lttcomm_session_msg *lsm) +static int process_client_msg(struct command_ctx *cmd_ctx) { int ret; - int buf_size; - size_t header_size; - char *send_buf = NULL; - struct lttcomm_lttng_header llh; - DBG("Processing client message"); - - /* Copy common data to identify the response - * on the lttng client side. - */ - copy_common_data(&llh, lsm); + DBG("Processing client command %d", cmd_ctx->lsm->cmd_type); /* 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) { + switch (cmd_ctx->lsm->cmd_type) { + case LTTNG_CREATE_SESSION: + case LTTNG_LIST_SESSIONS: + case UST_LIST_APPS: + break; + default: + cmd_ctx->session = find_session_by_uuid(cmd_ctx->lsm->session_uuid); + if (cmd_ctx->session == NULL) { ret = LTTCOMM_SELECT_SESS; - goto end; + goto error; } + break; } - /* Default return code. - * In our world, everything is OK... right? ;) - */ - llh.ret_code = LTTCOMM_OK; - - header_size = sizeof(struct lttcomm_lttng_header); + /* Connect to ust apps if available pid */ + if (cmd_ctx->lsm->pid > 0) { + /* Connect to app using ustctl API */ + cmd_ctx->ust_sock = ust_connect_app(cmd_ctx->lsm->pid); + if (cmd_ctx->ust_sock < 0) { + ret = LTTCOMM_NO_TRACEABLE; + goto error; + } + } /* Process by command type */ - switch (lsm->cmd_type) { - case LTTNG_CREATE_SESSION: - { - ret = create_session(lsm->session_name, &llh.session_id); - if (ret < 0) { - if (ret == -1) { - ret = LTTCOMM_EXIST_SESS; - } else { - ret = LTTCOMM_FATAL; - } - goto end; - } + switch (cmd_ctx->lsm->cmd_type) { + case LTTNG_CREATE_SESSION: + { + /* Setup lttng message with no payload */ + ret = setup_lttng_msg(cmd_ctx, 0); + if (ret < 0) { + goto setup_error; + } - buf_size = setup_data_buffer(&send_buf, 0, &llh); - if (buf_size < 0) { + ret = create_session(cmd_ctx->lsm->session_name, &cmd_ctx->llm->session_uuid); + if (ret < 0) { + if (ret == -1) { + ret = LTTCOMM_EXIST_SESS; + } else { ret = LTTCOMM_FATAL; - goto end; } - - break; + goto error; } - 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 llh struct. */ - goto end; + ret = LTTCOMM_OK; + break; + } + case LTTNG_DESTROY_SESSION: + { + /* Setup lttng message with no payload */ + ret = setup_lttng_msg(cmd_ctx, 0); + if (ret < 0) { + goto setup_error; } - case LTTNG_LIST_TRACES: - { - unsigned int trace_count = get_trace_count_per_session(current_session); - if (trace_count == 0) { - ret = LTTCOMM_NO_TRACE; - goto end; - } + ret = destroy_session(&cmd_ctx->lsm->session_uuid); + if (ret < 0) { + ret = LTTCOMM_NO_SESS; + goto error; + } - buf_size = setup_data_buffer(&send_buf, - sizeof(struct lttng_trace) * trace_count, &llh); - if (buf_size < 0) { - ret = LTTCOMM_FATAL; - goto end; - } + ret = LTTCOMM_OK; + break; + } + case LTTNG_LIST_TRACES: + { + unsigned int trace_count; - get_traces_per_session(current_session, (struct lttng_trace *)(send_buf + header_size)); - break; + trace_count = get_trace_count_per_session(cmd_ctx->session); + if (trace_count == 0) { + ret = LTTCOMM_NO_TRACE; + goto error; } - case UST_CREATE_TRACE: - { - ret = ust_create_trace(lsm->pid); - if (ret < 0) { - /* If -1 is returned from ust_create_trace, malloc - * failed so it's pretty much a fatal error. - */ - ret = LTTCOMM_FATAL; - goto end; - } - /* No auxiliary data so only send the llh struct. */ - goto end; + ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_trace) * trace_count); + if (ret < 0) { + goto setup_error; } - case UST_LIST_APPS: - { - unsigned int app_count = get_app_count(); - /* Stop right now if no apps */ - if (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) * app_count, &llh); - if (buf_size < 0) { - ret = LTTCOMM_FATAL; - goto end; - } + get_traces_per_session(cmd_ctx->session, + (struct lttng_trace *)(cmd_ctx->llm->payload)); - get_app_list_pids((pid_t *)(send_buf + header_size)); + ret = LTTCOMM_OK; + break; + } + case UST_CREATE_TRACE: + { + /* Setup lttng message with no payload */ + ret = setup_lttng_msg(cmd_ctx, 0); + if (ret < 0) { + goto setup_error; + } - break; + ret = ust_create_trace(cmd_ctx); + if (ret < 0) { + goto setup_error; } - case UST_START_TRACE: - { - ret = ust_start_trace(lsm->pid); + break; + } + case UST_LIST_APPS: + { + unsigned int app_count; - /* No auxiliary data so only send the llh struct. */ - goto end; + app_count = get_app_count(); + DBG("Traceable application count : %d", app_count); + if (app_count == 0) { + ret = LTTCOMM_NO_APPS; + goto error; } - case UST_STOP_TRACE: - { - ret = ust_stop_trace(lsm->pid); - /* No auxiliary data so only send the llh struct. */ - goto end; + ret = setup_lttng_msg(cmd_ctx, sizeof(pid_t) * app_count); + if (ret < 0) { + goto setup_error; } - 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), &llh); - if (buf_size < 0) { - ret = LTTCOMM_FATAL; - goto end; - } + get_app_list_pids((pid_t *)(cmd_ctx->llm->payload)); - get_lttng_session((struct lttng_session *)(send_buf + header_size)); + ret = LTTCOMM_OK; + break; + } + case UST_START_TRACE: + { + /* Setup lttng message with no payload */ + ret = setup_lttng_msg(cmd_ctx, 0); + if (ret < 0) { + goto setup_error; + } - break; + ret = ust_start_trace(cmd_ctx); + if (ret < 0) { + goto setup_error; } - default: - { - /* Undefined command */ - ret = LTTCOMM_UND; - goto end; + break; + } + case UST_STOP_TRACE: + { + /* Setup lttng message with no payload */ + ret = setup_lttng_msg(cmd_ctx, 0); + if (ret < 0) { + goto setup_error; } + + ret = ust_stop_trace(cmd_ctx); + if (ret < 0) { + goto setup_error; + } + break; } + case LTTNG_LIST_SESSIONS: + { + unsigned int session_count; - ret = send_unix_sock(sock, send_buf, buf_size); + session_count = get_session_count(); + if (session_count == 0) { + ret = LTTCOMM_NO_SESS; + goto error; + } - if (send_buf != NULL) { - free(send_buf); + ret = setup_lttng_msg(cmd_ctx, sizeof(struct lttng_session) * session_count); + if (ret < 0) { + goto setup_error; + } + + get_lttng_session((struct lttng_session *)(cmd_ctx->llm->payload)); + + ret = LTTCOMM_OK; + break; } + default: + /* Undefined command */ + ret = setup_lttng_msg(cmd_ctx, 0); + if (ret < 0) { + goto setup_error; + } + + ret = LTTCOMM_UND; + break; + } + + /* Set return code */ + cmd_ctx->llm->ret_code = ret; return ret; -end: +error: DBG("Return code to client %d", ret); + + if (cmd_ctx->llm == NULL) { + DBG("Missing llm structure. Allocating one."); + ret = setup_lttng_msg(cmd_ctx, 0); + if (ret < 0) { + goto setup_error; + } + } /* Notify client of error */ - llh.ret_code = ret; - llh.payload_size = 0; - send_unix_sock(sock, (void*) &llh, sizeof(llh)); + cmd_ctx->llm->ret_code = ret; +setup_error: return ret; } @@ -884,7 +829,10 @@ static const char *get_home_dir(void) /* * set_permissions * - * Set the tracing group gid onto the client socket. + * Set the tracing group gid onto the client socket. + * + * Race window between mkdir and chown is OK because we are going from + * less permissive (root.root) to more permissive (root.tracing). */ static int set_permissions(void) { @@ -1162,7 +1110,7 @@ int main(int argc, char **argv) /* We do not goto error because we must not * cleanup() because a daemon is already running. */ - return EXIT_FAILURE; + exit(EXIT_FAILURE); } if (set_signal_handler() < 0) { @@ -1209,10 +1157,9 @@ int main(int argc, char **argv) } cleanup(); - return 0; + exit(EXIT_SUCCESS); error: cleanup(); - - return EXIT_FAILURE; + exit(EXIT_FAILURE); }