X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Flib%2Flttng-ctl%2Flttng-ctl.cpp;fp=src%2Flib%2Flttng-ctl%2Flttng-ctl.cpp;h=3622987183c5db8c4bdf8e0f48b70b7bd63b5366;hp=0000000000000000000000000000000000000000;hb=4bd69c5f1161cd065f487da0f4c1aa03a73c47e4;hpb=657d1bf105996bf8f6e13af697fb1112afa61b28 diff --git a/src/lib/lttng-ctl/lttng-ctl.cpp b/src/lib/lttng-ctl/lttng-ctl.cpp new file mode 100644 index 000000000..362298718 --- /dev/null +++ b/src/lib/lttng-ctl/lttng-ctl.cpp @@ -0,0 +1,3519 @@ +/* + * lttng-ctl.c + * + * Linux Trace Toolkit Control Library + * + * Copyright (C) 2011 David Goulet + * Copyright (C) 2016 Jérémie Galarneau + * + * SPDX-License-Identifier: LGPL-2.1-only + * + */ + +#define _LGPL_SOURCE +#include +#include +#include +#include +#include + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include "lttng-ctl-helper.h" +#include +#include +#include + +#define COPY_DOMAIN_PACKED(dst, src) \ +do { \ + struct lttng_domain _tmp_domain; \ + \ + lttng_ctl_copy_lttng_domain(&_tmp_domain, &src); \ + dst = _tmp_domain; \ +} while (0) + +/* Socket to session daemon for communication */ +static int sessiond_socket = -1; +static char sessiond_sock_path[PATH_MAX]; + +/* Variables */ +static char *tracing_group; +static int connected; + +/* Global */ + +/* + * Those two variables are used by error.h to silent or control the verbosity of + * error message. They are global to the library so application linking with it + * are able to compile correctly and also control verbosity of the library. + */ +LTTNG_EXPORT int lttng_opt_quiet; +LTTNG_EXPORT int lttng_opt_verbose; +LTTNG_EXPORT int lttng_opt_mi; + +/* + * Copy domain to lttcomm_session_msg domain. + * + * If domain is unknown, default domain will be the kernel. + */ +void lttng_ctl_copy_lttng_domain(struct lttng_domain *dst, + struct lttng_domain *src) +{ + if (src && dst) { + switch (src->type) { + case LTTNG_DOMAIN_KERNEL: + case LTTNG_DOMAIN_UST: + case LTTNG_DOMAIN_JUL: + case LTTNG_DOMAIN_LOG4J: + case LTTNG_DOMAIN_PYTHON: + memcpy(dst, src, sizeof(struct lttng_domain)); + break; + default: + memset(dst, 0, sizeof(struct lttng_domain)); + break; + } + } +} + +/* + * Send lttcomm_session_msg to the session daemon. + * + * On success, returns the number of bytes sent (>=0) + * On error, returns -1 + */ +static int send_session_msg(struct lttcomm_session_msg *lsm) +{ + int ret; + + if (!connected) { + ret = -LTTNG_ERR_NO_SESSIOND; + goto end; + } + + DBG("LSM cmd type: '%s' (%d)", lttcomm_sessiond_command_str((lttcomm_sessiond_command) lsm->cmd_type), + lsm->cmd_type); + + ret = lttcomm_send_creds_unix_sock(sessiond_socket, lsm, + sizeof(struct lttcomm_session_msg)); + if (ret < 0) { + ret = -LTTNG_ERR_FATAL; + } + +end: + return ret; +} + +/* + * Send var len data to the session daemon. + * + * On success, returns the number of bytes sent (>=0) + * On error, returns -1 + */ +static int send_session_varlen(const void *data, size_t len) +{ + int ret; + + if (!connected) { + ret = -LTTNG_ERR_NO_SESSIOND; + goto end; + } + + if (!data || !len) { + ret = 0; + goto end; + } + + ret = lttcomm_send_unix_sock(sessiond_socket, data, len); + if (ret < 0) { + ret = -LTTNG_ERR_FATAL; + } + +end: + return ret; +} + +/* + * Send file descriptors to the session daemon. + * + * On success, returns the number of bytes sent (>=0) + * On error, returns -1 + */ +static int send_session_fds(const int *fds, size_t nb_fd) +{ + int ret; + + if (!connected) { + ret = -LTTNG_ERR_NO_SESSIOND; + goto end; + } + + if (!fds || !nb_fd) { + ret = 0; + goto end; + } + + ret = lttcomm_send_fds_unix_sock(sessiond_socket, fds, nb_fd); + if (ret < 0) { + ret = -LTTNG_ERR_FATAL; + } + +end: + return ret; +} + +/* + * Receive data from the sessiond socket. + * + * On success, returns the number of bytes received (>=0) + * On error, returns a negative lttng_error_code. + */ +static int recv_data_sessiond(void *buf, size_t len) +{ + int ret; + + LTTNG_ASSERT(len > 0); + + if (!connected) { + ret = -LTTNG_ERR_NO_SESSIOND; + goto end; + } + + ret = lttcomm_recv_unix_sock(sessiond_socket, buf, len); + if (ret < 0) { + ret = -LTTNG_ERR_FATAL; + } else if (ret == 0) { + ret = -LTTNG_ERR_NO_SESSIOND; + } + +end: + return ret; +} + +/* + * Receive a payload from the session daemon by appending to an existing + * payload. + * On success, returns the number of bytes received (>=0) + * On error, returns a negative lttng_error_code. + */ +static int recv_payload_sessiond(struct lttng_payload *payload, size_t len) +{ + int ret; + const size_t original_payload_size = payload->buffer.size; + + ret = lttng_dynamic_buffer_set_size( + &payload->buffer, payload->buffer.size + len); + if (ret) { + ret = -LTTNG_ERR_NOMEM; + goto end; + } + + ret = recv_data_sessiond( + payload->buffer.data + original_payload_size, len); +end: + return ret; +} + +/* + * Check if we are in the specified group. + * + * If yes return 1, else return -1. + */ +int lttng_check_tracing_group(void) +{ + gid_t *grp_list, tracing_gid; + int grp_list_size, grp_id, i; + int ret = -1; + const char *grp_name = tracing_group; + + /* Get GID of group 'tracing' */ + if (utils_get_group_id(grp_name, false, &tracing_gid)) { + /* If grp_tracing is NULL, the group does not exist. */ + goto end; + } + + /* Get number of supplementary group IDs */ + grp_list_size = getgroups(0, NULL); + if (grp_list_size < 0) { + PERROR("getgroups"); + goto end; + } + + /* Alloc group list of the right size */ + grp_list = (gid_t *) zmalloc(grp_list_size * sizeof(gid_t)); + if (!grp_list) { + PERROR("malloc"); + goto end; + } + grp_id = getgroups(grp_list_size, grp_list); + if (grp_id < 0) { + PERROR("getgroups"); + goto free_list; + } + + for (i = 0; i < grp_list_size; i++) { + if (grp_list[i] == tracing_gid) { + ret = 1; + break; + } + } + +free_list: + free(grp_list); + +end: + return ret; +} + +static int check_enough_available_memory(size_t num_bytes_requested_per_cpu) +{ + int ret; + long num_cpu; + size_t best_mem_info; + size_t num_bytes_requested_total; + + /* + * Get the number of CPU currently online to compute the amount of + * memory needed to create a buffer for every CPU. + */ + num_cpu = sysconf(_SC_NPROCESSORS_ONLN); + if (num_cpu == -1) { + goto error; + } + + num_bytes_requested_total = num_bytes_requested_per_cpu * num_cpu; + + /* + * Try to get the `MemAvail` field of `/proc/meminfo`. This is the most + * reliable estimate we can get but it is only exposed by the kernel + * since 3.14. (See Linux kernel commit: + * 34e431b0ae398fc54ea69ff85ec700722c9da773) + */ + ret = utils_get_memory_available(&best_mem_info); + if (ret >= 0) { + goto success; + } + + /* + * As a backup plan, use `MemTotal` field of `/proc/meminfo`. This + * is a sanity check for obvious user error. + */ + ret = utils_get_memory_total(&best_mem_info); + if (ret >= 0) { + goto success; + } + +error: + return -1; +success: + return best_mem_info >= num_bytes_requested_total; +} + +/* + * Try connect to session daemon with sock_path. + * + * Return 0 on success, else -1 + */ +static int try_connect_sessiond(const char *sock_path) +{ + int ret; + + /* If socket exist, we check if the daemon listens for connect. */ + ret = access(sock_path, F_OK); + if (ret < 0) { + /* Not alive */ + goto error; + } + + ret = lttcomm_connect_unix_sock(sock_path); + if (ret < 0) { + /* Not alive. */ + goto error; + } + + ret = lttcomm_close_unix_sock(ret); + if (ret < 0) { + PERROR("lttcomm_close_unix_sock"); + } + + return 0; + +error: + return -1; +} + +/* + * Set sessiond socket path by putting it in the global sessiond_sock_path + * variable. + * + * Returns 0 on success, negative value on failure (the sessiond socket path + * is somehow too long or ENOMEM). + */ +static int set_session_daemon_path(void) +{ + int in_tgroup = 0; /* In tracing group. */ + uid_t uid; + + uid = getuid(); + + if (uid != 0) { + /* Are we in the tracing group ? */ + in_tgroup = lttng_check_tracing_group(); + } + + if ((uid == 0) || in_tgroup == 1) { + const int ret = lttng_strncpy(sessiond_sock_path, + DEFAULT_GLOBAL_CLIENT_UNIX_SOCK, + sizeof(sessiond_sock_path)); + + if (ret) { + goto error; + } + } + + if (uid != 0) { + int ret; + + if (in_tgroup) { + /* Tracing group. */ + ret = try_connect_sessiond(sessiond_sock_path); + if (ret >= 0) { + goto end; + } + /* Global session daemon not available... */ + } + /* ...or not in tracing group (and not root), default */ + + /* + * With GNU C < 2.1, snprintf returns -1 if the target buffer + * is too small; + * With GNU C >= 2.1, snprintf returns the required size + * (excluding closing null) + */ + ret = snprintf(sessiond_sock_path, sizeof(sessiond_sock_path), + DEFAULT_HOME_CLIENT_UNIX_SOCK, utils_get_home_dir()); + if ((ret < 0) || (ret >= sizeof(sessiond_sock_path))) { + goto error; + } + } +end: + return 0; + +error: + return -1; +} + +/* + * Connect to the LTTng session daemon. + * + * On success, return the socket's file descriptor. On error, return -1. + */ +int connect_sessiond(void) +{ + int ret; + + ret = set_session_daemon_path(); + if (ret < 0) { + goto error; + } + + /* Connect to the sesssion daemon. */ + ret = lttcomm_connect_unix_sock(sessiond_sock_path); + if (ret < 0) { + goto error; + } + + return ret; + +error: + return -1; +} + +static void reset_global_sessiond_connection_state(void) +{ + sessiond_socket = -1; + connected = 0; +} + +/* + * Clean disconnect from the session daemon. + * + * On success, return 0. On error, return -1. + */ +static int disconnect_sessiond(void) +{ + int ret = 0; + + if (connected) { + ret = lttcomm_close_unix_sock(sessiond_socket); + reset_global_sessiond_connection_state(); + } + + return ret; +} + +static int recv_sessiond_optional_data(size_t len, void **user_buf, + size_t *user_len) +{ + int ret = 0; + void *buf = NULL; + + if (len) { + if (!user_len) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + buf = zmalloc(len); + if (!buf) { + ret = -ENOMEM; + goto end; + } + + ret = recv_data_sessiond(buf, len); + if (ret < 0) { + goto end; + } + + if (!user_buf) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + /* Move ownership of command header buffer to user. */ + *user_buf = buf; + buf = NULL; + *user_len = len; + } else { + /* No command header. */ + if (user_len) { + *user_len = 0; + } + + if (user_buf) { + *user_buf = NULL; + } + } + +end: + free(buf); + return ret; +} + +/* + * Ask the session daemon a specific command and put the data into buf. + * Takes extra var. len. data and file descriptors as input to send to the + * session daemon. + * + * Return size of data (only payload, not header) or a negative error code. + */ +int lttng_ctl_ask_sessiond_fds_varlen(struct lttcomm_session_msg *lsm, + const int *fds, size_t nb_fd, const void *vardata, + size_t vardata_len, void **user_payload_buf, + void **user_cmd_header_buf, size_t *user_cmd_header_len) +{ + int ret; + size_t payload_len; + struct lttcomm_lttng_msg llm; + + ret = connect_sessiond(); + if (ret < 0) { + ret = -LTTNG_ERR_NO_SESSIOND; + goto end; + } else { + sessiond_socket = ret; + connected = 1; + } + + ret = send_session_msg(lsm); + if (ret < 0) { + /* Ret value is a valid lttng error code. */ + goto end; + } + /* Send var len data */ + ret = send_session_varlen(vardata, vardata_len); + if (ret < 0) { + /* Ret value is a valid lttng error code. */ + goto end; + } + + /* Send fds */ + ret = send_session_fds(fds, nb_fd); + if (ret < 0) { + /* Ret value is a valid lttng error code. */ + goto end; + } + + /* Get header from data transmission */ + ret = recv_data_sessiond(&llm, sizeof(llm)); + if (ret < 0) { + /* Ret value is a valid lttng error code. */ + goto end; + } + + /* Check error code if OK */ + if (llm.ret_code != LTTNG_OK) { + ret = -llm.ret_code; + goto end; + } + + /* Get command header from data transmission */ + ret = recv_sessiond_optional_data(llm.cmd_header_size, + user_cmd_header_buf, user_cmd_header_len); + if (ret < 0) { + goto end; + } + + /* Get payload from data transmission */ + ret = recv_sessiond_optional_data(llm.data_size, user_payload_buf, + &payload_len); + if (ret < 0) { + goto end; + } + + ret = llm.data_size; + +end: + disconnect_sessiond(); + return ret; +} + +int lttng_ctl_ask_sessiond_payload(struct lttng_payload_view *message, + struct lttng_payload *reply) +{ + int ret; + struct lttcomm_lttng_msg llm; + const int fd_count = lttng_payload_view_get_fd_handle_count(message); + + LTTNG_ASSERT(reply->buffer.size == 0); + LTTNG_ASSERT(lttng_dynamic_pointer_array_get_count(&reply->_fd_handles) == 0); + + ret = connect_sessiond(); + if (ret < 0) { + ret = -LTTNG_ERR_NO_SESSIOND; + goto end; + } else { + sessiond_socket = ret; + connected = 1; + } + + /* Send command to session daemon */ + ret = lttcomm_send_creds_unix_sock(sessiond_socket, message->buffer.data, + message->buffer.size); + if (ret < 0) { + ret = -LTTNG_ERR_FATAL; + goto end; + } + + if (fd_count > 0) { + ret = lttcomm_send_payload_view_fds_unix_sock(sessiond_socket, + message); + if (ret < 0) { + ret = -LTTNG_ERR_FATAL; + goto end; + } + } + + /* Get header from data transmission */ + ret = recv_payload_sessiond(reply, sizeof(llm)); + if (ret < 0) { + /* Ret value is a valid lttng error code. */ + goto end; + } + + llm = *((typeof(llm) *) reply->buffer.data); + + /* Check error code if OK */ + if (llm.ret_code != LTTNG_OK) { + if (llm.ret_code < LTTNG_OK || llm.ret_code >= LTTNG_ERR_NR) { + /* Invalid error code received. */ + ret = -LTTNG_ERR_UNK; + } else { + ret = -llm.ret_code; + } + goto end; + } + + if (llm.cmd_header_size > 0) { + ret = recv_payload_sessiond(reply, llm.cmd_header_size); + if (ret < 0) { + goto end; + } + } + + /* Get command header from data transmission */ + if (llm.data_size > 0) { + ret = recv_payload_sessiond(reply, llm.data_size); + if (ret < 0) { + goto end; + } + } + + if (llm.fd_count > 0) { + ret = lttcomm_recv_payload_fds_unix_sock( + sessiond_socket, llm.fd_count, reply); + if (ret < 0) { + goto end; + } + } + + /* Don't return the llm header to the caller. */ + memmove(reply->buffer.data, reply->buffer.data + sizeof(llm), + reply->buffer.size - sizeof(llm)); + ret = lttng_dynamic_buffer_set_size( + &reply->buffer, reply->buffer.size - sizeof(llm)); + if (ret) { + /* Can't happen as size is reduced. */ + abort(); + } + + ret = reply->buffer.size; + +end: + disconnect_sessiond(); + return ret; +} + +/* + * Create lttng handle and return pointer. + * + * The returned pointer will be NULL in case of malloc() error. + */ +struct lttng_handle *lttng_create_handle(const char *session_name, + struct lttng_domain *domain) +{ + int ret; + struct lttng_handle *handle = NULL; + + handle = (lttng_handle *) zmalloc(sizeof(struct lttng_handle)); + if (handle == NULL) { + PERROR("malloc handle"); + goto end; + } + + /* Copy session name */ + ret = lttng_strncpy(handle->session_name, session_name ? : "", + sizeof(handle->session_name)); + if (ret) { + goto error; + } + + /* Copy lttng domain or leave initialized to 0. */ + if (domain) { + lttng_ctl_copy_lttng_domain(&handle->domain, domain); + } + +end: + return handle; +error: + free(handle); + return NULL; +} + +/* + * Destroy handle by free(3) the pointer. + */ +void lttng_destroy_handle(struct lttng_handle *handle) +{ + free(handle); +} + +/* + * Register an outside consumer. + * + * Returns size of returned session payload data or a negative error code. + */ +int lttng_register_consumer(struct lttng_handle *handle, + const char *socket_path) +{ + int ret; + struct lttcomm_session_msg lsm; + + if (handle == NULL || socket_path == NULL) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + memset(&lsm, 0, sizeof(lsm)); + lsm.cmd_type = LTTNG_REGISTER_CONSUMER; + ret = lttng_strncpy(lsm.session.name, handle->session_name, + sizeof(lsm.session.name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + COPY_DOMAIN_PACKED(lsm.domain, handle->domain); + + ret = lttng_strncpy(lsm.u.reg.path, socket_path, + sizeof(lsm.u.reg.path)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + ret = lttng_ctl_ask_sessiond(&lsm, NULL); +end: + return ret; +} + +/* + * Start tracing for all traces of the session. + * + * Returns size of returned session payload data or a negative error code. + */ +int lttng_start_tracing(const char *session_name) +{ + int ret; + struct lttcomm_session_msg lsm; + + if (session_name == NULL) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + memset(&lsm, 0, sizeof(lsm)); + lsm.cmd_type = LTTNG_START_TRACE; + + ret = lttng_strncpy(lsm.session.name, session_name, + sizeof(lsm.session.name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + ret = lttng_ctl_ask_sessiond(&lsm, NULL); +end: + return ret; +} + +/* + * Stop tracing for all traces of the session. + */ +static int _lttng_stop_tracing(const char *session_name, int wait) +{ + int ret, data_ret; + struct lttcomm_session_msg lsm; + + if (session_name == NULL) { + ret = -LTTNG_ERR_INVALID; + goto error; + } + + memset(&lsm, 0, sizeof(lsm)); + lsm.cmd_type = LTTNG_STOP_TRACE; + + ret = lttng_strncpy(lsm.session.name, session_name, + sizeof(lsm.session.name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto error; + } + + ret = lttng_ctl_ask_sessiond(&lsm, NULL); + if (ret < 0 && ret != -LTTNG_ERR_TRACE_ALREADY_STOPPED) { + goto error; + } + + if (!wait) { + goto end; + } + + /* Check for data availability */ + do { + data_ret = lttng_data_pending(session_name); + if (data_ret < 0) { + /* Return the data available call error. */ + ret = data_ret; + goto error; + } + + /* + * Data sleep time before retrying (in usec). Don't sleep if the + * call returned value indicates availability. + */ + if (data_ret) { + usleep(DEFAULT_DATA_AVAILABILITY_WAIT_TIME_US); + } + } while (data_ret != 0); + +end: +error: + return ret; +} + +/* + * Stop tracing and wait for data availability. + */ +int lttng_stop_tracing(const char *session_name) +{ + return _lttng_stop_tracing(session_name, 1); +} + +/* + * Stop tracing but _don't_ wait for data availability. + */ +int lttng_stop_tracing_no_wait(const char *session_name) +{ + return _lttng_stop_tracing(session_name, 0); +} + +/* + * Add context to a channel. + * + * If the given channel is NULL, add the contexts to all channels. + * The event_name param is ignored. + * + * Returns the size of the returned payload data or a negative error code. + */ +int lttng_add_context(struct lttng_handle *handle, + struct lttng_event_context *ctx, const char *event_name, + const char *channel_name) +{ + int ret; + size_t len = 0; + char *buf = NULL; + struct lttcomm_session_msg lsm; + + /* Safety check. Both are mandatory. */ + if (handle == NULL || ctx == NULL) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + memset(&lsm, 0, sizeof(lsm)); + lsm.cmd_type = LTTNG_ADD_CONTEXT; + + /* If no channel name, send empty string. */ + ret = lttng_strncpy(lsm.u.context.channel_name, channel_name ?: "", + sizeof(lsm.u.context.channel_name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + COPY_DOMAIN_PACKED(lsm.domain, handle->domain); + ret = lttng_strncpy(lsm.session.name, handle->session_name, + sizeof(lsm.session.name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) { + size_t provider_len, ctx_len; + const char *provider_name = ctx->u.app_ctx.provider_name; + const char *ctx_name = ctx->u.app_ctx.ctx_name; + + if (!provider_name || !ctx_name) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + provider_len = strlen(provider_name); + if (provider_len == 0) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + lsm.u.context.provider_name_len = provider_len; + + ctx_len = strlen(ctx_name); + if (ctx_len == 0) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + lsm.u.context.context_name_len = ctx_len; + + len = provider_len + ctx_len; + buf = (char *) zmalloc(len); + if (!buf) { + ret = -LTTNG_ERR_NOMEM; + goto end; + } + + memcpy(buf, provider_name, provider_len); + memcpy(buf + provider_len, ctx_name, ctx_len); + } + memcpy(&lsm.u.context.ctx, ctx, sizeof(struct lttng_event_context)); + + if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) { + /* + * Don't leak application addresses to the sessiond. + * This is only necessary when ctx is for an app ctx otherwise + * the values inside the union (type & config) are overwritten. + */ + lsm.u.context.ctx.u.app_ctx.provider_name = NULL; + lsm.u.context.ctx.u.app_ctx.ctx_name = NULL; + } + + ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, buf, len, NULL); +end: + free(buf); + return ret; +} + +/* + * Enable event(s) for a channel. + * + * If no event name is specified, all events are enabled. + * If no channel name is specified, the default 'channel0' is used. + * + * Returns size of returned session payload data or a negative error code. + */ +int lttng_enable_event(struct lttng_handle *handle, + struct lttng_event *ev, const char *channel_name) +{ + return lttng_enable_event_with_exclusions(handle, ev, channel_name, + NULL, 0, NULL); +} + +/* + * Create or enable an event with a filter expression. + * + * Return negative error value on error. + * Return size of returned session payload data if OK. + */ +int lttng_enable_event_with_filter(struct lttng_handle *handle, + struct lttng_event *event, const char *channel_name, + const char *filter_expression) +{ + return lttng_enable_event_with_exclusions(handle, event, channel_name, + filter_expression, 0, NULL); +} + +/* + * Depending on the event, return a newly allocated agent filter expression or + * NULL if not applicable. + * + * An event with NO loglevel and the name is * will return NULL. + */ +static char *set_agent_filter(const char *filter, struct lttng_event *ev) +{ + int err; + char *agent_filter = NULL; + + LTTNG_ASSERT(ev); + + /* Don't add filter for the '*' event. */ + if (strcmp(ev->name, "*") != 0) { + if (filter) { + err = asprintf(&agent_filter, "(%s) && (logger_name == \"%s\")", filter, + ev->name); + } else { + err = asprintf(&agent_filter, "logger_name == \"%s\"", ev->name); + } + if (err < 0) { + PERROR("asprintf"); + goto error; + } + } + + /* Add loglevel filtering if any for the JUL domain. */ + if (ev->loglevel_type != LTTNG_EVENT_LOGLEVEL_ALL) { + const char *op; + + if (ev->loglevel_type == LTTNG_EVENT_LOGLEVEL_RANGE) { + op = ">="; + } else { + op = "=="; + } + + if (filter || agent_filter) { + char *new_filter; + + err = asprintf(&new_filter, "(%s) && (int_loglevel %s %d)", + agent_filter ? agent_filter : filter, op, + ev->loglevel); + if (agent_filter) { + free(agent_filter); + } + agent_filter = new_filter; + } else { + err = asprintf(&agent_filter, "int_loglevel %s %d", op, + ev->loglevel); + } + if (err < 0) { + PERROR("asprintf"); + goto error; + } + } + + return agent_filter; +error: + free(agent_filter); + return NULL; +} + +/* + * Enable event(s) for a channel, possibly with exclusions and a filter. + * If no event name is specified, all events are enabled. + * If no channel name is specified, the default name is used. + * If filter expression is not NULL, the filter is set for the event. + * If exclusion count is not zero, the exclusions are set for the event. + * Returns size of returned session payload data or a negative error code. + */ +int lttng_enable_event_with_exclusions(struct lttng_handle *handle, + struct lttng_event *ev, const char *channel_name, + const char *original_filter_expression, + int exclusion_count, char **exclusion_list) +{ + struct lttcomm_session_msg lsm; + struct lttng_payload payload; + int ret = 0, i; + unsigned int free_filter_expression = 0; + struct filter_parser_ctx *ctx = NULL; + + /* + * We have either a filter or some exclusions, so we need to set up + * a variable-length payload from where to send the data. + */ + lttng_payload_init(&payload); + + /* + * Cast as non-const since we may replace the filter expression + * by a dynamically allocated string. Otherwise, the original + * string is not modified. + */ + char *filter_expression = (char *) original_filter_expression; + + if (handle == NULL || ev == NULL) { + ret = -LTTNG_ERR_INVALID; + goto error; + } + + /* + * Empty filter string will always be rejected by the parser + * anyway, so treat this corner-case early to eliminate + * lttng_fmemopen error for 0-byte allocation. + */ + if (filter_expression && filter_expression[0] == '\0') { + ret = -LTTNG_ERR_INVALID; + goto error; + } + + memset(&lsm, 0, sizeof(lsm)); + + /* If no channel name, send empty string. */ + ret = lttng_strncpy(lsm.u.enable.channel_name, channel_name ?: "", + sizeof(lsm.u.enable.channel_name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto error; + } + + lsm.cmd_type = LTTNG_ENABLE_EVENT; + if (ev->name[0] == '\0') { + /* Enable all events. */ + ret = lttng_strncpy(ev->name, "*", sizeof(ev->name)); + LTTNG_ASSERT(ret == 0); + } + + COPY_DOMAIN_PACKED(lsm.domain, handle->domain); + memcpy(&lsm.u.enable.event, ev, sizeof(lsm.u.enable.event)); + + ret = lttng_strncpy(lsm.session.name, handle->session_name, + sizeof(lsm.session.name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto error; + } + + lsm.u.enable.exclusion_count = exclusion_count; + lsm.u.enable.bytecode_len = 0; + + /* Parse filter expression. */ + if (filter_expression != NULL || handle->domain.type == LTTNG_DOMAIN_JUL + || handle->domain.type == LTTNG_DOMAIN_LOG4J + || handle->domain.type == LTTNG_DOMAIN_PYTHON) { + if (handle->domain.type == LTTNG_DOMAIN_JUL || + handle->domain.type == LTTNG_DOMAIN_LOG4J || + handle->domain.type == LTTNG_DOMAIN_PYTHON) { + char *agent_filter; + + /* Setup JUL filter if needed. */ + agent_filter = set_agent_filter(filter_expression, ev); + if (!agent_filter) { + if (!filter_expression) { + /* + * No JUL and no filter, just skip + * everything below. + */ + goto ask_sessiond; + } + } else { + /* + * With an agent filter, the original filter has + * been added to it thus replace the filter + * expression. + */ + filter_expression = agent_filter; + free_filter_expression = 1; + } + } + + ret = filter_parser_ctx_create_from_filter_expression(filter_expression, &ctx); + if (ret) { + goto filter_error; + } + + lsm.u.enable.bytecode_len = sizeof(ctx->bytecode->b) + + bytecode_get_len(&ctx->bytecode->b); + lsm.u.enable.expression_len = strlen(filter_expression) + 1; + } + + ret = lttng_dynamic_buffer_set_capacity(&payload.buffer, + lsm.u.enable.bytecode_len + + lsm.u.enable.expression_len + + LTTNG_SYMBOL_NAME_LEN * + exclusion_count); + if (ret) { + ret = -LTTNG_ERR_EXCLUSION_NOMEM; + goto mem_error; + } + + /* Put exclusion names first in the data. */ + for (i = 0; i < exclusion_count; i++) { + size_t exclusion_len; + + exclusion_len = lttng_strnlen(exclusion_list[i], + LTTNG_SYMBOL_NAME_LEN); + if (exclusion_len == LTTNG_SYMBOL_NAME_LEN) { + /* Exclusion is not NULL-terminated. */ + ret = -LTTNG_ERR_INVALID; + goto mem_error; + } + + ret = lttng_dynamic_buffer_append(&payload.buffer, + exclusion_list[i], exclusion_len); + if (ret) { + goto mem_error; + } + + /* + * Padding the rest of the entry with zeros. Every exclusion + * entries take LTTNG_SYMBOL_NAME_LEN bytes in the buffer. + */ + ret = lttng_dynamic_buffer_set_size(&payload.buffer, + LTTNG_SYMBOL_NAME_LEN * (i + 1)); + if (ret) { + goto mem_error; + } + } + + /* Add filter expression next. */ + if (filter_expression) { + ret = lttng_dynamic_buffer_append(&payload.buffer, + filter_expression, lsm.u.enable.expression_len); + if (ret) { + goto mem_error; + } + } + /* Add filter bytecode next. */ + if (ctx && lsm.u.enable.bytecode_len != 0) { + ret = lttng_dynamic_buffer_append(&payload.buffer, + &ctx->bytecode->b, lsm.u.enable.bytecode_len); + if (ret) { + goto mem_error; + } + } + if (ev->extended.ptr) { + struct lttng_event_extended *ev_ext = + (struct lttng_event_extended *) ev->extended.ptr; + + if (ev_ext->probe_location) { + /* + * lttng_userspace_probe_location_serialize returns the + * number of bytes that was appended to the buffer. + */ + ret = lttng_userspace_probe_location_serialize( + ev_ext->probe_location, &payload); + if (ret < 0) { + goto mem_error; + } + + /* + * Set the size of the userspace probe location element + * of the buffer so that the receiving side knows where + * to split it. + */ + lsm.u.enable.userspace_probe_location_len = ret; + } + } + + { + struct lttng_payload_view view = lttng_payload_view_from_payload( + &payload, 0, -1); + int fd_count = lttng_payload_view_get_fd_handle_count(&view); + int fd_to_send; + + if (fd_count < 0) { + goto mem_error; + } + + LTTNG_ASSERT(fd_count == 0 || fd_count == 1); + if (fd_count == 1) { + struct fd_handle *h = + lttng_payload_view_pop_fd_handle(&view); + + if (!h) { + goto mem_error; + } + + fd_to_send = fd_handle_get_fd(h); + fd_handle_put(h); + } + + ret = lttng_ctl_ask_sessiond_fds_varlen(&lsm, + fd_count ? &fd_to_send : NULL, fd_count, + view.buffer.size ? view.buffer.data : NULL, + view.buffer.size, NULL, NULL, 0); + } + +mem_error: + if (filter_expression && ctx) { + filter_bytecode_free(ctx); + filter_ir_free(ctx); + filter_parser_ctx_free(ctx); + } +filter_error: + if (free_filter_expression) { + /* + * The filter expression has been replaced and must be freed as + * it is not the original filter expression received as a + * parameter. + */ + free(filter_expression); + } +error: + /* + * Return directly to the caller and don't ask the sessiond since + * something went wrong in the parsing of data above. + */ + lttng_payload_reset(&payload); + return ret; + +ask_sessiond: + ret = lttng_ctl_ask_sessiond(&lsm, NULL); + return ret; +} + +int lttng_disable_event_ext(struct lttng_handle *handle, + struct lttng_event *ev, const char *channel_name, + const char *original_filter_expression) +{ + struct lttcomm_session_msg lsm; + char *varlen_data; + int ret = 0; + unsigned int free_filter_expression = 0; + struct filter_parser_ctx *ctx = NULL; + /* + * Cast as non-const since we may replace the filter expression + * by a dynamically allocated string. Otherwise, the original + * string is not modified. + */ + char *filter_expression = (char *) original_filter_expression; + + if (handle == NULL || ev == NULL) { + ret = -LTTNG_ERR_INVALID; + goto error; + } + + /* + * Empty filter string will always be rejected by the parser + * anyway, so treat this corner-case early to eliminate + * lttng_fmemopen error for 0-byte allocation. + */ + if (filter_expression && filter_expression[0] == '\0') { + ret = -LTTNG_ERR_INVALID; + goto error; + } + + memset(&lsm, 0, sizeof(lsm)); + + /* If no channel name, send empty string. */ + ret = lttng_strncpy(lsm.u.disable.channel_name, channel_name ?: "", + sizeof(lsm.u.disable.channel_name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto error; + } + + lsm.cmd_type = LTTNG_DISABLE_EVENT; + + COPY_DOMAIN_PACKED(lsm.domain, handle->domain); + memcpy(&lsm.u.disable.event, ev, sizeof(lsm.u.disable.event)); + + ret = lttng_strncpy(lsm.session.name, handle->session_name, + sizeof(lsm.session.name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto error; + } + + lsm.u.disable.bytecode_len = 0; + + /* + * For the JUL domain, a filter is enforced except for the + * disable all event. This is done to avoid having the event in + * all sessions thus filtering by logger name. + */ + if (filter_expression == NULL && + (handle->domain.type != LTTNG_DOMAIN_JUL && + handle->domain.type != LTTNG_DOMAIN_LOG4J && + handle->domain.type != LTTNG_DOMAIN_PYTHON)) { + goto ask_sessiond; + } + + /* + * We have a filter, so we need to set up a variable-length + * memory block from where to send the data. + */ + + /* Parse filter expression */ + if (filter_expression != NULL || handle->domain.type == LTTNG_DOMAIN_JUL + || handle->domain.type == LTTNG_DOMAIN_LOG4J + || handle->domain.type == LTTNG_DOMAIN_PYTHON) { + if (handle->domain.type == LTTNG_DOMAIN_JUL || + handle->domain.type == LTTNG_DOMAIN_LOG4J || + handle->domain.type == LTTNG_DOMAIN_PYTHON) { + char *agent_filter; + + /* Setup JUL filter if needed. */ + agent_filter = set_agent_filter(filter_expression, ev); + if (!agent_filter) { + if (!filter_expression) { + /* + * No JUL and no filter, just skip + * everything below. + */ + goto ask_sessiond; + } + } else { + /* + * With a JUL filter, the original filter has + * been added to it thus replace the filter + * expression. + */ + filter_expression = agent_filter; + free_filter_expression = 1; + } + } + + ret = filter_parser_ctx_create_from_filter_expression(filter_expression, &ctx); + if (ret) { + goto filter_error; + } + + lsm.u.enable.bytecode_len = sizeof(ctx->bytecode->b) + + bytecode_get_len(&ctx->bytecode->b); + lsm.u.enable.expression_len = strlen(filter_expression) + 1; + } + + varlen_data = (char *) zmalloc(lsm.u.disable.bytecode_len + + lsm.u.disable.expression_len); + if (!varlen_data) { + ret = -LTTNG_ERR_EXCLUSION_NOMEM; + goto mem_error; + } + + /* Add filter expression. */ + if (lsm.u.disable.expression_len != 0) { + memcpy(varlen_data, + filter_expression, + lsm.u.disable.expression_len); + } + /* Add filter bytecode next. */ + if (ctx && lsm.u.disable.bytecode_len != 0) { + memcpy(varlen_data + + lsm.u.disable.expression_len, + &ctx->bytecode->b, + lsm.u.disable.bytecode_len); + } + + ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, varlen_data, + lsm.u.disable.bytecode_len + lsm.u.disable.expression_len, NULL); + free(varlen_data); + +mem_error: + if (filter_expression && ctx) { + filter_bytecode_free(ctx); + filter_ir_free(ctx); + filter_parser_ctx_free(ctx); + } +filter_error: + if (free_filter_expression) { + /* + * The filter expression has been replaced and must be freed as + * it is not the original filter expression received as a + * parameter. + */ + free(filter_expression); + } +error: + /* + * Return directly to the caller and don't ask the sessiond since + * something went wrong in the parsing of data above. + */ + return ret; + +ask_sessiond: + ret = lttng_ctl_ask_sessiond(&lsm, NULL); + return ret; +} + +/* + * Disable event(s) of a channel and domain. + * If no event name is specified, all events are disabled. + * If no channel name is specified, the default 'channel0' is used. + * Returns size of returned session payload data or a negative error code. + */ +int lttng_disable_event(struct lttng_handle *handle, const char *name, + const char *channel_name) +{ + int ret; + struct lttng_event ev; + + memset(&ev, 0, sizeof(ev)); + ev.loglevel = -1; + ev.type = LTTNG_EVENT_ALL; + ret = lttng_strncpy(ev.name, name ?: "", sizeof(ev.name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + ret = lttng_disable_event_ext(handle, &ev, channel_name, NULL); +end: + return ret; +} + +struct lttng_channel *lttng_channel_create(struct lttng_domain *domain) +{ + struct lttng_channel *channel = NULL; + struct lttng_channel_extended *extended = NULL; + + if (!domain) { + goto error; + } + + /* Validate domain. */ + switch (domain->type) { + case LTTNG_DOMAIN_UST: + switch (domain->buf_type) { + case LTTNG_BUFFER_PER_UID: + case LTTNG_BUFFER_PER_PID: + break; + default: + goto error; + } + break; + case LTTNG_DOMAIN_KERNEL: + if (domain->buf_type != LTTNG_BUFFER_GLOBAL) { + goto error; + } + break; + default: + goto error; + } + + channel = (lttng_channel *) zmalloc(sizeof(*channel)); + if (!channel) { + goto error; + } + + extended = (lttng_channel_extended *) zmalloc(sizeof(*extended)); + if (!extended) { + goto error; + } + + channel->attr.extended.ptr = extended; + + lttng_channel_set_default_attr(domain, &channel->attr); + return channel; +error: + free(channel); + free(extended); + return NULL; +} + +void lttng_channel_destroy(struct lttng_channel *channel) +{ + if (!channel) { + return; + } + + if (channel->attr.extended.ptr) { + free(channel->attr.extended.ptr); + } + free(channel); +} + +/* + * Enable channel per domain + * Returns size of returned session payload data or a negative error code. + */ +int lttng_enable_channel(struct lttng_handle *handle, + struct lttng_channel *in_chan) +{ + int ret; + struct lttcomm_session_msg lsm; + size_t total_buffer_size_needed_per_cpu = 0; + + /* NULL arguments are forbidden. No default values. */ + if (handle == NULL || in_chan == NULL) { + return -LTTNG_ERR_INVALID; + } + + memset(&lsm, 0, sizeof(lsm)); + memcpy(&lsm.u.channel.chan, in_chan, sizeof(lsm.u.channel.chan)); + lsm.u.channel.chan.attr.extended.ptr = NULL; + + if (!in_chan->attr.extended.ptr) { + struct lttng_channel *channel; + struct lttng_channel_extended *extended; + + channel = lttng_channel_create(&handle->domain); + if (!channel) { + return -LTTNG_ERR_NOMEM; + } + + /* + * Create a new channel in order to use default extended + * attribute values. + */ + extended = (struct lttng_channel_extended *) + channel->attr.extended.ptr; + memcpy(&lsm.u.channel.extended, extended, sizeof(*extended)); + lttng_channel_destroy(channel); + } else { + struct lttng_channel_extended *extended; + + extended = (struct lttng_channel_extended *) + in_chan->attr.extended.ptr; + memcpy(&lsm.u.channel.extended, extended, sizeof(*extended)); + } + + /* + * Verify that the amount of memory required to create the requested + * buffer is available on the system at the moment. + */ + total_buffer_size_needed_per_cpu = lsm.u.channel.chan.attr.num_subbuf * + lsm.u.channel.chan.attr.subbuf_size; + if (!check_enough_available_memory(total_buffer_size_needed_per_cpu)) { + return -LTTNG_ERR_NOMEM; + } + + lsm.cmd_type = LTTNG_ENABLE_CHANNEL; + COPY_DOMAIN_PACKED(lsm.domain, handle->domain); + + ret = lttng_strncpy(lsm.session.name, handle->session_name, + sizeof(lsm.session.name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + ret = lttng_ctl_ask_sessiond(&lsm, NULL); +end: + return ret; +} + +/* + * All tracing will be stopped for registered events of the channel. + * Returns size of returned session payload data or a negative error code. + */ +int lttng_disable_channel(struct lttng_handle *handle, const char *name) +{ + int ret; + struct lttcomm_session_msg lsm; + + /* Safety check. Both are mandatory. */ + if (handle == NULL || name == NULL) { + return -LTTNG_ERR_INVALID; + } + + memset(&lsm, 0, sizeof(lsm)); + + lsm.cmd_type = LTTNG_DISABLE_CHANNEL; + + ret = lttng_strncpy(lsm.u.disable.channel_name, name, + sizeof(lsm.u.disable.channel_name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + COPY_DOMAIN_PACKED(lsm.domain, handle->domain); + + ret = lttng_strncpy(lsm.session.name, handle->session_name, + sizeof(lsm.session.name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + ret = lttng_ctl_ask_sessiond(&lsm, NULL); +end: + return ret; +} + +/* + * Lists all available tracepoints of domain. + * Sets the contents of the events array. + * Returns the number of lttng_event entries in events; + * on error, returns a negative value. + */ +int lttng_list_tracepoints(struct lttng_handle *handle, + struct lttng_event **events) +{ + int ret; + struct lttcomm_session_msg lsm; + + if (handle == NULL) { + return -LTTNG_ERR_INVALID; + } + + memset(&lsm, 0, sizeof(lsm)); + lsm.cmd_type = LTTNG_LIST_TRACEPOINTS; + COPY_DOMAIN_PACKED(lsm.domain, handle->domain); + + ret = lttng_ctl_ask_sessiond(&lsm, (void **) events); + if (ret < 0) { + return ret; + } + + return ret / sizeof(struct lttng_event); +} + +/* + * Lists all available tracepoint fields of domain. + * Sets the contents of the event field array. + * Returns the number of lttng_event_field entries in events; + * on error, returns a negative value. + */ +int lttng_list_tracepoint_fields(struct lttng_handle *handle, + struct lttng_event_field **fields) +{ + int ret; + struct lttcomm_session_msg lsm; + + if (handle == NULL) { + return -LTTNG_ERR_INVALID; + } + + memset(&lsm, 0, sizeof(lsm)); + lsm.cmd_type = LTTNG_LIST_TRACEPOINT_FIELDS; + COPY_DOMAIN_PACKED(lsm.domain, handle->domain); + + ret = lttng_ctl_ask_sessiond(&lsm, (void **) fields); + if (ret < 0) { + return ret; + } + + return ret / sizeof(struct lttng_event_field); +} + +/* + * Lists all available kernel system calls. Allocates and sets the contents of + * the events array. + * + * Returns the number of lttng_event entries in events; on error, returns a + * negative value. + */ +int lttng_list_syscalls(struct lttng_event **events) +{ + int ret; + struct lttcomm_session_msg lsm; + + if (!events) { + return -LTTNG_ERR_INVALID; + } + + memset(&lsm, 0, sizeof(lsm)); + lsm.cmd_type = LTTNG_LIST_SYSCALLS; + /* Force kernel domain for system calls. */ + lsm.domain.type = LTTNG_DOMAIN_KERNEL; + + ret = lttng_ctl_ask_sessiond(&lsm, (void **) events); + if (ret < 0) { + return ret; + } + + return ret / sizeof(struct lttng_event); +} + +/* + * Returns a human readable string describing + * the error code (a negative value). + */ +const char *lttng_strerror(int code) +{ + return error_get_str(code); +} + +enum lttng_error_code lttng_create_session_ext( + struct lttng_session_descriptor *session_descriptor) +{ + enum lttng_error_code ret_code; + struct lttcomm_session_msg lsm = { + .cmd_type = LTTNG_CREATE_SESSION_EXT, + }; + void *reply = NULL; + struct lttng_buffer_view reply_view; + int reply_ret; + bool sessiond_must_generate_ouput; + struct lttng_dynamic_buffer payload; + int ret; + size_t descriptor_size; + struct lttng_session_descriptor *descriptor_reply = NULL; + + lttng_dynamic_buffer_init(&payload); + if (!session_descriptor) { + ret_code = LTTNG_ERR_INVALID; + goto end; + } + + sessiond_must_generate_ouput = + !lttng_session_descriptor_is_output_destination_initialized( + session_descriptor); + if (sessiond_must_generate_ouput) { + const char *home_dir = utils_get_home_dir(); + size_t home_dir_len = home_dir ? strlen(home_dir) + 1 : 0; + + if (!home_dir || home_dir_len > LTTNG_PATH_MAX) { + ret_code = LTTNG_ERR_FATAL; + goto end; + } + + lsm.u.create_session.home_dir_size = (uint16_t) home_dir_len; + ret = lttng_dynamic_buffer_append(&payload, home_dir, + home_dir_len); + if (ret) { + ret_code = LTTNG_ERR_NOMEM; + goto end; + } + } + + descriptor_size = payload.size; + ret = lttng_session_descriptor_serialize(session_descriptor, + &payload); + if (ret) { + ret_code = LTTNG_ERR_INVALID; + goto end; + } + descriptor_size = payload.size - descriptor_size; + lsm.u.create_session.session_descriptor_size = descriptor_size; + + /* Command returns a session descriptor on success. */ + reply_ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, payload.data, + payload.size, &reply); + if (reply_ret < 0) { + ret_code = (lttng_error_code) -reply_ret; + goto end; + } else if (reply_ret == 0) { + /* Socket unexpectedly closed by the session daemon. */ + ret_code = LTTNG_ERR_FATAL; + goto end; + } + + reply_view = lttng_buffer_view_init((const char *) reply, 0, reply_ret); + ret = lttng_session_descriptor_create_from_buffer(&reply_view, + &descriptor_reply); + if (ret < 0) { + ret_code = LTTNG_ERR_FATAL; + goto end; + } + ret_code = LTTNG_OK; + lttng_session_descriptor_assign(session_descriptor, descriptor_reply); +end: + free(reply); + lttng_dynamic_buffer_reset(&payload); + lttng_session_descriptor_destroy(descriptor_reply); + return ret_code; +} + +/* + * Create a new session using name and url for destination. + * + * Return 0 on success else a negative LTTng error code. + */ +int lttng_create_session(const char *name, const char *url) +{ + int ret; + ssize_t size; + struct lttng_uri *uris = NULL; + struct lttng_session_descriptor *descriptor = NULL; + enum lttng_error_code ret_code; + + if (!name) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + size = uri_parse_str_urls(url, NULL, &uris); + if (size < 0) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + switch (size) { + case 0: + descriptor = lttng_session_descriptor_create(name); + break; + case 1: + if (uris[0].dtype != LTTNG_DST_PATH) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + descriptor = lttng_session_descriptor_local_create(name, + uris[0].dst.path); + break; + case 2: + descriptor = lttng_session_descriptor_network_create(name, url, + NULL); + break; + default: + ret = -LTTNG_ERR_INVALID; + goto end; + } + if (!descriptor) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + ret_code = lttng_create_session_ext(descriptor); + ret = ret_code == LTTNG_OK ? 0 : -ret_code; +end: + lttng_session_descriptor_destroy(descriptor); + free(uris); + return ret; +} + +/* + * Create a session exclusively used for snapshot. + * + * Return 0 on success else a negative LTTng error code. + */ +int lttng_create_session_snapshot(const char *name, const char *snapshot_url) +{ + int ret; + enum lttng_error_code ret_code; + ssize_t size; + struct lttng_uri *uris = NULL; + struct lttng_session_descriptor *descriptor = NULL; + + if (!name) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + size = uri_parse_str_urls(snapshot_url, NULL, &uris); + if (size < 0) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + /* + * If the user does not specify a custom subdir, use the session name. + */ + if (size > 0 && uris[0].dtype != LTTNG_DST_PATH && + strlen(uris[0].subdir) == 0) { + ret = snprintf(uris[0].subdir, sizeof(uris[0].subdir), "%s", + name); + if (ret < 0) { + PERROR("Failed to set session name as network destination sub-directory"); + ret = -LTTNG_ERR_FATAL; + goto end; + } else if (ret >= sizeof(uris[0].subdir)) { + /* Truncated output. */ + ret = -LTTNG_ERR_INVALID; + goto end; + } + } + + switch (size) { + case 0: + descriptor = lttng_session_descriptor_snapshot_create(name); + break; + case 1: + if (uris[0].dtype != LTTNG_DST_PATH) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + descriptor = lttng_session_descriptor_snapshot_local_create( + name, + uris[0].dst.path); + break; + case 2: + descriptor = lttng_session_descriptor_snapshot_network_create( + name, + snapshot_url, + NULL); + break; + default: + ret = -LTTNG_ERR_INVALID; + goto end; + } + if (!descriptor) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + ret_code = lttng_create_session_ext(descriptor); + ret = ret_code == LTTNG_OK ? 0 : -ret_code; +end: + lttng_session_descriptor_destroy(descriptor); + free(uris); + return ret; +} + +/* + * Create a session exclusively used for live. + * + * Return 0 on success else a negative LTTng error code. + */ +int lttng_create_session_live(const char *name, const char *url, + unsigned int timer_interval) +{ + int ret; + enum lttng_error_code ret_code; + struct lttng_session_descriptor *descriptor = NULL; + + if (!name) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + if (url) { + descriptor = lttng_session_descriptor_live_network_create( + name, url, NULL, timer_interval); + } else { + descriptor = lttng_session_descriptor_live_create( + name, timer_interval); + } + if (!descriptor) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + ret_code = lttng_create_session_ext(descriptor); + ret = ret_code == LTTNG_OK ? 0 : -ret_code; +end: + lttng_session_descriptor_destroy(descriptor); + return ret; +} + +/* + * Stop the session and wait for the data before destroying it + * + * Return 0 on success else a negative LTTng error code. + */ +int lttng_destroy_session(const char *session_name) +{ + int ret; + enum lttng_error_code ret_code; + enum lttng_destruction_handle_status status; + struct lttng_destruction_handle *handle = NULL; + + /* + * Stop the tracing and wait for the data to be + * consumed. + */ + ret = _lttng_stop_tracing(session_name, 1); + if (ret && ret != -LTTNG_ERR_TRACE_ALREADY_STOPPED) { + goto end; + } + + ret_code = lttng_destroy_session_ext(session_name, &handle); + if (ret_code != LTTNG_OK) { + ret = (int) -ret_code; + goto end; + } + LTTNG_ASSERT(handle); + + /* Block until the completion of the destruction of the session. */ + status = lttng_destruction_handle_wait_for_completion(handle, -1); + if (status != LTTNG_DESTRUCTION_HANDLE_STATUS_COMPLETED) { + ret = -LTTNG_ERR_UNK; + goto end; + } + + status = lttng_destruction_handle_get_result(handle, &ret_code); + if (status != LTTNG_DESTRUCTION_HANDLE_STATUS_OK) { + ret = -LTTNG_ERR_UNK; + goto end; + } + ret = ret_code == LTTNG_OK ? 0 : -ret_code; +end: + lttng_destruction_handle_destroy(handle); + return ret; +} + +/* + * Destroy the session without waiting for the data. + */ +int lttng_destroy_session_no_wait(const char *session_name) +{ + enum lttng_error_code ret_code; + + ret_code = lttng_destroy_session_ext(session_name, NULL); + return ret_code == LTTNG_OK ? 0 : -ret_code; +} + +/* + * Ask the session daemon for all available sessions. + * Sets the contents of the sessions array. + * Returns the number of lttng_session entries in sessions; + * on error, returns a negative value. + */ +int lttng_list_sessions(struct lttng_session **out_sessions) +{ + int ret; + struct lttcomm_session_msg lsm; + const size_t session_size = sizeof(struct lttng_session) + + sizeof(struct lttng_session_extended); + size_t session_count, i; + struct lttng_session_extended *sessions_extended_begin; + struct lttng_session *sessions = NULL; + + memset(&lsm, 0, sizeof(lsm)); + lsm.cmd_type = LTTNG_LIST_SESSIONS; + ret = lttng_ctl_ask_sessiond(&lsm, (void**) &sessions); + if (ret <= 0) { + goto end; + } + if (!sessions) { + ret = -LTTNG_ERR_FATAL; + goto end; + } + + if (ret % session_size) { + ret = -LTTNG_ERR_UNK; + free(sessions); + *out_sessions = NULL; + goto end; + } + session_count = (size_t) ret / session_size; + sessions_extended_begin = (struct lttng_session_extended *) + (&sessions[session_count]); + + /* Set extended session info pointers. */ + for (i = 0; i < session_count; i++) { + struct lttng_session *session = &sessions[i]; + struct lttng_session_extended *extended = + &(sessions_extended_begin[i]); + + session->extended.ptr = extended; + } + + ret = (int) session_count; + *out_sessions = sessions; +end: + return ret; +} + +enum lttng_error_code lttng_session_get_creation_time( + const struct lttng_session *session, uint64_t *creation_time) +{ + enum lttng_error_code ret = LTTNG_OK; + struct lttng_session_extended *extended; + + if (!session || !creation_time || !session->extended.ptr) { + ret = LTTNG_ERR_INVALID; + goto end; + } + + extended = (lttng_session_extended *) session->extended.ptr; + if (!extended->creation_time.is_set) { + /* Not created on the session daemon yet. */ + ret = LTTNG_ERR_SESSION_NOT_EXIST; + goto end; + } + *creation_time = extended->creation_time.value; +end: + return ret; +} + +int lttng_set_session_shm_path(const char *session_name, + const char *shm_path) +{ + int ret; + struct lttcomm_session_msg lsm; + + if (session_name == NULL) { + return -LTTNG_ERR_INVALID; + } + + memset(&lsm, 0, sizeof(lsm)); + lsm.cmd_type = LTTNG_SET_SESSION_SHM_PATH; + + ret = lttng_strncpy(lsm.session.name, session_name, + sizeof(lsm.session.name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + ret = lttng_strncpy(lsm.u.set_shm_path.shm_path, shm_path ?: "", + sizeof(lsm.u.set_shm_path.shm_path)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + ret = lttng_ctl_ask_sessiond(&lsm, NULL); +end: + return ret; +} + +/* + * Ask the session daemon for all available domains of a session. + * Sets the contents of the domains array. + * Returns the number of lttng_domain entries in domains; + * on error, returns a negative value. + */ +int lttng_list_domains(const char *session_name, + struct lttng_domain **domains) +{ + int ret; + struct lttcomm_session_msg lsm; + + if (session_name == NULL) { + ret = -LTTNG_ERR_INVALID; + goto error; + } + + memset(&lsm, 0, sizeof(lsm)); + lsm.cmd_type = LTTNG_LIST_DOMAINS; + + ret = lttng_strncpy(lsm.session.name, session_name, + sizeof(lsm.session.name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto error; + } + + ret = lttng_ctl_ask_sessiond(&lsm, (void**) domains); + if (ret < 0) { + goto error; + } + + return ret / sizeof(struct lttng_domain); +error: + return ret; +} + +/* + * Ask the session daemon for all available channels of a session. + * Sets the contents of the channels array. + * Returns the number of lttng_channel entries in channels; + * on error, returns a negative value. + */ +int lttng_list_channels(struct lttng_handle *handle, + struct lttng_channel **channels) +{ + int ret; + size_t channel_count, i; + const size_t channel_size = sizeof(struct lttng_channel) + + sizeof(struct lttng_channel_extended); + struct lttcomm_session_msg lsm; + char *extended_at; + + if (handle == NULL) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + memset(&lsm, 0, sizeof(lsm)); + lsm.cmd_type = LTTNG_LIST_CHANNELS; + ret = lttng_strncpy(lsm.session.name, handle->session_name, + sizeof(lsm.session.name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + COPY_DOMAIN_PACKED(lsm.domain, handle->domain); + + ret = lttng_ctl_ask_sessiond(&lsm, (void**) channels); + if (ret < 0) { + goto end; + } + + if (ret % channel_size) { + ret = -LTTNG_ERR_UNK; + free(*channels); + *channels = NULL; + goto end; + } + channel_count = (size_t) ret / channel_size; + + /* Set extended info pointers */ + extended_at = ((char *) *channels) + + channel_count * sizeof(struct lttng_channel); + for (i = 0; i < channel_count; i++) { + struct lttng_channel *chan = &(*channels)[i]; + + chan->attr.extended.ptr = extended_at; + extended_at += sizeof(struct lttng_channel_extended); + } + + ret = (int) channel_count; +end: + return ret; +} + +/* + * Ask the session daemon for all available events of a session channel. + * Sets the contents of the events array. + * Returns the number of lttng_event entries in events; + * on error, returns a negative value. + */ +int lttng_list_events(struct lttng_handle *handle, + const char *channel_name, struct lttng_event **events) +{ + int ret; + struct lttcomm_session_msg lsm = {}; + const struct lttcomm_event_command_header *cmd_header = NULL; + uint32_t nb_events, i; + const char *comm_ext_at; + struct lttng_dynamic_buffer listing; + size_t storage_req; + struct lttng_payload payload; + struct lttng_payload payload_copy; + struct lttng_payload_view lsm_view = + lttng_payload_view_init_from_buffer( + (const char *) &lsm, 0, sizeof(lsm)); + struct lttng_buffer_view cmd_header_view; + struct lttng_buffer_view cmd_payload_view; + struct lttng_buffer_view flat_events_view; + struct lttng_buffer_view ext_view; + + /* Safety check. An handle and channel name are mandatory */ + if (handle == NULL || channel_name == NULL) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + lttng_payload_init(&payload); + lttng_payload_init(&payload_copy); + + lsm.cmd_type = LTTNG_LIST_EVENTS; + ret = lttng_strncpy(lsm.session.name, handle->session_name, + sizeof(lsm.session.name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + ret = lttng_strncpy(lsm.u.list.channel_name, channel_name, + sizeof(lsm.u.list.channel_name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + COPY_DOMAIN_PACKED(lsm.domain, handle->domain); + + ret = lttng_ctl_ask_sessiond_payload(&lsm_view, &payload); + if (ret < 0) { + goto end; + } + + /* + * A copy of the payload is performed since it will be + * consumed twice. Consuming the same payload twice is invalid since + * it will cause any received file descriptor to become "shared" + * between different instances of the resulting objects. + */ + ret = lttng_payload_copy(&payload, &payload_copy); + if (ret) { + ret = -LTTNG_ERR_NOMEM; + goto end; + } + + cmd_header_view = lttng_buffer_view_from_dynamic_buffer( + &payload.buffer, 0, sizeof(*cmd_header)); + if (!lttng_buffer_view_is_valid(&cmd_header_view)) { + ret = -LTTNG_ERR_INVALID_PROTOCOL; + goto end; + } + + cmd_header = (typeof(cmd_header)) cmd_header_view.data; + + /* Set number of events and free command header */ + nb_events = cmd_header->nb_events; + if (nb_events > INT_MAX) { + ret = -LTTNG_ERR_OVERFLOW; + goto end; + } + + cmd_payload_view = lttng_buffer_view_from_dynamic_buffer( + &payload.buffer, sizeof(*cmd_header), -1); + + /* + * The buffer that is returned must contain a "flat" version of + * the events that are returned. In other words, all pointers + * within an lttng_event must point to a location within the returned + * buffer so that the user may free everything by simply calling free() + * on the returned buffer. This is needed in order to maintain API + * compatibility. + * + * A first pass is performed to compute the size of the buffer that + * must be allocated. A second pass is then performed to setup + * the returned events so that their members always point within the + * buffer. + * + * The layout of the returned buffer is as follows: + * - struct lttng_event[nb_events], + * - nb_events times the following: + * - struct lttng_event_extended, + * - flattened version of userspace_probe_location + * - filter_expression + * - exclusions + * - padding to align to 64-bits + */ + ext_view = lttng_buffer_view_from_view(&cmd_payload_view, + nb_events * sizeof(struct lttng_event), -1); + comm_ext_at = ext_view.data; + storage_req = nb_events * sizeof(struct lttng_event); + { + struct lttng_payload_view payload_view = + lttng_payload_view_from_payload(&payload, 0, -1); + + for (i = 0; i < nb_events; i++) { + const struct lttcomm_event_extended_header *ext_comm = + (struct lttcomm_event_extended_header *) + comm_ext_at; + int probe_storage_req = 0; + + comm_ext_at += sizeof(*ext_comm); + comm_ext_at += ext_comm->filter_len; + comm_ext_at += ext_comm->nb_exclusions * + LTTNG_SYMBOL_NAME_LEN; + + if (ext_comm->userspace_probe_location_len) { + struct lttng_userspace_probe_location + *probe_location = NULL; + struct lttng_payload_view probe_location_view = lttng_payload_view_from_view( + &payload_view, + (const char *) comm_ext_at - + payload_view.buffer.data, + ext_comm->userspace_probe_location_len); + + if (!lttng_payload_view_is_valid(&probe_location_view)) { + ret = -LTTNG_ERR_PROBE_LOCATION_INVAL; + goto end; + } + + /* + * Create a temporary userspace probe location + * to determine the size needed by a "flattened" + * version of that same probe location. + */ + ret = lttng_userspace_probe_location_create_from_payload( + &probe_location_view, + &probe_location); + if (ret < 0) { + ret = -LTTNG_ERR_PROBE_LOCATION_INVAL; + goto end; + } + + ret = lttng_userspace_probe_location_flatten( + probe_location, NULL); + lttng_userspace_probe_location_destroy( + probe_location); + if (ret < 0) { + ret = -LTTNG_ERR_PROBE_LOCATION_INVAL; + goto end; + } + + probe_storage_req = ret; + comm_ext_at += ext_comm->userspace_probe_location_len; + } + + storage_req += sizeof(struct lttng_event_extended); + storage_req += ext_comm->filter_len; + storage_req += ext_comm->nb_exclusions * + LTTNG_SYMBOL_NAME_LEN; + /* Padding to ensure the flat probe is aligned. */ + storage_req = lttng_align_ceil(storage_req, sizeof(uint64_t)); + storage_req += probe_storage_req; + } + } + + lttng_dynamic_buffer_init(&listing); + /* + * We must ensure that "listing" is never resized so as to preserve + * the validity of the flattened objects. + */ + ret = lttng_dynamic_buffer_set_capacity(&listing, storage_req); + if (ret) { + ret = -LTTNG_ERR_NOMEM; + goto end; + } + + cmd_payload_view = lttng_buffer_view_from_dynamic_buffer( + &payload_copy.buffer, sizeof(*cmd_header), -1); + flat_events_view = lttng_buffer_view_from_view(&cmd_payload_view, 0, + nb_events * sizeof(struct lttng_event)); + ret = lttng_dynamic_buffer_append_view(&listing, &flat_events_view); + if (ret) { + ret = -LTTNG_ERR_NOMEM; + goto free_dynamic_buffer; + } + + ext_view = lttng_buffer_view_from_view(&cmd_payload_view, + nb_events * sizeof(struct lttng_event), -1); + comm_ext_at = ext_view.data; + + { + struct lttng_payload_view payload_copy_view = + lttng_payload_view_from_payload( + &payload_copy, 0, -1); + + for (i = 0; i < nb_events; i++) { + struct lttng_event *event = (typeof(event))( + listing.data + + (sizeof(struct lttng_event) * i)); + const struct lttcomm_event_extended_header *ext_comm = + (typeof(ext_comm)) comm_ext_at; + struct lttng_event_extended *event_extended = + (typeof(event_extended))(listing.data + + listing.size); + + /* Insert struct lttng_event_extended. */ + ret = lttng_dynamic_buffer_set_size(&listing, + listing.size + sizeof(*event_extended)); + if (ret) { + ret = -LTTNG_ERR_NOMEM; + goto free_dynamic_buffer; + } + event->extended.ptr = event_extended; + + comm_ext_at += sizeof(*ext_comm); + + /* Insert filter expression. */ + if (ext_comm->filter_len) { + event_extended->filter_expression = + listing.data + listing.size; + ret = lttng_dynamic_buffer_append(&listing, + comm_ext_at, + ext_comm->filter_len); + if (ret) { + ret = -LTTNG_ERR_NOMEM; + goto free_dynamic_buffer; + } + comm_ext_at += ext_comm->filter_len; + } + + /* Insert exclusions. */ + if (ext_comm->nb_exclusions) { + event_extended->exclusions.count = + ext_comm->nb_exclusions; + event_extended->exclusions.strings = + listing.data + listing.size; + + ret = lttng_dynamic_buffer_append(&listing, + comm_ext_at, + ext_comm->nb_exclusions * + LTTNG_SYMBOL_NAME_LEN); + if (ret) { + ret = -LTTNG_ERR_NOMEM; + goto free_dynamic_buffer; + } + comm_ext_at += ext_comm->nb_exclusions * + LTTNG_SYMBOL_NAME_LEN; + } + + /* Insert padding to align to 64-bits. */ + ret = lttng_dynamic_buffer_set_size(&listing, + lttng_align_ceil(listing.size, + sizeof(uint64_t))); + if (ret) { + ret = -LTTNG_ERR_NOMEM; + goto free_dynamic_buffer; + } + + /* Insert flattened userspace probe location. */ + if (ext_comm->userspace_probe_location_len) { + struct lttng_userspace_probe_location + *probe_location = NULL; + struct lttng_payload_view probe_location_view = lttng_payload_view_from_view( + &payload_copy_view, + (const char *) comm_ext_at - + payload_copy_view.buffer.data, + ext_comm->userspace_probe_location_len); + + if (!lttng_payload_view_is_valid(&probe_location_view)) { + ret = -LTTNG_ERR_PROBE_LOCATION_INVAL; + goto free_dynamic_buffer; + } + + ret = lttng_userspace_probe_location_create_from_payload( + &probe_location_view, + &probe_location); + if (ret < 0) { + ret = -LTTNG_ERR_PROBE_LOCATION_INVAL; + goto free_dynamic_buffer; + } + + event_extended->probe_location = (struct lttng_userspace_probe_location + *) (listing.data + + listing.size); + ret = lttng_userspace_probe_location_flatten( + probe_location, &listing); + lttng_userspace_probe_location_destroy( + probe_location); + if (ret < 0) { + ret = -LTTNG_ERR_PROBE_LOCATION_INVAL; + goto free_dynamic_buffer; + } + + comm_ext_at += ext_comm->userspace_probe_location_len; + } + } + } + + /* Don't reset listing buffer as we return its content. */ + *events = (struct lttng_event *) listing.data; + lttng_dynamic_buffer_init(&listing); + ret = (int) nb_events; +free_dynamic_buffer: + lttng_dynamic_buffer_reset(&listing); +end: + lttng_payload_reset(&payload); + lttng_payload_reset(&payload_copy); + return ret; +} + +/* + * Sets the tracing_group variable with name. + * This function allocates memory pointed to by tracing_group. + * On success, returns 0, on error, returns -1 (null name) or -ENOMEM. + */ +int lttng_set_tracing_group(const char *name) +{ + int ret = 0; + char *new_group; + + if (name == NULL) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + new_group = strdup(name); + if (!new_group) { + ret = -LTTNG_ERR_FATAL; + goto end; + } + + free(tracing_group); + tracing_group = new_group; + new_group = NULL; + +end: + return ret; +} + +int lttng_calibrate(struct lttng_handle *handle, + struct lttng_calibrate *calibrate) +{ + /* + * This command was removed in LTTng 2.9. + */ + return -LTTNG_ERR_UND; +} + +/* + * Set default channel attributes. + * If either or both of the arguments are null, attr content is zeroe'd. + */ +void lttng_channel_set_default_attr(struct lttng_domain *domain, + struct lttng_channel_attr *attr) +{ + struct lttng_channel_extended *extended; + + /* Safety check */ + if (attr == NULL || domain == NULL) { + return; + } + + extended = (struct lttng_channel_extended *) attr->extended.ptr; + memset(attr, 0, sizeof(struct lttng_channel_attr)); + + /* Same for all domains. */ + attr->overwrite = DEFAULT_CHANNEL_OVERWRITE; + attr->tracefile_size = DEFAULT_CHANNEL_TRACEFILE_SIZE; + attr->tracefile_count = DEFAULT_CHANNEL_TRACEFILE_COUNT; + + switch (domain->type) { + case LTTNG_DOMAIN_KERNEL: + attr->switch_timer_interval = + DEFAULT_KERNEL_CHANNEL_SWITCH_TIMER; + attr->read_timer_interval = DEFAULT_KERNEL_CHANNEL_READ_TIMER; + attr->subbuf_size = default_get_kernel_channel_subbuf_size(); + attr->num_subbuf = DEFAULT_KERNEL_CHANNEL_SUBBUF_NUM; + attr->output = DEFAULT_KERNEL_CHANNEL_OUTPUT; + if (extended) { + extended->monitor_timer_interval = + DEFAULT_KERNEL_CHANNEL_MONITOR_TIMER; + extended->blocking_timeout = + DEFAULT_KERNEL_CHANNEL_BLOCKING_TIMEOUT; + } + break; + case LTTNG_DOMAIN_UST: + switch (domain->buf_type) { + case LTTNG_BUFFER_PER_UID: + attr->subbuf_size = default_get_ust_uid_channel_subbuf_size(); + attr->num_subbuf = DEFAULT_UST_UID_CHANNEL_SUBBUF_NUM; + attr->output = DEFAULT_UST_UID_CHANNEL_OUTPUT; + attr->switch_timer_interval = + DEFAULT_UST_UID_CHANNEL_SWITCH_TIMER; + attr->read_timer_interval = + DEFAULT_UST_UID_CHANNEL_READ_TIMER; + if (extended) { + extended->monitor_timer_interval = + DEFAULT_UST_UID_CHANNEL_MONITOR_TIMER; + extended->blocking_timeout = + DEFAULT_UST_UID_CHANNEL_BLOCKING_TIMEOUT; + } + break; + case LTTNG_BUFFER_PER_PID: + default: + attr->subbuf_size = default_get_ust_pid_channel_subbuf_size(); + attr->num_subbuf = DEFAULT_UST_PID_CHANNEL_SUBBUF_NUM; + attr->output = DEFAULT_UST_PID_CHANNEL_OUTPUT; + attr->switch_timer_interval = + DEFAULT_UST_PID_CHANNEL_SWITCH_TIMER; + attr->read_timer_interval = + DEFAULT_UST_PID_CHANNEL_READ_TIMER; + if (extended) { + extended->monitor_timer_interval = + DEFAULT_UST_PID_CHANNEL_MONITOR_TIMER; + extended->blocking_timeout = + DEFAULT_UST_PID_CHANNEL_BLOCKING_TIMEOUT; + } + break; + } + default: + /* Default behavior: leave set to 0. */ + break; + } + + attr->extended.ptr = extended; +} + +int lttng_channel_get_discarded_event_count(struct lttng_channel *channel, + uint64_t *discarded_events) +{ + int ret = 0; + struct lttng_channel_extended *chan_ext; + + if (!channel || !discarded_events) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + chan_ext = (lttng_channel_extended *) channel->attr.extended.ptr; + if (!chan_ext) { + /* + * This can happen since the lttng_channel structure is + * used for other tasks where this pointer is never set. + */ + *discarded_events = 0; + goto end; + } + + *discarded_events = chan_ext->discarded_events; +end: + return ret; +} + +int lttng_channel_get_lost_packet_count(struct lttng_channel *channel, + uint64_t *lost_packets) +{ + int ret = 0; + struct lttng_channel_extended *chan_ext; + + if (!channel || !lost_packets) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + chan_ext = (lttng_channel_extended *) channel->attr.extended.ptr; + if (!chan_ext) { + /* + * This can happen since the lttng_channel structure is + * used for other tasks where this pointer is never set. + */ + *lost_packets = 0; + goto end; + } + + *lost_packets = chan_ext->lost_packets; +end: + return ret; +} + +int lttng_channel_get_monitor_timer_interval(struct lttng_channel *chan, + uint64_t *monitor_timer_interval) +{ + int ret = 0; + + if (!chan || !monitor_timer_interval) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + if (!chan->attr.extended.ptr) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + *monitor_timer_interval = ((struct lttng_channel_extended *) + chan->attr.extended.ptr)->monitor_timer_interval; +end: + return ret; +} + +int lttng_channel_set_monitor_timer_interval(struct lttng_channel *chan, + uint64_t monitor_timer_interval) +{ + int ret = 0; + + if (!chan || !chan->attr.extended.ptr) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + ((struct lttng_channel_extended *) + chan->attr.extended.ptr)->monitor_timer_interval = + monitor_timer_interval; +end: + return ret; +} + +int lttng_channel_get_blocking_timeout(struct lttng_channel *chan, + int64_t *blocking_timeout) +{ + int ret = 0; + + if (!chan || !blocking_timeout) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + if (!chan->attr.extended.ptr) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + *blocking_timeout = ((struct lttng_channel_extended *) + chan->attr.extended.ptr)->blocking_timeout; +end: + return ret; +} + +int lttng_channel_set_blocking_timeout(struct lttng_channel *chan, + int64_t blocking_timeout) +{ + int ret = 0; + int64_t msec_timeout; + + if (!chan || !chan->attr.extended.ptr) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + if (blocking_timeout < 0 && blocking_timeout != -1) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + /* + * LTTng-ust's use of poll() to implement this timeout mechanism forces + * us to accept a narrower range of values (msecs expressed as a signed + * 32-bit integer). + */ + msec_timeout = blocking_timeout / 1000; + if (msec_timeout != (int32_t) msec_timeout) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + ((struct lttng_channel_extended *) + chan->attr.extended.ptr)->blocking_timeout = + blocking_timeout; +end: + return ret; +} + +/* + * Check if session daemon is alive. + * + * Return 1 if alive or 0 if not. + * On error returns a negative value. + */ +int lttng_session_daemon_alive(void) +{ + int ret; + + ret = set_session_daemon_path(); + if (ret < 0) { + /* Error. */ + return ret; + } + + if (*sessiond_sock_path == '\0') { + /* + * No socket path set. Weird error which means the constructor + * was not called. + */ + abort(); + } + + ret = try_connect_sessiond(sessiond_sock_path); + if (ret < 0) { + /* Not alive. */ + return 0; + } + + /* Is alive. */ + return 1; +} + +/* + * Set URL for a consumer for a session and domain. + * + * Return 0 on success, else a negative value. + */ +int lttng_set_consumer_url(struct lttng_handle *handle, + const char *control_url, const char *data_url) +{ + int ret; + ssize_t size; + struct lttcomm_session_msg lsm; + struct lttng_uri *uris = NULL; + + if (handle == NULL || (control_url == NULL && data_url == NULL)) { + ret = -LTTNG_ERR_INVALID; + goto error; + } + + memset(&lsm, 0, sizeof(lsm)); + + lsm.cmd_type = LTTNG_SET_CONSUMER_URI; + + ret = lttng_strncpy(lsm.session.name, handle->session_name, + sizeof(lsm.session.name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto error; + } + + COPY_DOMAIN_PACKED(lsm.domain, handle->domain); + + size = uri_parse_str_urls(control_url, data_url, &uris); + if (size < 0) { + ret = -LTTNG_ERR_INVALID; + goto error; + } + + lsm.u.uri.size = size; + + ret = lttng_ctl_ask_sessiond_varlen_no_cmd_header(&lsm, uris, + sizeof(struct lttng_uri) * size, NULL); + + free(uris); +error: + return ret; +} + +/* + * [OBSOLETE] + */ +extern "C" +LTTNG_EXPORT int lttng_enable_consumer(struct lttng_handle *handle); +int lttng_enable_consumer(struct lttng_handle *handle) +{ + return -ENOSYS; +} + +/* + * [OBSOLETE] + */ +extern "C" +LTTNG_EXPORT int lttng_disable_consumer(struct lttng_handle *handle); +int lttng_disable_consumer(struct lttng_handle *handle) +{ + return -ENOSYS; +} + +/* + * [OBSOLETE] + */ +extern "C" +LTTNG_EXPORT int _lttng_create_session_ext(const char *name, const char *url, + const char *datetime); +int _lttng_create_session_ext(const char *name, const char *url, + const char *datetime) +{ + return -ENOSYS; +} + +/* + * For a given session name, this call checks if the data is ready to be read + * or is still being extracted by the consumer(s) hence not ready to be used by + * any readers. + */ +int lttng_data_pending(const char *session_name) +{ + int ret; + struct lttcomm_session_msg lsm; + uint8_t *pending = NULL; + + if (session_name == NULL) { + return -LTTNG_ERR_INVALID; + } + + memset(&lsm, 0, sizeof(lsm)); + lsm.cmd_type = LTTNG_DATA_PENDING; + + ret = lttng_strncpy(lsm.session.name, session_name, + sizeof(lsm.session.name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + ret = lttng_ctl_ask_sessiond(&lsm, (void **) &pending); + if (ret < 0) { + goto end; + } else if (ret != 1) { + /* Unexpected payload size */ + ret = -LTTNG_ERR_INVALID; + goto end; + } else if (!pending) { + /* Internal error. */ + ret = -LTTNG_ERR_UNK; + goto end; + } + + ret = (int) *pending; +end: + free(pending); + return ret; +} + +/* + * Regenerate the metadata for a session. + * Return 0 on success, a negative error code on error. + */ +int lttng_regenerate_metadata(const char *session_name) +{ + int ret; + struct lttcomm_session_msg lsm; + + if (!session_name) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + memset(&lsm, 0, sizeof(lsm)); + lsm.cmd_type = LTTNG_REGENERATE_METADATA; + + ret = lttng_strncpy(lsm.session.name, session_name, + sizeof(lsm.session.name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + ret = lttng_ctl_ask_sessiond(&lsm, NULL); + if (ret < 0) { + goto end; + } + + ret = 0; +end: + return ret; +} + +/* + * Deprecated, replaced by lttng_regenerate_metadata. + */ +int lttng_metadata_regenerate(const char *session_name) +{ + return lttng_regenerate_metadata(session_name); +} + +/* + * Regenerate the statedump of a session. + * Return 0 on success, a negative error code on error. + */ +int lttng_regenerate_statedump(const char *session_name) +{ + int ret; + struct lttcomm_session_msg lsm; + + if (!session_name) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + memset(&lsm, 0, sizeof(lsm)); + lsm.cmd_type = LTTNG_REGENERATE_STATEDUMP; + + ret = lttng_strncpy(lsm.session.name, session_name, + sizeof(lsm.session.name)); + if (ret) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + ret = lttng_ctl_ask_sessiond(&lsm, NULL); + if (ret < 0) { + goto end; + } + + ret = 0; +end: + return ret; +} + +static +int _lttng_register_trigger(struct lttng_trigger *trigger, const char *name, + bool generate_name) +{ + int ret; + struct lttcomm_session_msg lsm = { + .cmd_type = LTTNG_REGISTER_TRIGGER, + }; + lsm.u.trigger.is_trigger_anonymous = !name && !generate_name; + struct lttcomm_session_msg *message_lsm; + struct lttng_payload message; + struct lttng_payload reply; + struct lttng_trigger *reply_trigger = NULL; + enum lttng_domain_type domain_type; + const struct lttng_credentials user_creds = { + .uid = LTTNG_OPTIONAL_INIT_VALUE(geteuid()), + .gid = LTTNG_OPTIONAL_INIT_UNSET, + }; + const char *unused_trigger_name = NULL; + enum lttng_trigger_status trigger_status; + + lttng_payload_init(&message); + lttng_payload_init(&reply); + + if (!trigger) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + trigger_status = lttng_trigger_get_name(trigger, &unused_trigger_name); + if (trigger_status != LTTNG_TRIGGER_STATUS_UNSET) { + /* Re-using already registered trigger. */ + ret = -LTTNG_ERR_INVALID; + goto end; + } + + if (name) { + trigger_status = lttng_trigger_set_name(trigger, name); + if (trigger_status != LTTNG_TRIGGER_STATUS_OK) { + ret = -LTTNG_ERR_NOMEM; + goto end; + } + } + + if (!trigger->creds.uid.is_set) { + /* Use the client's credentials as the trigger credentials. */ + lttng_trigger_set_credentials(trigger, &user_creds); + } else { + /* + * Validate that either the current trigger credentials and the + * client credentials are identical or that the current user is + * root. The root user can register, unregister triggers for + * himself and other users. + * + * This check is also present on the sessiond side, using the + * credentials passed on the socket. These check are all + * "safety" checks. + */ + const struct lttng_credentials *trigger_creds = + lttng_trigger_get_credentials(trigger); + + if (!lttng_credentials_is_equal_uid(trigger_creds, &user_creds)) { + if (lttng_credentials_get_uid(&user_creds) != 0) { + ret = -LTTNG_ERR_EPERM; + goto end_unset_name; + } + } + } + + if (!lttng_trigger_validate(trigger)) { + ret = -LTTNG_ERR_INVALID_TRIGGER; + goto end_unset_name; + } + + domain_type = lttng_trigger_get_underlying_domain_type_restriction( + trigger); + + lsm.domain.type = domain_type; + + ret = lttng_dynamic_buffer_append(&message.buffer, &lsm, sizeof(lsm)); + if (ret) { + ret = -LTTNG_ERR_NOMEM; + goto end_unset_name; + } + + ret = lttng_trigger_serialize(trigger, &message); + if (ret < 0) { + ret = -LTTNG_ERR_UNK; + goto end_unset_name; + } + + /* + * This is needed to populate the trigger object size for the command + * header. + */ + message_lsm = (struct lttcomm_session_msg *) message.buffer.data; + + message_lsm->u.trigger.length = (uint32_t) message.buffer.size - sizeof(lsm); + + { + struct lttng_payload_view message_view = + lttng_payload_view_from_payload( + &message, 0, -1); + + message_lsm->fd_count = lttng_payload_view_get_fd_handle_count( + &message_view); + ret = lttng_ctl_ask_sessiond_payload(&message_view, &reply); + if (ret < 0) { + goto end_unset_name; + } + } + + { + struct lttng_payload_view reply_view = + lttng_payload_view_from_payload( + &reply, 0, reply.buffer.size); + + ret = lttng_trigger_create_from_payload( + &reply_view, &reply_trigger); + if (ret < 0) { + ret = -LTTNG_ERR_INVALID_PROTOCOL; + goto end_unset_name; + } + } + + if (name || generate_name) { + ret = lttng_trigger_assign_name(trigger, reply_trigger); + if (ret < 0) { + ret = -LTTNG_ERR_NOMEM; + goto end; + } + } + + ret = 0; + goto end; + +end_unset_name: + trigger_status = lttng_trigger_set_name(trigger, NULL); + if (trigger_status != LTTNG_TRIGGER_STATUS_OK) { + ret = -LTTNG_ERR_UNK; + } +end: + lttng_payload_reset(&message); + lttng_payload_reset(&reply); + lttng_trigger_destroy(reply_trigger); + return ret; +} + +int lttng_register_trigger(struct lttng_trigger *trigger) +{ + /* Register an anonymous trigger. */ + return _lttng_register_trigger(trigger, NULL, false); +} + +enum lttng_error_code lttng_register_trigger_with_name( + struct lttng_trigger *trigger, const char *name) +{ + const int ret = _lttng_register_trigger(trigger, name, false); + + return ret == 0 ? LTTNG_OK : (enum lttng_error_code) -ret; +} + +enum lttng_error_code lttng_register_trigger_with_automatic_name( + struct lttng_trigger *trigger) +{ + const int ret = _lttng_register_trigger(trigger, nullptr, true); + + return ret == 0 ? LTTNG_OK : (enum lttng_error_code) -ret; +} + +enum lttng_error_code lttng_error_query_execute( + const struct lttng_error_query *query, + const struct lttng_endpoint *endpoint, + struct lttng_error_query_results **results) +{ + int ret; + enum lttng_error_code ret_code; + struct lttcomm_session_msg lsm = { + .cmd_type = LTTNG_EXECUTE_ERROR_QUERY, + }; + struct lttng_payload message; + struct lttng_payload reply; + struct lttcomm_session_msg *message_lsm; + + lttng_payload_init(&message); + lttng_payload_init(&reply); + + if (!query || !results) { + ret_code = LTTNG_ERR_INVALID; + goto end; + } + + if (endpoint != lttng_session_daemon_command_endpoint) { + ret_code = LTTNG_ERR_INVALID_ERROR_QUERY_TARGET; + goto end; + } + + ret = lttng_dynamic_buffer_append(&message.buffer, &lsm, sizeof(lsm)); + if (ret) { + ret_code = LTTNG_ERR_NOMEM; + goto end; + } + + ret = lttng_error_query_serialize(query, &message); + if (ret) { + ret_code = LTTNG_ERR_UNK; + goto end; + } + + message_lsm = (struct lttcomm_session_msg *) message.buffer.data; + message_lsm->u.error_query.length = + (uint32_t) message.buffer.size - sizeof(lsm); + + { + struct lttng_payload_view message_view = + lttng_payload_view_from_payload( + &message, 0, -1); + + message_lsm->fd_count = lttng_payload_view_get_fd_handle_count( + &message_view); + ret = lttng_ctl_ask_sessiond_payload(&message_view, &reply); + if (ret < 0) { + ret_code =(lttng_error_code) -ret; + goto end; + } + } + + { + ssize_t reply_create_ret; + struct lttng_payload_view reply_view = + lttng_payload_view_from_payload( + &reply, 0, reply.buffer.size); + + reply_create_ret = lttng_error_query_results_create_from_payload( + &reply_view, results); + if (reply_create_ret < 0) { + ret_code = LTTNG_ERR_INVALID_PROTOCOL; + goto end; + } + } + + ret_code = LTTNG_OK; +end: + lttng_payload_reset(&message); + lttng_payload_reset(&reply); + return ret_code; +} + +int lttng_unregister_trigger(const struct lttng_trigger *trigger) +{ + int ret; + struct lttcomm_session_msg lsm; + struct lttcomm_session_msg *message_lsm; + struct lttng_payload message; + struct lttng_payload reply; + struct lttng_trigger *copy = NULL; + const struct lttng_credentials user_creds = { + .uid = LTTNG_OPTIONAL_INIT_VALUE(geteuid()), + .gid = LTTNG_OPTIONAL_INIT_UNSET, + }; + + lttng_payload_init(&message); + lttng_payload_init(&reply); + + if (!trigger) { + ret = -LTTNG_ERR_INVALID; + goto end; + } + + copy = lttng_trigger_copy(trigger); + if (!copy) { + ret = -LTTNG_ERR_UNK; + goto end; + } + + if (!copy->creds.uid.is_set) { + /* Use the client credentials as the trigger credentials */ + lttng_trigger_set_credentials(copy, &user_creds); + } else { + /* + * Validate that either the current trigger credentials and the + * client credentials are identical or that the current user is + * root. The root user can register, unregister triggers for + * himself and other users. + * + * This check is also present on the sessiond side, using the + * credentials passed on the socket. These check are all + * "safety" checks. + */ + const struct lttng_credentials *trigger_creds = + lttng_trigger_get_credentials(copy); + if (!lttng_credentials_is_equal_uid(trigger_creds, &user_creds)) { + if (lttng_credentials_get_uid(&user_creds) != 0) { + ret = -LTTNG_ERR_EPERM; + goto end; + } + } + } + + if (!lttng_trigger_validate(copy)) { + ret = -LTTNG_ERR_INVALID_TRIGGER; + goto end; + } + + memset(&lsm, 0, sizeof(lsm)); + lsm.cmd_type = LTTNG_UNREGISTER_TRIGGER; + + ret = lttng_dynamic_buffer_append(&message.buffer, &lsm, sizeof(lsm)); + if (ret) { + ret = -LTTNG_ERR_NOMEM; + goto end; + } + + ret = lttng_trigger_serialize(copy, &message); + if (ret < 0) { + ret = -LTTNG_ERR_UNK; + goto end; + } + + /* + * This is needed to populate the trigger object size for the command + * header and number of fds sent. + */ + message_lsm = (struct lttcomm_session_msg *) message.buffer.data; + + message_lsm->u.trigger.length = (uint32_t) message.buffer.size - sizeof(lsm); + + { + struct lttng_payload_view message_view = + lttng_payload_view_from_payload( + &message, 0, -1); + + /* + * Update the message header with the number of fd that will be + * sent. + */ + message_lsm->fd_count = lttng_payload_view_get_fd_handle_count( + &message_view); + + ret = lttng_ctl_ask_sessiond_payload(&message_view, &reply); + if (ret < 0) { + goto end; + } + } + + ret = 0; +end: + lttng_trigger_destroy(copy); + lttng_payload_reset(&message); + lttng_payload_reset(&reply); + return ret; +} + +/* + * Ask the session daemon for all registered triggers for the current user. + * + * Allocates and return an lttng_triggers set. + * On error, returns a suitable lttng_error_code. + */ +enum lttng_error_code lttng_list_triggers(struct lttng_triggers **triggers) +{ + int ret; + enum lttng_error_code ret_code = LTTNG_OK; + struct lttcomm_session_msg lsm = { .cmd_type = LTTNG_LIST_TRIGGERS }; + struct lttng_triggers *local_triggers = NULL; + struct lttng_payload reply; + struct lttng_payload_view lsm_view = + lttng_payload_view_init_from_buffer( + (const char *) &lsm, 0, sizeof(lsm)); + + lttng_payload_init(&reply); + + ret = lttng_ctl_ask_sessiond_payload(&lsm_view, &reply); + if (ret < 0) { + ret_code = (enum lttng_error_code) -ret; + goto end; + } + + { + struct lttng_payload_view reply_view = + lttng_payload_view_from_payload( + &reply, 0, reply.buffer.size); + + ret = lttng_triggers_create_from_payload( + &reply_view, &local_triggers); + if (ret < 0) { + ret_code = LTTNG_ERR_FATAL; + goto end; + } + } + + *triggers = local_triggers; + local_triggers = NULL; +end: + lttng_payload_reset(&reply); + lttng_triggers_destroy(local_triggers); + return ret_code; +} + +/* + * lib constructor. + */ +static void __attribute__((constructor)) init(void) +{ + /* Set default session group */ + lttng_set_tracing_group(DEFAULT_TRACING_GROUP); +} + +/* + * lib destructor. + */ +static void __attribute__((destructor)) lttng_ctl_exit(void) +{ + free(tracing_group); +}