Add lttng_event_get_filter_string() to liblttng-ctl
[lttng-tools.git] / src / bin / lttng-sessiond / cmd.c
index a6ce344a483d11642bf751aae9fad1565aa46afd..800859b8e55437919af0eba63d3278652eba1bed 100644 (file)
@@ -1,5 +1,6 @@
 /*
  * Copyright (C) 2012 - David Goulet <dgoulet@efficios.com>
+ * Copyright (C) 2016 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License, version 2 only, as
  * Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  */
 
-#define _GNU_SOURCE
 #define _LGPL_SOURCE
 #include <assert.h>
-#include <string.h>
 #include <inttypes.h>
 #include <urcu/list.h>
 #include <urcu/uatomic.h>
@@ -28,6 +27,7 @@
 #include <common/sessiond-comm/sessiond-comm.h>
 #include <common/relayd/relayd.h>
 #include <common/utils.h>
+#include <common/compat/string.h>
 
 #include "channel.h"
 #include "consumer.h"
@@ -38,6 +38,7 @@
 #include "lttng-sessiond.h"
 #include "utils.h"
 #include "syscall.h"
+#include "agent.h"
 
 #include "cmd.h"
 
 static pthread_mutex_t relayd_net_seq_idx_lock = PTHREAD_MUTEX_INITIALIZER;
 static uint64_t relayd_net_seq_idx;
 
+static int validate_event_name(const char *);
+static int validate_ust_event_name(const char *);
+static int cmd_enable_event_internal(struct ltt_session *session,
+               struct lttng_domain *domain,
+               char *channel_name, struct lttng_event *event,
+               char *filter_expression,
+               struct lttng_filter_bytecode *filter,
+               struct lttng_event_exclusion *exclusion,
+               int wpipe);
+
 /*
  * Create a session path used by list_lttng_sessions for the case that the
  * session consumer is on the network.
@@ -131,8 +142,8 @@ error:
 /*
  * Fill lttng_channel array of all channels.
  */
-static void list_lttng_channels(int domain, struct ltt_session *session,
-               struct lttng_channel *channels)
+static void list_lttng_channels(enum lttng_domain_type domain,
+               struct ltt_session *session, struct lttng_channel *channels)
 {
        int i = 0;
        struct ltt_kernel_channel *kchan;
@@ -187,19 +198,48 @@ static void list_lttng_channels(int domain, struct ltt_session *session,
        }
 }
 
+static void increment_extended_len(const char *filter_expression,
+               size_t *extended_len)
+{
+       *extended_len += sizeof(struct lttcomm_event_extended_header);
+
+       if (filter_expression) {
+               *extended_len += strlen(filter_expression) + 1;
+       }
+}
+
+static void append_extended_info(const char *filter_expression,
+               void **extended_at)
+{
+       struct lttcomm_event_extended_header extended_header;
+       size_t filter_len = 0;
+
+       if (filter_expression) {
+               filter_len = strlen(filter_expression) + 1;
+       }
+
+       extended_header.filter_len = filter_len;
+       memcpy(*extended_at, &extended_header, sizeof(extended_header));
+       *extended_at += sizeof(extended_header);
+       memcpy(*extended_at, filter_expression, filter_len);
+       *extended_at += filter_len;
+}
+
 /*
  * Create a list of agent domain events.
  *
  * Return number of events in list on success or else a negative value.
  */
 static int list_lttng_agent_events(struct agent *agt,
-               struct lttng_event **events)
+               struct lttng_event **events, size_t *total_size)
 {
        int i = 0, ret = 0;
        unsigned int nb_event = 0;
        struct agent_event *event;
        struct lttng_event *tmp_events;
        struct lttng_ht_iter iter;
+       size_t extended_len = 0;
+       void *extended_at;
 
        assert(agt);
        assert(events);
@@ -211,24 +251,45 @@ static int list_lttng_agent_events(struct agent *agt,
        rcu_read_unlock();
        if (nb_event == 0) {
                ret = nb_event;
+               *total_size = 0;
                goto error;
        }
 
-       tmp_events = zmalloc(nb_event * sizeof(*tmp_events));
+       /* Compute required extended infos size */
+       extended_len = nb_event * sizeof(struct lttcomm_event_extended_header);
+
+       /*
+        * This is only valid because the commands which add events are
+        * processed in the same thread as the listing.
+        */
+       rcu_read_lock();
+       cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
+               increment_extended_len(event->filter_expression, &extended_len);
+       }
+       rcu_read_unlock();
+
+       *total_size = nb_event * sizeof(*tmp_events) + extended_len;
+       tmp_events = zmalloc(*total_size);
        if (!tmp_events) {
                PERROR("zmalloc agent events session");
                ret = -LTTNG_ERR_FATAL;
                goto error;
        }
 
+       extended_at = ((uint8_t *) tmp_events) +
+               nb_event * sizeof(struct lttng_event);
+
        rcu_read_lock();
        cds_lfht_for_each_entry(agt->events->ht, &iter.iter, event, node.node) {
                strncpy(tmp_events[i].name, event->name, sizeof(tmp_events[i].name));
                tmp_events[i].name[sizeof(tmp_events[i].name) - 1] = '\0';
                tmp_events[i].enabled = event->enabled;
-               tmp_events[i].loglevel = event->loglevel;
+               tmp_events[i].loglevel = event->loglevel_value;
                tmp_events[i].loglevel_type = event->loglevel_type;
                i++;
+
+               /* Append extended info */
+               append_extended_info(event->filter_expression, &extended_at);
        }
        rcu_read_unlock();
 
@@ -244,7 +305,8 @@ error:
  * Create a list of ust global domain events.
  */
 static int list_lttng_ust_global_events(char *channel_name,
-               struct ltt_ust_domain_global *ust_global, struct lttng_event **events)
+               struct ltt_ust_domain_global *ust_global,
+               struct lttng_event **events, size_t *total_size)
 {
        int i = 0, ret = 0;
        unsigned int nb_event = 0;
@@ -253,6 +315,8 @@ static int list_lttng_ust_global_events(char *channel_name,
        struct ltt_ust_channel *uchan;
        struct ltt_ust_event *uevent;
        struct lttng_event *tmp;
+       size_t extended_len = 0;
+       void *extended_at;
 
        DBG("Listing UST global events for channel %s", channel_name);
 
@@ -262,27 +326,51 @@ static int list_lttng_ust_global_events(char *channel_name,
        node = lttng_ht_iter_get_node_str(&iter);
        if (node == NULL) {
                ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
-               goto error;
+               goto end;
        }
 
        uchan = caa_container_of(&node->node, struct ltt_ust_channel, node.node);
 
-       nb_event += lttng_ht_get_count(uchan->events);
-
+       nb_event = lttng_ht_get_count(uchan->events);
        if (nb_event == 0) {
                ret = nb_event;
-               goto error;
+               *total_size = 0;
+               goto end;
        }
 
        DBG3("Listing UST global %d events", nb_event);
 
-       tmp = zmalloc(nb_event * sizeof(struct lttng_event));
+       /* Compute required extended infos size */
+       cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
+               if (uevent->internal) {
+                       nb_event--;
+                       continue;
+               }
+
+               increment_extended_len(uevent->filter_expression,
+                       &extended_len);
+       }
+       if (nb_event == 0) {
+               /* All events are internal, skip. */
+               ret = 0;
+               *total_size = 0;
+               goto end;
+       }
+
+       *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
+       tmp = zmalloc(*total_size);
        if (tmp == NULL) {
                ret = LTTNG_ERR_FATAL;
                goto error;
        }
 
+       extended_at = ((uint8_t *) tmp) + nb_event * sizeof(struct lttng_event);
+
        cds_lfht_for_each_entry(uchan->events->ht, &iter.iter, uevent, node.node) {
+               if (uevent->internal) {
+                       /* This event should remain hidden from clients */
+                       continue;
+               }
                strncpy(tmp[i].name, uevent->attr.name, LTTNG_SYMBOL_NAME_LEN);
                tmp[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
                tmp[i].enabled = uevent->enabled;
@@ -318,12 +406,14 @@ static int list_lttng_ust_global_events(char *channel_name,
                        tmp[i].exclusion = 1;
                }
                i++;
+
+               /* Append extended info */
+               append_extended_info(uevent->filter_expression, &extended_at);
        }
 
        ret = nb_event;
        *events = tmp;
-
-error:
+end:
        rcu_read_unlock();
        return ret;
 }
@@ -332,12 +422,15 @@ error:
  * Fill lttng_event array of all kernel events in the channel.
  */
 static int list_lttng_kernel_events(char *channel_name,
-               struct ltt_kernel_session *kernel_session, struct lttng_event **events)
+               struct ltt_kernel_session *kernel_session,
+               struct lttng_event **events, size_t *total_size)
 {
        int i = 0, ret;
        unsigned int nb_event;
        struct ltt_kernel_event *event;
        struct ltt_kernel_channel *kchan;
+       size_t extended_len = 0;
+       void *extended_at;
 
        kchan = trace_kernel_get_channel_by_name(channel_name, kernel_session);
        if (kchan == NULL) {
@@ -350,21 +443,33 @@ static int list_lttng_kernel_events(char *channel_name,
        DBG("Listing events for channel %s", kchan->channel->name);
 
        if (nb_event == 0) {
+               *total_size = 0;
                *events = NULL;
                goto syscall;
        }
 
-       *events = zmalloc(nb_event * sizeof(struct lttng_event));
+       /* Compute required extended infos size */
+       cds_list_for_each_entry(event, &kchan->events_list.head, list) {
+               increment_extended_len(event->filter_expression, &extended_len);
+       }
+
+       *total_size = nb_event * sizeof(struct lttng_event) + extended_len;
+       *events = zmalloc(*total_size);
        if (*events == NULL) {
                ret = LTTNG_ERR_FATAL;
                goto error;
        }
 
+       extended_at = ((uint8_t *) events) +
+               nb_event * sizeof(struct lttng_event);
+
        /* Kernel channels */
        cds_list_for_each_entry(event, &kchan->events_list.head , list) {
                strncpy((*events)[i].name, event->event->name, LTTNG_SYMBOL_NAME_LEN);
                (*events)[i].name[LTTNG_SYMBOL_NAME_LEN - 1] = '\0';
                (*events)[i].enabled = event->enabled;
+               (*events)[i].filter =
+                               (unsigned char) !!event->filter_expression;
 
                switch (event->event->instrumentation) {
                case LTTNG_KERNEL_TRACEPOINT:
@@ -396,6 +501,9 @@ static int list_lttng_kernel_events(char *channel_name,
                        break;
                }
                i++;
+
+               /* Append extended info */
+               append_extended_info(event->filter_expression, &extended_at);
        }
 
 syscall:
@@ -423,7 +531,8 @@ error:
  * domain adding the default trace directory.
  */
 static int add_uri_to_consumer(struct consumer_output *consumer,
-               struct lttng_uri *uri, int domain, const char *session_name)
+               struct lttng_uri *uri, enum lttng_domain_type domain,
+               const char *session_name)
 {
        int ret = LTTNG_OK;
        const char *default_trace_dir;
@@ -620,8 +729,9 @@ error:
 /*
  * Connect to the relayd using URI and send the socket to the right consumer.
  */
-static int send_consumer_relayd_socket(int domain, unsigned int session_id,
-               struct lttng_uri *relayd_uri, struct consumer_output *consumer,
+static int send_consumer_relayd_socket(enum lttng_domain_type domain,
+               unsigned int session_id, struct lttng_uri *relayd_uri,
+               struct consumer_output *consumer,
                struct consumer_socket *consumer_sock,
                char *session_name, char *hostname, int session_live_timer)
 {
@@ -691,9 +801,10 @@ error:
  * helper function to facilitate sending the information to the consumer for a
  * session.
  */
-static int send_consumer_relayd_sockets(int domain, unsigned int session_id,
-               struct consumer_output *consumer, struct consumer_socket *sock,
-               char *session_name, char *hostname, int session_live_timer)
+static int send_consumer_relayd_sockets(enum lttng_domain_type domain,
+               unsigned int session_id, struct consumer_output *consumer,
+               struct consumer_socket *sock, char *session_name,
+               char *hostname, int session_live_timer)
 {
        int ret = LTTNG_OK;
 
@@ -856,8 +967,8 @@ error:
 /*
  * Command LTTNG_DISABLE_CHANNEL processed by the client thread.
  */
-int cmd_disable_channel(struct ltt_session *session, int domain,
-               char *channel_name)
+int cmd_disable_channel(struct ltt_session *session,
+               enum lttng_domain_type domain, char *channel_name)
 {
        int ret;
        struct ltt_ust_session *usess;
@@ -914,7 +1025,8 @@ error:
  *
  * Called with session lock held.
  */
-int cmd_track_pid(struct ltt_session *session, int domain, int pid)
+int cmd_track_pid(struct ltt_session *session, enum lttng_domain_type domain,
+               int pid)
 {
        int ret;
 
@@ -964,7 +1076,8 @@ error:
  *
  * Called with session lock held.
  */
-int cmd_untrack_pid(struct ltt_session *session, int domain, int pid)
+int cmd_untrack_pid(struct ltt_session *session, enum lttng_domain_type domain,
+               int pid)
 {
        int ret;
 
@@ -1026,7 +1139,7 @@ int cmd_enable_channel(struct ltt_session *session,
        assert(attr);
        assert(domain);
 
-       len = strnlen(attr->name, sizeof(attr->name));
+       len = lttng_strnlen(attr->name, sizeof(attr->name));
 
        /* Validate channel name */
        if (attr->name[0] == '.' ||
@@ -1092,9 +1205,40 @@ int cmd_enable_channel(struct ltt_session *session,
                break;
        }
        case LTTNG_DOMAIN_UST:
+       case LTTNG_DOMAIN_JUL:
+       case LTTNG_DOMAIN_LOG4J:
+       case LTTNG_DOMAIN_PYTHON:
        {
                struct ltt_ust_channel *uchan;
 
+               /*
+                * FIXME
+                *
+                * Current agent implementation limitations force us to allow
+                * only one channel at once in "agent" subdomains. Each
+                * subdomain has a default channel name which must be strictly
+                * adhered to.
+                */
+               if (domain->type == LTTNG_DOMAIN_JUL) {
+                       if (strncmp(attr->name, DEFAULT_JUL_CHANNEL_NAME,
+                                       LTTNG_SYMBOL_NAME_LEN)) {
+                               ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
+                               goto error;
+                       }
+               } else if (domain->type == LTTNG_DOMAIN_LOG4J) {
+                       if (strncmp(attr->name, DEFAULT_LOG4J_CHANNEL_NAME,
+                                       LTTNG_SYMBOL_NAME_LEN)) {
+                               ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
+                               goto error;
+                       }
+               } else if (domain->type == LTTNG_DOMAIN_PYTHON) {
+                       if (strncmp(attr->name, DEFAULT_PYTHON_CHANNEL_NAME,
+                                       LTTNG_SYMBOL_NAME_LEN)) {
+                               ret = LTTNG_ERR_INVALID_CHANNEL_NAME;
+                               goto error;
+                       }
+               }
+
                chan_ht = usess->domain_global.channels;
 
                uchan = trace_ust_find_channel_by_name(chan_ht, attr->name);
@@ -1122,8 +1266,8 @@ end:
 /*
  * Command LTTNG_DISABLE_EVENT processed by the client thread.
  */
-int cmd_disable_event(struct ltt_session *session, int domain,
-               char *channel_name,
+int cmd_disable_event(struct ltt_session *session,
+               enum lttng_domain_type domain, char *channel_name,
                struct lttng_event *event)
 {
        int ret;
@@ -1132,11 +1276,16 @@ int cmd_disable_event(struct ltt_session *session, int domain,
        DBG("Disable event command for event \'%s\'", event->name);
 
        event_name = event->name;
+       if (validate_event_name(event_name)) {
+               ret = LTTNG_ERR_INVALID_EVENT_NAME;
+               goto error;
+       }
 
        /* Error out on unhandled search criteria */
        if (event->loglevel_type || event->loglevel != -1 || event->enabled
                        || event->pid || event->filter || event->exclusion) {
-               return LTTNG_ERR_UNK;
+               ret = LTTNG_ERR_UNK;
+               goto error;
        }
 
        rcu_read_lock();
@@ -1156,46 +1305,36 @@ int cmd_disable_event(struct ltt_session *session, int domain,
                 */
                if (ksess->has_non_default_channel && channel_name[0] == '\0') {
                        ret = LTTNG_ERR_NEED_CHANNEL_NAME;
-                       goto error;
+                       goto error_unlock;
                }
 
                kchan = trace_kernel_get_channel_by_name(channel_name, ksess);
                if (kchan == NULL) {
                        ret = LTTNG_ERR_KERN_CHAN_NOT_FOUND;
-                       goto error;
+                       goto error_unlock;
                }
 
                switch (event->type) {
                case LTTNG_EVENT_ALL:
-                       ret = event_kernel_disable_event_all(kchan);
-                       if (ret != LTTNG_OK) {
-                               goto error;
-                       }
-                       break;
-               case LTTNG_EVENT_TRACEPOINT:    /* fall-through */
+               case LTTNG_EVENT_TRACEPOINT:
                case LTTNG_EVENT_SYSCALL:
-                       if (!strcmp(event_name, "*")) {
-                               ret = event_kernel_disable_event_type(kchan,
-                                       event->type);
+               case LTTNG_EVENT_PROBE:
+               case LTTNG_EVENT_FUNCTION:
+               case LTTNG_EVENT_FUNCTION_ENTRY:/* fall-through */
+                       if (event_name[0] == '\0') {
+                               ret = event_kernel_disable_event(kchan,
+                                       NULL, event->type);
                        } else {
                                ret = event_kernel_disable_event(kchan,
-                                       event_name);
+                                       event_name, event->type);
                        }
                        if (ret != LTTNG_OK) {
-                               goto error;
-                       }
-                       break;
-               case LTTNG_EVENT_PROBE:
-               case LTTNG_EVENT_FUNCTION:
-               case LTTNG_EVENT_FUNCTION_ENTRY:
-                       ret = event_kernel_disable_event(kchan, event_name);
-                       if (ret != LTTNG_OK) {
-                               goto error;
+                               goto error_unlock;
                        }
                        break;
                default:
                        ret = LTTNG_ERR_UNK;
-                       goto error;
+                       goto error_unlock;
                }
 
                kernel_wait_quiescent(kernel_tracer_fd);
@@ -1208,33 +1347,47 @@ int cmd_disable_event(struct ltt_session *session, int domain,
 
                usess = session->ust_session;
 
+               if (validate_ust_event_name(event_name)) {
+                       ret = LTTNG_ERR_INVALID_EVENT_NAME;
+                       goto error_unlock;
+               }
+
                /*
                 * If a non-default channel has been created in the
-                * session, explicitely require that -c chan_name needs
+                * session, explicitly require that -c chan_name needs
                 * to be provided.
                 */
                if (usess->has_non_default_channel && channel_name[0] == '\0') {
                        ret = LTTNG_ERR_NEED_CHANNEL_NAME;
-                       goto error;
+                       goto error_unlock;
                }
 
                uchan = trace_ust_find_channel_by_name(usess->domain_global.channels,
                                channel_name);
                if (uchan == NULL) {
                        ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
-                       goto error;
+                       goto error_unlock;
                }
 
                switch (event->type) {
                case LTTNG_EVENT_ALL:
-                       ret = event_ust_disable_tracepoint(usess, uchan, event_name);
+                       /*
+                        * An empty event name means that everything
+                        * should be disabled.
+                        */
+                       if (event->name[0] == '\0') {
+                               ret = event_ust_disable_all_tracepoints(usess, uchan);
+                       } else {
+                               ret = event_ust_disable_tracepoint(usess, uchan,
+                                               event_name);
+                       }
                        if (ret != LTTNG_OK) {
-                               goto error;
+                               goto error_unlock;
                        }
                        break;
                default:
                        ret = LTTNG_ERR_UNK;
-                       goto error;
+                       goto error_unlock;
                }
 
                DBG3("Disable UST event %s in channel %s completed", event_name,
@@ -1255,45 +1408,55 @@ int cmd_disable_event(struct ltt_session *session, int domain,
                        break;
                default:
                        ret = LTTNG_ERR_UNK;
-                       goto error;
+                       goto error_unlock;
                }
 
                agt = trace_ust_find_agent(usess, domain);
                if (!agt) {
                        ret = -LTTNG_ERR_UST_EVENT_NOT_FOUND;
-                       goto error;
+                       goto error_unlock;
                }
-               /* The wild card * means that everything should be disabled. */
-               if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
+               /*
+                * An empty event name means that everything
+                * should be disabled.
+                */
+               if (event->name[0] == '\0') {
                        ret = event_agent_disable_all(usess, agt);
                } else {
                        ret = event_agent_disable(usess, agt, event_name);
                }
                if (ret != LTTNG_OK) {
-                       goto error;
+                       goto error_unlock;
                }
 
                break;
        }
        default:
                ret = LTTNG_ERR_UND;
-               goto error;
+               goto error_unlock;
        }
 
        ret = LTTNG_OK;
 
-error:
+error_unlock:
        rcu_read_unlock();
+error:
        return ret;
 }
 
 /*
  * Command LTTNG_ADD_CONTEXT processed by the client thread.
  */
-int cmd_add_context(struct ltt_session *session, int domain,
+int cmd_add_context(struct ltt_session *session, enum lttng_domain_type domain,
                char *channel_name, struct lttng_event_context *ctx, int kwpipe)
 {
        int ret, chan_kern_created = 0, chan_ust_created = 0;
+       char *app_ctx_provider_name = NULL, *app_ctx_name = NULL;
+
+       if (ctx->ctx == LTTNG_EVENT_CONTEXT_APP_CONTEXT) {
+               app_ctx_provider_name = ctx->u.app_ctx.provider_name;
+               app_ctx_name = ctx->u.app_ctx.ctx_name;
+       }
 
        switch (domain) {
        case LTTNG_DOMAIN_KERNEL:
@@ -1313,6 +1476,29 @@ int cmd_add_context(struct ltt_session *session, int domain,
                        goto error;
                }
                break;
+       case LTTNG_DOMAIN_JUL:
+       case LTTNG_DOMAIN_LOG4J:
+       {
+               /*
+                * Validate channel name.
+                * If no channel name is given and the domain is JUL or LOG4J,
+                * set it to the appropriate domain-specific channel name. If
+                * a name is provided but does not match the expexted channel
+                * name, return an error.
+                */
+               if (domain == LTTNG_DOMAIN_JUL && *channel_name &&
+                               strcmp(channel_name,
+                               DEFAULT_JUL_CHANNEL_NAME)) {
+                       ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
+                       goto error;
+               } else if (domain == LTTNG_DOMAIN_LOG4J && *channel_name &&
+                               strcmp(channel_name,
+                               DEFAULT_LOG4J_CHANNEL_NAME)) {
+                       ret = LTTNG_ERR_UST_CHAN_NOT_FOUND;
+                       goto error;
+               }
+               /* break is _not_ missing here. */
+       }
        case LTTNG_DOMAIN_UST:
        {
                struct ltt_ust_session *usess = session->ust_session;
@@ -1340,6 +1526,10 @@ int cmd_add_context(struct ltt_session *session, int domain,
                }
 
                ret = context_ust_add(usess, domain, ctx, channel_name);
+               free(app_ctx_provider_name);
+               free(app_ctx_name);
+               app_ctx_name = NULL;
+               app_ctx_provider_name = NULL;
                if (ret != LTTNG_OK) {
                        goto error;
                }
@@ -1350,7 +1540,8 @@ int cmd_add_context(struct ltt_session *session, int domain,
                goto error;
        }
 
-       return LTTNG_OK;
+       ret = LTTNG_OK;
+       goto end;
 
 error:
        if (chan_kern_created) {
@@ -1374,6 +1565,9 @@ error:
                                uchan);
                trace_ust_destroy_channel(uchan);
        }
+end:
+       free(app_ctx_provider_name);
+       free(app_ctx_name);
        return ret;
 }
 
@@ -1382,6 +1576,7 @@ static int validate_event_name(const char *name)
        int ret = 0;
        const char *c = name;
        const char *event_name_end = c + LTTNG_SYMBOL_NAME_LEN;
+       bool null_terminated = false;
 
        /*
         * Make sure that unescaped wildcards are only used as the last
@@ -1390,6 +1585,7 @@ static int validate_event_name(const char *name)
        while (c < event_name_end) {
                switch (*c) {
                case '\0':
+                       null_terminated = true;
                        goto end;
                case '\\':
                        c++;
@@ -1405,20 +1601,57 @@ static int validate_event_name(const char *name)
                }
                c++;
        }
+end:
+       if (!ret && !null_terminated) {
+               ret = LTTNG_ERR_INVALID_EVENT_NAME;
+       }
+       return ret;
+}
+
+static inline bool name_starts_with(const char *name, const char *prefix)
+{
+       const size_t max_cmp_len = min(strlen(prefix), LTTNG_SYMBOL_NAME_LEN);
+
+       return !strncmp(name, prefix, max_cmp_len);
+}
+
+/* Perform userspace-specific event name validation */
+static int validate_ust_event_name(const char *name)
+{
+       int ret = 0;
+
+       if (!name) {
+               ret = -1;
+               goto end;
+       }
+
+       /*
+        * Check name against all internal UST event component namespaces used
+        * by the agents.
+        */
+       if (name_starts_with(name, DEFAULT_JUL_EVENT_COMPONENT) ||
+               name_starts_with(name, DEFAULT_LOG4J_EVENT_COMPONENT) ||
+               name_starts_with(name, DEFAULT_PYTHON_EVENT_COMPONENT)) {
+               ret = -1;
+       }
+
 end:
        return ret;
 }
 
 /*
- * Command LTTNG_ENABLE_EVENT processed by the client thread.
- * We own filter, exclusion, and filter_expression.
+ * Internal version of cmd_enable_event() with a supplemental
+ * "internal_event" flag which is used to enable internal events which should
+ * be hidden from clients. Such events are used in the agent implementation to
+ * enable the events through which all "agent" events are funeled.
  */
-int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
+static int _cmd_enable_event(struct ltt_session *session,
+               struct lttng_domain *domain,
                char *channel_name, struct lttng_event *event,
                char *filter_expression,
                struct lttng_filter_bytecode *filter,
                struct lttng_event_exclusion *exclusion,
-               int wpipe)
+               int wpipe, bool internal_event)
 {
        int ret, channel_created = 0;
        struct lttng_channel *attr;
@@ -1427,15 +1660,18 @@ int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
        assert(event);
        assert(channel_name);
 
+       /* If we have a filter, we must have its filter expression */
+       assert(!(!!filter_expression ^ !!filter));
+
        DBG("Enable event command for event \'%s\'", event->name);
 
+       rcu_read_lock();
+
        ret = validate_event_name(event->name);
        if (ret) {
                goto error;
        }
 
-       rcu_read_lock();
-
        switch (domain->type) {
        case LTTNG_DOMAIN_KERNEL:
        {
@@ -1527,9 +1763,10 @@ int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
                        event->type = LTTNG_EVENT_SYSCALL;      /* Hack */
                        ret = event_kernel_enable_event(kchan, event,
                                filter_expression_a, filter_a);
+                       /* We have passed ownership */
+                       filter_expression_a = NULL;
+                       filter_a = NULL;
                        if (ret != LTTNG_OK) {
-                               free(filter_expression_a);
-                               free(filter_a);
                                goto error;
                        }
                        break;
@@ -1612,14 +1849,42 @@ int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
                        assert(uchan);
                }
 
+               if (uchan->domain != LTTNG_DOMAIN_UST && !internal_event) {
+                       /*
+                        * Don't allow users to add UST events to channels which
+                        * are assigned to a userspace subdomain (JUL, Log4J,
+                        * Python, etc.).
+                        */
+                       ret = LTTNG_ERR_INVALID_CHANNEL_DOMAIN;
+                       goto error;
+               }
+
+               if (!internal_event) {
+                       /*
+                        * Ensure the event name is not reserved for internal
+                        * use.
+                        */
+                       ret = validate_ust_event_name(event->name);
+                       if (ret) {
+                               WARN("Userspace event name %s failed validation.",
+                                               event->name ?
+                                               event->name : "NULL");
+                               ret = LTTNG_ERR_INVALID_EVENT_NAME;
+                               goto error;
+                       }
+               }
+
                /* At this point, the session and channel exist on the tracer */
                ret = event_ust_enable_tracepoint(usess, uchan, event,
-                               filter_expression, filter, exclusion);
+                               filter_expression, filter, exclusion,
+                               internal_event);
                /* We have passed ownership */
                filter_expression = NULL;
                filter = NULL;
                exclusion = NULL;
-               if (ret != LTTNG_OK) {
+               if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
+                       goto already_enabled;
+               } else if (ret != LTTNG_OK) {
                        goto error;
                }
                break;
@@ -1640,7 +1905,7 @@ int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
                if (!agt) {
                        agt = agent_create(domain->type);
                        if (!agt) {
-                               ret = -LTTNG_ERR_NOMEM;
+                               ret = LTTNG_ERR_NOMEM;
                                goto error;
                        }
                        agent_add(agt, usess->agents);
@@ -1650,9 +1915,10 @@ int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
                memset(&uevent, 0, sizeof(uevent));
                uevent.type = LTTNG_EVENT_TRACEPOINT;
                uevent.loglevel_type = LTTNG_EVENT_LOGLEVEL_ALL;
-               default_event_name = event_get_default_agent_ust_name(domain->type);
+               default_event_name = event_get_default_agent_ust_name(
+                               domain->type);
                if (!default_event_name) {
-                       ret = -LTTNG_ERR_FATAL;
+                       ret = LTTNG_ERR_FATAL;
                        goto error;
                }
                strncpy(uevent.name, default_event_name, sizeof(uevent.name));
@@ -1677,46 +1943,61 @@ int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
                        default_chan_name = DEFAULT_PYTHON_CHANNEL_NAME;
                        break;
                default:
-                       /* The switch/case we are in should avoid this else big problem */
+                       /* The switch/case we are in makes this impossible */
                        assert(0);
                }
 
                {
+                       char *filter_expression_copy = NULL;
                        struct lttng_filter_bytecode *filter_copy = NULL;
 
                        if (filter) {
-                               filter_copy = zmalloc(
-                                       sizeof(struct lttng_filter_bytecode)
-                                       + filter->len);
+                               const size_t filter_size = sizeof(
+                                               struct lttng_filter_bytecode)
+                                               + filter->len;
+
+                               filter_copy = zmalloc(filter_size);
                                if (!filter_copy) {
+                                       ret = LTTNG_ERR_NOMEM;
                                        goto error;
                                }
+                               memcpy(filter_copy, filter, filter_size);
 
-                               memcpy(filter_copy, filter,
-                                       sizeof(struct lttng_filter_bytecode)
-                                       + filter->len);
+                               filter_expression_copy =
+                                               strdup(filter_expression);
+                               if (!filter_expression) {
+                                       ret = LTTNG_ERR_NOMEM;
+                               }
+
+                               if (!filter_expression_copy || !filter_copy) {
+                                       free(filter_expression_copy);
+                                       free(filter_copy);
+                                       goto error;
+                               }
                        }
 
-                       ret = cmd_enable_event(session, &tmp_dom,
+                       ret = cmd_enable_event_internal(session, &tmp_dom,
                                        (char *) default_chan_name,
-                                       &uevent, filter_expression, filter_copy,
-                                       NULL, wpipe);
-                       /* We have passed ownership */
-                       filter_expression = NULL;
+                                       &uevent, filter_expression_copy,
+                                       filter_copy, NULL, wpipe);
                }
 
-               if (ret != LTTNG_OK && ret != LTTNG_ERR_UST_EVENT_ENABLED) {
+               if (ret == LTTNG_ERR_UST_EVENT_ENABLED) {
+                       goto already_enabled;
+               } else if (ret != LTTNG_OK) {
                        goto error;
                }
 
                /* The wild card * means that everything should be enabled. */
                if (strncmp(event->name, "*", 1) == 0 && strlen(event->name) == 1) {
-                       ret = event_agent_enable_all(usess, agt, event, filter);
-                       filter = NULL;
+                       ret = event_agent_enable_all(usess, agt, event, filter,
+                                       filter_expression);
                } else {
-                       ret = event_agent_enable(usess, agt, event, filter);
-                       filter = NULL;
+                       ret = event_agent_enable(usess, agt, event, filter,
+                                       filter_expression);
                }
+               filter = NULL;
+               filter_expression = NULL;
                if (ret != LTTNG_OK) {
                        goto error;
                }
@@ -1730,6 +2011,7 @@ int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
 
        ret = LTTNG_OK;
 
+already_enabled:
 error:
        free(filter_expression);
        free(filter);
@@ -1738,10 +2020,43 @@ error:
        return ret;
 }
 
+/*
+ * Command LTTNG_ENABLE_EVENT processed by the client thread.
+ * We own filter, exclusion, and filter_expression.
+ */
+int cmd_enable_event(struct ltt_session *session, struct lttng_domain *domain,
+               char *channel_name, struct lttng_event *event,
+               char *filter_expression,
+               struct lttng_filter_bytecode *filter,
+               struct lttng_event_exclusion *exclusion,
+               int wpipe)
+{
+       return _cmd_enable_event(session, domain, channel_name, event,
+                       filter_expression, filter, exclusion, wpipe, false);
+}
+
+/*
+ * Enable an event which is internal to LTTng. An internal should
+ * never be made visible to clients and are immune to checks such as
+ * reserved names.
+ */
+static int cmd_enable_event_internal(struct ltt_session *session,
+               struct lttng_domain *domain,
+               char *channel_name, struct lttng_event *event,
+               char *filter_expression,
+               struct lttng_filter_bytecode *filter,
+               struct lttng_event_exclusion *exclusion,
+               int wpipe)
+{
+       return _cmd_enable_event(session, domain, channel_name, event,
+                       filter_expression, filter, exclusion, wpipe, true);
+}
+
 /*
  * Command LTTNG_LIST_TRACEPOINTS processed by the client thread.
  */
-ssize_t cmd_list_tracepoints(int domain, struct lttng_event **events)
+ssize_t cmd_list_tracepoints(enum lttng_domain_type domain,
+               struct lttng_event **events)
 {
        int ret;
        ssize_t nb_events = 0;
@@ -1785,7 +2100,7 @@ error:
 /*
  * Command LTTNG_LIST_TRACEPOINT_FIELDS processed by the client thread.
  */
-ssize_t cmd_list_tracepoint_fields(int domain,
+ssize_t cmd_list_tracepoint_fields(enum lttng_domain_type domain,
                struct lttng_event_field **fields)
 {
        int ret;
@@ -1823,7 +2138,7 @@ ssize_t cmd_list_syscalls(struct lttng_event **events)
  * Called with session lock held.
  */
 ssize_t cmd_list_tracker_pids(struct ltt_session *session,
-               int domain, int32_t **pids)
+               enum lttng_domain_type domain, int32_t **pids)
 {
        int ret;
        ssize_t nr_pids = 0;
@@ -1897,9 +2212,7 @@ int cmd_start_trace(struct ltt_session *session)
         * possible to enable channel thus inform the client.
         */
        if (usess && usess->domain_global.channels) {
-               rcu_read_lock();
                nb_chan += lttng_ht_get_count(usess->domain_global.channels);
-               rcu_read_unlock();
        }
        if (ksession) {
                nb_chan += ksession->channel_count;
@@ -2181,7 +2494,7 @@ int cmd_create_session_snapshot(char *name, struct lttng_uri *uris,
         * Create session in no output mode with URIs set to NULL. The uris we've
         * received are for a default snapshot output if one.
         */
-       ret = cmd_create_session_uri(name, NULL, 0, creds, -1);
+       ret = cmd_create_session_uri(name, NULL, 0, creds, 0);
        if (ret != LTTNG_OK) {
                goto error;
        }
@@ -2282,7 +2595,8 @@ int cmd_destroy_session(struct ltt_session *session, int wpipe)
 /*
  * Command LTTNG_CALIBRATE processed by the client thread.
  */
-int cmd_calibrate(int domain, struct lttng_calibrate *calibrate)
+int cmd_calibrate(enum lttng_domain_type domain,
+               struct lttng_calibrate *calibrate)
 {
        int ret;
 
@@ -2339,8 +2653,9 @@ error:
 /*
  * Command LTTNG_REGISTER_CONSUMER processed by the client thread.
  */
-int cmd_register_consumer(struct ltt_session *session, int domain,
-               const char *sock_path, struct consumer_data *cdata)
+int cmd_register_consumer(struct ltt_session *session,
+               enum lttng_domain_type domain, const char *sock_path,
+               struct consumer_data *cdata)
 {
        int ret, sock;
        struct consumer_socket *socket = NULL;
@@ -2456,6 +2771,10 @@ ssize_t cmd_list_domains(struct ltt_session *session,
 
        if (session->kernel_session != NULL) {
                (*domains)[index].type = LTTNG_DOMAIN_KERNEL;
+
+               /* Kernel session buffer type is always GLOBAL */
+               (*domains)[index].buf_type = LTTNG_BUFFER_GLOBAL;
+
                index++;
        }
 
@@ -2487,8 +2806,8 @@ error:
 /*
  * Command LTTNG_LIST_CHANNELS processed by the client thread.
  */
-ssize_t cmd_list_channels(int domain, struct ltt_session *session,
-               struct lttng_channel **channels)
+ssize_t cmd_list_channels(enum lttng_domain_type domain,
+               struct ltt_session *session, struct lttng_channel **channels)
 {
        int ret;
        ssize_t nb_chan = 0;
@@ -2541,8 +2860,9 @@ error:
 /*
  * Command LTTNG_LIST_EVENTS processed by the client thread.
  */
-ssize_t cmd_list_events(int domain, struct ltt_session *session,
-               char *channel_name, struct lttng_event **events)
+ssize_t cmd_list_events(enum lttng_domain_type domain,
+               struct ltt_session *session, char *channel_name,
+               struct lttng_event **events, size_t *total_size)
 {
        int ret = 0;
        ssize_t nb_event = 0;
@@ -2551,14 +2871,16 @@ ssize_t cmd_list_events(int domain, struct ltt_session *session,
        case LTTNG_DOMAIN_KERNEL:
                if (session->kernel_session != NULL) {
                        nb_event = list_lttng_kernel_events(channel_name,
-                                       session->kernel_session, events);
+                                       session->kernel_session, events,
+                                       total_size);
                }
                break;
        case LTTNG_DOMAIN_UST:
        {
                if (session->ust_session != NULL) {
                        nb_event = list_lttng_ust_global_events(channel_name,
-                                       &session->ust_session->domain_global, events);
+                                       &session->ust_session->domain_global, events,
+                                       total_size);
                }
                break;
        }
@@ -2572,7 +2894,12 @@ ssize_t cmd_list_events(int domain, struct ltt_session *session,
                        rcu_read_lock();
                        cds_lfht_for_each_entry(session->ust_session->agents->ht,
                                        &iter.iter, agt, node.node) {
-                               nb_event = list_lttng_agent_events(agt, events);
+                               if (agt->domain == domain) {
+                                       nb_event = list_lttng_agent_events(
+                                                       agt, events,
+                                                       total_size);
+                                       break;
+                               }
                        }
                        rcu_read_unlock();
                }
This page took 0.038504 seconds and 4 git commands to generate.