Add the filter expression to the enable_event agent protocol message

[lttng-tools.git] / src / bin / lttng-sessiond / agent.c

diff --git a/src/bin/lttng-sessiond/agent.c b/src/bin/lttng-sessiond/agent.c
index 35f0e578a0da725863f1b07be9d385a577371ea2..def13707bdf52fd40149dc0d9705393b4652b618 100644 (file)
--- a/src/bin/lttng-sessiond/agent.c
+++ b/src/bin/lttng-sessiond/agent.c
@@ -360,7 +360,9 @@ error:
 static int enable_event(struct agent_app *app, struct agent_event *event)
 {
        int ret;
+       char *bytes_to_send;
        uint64_t data_size;
+       size_t filter_expression_length;
        uint32_t reply_ret_code;
        struct lttcomm_agent_enable msg;
        struct lttcomm_agent_generic_reply reply;
@@ -372,7 +374,16 @@ static int enable_event(struct agent_app *app, struct agent_event *event)
        DBG2("Agent enabling event %s for app pid: %d and socket %d", event->name,
                        app->pid, app->sock->fd);
 
-       data_size = sizeof(msg);
+       /*
+        * Calculate the payload's size, which is the fixed-size struct followed
+        * by the variable-length filter expression (+1 for the ending \0).
+        */
+       if (!event->filter_expression) {
+               filter_expression_length = 0;
+       } else {
+               filter_expression_length = strlen(event->filter_expression) + 1;
+       }
+       data_size = sizeof(msg) + filter_expression_length;
 
        ret = send_header(app->sock, data_size, AGENT_CMD_ENABLE, 0);
        if (ret < 0) {
@@ -383,7 +394,22 @@ static int enable_event(struct agent_app *app, struct agent_event *event)
        msg.loglevel_value = event->loglevel_value;
        msg.loglevel_type = event->loglevel_type;
        strncpy(msg.name, event->name, sizeof(msg.name));
-       ret = send_payload(app->sock, &msg, sizeof(msg));
+       msg.filter_expression_length = filter_expression_length;
+
+       bytes_to_send = zmalloc(data_size);
+       if (!bytes_to_send) {
+               ret = LTTNG_ERR_NOMEM;
+               goto error;
+       }
+
+       memcpy(bytes_to_send, &msg, sizeof(msg));
+       if (filter_expression_length > 0) {
+               memcpy(bytes_to_send + sizeof(msg), event->filter_expression,
+                               filter_expression_length);
+       }
+
+       ret = send_payload(app->sock, bytes_to_send, data_size);
+       free(bytes_to_send);
        if (ret < 0) {
                goto error_io;
        }