Send data pending status as part of payload instead of an invalid error

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

diff --git a/src/bin/lttng-sessiond/main.c b/src/bin/lttng-sessiond/main.c
index 91dd047e763d76968044cc5e038f93215d539a7f..792f519abbddb3cae7c2a1714a42ed96fff16361 100644 (file)
--- a/src/bin/lttng-sessiond/main.c
+++ b/src/bin/lttng-sessiond/main.c
@@ -73,6 +73,7 @@
 #include "save.h"
 #include "load-session-thread.h"
 #include "syscall.h"
+#include "agent.h"
 
 #define CONSUMERD_FILE "lttng-consumerd"
 
@@ -305,6 +306,9 @@ const char * const config_section_name = "sessiond";
 /* Load session thread information to operate. */
 struct load_session_thread_data *load_info;
 
+/* Global hash tables */
+struct lttng_ht *agent_apps_ht_by_sock = NULL;
+
 /*
  * Whether sessiond is ready for commands/health check requests.
  * NR_LTTNG_SESSIOND_READY must match the number of calls to
@@ -3762,7 +3766,35 @@ skip_domain:
        }
        case LTTNG_DATA_PENDING:
        {
-               ret = cmd_data_pending(cmd_ctx->session);
+               int pending_ret;
+
+               /* 1 byte to return whether or not data is pending */
+               ret = setup_lttng_msg(cmd_ctx, 1);
+               if (ret < 0) {
+                       goto setup_error;
+               }
+
+               pending_ret = cmd_data_pending(cmd_ctx->session);
+               /*
+                * FIXME
+                *
+                * This function may returns 0 or 1 to indicate whether or not
+                * there is data pending. In case of error, it should return an
+                * LTTNG_ERR code. However, some code paths may still return
+                * a nondescript error code, which we handle by returning an
+                * "unknown" error.
+                */
+               if (pending_ret == 0 || pending_ret == 1) {
+                       ret = LTTNG_OK;
+               } else if (pending_ret < 0) {
+                       ret = LTTNG_ERR_UNK;
+                       goto setup_error;
+               } else {
+                       ret = pending_ret;
+                       goto setup_error;
+               }
+
+               *cmd_ctx->llm->payload = (uint8_t) pending_ret;
                break;
        }
        case LTTNG_SNAPSHOT_ADD_OUTPUT:
@@ -4329,9 +4361,10 @@ static void *thread_manage_clients(void *data)
 
                health_code_update();
 
-               DBG("Sending response (size: %d, retcode: %s)",
+               DBG("Sending response (size: %d, retcode: %s (%d))",
                                cmd_ctx->lttng_msg_size,
-                               lttng_strerror(-cmd_ctx->llm->ret_code));
+                               lttng_strerror(-cmd_ctx->llm->ret_code),
+                               cmd_ctx->llm->ret_code);
                ret = send_unix_sock(sock, cmd_ctx->llm, cmd_ctx->lttng_msg_size);
                if (ret < 0) {
                        ERR("Failed to send data back to client");