lttng-ctl: manage memory automatically in kernel tracer status check

Use a unique_ptr to manage the dynamically allocated payload returned by
lttng_ctl_ask_sessiond.

Signed-off-by: Jérémie Galarneau <jeremie.galarneau@efficios.com>
Change-Id: I685fc03c1da7ff7903503ed82636d27f98f9895e

diff --git a/src/lib/lttng-ctl/lttng-ctl.cpp b/src/lib/lttng-ctl/lttng-ctl.cpp
index 22823d344bd1d556a3248ab63c0f093cd7cd7ac7..96ed7b41b8abc5f5afc60a6b20de84950c1445ca 100644 (file)
--- a/src/lib/lttng-ctl/lttng-ctl.cpp
+++ b/src/lib/lttng-ctl/lttng-ctl.cpp
@@ -24,6 +24,7 @@
 #include <common/filter/filter-ast.hpp>
 #include <common/filter/filter-parser.hpp>
 #include <common/filter/memstream.hpp>
+#include <common/make-unique-wrapper.hpp>
 #include <common/payload-view.hpp>
 #include <common/payload.hpp>
 #include <common/sessiond-comm/sessiond-comm.hpp>
@@ -2882,28 +2883,27 @@ end:
  *
  * Sets the value of the argument
  */
-enum lttng_error_code lttng_get_kernel_tracer_status(enum lttng_kernel_tracer_status *status)
+enum lttng_error_code lttng_get_kernel_tracer_status(enum lttng_kernel_tracer_status *out_status)
 {
-       enum lttng_error_code ret = LTTNG_ERR_INVALID;
-
-       if (status == nullptr) {
+       if (out_status == nullptr) {
                return LTTNG_ERR_INVALID;
        }
 
        struct lttcomm_session_msg lsm = {};
        lsm.cmd_type = LTTCOMM_SESSIOND_COMMAND_KERNEL_TRACER_STATUS;
 
-       uint32_t *u_status = nullptr;
-       const auto ask_ret = lttng_ctl_ask_sessiond(&lsm, (void **) &u_status);
+       uint32_t *raw_tracer_status = nullptr;
+       const auto ask_ret = lttng_ctl_ask_sessiond(&lsm, (void **) &raw_tracer_status);
+
+       const auto tracer_status =
+               lttng::make_unique_wrapper<uint32_t, lttng::free>(raw_tracer_status);
+
        if (ask_ret != 4) {
-               goto end;
+               return LTTNG_ERR_INVALID;
        }
 
-       *status = (enum lttng_kernel_tracer_status) * u_status;
-       ret = LTTNG_OK;
-end:
-       free(u_status);
-       return ret;
+       *out_status = (enum lttng_kernel_tracer_status) * tracer_status;
+       return LTTNG_OK;
 }
 
 /*