clock override: introduce getter API for lttng tools

[lttng-ust.git] / include / lttng / ust-clock.h

diff --git a/include/lttng/ust-clock.h b/include/lttng/ust-clock.h
index 44b249b0651010553a97175453eb915ca26b6361..d608a933b8b26158351f7fb427903a4f324c9104 100644 (file)
--- a/include/lttng/ust-clock.h
+++ b/include/lttng/ust-clock.h
@@ -16,36 +16,47 @@
  * success.
  */
 
+typedef uint64_t (*lttng_ust_clock_read64_function)(void);
+typedef uint64_t (*lttng_ust_clock_freq_function)(void);
+typedef int (*lttng_ust_clock_uuid_function)(char *uuid);
+typedef const char *(*lttng_ust_clock_name_function)(void);
+typedef const char *(*lttng_ust_clock_description_function)(void);
+
 /*
- * Set clock override read callback. This callback should return the
+ * Set/Get clock override read callback. This callback should return the
  * current clock time (a 64-bit monotonic counter).
  */
-int lttng_ust_trace_clock_set_read64_cb(uint64_t (*read64)(void));
+int lttng_ust_trace_clock_set_read64_cb(lttng_ust_clock_read64_function read64_cb);
+int lttng_ust_trace_clock_get_read64_cb(lttng_ust_clock_read64_function *read64_cb);
 
 /*
- * Set clock override frequency callback. This callback should return
+ * Set/Get clock override frequency callback. This callback should return
  * the frequency of the clock in cycles per second.
  */
-int lttng_ust_trace_clock_set_freq_cb(uint64_t (*freq)(void));
+int lttng_ust_trace_clock_set_freq_cb(lttng_ust_clock_freq_function freq_cb);
+int lttng_ust_trace_clock_get_freq_cb(lttng_ust_clock_freq_function *freq_cb);
 
 /*
- * Set clock override unique identifier.
+ * Set/Get clock override unique identifier.
  * LTTNG_UST_UUID_STR_LEN is the maximum length of uuid string. Includes
  * final \0.
  */
 #define LTTNG_UST_UUID_STR_LEN         37
 
-int lttng_ust_trace_clock_set_uuid_cb(int (*uuid)(char *uuid));
+int lttng_ust_trace_clock_set_uuid_cb(lttng_ust_clock_uuid_function uuid_cb);
+int lttng_ust_trace_clock_get_uuid_cb(lttng_ust_clock_uuid_function *uuid_cb);
 
 /*
- * Set clock override name.
+ * Set/Get clock override name.
  */
-int lttng_ust_trace_clock_set_name_cb(const char *(*name)(void));
+int lttng_ust_trace_clock_set_name_cb(lttng_ust_clock_name_function name_cb);
+int lttng_ust_trace_clock_get_name_cb(lttng_ust_clock_name_function *name_cb);
 
 /*
- * Set clock override description.
+ * Set/Get clock override description.
  */
-int lttng_ust_trace_clock_set_description_cb(const char *(*description)(void));
+int lttng_ust_trace_clock_set_description_cb(lttng_ust_clock_description_function description_cb);
+int lttng_ust_trace_clock_get_description_cb(lttng_ust_clock_description_function *description_cb);
 
 /*
  * Use the clock override rather than the default clock.