fix pydarshan defs for darshan-util accumulators

Author: Shane Snyder

darshan-util/pydarshan/darshan/backend/api_def_c.py

@@ -21,21 +21,6 @@
     struct darshan_file_category_counters;
 };
 
-
-
-struct darshan_accumulator {
-    int64_t module_id;
-    int64_t job_nprocs;
-    void* agg_record;
-    int num_records;
-    void *file_hash_table;
-    double shared_io_total_time_by_slowest;
-    int64_t total_bytes;
-    double *rank_cumul_io_total_time;
-    double *rank_cumul_rw_only_time;
-    double *rank_cumul_md_only_time;
-};
-
 struct darshan_mnt_info
 {
     char mnt_type[3031];
@@ -51,10 +36,14 @@
     int partial_flag;
 };
 
-int darshan_accumulator_emit(struct darshan_accumulator, struct darshan_derived_metrics*, void* aggregation_record);
-int darshan_accumulator_destroy(struct darshan_accumulator);
-int darshan_accumulator_create(enum darshan_module_id, int64_t, struct darshan_accumulator*);
-int darshan_accumulator_inject(struct darshan_accumulator, void*, int);
+/* opaque accumulator reference */
+struct darshan_accumulator_st;
+typedef struct darshan_accumulator_st* darshan_accumulator;
+
+int darshan_accumulator_create(enum darshan_module_id, int64_t, darshan_accumulator*);
+int darshan_accumulator_inject(darshan_accumulator, void*, int);
+int darshan_accumulator_emit(darshan_accumulator, struct darshan_derived_metrics*, void* aggregation_record);
+int darshan_accumulator_destroy(darshan_accumulator);
 
 /* from darshan-log-format.h */
 typedef uint64_t darshan_record_id;

darshan-util/pydarshan/darshan/backend/cffi_backend.py

@@ -662,14 +662,14 @@ def log_get_accumulator(log, mod_name: str):
         return None
     mod_type = _structdefs[mod_name]
 
-    darshan_accumulator = ffi.new("struct darshan_accumulator *")
     buf = ffi.new("void **")
     r = libdutil.darshan_log_get_record(log['handle'], modules[mod_name]['idx'], buf)
     rbuf = ffi.cast(mod_type, buf)
 
-    libdutil.darshan_accumulator_create(modules[mod_name]['idx'],
-                                        jobrec[0].nprocs,
-                                        darshan_accumulator)
+    darshan_accumulator = ffi.new("darshan_accumulator *")
+    r = libdutil.darshan_accumulator_create(modules[mod_name]['idx'],
+                                            jobrec[0].nprocs,
+                                            darshan_accumulator)
 
     # TODO: fix the segfault on the inject call below
     r = libdutil.darshan_accumulator_inject(darshan_accumulator[0], rbuf[0], 1)