Clean up some compiler warnings

`gcc-13 -Wall ...` found a few places we were possibly overrunning
arrays

Author: roblatham00

darshan-runtime/lib/darshan-core.c

@@ -1120,7 +1120,7 @@ static void darshan_get_exe_and_mounts(struct darshan_core_runtime *core,
 static int darshan_should_instrument_app(struct darshan_core_runtime *core)
 {
     char *tmp_str;
-    char *app_name;
+    char *app_name=NULL;
     struct darshan_core_regex *app_regex;
     int app_excluded = 0, app_included = 0;
 
@@ -2064,7 +2064,8 @@ void darshan_log_finalize(char *logfile_name, double start_log_time)
         if(new_logfile_name)
         {
             /* copy partial log file name over to new string */
-            strncpy(new_logfile_name, logfile_name, __DARSHAN_PATH_MAX);
+            strncpy(new_logfile_name, logfile_name, __DARSHAN_PATH_MAX-1);
+            new_logfile_name[__DARSHAN_PATH_MAX-1] = '\0';
             /* retrieve current time stamp */
             end_log_time = darshan_core_wtime_absolute();
             /* find location of .darshan_partial extension */

darshan-util/darshan-diff.c

@@ -61,7 +61,7 @@ int main(int argc, char *argv[])
     struct darshan_mod_record_ref *mod_rec1, *mod_rec2;
     void *mod_buf1, *mod_buf2;
     struct darshan_base_record *base_rec1, *base_rec2;
-    char *file_name1, *file_name2;
+    char *file_name1=NULL, *file_name2=NULL;
     int i;
     int ret;
 

darshan-util/darshan-hdf5-logutils.c

@@ -653,7 +653,7 @@ static void darshan_log_agg_hdf5_files(void *rec, void *agg_rec, int init_flag)
                 break;
             case H5F_F_META_TIME:
                 /* sum */
-                agg_hdf5_rec->counters[i] += hdf5_rec->counters[i];
+                agg_hdf5_rec->fcounters[i] += hdf5_rec->fcounters[i];
                 break;
             default:
                 agg_hdf5_rec->fcounters[i] = -1;

darshan-util/darshan-logutils.c

@@ -163,7 +163,8 @@ darshan_fd darshan_log_open(const char *name)
         free(tmp_fd);
         return(NULL);
     }
-    strncpy(tmp_fd->state->logfile_path, name, __DARSHAN_PATH_MAX);
+    strncpy(tmp_fd->state->logfile_path, name, __DARSHAN_PATH_MAX-1);
+    tmp_fd->state->logfile_path[__DARSHAN_PATH_MAX-1] = '\0';
 
     /* read the header from the log file to init fd data structures */
     ret = darshan_log_get_header(tmp_fd);
@@ -229,7 +230,8 @@ darshan_fd darshan_log_create(const char *name, enum darshan_comp_type comp_type
     }
     tmp_fd->state->creat_flag = 1;
     tmp_fd->partial_flag = partial_flag;
-    strncpy(tmp_fd->state->logfile_path, name, __DARSHAN_PATH_MAX);
+    strncpy(tmp_fd->state->logfile_path, name, __DARSHAN_PATH_MAX-1);
+    tmp_fd->state->logfile_path[__DARSHAN_PATH_MAX-1] = '\0';
 
     /* position file pointer to prealloc space for the log file header
      * NOTE: the header is written at close time, after all internal data