add logutils fn for finding job runtime

method for calculating this depends on log format version,
so a helper routine seems useful for utilities

Author: Shane Snyder

darshan-util/darshan-analyzer.c

@@ -97,8 +97,7 @@ int process_log(const char *fname, double *io_ratio, int *used_mpio, int *used_p
     if (file->mod_map[DARSHAN_PNETCDF_MOD].len > 0)
         *used_pnet += 1;
 
-    total_job_time = job.end_time_sec + (job.end_time_nsec / 1e9);
-    total_job_time -= job.start_time_sec + (job.start_time_nsec / 1e9);
+    darshan_log_get_job_runtime(file, job, &total_job_time);
 
     if (f_count > 0)
     {

darshan-util/darshan-dxt-parser.c

@@ -115,8 +115,7 @@ int main(int argc, char **argv)
     tmp_time += job.end_time_sec;
     printf("# end_time_asci: %s", ctime(&tmp_time));
     printf("# nprocs: %" PRId64 "\n", job.nprocs);
-    run_time = job.end_time_sec + (job.end_time_nsec / 1e9);
-    run_time -= job.start_time_sec + (job.start_time_nsec / 1e9);
+    darshan_log_get_job_runtime(fd, job, &run_time);
     printf("# run time: %.4lf\n", run_time);
     for (token = strtok_r(job.metadata, "\n", &save);
         token != NULL;

darshan-util/darshan-logutils.c

@@ -934,6 +934,29 @@ char *darshan_log_get_lib_version(void)
     return darshan_util_lib_ver;
 }
 
+int darshan_log_get_job_runtime(darshan_fd fd, struct darshan_job job, double *runtime)
+{
+    int log_ver_maj, log_ver_min;
+    int ret;
+    *runtime = 0;
+
+    /* get major/minor version numbers */
+    ret = darshan_log_get_format_version(fd->version, &log_ver_maj, &log_ver_min);
+    if(ret < 0)
+    {
+        fprintf(stderr, "Error: unable to parse log file format version.\n");
+        return(-1);
+    }
+
+    if(((log_ver_maj == 3) && (log_ver_min >= 41)) || (log_ver_maj > 3))
+        *runtime = (double)((job.end_time_sec + (job.end_time_nsec / 1e9)) -
+                    (job.start_time_sec + (job.start_time_nsec / 1e9)));
+    else
+        *runtime = (double)(job.end_time_sec - job.start_time_sec + 1);
+
+    return(0);
+}
+
 /********************************************************
  *             internal helper functions                *
  ********************************************************/

darshan-util/darshan-logutils.h

@@ -211,6 +211,7 @@ int darshan_log_put_mod(darshan_fd fd, darshan_module_id mod_id,
 void darshan_log_close(darshan_fd file);
 void darshan_log_print_version_warnings(const char *version_string);
 char *darshan_log_get_lib_version(void);
+int darshan_log_get_job_runtime(darshan_fd fd, struct darshan_job job, double *runtime);
 void darshan_log_get_modules(darshan_fd fd, struct darshan_mod_info **mods,
     int* count);
 void darshan_log_get_name_records(darshan_fd fd,

darshan-util/darshan-parser.c

@@ -214,8 +214,7 @@ int main(int argc, char **argv)
     tmp_time += job.end_time_sec;
     printf("# end_time_asci: %s", ctime(&tmp_time));
     printf("# nprocs: %" PRId64 "\n", job.nprocs);
-    run_time = job.end_time_sec + (job.end_time_nsec / 1e9);
-    run_time -= job.start_time_sec + (job.start_time_nsec / 1e9);
+    darshan_log_get_job_runtime(fd, job, &run_time);
     printf("# run time: %.4lf\n", run_time);
     for(token=strtok_r(job.metadata, "\n", &save);
         token != NULL;