1. Close the log file when the file closing flag is true in H5F_vfd_swmr_close_or_flush().

2. Move the log test to the group performance test code with an option.
3. Use constant variables for log message lengths.
4. Misc. clean-up.

8 files changed, 77 insertions, 2975 deletions

diff --git a/MANIFEST b/MANIFEST
index 208bfc3..75a7aca 100644
--- a/MANIFEST
+++ b/MANIFEST
@@ -1444,7 +1444,6 @@
 ./test/vfd_swmr_vlstr_writer.c
 ./test/vfd_swmr_writer.c
 ./test/vfd_swmr_zoo_writer.c
-./test/vfd_swmr_log_writer.c
 ./test/vfd.c
 ./test/vol.c
 ./test/vol_plugin.c
diff --git a/src/H5FDvfd_swmr_private.h b/src/H5FDvfd_swmr_private.h
index 02e1c44..985bd70 100644
--- a/src/H5FDvfd_swmr_private.h
+++ b/src/H5FDvfd_swmr_private.h
@@ -84,8 +84,5 @@ H5_DLL herr_t H5F_vfd_swmr_insert_entry_eot(struct H5F_t *f);
 H5_DLL void   H5F_vfd_swmr_update_entry_eot(eot_queue_entry_t *);
 H5_DLL herr_t H5F_dump_eot_queue(void);
 
-/***************************************/
-/* Log Macros and Functions            */
-/***************************************/
 
 #endif /* H5FDvfd_swmr_private_H */
diff --git a/src/H5Fint.c b/src/H5Fint.c
index 1adc7d5..c0579bd 100644
--- a/src/H5Fint.c
+++ b/src/H5Fint.c
@@ -2014,23 +2014,6 @@ H5F_open(const char *name, unsigned flags, hid_t fcpl_id, hid_t fapl_id)
     /* Short cuts */
     shared = file->shared;
 
-    /* Set up the VFD SWMR LOG file */
-    /* Kent*/
-    if (vfd_swmr_config_ptr->version) {
-        if (HDstrlen(vfd_swmr_config_ptr->log_file_path) > 0)
-            shared->vfd_swmr_log_on = TRUE;
-        if (TRUE == shared->vfd_swmr_log_on) {
-            /* Create the log file */
-            if ((shared->vfd_swmr_log_file_ptr = HDfopen(vfd_swmr_config_ptr->log_file_path, "w")) == NULL)
-                HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to create the log file")
-            if (H5_timer_init(&(shared->vfd_swmr_log_start_time)) < 0)
-                HGOTO_ERROR(H5E_FILE, H5E_CANTGET, NULL, "can't initialize HDF5 timer.")
-            if (H5_timer_start(&(shared->vfd_swmr_log_start_time)) < 0)
-                HGOTO_ERROR(H5E_FILE, H5E_CANTGET, NULL, "can't obtain the time from the HDF5 timer.")
-        }
-    }
-    /* End of Kent */
-
     lf = shared->lf;
 
     /* Set the file locking flag. If the file is already open, the file
@@ -2110,6 +2093,22 @@ H5F_open(const char *name, unsigned flags, hid_t fcpl_id, hid_t fapl_id)
 
     /* Checked if configured for VFD SWMR */
     if (H5F_VFD_SWMR_CONFIG(file)) {
+
+        /* Set up the VFD SWMR LOG file */
+        /* Kent*/
+        if (HDstrlen(vfd_swmr_config_ptr->log_file_path) > 0)
+            shared->vfd_swmr_log_on = TRUE;
+        if (TRUE == shared->vfd_swmr_log_on) {
+            /* Create the log file */
+            if ((shared->vfd_swmr_log_file_ptr = HDfopen(vfd_swmr_config_ptr->log_file_path, "w")) == NULL)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTOPENFILE, NULL, "unable to create the log file")
+            if (H5_timer_init(&(shared->vfd_swmr_log_start_time)) < 0)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTGET, NULL, "can't initialize HDF5 timer.")
+            if (H5_timer_start(&(shared->vfd_swmr_log_start_time)) < 0)
+                HGOTO_ERROR(H5E_FILE, H5E_CANTGET, NULL, "can't obtain the time from the HDF5 timer.")
+        }
+        /* End of Kent */
+
         /* Initialization for VFD SWMR writer and reader */
         if (1 == shared->nrefs) {
             if (H5F_vfd_swmr_init(file, file_create) < 0)
diff --git a/src/H5Fpkg.h b/src/H5Fpkg.h
index 3de5a84..3bece42 100644
--- a/src/H5Fpkg.h
+++ b/src/H5Fpkg.h
@@ -625,7 +625,7 @@ H5_DLL herr_t H5F__reparse_file_lock_variable_test(void);
  * a log entry_type_code,  which generates a log tag,  and the message log_info, which
  * the developers want to save into a log file.
  *
- * The macro H5F_POST_VFD_SWMR_LOG_ENTRY_RELEASE(f, c, number_entry_production, m) is
+ * The macro H5F_POST_VFD_SWMR_LOG_ENTRY_PRODUCTION(f, c, number_entry_production, m) is
  * called by H5F_POST_VFD_SWMR_LOG_ENTRY when the HDF5 library is built with the
  * production mode. Number_entry_production will control the number of entry tags that
  * applications can receive. Currently this number is set to 1 and is subject to change
@@ -649,21 +649,21 @@ H5_DLL void H5F_post_vfd_swmr_log_entry(H5F_t *f, int entry_type_code, char *log
         }                                                                                                    \
     } while (0)
 
-#define H5F_POST_VFD_SWMR_LOG_ENTRY_RELEASE(fp, entry_type_code, max_code, log_info)                         \
+#define H5F_POST_VFD_SWMR_LOG_ENTRY_PRODUCTION(fp, entry_type_code, max_code, log_info)                         \
     do {                                                                                                     \
         if (entry_type_code < max_code) {                                                                    \
             H5F_POST_VFD_SWMR_LOG_ENTRY_INTERNAL(fp, entry_type_code, log_info);                             \
         }                                                                                                    \
     } while (0)
 
-/* Note: change H5F_POST_VFD_SWMR_LOG_ENTRY_RELEASE(f, c, 1, m) on the following lines to
- *       H5F_POST_VFD_SWMR_LOG_ENTRY_RELEASE(f, c, your_number_entry_production, m)
+/* Note: change H5F_POST_VFD_SWMR_LOG_ENTRY_PRODUCTION(f, c, 1, m) on the following lines to
+ *       H5F_POST_VFD_SWMR_LOG_ENTRY_PRODUCTION(f, c, your_number_entry_production, m)
  *       as necessary.
  */
 #ifndef NDEBUG
 #define H5F_POST_VFD_SWMR_LOG_ENTRY(f, c, m) H5F_POST_VFD_SWMR_LOG_ENTRY_INTERNAL(f, c, m)
 #else
-#define H5F_POST_VFD_SWMR_LOG_ENTRY(f, c, m) H5F_POST_VFD_SWMR_LOG_ENTRY_RELEASE(f, c, 1, m)
+#define H5F_POST_VFD_SWMR_LOG_ENTRY(f, c, m) H5F_POST_VFD_SWMR_LOG_ENTRY_PRODUCTION(f, c, 1, m)
 #endif
 
 #endif /* H5Fpkg_H */
diff --git a/src/H5Fvfd_swmr.c b/src/H5Fvfd_swmr.c
index 476af3e..9404cf4 100644
--- a/src/H5Fvfd_swmr.c
+++ b/src/H5Fvfd_swmr.c
@@ -54,6 +54,7 @@
 #define nanosecs_per_second    1000000000 /* nanoseconds per second */
 #define nanosecs_per_tenth_sec 100000000  /* nanoseconds per 0.1 second */
 
+
 /* Declare an array of string to identify the VFD SMWR Log tags.
  * Note this array is used to generate the entry tag by the log reporting macro
  * H5F_POST_VFD_SWMR_LOG_ENTRY.
@@ -86,6 +87,12 @@ static const char *H5Fvfd_swmr_log_tags[] = {
  */
 const char *log_fmt_str = "%-26s: %.3lf s: %s\n";
 
+/* The length of the EOT processing time log message, subject to change */ 
+const unsigned int eot_pt_log_mesg_length = 48; 
+
+/* The length of error message in the log */
+const unsigned int log_err_mesg_length = 14;
+
 /********************/
 /* Local Prototypes */
 /********************/
@@ -350,8 +357,9 @@ H5F_vfd_swmr_close_or_flush(H5F_t *f, hbool_t closing)
         if (H5F__vfd_swmr_update_end_of_tick_and_tick_num(shared, TRUE) < 0)
             HDONE_ERROR(H5E_FILE, H5E_CANTSET, FAIL, "unable to update end of tick");
     }
-#if 1 /*Kent  Save the end of close or flush info. to the log file, subject to comment out. */
-    H5F_POST_VFD_SWMR_LOG_ENTRY(f, 2, "VFD SWMR File close or flush ends");
+#if 1 /*Kent  Save the end of close info. to the log file, subject to comment out. */
+    if(closing) 
+        H5F_POST_VFD_SWMR_LOG_ENTRY(f, 2, "VFD SWMR File close ends");
 #endif
 done:
 
@@ -359,7 +367,7 @@ done:
      * Please REVIEW to ensure this is the right place to
      * close the log file.
      */
-    if (shared->vfd_swmr_log_on) {
+    if (shared->vfd_swmr_log_on && closing) {
         H5_timer_stop(&(shared->vfd_swmr_log_start_time));
         HDfclose(shared->vfd_swmr_log_file_ptr);
     }
@@ -948,11 +956,12 @@ done:
         if (H5_timer_get_times(shared->vfd_swmr_log_start_time, &current_time) < 0)
             HGOTO_ERROR(H5E_FILE, H5E_CANTGET, FAIL, "can't get time from H5_timer_get_times")
         end_elapsed_time = current_time.elapsed;
-        log_msg          = HDmalloc(48);
-        temp_time        = (unsigned int)((end_elapsed_time - start_elapsed_time) * 1000);
-        HDsprintf(log_msg, "Writer time is %u milliseconds", temp_time);
-        H5F_POST_VFD_SWMR_LOG_ENTRY(f, 0, log_msg);
-        HDfree(log_msg);
+        if(NULL != (log_msg = HDmalloc(eot_pt_log_mesg_length*sizeof(char)))) {
+            temp_time        = (unsigned int)((end_elapsed_time - start_elapsed_time) * 1000);
+            HDsprintf(log_msg, "Writer time is %u milliseconds", temp_time);
+            H5F_POST_VFD_SWMR_LOG_ENTRY(f, 0, log_msg);
+            HDfree(log_msg);
+        }
     }
     /* Kent */
     FUNC_LEAVE_NOAPI(ret_value)
@@ -1988,11 +1997,12 @@ H5F_post_vfd_swmr_log_entry(H5F_t *f, int entry_type_code, char *log_info)
        else obtain the elapsed time in seconds since the log file
             was created and write the time to the log file. */
     if (H5_timer_get_times(f->shared->vfd_swmr_log_start_time, &current_time) < 0) {
-        gettime_error = HDmalloc(14);
-        HDsprintf(gettime_error, "gettime_error");
-        HDfprintf(f->shared->vfd_swmr_log_file_ptr, "%-26s:  %s\n", H5Fvfd_swmr_log_tags[entry_type_code],
-                  gettime_error);
-        HDfree(gettime_error);
+        if(NULL != (gettime_error = HDmalloc(log_err_mesg_length*sizeof(char)))) {
+            HDsprintf(gettime_error, "gettime_error");
+            HDfprintf(f->shared->vfd_swmr_log_file_ptr, "%-26s:  %s\n", H5Fvfd_swmr_log_tags[entry_type_code],
+                      gettime_error);
+            HDfree(gettime_error);
+        }
     }
     else {
         temp_time = current_time.elapsed;
diff --git a/test/Makefile.am b/test/Makefile.am
index a97e968..87b2925 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -56,7 +56,6 @@ SCRIPT_DEPEND = error_test$(EXEEXT) err_compat$(EXEEXT) links_env$(EXEEXT) \
     vfd_swmr_zoo_reader$(EXEEXT) vfd_swmr_zoo_writer$(EXEEXT) \
     vfd_swmr_gperf_reader$(EXEEXT) vfd_swmr_gperf_writer$(EXEEXT) \
     vfd_swmr_gfail_reader$(EXEEXT) vfd_swmr_gfail_writer$(EXEEXT) \
-    vfd_swmr_log_reader$(EXEEXT) vfd_swmr_log_writer$(EXEEXT) \
     vds_env$(EXEEXT) \
     vds_swmr_gen$(EXEEXT) vds_swmr_reader$(EXEEXT) vds_swmr_writer$(EXEEXT)
 if HAVE_SHARED_CONDITIONAL
@@ -116,7 +115,6 @@ check_PROGRAMS=$(TEST_PROG) error_test err_compat tcheck_version \
     vfd_swmr_attrdset_reader vfd_swmr_attrdset_writer \
     vfd_swmr_gperf_reader vfd_swmr_gperf_writer \
     vfd_swmr_gfail_reader vfd_swmr_gfail_writer \
-    vfd_swmr_log_reader vfd_swmr_log_writer \
 	vfd_swmr_check_compat \
     vfd_swmr_dsetchks_reader vfd_swmr_dsetchks_writer \
     swmr_check_compat_vfd vds_env vds_swmr_gen vds_swmr_reader vds_swmr_writer \
@@ -186,7 +184,6 @@ vfd_swmr_bigset_reader_SOURCES=vfd_swmr_bigset_writer.c
 vfd_swmr_group_reader_SOURCES=vfd_swmr_group_writer.c
 vfd_swmr_gperf_reader_SOURCES=vfd_swmr_gperf_writer.c
 vfd_swmr_gfail_reader_SOURCES=vfd_swmr_gfail_writer.c
-vfd_swmr_log_reader_SOURCES=vfd_swmr_log_writer.c
 vfd_swmr_dsetops_reader_SOURCES=vfd_swmr_dsetops_writer.c
 
 vfd_swmr_attrdset_writer_SOURCES=vfd_swmr_attrdset_writer.c
diff --git a/test/vfd_swmr_gperf_writer.c b/test/vfd_swmr_gperf_writer.c
index e21f931..ad2b373 100644
--- a/test/vfd_swmr_gperf_writer.c
+++ b/test/vfd_swmr_gperf_writer.c
@@ -12,6 +12,12 @@
 
 /* Description of this program:
  * This program checks the performance of group creations for VFD SWMR.
+ * It also has an option to turn on the VFD SWMR logging feature and generates
+ * a log message for group creations. The performance test illustration is in
+ * section I. The log feature illustration is in section II.
+ *
+ * I. Performance tests with options
+ *
  * Currently the group creation time, H5Fopen and H5Fclose time are measured.
  * After compiling the program,
  *     ./vfd_swmr_gperf_writer -n 1000 -P -N 5 -q
@@ -29,6 +35,18 @@
  *      The program is run with max_lag = 8, tick_len = 4;
  *      The page buffer size is 16384 bytes. The page size is 8192 bytes.
  *
+ * II. How to generate log message 
+ *
+ *     ./vfd_swmr_gperf_writer -n 100000 -P -L -q 
+ * will generate 100000 groups, each group has one attribute.  It also writes the log message 
+ *      to file "log-test" under the same directory.
+ *      To turn on the log feature, one just needs to provide the log file path as
+ *      indicated by the line init_vfd_swmr_log(&config, "./log-test") in the main
+ *      function. The init_vfd_swmr_log is defined inside the vfd_swmr_common.c.
+ *      The "log-test" should include something like:
+ *      'EOT_PROCESSING_TIME       : 0.040 s: Writer time is 1 milliseconds'
+ *      The standard output of performance measurement can help check the correctness in the "log-test".
+ *
  */
 #define H5F_FRIEND /*suppress error about including H5Fpkg   */
 
@@ -63,6 +81,7 @@ typedef struct {
     uint32_t     max_lag;
     uint32_t     tick_len;
     bool         gperf;
+    bool         glog;
     double       min_gc_time;
     double       max_gc_time;
     double       mean_gc_time;
@@ -84,7 +103,7 @@ typedef struct {
         .file = H5I_INVALID_HID, .one_by_one_sid = H5I_INVALID_HID, .filename = "",                          \
         .filetype = H5T_NATIVE_UINT32, .asteps = 1, .nsteps = 100, .use_vfd_swmr = true,                     \
         .old_style_grp = false, .grp_op_pattern = ' ', .grp_op_test = false, .at_pattern = ' ',              \
-        .attr_test = false, .tick_len = 4, .max_lag = 7, .gperf = false, .min_gc_time = 100.,                \
+        .attr_test = false, .tick_len = 4, .max_lag = 7, .gperf = false, .glog = false, .min_gc_time = 100., \
         .max_gc_time = 0., .mean_gc_time = 0., .total_gc_time = 0., .total_time = 0., .mean_time = 0.,       \
         .fo_total_time = 0., .fc_total_time = 0., .num_attrs = 1, .vlstr_test = false, .ps = 4096,           \
         .pbs = 4096, .nglevels = 0                                                                           \
@@ -95,14 +114,16 @@ usage(const char *progname)
 {
     fprintf(stderr,
             "usage: ./%s -P -n 1000 -N 5 -q (create 1000 groups, each group has 5 attributes)\n"
+            "usage: ./%s -P -L -n 100000 -q (create 100000 groups and generate log message to file 'log-test')\n"
             "Options: \n"
-            " [-P] [-S] [-G] [-t tick_len] [-m max_lag][-B pbs] [-s ps]\n"
+            " [-P] [-S] [-G] [-L] [-t tick_len] [-m max_lag][-B pbs] [-s ps]\n"
             " [-n ngroups] [-l ng_levels] [-O grp_op_pattern]\n"
             " [-N num_attrs] [-V] [-b] [-A at_pattern] [-a steps] [-q]\n"
             "\n"
             "-P:             carry out the performance test\n"
             "-S:             do not use VFD SWMR\n"
             "-G:             old-style type of group\n"
+            "-L:             Turn on the logging feature.\n"
             "-t tick_len:    length of a tick in tenths of a second.\n"
             "-m max_lag:     maximum expected lag(in ticks) between writer and readers\n"
             "-B pbs:         page Buffer Size in bytes:\n"
@@ -174,7 +195,7 @@ usage(const char *progname)
             "              (Don't recommend to use this option for performance test.)\n"
             "-q:             silence printouts, few messages\n"
             "\n",
-            progname);
+            progname,progname);
     exit(EXIT_FAILURE);
 }
 
@@ -203,7 +224,7 @@ state_init(state_t *s, int argc, char **argv)
 
     if (argc == 1)
         usage(s->progname);
-    while ((ch = getopt(argc, argv, "PSGa:bVt:m:B:s:n:qA:N:l:O:")) != -1) {
+    while ((ch = getopt(argc, argv, "PSGLa:bVt:m:B:s:n:qA:N:l:O:")) != -1) {
         switch (ch) {
             case 'P':
                 s->gperf = true;
@@ -214,6 +235,9 @@ state_init(state_t *s, int argc, char **argv)
             case 'G':
                 s->old_style_grp = true;
                 break;
+            case 'L':
+                s->glog = true;
+                break;
             case 'a':
             case 'n':
             case 'N':
@@ -2764,6 +2788,11 @@ main(int argc, char **argv)
     /* config, tick_len, max_lag, writer, flush_raw_data, md_pages_reserved, md_file_path */
     init_vfd_swmr_config(&config, s.tick_len, s.max_lag, writer, FALSE, 128, "./group-shadow");
 
+    /* If the log flag is on, create the log file log-test under the current directory. */
+    if(s.glog == true) 
+        init_vfd_swmr_log(&config, "./log-test");
+
+
     /* If old-style option is chosen, use the earliest file format(H5F_LIBVER_EARLIEST)
      * as the second parameter of H5Pset_libver_bound() that is called by
      * vfd_swmr_create_fapl. Otherwise, the latest file format(H5F_LIBVER_LATEST)
diff --git a/test/vfd_swmr_log_writer.c b/test/vfd_swmr_log_writer.c
deleted file mode 100644
index 06b5654..0000000
--- a/test/vfd_swmr_log_writer.c
+++ /dev/null
@@ -1,2929 +0,0 @@
-/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
- * Copyright by The HDF Group.                                               *
- * All rights reserved.                                                      *
- *                                                                           *
- * This file is part of HDF5.  The full HDF5 copyright notice, including     *
- * terms governing use, modification, and redistribution, is contained in    *
- * the COPYING file, which can be found at the root of the source code       *
- * distribution tree, or in https://www.hdfgroup.org/licenses.               *
- * If you do not have access to either file, you may request a copy from     *
- * help@hdfgroup.org.                                                        *
- * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
-
-/* Description of this program:
- * This program shows an example on how a VFD log file can be written.
- * It is adapted from the group performence test. Most options of the
- * group performance test are still kept.
- * To turn on the log feature, one just needs to provide the log file path as
- * indicated by the line init_vfd_swmr_log(&config, "./log-test") in the main
- * function. The init_vfd_swmr_log is defined inside the vfd_swmr_common.c.
- * For the demo of the log feature,
- * one just needs to do te following:
- * After compiling the program, just run the following line
- *     ./vfd_swmr_log_writer -n 100000 -P -q
- * A VFD SWMR log file "log-test" is generated.
- * The "log-test" should include something like:
- * 'EOT_PROCESSING_TIME       : 0.040 s: Writer time is 1 milliseconds'
- * This program also checks the performance of group creations for VFD SWMR.
- * Currently the group creation time, H5Fopen and H5Fclose time are measured.
- * The standard output can help check the contents in the "log-test".
- *
- */
-#define H5F_FRIEND /*suppress error about including H5Fpkg   */
-
-#include "hdf5.h"
-
-#include "H5Fpkg.h"
-#include "H5HGprivate.h"
-#include "H5VLprivate.h"
-
-#include "testhdf5.h"
-#include "vfd_swmr_common.h"
-
-#ifndef H5_HAVE_WIN32_API
-
-#define VS_ATTR_NAME_LEN 21
-
-#define TIME_PASSED(X, Y)                                                                                    \
-    ((double)((Y.tv_sec - X.tv_sec) * 1000000000 + (Y.tv_nsec - X.tv_nsec))) / 1000000000.0
-
-typedef struct {
-    hid_t        file, filetype, one_by_one_sid;
-    char         filename[PATH_MAX];
-    char         progname[PATH_MAX];
-    unsigned int asteps;
-    unsigned int nsteps;
-    bool         use_vfd_swmr;
-    bool         old_style_grp;
-    char         grp_op_pattern;
-    bool         grp_op_test;
-    char         at_pattern;
-    bool         attr_test;
-    uint32_t     max_lag;
-    uint32_t     tick_len;
-    bool         gperf;
-    double       min_gc_time;
-    double       max_gc_time;
-    double       mean_gc_time;
-    double       total_gc_time;
-    double       total_time;
-    double       mean_time;
-    double       fo_total_time;
-    double       fc_total_time;
-    unsigned int num_attrs;
-    bool         vlstr_test;
-    unsigned int ps;
-    unsigned int pbs;
-    unsigned int nglevels;
-} state_t;
-
-#define ALL_HID_INITIALIZER                                                                                  \
-    (state_t)                                                                                                \
-    {                                                                                                        \
-        .file = H5I_INVALID_HID, .one_by_one_sid = H5I_INVALID_HID, .filename = "",                          \
-        .filetype = H5T_NATIVE_UINT32, .asteps = 1, .nsteps = 100, .use_vfd_swmr = true,                     \
-        .old_style_grp = false, .grp_op_pattern = ' ', .grp_op_test = false, .at_pattern = ' ',              \
-        .attr_test = false, .tick_len = 4, .max_lag = 7, .gperf = false, .min_gc_time = 100.,                \
-        .max_gc_time = 0., .mean_gc_time = 0., .total_gc_time = 0., .total_time = 0., .mean_time = 0.,       \
-        .fo_total_time = 0., .fc_total_time = 0., .num_attrs = 1, .vlstr_test = false, .ps = 4096,           \
-        .pbs = 4096, .nglevels = 0                                                                           \
-    }
-
-static void
-usage(const char *progname)
-{
-    fprintf(stderr,
-            "usage: ./%s -P -n 100000 -q (create 100000 groups, each group has 1 attribute)\n"
-            "Options: \n"
-            " [-P] [-S] [-G] [-t tick_len] [-m max_lag][-B pbs] [-s ps]\n"
-            " [-n ngroups] [-l ng_levels] [-O grp_op_pattern]\n"
-            " [-N num_attrs] [-V] [-b] [-A at_pattern] [-a steps] [-q]\n"
-            "\n"
-            "-P:             carry out the performance test\n"
-            "-S:             do not use VFD SWMR\n"
-            "-G:             old-style type of group\n"
-            "-t tick_len:    length of a tick in tenths of a second.\n"
-            "-m max_lag:     maximum expected lag(in ticks) between writer and readers\n"
-            "-B pbs:         page Buffer Size in bytes:\n"
-            "                The default value is 4K(4096).\n"
-            "-s ps:          page size used by page aggregation, page buffer and \n"
-            "                the metadata file. \n"
-            "-n ngroups:     the number of groups\n"
-            "-l ng_levels:   the number of level of nested groups.  \n"
-            "                If all the groups are under the root group,  \n"
-            "                this number should be 0.\n"
-            "-N num_attrs:   the number of attributes \n"
-            "-V              use variable length string attributes for performance test\n"
-            "-b:             write data in big-endian byte order\n"
-            "                (For the performance test, -V overwrites -b)\n"
-            "-A at_pattern:  `at_pattern' for different attribute tests\n"
-            "-O grp_op_pattern:  `grp_op_pattern' for different group operation tests\n"
-            "-a steps:      `steps` between adding attributes\n"
-            "              (Don't recommend to use this option for performance test.)\n"
-            "-q:             silence printouts, few messages\n"
-            "\n",
-            progname);
-    exit(EXIT_FAILURE);
-}
-
-static bool
-state_init(state_t *s, int argc, char **argv)
-{
-    unsigned long tmp;
-    int           ch;
-    const hsize_t dims  = 1;
-    char *        tfile = NULL;
-    char *        end;
-
-    *s = ALL_HID_INITIALIZER;
-
-    if (H5_basename(argv[0], &tfile) < 0) {
-        printf("H5_basename failed\n");
-        TEST_ERROR;
-    }
-
-    esnprintf(s->progname, sizeof(s->progname), "%s", tfile);
-
-    if (tfile) {
-        HDfree(tfile);
-        tfile = NULL;
-    }
-
-    if (argc == 1)
-        usage(s->progname);
-    while ((ch = getopt(argc, argv, "PSGa:bVt:m:B:s:n:qA:N:l:O:")) != -1) {
-        switch (ch) {
-            case 'P':
-                s->gperf = true;
-                break;
-            case 'S':
-                s->use_vfd_swmr = false;
-                break;
-            case 'G':
-                s->old_style_grp = true;
-                break;
-            case 'a':
-            case 'n':
-            case 'N':
-            case 'l':
-            case 't':
-            case 'm':
-            case 'B':
-            case 's':
-                errno = 0;
-                tmp   = HDstrtoul(optarg, &end, 0);
-                if (end == optarg || *end != '\0') {
-                    printf("couldn't parse `-%c` argument `%s`\n", ch, optarg);
-                    TEST_ERROR;
-                }
-                else if (errno != 0) {
-                    printf("couldn't parse `-%c` argument `%s`\n", ch, optarg);
-                    TEST_ERROR;
-                }
-                else if (tmp > UINT_MAX) {
-                    printf("`-%c` argument `%lu` too large\n", ch, tmp);
-                    TEST_ERROR;
-                }
-
-                if (ch == 'a')
-                    s->asteps = (unsigned)tmp;
-                else if (ch == 'n')
-                    s->nsteps = (unsigned)tmp;
-                else if (ch == 'N')
-                    s->num_attrs = (unsigned)tmp;
-                else if (ch == 'l')
-                    s->nglevels = (unsigned)tmp;
-                else if (ch == 't')
-                    s->tick_len = (unsigned)tmp;
-                else if (ch == 'm')
-                    s->max_lag = (unsigned)tmp;
-                else if (ch == 's')
-                    s->ps = (unsigned)tmp;
-                else if (ch == 'B')
-                    s->pbs = (unsigned)tmp;
-                break;
-            case 'b':
-                s->filetype = H5T_STD_U32BE;
-                break;
-            case 'V':
-                s->vlstr_test = true;
-                break;
-            case 'O':
-                if (HDstrcmp(optarg, "grp-creation") == 0)
-                    s->grp_op_pattern = 'c';
-                else if (HDstrcmp(optarg, "grp-deletion") == 0)
-                    s->grp_op_pattern = 'd';
-                else if (HDstrcmp(optarg, "grp-move") == 0)
-                    s->grp_op_pattern = 'm';
-                else if (HDstrcmp(optarg, "grp-ins-links") == 0)
-                    s->grp_op_pattern = 'i';
-                else if (HDstrcmp(optarg, "grp-del-links") == 0)
-                    s->grp_op_pattern = 'D';
-                else if (HDstrcmp(optarg, "grp-compact-t-dense") == 0)
-                    s->grp_op_pattern = 't';
-                else if (HDstrcmp(optarg, "grp-dense-t-compact") == 0)
-                    s->grp_op_pattern = 'T';
-                else {
-                    printf("Invalid -O argument \"%s\"", optarg);
-                    TEST_ERROR;
-                }
-                break;
-            case 'A':
-                if (HDstrcmp(optarg, "compact") == 0)
-                    s->at_pattern = 'c';
-                else if (HDstrcmp(optarg, "dense") == 0)
-                    s->at_pattern = 'd';
-                else if (HDstrcmp(optarg, "compact-add-to-dense") == 0)
-                    s->at_pattern = 't';
-                else if (HDstrcmp(optarg, "compact-del") == 0)
-                    s->at_pattern = 'C';
-                else if (HDstrcmp(optarg, "dense-del") == 0)
-                    s->at_pattern = 'D';
-                else if (HDstrcmp(optarg, "dense-del-to-compact") == 0)
-                    s->at_pattern = 'T';
-                else if (HDstrcmp(optarg, "modify") == 0)
-                    s->at_pattern = 'M';
-                else if (HDstrcmp(optarg, "add-vstr") == 0)
-                    s->at_pattern = 'v';
-                else if (HDstrcmp(optarg, "remove-vstr") == 0)
-                    s->at_pattern = 'r';
-                else if (HDstrcmp(optarg, "modify-vstr") == 0)
-                    s->at_pattern = 'm';
-                else if (HDstrcmp(optarg, "add-ohr-block") == 0)
-                    s->at_pattern = 'a';
-                else if (HDstrcmp(optarg, "del-ohr-block") == 0)
-                    s->at_pattern = 'R';
-                else {
-                    printf("Invalid -A argument \"%s\"", optarg);
-                    TEST_ERROR;
-                }
-                break;
-            case 'q':
-                verbosity = 0;
-                break;
-            case '?':
-            default:
-                usage(s->progname);
-                break;
-        }
-    }
-    argc -= optind;
-    argv += optind;
-
-    if (s->grp_op_pattern != ' ')
-        s->grp_op_test = true;
-    if (s->at_pattern != ' ')
-        s->attr_test = true;
-
-    if (!s->grp_op_test) {
-        if (s->asteps < 1 || s->asteps > s->nsteps) {
-            printf("attribute interval is out of bounds\n");
-            TEST_ERROR;
-        }
-    }
-
-    if (s->grp_op_test && s->attr_test) {
-        printf("Cannot test both group operation and attribute tests!\n");
-        printf("Attribute tests are ignored.\n");
-    }
-
-    if (argc > 0) {
-        printf("unexpected command-line arguments\n");
-        TEST_ERROR;
-    }
-
-    /* space for attributes */
-    if ((s->one_by_one_sid = H5Screate_simple(1, &dims, &dims)) < 0) {
-        printf("H5Screate_simple failed\n");
-        TEST_ERROR;
-    }
-
-    esnprintf(s->filename, sizeof(s->filename), "vfd_swmr_group.h5");
-
-    return true;
-
-error:
-    if (tfile)
-        HDfree(tfile);
-    return false;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    check_ohr_num_chunk
- *
- * Purpose:     Check if the number of object header chunks is as expected.
- *
- * Parameters:  hid_t oid
- *              HDF5 object ID (in this file: means group ID)
- *
- *              bool one_chunk_ohr
- *              flag to indicate if the object header chunk is 1 or greater
- *              1: true
- *              greater than 1: false
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- *-------------------------------------------------------------------------
- */
-
-static bool
-check_ohr_num_chunk(hid_t g, bool one_chunk_ohr)
-{
-
-    H5O_native_info_t ninfo;
-
-    /* Get the object information */
-    if (H5Oget_native_info(g, &ninfo, H5O_NATIVE_INFO_HDR) < 0) {
-        printf("H5Oget_native_info failed\n");
-        TEST_ERROR;
-    }
-
-    if (true == one_chunk_ohr) {
-        if (ninfo.hdr.nchunks != 1) {
-            printf("Object header should have only one chunk,but it is not.\n");
-            TEST_ERROR;
-        }
-    }
-    else {
-        if (ninfo.hdr.nchunks <= 1) {
-            printf("Object header should have more than one chunk,but it is not.\n");
-            TEST_ERROR;
-        }
-    }
-
-    return true;
-
-error:
-    return false;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    add_attr
- *
- * Purpose:     Add attributes to a group.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              hid_t oid
- *              HDF5 object ID (in this file: means group ID)
- *
- *              unsigned int which
- *              The number of iterations for group creation, use to generate
- *              newly created group name. The group name is "group-which".
- *
- *              unsigned num_attrs
- *              The number of attributes to be created
- *
- *              const char*aname_fmt
- *              The attribute name template used to create unique attribute names.
- *
- *              unsigned int g_which
- *              This parameter is used to generate correct group name in a key
- *              debugging message.
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- *-------------------------------------------------------------------------
- */
-
-static bool
-add_attr(state_t *s, hid_t oid, unsigned int which, unsigned num_attrs, const char *aname_fmt,
-         unsigned int g_which)
-{
-
-    char     attrname[VS_ATTR_NAME_LEN];
-    unsigned u;
-    unsigned attr_value;
-    hid_t    aid    = H5I_INVALID_HID;
-    hid_t    amtype = H5I_INVALID_HID;
-    hid_t    atype  = s->filetype;
-    hid_t    sid    = s->one_by_one_sid;
-
-    /* Need to obtain native datatype for H5Aread */
-    if ((amtype = H5Tget_native_type(atype, H5T_DIR_ASCEND)) < 0) {
-        printf("H5Tget_native_type failed\n");
-        TEST_ERROR;
-    }
-
-    for (u = 0; u < num_attrs; u++) {
-
-        /* Create attribute */
-        /* Construct attribute name like attr-0-0 */
-        HDsprintf(attrname, aname_fmt, which, u);
-        if ((aid = H5Acreate2(oid, attrname, atype, sid, H5P_DEFAULT, H5P_DEFAULT)) < 0) {
-            printf("H5Acreate2 failed\n");
-            TEST_ERROR;
-        }
-
-        attr_value = u + which;
-
-        dbgf(1, "setting attribute %s on group %u to %u\n", attrname, g_which, u + which);
-
-        /* Write data into the attribute */
-        if (H5Awrite(aid, amtype, &attr_value) < 0) {
-            printf("H5Awrite failed\n");
-            TEST_ERROR;
-        }
-
-        /* Close attribute */
-        if (H5Aclose(aid) < 0) {
-            printf("H5Aclose failed\n");
-            TEST_ERROR;
-        }
-
-        /* If coming to an "object header continuation block" test,
-         * we need to check if this test behaves as expected. */
-        if (s->at_pattern == 'a' || s->at_pattern == 'R') {
-            if (false == check_ohr_num_chunk(oid, false)) {
-                printf("An object header continuation block should be created. \n");
-                printf("But it is not.\n");
-                TEST_ERROR;
-            }
-        }
-
-    } /* end for */
-
-    if (H5Tclose(amtype) < 0) {
-        TEST_ERROR;
-    }
-
-    return true;
-
-error:
-    H5E_BEGIN_TRY
-    {
-        H5Aclose(aid);
-        H5Tclose(amtype);
-    }
-    H5E_END_TRY;
-
-    return false;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    add_vlstr_attr
- *
- * Purpose:     Add a variable length string  attribute to a group.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              hid_t g
- *              HDF5 object ID (in this file: means group ID)
- *
- *              unsigned int which
- *              The number of iterations for group creation, use to generate
- *              newly created group and attribute names.
- *              The group name is "group-which" and the attribute name
- *              is "attr-which".
- *
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is for the "vstr" test.
- *-------------------------------------------------------------------------
- */
-
-static bool
-add_vlstr_attr(state_t *s, hid_t g, unsigned int which)
-{
-
-    hid_t aid   = H5I_INVALID_HID;
-    hid_t atype = H5I_INVALID_HID;
-    char  name[VS_ATTR_NAME_LEN];
-    char *astr_val = NULL;
-    hid_t sid      = s->one_by_one_sid;
-
-    /* Allocate buffer for the VL string value */
-    astr_val = HDmalloc(VS_ATTR_NAME_LEN);
-    if (astr_val == NULL) {
-        printf("Allocate memory for VL string failed.\n");
-        TEST_ERROR;
-    }
-
-    /* Assign the VL string value and the attribute name.. */
-    HDsprintf(astr_val, "%u", which);
-    esnprintf(name, sizeof(name), "attr-%u", which);
-
-    dbgf(1, "setting attribute %s on group %u to %u\n", name, which, which);
-
-    /* Create a datatype to refer to. */
-    if ((atype = H5Tcopy(H5T_C_S1)) < 0) {
-        printf("Cannot create variable length datatype.\n");
-        TEST_ERROR;
-    }
-
-    if (H5Tset_size(atype, H5T_VARIABLE) < 0) {
-        printf("Cannot set variable length datatype.\n");
-        TEST_ERROR;
-    }
-
-    /* Generate the VL string attribute.*/
-    if ((aid = H5Acreate2(g, name, atype, sid, H5P_DEFAULT, H5P_DEFAULT)) < 0) {
-        printf("H5Acreate2 failed.\n");
-        TEST_ERROR;
-    }
-
-    if (H5Awrite(aid, atype, &astr_val) < 0) {
-        printf("H5Awrite failed.\n");
-        TEST_ERROR;
-    }
-
-    if (H5Tclose(atype) < 0) {
-        printf("H5Tclose() failed\n");
-        TEST_ERROR;
-    }
-    if (H5Aclose(aid) < 0) {
-        printf("H5Aclose() failed\n");
-        TEST_ERROR;
-    }
-
-    HDfree(astr_val);
-
-    return true;
-
-error:
-    H5E_BEGIN_TRY
-    {
-        H5Aclose(aid);
-        H5Tclose(atype);
-    }
-    H5E_END_TRY;
-
-    if (astr_val)
-        HDfree(astr_val);
-
-    return false;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    add_vlstr_attrs
- *
- * Purpose:     Add variable length string attributes to a group.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              hid_t g
- *              HDF5 object ID (in this file: means group ID)
- *
- *              unsigned int which
- *              The number of iterations for group creation, use to generate
- *              newly created group and attribute names.
- *              The group name is "group-which".  The attribute names
- *              are "attr-which","attr-which+1"....
- *
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is for the performance test that has the VL string type.
- *-------------------------------------------------------------------------
- */
-
-static bool
-add_vlstr_attrs(state_t *s, hid_t g, unsigned int which, unsigned int num_attrs)
-{
-    unsigned u;
-    bool     ret_value = true;
-    for (u = 0; u < num_attrs; u++) {
-        ret_value = add_vlstr_attr(s, g, u + which);
-        if (ret_value == false)
-            break;
-    }
-
-    return ret_value;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    add_default_group_attr
- *
- * Purpose:     Add an attribute to a group.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              hid_t g
- *              HDF5 object ID (in this file: means group ID)
- *
- *              unsigned int which
- *              The number of iterations for group creation, use to generate
- *              newly created group and attribute names.
- *              The group name is "group-which" and the attribute name
- *              is "attr-which".
- *
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This function is used for the "dense" storage test.
- *              It is also used by the group-only, "add-ohr-block"
- *              and "del-ohr-block" tests.
- *-------------------------------------------------------------------------
- */
-
-static bool
-add_default_group_attr(state_t *s, hid_t g, unsigned int which)
-{
-
-    const char *aname_format = "attr-%u-%u";
-
-    /* Note: the number of attributes can be configurable,
-     * the default number of attribute is 1.
-     */
-    /* If the vl string attribute type is chosen. */
-    if (s->vlstr_test == true)
-        return add_vlstr_attrs(s, g, which, s->num_attrs);
-    else
-        return add_attr(s, g, which, s->num_attrs, aname_format, which);
-}
-
-/*-------------------------------------------------------------------------
- * Function:    del_one_attr
- *
- * Purpose:     delete one attribute in a group.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              hid_t obj_id
- *              HDF5 object ID (in this file: means group ID)
- *
- *              bool is_dense
- *              if the deleted attribute is for checking the dense storage
- *
- *              bool is_vl_or_ohrc
- *              if the deleted attribute is a VL string or for object header
- *              continuation check test
- *
- *              unsigned int which
- *              The number of iterations for group creation, use to generate
- *              newly created group and attribute names.
- *              The group name is "group-which" and the attribute names
- *              according to if this attribute is a VL string or for checking
- *              the dense storage or the storage transition from dense to
- *              compact.
- *
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- *-------------------------------------------------------------------------
- */
-
-static bool
-del_one_attr(state_t *s, hid_t obj_id, bool is_dense, bool is_vl_or_ohrc, unsigned int which)
-{
-
-    char attrname[VS_ATTR_NAME_LEN];
-
-    /*attribute name template for the dense storage related deletion operation */
-    const char *aname_format_d = "attr-d-%u-%u";
-
-    /*attribute name template used for general attribute deletion operation */
-    const char *aname_format = "attr-%u-%u";
-
-    /*attribute name template used for VL string attribute deletion
-     * or object header continuation check operations */
-    const char *aname_format_vl = "attr-%u";
-
-    dbgf(2, "writer: coming to delete the attribute.\n");
-
-    /* Construct the attribute name */
-    if (is_dense == true)
-        HDsprintf(attrname, aname_format_d, which, 0);
-    else if (is_vl_or_ohrc == true)
-        HDsprintf(attrname, aname_format_vl, which, 0);
-    else
-        HDsprintf(attrname, aname_format, which, 0);
-
-    /* Delete the attribute */
-    if (H5Adelete(obj_id, attrname) < 0) {
-        printf("H5Adelete() failed\n");
-        TEST_ERROR;
-    }
-
-    /* If coming to an "object header continuation block" test,
-     * we need to check if this test behaves as expected. */
-    if (s->at_pattern == 'R') {
-        if (false == check_ohr_num_chunk(obj_id, true)) {
-            printf("The object header chunk should not continue. \n");
-            TEST_ERROR;
-        }
-    }
-    return true;
-
-error:
-    return false;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    add_del_vlstr_attr
- *
- * Purpose:     Add a variable length string attribute
- *              then delete this attribute in this a group.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              hid_t g
- *              HDF5 object ID (in this file: means group ID)
- *
- *              unsigned int which
- *              The number of iterations for group creation, use to generate
- *              newly created group and attribute names.
- *              The group name is "group-which" and the attribute name
- *              is "attr-which".
- *
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is for the "remove-vstr" test.
- *-------------------------------------------------------------------------
- */
-
-static bool
-add_del_vlstr_attr(state_t *s, hid_t g, unsigned int which)
-{
-
-    bool ret_value = false;
-
-    /* Add a VL string attribute then delete it. */
-    ret_value = add_vlstr_attr(s, g, which);
-    if (ret_value == true)
-        ret_value = del_one_attr(s, g, false, true, which);
-
-    return ret_value;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    modify_attr
- *
- * Purpose:     Modify the value of an attribute in a group.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              hid_t g
- *              HDF5 object ID (in this file: means group ID)
- *
- *              const char*aname_fmt
- *              The attribute name template used to create unique attribute names.
- *
- *              unsigned int which
- *              The number of iterations for group creation, use to generate
- *              newly created group name. The group name is "group-which".
- *
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- *-------------------------------------------------------------------------
- */
-
-static bool
-modify_attr(state_t *s, hid_t g, const char *aname_fmt, unsigned int which)
-{
-
-    char         attrname[VS_ATTR_NAME_LEN];
-    hid_t        aid    = H5I_INVALID_HID;
-    hid_t        amtype = H5I_INVALID_HID;
-    unsigned int modify_value;
-
-    HDsprintf(attrname, aname_fmt, which, 0);
-    if ((aid = H5Aopen(g, attrname, H5P_DEFAULT)) < 0) {
-        printf("H5Aopen failed\n");
-        TEST_ERROR;
-    }
-
-    if ((amtype = H5Tget_native_type(s->filetype, H5T_DIR_ASCEND)) < 0) {
-        printf("H5Tget_native_type failed\n");
-        TEST_ERROR;
-    }
-
-    /* Make a large number to verify the change easily */
-    modify_value = which + 10000;
-
-    if (H5Awrite(aid, amtype, &modify_value) < 0) {
-        printf("H5Awrite failed\n");
-        TEST_ERROR;
-    }
-    if (H5Tclose(amtype) < 0) {
-        printf("H5Tclose failed\n");
-        TEST_ERROR;
-    }
-    if (H5Aclose(aid) < 0) {
-        printf("H5Aclose failed\n");
-        TEST_ERROR;
-    }
-
-    return true;
-error:
-    H5E_BEGIN_TRY
-    {
-        H5Aclose(aid);
-        H5Tclose(aid);
-    }
-    H5E_END_TRY;
-
-    return false;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    modify_vlstr_attr
- *
- * Purpose:     Modify the value of an VL string attribute in a group.
- *
- * Parameters:
- *              hid_t g
- *              HDF5 object ID (in this file: means group ID)
- *
- *              unsigned int which
- *              The number of iterations for group creation, use to generate
- *              newly created group name. The group name is "group-which".
- *
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- *-------------------------------------------------------------------------
- */
-
-static bool
-modify_vlstr_attr(hid_t g, unsigned int which)
-{
-
-    hid_t aid   = H5I_INVALID_HID;
-    hid_t atype = H5I_INVALID_HID;
-    char  name[VS_ATTR_NAME_LEN];
-    char *astr_val = NULL;
-
-    astr_val = HDmalloc(VS_ATTR_NAME_LEN);
-    if (astr_val == NULL) {
-        printf("Allocate memory for VL string failed.\n");
-        TEST_ERROR;
-    }
-
-    /* Change the VL string value and create the attribute name. */
-    HDsprintf(astr_val, "%u%c", which, 'A');
-    esnprintf(name, sizeof(name), "attr-%u", which);
-
-    dbgf(1, "setting attribute %s on group %u to %u\n", name, which, which);
-
-    /* Create a datatype to refer to. */
-    if ((atype = H5Tcopy(H5T_C_S1)) < 0) {
-        printf("Cannot create variable length datatype.\n");
-        TEST_ERROR;
-    }
-
-    if (H5Tset_size(atype, H5T_VARIABLE) < 0) {
-        printf("Cannot set variable length datatype.\n");
-        TEST_ERROR;
-    }
-
-    /* Open this attribute. */
-    if ((aid = H5Aopen(g, name, H5P_DEFAULT)) < 0) {
-        printf("H5Aopen failed.\n");
-        TEST_ERROR;
-    }
-
-    dbgf(1, "The modified VL string value  is  %s \n", astr_val);
-
-    if (H5Awrite(aid, atype, &astr_val) < 0) {
-        printf("H5Awrite failed.\n");
-        TEST_ERROR;
-    }
-
-    if (H5Tclose(atype) < 0) {
-        printf("H5Tclose() failed\n");
-        TEST_ERROR;
-    }
-
-    if (H5Aclose(aid) < 0) {
-        printf("H5Aclose() failed\n");
-        TEST_ERROR;
-    }
-
-    HDfree(astr_val);
-
-    return true;
-
-error:
-    H5E_BEGIN_TRY
-    {
-        H5Aclose(aid);
-        H5Tclose(atype);
-    }
-    H5E_END_TRY;
-
-    if (astr_val)
-        HDfree(astr_val);
-
-    return false;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    add_modify_vlstr_attr
- *
- * Purpose:     Add a variable length string attribute
- *              then modify this attribute in the group.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              hid_t g
- *              HDF5 object ID (in this file: means group ID)
- *
- *              unsigned int which
- *              The number of iterations for group creation, use to generate
- *              newly created group and attribute names.
- *              The group name is "group-which" and the attribute name
- *              is "attr-which".
- *
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is for the "modify-vstr" test.
- *-------------------------------------------------------------------------
- */
-
-static bool
-add_modify_vlstr_attr(state_t *s, hid_t g, unsigned int which)
-{
-
-    bool ret_value = false;
-    ret_value      = add_vlstr_attr(s, g, which);
-    if (true == ret_value)
-        ret_value = modify_vlstr_attr(g, which);
-
-    return ret_value;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    add_attrs_compact
- *
- * Purpose:     Add some attributes to the group.
- *              the number of attributes should be the maximal number of
- *              attributes that the compact storage can hold
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              hid_t g
- *              HDF5 object ID (in this file: means group ID)
- *
- *              hid_t gcpl
- *              Object creation property list ID
- *
- *              unsigned int which
- *              The number of iterations for group creation, use to generate
- *              newly created group and attribute names.
- *              The group name is "group-which" and the attribute name
- *              is "attr-which".
- *
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is for the "modify-vstr" test.
- *              For attribute compact/dense storage, check the reference
- *              manual of H5Pget_attr_phase_change.
- *-------------------------------------------------------------------------
- */
-
-static bool
-add_attrs_compact(state_t *s, hid_t g, hid_t gcpl, unsigned int which)
-{
-
-    unsigned    max_compact  = 0;
-    unsigned    min_dense    = 0;
-    const char *aname_format = "attr-%u-%u";
-
-    if (s->old_style_grp)
-        max_compact = 2;
-    else {
-        /* Obtain the maximal number of attributes to be stored in compact
-         * storage and the minimal number of attributes to be stored in
-         * dense storage. */
-        if (H5Pget_attr_phase_change(gcpl, &max_compact, &min_dense) < 0) {
-            printf("H5Pget_attr_phase_change() failed\n");
-            TEST_ERROR;
-        }
-    }
-
-    /* Add max_compact attributes, these attributes are stored in
-     * compact storage. */
-    return add_attr(s, g, which, max_compact, aname_format, which);
-
-error:
-    return false;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    add_attrs_compact_dense
- *
- * Purpose:     Add some attributes to the group.
- *              First, the number of attributes should be the maximal number
- *              of attributes that the compact storage can hold.
- *              Then,  add another atribute, the storage becomes dense.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              hid_t g
- *              HDF5 object ID (in this file: means group ID)
- *
- *              hid_t gcpl
- *              Object creation property list ID
- *
- *              unsigned int which
- *              The number of iterations for group creation, use to generate
- *              newly created group and attribute names.
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is for the "compact-to-dense" test.
- *              For attribute compact/dense storage, check the reference
- *              manual of H5Pget_attr_phase_change.
- *-------------------------------------------------------------------------
- */
-
-static bool
-add_attrs_compact_dense(state_t *s, hid_t g, hid_t gcpl, unsigned int which)
-{
-
-    unsigned    max_compact  = 0;
-    unsigned    min_dense    = 0;
-    const char *aname_format = "attr-d-%u-%u";
-    bool        ret_value    = false;
-
-    if (H5Pget_attr_phase_change(gcpl, &max_compact, &min_dense) < 0) {
-        printf("H5Pget_attr_phase_change failed\n");
-        TEST_ERROR;
-    }
-
-    /* Add attributes, until just before converting to dense storage */
-    ret_value = add_attrs_compact(s, g, gcpl, which);
-
-    /* Add another attribute, the storage becomes dense. */
-    if (ret_value == true)
-        ret_value = add_attr(s, g, which + max_compact, 1, aname_format, which);
-
-    return ret_value;
-
-error:
-    return false;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    del_attrs_compact_dense_compact
- *
- * Purpose:     delete some attributes in the group.
- *              The number of attributes are deleted in such a way
- *              that the attribute storage changes from compact to
- *              dense then to compact again.
- *
- * Parameters:  hid_t g
- *              HDF5 object ID (in this file: means group ID)
- *
- *              hid_t gcpl
- *              Object creation property list ID
- *
- *              unsigned int which
- *              The number of iterations for group creation, use to generate
- *              newly created group and attribute names.
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is an internal function used by the
- *              "dense-del-to-compact" test.
- *              For attribute compact/dense storage, check the reference
- *              manual of H5Pget_attr_phase_change.
- *-------------------------------------------------------------------------
- */
-
-static bool
-del_attrs_compact_dense_compact(hid_t obj_id, hid_t gcpl, unsigned int which)
-{
-
-    unsigned max_compact = 0;
-    unsigned min_dense   = 0;
-    unsigned u           = 0;
-
-    char        attrname[VS_ATTR_NAME_LEN];
-    const char *aname_format  = "attr-%u-%u";
-    const char *adname_format = "attr-d-%u-%u";
-
-    /* Obtain the maximal number of attributes to be stored in compact
-     * storage and the minimal number of attributes to be stored in
-     * dense storage. */
-    if (H5Pget_attr_phase_change(gcpl, &max_compact, &min_dense) < 0) {
-        printf("H5Pget_attr_phase_change failed\n");
-        TEST_ERROR;
-    }
-    u = max_compact + 1;
-
-    /* delete a number of attributes so that the attribute storage just becomes dense.*/
-    for (u--; u >= (min_dense - 1); u--) {
-        HDsprintf(attrname, aname_format, which, max_compact - u);
-        if (H5Adelete(obj_id, attrname) < 0) {
-            printf("H5Adelete failed\n");
-            TEST_ERROR;
-        }
-    }
-
-    /* The writer deletes another attribute, the storage is
-     * still dense. However, the attribute to be deleted
-     * doesn't follow the previous for loop. It may be
-     * in different location in the object header. Just add
-     * a litter variation to check if this operation is successful.
-     * The attribute name to be deleted is attr-max_compact+which-0
-     */
-
-    HDsprintf(attrname, adname_format, max_compact + which, 0);
-    if (H5Adelete(obj_id, attrname) < 0) {
-        printf("H5Adelete failed\n");
-        TEST_ERROR;
-    }
-
-    return true;
-
-error:
-    return false;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    add_del_attrs_compact
- *
- * Purpose:     Add some attributes to the group and then delete one attribute.
- *              First, the number of attributes to be added should be the
- *              maximal number of attributes that the compact storage can hold.
- *              Then,  delete one atribute, the storage is still compact.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              hid_t g
- *              HDF5 object ID (in this file: means group ID)
- *
- *              hid_t gcpl
- *              Object creation property list ID
- *
- *              unsigned int which
- *              The number of iterations for group creation, use to generate
- *              newly created group and attribute names.
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is for the "compact-del" test.
- *              For attribute compact/dense storage, check the reference
- *              manual of H5Pget_attr_phase_change.
- *-------------------------------------------------------------------------
- */
-
-static bool
-add_del_attrs_compact(state_t *s, hid_t g, hid_t gcpl, unsigned int which)
-{
-
-    bool ret_value = false;
-    ret_value      = add_attrs_compact(s, g, gcpl, which);
-    if (ret_value == true) {
-        dbgf(2, "writer: before deleting the attribute.\n");
-        ret_value = del_one_attr(s, g, false, false, which);
-    }
-
-    return ret_value;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    add_del_attrs_compact_dense
- *
- * Purpose:     Add some attributes to the group and then delete one attribute.
- *              First, the number of attributes to be added exceeds
- *              the maximal number of attributes that the compact storage can hold.
- *              The storage changes from compact to dense.
- *              Then,  delete one atribute, the storage is still dense.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              hid_t g
- *              HDF5 object ID (in this file: means group ID)
- *
- *              hid_t gcpl
- *              Object creation property list ID
- *
- *              unsigned int which
- *              The number of iterations for group creation, use to generate
- *              newly created group and attribute names.
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is for the "dense-del" test.
- *              For attribute compact/dense storage, check the reference
- *              manual of H5Pget_attr_phase_change.
- *-------------------------------------------------------------------------
- */
-
-static bool
-add_del_attrs_compact_dense(state_t *s, hid_t g, hid_t gcpl, unsigned int which)
-{
-
-    bool     ret_value   = false;
-    unsigned max_compact = 0;
-    unsigned min_dense   = 0;
-
-    if (H5Pget_attr_phase_change(gcpl, &max_compact, &min_dense) < 0) {
-        printf("H5Pget_attr_phase_change failed\n");
-        TEST_ERROR;
-    }
-
-    ret_value = add_attrs_compact_dense(s, g, gcpl, which);
-    if (ret_value == true)
-        ret_value = del_one_attr(s, g, true, false, which + max_compact);
-
-    return ret_value;
-
-error:
-    return false;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    add_del_attrs_compact_dense_compact
- *
- * Purpose:     Add attributes to the group and then delete some of them.
- *              First, the number of attributes to be added exceeds
- *              the maximal number of attributes that the compact storage can hold.
- *              The storage changes from compact to dense.
- *              Then,  delete some attributes, the storage changes from
- *              dense to compact again.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              hid_t g
- *              HDF5 object ID (in this file: means group ID)
- *
- *              hid_t gcpl
- *              Object creation property list ID
- *
- *              unsigned int which
- *              The number of iterations for group creation, use to generate
- *              newly created group and attribute names.
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is for the "dense-del-to-compact" test.
- *              For attribute compact/dense storage, check the reference
- *              manual of H5Pget_attr_phase_change.
- *-------------------------------------------------------------------------
- */
-
-static bool
-add_del_attrs_compact_dense_compact(state_t *s, hid_t g, hid_t gcpl, unsigned int which)
-{
-
-    bool ret_value = false;
-    ret_value      = add_attrs_compact_dense(s, g, gcpl, which);
-    if (ret_value == true)
-        ret_value = del_attrs_compact_dense_compact(g, gcpl, which);
-
-    return ret_value;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    add_modify_default_group_attr
- *
- * Purpose:     Add an attribute then modify the value to a group.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              hid_t g
- *              HDF5 object ID (in this file: means group ID)
- *
- *              unsigned int which
- *              The number of iterations for group creation, use to generate
- *              newly created group and attribute names.
- *              The group name is "group-which" and the attribute name
- *              is "attr-which".
- *
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This function is used for the "modify" test.
- *-------------------------------------------------------------------------
- */
-
-static bool
-add_modify_default_group_attr(state_t *s, hid_t g, unsigned int which)
-{
-
-    bool        ret_value    = false;
-    const char *aname_format = "attr-%u";
-    ret_value                = add_default_group_attr(s, g, which);
-    if (ret_value == true)
-        ret_value = modify_attr(s, g, aname_format, which);
-    return ret_value;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    del_ohr_block_attr
- *
- * Purpose:     Add an attribute to force creation of object header
- *              continuation block and remove this attribute to delete
- *              the object header continuation block
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              hid_t g
- *              HDF5 object ID (in this file: means group ID)
- *
- *              unsigned int which
- *              The number of iterations for group creation, use to generate
- *              newly created group and attribute names.
- *              The group name is "group-which" and the attribute name
- *              is "attr-which".
- *
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This function is used for the
- *              "deletion of object header continuation block" test.
- *-------------------------------------------------------------------------
- */
-
-static bool
-del_ohr_block_attr(state_t *s, hid_t g, unsigned int which)
-{
-
-    bool ret_value = false;
-    ret_value      = add_default_group_attr(s, g, which);
-    if (ret_value == true)
-        ret_value = del_one_attr(s, g, false, true, which);
-    return ret_value;
-}
-/*-------------------------------------------------------------------------
- * Function:    add_group_attribute
- *
- * Purpose:     Check the attribute test pattern and then call the
- *              correponding test function..
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              hid_t g
- *              HDF5 object ID (in this file: means group ID)
- *
- *              hid_t gcpl
- *              Object creation property list ID
- *
- *              unsigned int which
- *              The number of iterations for group creation, use to generate
- *              newly created group and attribute names.
- *
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is called by the write_group() function.
- *-------------------------------------------------------------------------
- */
-
-static bool
-add_group_attribute(state_t *s, hid_t g, hid_t gcpl, unsigned int which)
-{
-
-    bool ret_value    = false;
-    char test_pattern = s->at_pattern;
-
-    switch (test_pattern) {
-        case 'c':
-            ret_value = add_attrs_compact(s, g, gcpl, which);
-            break;
-        case 't':
-            ret_value = add_attrs_compact_dense(s, g, gcpl, which);
-            break;
-        case 'C':
-            ret_value = add_del_attrs_compact(s, g, gcpl, which);
-            break;
-        case 'D':
-            ret_value = add_del_attrs_compact_dense(s, g, gcpl, which);
-            break;
-        case 'T':
-            ret_value = add_del_attrs_compact_dense_compact(s, g, gcpl, which);
-            break;
-        case 'M':
-            ret_value = add_modify_default_group_attr(s, g, which);
-            break;
-        case 'v':
-            ret_value = add_vlstr_attr(s, g, which);
-            break;
-        case 'r':
-            ret_value = add_del_vlstr_attr(s, g, which);
-            break;
-        case 'm':
-            ret_value = add_modify_vlstr_attr(s, g, which);
-            break;
-        case 'R':
-            ret_value = del_ohr_block_attr(s, g, which);
-            break;
-        case 'a':
-        case 'd':
-        case ' ':
-        default:
-            ret_value = add_default_group_attr(s, g, which);
-            break;
-    }
-    return ret_value;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    write_group
- *
- * Purpose:     Create a group and carry out attribute operations(add,delete etc.)
- *              according to the attribute test pattern.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              unsigned int which
- *              The number of iterations for group creation
- *
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is called by the main() function.
- *-------------------------------------------------------------------------
- */
-
-static bool
-write_group(state_t *s, unsigned int which)
-{
-    char            name[sizeof("/group-9999999999")];
-    hid_t           g       = H5I_INVALID_HID;
-    hid_t           dummy_d = H5I_INVALID_HID;
-    hid_t           gcpl    = H5I_INVALID_HID;
-    bool            result  = true;
-    H5G_info_t      group_info;
-    struct timespec start_time, end_time;
-    double          temp_time;
-
-    if (which >= s->nsteps) {
-        printf("Number of created groups is out of bounds\n");
-        TEST_ERROR;
-    }
-
-    esnprintf(name, sizeof(name), "/group-%u", which);
-
-    if (s->old_style_grp)
-        gcpl = H5P_DEFAULT;
-    else {
-        gcpl = H5Pcreate(H5P_GROUP_CREATE);
-        if (gcpl < 0) {
-            printf("H5Pcreate failed\n");
-            TEST_ERROR;
-        }
-
-        /* If we test the dense storage, change the attribute phase. */
-        if (s->at_pattern == 'd') {
-            if (H5Pset_attr_phase_change(gcpl, 0, 0) < 0) {
-                printf("H5Pset_attr_phase_change failed for the dense storage.\n");
-                TEST_ERROR;
-            }
-        }
-    }
-
-    if (s->gperf) {
-
-        if (HDclock_gettime(CLOCK_MONOTONIC, &start_time) == -1) {
-
-            fprintf(stderr, "HDclock_gettime failed");
-
-            TEST_ERROR;
-        }
-    }
-
-    if ((g = H5Gcreate2(s->file, name, H5P_DEFAULT, gcpl, H5P_DEFAULT)) < 0) {
-        printf("H5Gcreate2 failed\n");
-        TEST_ERROR;
-    }
-
-    if (s->gperf) {
-
-        if (HDclock_gettime(CLOCK_MONOTONIC, &end_time) == -1) {
-
-            fprintf(stderr, "HDclock_gettime failed");
-
-            TEST_ERROR;
-        }
-
-        temp_time = TIME_PASSED(start_time, end_time);
-        if (temp_time < s->min_gc_time)
-            s->min_gc_time = temp_time;
-        if (temp_time > s->max_gc_time)
-            s->max_gc_time = temp_time;
-        s->total_gc_time += temp_time;
-    }
-
-    /* We need to create a dummy dataset for the object header continuation block test. */
-    if (s->at_pattern == 'a' || s->at_pattern == 'R') {
-        if ((dummy_d = H5Dcreate2(g, "Dataset", H5T_NATIVE_INT, s->one_by_one_sid, H5P_DEFAULT, H5P_DEFAULT,
-                                  H5P_DEFAULT)) < 0) {
-            printf("H5Dcreate2 failed\n");
-            TEST_ERROR;
-        }
-    }
-    /* We only need to check the first group */
-    if (which == 0) {
-        if (H5Gget_info(g, &group_info) < 0) {
-            printf("H5Gget_info failed\n");
-            TEST_ERROR;
-        }
-
-        if (s->old_style_grp) {
-            if (group_info.storage_type != H5G_STORAGE_TYPE_SYMBOL_TABLE) {
-                printf("Old-styled group test: but the group is not in old-style. \n");
-                TEST_ERROR;
-            }
-            dbgf(2, "Writer: group is created with the old-style.\n");
-        }
-        else {
-            if (group_info.storage_type == H5G_STORAGE_TYPE_SYMBOL_TABLE) {
-                printf("The created group should NOT be in old-style . \n");
-                TEST_ERROR;
-            }
-            dbgf(2, "Writer: group is created with the new-style.\n");
-        }
-    }
-
-    /* If coming to an "object header continuation block" test,
-     * we need to check if this test behaves as expected. */
-    if (s->at_pattern == 'a' || s->at_pattern == 'R') {
-        if (false == check_ohr_num_chunk(g, true)) {
-            printf("An object header continuation block should NOT be created. \n");
-            printf("But it is created.\n");
-            TEST_ERROR;
-        }
-    }
-
-    /* Then carry out the attribute operation. */
-    if (s->asteps != 0 && which % s->asteps == 0)
-        result = add_group_attribute(s, g, gcpl, which);
-
-    if (s->at_pattern == 'a' || s->at_pattern == 'R') {
-        if (H5Dclose(dummy_d) < 0) {
-            printf("H5Dclose failed\n");
-            TEST_ERROR;
-        }
-    }
-
-    if (H5Gclose(g) < 0) {
-        printf("H5Gclose failed\n");
-        TEST_ERROR;
-    }
-
-    if (!s->old_style_grp && H5Pclose(gcpl) < 0) {
-        printf("H5Pclose failed\n");
-        TEST_ERROR;
-    }
-
-    return result;
-
-error:
-
-    H5E_BEGIN_TRY
-    {
-        H5Gclose(g);
-        if (s->at_pattern == 'a' || s->at_pattern == 'R')
-            H5Dclose(dummy_d);
-        if (!s->old_style_grp)
-            H5Pclose(gcpl);
-    }
-    H5E_END_TRY;
-
-    return false;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    create_group_id
- *
- * Purpose:     Create a group and return the group ID.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              unsigned int which
- *              The number of iterations for group creation
- *              This is used to generate the group name.
- *
- *              bool dense_to_compact
- *              true if this function is used to test the transition from dense to
- *              compact, false if the test is from compact to dense.
- *
- * Return:      Success:    the group ID
- *              Failure:    -1
- *
- * Note:        Only used by testing the link storage transit functions.
- *-------------------------------------------------------------------------
- */
-
-static hid_t
-create_group_id(state_t *s, unsigned int which, bool dense_to_compact)
-{
-
-    char       name[sizeof("/group-9999999999")];
-    hid_t      g    = H5I_INVALID_HID;
-    hid_t      gcpl = H5I_INVALID_HID;
-    H5G_info_t group_info;
-
-    if (which >= s->nsteps) {
-        printf("Number of created groups is out of bounds\n");
-        TEST_ERROR;
-    }
-
-    gcpl = H5Pcreate(H5P_GROUP_CREATE);
-    if (gcpl < 0) {
-        printf("H5Pcreate failed\n");
-        TEST_ERROR;
-    }
-
-    if (dense_to_compact) {
-        if (H5Pset_link_phase_change(gcpl, 2, 2) < 0) {
-            printf("H5Pset_link_phase_change failed for dense to compact.\n");
-            TEST_ERROR;
-        }
-    }
-    else {
-        if (H5Pset_link_phase_change(gcpl, 1, 1) < 0) {
-            printf("H5Pset_attr_phase_change failed for compact to dense.\n");
-            TEST_ERROR;
-        }
-    }
-
-    esnprintf(name, sizeof(name), "/group-%u", which);
-    if ((g = H5Gcreate2(s->file, name, H5P_DEFAULT, gcpl, H5P_DEFAULT)) < 0) {
-        printf("H5Gcreate2 failed\n");
-        TEST_ERROR;
-    }
-
-    if (H5Gget_info(g, &group_info) < 0) {
-        printf("H5Gget_info failed\n");
-        TEST_ERROR;
-    }
-
-    /* The storage type should always be compact when a group is created. */
-    if (group_info.storage_type != H5G_STORAGE_TYPE_COMPACT) {
-        printf("New-style group link storage test:. \n");
-        printf("    still be compact after group creation. \n");
-        TEST_ERROR;
-    }
-
-    if (H5Pclose(gcpl) < 0) {
-        printf("H5Pclose failed\n");
-        TEST_ERROR;
-    }
-
-    return g;
-
-error:
-
-    H5E_BEGIN_TRY
-    {
-        H5Pclose(gcpl);
-    }
-    H5E_END_TRY;
-
-    return -1;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    close_group_id
- *
- * Purpose:     Verify is a group is closed successfully.
- *
- * Parameters:  hid_t g
- *              The ID of the group to be closed.
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is used by the link storage transit functions.
- *-------------------------------------------------------------------------
- */
-
-static bool
-close_group_id(hid_t g)
-{
-
-    if (H5Gclose(g) < 0) {
-        printf("H5Gclose failed\n");
-        TEST_ERROR;
-    }
-
-    return true;
-
-error:
-    return false;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    create_group
- *
- * Purpose:     Create a group
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              unsigned int which
- *              The number of iterations for group creation
- *              This is used to generate the group name.
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is called by the main() function.
- *-------------------------------------------------------------------------
- */
-
-static bool
-create_group(state_t *s, unsigned int which)
-{
-
-    char       name[sizeof("/group-9999999999")];
-    hid_t      g = H5I_INVALID_HID;
-    H5G_info_t group_info;
-
-    if (which >= s->nsteps) {
-        printf("Number of created groups is out of bounds\n");
-        TEST_ERROR;
-    }
-
-    esnprintf(name, sizeof(name), "/group-%u", which);
-    if ((g = H5Gcreate2(s->file, name, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) {
-        printf("H5Gcreate2 failed\n");
-        TEST_ERROR;
-    }
-
-    if (H5Gget_info(g, &group_info) < 0) {
-        printf("H5Gget_info failed\n");
-        TEST_ERROR;
-    }
-
-    if (s->old_style_grp) {
-        if (group_info.storage_type != H5G_STORAGE_TYPE_SYMBOL_TABLE) {
-            printf("Old-styled group test: but the group is not in old-style. \n");
-            TEST_ERROR;
-        }
-        dbgf(2, "Writer: group is created with the old-style.\n");
-    }
-    else {
-        if (group_info.storage_type == H5G_STORAGE_TYPE_SYMBOL_TABLE) {
-            printf("The created group should NOT be in old-style . \n");
-            TEST_ERROR;
-        }
-        dbgf(2, "Writer: group is created with the new-style.\n");
-    }
-
-    if (H5Gclose(g) < 0) {
-        printf("H5Gclose failed\n");
-        TEST_ERROR;
-    }
-
-    return true;
-
-error:
-
-    H5E_BEGIN_TRY
-    {
-        H5Gclose(g);
-    }
-    H5E_END_TRY;
-
-    return false;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    delete_one_link
- *
- * Purpose:     Delete a link(either hard/soft) in group operation tests.
- *              according to the group test pattern.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              hid_t obj_id
- *              The HDF5 object ID that the deleted link is attached to.
- *
- *              const char *name
- *              The name of the link to be deleted.
- *
- *              short link_storage
- *              <=0: link storage is ignored.
- *              1: link storage should be compact after link deletion..
- *              >1: link storage should be dense after link deletion.
- *
- *              unsigned int which
- *              The number of iterations for group creation
- *
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is used by delete_groups() and delete_links() functions.
- *-------------------------------------------------------------------------
- */
-
-static bool
-delete_one_link(state_t *s, hid_t obj_id, const char *name, short link_storage, unsigned int which)
-{
-
-    H5G_info_t group_info;
-
-    if (which >= s->nsteps) {
-        printf("Number of created groups is out of bounds\n");
-        TEST_ERROR;
-    }
-
-    if (H5Ldelete(obj_id, name, H5P_DEFAULT) < 0) {
-        printf("H5Ldelete failed\n");
-        TEST_ERROR;
-    }
-
-    if (link_storage > 0) {
-
-        if (s->old_style_grp) {
-            printf("Old style group doesn't support the indexed storage.\n");
-            TEST_ERROR;
-        }
-
-        if (H5Gget_info(obj_id, &group_info) < 0) {
-            printf("H5Gget_info failed\n");
-            TEST_ERROR;
-        }
-
-        if (link_storage == 1) {
-
-            if (group_info.storage_type != H5G_STORAGE_TYPE_COMPACT) {
-                printf("The group link storage should be compact. \n");
-                TEST_ERROR;
-            }
-        }
-        else {
-
-            if (group_info.storage_type != H5G_STORAGE_TYPE_DENSE) {
-                printf("The group link storage should be dense. \n");
-                TEST_ERROR;
-            }
-        }
-    }
-
-    return true;
-
-error:
-    return false;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    delete_group
- *
- * Purpose:     Delete a group and carry out group operations(add,delete etc.)
- *              according to the group operation test pattern.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              unsigned int which
- *              The number of iterations for group creation
- *              This is used to generate the group name
- *
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is called by the group_operations() function.
- *-------------------------------------------------------------------------
- */
-
-static bool
-delete_group(state_t *s, unsigned int which)
-{
-
-    char name[sizeof("/group-9999999999")];
-    bool ret_value = create_group(s, which);
-    if (ret_value == true) {
-        esnprintf(name, sizeof(name), "/group-%u", which);
-        ret_value = delete_one_link(s, s->file, name, 0, which);
-    }
-
-    return ret_value;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    move_one_group
- *
- * Purpose:     A helper function used by the move_group operation.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              hid_t obj_id
- *              ID of the object this group is attached to
- *
- *              const char *name
- *              The original group name
- *
- *              const char *newname
- *              The new group name
- *
- *              unsigned int which
- *              The number of iterations for group creation
- *
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is called by the move_group() function.
- *-------------------------------------------------------------------------
- */
-
-static bool
-move_one_group(state_t *s, hid_t obj_id, const char *name, const char *newname, unsigned int which)
-{
-
-    if (which >= s->nsteps) {
-        printf("Number of created groups is out of bounds\n");
-        TEST_ERROR;
-    }
-
-    if (H5Lmove(obj_id, name, obj_id, newname, H5P_DEFAULT, H5P_DEFAULT) < 0) {
-        printf("H5Ldelete failed\n");
-        TEST_ERROR;
-    }
-
-    return true;
-
-error:
-    return false;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    move_group
- *
- * Purpose:     Move a group to another group.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              unsigned int which
- *              The number of iterations for group creation
- *              used to generate the group name.
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is called by the group_operations() function.
- *-------------------------------------------------------------------------
- */
-
-static bool
-move_group(state_t *s, unsigned int which)
-{
-
-    char name[sizeof("/group-9999999999")];
-    char new_name[sizeof("/new-group-9999999999")];
-    bool ret_value = create_group(s, which);
-    if (ret_value == true) {
-        esnprintf(name, sizeof(name), "/group-%u", which);
-        esnprintf(new_name, sizeof(new_name), "/new-group-%u", which);
-        ret_value = move_one_group(s, s->file, name, new_name, which);
-    }
-
-    return ret_value;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    insert_one_link
- *
- * Purpose:     A helper function used to attach a link to a group.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              hid_t obj_id
- *              ID of the object this link is attached to
- *
- *              const char *name
- *              The name of the target object used by creating links
- *
- *              const char *newname
- *              The name of the linked objects
- *
- *              bool is_hard
- *              true if inserting a hard link
- *              false if inserting a soft link
- *
- *              short link_storage
- *              <=0: link storage is ignored.
- *              1: link storage should be compact.
- *              >1: link storage should be dense.
-
- *              unsigned int which
- *              The number of iterations for group creation
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is called by the insert_links and link storage transit functions.
- *              For link storage, we test at both the writer and the reader.
- *-------------------------------------------------------------------------
-*/
-
-static bool
-insert_one_link(state_t *s, hid_t obj_id, const char *name, const char *newname, bool is_hard,
-                short link_storage, unsigned int which)
-{
-
-    H5G_info_t group_info;
-
-    if (which >= s->nsteps) {
-        printf("Number of created groups is out of bounds\n");
-        TEST_ERROR;
-    }
-
-    /* For storage transit and insert_links cases, we
-     * create links in different style, just add a little
-     * variation of the tests.*/
-    if (is_hard) {
-        if (link_storage > 0) {
-            if (H5Lcreate_hard(s->file, name, obj_id, newname, H5P_DEFAULT, H5P_DEFAULT) < 0) {
-                printf("H5Lcreate_hard failed\n");
-                TEST_ERROR;
-            }
-        }
-        else {
-            if (H5Lcreate_hard(obj_id, name, obj_id, newname, H5P_DEFAULT, H5P_DEFAULT) < 0) {
-                printf("H5Lcreate_hard failed\n");
-                TEST_ERROR;
-            }
-        }
-    }
-    else {
-        if (link_storage > 0) {
-            if (H5Lcreate_soft("/", obj_id, newname, H5P_DEFAULT, H5P_DEFAULT) < 0) {
-                printf("H5Lcreate_soft failed\n");
-                TEST_ERROR;
-            }
-        }
-        else {
-            if (H5Lcreate_soft(name, obj_id, newname, H5P_DEFAULT, H5P_DEFAULT) < 0) {
-                printf("H5Lcreate_soft failed.\n");
-                TEST_ERROR;
-            }
-        }
-    }
-
-    if (link_storage > 0) {
-
-        if (s->old_style_grp) {
-            printf("Old style group doesn't support dense or compact storage.\n");
-            TEST_ERROR;
-        }
-
-        if (H5Gget_info(obj_id, &group_info) < 0) {
-            printf("H5Gget_info failed\n");
-            TEST_ERROR;
-        }
-
-        if (link_storage == 1) {
-            if (group_info.storage_type != H5G_STORAGE_TYPE_COMPACT) {
-                printf("The group link storage should be compact. \n");
-                TEST_ERROR;
-            }
-        }
-        else {
-            if (group_info.storage_type != H5G_STORAGE_TYPE_DENSE) {
-                printf("The group link storage should be dense. \n");
-                TEST_ERROR;
-            }
-        }
-    }
-
-    return true;
-
-error:
-    return false;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    insert_links
- *
- * Purpose:     create links with a group.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              unsigned int which
- *              The number of iterations
- *              used to generate the group name.
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is called by the group_operations() function.
- *-------------------------------------------------------------------------
- */
-
-static bool
-insert_links(state_t *s, unsigned int which)
-{
-
-    char name[sizeof("/group-9999999999")];
-    char hd_name[sizeof("/hd-group-9999999999")];
-    char st_name[sizeof("/st-group-9999999999")];
-
-    bool ret_value = create_group(s, which);
-    if (ret_value == true) {
-        esnprintf(name, sizeof(name), "/group-%u", which);
-        esnprintf(hd_name, sizeof(hd_name), "/hd-group-%u", which);
-        esnprintf(st_name, sizeof(st_name), "/st-group-%u", which);
-        ret_value = insert_one_link(s, s->file, name, hd_name, true, 0, which);
-        if (ret_value == true)
-            ret_value = insert_one_link(s, s->file, name, st_name, false, 0, which);
-    }
-
-    return ret_value;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    delete_links
- *
- * Purpose:     create links with a group and then delete them successfully.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              unsigned int which
- *              The number of iterations
- *              used to generate the group name.
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is called by the group_operations() function.
- *-------------------------------------------------------------------------
- */
-
-static bool
-delete_links(state_t *s, unsigned int which)
-{
-
-    char name[sizeof("/group-9999999999")];
-    char hd_name[sizeof("/hd-group-9999999999")];
-    char st_name[sizeof("/st-group-9999999999")];
-
-    bool ret_value = insert_links(s, which);
-    if (ret_value == true) {
-        esnprintf(name, sizeof(name), "/group-%u", which);
-        esnprintf(hd_name, sizeof(hd_name), "/hd-group-%u", which);
-        esnprintf(st_name, sizeof(st_name), "/st-group-%u", which);
-        ret_value = delete_one_link(s, s->file, hd_name, 0, which);
-        if (ret_value == true)
-            ret_value = delete_one_link(s, s->file, st_name, 0, which);
-    }
-
-    return ret_value;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    transit_storage_compact_to_dense
- *
- * Purpose:     Add links so that the link storage transits from
- *              compact to dense.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              unsigned int which
- *              The number of iterations used to generate the group name.
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is called by the group_operations() function.
- *-------------------------------------------------------------------------
- */
-
-static bool
-transit_storage_compact_to_dense(state_t *s, unsigned int which)
-{
-
-    char name[sizeof("/group-9999999999")];
-    char hd_name[sizeof("/hd-group-9999999999")];
-    char st_name[sizeof("/st-group-9999999999")];
-
-    hid_t g = create_group_id(s, which, false);
-    if (g < 0) {
-        printf("create_group_id failed\n");
-        TEST_ERROR;
-    }
-
-    /* First insert a hard link, compact storage. */
-    esnprintf(name, sizeof(name), "/group-%u", which);
-    esnprintf(hd_name, sizeof(hd_name), "hd-group-%u", which);
-    if (insert_one_link(s, g, name, hd_name, true, 1, which) == false) {
-        printf("insert_one_link for compact storage failed\n");
-        TEST_ERROR;
-    }
-
-    /* Then insert a soft link, the storage becomes dense. */
-    esnprintf(st_name, sizeof(st_name), "st-group-%u", which);
-    if (insert_one_link(s, g, name, st_name, false, 2, which) == false) {
-        printf("insert_one_link for dense storage failed\n");
-        TEST_ERROR;
-    }
-
-    if (close_group_id(g) == false) {
-        printf("insert_one_link for dense storage failed\n");
-        TEST_ERROR;
-    }
-
-    return true;
-
-error:
-    H5E_BEGIN_TRY
-    {
-        H5Gclose(g);
-    }
-    H5E_END_TRY;
-
-    return false;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    transit_storage_dense_to_compact
- *
- * Purpose:     Add or delete links so that the link storage transits from
- *              compact to dense then to compact.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              unsigned int which
- *              The number of iterations used to generate the group name.
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is called by the group_operations() function.
- *-------------------------------------------------------------------------
- */
-
-static bool
-transit_storage_dense_to_compact(state_t *s, unsigned int which)
-{
-
-    char name[sizeof("/group-9999999999")];
-    char hd_name[sizeof("/hd-group-9999999999")];
-    char st_name[sizeof("st-group-9999999999")];
-    char st2_name[sizeof("st2-group-9999999999")];
-
-    hid_t g = create_group_id(s, which, true);
-    if (g < 0) {
-        printf("create_group_id failed\n");
-        TEST_ERROR;
-    }
-
-    /* Insert a link, storage is compact. */
-    esnprintf(name, sizeof(name), "/group-%u", which);
-    esnprintf(hd_name, sizeof(hd_name), "hd-group-%u", which);
-    if (insert_one_link(s, g, name, hd_name, true, 1, which) == false) {
-        printf("insert_one_link for compact storage failed\n");
-        TEST_ERROR;
-    }
-
-    /* Insert a link, storage is still compact. */
-    esnprintf(st_name, sizeof(st_name), "st-group-%u", which);
-    if (insert_one_link(s, g, name, st_name, false, 1, which) == false) {
-        printf("insert_one_link for compact storage failed\n");
-        TEST_ERROR;
-    }
-
-    /* Insert a link, storage becomes dense. */
-    esnprintf(st2_name, sizeof(st2_name), "st2-group-%u", which);
-    if (insert_one_link(s, g, name, st2_name, false, 2, which) == false) {
-        printf("insert_one_link for dense storage failed\n");
-        TEST_ERROR;
-    }
-
-    /* Delete a link, storage is still dense */
-    if (delete_one_link(s, g, st_name, 2, which) == false) {
-        printf("delete_one_link for dense storage failed\n");
-        TEST_ERROR;
-    }
-
-    /* Delete another link, storage becomes compact */
-    if (delete_one_link(s, g, st2_name, 1, which) == false) {
-        printf("delete_one_link for compact storage failed\n");
-        TEST_ERROR;
-    }
-
-    if (close_group_id(g) == false) {
-        printf("insert_one_link for dense storage failed\n");
-        TEST_ERROR;
-    }
-
-    return true;
-
-error:
-    H5E_BEGIN_TRY
-    {
-        H5Gclose(g);
-    }
-    H5E_END_TRY;
-
-    return false;
-}
-
-/*-------------------------------------------------------------------------
- * Function:    group_operations
- *
- * Purpose:     Carry out group and attribute operations(add,delete etc.)
- *              according to the group operation and attribute test patterns.
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              unsigned int which
- *              The number of iterations for group creation
- *
- *
- * Return:      Success:    true
- *              Failure:    false
- *
- * Note:        This is called by the main() function. The check of attribute
- *              operations is inside the write_group() function.
- *-------------------------------------------------------------------------
- */
-static bool
-group_operations(state_t *s, unsigned int which)
-{
-
-    bool ret_value    = false;
-    char test_pattern = s->grp_op_pattern;
-
-    switch (test_pattern) {
-        case 'c':
-            ret_value = create_group(s, which);
-            break;
-        case 'd':
-            ret_value = delete_group(s, which);
-            break;
-        case 'm':
-            ret_value = move_group(s, which);
-            break;
-        case 'i':
-            ret_value = insert_links(s, which);
-            break;
-        case 'D':
-            ret_value = delete_links(s, which);
-            break;
-        case 't':
-            ret_value = transit_storage_compact_to_dense(s, which);
-            break;
-        case 'T':
-            ret_value = transit_storage_dense_to_compact(s, which);
-            break;
-        case ' ':
-        default:
-            ret_value = write_group(s, which);
-            break;
-    }
-    return ret_value;
-}
-
-static unsigned int grp_counter = 0;
-
-/*-------------------------------------------------------------------------
- * Function:    UI_Pow
- *
- * Purpose:     Helper function to obtain the power 'n' of
- *              an unsigned integer 'x'
- *              Similar to pow(x,y) but for an unsigned integer.
- *
- * Parameters:  unsigned int x
- *              unsigned int n
- *
- * Return:      Return an unsigned integer of value of pow(x,n)
- * Note:        If the returned value is > 2^32-1, an overflow
- *              may occur. For our testing purpose, this may never happen.
- *
- *-------------------------------------------------------------------------
- */
-
-static unsigned int
-UI_Pow(unsigned int x, unsigned int n)
-{
-    unsigned int i; /* Variable used in loop grp_counter */
-    unsigned int number = 1;
-
-    for (i = 0; i < n; ++i)
-        number *= x;
-
-    return (number);
-}
-
-/*-------------------------------------------------------------------------
- * Function:    obtain_tree_level_elems
- *
- * Purpose:     Helper function to obtain the maximum number of elements
- *              at one level.
- *
- * Parameters:  unsigned int total_ele
- *              The total number of elements of a tree(excluding the root)
- *
- *              unsigned int level
- *              The number of nested levels
- *              (If every element of the tree is under the root,
- *                  the level is 0.)
- *
- * Return:      Return the maximum number of elements at one level
- *
- * Example:     If the total number of elements is 6 and level is 1,
- *                 the maximum number of elements is 2.The tree is
- *                 a perfectly balanced tree.
- *              Such as:
- *                   0
- *                1     2
- *              3  4  5   6
- *
- *              If the total number of elements is 5 and level is 1,
- *                 the maximum number of elements is still 2. The
- *                 tree is not balanced, there is no element on the
- *                 right-most leaf but the level is still 1.
- *              Such as:
- *                   0
- *                1     2
- *              3  4  5
- *
- *-------------------------------------------------------------------------
- */
-
-static unsigned int
-obtain_tree_level_elems(unsigned int total_ele, unsigned int level)
-{
-
-    assert(level <= total_ele);
-    /* if every element is under the root, just return the total number of elements. */
-    if (level == 0)
-        return total_ele;
-    else {
-        unsigned int test_elems_level = 0;
-        unsigned     total            = 0;
-        unsigned int i                = 1;
-        /* Obtain the maximum number of elements for a level with the brutal force way. */
-        while (total < total_ele) {
-            test_elems_level++;
-            total = 0;
-            for (i = 1; i <= level + 1; i++)
-                total += UI_Pow(test_elems_level, i);
-        }
-        if (total == total_ele)
-            dbgf(2, "Perfectly match: Number of elements per level is %u\n", test_elems_level);
-        return test_elems_level;
-    }
-}
-
-/*-------------------------------------------------------------------------
- * Function:    gen_tree_struct
- *
- * Purpose:     Generate the nested groups
- *
- * Parameters:  state_t *s
- *              The struct that stores information of HDF5 file
- *              and some VFD SWMR configuration parameters
- *
- *              unsigned int level
- *              The number of nested levels +1
- *              (Note: If every element of the tree is under the root,
- *                     the level is 1 in this function.)
- *              unsigned num_elems_per_level
- *              The maximum number of element in a level
- *              hid_t group_id
- *              The ID of the parent group
- *
- * Return:      Success: true
- *              Failure: false
- */
-static bool
-gen_tree_struct(state_t *s, unsigned int level, unsigned ne_per_level, hid_t pgrp_id)
-{
-
-    char            name[sizeof("group-9999999999")];
-    unsigned int    i;
-    hid_t           grp_id;
-    bool            result = true;
-    H5G_info_t      group_info;
-    struct timespec start_time, end_time;
-    double          temp_time;
-
-    if (level > 0 && grp_counter < s->nsteps) {
-
-        for (i = 0; i < ne_per_level; i++) {
-
-            /* For each i a group is created.
-               Use grp_counter to generate the group name.
-            printf("id: %u,level: %u, index: %u\n",id,level,i);
-            */
-            esnprintf(name, sizeof(name), "group-%u", grp_counter);
-            if (grp_counter == s->nsteps)
-                break;
-
-            dbgf(2, "writer in nested group: step %d\n", grp_counter);
-            if (s->gperf) {
-
-                if (HDclock_gettime(CLOCK_MONOTONIC, &start_time) == -1) {
-                    fprintf(stderr, "HDclock_gettime failed");
-                    TEST_ERROR;
-                }
-            }
-
-            if ((grp_id = H5Gcreate2(pgrp_id, name, H5P_DEFAULT, H5P_DEFAULT, H5P_DEFAULT)) < 0) {
-                printf("H5Gcreate2 failed\n");
-                TEST_ERROR;
-            }
-
-            if (s->gperf) {
-
-                if (HDclock_gettime(CLOCK_MONOTONIC, &end_time) == -1) {
-
-                    fprintf(stderr, "HDclock_gettime failed");
-
-                    TEST_ERROR;
-                }
-
-                temp_time = TIME_PASSED(start_time, end_time);
-                if (temp_time < s->min_gc_time)
-                    s->min_gc_time = temp_time;
-                if (temp_time > s->max_gc_time)
-                    s->max_gc_time = temp_time;
-                s->total_gc_time += temp_time;
-            }
-
-            /* Just check the first group information. */
-            if (grp_counter == 0) {
-                if (H5Gget_info(grp_id, &group_info) < 0) {
-                    printf("H5Gget_info failed\n");
-                    TEST_ERROR;
-                }
-
-                if (s->old_style_grp) {
-                    if (group_info.storage_type != H5G_STORAGE_TYPE_SYMBOL_TABLE) {
-                        printf("Old-styled group test: but the group is not in old-style. \n");
-                        TEST_ERROR;
-                    }
-                    dbgf(2, "Writer: group is created with the old-style.\n");
-                }
-                else {
-                    if (group_info.storage_type == H5G_STORAGE_TYPE_SYMBOL_TABLE) {
-                        printf("The created group should NOT be in old-style . \n");
-                        TEST_ERROR;
-                    }
-                    dbgf(2, "Writer: group is created with the new-style.\n");
-                }
-            }
-
-            /* Then carry out the attribute operation. */
-            if (s->asteps != 0 && grp_counter % s->asteps == 0)
-                result = add_default_group_attr(s, grp_id, grp_counter);
-
-            if (result == false) {
-                printf("Cannot create group attributes. \n");
-                TEST_ERROR;
-            }
-            grp_counter++;
-
-            /* Generate groups in the next level */
-            result = gen_tree_struct(s, level - 1, ne_per_level, grp_id);
-            if (result == false) {
-                printf("Cannot create nested groups. \n");
-                TEST_ERROR;
-            }
-
-            /*  close the group ID. No problem. */
-            if (H5Gclose(grp_id) < 0) {
-                printf("H5Gclose failed. \n");
-                TEST_ERROR;
-            }
-        }
-    }
-
-    return true;
-
-error:
-
-    H5E_BEGIN_TRY
-    {
-        H5Gclose(grp_id);
-    }
-    H5E_END_TRY;
-
-    return false;
-}
-
-int
-main(int argc, char **argv)
-{
-    hid_t                 fapl = H5I_INVALID_HID, fcpl = H5I_INVALID_HID;
-    unsigned              step;
-    bool                  writer = false;
-    state_t               s;
-    const char *          personality;
-    H5F_vfd_swmr_config_t config;
-    bool                  wg_ret = false;
-    struct timespec       start_time, end_time;
-    unsigned int          num_elems_per_level;
-
-    if (!state_init(&s, argc, argv)) {
-        printf("state_init failed\n");
-        TEST_ERROR;
-    }
-
-    personality = HDstrstr(s.progname, "vfd_swmr_log_");
-
-    if (personality != NULL && HDstrcmp(personality, "vfd_swmr_log_writer") == 0)
-        writer = true;
-    else if (personality != NULL && HDstrcmp(personality, "vfd_swmr_log_reader") == 0)
-        writer = false;
-    else {
-        printf("unknown personality, expected vfd_swmr_log_{reader,writer}\n");
-        TEST_ERROR;
-    }
-
-    if (writer == false) {
-        printf("Reader is skipped for the performance tests.\n");
-        return EXIT_SUCCESS;
-    }
-
-    /* config, tick_len, max_lag, writer, flush_raw_data, md_pages_reserved, md_file_path */
-    init_vfd_swmr_config(&config, s.tick_len, s.max_lag, writer, FALSE, 128, "./group-shadow");
-    /* Create the log file log-test under the current directory. */
-    init_vfd_swmr_log(&config, "./log-test");
-
-    /* If old-style option is chosen, use the earliest file format(H5F_LIBVER_EARLIEST)
-     * as the second parameter of H5Pset_libver_bound() that is called by
-     * vfd_swmr_create_fapl. Otherwise, the latest file format(H5F_LIBVER_LATEST)
-     * should be used as the second parameter of H5Pset_libver_bound().
-     * Also pass the use_vfd_swmr, only_meta_page, page buffer size, config to vfd_swmr_create_fapl().*/
-    if ((fapl = vfd_swmr_create_fapl(!s.old_style_grp, s.use_vfd_swmr, true, s.pbs, &config)) < 0) {
-        printf("vfd_swmr_create_fapl failed\n");
-        TEST_ERROR;
-    }
-
-    /* Set fs_strategy (file space strategy) and fs_page_size (file space page size) */
-    if ((fcpl = vfd_swmr_create_fcpl(H5F_FSPACE_STRATEGY_PAGE, s.ps)) < 0) {
-        HDprintf("vfd_swmr_create_fcpl() failed");
-        TEST_ERROR;
-    }
-
-    if (s.nglevels > 0) {
-        if (s.grp_op_pattern != ' ' || s.at_pattern != ' ') {
-            printf("For nested group creation test, only the default option is supported.\n");
-            printf("Please re-run the tests with the appopriate option.\n");
-            TEST_ERROR;
-        }
-    }
-
-    if (s.gperf) {
-
-        if (HDclock_gettime(CLOCK_MONOTONIC, &start_time) == -1) {
-            fprintf(stderr, "HDclock_gettime failed");
-            TEST_ERROR;
-        }
-    }
-
-    s.file = H5Fcreate(s.filename, H5F_ACC_TRUNC, fcpl, fapl);
-
-    if (s.gperf) {
-
-        if (HDclock_gettime(CLOCK_MONOTONIC, &end_time) == -1) {
-            fprintf(stderr, "HDclock_gettime failed");
-            TEST_ERROR;
-        }
-
-        s.fo_total_time = TIME_PASSED(start_time, end_time);
-    }
-
-    if (s.file < 0) {
-        printf("H5Fcreate failed\n");
-        TEST_ERROR;
-    }
-
-    /* If generating nested groups, calculate the maximum number of
-          elements per level.  */
-    if (s.nglevels > 0)
-        num_elems_per_level = obtain_tree_level_elems(s.nsteps, s.nglevels);
-
-    if (s.gperf) {
-
-        if (HDclock_gettime(CLOCK_MONOTONIC, &start_time) == -1) {
-            fprintf(stderr, "HDclock_gettime failed");
-            TEST_ERROR;
-        }
-    }
-
-    /* If generating nested groups */
-    if (s.nglevels > 0) {
-
-        /* for the recursive call, the groups under the root is treated as one level */
-        wg_ret = gen_tree_struct(&s, s.nglevels + 1, num_elems_per_level, s.file);
-        if (wg_ret == false) {
-            printf("write nested group failed at group counter  %u\n", grp_counter);
-            TEST_ERROR;
-        }
-    }
-    else {
-        for (step = 0; step < s.nsteps; step++) {
-
-            dbgf(2, "writer: step %d\n", step);
-            wg_ret = group_operations(&s, step);
-            if (wg_ret == false) {
-                printf("write_group failed at step %d\n", step);
-                TEST_ERROR;
-            }
-        }
-    }
-
-    if (s.gperf) {
-
-        if (HDclock_gettime(CLOCK_MONOTONIC, &end_time) == -1) {
-
-            fprintf(stderr, "HDclock_gettime failed");
-            TEST_ERROR;
-        }
-
-        s.total_time   = TIME_PASSED(start_time, end_time);
-        s.mean_time    = s.total_time / s.nsteps;
-        s.mean_gc_time = s.total_gc_time / s.nsteps;
-    }
-
-    if (H5Pclose(fapl) < 0) {
-        printf("H5Pclose failed\n");
-        TEST_ERROR;
-    }
-
-    if (H5Pclose(fcpl) < 0) {
-        printf("H5Pclose failed\n");
-        TEST_ERROR;
-    }
-
-    if (H5Sclose(s.one_by_one_sid) < 0) {
-        printf("H5Sclose failed\n");
-        TEST_ERROR;
-    }
-
-    if (s.gperf) {
-
-        if (HDclock_gettime(CLOCK_MONOTONIC, &start_time) == -1) {
-
-            fprintf(stderr, "HDclock_gettime failed");
-
-            TEST_ERROR;
-        }
-    }
-
-    if (H5Fclose(s.file) < 0) {
-        printf("H5Fclose failed\n");
-        TEST_ERROR;
-    }
-
-    if (s.gperf) {
-
-        if (HDclock_gettime(CLOCK_MONOTONIC, &end_time) == -1) {
-
-            fprintf(stderr, "HDclock_gettime failed");
-
-            TEST_ERROR;
-        }
-
-        s.fc_total_time = TIME_PASSED(start_time, end_time);
-    }
-
-    /* Performance statistics summary */
-    if (s.gperf) {
-
-        if (verbosity != 0) {
-
-            fprintf(stdout, "\nPerformance Test Configuration: ");
-            if (s.use_vfd_swmr)
-                fprintf(stdout, " Using VFD SWMR \n");
-            else
-                fprintf(stdout, " Not using VFD SWMR \n");
-
-            if (s.old_style_grp)
-                fprintf(stdout, " Groups: Created via the earlist file format(old-style) \n");
-            else
-                fprintf(stdout, " Groups: Created via the latest file format(new-style) \n");
-
-            fprintf(stdout, "\n");
-
-            fprintf(stdout, "The length of a tick              = %u\n", s.tick_len);
-            fprintf(stdout, "The maximum expected lag(in ticks)= %u\n", s.max_lag);
-            fprintf(stdout, "The page size(in bytes)           = %u\n", s.ps);
-            fprintf(stdout, "The page buffer size(in bytes)    = %u\n", s.pbs);
-            fprintf(stdout, "\n");
-            fprintf(stdout, "Number of groups                  = %u\n", s.nsteps);
-            fprintf(stdout, "Group Nested levels               = %u\n", s.nglevels);
-            fprintf(stdout, "Number of attributes              = %u\n", s.num_attrs);
-            fprintf(stdout, "Number of element per attribute   = 1\n");
-            if (s.vlstr_test)
-                fprintf(stdout, "Attribute datatype is variable length string. \n");
-            else if (s.filetype == H5T_STD_U32BE)
-                fprintf(stdout, "Attribute datatype is big-endian unsigned 32-bit integer.\n");
-            else
-                fprintf(stdout, "Attribute datatype is native unsigned 32-bit integer.\n");
-
-            fprintf(stdout, "\n");
-            fprintf(stdout,
-                    "(If the nested level is 0, all the groups are created directly under the root.)\n\n");
-            fprintf(stdout, "group creation maximum time                       =%lf\n", s.max_gc_time);
-            fprintf(stdout, "group creation minimum time                       =%lf\n", s.min_gc_time);
-        }
-
-        fprintf(stdout, "group creation total time                           = %lf\n", s.total_gc_time);
-        fprintf(stdout, "group creation mean time(per group)                 = %lf\n", s.mean_gc_time);
-        fprintf(stdout, "group creation and attributes generation total time = %lf\n", s.total_time);
-        fprintf(stdout, "group creation and attributes generation mean time(per group) = %lf\n", s.mean_time);
-        fprintf(stdout, "H5Fcreate time = %lf\n", s.fo_total_time);
-        fprintf(stdout, "H5Fclose time  = %lf\n", s.fc_total_time);
-    }
-
-    return EXIT_SUCCESS;
-
-error:
-    H5E_BEGIN_TRY
-    {
-        H5Pclose(fapl);
-        H5Pclose(fcpl);
-        H5Sclose(s.one_by_one_sid);
-        H5Fclose(s.file);
-    }
-    H5E_END_TRY;
-
-    return EXIT_FAILURE;
-}
-
-#else /* H5_HAVE_WIN32_API */
-
-int
-main(void)
-{
-    HDfprintf(stderr, "Non-POSIX platform. Skipping.\n");
-    return EXIT_SUCCESS;
-} /* end main() */
-
-#endif /* H5_HAVE_WIN32_API */