[svn-r12806] Description:

    Reduce memory usage for common cases of I/O pipeline filter memory usage.

    Also, clean up some more code...

Tested on:
    Linux/32 2.6 (chicago)
    Linux/64 2.6 (chicago2)

6 files changed, 251 insertions, 156 deletions

diff --git a/src/H5HFtest.c b/src/H5HFtest.c
index 61ad00d..d7f6f5e 100644
--- a/src/H5HFtest.c
+++ b/src/H5HFtest.c
@@ -205,7 +205,7 @@ HDfprintf(stderr, "%s: cparam2->pline.filter[%Zu].name = %s\n", "H5HF_cmp_cparam
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-} /* H5HF_get_cparam_test() */
+} /* H5HF_cmp_cparam_test() */
 
 
 /*-------------------------------------------------------------------------
diff --git a/src/H5Opline.c b/src/H5Opline.c
index 86c8dd7..fefaa78 100644
--- a/src/H5Opline.c
+++ b/src/H5Opline.c
@@ -152,9 +152,22 @@ H5O_pline_decode(H5F_t UNUSED *f, hid_t UNUSED dxpl_id, const uint8_t *p)
 
         /* Filter name, if there is one */
 	if(name_length) {
-	    filter->name = H5MM_malloc(name_length);
-	    HDmemcpy(filter->name, p, name_length);
-	    HDassert(filter->name[name_length - 1] == '\0');
+            size_t actual_name_length;          /* Actual length of name */
+
+            /* Determine actual name length (without padding, but with null terminator) */
+	    actual_name_length = HDstrlen((const char *)p) + 1;
+	    HDassert(actual_name_length <= name_length);
+
+            /* Allocate space for the filter name, or use the internal buffer */
+            if(actual_name_length > H5Z_COMMON_NAME_LEN) {
+                filter->name = H5MM_malloc(actual_name_length);
+                if(NULL == filter->name)
+                    HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed for filter name")
+            } /* end if */
+            else
+                filter->name = filter->_name;
+
+	    HDstrcpy(filter->name, (const char *)p);
 	    p += name_length;
 	} /* end if */
 
@@ -162,12 +175,18 @@ H5O_pline_decode(H5F_t UNUSED *f, hid_t UNUSED dxpl_id, const uint8_t *p)
 	if(filter->cd_nelmts) {
             size_t	j;              /* Local index variable */
 
+            /* Allocate space for the client data elements, or use the internal buffer */
+            if(filter->cd_nelmts > H5Z_COMMON_CD_VALUES) {
+                filter->cd_values = H5MM_malloc(filter->cd_nelmts * sizeof(unsigned));
+                if(NULL == filter->cd_values)
+                    HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed for client data")
+            } /* end if */
+            else
+                filter->cd_values = filter->_cd_values;
+
 	    /*
 	     * Read the client data values and the padding
 	     */
-	    filter->cd_values = H5MM_malloc(filter->cd_nelmts * sizeof(unsigned));
-	    if(NULL == filter->cd_values)
-		HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed for client data")
 	    for(j = 0; j < filter->cd_nelmts; j++)
 		UINT32DECODE(p, filter->cd_values[j]);
             if(version == H5O_PLINE_VERSION_1)
@@ -181,14 +200,8 @@ H5O_pline_decode(H5F_t UNUSED *f, hid_t UNUSED dxpl_id, const uint8_t *p)
 
 done:
     if(NULL == ret_value && pline) {
-        if(pline->filter) {
-            for(i = 0; i < pline->nused; i++) {
-                H5MM_xfree(pline->filter[i].name);
-                H5MM_xfree(pline->filter[i].cd_values);
-            } /* end for */
-            H5MM_xfree(pline->filter);
-        } /* end if */
-        H5FL_FREE(H5O_pline_t,pline);
+        H5O_pline_reset(pline);
+        H5O_pline_free(pline);
     } /* end if */
 
     FUNC_LEAVE_NOAPI(ret_value)
@@ -346,16 +359,36 @@ H5O_pline_copy(const void *_src, void *_dst/*out*/, unsigned UNUSED update_flags
             dst->filter[i] = src->filter[i];
 
             /* Filter name */
-            if(src->filter[i].name)
-                if(NULL == (dst->filter[i].name = H5MM_xstrdup(src->filter[i].name)))
-                    HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
+            if(src->filter[i].name) {
+                size_t namelen;         /* Length of source filter name, including null terminator  */
+
+                namelen = HDstrlen(src->filter[i].name) + 1;
+
+                /* Allocate space for the filter name, or use the internal buffer */
+                if(namelen > H5Z_COMMON_NAME_LEN) {
+                    dst->filter[i].name = H5MM_malloc(namelen);
+                    if(NULL == dst->filter[i].name)
+                        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed for filter name")
+
+                    /* Copy name */
+                    HDstrcpy(dst->filter[i].name, src->filter[i].name);
+                } /* end if */
+                else
+                    dst->filter[i].name = dst->filter[i]._name;
+            } /* end if */
 
             /* Filter parameters */
             if(src->filter[i].cd_nelmts > 0) {
-                if(NULL == (dst->filter[i].cd_values = H5MM_malloc(src->filter[i].cd_nelmts* sizeof(unsigned))))
-                    HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
-                HDmemcpy(dst->filter[i].cd_values, src->filter[i].cd_values,
-                          src->filter[i].cd_nelmts * sizeof(unsigned));
+                /* Allocate space for the client data elements, or use the internal buffer */
+                if(src->filter[i].cd_nelmts > H5Z_COMMON_CD_VALUES) {
+                    if(NULL == (dst->filter[i].cd_values = H5MM_malloc(src->filter[i].cd_nelmts* sizeof(unsigned))))
+                        HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
+
+                    HDmemcpy(dst->filter[i].cd_values, src->filter[i].cd_values,
+                            src->filter[i].cd_nelmts * sizeof(unsigned));
+                } /* end if */
+                else
+                    dst->filter[i].cd_values = dst->filter[i]._cd_values;
             } /* end if */
         } /* end for */
     } /* end if */
@@ -367,15 +400,9 @@ H5O_pline_copy(const void *_src, void *_dst/*out*/, unsigned UNUSED update_flags
 
 done:
     if(!ret_value && dst) {
-	if(dst->filter) {
-	    for(i = 0; i < dst->nused; i++) {
-		H5MM_xfree(dst->filter[i].name);
-		H5MM_xfree(dst->filter[i].cd_values);
-	    } /* end for */
-	    H5MM_xfree(dst->filter);
-	} /* end if */
+        H5O_pline_reset(dst);
 	if(!_dst)
-            H5FL_FREE(H5O_pline_t,dst);
+            H5O_pline_free(dst);
     } /* end if */
 
     FUNC_LEAVE_NOAPI(ret_value)
@@ -475,8 +502,14 @@ H5O_pline_reset(void *mesg)
 
     /* Free information for each filter */
     for(i = 0; i < pline->nused; i++) {
-        H5MM_xfree(pline->filter[i].name);
-        H5MM_xfree(pline->filter[i].cd_values);
+        if(pline->filter[i].name && pline->filter[i].name != pline->filter[i]._name)
+            HDassert((HDstrlen(pline->filter[i].name) + 1) > H5Z_COMMON_NAME_LEN);
+        if(pline->filter[i].name != pline->filter[i]._name)
+            pline->filter[i].name = H5MM_xfree(pline->filter[i].name);
+        if(pline->filter[i].cd_values && pline->filter[i].cd_values != pline->filter[i]._cd_values)
+            HDassert(pline->filter[i].cd_nelmts > H5Z_COMMON_CD_VALUES);
+        if(pline->filter[i].cd_values != pline->filter[i]._cd_values)
+            pline->filter[i].cd_values = H5MM_xfree(pline->filter[i].cd_values);
     } /* end for */
 
     /* Free filter array */
@@ -500,8 +533,6 @@ H5O_pline_reset(void *mesg)
  * Programmer:	Quincey Koziol
  *              Saturday, March 11, 2000
  *
- * Modifications:
- *
  *-------------------------------------------------------------------------
  */
 static herr_t
diff --git a/src/H5Z.c b/src/H5Z.c
index f11756b..b83377d 100644
--- a/src/H5Z.c
+++ b/src/H5Z.c
@@ -698,23 +698,22 @@ H5Z_modify(const H5O_pline_t *pline, H5Z_filter_t filter, unsigned flags,
 	   size_t cd_nelmts, const unsigned int cd_values[/*cd_nelmts*/])
 {
     size_t	idx;                    /* Index of filter in pipeline */
-    size_t	i;                      /* Local index variable */
-    herr_t      ret_value=SUCCEED;      /* Return value */
+    herr_t      ret_value = SUCCEED;      /* Return value */
 
     FUNC_ENTER_NOAPI(H5Z_modify, FAIL)
 
-    assert(pline);
-    assert(filter>=0 && filter<=H5Z_FILTER_MAX);
-    assert(0==(flags & ~((unsigned)H5Z_FLAG_DEFMASK)));
-    assert(0==cd_nelmts || cd_values);
+    HDassert(pline);
+    HDassert(filter >= 0 && filter <= H5Z_FILTER_MAX);
+    HDassert(0 == (flags & ~((unsigned)H5Z_FLAG_DEFMASK)));
+    HDassert(0 == cd_nelmts || cd_values);
 
     /* Locate the filter in the pipeline */
-    for(idx=0; idx<pline->nused; idx++)
-        if(pline->filter[idx].id==filter)
+    for(idx = 0; idx < pline->nused; idx++)
+        if(pline->filter[idx].id == filter)
             break;
 
     /* Check if the filter was not already in the pipeline */
-    if(idx>pline->nused)
+    if(idx > pline->nused)
 	HGOTO_ERROR(H5E_PLINE, H5E_NOTFOUND, FAIL, "filter not in pipeline")
 
     /* Change parameters for filter */
@@ -722,15 +721,24 @@ H5Z_modify(const H5O_pline_t *pline, H5Z_filter_t filter, unsigned flags,
     pline->filter[idx].cd_nelmts = cd_nelmts;
 
     /* Free any existing parameters */
-    if(pline->filter[idx].cd_values!=NULL)
+    if(pline->filter[idx].cd_values != NULL && pline->filter[idx].cd_values != pline->filter[idx]._cd_values)
 	H5MM_xfree(pline->filter[idx].cd_values);
 
     /* Set parameters */
-    if (cd_nelmts>0) {
-	pline->filter[idx].cd_values = H5MM_malloc(cd_nelmts*sizeof(unsigned));
-	if (NULL==pline->filter[idx].cd_values)
-	    HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for filter parameters")
-	for (i=0; i<cd_nelmts; i++)
+    if(cd_nelmts > 0) {
+        size_t	i;                      /* Local index variable */
+
+        /* Allocate memory or point at internal buffer */
+        if(cd_nelmts > H5Z_COMMON_CD_VALUES) {
+            pline->filter[idx].cd_values = H5MM_malloc(cd_nelmts * sizeof(unsigned));
+            if(NULL == pline->filter[idx].cd_values)
+                HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for filter parameters")
+        } /* end if */
+        else
+            pline->filter[idx].cd_values = pline->filter[idx]._cd_values;
+
+        /* Copy client data values */
+	for(i = 0; i < cd_nelmts; i++)
 	    pline->filter[idx].cd_values[i] = cd_values[i];
     } /* end if */
     else
@@ -759,33 +767,34 @@ herr_t
 H5Z_append(H5O_pline_t *pline, H5Z_filter_t filter, unsigned flags,
 	   size_t cd_nelmts, const unsigned int cd_values[/*cd_nelmts*/])
 {
-    size_t	idx, i;
-    herr_t      ret_value=SUCCEED;       /* Return value */
+    size_t	idx;
+    herr_t      ret_value = SUCCEED;       /* Return value */
 
     FUNC_ENTER_NOAPI(H5Z_append, FAIL)
 
-    assert(pline);
-    assert(filter>=0 && filter<=H5Z_FILTER_MAX);
-    assert(0==(flags & ~((unsigned)H5Z_FLAG_DEFMASK)));
-    assert(0==cd_nelmts || cd_values);
+    HDassert(pline);
+    HDassert(filter >= 0 && filter <= H5Z_FILTER_MAX);
+    HDassert(0 == (flags & ~((unsigned)H5Z_FLAG_DEFMASK)));
+    HDassert(0 == cd_nelmts || cd_values);
 
     /*
      * Check filter limit.  We do it here for early warnings although we may
      * decide to relax this restriction in the future.
      */
-    if (pline->nused>=H5Z_MAX_NFILTERS)
+    if(pline->nused >= H5Z_MAX_NFILTERS)
 	HGOTO_ERROR(H5E_PLINE, H5E_CANTINIT, FAIL, "too many filters in pipeline")
 
     /* Allocate additional space in the pipeline if it's full */
-    if (pline->nused>=pline->nalloc) {
+    if(pline->nused >= pline->nalloc) {
 	H5O_pline_t x;
-	x.nalloc = MAX(H5Z_MAX_NFILTERS, 2*pline->nalloc);
+
+	x.nalloc = MAX(H5Z_MAX_NFILTERS, 2 * pline->nalloc);
 	x.filter = H5MM_realloc(pline->filter, x.nalloc*sizeof(x.filter[0]));
-	if (NULL==x.filter)
+	if(NULL == x.filter)
 	    HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for filter pipeline")
 	pline->nalloc = x.nalloc;
 	pline->filter = x.filter;
-    }
+    } /* end if */
 
     /* Add the new filter to the pipeline */
     idx = pline->nused;
@@ -793,20 +802,30 @@ H5Z_append(H5O_pline_t *pline, H5Z_filter_t filter, unsigned flags,
     pline->filter[idx].flags = flags;
     pline->filter[idx].name = NULL; /*we'll pick it up later*/
     pline->filter[idx].cd_nelmts = cd_nelmts;
-    if (cd_nelmts>0) {
-	pline->filter[idx].cd_values = H5MM_malloc(cd_nelmts*sizeof(unsigned));
-	if (NULL==pline->filter[idx].cd_values)
-	    HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for filter")
-	for (i=0; i<cd_nelmts; i++)
+    if(cd_nelmts > 0) {
+        size_t	i;                      /* Local index variable */
+
+        /* Allocate memory or point at internal buffer */
+        if(cd_nelmts > H5Z_COMMON_CD_VALUES) {
+            pline->filter[idx].cd_values = H5MM_malloc(cd_nelmts * sizeof(unsigned));
+            if(NULL == pline->filter[idx].cd_values)
+                HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for filter")
+        } /* end if */
+        else
+            pline->filter[idx].cd_values = pline->filter[idx]._cd_values;
+
+        /* Copy client data values */
+	for(i = 0; i < cd_nelmts; i++)
 	    pline->filter[idx].cd_values[i] = cd_values[i];
-    } else {
+    } /* end if */
+    else
        pline->filter[idx].cd_values = NULL;
-    }
+
     pline->nused++;
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-}
+} /* end H5Z_append() */
 
 
 /*-------------------------------------------------------------------------
@@ -1129,58 +1148,71 @@ done:
 herr_t
 H5Z_delete(H5O_pline_t *pline, H5Z_filter_t filter)
 {
-    herr_t ret_value=SUCCEED; /* Return value */
+    herr_t ret_value = SUCCEED; /* Return value */
 
     FUNC_ENTER_NOAPI(H5Z_delete, FAIL)
 
     /* Check args */
-    assert(pline);
-    assert(filter>=0 && filter<=H5Z_FILTER_MAX);
+    HDassert(pline);
+    HDassert(filter >= 0 && filter <= H5Z_FILTER_MAX);
 
     /* if the pipeline has no filters, just return */
     if(pline->nused==0)
         HGOTO_DONE(SUCCEED)
 
     /* Delete all filters */
-    if (H5Z_FILTER_ALL==filter) {
-        if(H5O_reset(H5O_PLINE_ID, pline)<0)
+    if(H5Z_FILTER_ALL == filter) {
+        if(H5O_reset(H5O_PLINE_ID, pline) < 0)
             HGOTO_ERROR(H5E_PLINE, H5E_CANTFREE, FAIL, "can't release pipeline info")
     } /* end if */
     /* Delete filter */
     else {
         size_t idx;             /* Index of filter in pipeline */
-        unsigned found=0;       /* Indicate filter was found in pipeline */
+        hbool_t found = FALSE;  /* Indicate filter was found in pipeline */
 
         /* Locate the filter in the pipeline */
-        for(idx=0; idx<pline->nused; idx++)
-            if(pline->filter[idx].id==filter) {
-                found=1;
+        for(idx = 0; idx < pline->nused; idx++)
+            if(pline->filter[idx].id == filter) {
+                found = TRUE;
                 break;
-            }
+            } /* end if */
 
         /* filter was not found in the pipeline */
-        if (!found)
+        if(!found)
             HGOTO_ERROR(H5E_PLINE, H5E_NOTFOUND, FAIL, "filter not in pipeline")
 
         /* Free information for deleted filter */
-        H5MM_xfree(pline->filter[idx].name);
-        H5MM_xfree(pline->filter[idx].cd_values);
+        if(pline->filter[idx].name && pline->filter[idx].name != pline->filter[idx]._name)
+            HDassert((HDstrlen(pline->filter[idx].name) + 1) > H5Z_COMMON_NAME_LEN);
+        if(pline->filter[idx].name != pline->filter[idx]._name)
+            pline->filter[idx].name = H5MM_xfree(pline->filter[idx].name);
+        if(pline->filter[idx].cd_values && pline->filter[idx].cd_values != pline->filter[idx]._cd_values)
+            HDassert(pline->filter[idx].cd_nelmts > H5Z_COMMON_CD_VALUES);
+        if(pline->filter[idx].cd_values != pline->filter[idx]._cd_values)
+            pline->filter[idx].cd_values = H5MM_xfree(pline->filter[idx].cd_values);
 
         /* Remove filter from pipeline array */
-        if((idx+1)<pline->nused)
-            HDmemcpy(&pline->filter[idx], &pline->filter[idx+1],
-                sizeof (H5Z_filter_info_t)*(pline->nused-(idx+1)));
+        if((idx + 1) < pline->nused) {
+            /* Copy filters down & fix up any client data value arrays using internal storage */
+            for(; (idx + 1) < pline->nused; idx++) {
+                pline->filter[idx] = pline->filter[idx + 1];
+                if(pline->filter[idx].name && (HDstrlen(pline->filter[idx].name) + 1) <= H5Z_COMMON_NAME_LEN)
+                    pline->filter[idx].name = pline->filter[idx]._name;
+                if(pline->filter[idx].cd_nelmts <= H5Z_COMMON_CD_VALUES)
+                    pline->filter[idx].cd_values = pline->filter[idx]._cd_values;
+            } /* end for */
+        } /* end if */
 
         /* Decrement number of used filters */
         pline->nused--;
 
         /* Reset information for previous last filter in pipeline */
-        HDmemset(&pline->filter[pline->nused], 0, sizeof (H5Z_filter_info_t));
+        HDmemset(&pline->filter[pline->nused], 0, sizeof(H5Z_filter_info_t));
     } /* end else */
 
 done:
     FUNC_LEAVE_NOAPI(ret_value)
-}
+} /* end H5Z_delete() */
 
 /*-------------------------------------------------------------------------
  * Function: H5Zget_filter_info
diff --git a/src/H5Zprivate.h b/src/H5Zprivate.h
index e13876a..822e95d 100644
--- a/src/H5Zprivate.h
+++ b/src/H5Zprivate.h
@@ -25,23 +25,49 @@
 /* Private headers needed by this file */
 #include "H5Tprivate.h"		/* Datatypes				*/
 
+/**************************/
+/* Library Private Macros */
+/**************************/
+
+/* Special parameters for szip compression */
+/* [These are aliases for the similar definitions in szlib.h, which we can't
+ * include directly due to the duplication of various symbols with the zlib.h
+ * header file] */
+#define H5_SZIP_LSB_OPTION_MASK         8
+#define H5_SZIP_MSB_OPTION_MASK         16
+#define H5_SZIP_RAW_OPTION_MASK         128
+
+/* Common # of 'client data values' for filters */
+/* (avoids dynamic memory allocation in most cases) */
+#define H5Z_COMMON_CD_VALUES    4
+
+/* Common size of filter name */
+/* (avoids dynamic memory allocation in most cases) */
+#define H5Z_COMMON_NAME_LEN    12
+
+/****************************/
+/* Library Private Typedefs */
+/****************************/
+
 /* Structure to store information about each filter's parameters */
 typedef struct {
     H5Z_filter_t	id;		/*filter identification number	     */
     unsigned		flags;		/*defn and invocation flags	     */
+    char		_name[H5Z_COMMON_NAME_LEN];	/*internal filter name		     */
     char		*name;		/*optional filter name		     */
     size_t		cd_nelmts;	/*number of elements in cd_values[]  */
+    unsigned		_cd_values[H5Z_COMMON_CD_VALUES];	/*internal client data values		     */
     unsigned		*cd_values;	/*client data values		     */
 } H5Z_filter_info_t;
 
-/* Special parameters for szip compression */
-/* [These are aliases for the similar definitions in szlib.h, which we can't
- * include directly due to the duplication of various symbols with the zlib.h
- * header file] */
-#define H5_SZIP_LSB_OPTION_MASK         8
-#define H5_SZIP_MSB_OPTION_MASK         16
-#define H5_SZIP_RAW_OPTION_MASK         128
+/*****************************/
+/* Library-private Variables */
+/*****************************/
+
 
+/***************************************/
+/* Library-private Function Prototypes */
+/***************************************/
 struct H5O_pline_t; /*forward decl*/
 
 /* Internal API routines */
diff --git a/src/H5Zpublic.h b/src/H5Zpublic.h
index c632c65..9b2fb3e 100644
--- a/src/H5Zpublic.h
+++ b/src/H5Zpublic.h
@@ -42,7 +42,13 @@ typedef int H5Z_filter_t;
 
 /* General macros */
 #define H5Z_FILTER_ALL	 	0	/* Symbol to remove all filters in H5Premove_filter */
-#define H5Z_MAX_NFILTERS        32      /* Maximum number of filters allowed in a pipeline (should probably be allowed to be an unlimited amount) */
+#define H5Z_MAX_NFILTERS        32      /* Maximum number of filters allowed in a pipeline */
+                                        /* (should probably be allowed to be an
+                                         * unlimited amount, but currently each
+                                         * filter uses a bit in a 32-bit field,
+                                         * so the format would have to be
+                                         * changed to accomodate that)
+                                         */
 
 /* Flags for filter definition (stored) */
 #define H5Z_FLAG_DEFMASK	0x00ff	/*definition flag mask		*/
diff --git a/test/dsets.c b/test/dsets.c
index 8508b37..3dae7f0 100644
--- a/test/dsets.c
+++ b/test/dsets.c
@@ -5620,72 +5620,72 @@ error:
 static herr_t
 auxread_fdata(hid_t fid, const char *name)
 {
- hid_t     dset_id=-1;           /* dataset ID */
- hid_t     dcpl_id=-1;           /* dataset creation property list ID */
- hid_t     space_id=-1;          /* space ID */
- hid_t     ftype_id=-1;          /* file data type ID */
- hid_t     mtype_id=-1;          /* memory data type ID */
- size_t    msize;             /* memory size of memory type */
- void      *buf=NULL;         /* data buffer */
- hsize_t   nelmts;            /* number of elements in dataset */
- int       rank;              /* rank of dataset */
- hsize_t   dims[H5S_MAX_RANK];/* dimensions of dataset */
- int       i;
-
- if ((dset_id=H5Dopen(fid,name))<0)
-  goto error;
- if ((space_id=H5Dget_space(dset_id))<0)
-  goto error;
- if ((ftype_id=H5Dget_type (dset_id))<0)
-  goto error;
- if ((dcpl_id=H5Dget_create_plist(dset_id))<0)
-  goto error;
- if ( (rank=H5Sget_simple_extent_ndims(space_id))<0)
-  goto error;
- HDmemset(dims, 0, sizeof dims);
- if ( H5Sget_simple_extent_dims(space_id,dims,NULL)<0)
-  goto error;
- nelmts=1;
- for (i=0; i<rank; i++)
-  nelmts*=dims[i];
- if ((mtype_id=H5Tget_native_type(ftype_id,H5T_DIR_DEFAULT))<0)
-  goto error;
- if ((msize=H5Tget_size(mtype_id))==0)
-  goto error;
-
- if (nelmts)
- {
-  buf=(void *) HDmalloc((unsigned)(nelmts*msize));
-  if ( buf==NULL){
-   printf( "cannot read into memory\n" );
-   goto error;
-  }
-  if (H5Dread(dset_id,mtype_id,H5S_ALL,H5S_ALL,H5P_DEFAULT,buf)<0)
-   goto error;
- }
+    hid_t     dset_id=-1;           /* dataset ID */
+    hid_t     dcpl_id=-1;           /* dataset creation property list ID */
+    hid_t     space_id=-1;          /* space ID */
+    hid_t     ftype_id=-1;          /* file data type ID */
+    hid_t     mtype_id=-1;          /* memory data type ID */
+    size_t    msize;             /* memory size of memory type */
+    void      *buf=NULL;         /* data buffer */
+    hsize_t   nelmts;            /* number of elements in dataset */
+    int       rank;              /* rank of dataset */
+    hsize_t   dims[H5S_MAX_RANK];/* dimensions of dataset */
+    int       i;
 
- if (H5Pclose(dcpl_id)<0)
-  goto error;
- if (H5Sclose(space_id)<0)
-  goto error;
- if (H5Dclose(dset_id)<0)
-  goto error;
- if (buf)
-  free(buf);
+    if ((dset_id=H5Dopen(fid,name))<0)
+        goto error;
+    if ((space_id=H5Dget_space(dset_id))<0)
+        goto error;
+    if ((ftype_id=H5Dget_type (dset_id))<0)
+        goto error;
+    if ((dcpl_id=H5Dget_create_plist(dset_id))<0)
+        goto error;
+    if ( (rank=H5Sget_simple_extent_ndims(space_id))<0)
+        goto error;
+    HDmemset(dims, 0, sizeof dims);
+    if ( H5Sget_simple_extent_dims(space_id,dims,NULL)<0)
+        goto error;
+    nelmts=1;
+    for (i=0; i<rank; i++)
+        nelmts*=dims[i];
+    if ((mtype_id=H5Tget_native_type(ftype_id,H5T_DIR_DEFAULT))<0)
+        goto error;
+    if ((msize=H5Tget_size(mtype_id))==0)
+        goto error;
 
- return 0;
+    if (nelmts)
+    {
+        buf=(void *) HDmalloc((unsigned)(nelmts*msize));
+        if ( buf==NULL){
+            printf( "cannot read into memory\n" );
+            goto error;
+        }
+        if (H5Dread(dset_id,mtype_id,H5S_ALL,H5S_ALL,H5P_DEFAULT,buf)<0)
+            goto error;
+    }
+
+    if (H5Pclose(dcpl_id)<0)
+        goto error;
+    if (H5Sclose(space_id)<0)
+        goto error;
+    if (H5Dclose(dset_id)<0)
+        goto error;
+    if (buf)
+        free(buf);
+
+    return 0;
 
 error:
- H5E_BEGIN_TRY {
-  H5Pclose(dcpl_id);
-  H5Sclose(space_id);
-  H5Dclose(dset_id);
-  H5Tclose(ftype_id);
-  H5Tclose(mtype_id);
-  if (buf)
-   free(buf);
- } H5E_END_TRY;
- return -1;
+    H5E_BEGIN_TRY {
+        H5Pclose(dcpl_id);
+        H5Sclose(space_id);
+        H5Dclose(dset_id);
+        H5Tclose(ftype_id);
+        H5Tclose(mtype_id);
+        if (buf)
+            free(buf);
+    } H5E_END_TRY;
+    return -1;
 }