[svn-r10506] Purpose:

    New feature

Description:
    Add first iteration of "segmented heap" code, which will be used to store
links in groups in a more flexible way than the previous "local heap" mechanism.

Platforms tested:
    FreeBSD 4.11 (sleipnir) w/parallel
    Solaris 2.9 (shanti)

17 files changed, 1314 insertions, 39 deletions

diff --git a/MANIFEST b/MANIFEST
index afae0e8..56bfc7e 100644
--- a/MANIFEST
+++ b/MANIFEST
@@ -934,6 +934,12 @@
 ./src/H5Spublic.h
 ./src/H5Sselect.c
 ./src/H5Stest.c
+./src/H5SH.c
+./src/H5SHcache.c
+./src/H5SHdbg.c
+./src/H5SHpkg.h
+./src/H5SHpublic.h
+./src/H5SHprivate.h
 ./src/H5SL.c
 ./src/H5SLprivate.h
 ./src/H5ST.c
@@ -1033,6 +1039,7 @@
 ./test/srb_append.c
 ./test/srb_read.c
 ./test/srb_write.c
+./test/sheap.c
 ./test/stab.c
 ./test/stream_test.c
 ./test/tarray.c
@@ -1683,8 +1690,8 @@
 ./windows/examples/grouptestdll/grouptestdll.dsp
 ./windows/examples/readtest/readtest.dsp
 ./windows/examples/readtestdll/readtestdll.dsp
-./windows/examples/selectest/selecttest.dsp
-./windows/examples/selectestdll/selecttestdll.dsp
+./windows/examples/selectest/selectest.dsp
+./windows/examples/selectestdll/selectestdll.dsp
 ./windows/examples/writetest/writetest.dsp
 ./windows/examples/writetestdll/writetestdll.dsp
 ./windows/examples/testExamples.bat
diff --git a/src/H5AC.c b/src/H5AC.c
index ac38aa0..1bb0066 100644
--- a/src/H5AC.c
+++ b/src/H5AC.c
@@ -347,7 +347,8 @@ static const char * H5AC_entry_type_names[H5AC_NTYPES] =
     "v2 B-tree headers",
     "v2 B-tree internal nodes",
     "v2 B-tree leaf nodes",
-    "block tracker nodes"
+    "block tracker nodes",
+    "segmented heaps"
 };
 
 herr_t
diff --git a/src/H5ACprivate.h b/src/H5ACprivate.h
index bdfc57b..cb5839a 100644
--- a/src/H5ACprivate.h
+++ b/src/H5ACprivate.h
@@ -48,7 +48,8 @@
 #define H5AC_BT2_INT_ID 6	/*v2 B-tree internal node		     */
 #define H5AC_BT2_LEAF_ID 7	/*v2 B-tree leaf node			     */
 #define H5AC_BLTR_ID	8	/*block tracker				     */
-#define H5AC_NTYPES	9
+#define H5AC_SHEAP_ID	9	/*segmented heap			     */
+#define H5AC_NTYPES	10
 
 /* H5AC_DUMP_STATS_ON_CLOSE should always be FALSE when 
  * H5C_COLLECT_CACHE_STATS is FALSE.  
diff --git a/src/H5Cpkg.h b/src/H5Cpkg.h
index edd67e7..9b1a2a2 100644
--- a/src/H5Cpkg.h
+++ b/src/H5Cpkg.h
@@ -574,7 +574,7 @@
  ****************************************************************************/
 
 #define H5C__H5C_T_MAGIC	0x005CAC0E
-#define H5C__MAX_NUM_TYPE_IDS	9
+#define H5C__MAX_NUM_TYPE_IDS	10
 #define H5C__MAX_EPOCH_MARKERS  10
 
 struct H5C_t
diff --git a/src/H5FDpublic.h b/src/H5FDpublic.h
index 6606b80..444627f 100644
--- a/src/H5FDpublic.h
+++ b/src/H5FDpublic.h
@@ -48,6 +48,14 @@ typedef enum H5FD_mem_t {
  * enough to object headers and probably too minor to deserve their own type. -QAK */
 #define H5FD_MEM_BLKTRK H5FD_MEM_OHDR
 
+/* Map "segmented heap" header blocks to 'ohdr' type file memory, since its
+ * a fair amount of work to add a new kind of file memory, they are similar
+ * enough to object headers and probably too minor to deserve their own type.
+ * Map "segmented heap" blocks to 'lheap' type file memory, since they will be
+ * replacing local heaps. -QAK */
+#define H5FD_MEM_SHEAP_HDR      H5FD_MEM_OHDR
+#define H5FD_MEM_SHEAP_BLOCK    H5FD_MEM_LHEAP
+
 /*
  * A free-list map which maps all types of allocation requests to a single
  * free list.  This is useful for drivers that don't really care about
diff --git a/src/H5SH.c b/src/H5SH.c
new file mode 100644
index 0000000..a72a8c0
--- /dev/null
+++ b/src/H5SH.c
@@ -0,0 +1,326 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * 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 files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic HDF5 document set and   *
+ * is linked from the top-level documents page.  It can also be found at     *
+ * http://hdf.ncsa.uiuc.edu/HDF5/doc/Copyright.html.  If you do not have     *
+ * access to either file, you may request a copy from hdfhelp@ncsa.uiuc.edu. *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*-------------------------------------------------------------------------
+ *
+ * Created:		H5SH.c
+ *			Mar  9 2005
+ *			Quincey Koziol <koziol@ncsa.uiuc.edu>
+ *
+ * Purpose:		Implement "segmented heaps".  These heaps are
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#define H5SH_PACKAGE		/*suppress error about including H5SHpkg  */
+
+/* Private headers */
+#include "H5private.h"		/* Generic Functions			*/
+#include "H5BTprivate.h"	/* Block tracker			*/
+#include "H5Eprivate.h"		/* Error handling		  	*/
+#include "H5MFprivate.h"	/* File memory management		*/
+#include "H5SHpkg.h"		/* Segmented heap			*/
+
+/* Local macros */
+
+/* Local typedefs */
+
+/* Information needed for extending a heap block during an allocation */
+typedef struct {
+    H5F_t *f;                   /* File to search for space within */
+    hid_t dxpl_id;              /* DXPL for allocation operation */
+    haddr_t bt_free_addr;       /* Location of free space B-tree */
+    H5FD_mem_t file_mem_type;   /* Type of file memory being used */
+    hsize_t max_extend_size;    /* Maximum size of a block to consider for extention */
+    hsize_t space_needed;       /* Amount of space to allocate */
+    haddr_t loc;                /* Location of space allocated */
+    haddr_t extend_addr;        /* Extended space address */
+    hsize_t extend_size;        /* Extended space size */
+} H5SH_extend_t;
+
+/* Local prototypes */
+
+/* Package variables */
+
+/* Declare a free list to manage the H5SH_t struct */
+H5FL_DEFINE(H5SH_t);
+
+/* Static variables */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5SH_create
+ *
+ * Purpose:	Creates a new empty segmented heap in the file.
+ *
+ * Return:	Non-negative on success (with address of new segmented heap
+ *              filled in), negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Mar 23 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5SH_create(H5F_t *f, hid_t dxpl_id, haddr_t *addr_p, H5SH_data_type_t heap_type,
+    hsize_t min_size, hsize_t max_extend_size)
+{
+    H5SH_t *sh = NULL;          /* Segmented heap info */
+    herr_t ret_value=SUCCEED;   /* Return value */
+
+    FUNC_ENTER_NOAPI(H5SH_create, FAIL)
+
+    /*
+     * Check arguments.
+     */
+    HDassert(f);
+    HDassert(min_size > 0);
+    HDassert(max_extend_size >= min_size);
+
+    /*
+     * Allocate file and memory data structures.
+     */
+    if (NULL == (sh = H5FL_CALLOC(H5SH_t)))
+	HGOTO_ERROR (H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for segmented heap info")
+
+    /* Assign internal information */
+    sh->cache_info.is_dirty = TRUE;
+    sh->heap_type = heap_type;
+    if(sh->heap_type == H5SH_RAW)
+        sh->file_mem_type = H5FD_MEM_DRAW;
+    else
+        sh->file_mem_type = H5FD_MEM_SHEAP_BLOCK;
+    sh->min_size = min_size;
+    sh->max_extend_size = max_extend_size;
+
+    /* Allocate space for the header on disk */
+    if (HADDR_UNDEF == (*addr_p = H5MF_alloc(f, H5FD_MEM_SHEAP_HDR, dxpl_id, (hsize_t)H5SH_SIZE(f))))
+	HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "file allocation failed for segmented heap info")
+
+    /* Create a block tracker for storing heap block info */
+    if (H5BT_create(f, dxpl_id, &sh->bt_heap_addr/*out*/) < 0)
+	HGOTO_ERROR(H5E_HEAP, H5E_CANTINIT, FAIL, "can't create block tracker for storing heap block info")
+
+    /* Create a block tracker for storing free space info */
+    if (H5BT_create(f, dxpl_id, &sh->bt_free_addr/*out*/) < 0)
+	HGOTO_ERROR(H5E_HEAP, H5E_CANTINIT, FAIL, "can't create block tracker for storing free space info")
+
+    /* Cache the new segmented heap node */
+    if (H5AC_set(f, dxpl_id, H5AC_SGHP, *addr_p, sh, H5AC__NO_FLAGS_SET) < 0)
+	HGOTO_ERROR(H5E_HEAP, H5E_CANTINIT, FAIL, "can't add segmented heap info to cache")
+
+done:
+    if (ret_value<0) {
+	if (sh)
+            (void)H5SH_cache_dest(f, sh);
+    } /* end if */
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5SH_create() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5SH_alloc_extend_cb
+ *
+ * Purpose:	Extend an existing heap block if possible
+ *
+ * Return:	Non-negative on success (setting flag to indicate block
+ *              was extended), negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Mar 25 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static int
+H5SH_alloc_extend_cb(const H5BT_blk_info_t *record, void *_op_data)
+{
+    H5SH_extend_t *ex_info = (H5SH_extend_t *)_op_data;
+    htri_t extendable;          /* Is  block extendable */
+    int ret_value;              /* Return value */
+
+    FUNC_ENTER_NOAPI_NOINIT(H5SH_alloc_extend_cb)
+
+    /* Check if we are allowed to extend this heap block */
+    if(record->len < ex_info->max_extend_size) {
+        H5BT_blk_info_t free_block;     /* Block info for free space */
+        hsize_t space_needed;           /* Space needed to extend block */
+        hbool_t use_free_space = FALSE; /* Flag to indicate that free space should be used */
+
+        /* Set the amount of space needed */
+        space_needed = ex_info->space_needed;
+
+        /* Find first free space block before end of extendable block */
+        free_block.addr = HADDR_UNDEF;
+        if(H5BT_neighbor(ex_info->f, ex_info->dxpl_id, ex_info->bt_free_addr,
+                H5BT_COMPARE_LESS, (record->addr + record->len + 1),
+                &free_block) < 0)
+            HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, H5BT_ITER_ERROR, "can't search for free space")
+            
+        /* Check if we can use free space for part of block to allocate */
+        if(H5F_addr_defined(free_block.addr) &&
+                (free_block.addr + free_block.len) == (record->addr + record->len)) {
+            use_free_space = TRUE;
+            space_needed -= free_block.len;
+        } /* end if */
+
+        /* Check if this heap block can be extended */
+        if((extendable = H5MF_can_extend(ex_info->f, ex_info->file_mem_type,
+                record->addr, record->len, space_needed)) == TRUE) {
+
+            /* Extend heap block in the file */
+            if(H5MF_extend(ex_info->f, ex_info->file_mem_type,
+                    record->addr, record->len, space_needed) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, H5BT_ITER_ERROR, "can't extend extendable heap block?")
+
+            /* Set information to return from iterator */
+            if(use_free_space) {
+                /* Remove block from free space tracker */
+                if(H5BT_remove(ex_info->f, ex_info->dxpl_id, ex_info->bt_free_addr,
+                        free_block.addr, free_block.len) < 0)
+                    HGOTO_ERROR(H5E_HEAP, H5E_CANTDELETE, FAIL, "can't remove free space block")
+
+                ex_info->loc = free_block.addr;
+            } /* end if */
+            else
+                ex_info->loc = record->addr + record->len;
+
+            /* Set information about extension to block */
+            ex_info->extend_addr = record->addr + record->len;
+            ex_info->extend_size = space_needed;
+
+            ret_value = H5BT_ITER_STOP;
+        } /* end if */
+        else if(extendable == FALSE)
+            ret_value = H5BT_ITER_CONT;
+        else
+            HGOTO_ERROR(H5E_HEAP, H5E_CANTCOMPARE, H5BT_ITER_ERROR, "can't check if heap block is extendable")
+    } /* end if */
+    else
+        ret_value = H5BT_ITER_CONT;
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5SH_alloc_extend_cb() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5SH_alloc
+ *
+ * Purpose:	Allocate space for a new object in a segmented heap
+ *
+ * Return:	Non-negative on success (with address of new object
+ *              filled in), negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Mar 25 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5SH_alloc(H5F_t *f, hid_t dxpl_id, haddr_t addr, hsize_t size, haddr_t *obj_addr_p)
+{
+    H5SH_t *sh = NULL;          /* Segmented heap info */
+    haddr_t free_addr;          /* Address of free block */
+    hsize_t free_len;           /* Address of free block */
+    herr_t ret_value=SUCCEED;   /* Return value */
+
+    FUNC_ENTER_NOAPI(H5SH_alloc, FAIL)
+
+    /*
+     * Check arguments.
+     */
+    HDassert(f);
+
+    /* Look up the segmented heap */
+    if (NULL == (sh = H5AC_protect(f, dxpl_id, H5AC_SGHP, addr, NULL, NULL, H5AC_WRITE)))
+	HGOTO_ERROR(H5E_HEAP, H5E_CANTPROTECT, FAIL, "unable to load segmented heap info")
+
+    /* Check for block of at least 'size' bytes in free list */
+    free_addr = HADDR_UNDEF;
+    if (H5BT_locate(f, dxpl_id, sh->bt_free_addr, size, &free_addr, &free_len) < 0)
+	HGOTO_ERROR(H5E_HEAP, H5E_NOTFOUND, FAIL, "error searching segmented heap free list")
+
+    /* Check for finding large enough free block */
+    if (H5F_addr_defined(free_addr)) {
+        /* Remove block from free list */
+        if (H5BT_remove(f, dxpl_id, sh->bt_free_addr, free_addr, size) < 0)
+            HGOTO_ERROR(H5E_HEAP, H5E_CANTDELETE, FAIL, "can't remove block")
+
+        /* Set address to return */
+        *obj_addr_p = free_addr;
+    } /* end if */
+    else {
+        H5SH_extend_t ex_info;
+
+        /* Iterate over the existing heap blocks, to check for extending one */
+        ex_info.f = f;
+        ex_info.dxpl_id = dxpl_id;
+        ex_info.file_mem_type = sh->file_mem_type;
+        ex_info.bt_free_addr = sh->bt_free_addr;
+        ex_info.max_extend_size = sh->max_extend_size;
+        ex_info.space_needed = size;
+        ex_info.loc = HADDR_UNDEF;
+        if(H5BT_iterate(f, dxpl_id, sh->bt_heap_addr, H5SH_alloc_extend_cb, &ex_info) < 0)
+            HGOTO_ERROR(H5E_HEAP, H5E_NOTFOUND, FAIL, "can't iterate over heap blocks")
+
+        /* Check if we managed to extend a heap block */
+        if(H5F_addr_defined(ex_info.loc)) {
+            if(H5BT_insert(f, dxpl_id, sh->bt_heap_addr, ex_info.extend_addr, ex_info.extend_size) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_CANTINSERT, FAIL, "can't extend tracked block")
+
+            /* Set address to return */
+            *obj_addr_p = ex_info.loc;
+        } /* end if */
+        else {
+            haddr_t block_addr;         /* Address of new heap block */
+            hsize_t block_size;         /* Size of heap block */
+
+            /* Determine how large to make the heap block initially */
+            if(size <= sh->min_size)
+                block_size = sh->min_size;
+            else
+                block_size = size;
+
+            /* There's no internal or external space available, allocate a new heap block */
+            if(HADDR_UNDEF == (block_addr = H5MF_alloc(f, sh->file_mem_type, dxpl_id, sh->min_size)))
+                HGOTO_ERROR(H5E_HEAP, H5E_NOSPACE, FAIL, "failed to allocate space for new heap block")
+
+            /* Add heap block to tracker */
+            if(H5BT_insert(f, dxpl_id, sh->bt_heap_addr, block_addr, block_size) < 0)
+                HGOTO_ERROR(H5E_HEAP, H5E_CANTINSERT, FAIL, "can't insert heap block")
+
+            /* Check if there is free space */
+            if(size < sh->min_size) {
+                /* Add free space to tracker */
+                if(H5BT_insert(f, dxpl_id, sh->bt_free_addr, block_addr + size, sh->min_size - size) < 0)
+                    HGOTO_ERROR(H5E_HEAP, H5E_CANTINSERT, FAIL, "can't insert free space")
+            } /* end if */
+
+            /* Set address to return */
+            *obj_addr_p = block_addr;
+        } /* end else */
+    } /* end else */
+
+done:
+    /* Release the block tracker info */
+    if (sh && H5AC_unprotect(f, dxpl_id, H5AC_SGHP, addr, sh, H5AC__NO_FLAGS_SET) < 0)
+        HDONE_ERROR(H5E_HEAP, H5E_CANTUNPROTECT, FAIL, "unable to release segmented heap info")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5SH_alloc() */
+
diff --git a/src/H5SHcache.c b/src/H5SHcache.c
new file mode 100644
index 0000000..e8cdf30
--- /dev/null
+++ b/src/H5SHcache.c
@@ -0,0 +1,332 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * 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 files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic HDF5 document set and   *
+ * is linked from the top-level documents page.  It can also be found at     *
+ * http://hdf.ncsa.uiuc.edu/HDF5/doc/Copyright.html.  If you do not have     *
+ * access to either file, you may request a copy from hdfhelp@ncsa.uiuc.edu. *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*-------------------------------------------------------------------------
+ *
+ * Created:		H5SHcache.c
+ *			Mar 10 2005
+ *			Quincey Koziol <koziol@ncsa.uiuc.edu>
+ *
+ * Purpose:		Implement segmented heap metadata cache methods.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#define H5SH_PACKAGE		/*suppress error about including H5SHpkg  */
+
+/* Private headers */
+#include "H5private.h"		/* Generic Functions			*/
+#include "H5SHpkg.h"		/* Segmented heap			*/
+#include "H5Eprivate.h"		/* Error handling		  	*/
+
+/* Local macros */
+
+/* Segmented heap format version #'s */
+#define H5SH_VERSION 0
+
+
+/* Local typedefs */
+
+/* Local prototypes */
+
+/* Metadata cache callbacks */
+static H5SH_t *H5SH_cache_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, const void *_type, void *udata);
+static herr_t H5SH_cache_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5SH_t *s);
+static herr_t H5SH_cache_clear(H5F_t *f, H5SH_t *s, hbool_t destroy);
+static herr_t H5SH_cache_size(const H5F_t *f, const H5SH_t *s, size_t *size_ptr);
+
+/* Package variables */
+
+/* H5SH inherits cache-like properties from H5AC */
+const H5AC_class_t H5AC_SGHP[1] = {{
+    H5AC_SHEAP_ID,
+    (H5AC_load_func_t)H5SH_cache_load,
+    (H5AC_flush_func_t)H5SH_cache_flush,
+    (H5AC_dest_func_t)H5SH_cache_dest,
+    (H5AC_clear_func_t)H5SH_cache_clear,
+    (H5AC_size_func_t)H5SH_cache_size,
+}};
+
+/* Static variables */
+
+/* Declare a free list to manage segmented heap data to/from disk */
+H5FL_BLK_DEFINE_STATIC(info_block);
+
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5SH_cache_load
+ *
+ * Purpose:	Loads segmented heap info from the disk.
+ *
+ * Return:	Success:	Pointer to a new segmented heap
+ *
+ *		Failure:	NULL
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Mar 23 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static H5SH_t *
+H5SH_cache_load(H5F_t *f, hid_t dxpl_id, haddr_t addr, const void UNUSED *udata1, void UNUSED *udata2)
+{
+    H5SH_t		*sh = NULL;
+    size_t		size;
+    uint8_t		*buf = NULL;
+    uint8_t		*p;             /* Pointer into raw data buffer */
+    H5SH_t		*ret_value;
+
+    FUNC_ENTER_NOAPI(H5SH_cache_load, NULL)
+
+    /* Check arguments */
+    HDassert(f);
+    HDassert(H5F_addr_defined(addr));
+
+    if (NULL==(sh = H5FL_MALLOC(H5SH_t)))
+	HGOTO_ERROR (H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed")
+    HDmemset(&sh->cache_info,0,sizeof(H5AC_info_t));
+
+    /* Compute the size of the segmented heap info on disk */
+    size = H5SH_SIZE(f);
+
+    /* Allocate temporary buffer */
+    if ((buf=H5FL_BLK_MALLOC(info_block,size))==NULL)
+        HGOTO_ERROR (H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed");
+
+    /* Read info from disk */
+    if (H5F_block_read(f, H5FD_MEM_SHEAP_HDR, addr, size, dxpl_id, buf)<0)
+	HGOTO_ERROR(H5E_HEAP, H5E_READERROR, NULL, "can't read segmented heap info")
+
+    p = buf;
+
+    /* magic number */
+    if (HDmemcmp(p, H5SH_MAGIC, H5SH_SIZEOF_MAGIC))
+	HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, NULL, "wrong segmented heap info signature")
+    p += H5SH_SIZEOF_MAGIC;
+
+    /* version */
+    if (*p++ != H5SH_VERSION)
+	HGOTO_ERROR(H5E_HEAP, H5E_CANTLOAD, NULL, "wrong segmented heap info version")
+
+    /* Type of data in heap blocks */
+    sh->heap_type = *p++;
+    if(sh->heap_type == H5SH_RAW)
+        sh->file_mem_type = H5FD_MEM_DRAW;
+    else
+        sh->file_mem_type = H5FD_MEM_SHEAP_BLOCK;
+
+    /* Total heap block minimum size */
+    H5F_DECODE_LENGTH(f, p, sh->min_size);
+
+    /* Total heap block max. expand size */
+    H5F_DECODE_LENGTH(f, p, sh->max_extend_size);
+
+    /* Address of block tracker for heap blocks */
+    H5F_addr_decode(f, (const uint8_t **)&p, &(sh->bt_heap_addr));
+
+    /* Address of block tracker for free space */
+    H5F_addr_decode(f, (const uint8_t **)&p, &(sh->bt_free_addr));
+
+    /* Set return value */
+    ret_value = sh;
+
+done:
+    if(buf)
+        H5FL_BLK_FREE(info_block,buf);
+    if (!ret_value && sh)
+        (void)H5SH_cache_dest(f,sh);
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5SH_cache_load() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5SH_cache_flush
+ *
+ * Purpose:	Flushes dirty segmented heap info to disk.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Mar 23 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5SH_cache_flush(H5F_t *f, hid_t dxpl_id, hbool_t destroy, haddr_t addr, H5SH_t *sh)
+{
+    herr_t      ret_value = SUCCEED;    /* Return value */
+
+    FUNC_ENTER_NOAPI(H5SH_cache_flush, FAIL)
+
+    /* check arguments */
+    HDassert(f);
+    HDassert(H5F_addr_defined(addr));
+    HDassert(sh);
+
+    if (sh->cache_info.is_dirty) {
+        uint8_t	*buf = NULL;
+        uint8_t *p;                 /* Pointer into raw data buffer */
+        size_t	size;
+
+        /* Compute the size of the segmented heap info on disk */
+        size = H5SH_SIZE(f);
+
+        /* Allocate temporary buffer */
+        if ((buf=H5FL_BLK_MALLOC(info_block,size))==NULL)
+            HGOTO_ERROR (H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed");
+
+        p = buf;
+
+        /* magic number */
+        HDmemcpy(p, H5SH_MAGIC, H5SH_SIZEOF_MAGIC);
+        p += H5SH_SIZEOF_MAGIC;
+
+        /* version # */
+        *p++ = H5SH_VERSION;
+
+        /* Type of data in heap blocks */
+        *p++ = (uint8_t)sh->heap_type;
+
+        /* Min. size of heap block */
+        H5F_ENCODE_LENGTH(f, p, sh->min_size);
+
+        /* Max. size to expand heap block */
+        H5F_ENCODE_LENGTH(f, p, sh->max_extend_size);
+
+        /* Address of block tracker for heap blocks */
+        H5F_addr_encode(f, &p, sh->bt_heap_addr);
+
+        /* Address of block tracker for free space */
+        H5F_addr_encode(f, &p, sh->bt_free_addr);
+
+	/* Write the segmented heap info. */
+	if (H5F_block_write(f, H5FD_MEM_SHEAP_HDR, addr, size, dxpl_id, buf) < 0)
+	    HGOTO_ERROR(H5E_HEAP, H5E_CANTFLUSH, FAIL, "unable to save segmented heap info to disk")
+
+        H5FL_BLK_FREE(info_block,buf);
+
+	sh->cache_info.is_dirty = FALSE;
+    } /* end if */
+
+    if (destroy)
+        if (H5SH_cache_dest(f,sh) < 0)
+	    HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy segmented heap info")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* H5SH_cache_flush() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5SH_cache_dest
+ *
+ * Purpose:	Destroys a segmented heap in memory.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Mar 23 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+/* ARGSUSED */
+herr_t
+H5SH_cache_dest(H5F_t UNUSED *f, H5SH_t *sh)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5SH_cache_dest)
+
+    /*
+     * Check arguments.
+     */
+    HDassert(sh);
+
+    /* Free segmented heap info */
+    H5FL_FREE(H5SH_t,sh);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* end H5SH_cache_dest() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5SH_cache_clear
+ *
+ * Purpose:	Mark a segmented heap info in memory as non-dirty.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Mar 23 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5SH_cache_clear(H5F_t *f, H5SH_t *sh, hbool_t destroy)
+{
+    herr_t ret_value = SUCCEED;
+
+    FUNC_ENTER_NOAPI_NOINIT(H5SH_cache_clear)
+
+    /*
+     * Check arguments.
+     */
+    HDassert(sh);
+
+    /* Reset the dirty flag.  */
+    sh->cache_info.is_dirty = FALSE;
+ 
+    if (destroy)
+        if (H5SH_cache_dest(f, sh) < 0)
+	    HGOTO_ERROR(H5E_HEAP, H5E_CANTFREE, FAIL, "unable to destroy segmented heap info")
+
+done:
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5SH_cache_clear() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5SH_cache_size
+ *
+ * Purpose:	Compute the size in bytes of a segmented heap info
+ *		on disk, and return it in *size_ptr.  On failure, 
+ *		the value of *size_ptr is undefined.
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Mar 23 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+static herr_t
+H5SH_cache_size(const H5F_t *f, const H5SH_t UNUSED *sh, size_t *size_ptr)
+{
+    FUNC_ENTER_NOAPI_NOINIT_NOFUNC(H5SH_cache_size)
+
+    /* check arguments */
+    HDassert(f);
+    HDassert(size_ptr);
+
+    /* Set size value */
+    *size_ptr = H5SH_SIZE(f);
+
+    FUNC_LEAVE_NOAPI(SUCCEED)
+} /* H5SH_cache_size() */
+
+
diff --git a/src/H5SHdbg.c b/src/H5SHdbg.c
new file mode 100644
index 0000000..42b2769
--- /dev/null
+++ b/src/H5SHdbg.c
@@ -0,0 +1,96 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * 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 files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic HDF5 document set and   *
+ * is linked from the top-level documents page.  It can also be found at     *
+ * http://hdf.ncsa.uiuc.edu/HDF5/doc/Copyright.html.  If you do not have     *
+ * access to either file, you may request a copy from hdfhelp@ncsa.uiuc.edu. *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*-------------------------------------------------------------------------
+ *
+ * Created:		H5SHdbg.c
+ *			Mar 24 2005
+ *			Quincey Koziol <koziol@ncsa.uiuc.edu>
+ *
+ * Purpose:		Dump debugging information about a segmented heap
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#define H5SH_PACKAGE		/*suppress error about including H5SHpkg  */
+
+/* Private headers */
+#include "H5private.h"		/* Generic Functions			*/
+#include "H5Eprivate.h"		/* Error handling		  	*/
+#include "H5SHpkg.h"		/* Segmented heap			*/
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5SH_debug
+ *
+ * Purpose:	Prints debugging info about a segmented heap
+ *
+ * Return:	Non-negative on success/Negative on failure
+ *
+ * Programmer:	Quincey Koziol
+ *		koziol@ncsa.uiuc.edu
+ *		Mar 24 2005
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5SH_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream, int indent, int fwidth)
+{
+    H5SH_t	*sh = NULL;
+    herr_t      ret_value=SUCCEED;       /* Return value */
+
+    FUNC_ENTER_NOAPI(H5SH_debug, FAIL)
+
+    /*
+     * Check arguments.
+     */
+    assert(f);
+    assert(H5F_addr_defined(addr));
+    assert(stream);
+    assert(indent >= 0);
+    assert(fwidth >= 0);
+
+    /*
+     * Load the segmented heap info
+     */
+    if (NULL == (sh = H5AC_protect(f, dxpl_id, H5AC_SGHP, addr, NULL, NULL, H5AC_READ)))
+	HGOTO_ERROR(H5E_BTREE, H5E_CANTLOAD, FAIL, "unable to load segmented heap info")
+
+    /*
+     * Print the values.
+     */
+    HDfprintf(stream, "%*s%-*s %s\n", indent, "", fwidth,
+	      "Dirty flag:",
+	      sh->cache_info.is_dirty ? "True" : "False");
+    HDfprintf(stream, "%*s%-*s %Hu\n", indent, "", fwidth,
+	      "Minimum Size Of Heap Blocks:",
+	      sh->min_size);
+    HDfprintf(stream, "%*s%-*s %Hu\n", indent, "", fwidth,
+	      "Maximum Size To Extend Heap Blocks:",
+	      sh->max_extend_size);
+    HDfprintf(stream, "%*s%-*s %a\n", indent, "", fwidth,
+	      "Address of Block Tracker For Heap Blocks:",
+	      sh->bt_heap_addr);
+    HDfprintf(stream, "%*s%-*s %a\n", indent, "", fwidth,
+	      "Address of Block Tracker For Free Space:",
+	      sh->bt_free_addr);
+
+done:
+    if (sh && H5AC_unprotect(f, dxpl_id, H5AC_SGHP, addr, sh, H5AC__NO_FLAGS_SET) < 0)
+        HDONE_ERROR(H5E_BTREE, H5E_PROTECT, FAIL, "unable to release segmented heap info")
+
+    FUNC_LEAVE_NOAPI(ret_value)
+} /* end H5SH_debug() */
+
+
diff --git a/src/H5SHpkg.h b/src/H5SHpkg.h
new file mode 100644
index 0000000..9b38a4f
--- /dev/null
+++ b/src/H5SHpkg.h
@@ -0,0 +1,103 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * 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 files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic HDF5 document set and   *
+ * is linked from the top-level documents page.  It can also be found at     *
+ * http://hdf.ncsa.uiuc.edu/HDF5/doc/Copyright.html.  If you do not have     *
+ * access to either file, you may request a copy from hdfhelp@ncsa.uiuc.edu. *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*
+ * Programmer:	Quincey Koziol <koziol@ncsa.uiuc.edu>
+ *		Thursday, March 10, 2005
+ *
+ * Purpose:	This file contains declarations which are visible only within
+ *		the H5SH package.  Source files outside the H5SH package should
+ *		include H5SHprivate.h instead.
+ */
+#ifndef H5SH_PACKAGE
+#error "Do not include this file outside the H5SH package!"
+#endif
+
+#ifndef _H5SHpkg_H
+#define _H5SHpkg_H
+
+/* Get package's private header */
+#include "H5ACprivate.h"	/* Metadata cache			*/
+#include "H5FLprivate.h"	/* Free Lists                           */
+#include "H5SHprivate.h"	/* Segmented heap			*/
+
+/* Other private headers needed by this file */
+
+/**************************/
+/* Package Private Macros */
+/**************************/
+
+/* Size of signature information (on disk) */
+#define H5SH_SIZEOF_MAGIC               4
+
+/* Segmented heap signature */
+#define H5SH_MAGIC                      "SGHP"
+
+/* Size of the segmented heap info on disk */
+#define H5SH_SIZE(f) (                                                        \
+    4 +                         /* Signature */                               \
+    1 +                         /* Version */                                 \
+    1 +                         /* Heap data type */                          \
+    H5F_SIZEOF_SIZE(f) +        /* Min. size of heap blocks */                \
+    H5F_SIZEOF_SIZE(f) +        /* Max. expand size of heap blocks */         \
+    H5F_SIZEOF_ADDR(f) +        /* Address of block tracker for actual heap blocks */ \
+    H5F_SIZEOF_ADDR(f))         /* Address of block tracker for free blocks */
+
+/****************************/
+/* Package Private Typedefs */
+/****************************/
+
+/* The segmented heap information */
+typedef struct H5SH_t {
+    /* Information for H5AC cache functions, _must_ be first field in structure */
+    H5AC_info_t cache_info;
+
+    /* Information set by user */
+    H5SH_data_type_t heap_type; /* Type of data stored in heap */
+    hsize_t     min_size;       /* Minimum size of heap block */
+    hsize_t     max_extend_size;/* Maximum size to expand heap block to */
+                                /* (Objects larger than this size will get
+                                 * placed into their own heap block)
+                                 */
+
+    /* Derived information from user's information */
+    H5FD_mem_t file_mem_type;   /* Type of memory to store heap blocks in the file */
+
+    /* Internal block tracking information */
+    haddr_t     bt_heap_addr;   /* Address of block tracker for heap blocks */
+    haddr_t     bt_free_addr;   /* Address of block tracker for free space */
+} H5SH_t;
+
+
+/*****************************/
+/* Package Private Variables */
+/*****************************/
+
+/* H5SH inherits cache-like properties from H5AC */
+H5_DLLVAR const H5AC_class_t H5AC_SGHP[1];
+
+/* Declare a free list to manage the H5SH_t struct */
+H5FL_EXTERN(H5SH_t);
+
+
+/******************************/
+/* Package Private Prototypes */
+/******************************/
+H5_DLL herr_t H5SH_cache_dest(H5F_t *f, H5SH_t *b);
+H5_DLL herr_t H5SH_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE *stream,
+    int indent, int fwidth);
+
+#endif /* _H5SHpkg_H */
+
+
diff --git a/src/H5SHprivate.h b/src/H5SHprivate.h
new file mode 100644
index 0000000..b6f2306
--- /dev/null
+++ b/src/H5SHprivate.h
@@ -0,0 +1,59 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * 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 files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic HDF5 document set and   *
+ * is linked from the top-level documents page.  It can also be found at     *
+ * http://hdf.ncsa.uiuc.edu/HDF5/doc/Copyright.html.  If you do not have     *
+ * access to either file, you may request a copy from hdfhelp@ncsa.uiuc.edu. *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*-------------------------------------------------------------------------
+ *
+ * Created:		H5SHprivate.h
+ *			Mar 10 2005
+ *			Quincey Koziol <koziol@ncsa.uiuc.edu>
+ *
+ * Purpose:		Private header for library accessible segmented heap routines.
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#ifndef _H5SHprivate_H
+#define _H5SHprivate_H
+
+/* Include package's public header */
+#include "H5SHpublic.h"
+
+/* Private headers needed by this file */
+#include "H5Fprivate.h"		/* File access				*/
+
+/**************************/
+/* Library Private Macros */
+/**************************/
+
+     
+/****************************/
+/* Library Private Typedefs */
+/****************************/
+
+/* Type of data in heap */
+typedef enum H5SH_data_type_t {
+    H5SH_RAW,	        /* Heap data is "raw data" from dataset */
+    H5SH_META	        /* Heap data is metadata about file's structure */
+} H5SH_data_type_t;
+
+/***************************************/
+/* Library-private Function Prototypes */
+/***************************************/
+H5_DLL herr_t H5SH_create(H5F_t *f, hid_t dxpl_id, haddr_t *addr_p,
+    H5SH_data_type_t heap_type, hsize_t min_size, hsize_t max_extend_size);
+H5_DLL herr_t H5SH_alloc(H5F_t *f, hid_t dxpl_id, haddr_t addr, hsize_t size,
+    haddr_t *obj_addr_p);
+
+#endif /* _H5SHprivate_H */
+
diff --git a/src/H5SHpublic.h b/src/H5SHpublic.h
new file mode 100644
index 0000000..2bab6bf
--- /dev/null
+++ b/src/H5SHpublic.h
@@ -0,0 +1,53 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * 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 files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic HDF5 document set and   *
+ * is linked from the top-level documents page.  It can also be found at     *
+ * http://hdf.ncsa.uiuc.edu/HDF5/doc/Copyright.html.  If you do not have     *
+ * access to either file, you may request a copy from hdfhelp@ncsa.uiuc.edu. *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/*-------------------------------------------------------------------------
+ *
+ * Created:             H5SHpublic.h
+ *                      Mar 23 2005
+ *                      Quincey Koziol <koziol@ncsa.uiuc.edu>
+ *
+ * Purpose:             Public declarations for the H5SH package.
+ *
+ *-------------------------------------------------------------------------
+ */
+#ifndef _H5SHpublic_H
+#define _H5SHpublic_H
+
+/* Public headers needed by this file */
+#include "H5public.h"
+
+/*****************/
+/* Public Macros */
+/*****************/
+
+/*******************/
+/* Public Typedefs */
+/*******************/
+
+/**********************************/
+/* Public API Function Prototypes */
+/**********************************/
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _H5SHpublic_H */
+
+
diff --git a/src/Makefile.am b/src/Makefile.am
index bdb7887..1dbdaed 100755
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -58,7 +58,8 @@ libhdf5_la_SOURCES= H5.c H5A.c H5AC.c H5B.c H5B2.c H5B2cache.c H5B2dbg.c      \
         H5Oname.c H5Onull.c H5Opline.c H5Osdspace.c H5Oshared.c H5Ostab.c     \
         H5P.c H5Pdcpl.c H5Pdxpl.c H5Pfapl.c H5Pfcpl.c H5Ptest.c H5R.c H5RC.c  \
         H5RS.c H5S.c H5Sall.c H5Shyper.c H5Smpio.c H5Snone.c H5Spoint.c       \
-        H5Sselect.c H5Stest.c H5SL.c H5ST.c H5T.c H5Tarray.c H5Tbit.c H5Tcommit.c \
+        H5Sselect.c H5Stest.c H5SH.c H5SHcache.c H5SHdbg.c \
+        H5SL.c H5ST.c H5T.c H5Tarray.c H5Tbit.c H5Tcommit.c \
         H5Tcompound.c H5Tconv.c H5Tcset.c H5Tenum.c H5Tfields.c H5Tfixed.c    \
         H5Tfloat.c H5Tinit.c H5Tnative.c H5Toffset.c H5Topaque.c H5Torder.c   \
         H5Tpad.c H5Tprecis.c H5Tstrpad.c H5Tvlen.c H5TS.c H5V.c H5Z.c  \
@@ -73,7 +74,8 @@ include_HEADERS =H5public.h H5Apublic.h H5ACpublic.h H5Bpublic.h H5B2public.h \
         H5FDfphdf5.h H5FDlog.h H5FDmpi.h H5FDmpio.h H5FDmpiposix.h              \
         H5FDmulti.h H5FDsec2.h $(SRB_HEADER) H5FDstdio.h H5FDstream.h H5FPpublic.h             \
         H5Gpublic.h H5HGpublic.h H5HLpublic.h H5Ipublic.h                     \
-        H5MMpublic.h H5Opublic.h H5Ppublic.h H5Rpublic.h H5Spublic.h          \
+        H5MMpublic.h H5Opublic.h H5Ppublic.h H5Rpublic.h H5Spublic.h \
+        H5SHpublic.h \
         H5Tpublic.h H5Zpublic.h H5pubconf.h hdf5.h H5api_adpt.h
 
 # Private headers
@@ -84,7 +86,8 @@ include_HEADERS =H5public.h H5Apublic.h H5ACpublic.h H5Bpublic.h H5B2public.h \
 #        H5FOprivate.h H5FSprivate.h H5Gprivate.h H5Gpkg.h                     \
 #        H5HGprivate.h H5HLprivate.h H5HPprivate.h H5Iprivate.h H5MFprivate.h  \
 #        H5MMprivate.h H5Oprivate.h H5Opkg.h H5Pprivate.h H5Ppkg.h             \
-#        H5Rprivate.h H5RCprivate.h H5RSprivate.h H5Sprivate.h H5STprivate.h   \
+#        H5Rprivate.h H5RCprivate.h H5RSprivate.h H5Sprivate.h H5SHprivate.h \
+#        H5STprivate.h \
 #        H5Tprivate.h H5Tpkg.h H5TSprivate.h H5Vprivate.h        \
 #        H5Zprivate.h H5Zpkg.h H5config.h
 
diff --git a/src/Makefile.in b/src/Makefile.in
index 4abb990..8223a0b 100644
--- a/src/Makefile.in
+++ b/src/Makefile.in
@@ -96,12 +96,13 @@ am__libhdf5_la_SOURCES_DIST = H5.c H5A.c H5AC.c H5B.c H5B2.c \
 	H5Oshared.c H5Ostab.c H5P.c H5Pdcpl.c H5Pdxpl.c H5Pfapl.c \
 	H5Pfcpl.c H5Ptest.c H5R.c H5RC.c H5RS.c H5S.c H5Sall.c \
 	H5Shyper.c H5Smpio.c H5Snone.c H5Spoint.c H5Sselect.c \
-	H5Stest.c H5SL.c H5ST.c H5T.c H5Tarray.c H5Tbit.c H5Tcommit.c \
-	H5Tcompound.c H5Tconv.c H5Tcset.c H5Tenum.c H5Tfields.c \
-	H5Tfixed.c H5Tfloat.c H5Tinit.c H5Tnative.c H5Toffset.c \
-	H5Topaque.c H5Torder.c H5Tpad.c H5Tprecis.c H5Tstrpad.c \
-	H5Tvlen.c H5TS.c H5V.c H5Z.c H5Zdeflate.c H5Zfletcher32.c \
-	H5Znbit.c H5Zshuffle.c H5Zszip.c H5Zscaleoffset.c H5Ztrans.c
+	H5Stest.c H5SH.c H5SHcache.c H5SHdbg.c H5SL.c H5ST.c H5T.c \
+	H5Tarray.c H5Tbit.c H5Tcommit.c H5Tcompound.c H5Tconv.c \
+	H5Tcset.c H5Tenum.c H5Tfields.c H5Tfixed.c H5Tfloat.c \
+	H5Tinit.c H5Tnative.c H5Toffset.c H5Topaque.c H5Torder.c \
+	H5Tpad.c H5Tprecis.c H5Tstrpad.c H5Tvlen.c H5TS.c H5V.c H5Z.c \
+	H5Zdeflate.c H5Zfletcher32.c H5Znbit.c H5Zshuffle.c H5Zszip.c \
+	H5Zscaleoffset.c H5Ztrans.c
 @BUILD_SRB_CONDITIONAL_TRUE@am__objects_1 = H5FDsrb.lo
 am_libhdf5_la_OBJECTS = H5.lo H5A.lo H5AC.lo H5B.lo H5B2.lo \
 	H5B2cache.lo H5B2dbg.lo H5B2test.lo H5BT.lo H5BTbtree2.lo \
@@ -119,13 +120,14 @@ am_libhdf5_la_OBJECTS = H5.lo H5A.lo H5AC.lo H5B.lo H5B2.lo \
 	H5Oshared.lo H5Ostab.lo H5P.lo H5Pdcpl.lo H5Pdxpl.lo \
 	H5Pfapl.lo H5Pfcpl.lo H5Ptest.lo H5R.lo H5RC.lo H5RS.lo H5S.lo \
 	H5Sall.lo H5Shyper.lo H5Smpio.lo H5Snone.lo H5Spoint.lo \
-	H5Sselect.lo H5Stest.lo H5SL.lo H5ST.lo H5T.lo H5Tarray.lo \
-	H5Tbit.lo H5Tcommit.lo H5Tcompound.lo H5Tconv.lo H5Tcset.lo \
-	H5Tenum.lo H5Tfields.lo H5Tfixed.lo H5Tfloat.lo H5Tinit.lo \
-	H5Tnative.lo H5Toffset.lo H5Topaque.lo H5Torder.lo H5Tpad.lo \
-	H5Tprecis.lo H5Tstrpad.lo H5Tvlen.lo H5TS.lo H5V.lo H5Z.lo \
-	H5Zdeflate.lo H5Zfletcher32.lo H5Znbit.lo H5Zshuffle.lo \
-	H5Zszip.lo H5Zscaleoffset.lo H5Ztrans.lo
+	H5Sselect.lo H5Stest.lo H5SH.lo H5SHcache.lo H5SHdbg.lo \
+	H5SL.lo H5ST.lo H5T.lo H5Tarray.lo H5Tbit.lo H5Tcommit.lo \
+	H5Tcompound.lo H5Tconv.lo H5Tcset.lo H5Tenum.lo H5Tfields.lo \
+	H5Tfixed.lo H5Tfloat.lo H5Tinit.lo H5Tnative.lo H5Toffset.lo \
+	H5Topaque.lo H5Torder.lo H5Tpad.lo H5Tprecis.lo H5Tstrpad.lo \
+	H5Tvlen.lo H5TS.lo H5V.lo H5Z.lo H5Zdeflate.lo \
+	H5Zfletcher32.lo H5Znbit.lo H5Zshuffle.lo H5Zszip.lo \
+	H5Zscaleoffset.lo H5Ztrans.lo
 libhdf5_la_OBJECTS = $(am_libhdf5_la_OBJECTS)
 PROGRAMS = $(noinst_PROGRAMS)
 H5detect_SOURCES = H5detect.c
@@ -153,8 +155,8 @@ am__include_HEADERS_DIST = H5public.h H5Apublic.h H5ACpublic.h \
 	H5FDmpiposix.h H5FDmulti.h H5FDsec2.h H5FDsrb.h H5FDstdio.h \
 	H5FDstream.h H5FPpublic.h H5Gpublic.h H5HGpublic.h \
 	H5HLpublic.h H5Ipublic.h H5MMpublic.h H5Opublic.h H5Ppublic.h \
-	H5Rpublic.h H5Spublic.h H5Tpublic.h H5Zpublic.h H5pubconf.h \
-	hdf5.h H5api_adpt.h
+	H5Rpublic.h H5Spublic.h H5SHpublic.h H5Tpublic.h H5Zpublic.h \
+	H5pubconf.h hdf5.h H5api_adpt.h
 includeHEADERS_INSTALL = $(INSTALL_HEADER)
 HEADERS = $(include_HEADERS)
 ETAGS = etags
@@ -387,7 +389,8 @@ libhdf5_la_SOURCES = H5.c H5A.c H5AC.c H5B.c H5B2.c H5B2cache.c H5B2dbg.c      \
         H5Oname.c H5Onull.c H5Opline.c H5Osdspace.c H5Oshared.c H5Ostab.c     \
         H5P.c H5Pdcpl.c H5Pdxpl.c H5Pfapl.c H5Pfcpl.c H5Ptest.c H5R.c H5RC.c  \
         H5RS.c H5S.c H5Sall.c H5Shyper.c H5Smpio.c H5Snone.c H5Spoint.c       \
-        H5Sselect.c H5Stest.c H5SL.c H5ST.c H5T.c H5Tarray.c H5Tbit.c H5Tcommit.c \
+        H5Sselect.c H5Stest.c H5SH.c H5SHcache.c H5SHdbg.c \
+        H5SL.c H5ST.c H5T.c H5Tarray.c H5Tbit.c H5Tcommit.c \
         H5Tcompound.c H5Tconv.c H5Tcset.c H5Tenum.c H5Tfields.c H5Tfixed.c    \
         H5Tfloat.c H5Tinit.c H5Tnative.c H5Toffset.c H5Topaque.c H5Torder.c   \
         H5Tpad.c H5Tprecis.c H5Tstrpad.c H5Tvlen.c H5TS.c H5V.c H5Z.c  \
@@ -402,7 +405,8 @@ include_HEADERS = H5public.h H5Apublic.h H5ACpublic.h H5Bpublic.h H5B2public.h \
         H5FDfphdf5.h H5FDlog.h H5FDmpi.h H5FDmpio.h H5FDmpiposix.h              \
         H5FDmulti.h H5FDsec2.h $(SRB_HEADER) H5FDstdio.h H5FDstream.h H5FPpublic.h             \
         H5Gpublic.h H5HGpublic.h H5HLpublic.h H5Ipublic.h                     \
-        H5MMpublic.h H5Opublic.h H5Ppublic.h H5Rpublic.h H5Spublic.h          \
+        H5MMpublic.h H5Opublic.h H5Ppublic.h H5Rpublic.h H5Spublic.h \
+        H5SHpublic.h \
         H5Tpublic.h H5Zpublic.h H5pubconf.h hdf5.h H5api_adpt.h
 
 
@@ -414,7 +418,8 @@ include_HEADERS = H5public.h H5Apublic.h H5ACpublic.h H5Bpublic.h H5B2public.h \
 #        H5FOprivate.h H5FSprivate.h H5Gprivate.h H5Gpkg.h                     \
 #        H5HGprivate.h H5HLprivate.h H5HPprivate.h H5Iprivate.h H5MFprivate.h  \
 #        H5MMprivate.h H5Oprivate.h H5Opkg.h H5Pprivate.h H5Ppkg.h             \
-#        H5Rprivate.h H5RCprivate.h H5RSprivate.h H5Sprivate.h H5STprivate.h   \
+#        H5Rprivate.h H5RCprivate.h H5RSprivate.h H5Sprivate.h H5SHprivate.h \
+#        H5STprivate.h \
 #        H5Tprivate.h H5Tpkg.h H5TSprivate.h H5Vprivate.h        \
 #        H5Zprivate.h H5Zpkg.h H5config.h
 
@@ -615,6 +620,9 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5RC.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5RS.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5S.Plo@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5SH.Plo@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5SHcache.Plo@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5SHdbg.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5SL.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5ST.Plo@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/H5Sall.Plo@am__quote@
diff --git a/test/Makefile.am b/test/Makefile.am
index 7935a39..2ba89e3 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -33,12 +33,13 @@ endif
 
 # These are our main targets. They should be listed in the order to be
 # executed, generally most specific tests to least specific tests.
-TEST_PROG=testhdf5 lheap ohdr stab gheap cache hyperslab istore bittests     \
+TEST_PROG=testhdf5 lheap ohdr stab gheap cache btree2 blocktrack sheap \
+           hyperslab istore bittests \
            dtypes dsets cmpd_dset extend external links unlink big mtime     \
            fillval mount flush1 flush2 enum \
-           set_extent ttsafe stream_test       \
+           set_extent ttsafe stream_test \
            getname file_handle ntypes dangle dtransform filename reserved    \
-           btree2 blocktrack $(SRB_TESTS)
+           $(SRB_TESTS)
 
 # List programs to be built when testing here. error_test and err_compat are
 # built at the same time as the other tests, but executed by testerror.sh.
@@ -93,7 +94,7 @@ MOSTLYCLEANFILES=cmpd_dset.h5 compact_dataset.h5 dataset.h5 extend.h5 istore.h5\
             family_file000[0-3][0-9].h5 multi_file-[rs].h5 core_file         \
             new_move_[ab].h5 ntypes.h5 dangle.h5 error_test.h5 err_compat.h5 \
             dtransform.h5 test_filters.h5 get_file_name.h5 tstint[1-2].h5    \
-            unlink_chunked.h5 btree2.h5 blocktrack.h5
+            unlink_chunked.h5 btree2.h5 blocktrack.h5 sheap.h5
 
 # Sources for testhdf5 executable
 testhdf5_SOURCES=testhdf5.c tarray.c tattr.c tconfig.c tfile.c tgenprop.c \
diff --git a/test/Makefile.in b/test/Makefile.in
index 08975d3..89d5e5e 100644
--- a/test/Makefile.in
+++ b/test/Makefile.in
@@ -29,7 +29,7 @@
 #
 # HDF5 Library Test Makefile(.in)
 #
-SOURCES = $(libh5test_la_SOURCES) big.c bittests.c blocktrack.c btree2.c cache.c cmpd_dset.c dangle.c dsets.c dtransform.c dtypes.c enum.c err_compat.c error_test.c extend.c external.c file_handle.c filename.c fillval.c flush1.c flush2.c getname.c gheap.c hyperslab.c istore.c lheap.c links.c mount.c mtime.c ntypes.c ohdr.c reserved.c set_extent.c srb_append.c srb_read.c srb_write.c stab.c stream_test.c $(testhdf5_SOURCES) testmeta.c $(ttsafe_SOURCES) unlink.c
+SOURCES = $(libh5test_la_SOURCES) big.c bittests.c blocktrack.c btree2.c cache.c cmpd_dset.c dangle.c dsets.c dtransform.c dtypes.c enum.c err_compat.c error_test.c extend.c external.c file_handle.c filename.c fillval.c flush1.c flush2.c getname.c gheap.c hyperslab.c istore.c lheap.c links.c mount.c mtime.c ntypes.c ohdr.c reserved.c set_extent.c sheap.c srb_append.c srb_read.c srb_write.c stab.c stream_test.c $(testhdf5_SOURCES) testmeta.c $(ttsafe_SOURCES) unlink.c
 
 srcdir = @srcdir@
 top_srcdir = @top_srcdir@
@@ -74,7 +74,8 @@ libh5test_la_OBJECTS = $(am_libh5test_la_OBJECTS)
 @BUILD_SRB_CONDITIONAL_TRUE@	srb_append$(EXEEXT) \
 @BUILD_SRB_CONDITIONAL_TRUE@	srb_read$(EXEEXT)
 am__EXEEXT_2 = testhdf5$(EXEEXT) lheap$(EXEEXT) ohdr$(EXEEXT) \
-	stab$(EXEEXT) gheap$(EXEEXT) cache$(EXEEXT) hyperslab$(EXEEXT) \
+	stab$(EXEEXT) gheap$(EXEEXT) cache$(EXEEXT) btree2$(EXEEXT) \
+	blocktrack$(EXEEXT) sheap$(EXEEXT) hyperslab$(EXEEXT) \
 	istore$(EXEEXT) bittests$(EXEEXT) dtypes$(EXEEXT) \
 	dsets$(EXEEXT) cmpd_dset$(EXEEXT) extend$(EXEEXT) \
 	external$(EXEEXT) links$(EXEEXT) unlink$(EXEEXT) big$(EXEEXT) \
@@ -83,7 +84,7 @@ am__EXEEXT_2 = testhdf5$(EXEEXT) lheap$(EXEEXT) ohdr$(EXEEXT) \
 	ttsafe$(EXEEXT) stream_test$(EXEEXT) getname$(EXEEXT) \
 	file_handle$(EXEEXT) ntypes$(EXEEXT) dangle$(EXEEXT) \
 	dtransform$(EXEEXT) filename$(EXEEXT) reserved$(EXEEXT) \
-	btree2$(EXEEXT) blocktrack$(EXEEXT) $(am__EXEEXT_1)
+	$(am__EXEEXT_1)
 big_SOURCES = big.c
 big_OBJECTS = big.$(OBJEXT)
 big_LDADD = $(LDADD)
@@ -212,6 +213,10 @@ set_extent_SOURCES = set_extent.c
 set_extent_OBJECTS = set_extent.$(OBJEXT)
 set_extent_LDADD = $(LDADD)
 set_extent_DEPENDENCIES = libh5test.la $(am__DEPENDENCIES_1)
+sheap_SOURCES = sheap.c
+sheap_OBJECTS = sheap.$(OBJEXT)
+sheap_LDADD = $(LDADD)
+sheap_DEPENDENCIES = libh5test.la $(am__DEPENDENCIES_1)
 srb_append_SOURCES = srb_append.c
 srb_append_OBJECTS = srb_append.$(OBJEXT)
 srb_append_LDADD = $(LDADD)
@@ -272,7 +277,7 @@ SOURCES = $(libh5test_la_SOURCES) big.c bittests.c blocktrack.c \
 	dtypes.c enum.c err_compat.c error_test.c extend.c external.c \
 	file_handle.c filename.c fillval.c flush1.c flush2.c getname.c \
 	gheap.c hyperslab.c istore.c lheap.c links.c mount.c mtime.c \
-	ntypes.c ohdr.c reserved.c set_extent.c srb_append.c \
+	ntypes.c ohdr.c reserved.c set_extent.c sheap.c srb_append.c \
 	srb_read.c srb_write.c stab.c stream_test.c \
 	$(testhdf5_SOURCES) testmeta.c $(ttsafe_SOURCES) unlink.c
 DIST_SOURCES = $(libh5test_la_SOURCES) big.c bittests.c blocktrack.c \
@@ -280,7 +285,7 @@ DIST_SOURCES = $(libh5test_la_SOURCES) big.c bittests.c blocktrack.c \
 	dtypes.c enum.c err_compat.c error_test.c extend.c external.c \
 	file_handle.c filename.c fillval.c flush1.c flush2.c getname.c \
 	gheap.c hyperslab.c istore.c lheap.c links.c mount.c mtime.c \
-	ntypes.c ohdr.c reserved.c set_extent.c srb_append.c \
+	ntypes.c ohdr.c reserved.c set_extent.c sheap.c srb_append.c \
 	srb_read.c srb_write.c stab.c stream_test.c \
 	$(testhdf5_SOURCES) testmeta.c $(ttsafe_SOURCES) unlink.c
 ETAGS = etags
@@ -492,12 +497,13 @@ check_SCRIPTS = $(TEST_SCRIPT)
 
 # These are our main targets. They should be listed in the order to be
 # executed, generally most specific tests to least specific tests.
-TEST_PROG = testhdf5 lheap ohdr stab gheap cache hyperslab istore bittests     \
+TEST_PROG = testhdf5 lheap ohdr stab gheap cache btree2 blocktrack sheap \
+           hyperslab istore bittests \
            dtypes dsets cmpd_dset extend external links unlink big mtime     \
            fillval mount flush1 flush2 enum \
-           set_extent ttsafe stream_test       \
+           set_extent ttsafe stream_test \
            getname file_handle ntypes dangle dtransform filename reserved    \
-           btree2 blocktrack $(SRB_TESTS)
+           $(SRB_TESTS)
 
 
 # The libh5test.a library provides common support code for the tests.
@@ -536,7 +542,7 @@ MOSTLYCLEANFILES = cmpd_dset.h5 compact_dataset.h5 dataset.h5 extend.h5 istore.h
             family_file000[0-3][0-9].h5 multi_file-[rs].h5 core_file         \
             new_move_[ab].h5 ntypes.h5 dangle.h5 error_test.h5 err_compat.h5 \
             dtransform.h5 test_filters.h5 get_file_name.h5 tstint[1-2].h5    \
-            unlink_chunked.h5 btree2.h5 blocktrack.h5
+            unlink_chunked.h5 btree2.h5 blocktrack.h5 sheap.h5
 
 
 # Sources for testhdf5 executable
@@ -704,6 +710,9 @@ reserved$(EXEEXT): $(reserved_OBJECTS) $(reserved_DEPENDENCIES)
 set_extent$(EXEEXT): $(set_extent_OBJECTS) $(set_extent_DEPENDENCIES) 
 	@rm -f set_extent$(EXEEXT)
 	$(LINK) $(set_extent_LDFLAGS) $(set_extent_OBJECTS) $(set_extent_LDADD) $(LIBS)
+sheap$(EXEEXT): $(sheap_OBJECTS) $(sheap_DEPENDENCIES) 
+	@rm -f sheap$(EXEEXT)
+	$(LINK) $(sheap_LDFLAGS) $(sheap_OBJECTS) $(sheap_LDADD) $(LIBS)
 srb_append$(EXEEXT): $(srb_append_OBJECTS) $(srb_append_DEPENDENCIES) 
 	@rm -f srb_append$(EXEEXT)
 	$(LINK) $(srb_append_LDFLAGS) $(srb_append_OBJECTS) $(srb_append_LDADD) $(LIBS)
@@ -771,6 +780,7 @@ distclean-compile:
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/ohdr.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/reserved.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/set_extent.Po@am__quote@
+@AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/sheap.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/srb_append.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/srb_read.Po@am__quote@
 @AMDEP_TRUE@@am__include@ @am__quote@./$(DEPDIR)/srb_write.Po@am__quote@
diff --git a/test/sheap.c b/test/sheap.c
new file mode 100644
index 0000000..f2b7e00
--- /dev/null
+++ b/test/sheap.c
@@ -0,0 +1,259 @@
+/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
+ * Copyright by the Board of Trustees of the University of Illinois.         *
+ * 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 files COPYING and Copyright.html.  COPYING can be found at the root   *
+ * of the source code distribution tree; Copyright.html can be found at the  *
+ * root level of an installed copy of the electronic HDF5 document set and   *
+ * is linked from the top-level documents page.  It can also be found at     *
+ * http://hdf.ncsa.uiuc.edu/HDF5/doc/Copyright.html.  If you do not have     *
+ * access to either file, you may request a copy from hdfhelp@ncsa.uiuc.edu. *
+ * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
+
+/* Programmer:  Quincey Koziol <koziol@ncsa.uiuc.edu>
+ *              Wednesday, March 23, 2005
+ */
+#include "h5test.h"
+
+/*
+ * This file needs to access private datatypes from the H5SH package.
+ * This file also needs to access the segmented heap testing code.
+ */
+#define H5SH_PACKAGE
+#define H5SH_TESTING
+#include "H5SHpkg.h"
+
+/* Other private headers that this test requires */
+#include "H5Iprivate.h"
+
+const char *FILENAME[] = {
+    "sheap",
+    NULL
+};
+
+#define SHEAP_TYPE H5SH_META
+#define SHEAP_MIN_SIZE  4096
+#define SHEAP_MAX_EXPAND_SIZE  65536
+
+
+/*-------------------------------------------------------------------------
+ * Function:	test_create
+ *
+ * Purpose:	Basic tests for the segmented heap code
+ *
+ * Return:	Success:	0
+ *
+ *		Failure:	1
+ *
+ * Programmer:	Quincey Koziol
+ *              Wednesday, March 23, 2005
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+static int
+test_create(hid_t fapl)
+{
+    hid_t	file=-1;
+    char	filename[1024];
+    H5F_t	*f=NULL;
+    haddr_t     sh_addr;                /* Address of block tracker created */
+
+    h5_fixname(FILENAME[0], fapl, filename, sizeof filename);
+
+    /* Create the file to work on */
+    if ((file=H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl))<0) TEST_ERROR;
+	
+    /* Get a pointer to the internal file object */
+    if (NULL==(f=H5I_object(file))) {
+	H5Eprint_stack(H5E_DEFAULT, stdout);
+	TEST_ERROR;
+    } /* end if */
+
+    /*
+     * Test segmented heap creation
+     */
+    TESTING("segmented heap creation");
+    if (H5SH_create(f, H5P_DATASET_XFER_DEFAULT, &sh_addr/*out*/, SHEAP_TYPE, (hsize_t)SHEAP_MIN_SIZE, (hsize_t)SHEAP_MAX_EXPAND_SIZE)<0) {
+	H5_FAILED();
+	H5Eprint_stack(H5E_DEFAULT, stdout);
+	goto error;
+    } /* end if */
+
+    PASSED();
+
+    if (H5Fclose(file)<0) TEST_ERROR;
+
+    return 0;
+
+error:
+    H5E_BEGIN_TRY {
+	H5Fclose(file);
+    } H5E_END_TRY;
+    return 1;
+} /* test_create() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	test_allocate_simple
+ *
+ * Purpose:	Basic tests for the segmented heap code
+ *
+ * Return:	Success:	0
+ *
+ *		Failure:	1
+ *
+ * Programmer:	Quincey Koziol
+ *              Thursday, March 24, 2005
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+static int
+test_allocate_simple(hid_t fapl)
+{
+    hid_t	file=-1;
+    char	filename[1024];
+    H5F_t	*f=NULL;
+    haddr_t     sh_addr;                /* Address of block tracker created */
+    haddr_t     obj_addr;               /* Address for object */
+    hsize_t     obj_len;                /* Length of object */
+
+    h5_fixname(FILENAME[0], fapl, filename, sizeof filename);
+
+    /* Create the file to work on */
+    if ((file=H5Fcreate(filename, H5F_ACC_TRUNC, H5P_DEFAULT, fapl))<0) TEST_ERROR;
+	
+    /* Get a pointer to the internal file object */
+    if (NULL==(f=H5I_object(file))) {
+	H5Eprint_stack(H5E_DEFAULT, stdout);
+	TEST_ERROR;
+    } /* end if */
+
+    /* Create segmented heap */
+    if (H5SH_create(f, H5P_DATASET_XFER_DEFAULT, &sh_addr/*out*/, SHEAP_TYPE, (hsize_t)SHEAP_MIN_SIZE, (hsize_t)SHEAP_MAX_EXPAND_SIZE)<0) {
+	H5_FAILED();
+	H5Eprint_stack(H5E_DEFAULT, stdout);
+	goto error;
+    } /* end if */
+
+    /*
+     * Test segmented heap allocation
+     */
+    TESTING("segmented heap allocate first block");
+
+    /* Allocate space for a simple object */
+    obj_len = 10;
+    if (H5SH_alloc(f, H5P_DATASET_XFER_DEFAULT, sh_addr, obj_len, &obj_addr/*out*/)<0) {
+	H5_FAILED();
+	H5Eprint_stack(H5E_DEFAULT, stdout);
+	goto error;
+    } /* end if */
+    if(obj_addr != 1178) TEST_ERROR;
+
+    PASSED();
+
+    TESTING("segmented heap allocate into free space");
+
+    /* Allocate space for a simple object */
+    obj_len = 3800;
+    if (H5SH_alloc(f, H5P_DATASET_XFER_DEFAULT, sh_addr, obj_len, &obj_addr/*out*/)<0) {
+	H5_FAILED();
+	H5Eprint_stack(H5E_DEFAULT, stdout);
+	goto error;
+    } /* end if */
+    if(obj_addr != 1188) TEST_ERROR;
+
+    PASSED();
+
+    TESTING("segmented heap allocate another heap block");
+
+    /* Allocate space for a simple object */
+    obj_len = 512;
+    if (H5SH_alloc(f, H5P_DATASET_XFER_DEFAULT, sh_addr, obj_len, &obj_addr/*out*/)<0) {
+	H5_FAILED();
+	H5Eprint_stack(H5E_DEFAULT, stdout);
+	goto error;
+    } /* end if */
+    if(obj_addr != 6298) TEST_ERROR;
+
+    PASSED();
+
+    TESTING("segmented heap extend heap block");
+
+    /* Allocate space for a simple object */
+    obj_len = 4096;
+    if (H5SH_alloc(f, H5P_DATASET_XFER_DEFAULT, sh_addr, obj_len, &obj_addr/*out*/)<0) {
+	H5_FAILED();
+	H5Eprint_stack(H5E_DEFAULT, stdout);
+	goto error;
+    } /* end if */
+    if(obj_addr != 6810) TEST_ERROR;
+
+    PASSED();
+
+    if (H5Fclose(file)<0) TEST_ERROR;
+
+    return 0;
+
+error:
+    H5E_BEGIN_TRY {
+	H5Fclose(file);
+    } H5E_END_TRY;
+    return 1;
+} /* test_allocate_simple() */
+
+
+/*-------------------------------------------------------------------------
+ * Function:	main
+ *
+ * Purpose:	Test the segmented heap code
+ *
+ * Return:	Success:	
+ *
+ *		Failure:	
+ *
+ * Programmer:	Quincey Koziol
+ *              Wednesday, March 23, 2005
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+int
+main(void)
+{
+    hid_t	fapl=-1;
+    int		nerrors=0;
+
+    /* Reset library */
+    h5_reset();
+    fapl = h5_fileaccess();
+
+    /* Test segmented heap creation */
+    nerrors += test_create(fapl);
+
+    /* Test segmented heap allocation */
+    nerrors += test_allocate_simple(fapl);
+
+    if (nerrors) goto error;
+    puts("All segmented heap tests passed.");
+#ifndef QAK
+    h5_cleanup(FILENAME, fapl);
+#else /* QAK */
+HDfprintf(stderr,"Uncomment cleanup!\n");
+#endif /* QAK */
+    return 0;
+
+error:
+    puts("*** TESTS FAILED ***");
+    H5E_BEGIN_TRY {
+	H5Pclose(fapl);
+    } H5E_END_TRY;
+    return 1;
+}
+
diff --git a/tools/misc/h5debug.c b/tools/misc/h5debug.c
index dca6216..cc2aa3a 100644
--- a/tools/misc/h5debug.c
+++ b/tools/misc/h5debug.c
@@ -29,6 +29,7 @@
 #define H5B2_PACKAGE		/*suppress error about including H5B2pkg  */
 #define H5B2_TESTING		/*suppress warning about H5B2 testing funcs*/
 #define H5BT_PACKAGE		/*suppress error about including H5BTpkg  */
+#define H5SH_PACKAGE		/*suppress error about including H5SHpkg  */
 
 #include "H5private.h"		/* Generic Functions			*/
 #include "H5Bprivate.h"
@@ -42,6 +43,7 @@
 #include "H5Iprivate.h"
 #include "H5Opkg.h"
 #include "H5Pprivate.h"
+#include "H5SHpkg.h"		/* Segmented heap			*/
 
 /* File drivers */
 #include "H5FDfamily.h"
@@ -253,6 +255,12 @@ main(int argc, char *argv[])
          */
         status = H5BT_hdr_debug(f, H5P_DATASET_XFER_DEFAULT, addr, stdout, 0, VCOL);
 
+    } else if (!HDmemcmp(sig, H5SH_MAGIC, H5SH_SIZEOF_MAGIC)) {
+        /*
+         * Debug a segmented heap info
+         */
+        status = H5SH_debug(f, H5P_DATASET_XFER_DEFAULT, addr, stdout, 0, VCOL);
+
     } else if (sig[0] == H5O_VERSION) {
         /*
          * This could be an object header.  Since they don't have a signature