[svn-r12] ./src/H5AC.c

	Fails sooner if the type of object requested doesn't match
	the type of object cached.

./src/H5B.c
./src/H5Bprivate.h
./src/H5Fprivate.h
./src/H5G.c
./src/H5Gnode.c
./src/H5Gprivate.h
./src/H5H.c
./src/H5Hprivate.h
	Changed lots of `H5*_HDR_SIZE' macros to `H5*_SIZEOF_HDR' to make
	things more consistent.

	Added H5*_SIZEOF_MAGIC macros.

	Added debugging functions to some of the packages.

./src/H5F.c
	Fixed a bug with reading past the end of a buffer.

./src/H5Tproto.h
	Added prototypes for H5Tadd_field() and H5Tget_fields().

./src/debug.c
	Low-level file debugging program.

./src/Makefile
	Builds `debug' as one of the main targets.  The target is
	called `debug_hdf5' so it doesn't conflict with the `debug'
	target that was already there.  But the executable is called
	`debug'.

13 files changed, 609 insertions, 51 deletions

diff --git a/src/H5AC.c b/src/H5AC.c
index cca36bc..140a52d 100644
--- a/src/H5AC.c
+++ b/src/H5AC.c
@@ -96,6 +96,12 @@ H5AC_dest (hdf5_file_t *f)
  *
  * Modifications:
  *
+ * 	Robb Matzke, 4 Aug 1997
+ *	Fails immediately if the cached object is at the correct address
+ *	but is of the wrong type.  This happens if the caller doesn't know
+ *	what type of object is at the address and calls this function with
+ *	various type identifiers until one succeeds (cf., the debugger).
+ *
  *-------------------------------------------------------------------------
  */
 void *
@@ -119,6 +125,15 @@ H5AC_find (hdf5_file_t *f, const H5AC_class_t *type, haddr_t addr,
    }
 
    /*
+    * Fail if the item in the cache is at the correct address but is
+    * of the wrong type.
+    */
+   if (f->cache[idx].type && f->cache[idx].addr==addr &&
+       f->cache[idx].type!=type) {
+      return NULL;
+   }
+
+   /*
     * Load a new thing.  If it can't be loaded, then return an error
     * without preempting anything.
     */
diff --git a/src/H5B.c b/src/H5B.c
index fadc6f5..89316b2 100644
--- a/src/H5B.c
+++ b/src/H5B.c
@@ -181,7 +181,7 @@ H5B_new (hdf5_file_t *f, const H5B_class_t *type, size_t sizeof_rkey)
     * `page' buffer.  Each native key pointer should be null until the key is
     * translated to native format.
     */
-   for (i=0,offset=H5B_HDR_SIZE(f);
+   for (i=0,offset=H5B_SIZEOF_HDR(f);
 	i<2*type->k;
 	i++,offset+=bt->sizeof_rkey+H5F_SIZEOF_OFFSET(f)) {
 
@@ -249,7 +249,7 @@ H5B_load (hdf5_file_t *f, haddr_t addr, const void *_data)
    p = bt->page;
 
    /* magic number */
-   if (memcmp (p, H5B_MAGIC, 4)) goto error;
+   if (memcmp (p, H5B_MAGIC, H5B_SIZEOF_MAGIC)) goto error;
    p += 4;
 
    /* node type and level */
@@ -326,7 +326,7 @@ H5B_flush (hdf5_file_t *f, hbool_t destroy, haddr_t addr, H5B_t *bt)
    if (bt->dirty) {
       
       /* magic number */
-      memcpy (p, H5B_MAGIC, 4);
+      memcpy (p, H5B_MAGIC, H5B_SIZEOF_MAGIC);
       p += 4;
 
       /* node type and level */
@@ -513,14 +513,14 @@ H5B_split (hdf5_file_t *f, const H5B_class_t *type, haddr_t addr, intn anchor)
    /*
     * Copy data into the new node from the old node.
     */
-   memcpy (bt->page + H5B_HDR_SIZE(f),
-	   old->page + H5B_HDR_SIZE(f) + delta*recsize,
+   memcpy (bt->page + H5B_SIZEOF_HDR(f),
+	   old->page + H5B_SIZEOF_HDR(f) + delta*recsize,
 	   type->k * recsize);
    memcpy (bt->native,
 	   old->native + delta * type->sizeof_nkey,
 	   (type->k+1) * type->sizeof_nkey);
 
-   for (i=0,offset=H5B_HDR_SIZE(f); i<=2*type->k; i++,offset+=recsize) {
+   for (i=0,offset=H5B_SIZEOF_HDR(f); i<=2*type->k; i++,offset+=recsize) {
 
       /* key */
       if (i<=type->k) {
@@ -555,8 +555,8 @@ H5B_split (hdf5_file_t *f, const H5B_class_t *type, haddr_t addr, intn anchor)
    old->nchildren = type->k;
    
    if (H5B_ANCHOR_RT==anchor) {
-      memcpy (old->page + H5B_HDR_SIZE(f),
-	      old->page + H5B_HDR_SIZE(f) + delta*recsize,
+      memcpy (old->page + H5B_SIZEOF_HDR(f),
+	      old->page + H5B_SIZEOF_HDR(f) + delta*recsize,
 	      type->k * recsize);
       memmove (old->native,
 	       old->native + delta * type->sizeof_nkey,
@@ -803,8 +803,8 @@ H5B_insert_child (hdf5_file_t *f, const H5B_class_t *type, haddr_t addr,
       /*
        * The MD_KEY is the left key of the new node.
        */
-      memmove (bt->page + H5B_HDR_SIZE(f) + (idx+1)*recsize,
-	       bt->page + H5B_HDR_SIZE(f) + idx*recsize,
+      memmove (bt->page + H5B_SIZEOF_HDR(f) + (idx+1)*recsize,
+	       bt->page + H5B_SIZEOF_HDR(f) + idx*recsize,
 	       (bt->nchildren-idx)*recsize + bt->sizeof_rkey);
 
       memmove (bt->native + (idx+1) * type->sizeof_nkey,
@@ -822,9 +822,9 @@ H5B_insert_child (hdf5_file_t *f, const H5B_class_t *type, haddr_t addr,
       /*
        * The MD_KEY is the right key of the new node.
        */
-      memmove (bt->page + (H5B_HDR_SIZE(f) +
+      memmove (bt->page + (H5B_SIZEOF_HDR(f) +
 			   (idx+1)*recsize + bt->sizeof_rkey),
-	       bt->page + (H5B_HDR_SIZE(f) +
+	       bt->page + (H5B_SIZEOF_HDR(f) +
 			   idx*recsize + bt->sizeof_rkey),
 	       (bt->nchildren-idx) * recsize);
 
@@ -1170,8 +1170,60 @@ H5B_nodesize (hdf5_file_t *f, const H5B_class_t *type,
       *total_nkey_size = (2 * type->k + 1) * type->sizeof_nkey;
    }
 
-   return (H5B_HDR_SIZE(f) +				/*node header	*/
+   return (H5B_SIZEOF_HDR(f) +				/*node header	*/
 	   2 * type->k * H5F_SIZEOF_OFFSET(f) +		/*child pointers*/
 	   (2*type->k+1) * sizeof_rkey);		/*keys		*/
 }
 
+
+/*-------------------------------------------------------------------------
+ * Function:	H5B_debug
+ *
+ * Purpose:	Prints debugging info about a B-tree.
+ *
+ * Return:	Success:	0
+ *
+ *		Failure:	-1
+ *
+ * Programmer:	Robb Matzke
+ *		robb@maya.nuance.com
+ *		Aug  4 1997
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5B_debug (hdf5_file_t *f, haddr_t addr, FILE *stream, intn indent,
+	   intn fwidth, const H5B_class_t *type)
+{
+   H5B_t		*bt = H5AC_find (f, H5AC_BT, addr, type);
+
+   if (!bt) return -1;
+
+   fprintf (stream, "%*s%-*s %d\n", indent, "", fwidth,
+	    "Tree type ID:",
+	    (int)(bt->type->id));
+   fprintf (stream, "%*s%-*s %lu\n", indent, "", fwidth,
+	    "Size of raw (disk) key:",
+	    (unsigned long)(bt->sizeof_rkey));
+   fprintf (stream, "%*s%-*s %d\n", indent, "", fwidth,
+	    "Dirty flag:",
+	    (int)(bt->dirty));
+   fprintf (stream, "%*s%-*s %d\n", indent, "", fwidth,
+	    "Number of initial dirty children:",
+	    (int)(bt->ndirty));
+   fprintf (stream, "%*s%-*s %d\n", indent, "", fwidth,
+	    "Level:",
+	    (int)(bt->level));
+   fprintf (stream, "%*s%-*s %lu\n", indent, "", fwidth,
+	    "Address of left sibling:",
+	    (unsigned long)(bt->left));
+   fprintf (stream, "%*s%-*s %lu\n", indent, "", fwidth,
+	    "Address of right sibling:",
+	    (unsigned long)(bt->right));
+   fprintf (stream, "%*s%-*s %d\n", indent, "", fwidth,
+	    "Number of children:",
+	    (int)(bt->nchildren));
+   return 0;
+}
diff --git a/src/H5Bprivate.h b/src/H5Bprivate.h
index 3a029e4..bb9d95c 100644
--- a/src/H5Bprivate.h
+++ b/src/H5Bprivate.h
@@ -21,11 +21,20 @@
 
 #include "H5Fprivate.h"
 
-#define H5B_MAGIC	"TREE"	/* tree node magic number		*/
-#define H5B_HDR_SIZE(F)	(8+2*H5F_SIZEOF_OFFSET(F))
+#define H5B_MAGIC	"TREE"	/*tree node magic number		*/
+#define H5B_SIZEOF_MAGIC 4	/*size of magic number			*/
+
+#define H5B_SIZEOF_HDR(F)						      \
+   (H5B_SIZEOF_MAGIC +		/*magic number				*/    \
+    4 +				/*type, level, num entries		*/    \
+    2*H5F_SIZEOF_OFFSET(F))	/*left and right sibling addresses	*/
 
 #define H5B_ANCHOR_LT	0	/* left node is anchored, right is new	*/
 #define H5B_ANCHOR_RT	1	/* right node is anchored, left is new	*/
+
+typedef enum H5B_subid_t {
+   H5B_SUBTYPE_SNODE	=0	/*B-tree is for symbol table nodes	*/
+} H5B_subid_t;
    
 
 /*
@@ -33,7 +42,7 @@
  * variable of this type that contains class variables and methods.
  */
 typedef struct H5B_class_t {
-   intn		id;		/*id as found in file			*/
+   H5B_subid_t	id;		/*id as found in file			*/
    intn		k;		/* max children is 2k			*/
    size_t	sizeof_nkey;	/*size of native (memory) key		*/
    size_t	(*get_sizeof_rkey)(hdf5_file_t*);
@@ -75,7 +84,8 @@ typedef struct H5B_t {
 /*
  * Library prototypes.
  */
-herr_t H5B_debug (hdf5_file_t *f, haddr_t addr, const H5B_class_t *type);
+herr_t H5B_debug (hdf5_file_t *f, haddr_t addr, FILE *stream, intn indent,
+		  intn fwidth, const H5B_class_t *type);
 haddr_t H5B_new (hdf5_file_t *f, const H5B_class_t *type, size_t sizeof_rkey);
 herr_t H5B_find (hdf5_file_t *f, const H5B_class_t *type, haddr_t addr,
 		 void *udata);
diff --git a/src/H5F.c b/src/H5F.c
index 7a43ca9..8e37967 100644
--- a/src/H5F.c
+++ b/src/H5F.c
@@ -584,6 +584,7 @@ hatom_t H5Fopen(const char *filename, uintn flags, hatom_t access_temp)
     haddr_t curr_off=0;          /* The current offset to check in the file */
     size_t file_len=0;          /* The length of the file we are checking */
     hatom_t ret_value = FAIL;
+    size_t	variable_size;	/*size of the variable part of the bb */
 
     FUNC_ENTER(H5F_mask, ID_H5Fopen, H5F_init_interface, FAIL);
 
@@ -670,9 +671,9 @@ hatom_t H5Fopen(const char *filename, uintn flags, hatom_t access_temp)
     
     /* Read in the fixed-size part of the boot-block */
     if(H5F_READ(new_file->file_handle,temp_buf,16)==FAIL)
-        HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL);
+        HGOTO_ERROR(H5E_IO, H5E_READERROR, FAIL);
 
-    /* Decode the boot block */
+    /* Decode fixed-size part of the boot block */
     p=temp_buf;
     new_file->file_create_parms.bootblock_ver=*p++;    /* Decode Boot-block version # */
     new_file->file_create_parms.smallobject_ver=*p++;  /* Decode Small-Object Heap version # */
@@ -684,6 +685,17 @@ hatom_t H5Fopen(const char *filename, uintn flags, hatom_t access_temp)
     p++;                         /* Decode the reserved byte :-) */
     UINT32DECODE(p,new_file->file_create_parms.btree_page_size);    /* Decode the B-Tree page size */
     UINT32DECODE(p,new_file->consist_flags);       /* Decode File-Consistancy flags */
+
+    /* Read the variable-size part of the boot-block */
+    variable_size = H5F_SIZEOF_OFFSET(new_file) +	/*offset of global small-object heap*/
+		    H5F_SIZEOF_OFFSET(new_file) +	/*offset of global free list*/
+		    H5F_SIZEOF_SIZE(new_file) +		/*logical size of HDF5 file*/
+		    H5G_SIZEOF_ENTRY(new_file);		/*root symbol table entry*/
+    if (H5F_READ(new_file->file_handle, temp_buf, variable_size)<0)
+       HGOTO_ERROR (H5E_IO, H5E_READERROR, FAIL);
+
+    /* Decode the variable-size part of the boot block */
+    p = temp_buf;
     H5F_decode_offset(new_file,p,new_file->smallobj_off);  /* Decode offset of global small-object heap */
     H5F_decode_offset(new_file,p,new_file->freespace_off);  /* Decode offset of global free-space heap */
     H5F_decode_length(new_file,p,new_file->logical_len); /* Decode logical length of file */
@@ -846,3 +858,85 @@ H5F_block_write (hdf5_file_t *f, haddr_t addr, size_t size, void *buf)
     PABLO_TRACE_OFF(H5F_mask, ID_H5F_block_write);
     return SUCCEED;
 }
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5F_debug
+ *
+ * Purpose:	Prints a file header to the specified stream.  Each line
+ *		is indented and the field name occupies the specified width
+ *		number of characters.
+ *
+ * Return:	Success:	0
+ *
+ *		Failure:	-1
+ *
+ * Programmer:	Robb Matzke
+ *		robb@maya.nuance.com
+ *		Aug  1 1997
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5F_debug (hdf5_file_t *f, haddr_t addr, FILE *stream, intn indent,
+	   intn fwidth)
+{
+   fprintf (stream, "%*sFile Boot Block...\n", indent, "");
+   
+   fprintf (stream, "%*s%-*s %s\n", indent, "", fwidth,
+	    "Directory:",
+	    f->dir);
+   fprintf (stream, "%*s%-*s %s\n", indent, "", fwidth,
+	    "File name:",
+	    f->filename);
+   fprintf (stream, "%*s%-*s 0x%08x\n", indent, "", fwidth,
+	    "Permissions",
+	    (unsigned)(f->acc_perm));
+   fprintf (stream, "%*s%-*s %u\n", indent, "", fwidth,
+	    "Reference count:",
+	    (unsigned)(f->ref_count));
+   fprintf (stream, "%*s%-*s 0x%08lx\n", indent, "", fwidth,
+	    "Consistency flags:",
+	    (unsigned long)(f->consist_flags));
+   fprintf (stream, "%*s%-*s %ld\n", indent, "", fwidth,
+	    "Small object heap address:",
+	    (long)(f->smallobj_off));
+   fprintf (stream, "%*s%-*s %ld\n", indent, "", fwidth,
+	    "Free list address:",
+	    (long)(f->freespace_off));
+   fprintf (stream, "%*s%-*s %lu\n", indent, "", fwidth,
+	    "Logical file length:",
+	    (unsigned long)(f->logical_len));
+   fprintf (stream, "%*s%-*s %lu\n", indent, "", fwidth,
+	    "Size of user block:",
+	    (unsigned long)(f->file_create_parms.userblock_size));
+   fprintf (stream, "%*s%-*s %u\n", indent, "", fwidth,
+	    "Size of file size_t type:",
+	    (unsigned)(f->file_create_parms.offset_size));
+   fprintf (stream, "%*s%-*s %u\n", indent, "", fwidth,
+	    "Size of file off_t type:",
+	    (unsigned)(f->file_create_parms.length_size));
+   fprintf (stream, "%*s%-*s %u\n", indent, "", fwidth,
+	    "Bytes per B-tree page:",
+	    (unsigned)(f->file_create_parms.btree_page_size));
+   fprintf (stream, "%*s%-*s %u\n", indent, "", fwidth,
+	    "Boot block version number:",
+	    (unsigned)(f->file_create_parms.bootblock_ver));
+   fprintf (stream, "%*s%-*s %u\n", indent, "", fwidth,
+	    "Small object heap version number:",
+	    (unsigned)(f->file_create_parms.smallobject_ver));
+   fprintf (stream, "%*s%-*s %u\n", indent, "", fwidth,
+	    "Free list version number:",
+	    (unsigned)(f->file_create_parms.freespace_ver));
+   fprintf (stream, "%*s%-*s %u\n", indent, "", fwidth,
+	    "Object directory version number:",
+	    (unsigned)(f->file_create_parms.objectdir_ver));
+   fprintf (stream, "%*s%-*s %u\n", indent, "", fwidth,
+	    "Shared header version number:",
+	    (unsigned)(f->file_create_parms.sharedheader_ver));
+	    
+
+   return 0;
+}
diff --git a/src/H5Fprivate.h b/src/H5Fprivate.h
index 2856b6a..fde8fb3 100644
--- a/src/H5Fprivate.h
+++ b/src/H5Fprivate.h
@@ -92,6 +92,8 @@ void H5F_encode_offset_unusual(const hdf5_file_t *f, uint8 **p, uint8 *o);
 intn H5F_compare_filename(const VOIDP obj, const VOIDP key);
 herr_t H5F_block_read (hdf5_file_t *f, haddr_t addr, size_t size, void *buf);
 herr_t H5F_block_write (hdf5_file_t *f, haddr_t addr, size_t size, void *buf);
+herr_t H5F_debug (hdf5_file_t *f, haddr_t addr, FILE *stream, intn indent,
+		  intn fwidth);
 
 #endif /* HDF5FILE_H */
 
diff --git a/src/H5G.c b/src/H5G.c
index 3c1f21a..fa7da12 100644
--- a/src/H5G.c
+++ b/src/H5G.c
@@ -347,7 +347,7 @@ H5G_decode (hdf5_file_t *f, uint8 **pp, H5G_entry_t *ent)
       abort();
    }
 
-   *pp = p_ret + 2*H5F_SIZEOF_OFFSET(f) + 4 + 24;
+   *pp = p_ret + H5G_SIZEOF_ENTRY(f);
    return 0;
 }
 
@@ -433,7 +433,7 @@ H5G_encode (hdf5_file_t *f, uint8 **pp, H5G_entry_t *ent)
       abort();
    }
 
-   *pp = p_ret + 2*H5F_SIZEOF_OFFSET(f) + 4 + 24;
+   *pp = p_ret + H5G_SIZEOF_ENTRY(f);
    return 0;
 }
 
diff --git a/src/H5Gnode.c b/src/H5Gnode.c
index 52638eb..3ce046e 100644
--- a/src/H5Gnode.c
+++ b/src/H5Gnode.c
@@ -60,7 +60,7 @@ static const H5AC_class_t H5AC_SNODE[1] = {{
 
 /* H5G inherits B-tree like properties from H5B */
 const H5B_class_t H5B_SNODE[1] = {{
-   0,						/*id			*/
+   H5B_SUBTYPE_SNODE,				/*id			*/
    64,						/*k			*/
    sizeof (H5G_node_key_t),			/*sizeof_nkey		*/
    H5G_node_sizeof_rkey,			/*get_sizeof_rkey	*/
@@ -167,7 +167,8 @@ H5G_node_encode_key (hdf5_file_t *f, uint8 *raw, void *_key)
 static size_t
 H5G_node_size (hdf5_file_t *f)
 {
-   return H5G_HDR_SIZE(f) + (2*H5G_NODE_K) * (2*H5F_SIZEOF_OFFSET(f));
+   return H5G_NODE_SIZEOF_HDR(f) +
+      (2*H5G_NODE_K) * H5G_SIZEOF_ENTRY(f);
 }
 
 
@@ -244,7 +245,7 @@ H5G_node_flush (hdf5_file_t *f, hbool_t destroy, haddr_t addr, H5G_node_t *sym)
       buf = p = H5MM_xmalloc (size);
 
       /* magic number */
-      HDmemcpy (p, H5G_NODE_MAGIC, 4);
+      HDmemcpy (p, H5G_NODE_MAGIC, H5G_NODE_SIZEOF_MAGIC);
       p += 4;
 
       /* version number */
@@ -303,7 +304,7 @@ H5G_node_load (hdf5_file_t *f, haddr_t addr, const void *_udata)
    H5F_block_read (f, addr, size, buf);
 
    /* magic */
-   if (HDmemcmp (p, H5G_NODE_MAGIC, 4)) goto error;
+   if (HDmemcmp (p, H5G_NODE_MAGIC, H5G_NODE_SIZEOF_MAGIC)) goto error;
    p += 4;
 
    /* version */
@@ -693,3 +694,100 @@ H5G_node_list (hdf5_file_t *f, haddr_t addr, void *_udata)
    return 0;
 }
 
+
+/*-------------------------------------------------------------------------
+ * Function:	H5G_node_debug
+ *
+ * Purpose:	Prints debugging information about a symbol table node
+ *		or a B-tree node for a symbol table B-tree.
+ *
+ * Return:	Success:	0
+ *
+ *		Failure:	-1
+ *
+ * Programmer:	Robb Matzke
+ *		robb@maya.nuance.com
+ *		Aug  4 1997
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5G_node_debug (hdf5_file_t *f, haddr_t addr, FILE *stream, intn indent,
+		intn fwidth)
+{
+   int		i, j;
+   char		buf[64];
+   H5G_node_t	*sn = H5AC_find (f, H5AC_SNODE, addr, NULL);
+
+   /*
+    * If we couldn't load the symbol table node, then try loading the
+    * B-tree node.
+    */
+   if (!sn) {
+      return H5B_debug (f, addr, stream, indent, fwidth, H5B_SNODE);
+   }
+
+
+   if (!sn) return -1;
+   fprintf (stream, "%*sSymbol Table Node...\n", indent, "");
+   fprintf (stream, "%*s%-*s %d\n", indent, "", fwidth,
+	    "Dirty:",
+	    sn->dirty);
+   fprintf (stream, "%*s%-*s %d of %d\n", indent, "", fwidth,
+	    "Number of Symbols:",
+	    sn->nsyms, 2*H5G_NODE_K);
+
+   indent += 3;
+   fwidth = MAX (0, fwidth-3);
+   for (i=0; i<sn->nsyms; i++) {
+      fprintf (stream, "%*sSymbol %d:\n", indent-3, "", i);
+      fprintf (stream, "%*s%-*s %lu\n", indent, "", fwidth,
+	       "Name offset into private heap:",
+	       (unsigned long)(sn->entry[i].name_off));
+      fprintf (stream, "%*s%-*s %lu\n", indent, "", fwidth,
+	       "Object header address:",
+	       (unsigned long)(sn->entry[i].header));
+      
+      fprintf (stream, "%*s%-*s ", indent, "", fwidth,
+	       "Symbol type:");
+      switch (sn->entry[i].type) {
+      case H5G_NOTHING_CACHED:
+	 fprintf (stream, "Nothing Cached\n");
+	 break;
+	 
+      case H5G_CACHED_SDATA:
+	 fprintf (stream, "S-data\n");
+	 fprintf (stream, "%*s%-*s %u\n", indent, "", fwidth,
+		  "Number type:",
+		  (unsigned)(sn->entry[i].cache.sdata.nt));
+	 fprintf (stream, "%*s%-*s %u\n", indent, "", fwidth,
+		  "Dimensionality:",
+		  (unsigned)(sn->entry[i].cache.sdata.ndim));
+	 for (j=0; j<sn->entry[i].cache.sdata.ndim && j<4; j++) {
+	    sprintf (buf, "Dimension %d", j);
+	    fprintf (stream, "%*s%-*s %u\n", indent, "", fwidth,
+		     buf,
+		     (unsigned)(sn->entry[i].cache.sdata.dim[j]));
+	 }
+	 break;
+	 
+      case H5G_CACHED_SYMTAB:
+	 fprintf (stream, "Symbol Table\n");
+	 fprintf (stream, "%*s%-*s %lu\n", indent, "", fwidth,
+		  "B-tree address:",
+		  (unsigned long)(sn->entry[i].cache.symtab.btree));
+	 fprintf (stream, "%*s%-*s %lu\n", indent, "", fwidth,
+		  "Heap address:",
+		  (unsigned long)(sn->entry[i].cache.symtab.heap));
+	 break;
+
+      default:
+	 fprintf (stream, "*** Unknown symbol type %d\n", sn->entry[i].type);
+	 break;
+      }
+   }
+   return 0;
+}
+   
diff --git a/src/H5Gprivate.h b/src/H5Gprivate.h
index 73a06ee..5e08c4d 100644
--- a/src/H5Gprivate.h
+++ b/src/H5Gprivate.h
@@ -25,9 +25,16 @@
 #include "H5Fprivate.h"
 
 #define H5G_NODE_MAGIC	"SNOD"	/*symbol table node magic number	*/
+#define H5G_NODE_SIZEOF_MAGIC 4 /*sizeof symbol node magic number	*/
 #define H5G_NODE_VERS	1	/*symbol table node version number	*/
 #define H5G_NODE_K	64	/*min degree.  max degree is twice this	*/
-#define H5G_HDR_SIZE(F)	8
+#define H5G_NODE_SIZEOF_HDR(F) (H5G_NODE_SIZEOF_MAGIC + 4)
+#define H5G_SIZEOF_ENTRY(F)						      \
+   (H5F_SIZEOF_OFFSET(F) +	/*offset of name into heap     		*/    \
+    H5F_SIZEOF_OFFSET(F) +	/*address of object header		*/    \
+    4 +				/*entry type				*/    \
+    24)				/*scratch pad space			*/
+    
 
 /*
  * Various types of object header information can be cached in a symbol
@@ -126,6 +133,8 @@ extern const H5B_class_t H5B_SNODE[1];
 /*
  * Library prototypes...
  */
+herr_t H5G_node_debug (hdf5_file_t *f, haddr_t addr, FILE *stream, intn indent,
+		       intn fwidth);
 haddr_t H5G_new (hdf5_file_t *f, size_t init);
 haddr_t H5G_find (hdf5_file_t *f, haddr_t addr, const char *name,
 		  H5G_entry_t *entry);
diff --git a/src/H5H.c b/src/H5H.c
index 9805bbd..11ed3b2 100644
--- a/src/H5H.c
+++ b/src/H5H.c
@@ -22,10 +22,17 @@
 #include "H5MFprivate.h"		/*file memory management	*/
 #include "H5MMprivate.h"		/*core memory management	*/
 
-#define H5H_MAGIC	"HEAP"		/*heap magic number		*/
 #define H5H_FREE_NULL	1		/*end of free list on disk	*/
-#define H5H_HDR_SIZE(F)	(4+H5F_SIZEOF_SIZE(F)+2*H5F_SIZEOF_OFFSET(F))
-#define H5H_SIZEOF_FREE(F) (H5F_SIZEOF_SIZE(F)+H5F_SIZEOF_OFFSET(F))
+
+#define H5H_SIZEOF_HDR(F)						      \
+   (H5H_SIZEOF_MAGIC +			/*heap signature		*/    \
+    H5F_SIZEOF_SIZE (F) +		/*data size			*/    \
+    H5F_SIZEOF_OFFSET (F) +		/*free list head		*/    \
+    H5F_SIZEOF_OFFSET (F))		/*data address			*/
+   
+#define H5H_SIZEOF_FREE(F)						      \
+   (H5F_SIZEOF_OFFSET (F) +		/*ptr to next free block	*/    \
+   H5F_SIZEOF_SIZE (F))			/*size of this free block	*/
 
 typedef struct H5H_free_t {
    off_t	offset;			/*offset of free block		*/
@@ -92,15 +99,15 @@ H5H_new (hdf5_file_t *f, size_t size_hint)
    }
 
    /* allocate file version */
-   total_size = H5H_HDR_SIZE(f) + size_hint;
+   total_size = H5H_SIZEOF_HDR(f) + size_hint;
    if ((addr = H5MF_alloc (f, total_size))<0) return -1;
 
    /* allocate memory version */
    heap = H5MM_xcalloc (1, sizeof(H5H_t));
-   heap->addr = addr + H5H_HDR_SIZE(f);
+   heap->addr = addr + H5H_SIZEOF_HDR(f);
    heap->disk_alloc = size_hint;
    heap->mem_alloc = size_hint;
-   heap->chunk = H5MM_xmalloc (H5H_HDR_SIZE(f) + size_hint);
+   heap->chunk = H5MM_xmalloc (H5H_SIZEOF_HDR(f) + size_hint);
 
    /* free list */
    if (size_hint) {
@@ -146,15 +153,15 @@ H5H_load (hdf5_file_t *f, haddr_t addr, const void *udata)
    haddr_t	free_block;
 
    assert (addr>0);
-   assert (H5H_HDR_SIZE(f) <= sizeof hdr);
+   assert (H5H_SIZEOF_HDR(f) <= sizeof hdr);
    assert (!udata);
 
-   if (H5F_block_read (f, addr, H5H_HDR_SIZE(f), hdr)<0) goto error;
+   if (H5F_block_read (f, addr, H5H_SIZEOF_HDR(f), hdr)<0) goto error;
    p = hdr;
 
    /* magic number */
-   if (HDmemcmp (hdr, H5H_MAGIC, 4)) goto error;
-   p += 4;
+   if (HDmemcmp (hdr, H5H_MAGIC, H5H_SIZEOF_MAGIC)) goto error;
+   p += H5H_SIZEOF_MAGIC;
 
    /* heap data size */
    H5F_decode_length (f, p, heap->disk_alloc);
@@ -166,10 +173,10 @@ H5H_load (hdf5_file_t *f, haddr_t addr, const void *udata)
 
    /* data */
    H5F_decode_offset (f, p, heap->addr);
-   heap->chunk = H5MM_xmalloc (H5H_HDR_SIZE(f) + heap->mem_alloc);
+   heap->chunk = H5MM_xmalloc (H5H_SIZEOF_HDR(f) + heap->mem_alloc);
    if (heap->disk_alloc &&
        H5F_block_read (f, heap->addr, heap->disk_alloc,
-		       heap->chunk + H5H_HDR_SIZE(f))<0) {
+		       heap->chunk + H5H_SIZEOF_HDR(f))<0) {
       goto error;
    }
 
@@ -184,7 +191,7 @@ H5H_load (hdf5_file_t *f, haddr_t addr, const void *udata)
       tail = fl;
       if (!heap->freelist) heap->freelist = fl;
 		   
-      p = heap->chunk + H5H_HDR_SIZE(f) + free_block;
+      p = heap->chunk + H5H_SIZEOF_HDR(f) + free_block;
       H5F_decode_offset (f, p, free_block);
       H5F_decode_length (f, p, fl->size);
 
@@ -241,7 +248,7 @@ H5H_flush (hdf5_file_t *f, hbool_t destroy, haddr_t addr, H5H_t *heap)
       /*
        * Write the header.
        */
-      HDmemcpy (p, H5H_MAGIC, 4); p += 4;
+      HDmemcpy (p, H5H_MAGIC, H5H_SIZEOF_MAGIC); p += H5H_SIZEOF_MAGIC;
       H5F_encode_length (f, p, heap->mem_alloc);
       H5F_encode_offset (f, p, fl?fl->offset:-1);
       H5F_encode_offset (f, p, heap->addr);
@@ -250,7 +257,7 @@ H5H_flush (hdf5_file_t *f, hbool_t destroy, haddr_t addr, H5H_t *heap)
        * Write the free list.
        */
       while (fl) {
-	 p = heap->chunk + H5H_HDR_SIZE(f) + fl->offset;
+	 p = heap->chunk + H5H_SIZEOF_HDR(f) + fl->offset;
 	 if (fl->next) {
 	    H5F_encode_offset (f, p, fl->next->offset);
 	 } else {
@@ -263,17 +270,17 @@ H5H_flush (hdf5_file_t *f, hbool_t destroy, haddr_t addr, H5H_t *heap)
       /*
        * Copy buffer to disk.
        */
-      if (heap->addr == addr + H5H_HDR_SIZE(f)) {
-	 if (H5F_block_write (f, addr, H5H_HDR_SIZE(f)+heap->disk_alloc,
+      if (heap->addr == addr + H5H_SIZEOF_HDR(f)) {
+	 if (H5F_block_write (f, addr, H5H_SIZEOF_HDR(f)+heap->disk_alloc,
 			      heap->chunk)<0) {
 	    return -1;
 	 }
       } else {
-	 if (H5F_block_write (f, addr, H5H_HDR_SIZE(f), heap->chunk)<0) {
+	 if (H5F_block_write (f, addr, H5H_SIZEOF_HDR(f), heap->chunk)<0) {
 	    return -1;
 	 }
 	 if (H5F_block_write (f, heap->addr, heap->disk_alloc,
-			      heap->chunk + H5H_HDR_SIZE(f))<0) {
+			      heap->chunk + H5H_SIZEOF_HDR(f))<0) {
 	    return -1;
 	 }
       }
@@ -333,7 +340,7 @@ H5H_read (hdf5_file_t *f, haddr_t addr, off_t offset, size_t size, void *buf)
    assert (offset+size<=heap->mem_alloc);
 
    if (!buf) buf = H5MM_xmalloc (size);
-   HDmemcpy (buf, heap->chunk+H5H_HDR_SIZE(f)+offset, size);
+   HDmemcpy (buf, heap->chunk+H5H_SIZEOF_HDR(f)+offset, size);
    return buf;
 }
 
@@ -374,7 +381,7 @@ H5H_peek (hdf5_file_t *f, haddr_t addr, off_t offset)
    H5H_t	*heap = H5AC_find (f, H5AC_HEAP, addr, NULL);
 
    assert (offset>=0 && offset<heap->mem_alloc);
-   return heap->chunk+H5H_HDR_SIZE(f)+offset;
+   return heap->chunk+H5H_SIZEOF_HDR(f)+offset;
 }
 
 
@@ -502,13 +509,13 @@ H5H_insert (hdf5_file_t *f, haddr_t addr, size_t size, const void *buf)
 	       (unsigned long)(heap->mem_alloc + need_more));
       heap->mem_alloc += need_more;
       heap->chunk = H5MM_xrealloc (heap->chunk,
-				   H5H_HDR_SIZE(f)+heap->mem_alloc);
+				   H5H_SIZEOF_HDR(f)+heap->mem_alloc);
    }
 
    /*
     * Copy the data into the heap
     */
-   HDmemcpy (heap->chunk + H5H_HDR_SIZE(f) + offset, buf, size);
+   HDmemcpy (heap->chunk + H5H_SIZEOF_HDR(f) + offset, buf, size);
    return offset;
 }
    
@@ -547,7 +554,7 @@ H5H_write (hdf5_file_t *f, haddr_t addr, off_t offset, size_t size,
    assert (buf);
 
    heap->dirty += 1;
-   HDmemcpy (heap->chunk+H5H_HDR_SIZE(f)+offset, buf, size);
+   HDmemcpy (heap->chunk+H5H_SIZEOF_HDR(f)+offset, buf, size);
    return 0;
 }
 
@@ -651,3 +658,118 @@ H5H_remove (hdf5_file_t *f, haddr_t addr, off_t offset, size_t size)
 
    return 0;
 }
+
+
+/*-------------------------------------------------------------------------
+ * Function:	H5H_debug
+ *
+ * Purpose:	Prints debugging information about a heap.
+ *
+ * Return:	Success:	0
+ *
+ *		Failure:	-1
+ *
+ * Programmer:	Robb Matzke
+ *		robb@maya.nuance.com
+ *		Aug  1 1997
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+herr_t
+H5H_debug (hdf5_file_t *f, haddr_t addr, FILE *stream, intn indent,
+	   intn fwidth)
+{
+   H5H_t	*h = H5AC_find (f, H5AC_HEAP, addr, NULL);
+   int		i, j, overlap;
+   uint8	c;
+   H5H_free_t	*freelist=NULL;
+   uint8	*marker = NULL;
+   size_t	amount_free = 0;
+
+   if (!h) return -1;
+
+   fprintf (stream, "%*sHeap...\n", indent, "");
+   fprintf (stream, "%*s%-*s %d\n", indent, "", fwidth,
+	    "Dirty:",
+	    (int)(h->dirty));
+   fprintf (stream, "%*s%-*s %lu\n", indent, "", fwidth,
+	    "Data bytes allocated on disk:",
+	    (unsigned long)(h->disk_alloc));
+   fprintf (stream, "%*s%-*s %lu\n", indent, "", fwidth,
+	    "Data bytes allocated in core:",
+	    (unsigned long)(h->mem_alloc));
+
+
+   /*
+    * Traverse the free list and check that all free blocks fall within
+    * the heap and that no two free blocks point to the same region of
+    * the heap.
+    */
+   marker = H5MM_xcalloc (h->mem_alloc, 1);
+   for (freelist=h->freelist; freelist; freelist=freelist->next) {
+      fprintf (stream, "%*s%-*s %8lu, %8lu\n", indent, "", fwidth,
+	       "Free Block (offset,size):",
+	       (unsigned long)(freelist->offset),
+	       (unsigned long)(freelist->size));
+      if (freelist->offset + freelist->size > h->mem_alloc) {
+	 fprintf (stream, "***THAT FREE BLOCK IS OUT OF BOUNDS!\n");
+      } else {
+	 for (i=overlap=0; i<freelist->size; i++) {
+	    if (marker[freelist->offset+i]) overlap++;
+	    marker[freelist->offset+i] = 1;
+	 }
+	 if (overlap) {
+	    fprintf (stream,"***THAT FREE BLOCK OVERLAPPED A PREVIOUS ONE!\n");
+	 } else {
+	    amount_free += freelist->size;
+	 }
+      }
+   }
+
+   if (h->mem_alloc) {
+      fprintf (stream, "%*s%-*s %d\n", indent, "", fwidth,
+	       "Percent of heap used:",
+	       100 * (h->mem_alloc - amount_free) / h->mem_alloc);
+   }
+
+   /*
+    * Print the data in a VMS-style octal dump.
+    */
+   fprintf (stream, "%*sData follows (`__' indicates free region)...\n",
+	    indent, "");
+   for (i=0; i<h->disk_alloc; i+=16) {
+      fprintf (stream, "%*s %8d: ", indent, "", i);
+      for (j=0; j<16; j++) {
+	 if (i+j<h->disk_alloc) {
+	    if (marker[i+j]) {
+	       fprintf (stream, "__ ");
+	    } else {
+	       c = h->chunk[H5H_SIZEOF_HDR(f)+i+j];
+	       fprintf (stream, "%02x ", c);
+	    }
+	 } else {
+	    fprintf (stream, "   ");
+	 }
+	 if (7==j) fputc (' ', stream);
+      }
+
+      for (j=0; j<16; j++) {
+	 if (i+j<h->disk_alloc) {
+	    if (marker[i+j]) {
+	       fputc (' ', stream);
+	    } else {
+	       c = h->chunk[H5H_SIZEOF_HDR(f)+i+j];
+	       if (c>' ' && c<'~') fputc (c, stream);
+	       else fputc ('.', stream);
+	    }
+	 }
+      }
+
+      fputc ('\n', stream);
+   }
+      
+   H5MM_xfree (marker);
+   return 0;
+}
diff --git a/src/H5Hprivate.h b/src/H5Hprivate.h
index f896b4a..0c31df3 100644
--- a/src/H5Hprivate.h
+++ b/src/H5Hprivate.h
@@ -20,6 +20,9 @@
 #include "H5Hproto.h"
 #include "H5Fprivate.h"
 
+#define H5H_MAGIC	"HEAP"		/*heap magic number		*/
+#define H5H_SIZEOF_MAGIC 4
+
 /*
  * Library prototypes...
  */
@@ -31,6 +34,8 @@ off_t H5H_insert (hdf5_file_t *f, haddr_t addr, size_t size, const void *buf);
 herr_t H5H_write (hdf5_file_t *f, haddr_t addr, off_t offset, size_t size,
 		  const void *buf);
 herr_t H5H_remove (hdf5_file_t *f, haddr_t addr, off_t offset, size_t size);
+herr_t H5H_debug (hdf5_file_t *f, haddr_t addr, FILE *stream, intn indent,
+		  intn fwidth);
 
 
 #endif
diff --git a/src/H5Tproto.h b/src/H5Tproto.h
index 5e32b0f..908445e 100644
--- a/src/H5Tproto.h
+++ b/src/H5Tproto.h
@@ -48,6 +48,9 @@ hbool_t H5Tis_atomic(hatom_t tid);
 herr_t H5Tset_type(hatom_t tid,hatom_t base,uint8 len,uint8 arch);
 uintn H5Tsize(hatom_t tid, uint8 len, uint8 arch, hbool_t mem_flag);
 herr_t H5T_release(hatom_t oid);
+herr_t H5Tadd_field (hatom_t tid, const char *name, hatom_t base, uint8 len,
+		     uint8 arch, hatom_t space);
+herr_t H5Tget_fields(hatom_t tid, hatom_t *field_list);
 
 #if defined c_plusplus || defined __cplusplus
 }
diff --git a/src/Makefile b/src/Makefile
index 13eeea4..022f392 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -34,7 +34,7 @@ $(TARGET): $(OBJ)
 	$(AR) $(ARFLAGS) $(TARGET) $(OBJ)
 	$(RANLIB) $(TARGET)
 
-all test: $(TARGET)
+all test: $(TARGET) debug_hdf5
 
 debug: $(OBJ) 
 	$(AR) $(ARFLAGS) $(TARGET) $(OBJ)
@@ -46,6 +46,12 @@ clean:
 
 ###########################################################################
 
+debug_hdf5: $(TARGET) debug.o
+	$(CC) -o debug debug.o -L. -lhdf5
+
+debug.o: debug.c $(INCL)
+	$(CC) $(CFLAGS) debug.c
+
 H5.o:	H5.c  $(INCL) H5private.h H5proto.h
 	$(CC) $(CFLAGS) H5.c
 
diff --git a/src/debug.c b/src/debug.c
new file mode 100644
index 0000000..f061d4c
--- /dev/null
+++ b/src/debug.c
@@ -0,0 +1,142 @@
+/*-------------------------------------------------------------------------
+ * Copyright (C) 1997	National Center for Supercomputing Applications.
+ *                      All rights reserved.
+ *
+ *-------------------------------------------------------------------------
+ *
+ * Created:		debug.c
+ * 			Jul 18 1997
+ * 			Robb Matzke <robb@maya.nuance.com>
+ *
+ * Purpose:		Debugs an existing HDF5 file at a low level.
+ *
+ * Modifications:	
+ *
+ *-------------------------------------------------------------------------
+ */
+#include "hdf5.h"
+
+#include "H5private.h"
+#include "H5Bprivate.h"
+#include "H5Fprivate.h"
+#include "H5Gprivate.h"
+#include "H5Hprivate.h"
+
+#define INDENT	3
+#define VCOL	50
+
+
+/*-------------------------------------------------------------------------
+ * Function:	main
+ *
+ * Usage:	debug FILENAME [OFFSET]
+ *
+ * Return:	Success:	exit (0)
+ *
+ *		Failure:	exit (non-zero)
+ *
+ * Programmer:	Robb Matzke
+ *		robb@maya.nuance.com
+ *		Jul 18 1997
+ *
+ * Modifications:
+ *
+ *-------------------------------------------------------------------------
+ */
+int
+main (int argc, char *argv[])
+{
+   hatom_t	fid;
+   hdf5_file_t	*f;
+   haddr_t	addr = 0;
+   uint8	sig[16];
+   intn		i;
+
+   /*
+    * Parse command arguments.
+    */
+   if (argc>2) {
+      printf ("New address: %s\n", argv[2]);
+      addr = strtol (argv[2], NULL, 0);
+   }
+   
+   /*
+    * Open the file and get the file descriptor.
+    */
+   if ((fid = H5Fopen (argv[1], 0, 0))<0) {
+      fprintf (stderr, "cannot open file\n");
+      exit (1);
+   }
+   if (NULL==(f=H5Aatom_object (fid))) {
+      fprintf (stderr, "cannot obtain hdf5_file_t pointer\n");
+      exit (2);
+   }
+
+   /*
+    * Read the signature at the specified file position.
+    */
+   printf ("Reading signature at byte %lu\n", (unsigned long)addr);
+   if (H5F_block_read (f, addr, sizeof(sig), sig)<0) {
+      fprintf (stderr, "cannot read signature\n");
+      exit (3);
+   }
+
+   if (!memcmp (sig, HDF5_FILE_SIGNATURE, HDF5_FILE_SIGNATURE_LEN)) {
+      /*
+       * Debug the boot block.
+       */
+      H5F_debug (f, 0, stdout, 0, VCOL);
+      
+   } else if (!memcmp (sig, H5H_MAGIC, H5H_SIZEOF_MAGIC)) {
+      /*
+       * Debug a heap.
+       */
+      H5H_debug (f, addr, stdout, 0, VCOL);
+
+   } else if (!memcmp (sig, H5G_NODE_MAGIC, H5G_NODE_SIZEOF_MAGIC)) {
+      /*
+       * Debug a symbol table node.
+       */
+      H5G_node_debug (f, addr, stdout, 0, VCOL);
+
+   } else if (!memcmp (sig, H5B_MAGIC, H5B_SIZEOF_MAGIC)) {
+      /*
+       * Debug a B-tree.  B-trees are debugged through the B-tree
+       * subclass.  The subclass identifier is the byte immediately
+       * after the B-tree signature.
+       */
+      H5B_subid_t subtype = sig[H5B_SIZEOF_MAGIC];
+      switch (subtype) {
+      case H5B_SUBTYPE_SNODE:
+	 H5G_node_debug (f, addr, stdout, 0, VCOL);
+	 break;
+
+      default:
+	 fprintf (stderr, "Unknown B-tree subtype %u\n", (unsigned)(subtype));
+	 exit (4);
+      }
+      
+   } else {
+      /*
+       * Got some other unrecognized signature.
+       */
+      printf ("%-*s ", VCOL, "Signature:");
+      for (i=0; i<8; i++) {
+	 if (sig[i]>' ' && sig[i]<='~' && '\\'!=sig[i]) {
+	    putchar (sig[i]);
+	 } else if ('\\'==sig[i]) {
+	    putchar ('\\');
+	    putchar ('\\');
+	 } else {
+	    printf ("\\%03o", sig[i]);
+	 }
+      }
+      putchar ('\n');
+      
+      fprintf (stderr, "unknown signature\n");
+      exit (4);
+   }
+
+   H5Fclose (fid);
+   exit (0);
+}