path: root/src/H5Gstab.c

/*
 * Copyright (C) 1997 National Center for Supercomputing Applications
 *                    All rights reserved.
 *
 * Programmer: Robb Matzke <matzke@llnl.gov>
 *             Friday, September 19, 1997
 *
 */
#define H5G_PACKAGE

#include <H5private.h>
#include <H5ACprivate.h>
#include <H5Eprivate.h>
#include <H5Gpkg.h>
#include <H5Hprivate.h>
#include <H5MMprivate.h>
#include <H5Oprivate.h>

#define PABLO_MASK	H5G_stab_mask
static hbool_t interface_initialize_g = FALSE;
#define INTERFACE_INIT	NULL


/*-------------------------------------------------------------------------
 * Function:	H5G_stab_create
 *
 * Purpose:	Creates a new empty symbol table (object header, name heap,
 *		and B-tree).  The caller can specify an initial size for the
 *		name heap.  The object header of the group is opened for
 *		write access.
 *
 * 		In order for the B-tree to operate correctly, the first
 *		item in the heap is the empty string, and must appear at
 *		heap offset zero.
 *
 * Errors:
 *
 * Return:	Success:	SUCCEED
 *
 *		Failure:	FAIL
 *
 * Programmer:	Robb Matzke
 *		matzke@llnl.gov
 *		Aug  1 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5G_stab_create (H5F_t *f, size_t init, H5G_entry_t *self/*out*/)
{
   size_t	name;				/*offset of "" name	*/
   H5O_stab_t	stab;				/*symbol table message	*/

   FUNC_ENTER (H5G_stab_create, FAIL);

   /*
    * Check arguments.
    */
   assert (f);
   assert (self);
   init = MAX(init, H5H_SIZEOF_FREE(f)+2);

   /* Create symbol table private heap */
   if (H5H_create (f, H5H_LOCAL, init, &(stab.heap_addr)/*out*/)<0) {
      HRETURN_ERROR (H5E_SYM, H5E_CANTINIT, FAIL, "can't create heap");
   }
   if ((name = H5H_insert (f, &(stab.heap_addr), 1, "")<0)) {
      HRETURN_ERROR (H5E_SYM, H5E_CANTINIT, FAIL, "can't initialize heap");
   }
   /*
    * B-tree's won't work if the first name isn't at the beginning
    * of the heap.
    */
   assert (0==name);

   /* Create the B-tree */
   if (H5B_create (f, H5B_SNODE, NULL, &(stab.btree_addr)/*out*/)<0) {
      HRETURN_ERROR (H5E_SYM, H5E_CANTINIT, FAIL, "can't create B-tree");
   }

   /*
    * Create symbol table object header.  It has a zero link count
    * since nothing refers to it yet.  The link count will be
    * incremented if the object is added to the group directed graph.
    */
   if (H5O_create (f, 4+2*H5F_SIZEOF_ADDR(f), self/*out*/)<0) {
      HRETURN_ERROR (H5E_SYM, H5E_CANTINIT, FAIL, "can't create header");
   }
   
   /*
    * Insert the symbol table message into the object header and the symbol
    * table entry.
    */
   if (H5O_modify (self, H5O_STAB, H5O_NEW_MESG, H5O_FLAG_CONSTANT, &stab)<0) {
      H5O_close (self);
      HRETURN_ERROR (H5E_SYM, H5E_CANTINIT, FAIL, "can't create message");
   }
   self->cache.stab.btree_addr = stab.btree_addr;
   self->cache.stab.heap_addr = stab.heap_addr;
   self->type = H5G_CACHED_STAB;

   FUNC_LEAVE (SUCCEED);
}


/*-------------------------------------------------------------------------
 * Function:	H5G_stab_find
 *
 * Purpose:	Finds a symbol named NAME in the symbol table whose
 *		description is stored in GRP_ENT in file F and returns its
 *	        symbol table entry through OBJ_ENT (which is optional).
 *
 * Errors:
 *
 * Return:	Success:	SUCCEED
 *
 *		Failure:	FAIL
 *
 * Programmer:	Robb Matzke
 *		matzke@llnl.gov
 *		Aug  1 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5G_stab_find (H5G_entry_t *grp_ent, const char *name,
	       H5G_entry_t *obj_ent/*out*/)
{
   H5G_bt_ud1_t         udata;		/*data to pass through B-tree	*/
   H5O_stab_t		stab;		/*symbol table message		*/

   FUNC_ENTER (H5G_stab_find, FAIL);

   /* Check arguments */
   assert (grp_ent);
   assert (grp_ent->file);
   assert (name && *name);

   /* set up the udata */
   if (NULL==H5O_read (grp_ent, H5O_STAB, 0, &stab)) {
      HRETURN_ERROR (H5E_SYM, H5E_BADMESG, FAIL, "can't read message");
   }
   udata.operation = H5G_OPER_FIND;
   udata.name = name;
   udata.heap_addr = stab.heap_addr;

   /* search the B-tree */
   if (H5B_find (grp_ent->file, H5B_SNODE, &(stab.btree_addr), &udata)<0) {
      HRETURN_ERROR (H5E_SYM, H5E_NOTFOUND, FAIL, "not found");
   }

   if (obj_ent) *obj_ent = udata.ent;
   FUNC_LEAVE (SUCCEED);
}


/*-------------------------------------------------------------------------
 * Function:	H5G_stab_insert
 *
 * Purpose:	Insert a new symbol into the table described by GRP_ENT in
 *		file F.  The name of the new symbol is NAME and its symbol
 *		table entry is OBJ_ENT.
 *
 * Errors:
 *
 * Return:	Success:	SUCCEED
 *
 *		Failure:	FAIL
 *
 * Programmer:	Robb Matzke
 *		matzke@llnl.gov
 *		Aug  1 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5G_stab_insert (H5G_entry_t *grp_ent, const char *name, H5G_entry_t *obj_ent)
{
   H5O_stab_t		stab;		/*symbol table message		*/
   H5G_bt_ud1_t		udata;		/*data to pass through B-tree	*/

   FUNC_ENTER (H5G_stab_insert, FAIL);

   /* check arguments */
   assert (grp_ent && grp_ent->file);
   assert (name && *name);
   assert (obj_ent && obj_ent->file);
   assert (grp_ent->file->shared==obj_ent->file->shared);
   
   /* initialize data to pass through B-tree */
   if (NULL==H5O_read (grp_ent, H5O_STAB, 0, &stab)) {
      HRETURN_ERROR (H5E_SYM, H5E_BADMESG, FAIL, "not a symbol table");
   }

   udata.operation = H5G_OPER_INSERT;
   udata.name = name;
   udata.heap_addr = stab.heap_addr;
   udata.ent = *obj_ent;

   /* insert */
   if (H5B_insert (grp_ent->file, H5B_SNODE, &(stab.btree_addr), &udata)<0) {
      HRETURN_ERROR (H5E_SYM, H5E_CANTINSERT, FAIL, "can't insert entry");
   }

   /* update the name offset in the entry */
   obj_ent->name_off = udata.ent.name_off;
   FUNC_LEAVE (SUCCEED);
}


/*-------------------------------------------------------------------------
 * Function:	H5G_stab_list
 *
 * Purpose:	Returns a list of all the symbols in a symbol table.
 *		The caller allocates an array of pointers which this
 *		function will fill in with malloc'd names.  The caller
 *		also allocates an array of symbol table entries which will
 *		be filled in with data from the symbol table.  Each of these
 *		arrays should have at least MAXENTRIES elements.
 *
 * Errors:
 *		SYM       BADMESG       Not a symbol table. 
 *		SYM       CANTLIST      B-tree list failure. 
 *
 * Return:	Success:	The total number of symbols in the
 *				symbol table.  This may exceed MAXENTRIES,
 *				but at most MAXENTRIES values are copied
 *				into the NAMES and ENTRIES arrays.
 *
 *		Failure:	FAIL, the pointers in NAMES are undefined but
 *			 	no memory is allocated.  The values in
 *				ENTRIES are undefined.
 *
 * Programmer:	Robb Matzke
 *		matzke@llnl.gov
 *		Aug  1 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
intn
H5G_stab_list (H5G_entry_t *grp_ent, intn maxentries, char *names[]/*out*/,
	       H5G_entry_t entries[]/*out*/)
{
   H5G_bt_ud2_t		udata;
   H5O_stab_t		stab;
   intn			i;

   FUNC_ENTER (H5G_stab_list, FAIL);

   /* check args */
   assert (grp_ent && grp_ent->file);
   assert (maxentries>=0);

   /* initialize data to pass through B-tree */
   if (NULL==H5O_read (grp_ent, H5O_STAB, 0, &stab)) {
      HRETURN_ERROR (H5E_SYM, H5E_BADMESG, FAIL, "not a symbol table");
   }
   udata.entry = entries;
   udata.name = names;
   udata.heap_addr = stab.heap_addr;
   udata.maxentries = maxentries;
   udata.nsyms = 0;
   if (names) HDmemset (names, 0, maxentries);

   /* list */
   if (H5B_list (grp_ent->file, H5B_SNODE, &(stab.btree_addr), &udata)<0) {
      if (names) {
	 for (i=0; i<maxentries; i++) H5MM_xfree (names[i]);
      }
      HRETURN_ERROR (H5E_SYM, H5E_CANTLIST, FAIL, "b-tree list failure");
   }

   FUNC_LEAVE (udata.nsyms);
}