'\" '\" Copyright (c) 1989-1993 The Regents of the University of California. '\" Copyright (c) 1994-1997 Sun Microsystems, Inc. '\" '\" See the file "license.terms" for information on usage and redistribution '\" of this file, and for a DISCLAIMER OF ALL WARRANTIES. '\" '\" RCS: @(#) $Id: SetVar.3,v 1.9 2004/08/16 14:11:16 msofer Exp $ '\" .so man.macros .TH Tcl_SetVar 3 8.1 Tcl "Tcl Library Procedures" .BS .SH NAME Tcl_SetVar2Ex, Tcl_SetVar, Tcl_SetVar2, Tcl_ObjSetVar2, Tcl_GetVar2Ex, Tcl_GetVar, Tcl_GetVar2, Tcl_ObjGetVar2, Tcl_UnsetVar, Tcl_UnsetVar2 \- manipulate Tcl variables .SH SYNOPSIS .nf \fB#include \fR .sp .VS 8.1 Tcl_Obj * \fBTcl_SetVar2Ex\fR(\fIinterp, name1, name2, newValuePtr, flags\fR) .VE .sp CONST char * \fBTcl_SetVar\fR(\fIinterp, varName, newValue, flags\fR) .sp CONST char * \fBTcl_SetVar2\fR(\fIinterp, name1, name2, newValue, flags\fR) .sp Tcl_Obj * \fBTcl_ObjSetVar2\fR(\fIinterp, part1Ptr, part2Ptr, newValuePtr, flags\fR) .sp .VS 8.1 Tcl_Obj * \fBTcl_GetVar2Ex\fR(\fIinterp, name1, name2, flags\fR) .VE .sp CONST char * \fBTcl_GetVar\fR(\fIinterp, varName, flags\fR) .sp CONST char * \fBTcl_GetVar2\fR(\fIinterp, name1, name2, flags\fR) .sp Tcl_Obj * \fBTcl_ObjGetVar2\fR(\fIinterp, part1Ptr, part2Ptr, flags\fR) .sp int \fBTcl_UnsetVar\fR(\fIinterp, varName, flags\fR) .sp int \fBTcl_UnsetVar2\fR(\fIinterp, name1, name2, flags\fR) .SH ARGUMENTS .AS Tcl_Interp *newValuePtr .AP Tcl_Interp *interp in Interpreter containing variable. .AP "CONST char" *name1 in Contains the name of an array variable (if \fIname2\fR is non-NULL) or (if \fIname2\fR is NULL) either the name of a scalar variable or a complete name including both variable name and index. May include \fB::\fR namespace qualifiers to specify a variable in a particular namespace. .AP "CONST char" *name2 in If non-NULL, gives name of element within array; in this case \fIname1\fR must refer to an array variable. .AP Tcl_Obj *newValuePtr in .VS 8.1 Points to a Tcl object containing the new value for the variable. .VE .AP int flags in OR-ed combination of bits providing additional information. See below for valid values. .AP "CONST char" *varName in Name of variable. May include \fB::\fR namespace qualifiers to specify a variable in a particular namespace. May refer to a scalar variable or an element of an array. .AP "CONST char" *newValue in New value for variable, specified as a null-terminated string. A copy of this value is stored in the variable. .AP Tcl_Obj *part1Ptr in Points to a Tcl object containing the variable's name. The name may include a series of \fB::\fR namespace qualifiers to specify a variable in a particular namespace. May refer to a scalar variable or an element of an array variable. .AP Tcl_Obj *part2Ptr in If non-NULL, points to an object containing the name of an element within an array and \fIpart1Ptr\fR must refer to an array variable. .BE .SH DESCRIPTION .PP These procedures are used to create, modify, read, and delete Tcl variables from C code. .PP .VS 8.1 \fBTcl_SetVar2Ex\fR, \fBTcl_SetVar\fR, \fBTcl_SetVar2\fR, and \fBTcl_ObjSetVar2\fR will create a new variable or modify an existing one. These procedures set the given variable to the value given by \fInewValuePtr\fR or \fInewValue\fR and return a pointer to the variable's new value, which is stored in Tcl's variable structure. \fBTcl_SetVar2Ex\fR and \fBTcl_ObjSetVar2\fR take the new value as a Tcl_Obj and return a pointer to a Tcl_Obj. \fBTcl_SetVar\fR and \fBTcl_SetVar2\fR take the new value as a string and return a string; they are usually less efficient than \fBTcl_ObjSetVar2\fR. Note that the return value may be different than the \fInewValuePtr\fR or .VE \fInewValue\fR argument, due to modifications made by write traces. If an error occurs in setting the variable (e.g. an array variable is referenced without giving an index into the array) NULL is returned and an error message is left in \fIinterp\fR's result if the \fBTCL_LEAVE_ERR_MSG\fR \fIflag\fR bit is set. .PP .VS 8.1 \fBTcl_GetVar2Ex\fR, \fBTcl_GetVar\fR, \fBTcl_GetVar2\fR, and \fBTcl_ObjGetVar2\fR return the current value of a variable. The arguments to these procedures are treated in the same way as the arguments to the procedures described above. Under normal circumstances, the return value is a pointer to the variable's value. For \fBTcl_GetVar2Ex\fR and \fBTcl_ObjGetVar2\fR the value is returned as a pointer to a Tcl_Obj. For \fBTcl_GetVar\fR and \fBTcl_GetVar2\fR the value is returned as a string; this is usually less efficient, so \fBTcl_GetVar2Ex\fR or \fBTcl_ObjGetVar2\fR are preferred. .VE If an error occurs while reading the variable (e.g. the variable doesn't exist or an array element is specified for a scalar variable), then NULL is returned and an error message is left in \fIinterp\fR's result if the \fBTCL_LEAVE_ERR_MSG\fR \fIflag\fR bit is set. .PP \fBTcl_UnsetVar\fR and \fBTcl_UnsetVar2\fR may be used to remove a variable, so that future attempts to read the variable will return an error. The arguments to these procedures are treated in the same way as the arguments to the procedures above. If the variable is successfully removed then TCL_OK is returned. If the variable cannot be removed because it doesn't exist then TCL_ERROR is returned and an error message is left in \fIinterp\fR's result if the \fBTCL_LEAVE_ERR_MSG\fR \fIflag\fR bit is set. If an array element is specified, the given element is removed but the array remains. If an array name is specified without an index, then the entire array is removed. .PP The name of a variable may be specified to these procedures in four ways: .IP [1] If \fBTcl_SetVar\fR, \fBTcl_GetVar\fR, or \fBTcl_UnsetVar\fR is invoked, the variable name is given as a single string, \fIvarName\fR. If \fIvarName\fR contains an open parenthesis and ends with a close parenthesis, then the value between the parentheses is treated as an index (which can have any string value) and the characters before the first open parenthesis are treated as the name of an array variable. If \fIvarName\fR doesn't have parentheses as described above, then the entire string is treated as the name of a scalar variable. .IP [2] If the \fIname1\fR and \fIname2\fR arguments are provided and \fIname2\fR is non-NULL, then an array element is specified and the array name and index have already been separated by the caller: \fIname1\fR contains the name and \fIname2\fR contains the index. .VS 8.1 An error is generated if \fIname1\fR contains an open parenthesis and ends with a close parenthesis (array element) and \fIname2\fR is non-NULL. .IP [3] If \fIname2\fR is NULL, \fIname1\fR is treated just like \fIvarName\fR in case [1] above (it can be either a scalar or an array element variable name). .VE .PP The \fIflags\fR argument may be used to specify any of several options to the procedures. It consists of an OR-ed combination of the following bits. .TP \fBTCL_GLOBAL_ONLY\fR Under normal circumstances the procedures look up variables as follows. If a procedure call is active in \fIinterp\fR, the variable is looked up at the current level of procedure call. Otherwise, the variable is looked up first in the current namespace, then in the global namespace. However, if this bit is set in \fIflags\fR then the variable is looked up only in the global namespace even if there is a procedure call active. If both \fBTCL_GLOBAL_ONLY\fR and \fBTCL_NAMESPACE_ONLY\fR are given, \fBTCL_GLOBAL_ONLY\fR is ignored. .TP \fBTCL_NAMESPACE_ONLY\fR If this bit is set in \fIflags\fR then the variable is looked up only in the current namespace; if a procedure is active its variables are ignored, and the global namespace is also ignored unless it is the current namespace. .TP \fBTCL_LEAVE_ERR_MSG\fR If an error is returned and this bit is set in \fIflags\fR, then an error message will be left in the interpreter's result, where it can be retrieved with \fBTcl_GetObjResult\fR or \fBTcl_GetStringResult\fR. If this flag bit isn't set then no error message is left and the interpreter's result will not be modified. .TP \fBTCL_APPEND_VALUE\fR If this bit is set then \fInewValuePtr\fR or \fInewValue\fR is appended to the current value instead of replacing it. If the variable is currently undefined, then the bit is ignored. This bit is only used by the \fBTcl_Set*\fR procedures. .TP \fBTCL_LIST_ELEMENT\fR If this bit is set, then \fInewValue\fR is converted to a valid Tcl list element before setting (or appending to) the variable. A separator space is appended before the new list element unless the list element is going to be the first element in a list or sublist (i.e. the variable's current value is empty, or contains the single character ``{'', or ends in `` }''). When appending, the original value of the variable must also be a valid list, so that the operation is the appending of a new list element onto a list. .PP \fBTcl_GetVar\fR and \fBTcl_GetVar2\fR return the current value of a variable. The arguments to these procedures are treated in the same way as the arguments to \fBTcl_SetVar\fR and \fBTcl_SetVar2\fR. Under normal circumstances, the return value is a pointer to the variable's value (which is stored in Tcl's variable structure and will not change before the next call to \fBTcl_SetVar\fR or \fBTcl_SetVar2\fR). \fBTcl_GetVar\fR and \fBTcl_GetVar2\fR use the flag bits TCL_GLOBAL_ONLY and TCL_LEAVE_ERR_MSG, both of which have the same meaning as for \fBTcl_SetVar\fR. If an error occurs in reading the variable (e.g. the variable doesn't exist or an array element is specified for a scalar variable), then NULL is returned. .PP \fBTcl_UnsetVar\fR and \fBTcl_UnsetVar2\fR may be used to remove a variable, so that future calls to \fBTcl_GetVar\fR or \fBTcl_GetVar2\fR for the variable will return an error. The arguments to these procedures are treated in the same way as the arguments to \fBTcl_GetVar\fR and \fBTcl_GetVar2\fR. If the variable is successfully removed then TCL_OK is returned. If the variable cannot be removed because it doesn't exist then TCL_ERROR is returned. If an array element is specified, the given element is removed but the array remains. If an array name is specified without an index, then the entire array is removed. .SH "SEE ALSO" Tcl_GetObjResult, Tcl_GetStringResult, Tcl_TraceVar .SH KEYWORDS array, get variable, interpreter, object, scalar, set, unset, variable id='n58' href='#n58'>58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 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/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *
 * 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: 	Robb Matzke <matzke@llnl.gov>
 *	       	Wednesday, October  8, 1997
 *
 * Purpose:	Indexed (chunked) I/O functions.  The logical
 *		multi-dimensional data space is regularly partitioned into
 *		same-sized "chunks", the first of which is aligned with the
 *		logical origin.  The chunks are given a multi-dimensional
 *		index which is used as a lookup key in a B-tree that maps
 *		chunk index to disk address.  Each chunk can be compressed
 *		independently and the chunks may move around in the file as
 *		their storage requirements change.
 *
 * Cache:	Disk I/O is performed in units of chunks and H5MF_alloc()
 *		contains code to optionally align chunks on disk block
 *		boundaries for performance.
 *
 *		The chunk cache is an extendible hash indexed by a function
 *		of storage B-tree address and chunk N-dimensional offset
 *		within the dataset.  Collisions are not resolved -- one of
 *		the two chunks competing for the hash slot must be preempted
 *		from the cache.  All entries in the hash also participate in
 *		a doubly-linked list and entries are penalized by moving them
 *		toward the front of the list.  When a new chunk is about to
 *		be added to the cache the heap is pruned by preempting
 *		entries near the front of the list to make room for the new
 *		entry which is added to the end of the list.
 */

#define H5F_PACKAGE		/*suppress error about including H5Fpkg	  */

#include "H5private.h"
#include "H5Bprivate.h"		/*B-link trees				*/
#include "H5Dprivate.h"
#include "H5Eprivate.h"
#include "H5Fpkg.h"
#include "H5FLprivate.h"	/*Free Lists	  */
#include "H5Iprivate.h"
#include "H5MFprivate.h"
#include "H5MMprivate.h"
#include "H5Oprivate.h"
#include "H5Pprivate.h"         /* Property lists */
#include "H5Sprivate.h"         /* Dataspaces */
#include "H5Vprivate.h"

/* MPIO, MPIPOSIX, & FPHDF5 drivers needed for special checks */
#include "H5FDfphdf5.h"
#include "H5FDmpio.h"
#include "H5FDmpiposix.h"

/*
 * Feature: If this constant is defined then every cache preemption and load
 *	    causes a character to be printed on the standard error stream:
 *
 *     `.': Entry was preempted because it has been completely read or
 *	    completely written but not partially read and not partially
 *	    written. This is often a good reason for preemption because such
 *	    a chunk will be unlikely to be referenced in the near future.
 *
 *     `:': Entry was preempted because it hasn't been used recently.
 *
 *     `#': Entry was preempted because another chunk collided with it. This
 *	    is usually a relatively bad thing.  If there are too many of
 *	    these then the number of entries in the cache can be increased.
 *
 *       c: Entry was preempted because the file is closing.
 *
 *	 w: A chunk read operation was eliminated because the library is
 *	    about to write new values to the entire chunk.  This is a good
 *	    thing, especially on files where the chunk size is the same as
 *	    the disk block size, chunks are aligned on disk block boundaries,
 *	    and the operating system can also eliminate a read operation.
 */

/*#define H5F_ISTORE_DEBUG */

/* Interface initialization */
#define PABLO_MASK	H5Fistore_mask
static int		interface_initialize_g = 0;
#define INTERFACE_INIT NULL

/*
 * Given a B-tree node return the dimensionality of the chunks pointed to by
 * that node.
 */
#define H5F_ISTORE_NDIMS(X)	((int)(((X)->sizeof_rkey-8)/8))

/* Raw data chunks are cached.  Each entry in the cache is: */
typedef struct H5F_rdcc_ent_t {
    hbool_t	locked;		/*entry is locked in cache		*/
    hbool_t	dirty;		/*needs to be written to disk?		*/
    H5O_layout_t *layout;	/*the layout message			*/
    double	split_ratios[3];/*B-tree node splitting ratios		*/
    H5O_pline_t	*pline;		/*filter pipeline message		*/
    hssize_t	offset[H5O_LAYOUT_NDIMS]; /*chunk name			*/
    size_t	rd_count;	/*bytes remaining to be read		*/
    size_t	wr_count;	/*bytes remaining to be written		*/
    size_t	chunk_size;	/*size of a chunk			*/
    size_t	alloc_size;	/*amount allocated for the chunk	*/
    uint8_t	*chunk;		/*the unfiltered chunk data		*/
    unsigned	idx;		/*index in hash table			*/
    struct H5F_rdcc_ent_t *next;/*next item in doubly-linked list	*/
    struct H5F_rdcc_ent_t *prev;/*previous item in doubly-linked list	*/
} H5F_rdcc_ent_t;
typedef H5F_rdcc_ent_t *H5F_rdcc_ent_ptr_t; /* For free lists */

/* Private prototypes */
static size_t H5F_istore_sizeof_rkey(H5F_t *f, const void *_udata);
static herr_t H5F_istore_new_node(H5F_t *f, hid_t dxpl_id, H5B_ins_t, void *_lt_key,
				  void *_udata, void *_rt_key,
				  haddr_t *addr_p /*out*/);
static int H5F_istore_cmp2(H5F_t *f, hid_t dxpl_id, void *_lt_key, void *_udata,
			    void *_rt_key);
static int H5F_istore_cmp3(H5F_t *f, hid_t dxpl_id, void *_lt_key, void *_udata,
			    void *_rt_key);
static herr_t H5F_istore_found(H5F_t *f, hid_t dxpl_id, haddr_t addr, const void *_lt_key,
			       void *_udata, const void *_rt_key);
static H5B_ins_t H5F_istore_insert(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_lt_key,
				   hbool_t *lt_key_changed, void *_md_key,
				   void *_udata, void *_rt_key,
				   hbool_t *rt_key_changed,
				   haddr_t *new_node/*out*/);
static H5B_iterate_t H5F_istore_iter_allocated(H5F_t *f, hid_t dxpl_id, void *left_key, haddr_t addr,
				 void *right_key, void *_udata);
static H5B_iterate_t H5F_istore_iter_dump(H5F_t *f, hid_t dxpl_id, void *left_key, haddr_t addr,
				 void *right_key, void *_udata);
static herr_t H5F_istore_decode_key(H5F_t *f, H5B_t *bt, uint8_t *raw,
				    void *_key);
static herr_t H5F_istore_encode_key(H5F_t *f, H5B_t *bt, uint8_t *raw,
				    void *_key);
static herr_t H5F_istore_debug_key(FILE *stream, H5F_t *f, hid_t dxpl_id,
                                int indent, int fwidth, const void *key,
                                    const void *udata);
static haddr_t H5F_istore_get_addr(H5F_t *f, hid_t dxpl_id, const H5O_layout_t *layout,
				  const hssize_t offset[]);
static H5B_iterate_t H5F_istore_prune_extent(H5F_t *f, hid_t dxpl_id, void *_lt_key, haddr_t addr,
        void *_rt_key, void *_udata);
static H5B_ins_t H5F_istore_remove( H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_lt_key,
                  hbool_t *lt_key_changed, void *_udata, void *_rt_key,
                  hbool_t *rt_key_changed);

/*
 * B-tree key.	A key contains the minimum logical N-dimensional address and
 * the logical size of the chunk to which this key refers.  The
 * fastest-varying dimension is assumed to reference individual bytes of the
 * array, so a 100-element 1-d array of 4-byte integers would really be a 2-d
 * array with the slow varying dimension of size 100 and the fast varying
 * dimension of size 4 (the storage dimensionality has very little to do with
 * the real dimensionality).
 *
 * Only the first few values of the OFFSET and SIZE fields are actually
 * stored on disk, depending on the dimensionality.
 *
 * The chunk's file address is part of the B-tree and not part of the key.
 */
typedef struct H5F_istore_key_t {
    size_t	nbytes;				/*size of stored data	*/
    hssize_t	offset[H5O_LAYOUT_NDIMS];	/*logical offset to start*/
    unsigned	filter_mask;			/*excluded filters	*/
} H5F_istore_key_t;

typedef struct H5F_istore_ud1_t {
    H5F_istore_key_t	key;	                /*key values		*/
    haddr_t		addr;			/*file address of chunk */
    H5O_layout_t	mesg;		        /*layout message	*/
    hsize_t		total_storage;	        /*output from iterator	*/
    FILE		*stream;		/*debug output stream	*/
    hsize_t		*dims;		        /*dataset dimensions	*/
} H5F_istore_ud1_t;

/* inherits B-tree like properties from H5B */
H5B_class_t H5B_ISTORE[1] = {{
    H5B_ISTORE_ID,		/*id			*/
    sizeof(H5F_istore_key_t),	/*sizeof_nkey		*/
    H5F_istore_sizeof_rkey, 	/*get_sizeof_rkey	*/
    H5F_istore_new_node,	/*new			*/
    H5F_istore_cmp2,		/*cmp2			*/
    H5F_istore_cmp3,		/*cmp3			*/
    H5F_istore_found,		/*found			*/
    H5F_istore_insert,		/*insert		*/
    FALSE,			/*follow min branch?	*/
    FALSE,			/*follow max branch?	*/
    H5F_istore_remove,          /*remove		*/
    H5F_istore_decode_key,	/*decode		*/
    H5F_istore_encode_key,	/*encode		*/
    H5F_istore_debug_key,	/*debug			*/
}};

#define H5F_HASH_DIVISOR 1     /* Attempt to spread out the hashing */
                               /* This should be the same size as the alignment of */
                               /* of the smallest file format object written to the file.  */
#define H5F_HASH(F,ADDR) H5F_addr_hash((ADDR/H5F_HASH_DIVISOR),(F)->shared->rdcc.nslots)


/* Declare a free list to manage H5F_rdcc_ent_t objects */
H5FL_DEFINE_STATIC(H5F_rdcc_ent_t);

/* Declare a PQ free list to manage the H5F_rdcc_ent_ptr_t array information */
H5FL_ARR_DEFINE_STATIC(H5F_rdcc_ent_ptr_t,-1);


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_sizeof_rkey
 *
 * Purpose:	Returns the size of a raw key for the specified UDATA.	The
 *		size of the key is dependent on the number of dimensions for
 *		the object to which this B-tree points.	 The dimensionality
 *		of the UDATA is the only portion that's referenced here.
 *
 * Return:	Success:	Size of raw key in bytes.
 *
 *		Failure:	abort()
 *
 * Programmer:	Robb Matzke
 *		Wednesday, October  8, 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static size_t
H5F_istore_sizeof_rkey(H5F_t UNUSED *f, const void *_udata)
{
    const H5F_istore_ud1_t *udata = (const H5F_istore_ud1_t *) _udata;
    size_t		    nbytes;

    /* Use FUNC_ENTER_NOINIT here to avoid performance issues */
    FUNC_ENTER_NOINIT(H5F_istore_sizeof_rkey);

    assert(udata);
    assert(udata->mesg.ndims > 0 && udata->mesg.ndims <= H5O_LAYOUT_NDIMS);

    nbytes = 4 +			/*storage size		*/
	     4 +			/*filter mask		*/
	     udata->mesg.ndims*8;	/*dimension indices	*/

    FUNC_LEAVE_NOAPI(nbytes);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_decode_key
 *
 * Purpose:	Decodes a raw key into a native key for the B-tree
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *		Friday, October 10, 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5F_istore_decode_key(H5F_t UNUSED *f, H5B_t *bt, uint8_t *raw, void *_key)
{
    H5F_istore_key_t	*key = (H5F_istore_key_t *) _key;
    int		i;
    int		ndims = H5F_ISTORE_NDIMS(bt);
    herr_t ret_value=SUCCEED;   /* Return value */

    FUNC_ENTER_NOAPI(H5F_istore_decode_key, FAIL);

    /* check args */
    assert(f);
    assert(bt);
    assert(raw);
    assert(key);
    assert(ndims>0 && ndims<=H5O_LAYOUT_NDIMS);

    /* decode */
    UINT32DECODE(raw, key->nbytes);
    UINT32DECODE(raw, key->filter_mask);
    for (i=0; i<ndims; i++)
	UINT64DECODE(raw, key->offset[i]);

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_encode_key
 *
 * Purpose:	Encode a key from native format to raw format.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *		Friday, October 10, 1997
 *
 * Modifications:
 *	
 *-------------------------------------------------------------------------
 */
static herr_t
H5F_istore_encode_key(H5F_t UNUSED *f, H5B_t *bt, uint8_t *raw, void *_key)
{
    H5F_istore_key_t	*key = (H5F_istore_key_t *) _key;
    int		ndims = H5F_ISTORE_NDIMS(bt);
    int		i;
    herr_t ret_value=SUCCEED;   /* Return value */

    FUNC_ENTER_NOAPI(H5F_istore_encode_key, FAIL);

    /* check args */
    assert(f);
    assert(bt);
    assert(raw);
    assert(key);
    assert(ndims>0 && ndims<=H5O_LAYOUT_NDIMS);

    /* encode */
    UINT32ENCODE(raw, key->nbytes);
    UINT32ENCODE(raw, key->filter_mask);
    for (i=0; i<ndims; i++)
	UINT64ENCODE(raw, key->offset[i]);

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_debug_key
 *
 * Purpose:	Prints a key.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *              Thursday, April 16, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5F_istore_debug_key (FILE *stream, H5F_t UNUSED *f, hid_t UNUSED dxpl_id, int indent, int fwidth,
		      const void *_key, const void *_udata)
{
    const H5F_istore_key_t	*key = (const H5F_istore_key_t *)_key;
    const H5F_istore_ud1_t	*udata = (const H5F_istore_ud1_t *)_udata;
    unsigned		u;
    herr_t ret_value=SUCCEED;   /* Return value */
    
    FUNC_ENTER_NOAPI(H5F_istore_debug_key, FAIL);

    assert (key);

    HDfprintf(stream, "%*s%-*s %Zd bytes\n", indent, "", fwidth,
	      "Chunk size:", key->nbytes);
    HDfprintf(stream, "%*s%-*s 0x%08x\n", indent, "", fwidth,
	      "Filter mask:", key->filter_mask);
    HDfprintf(stream, "%*s%-*s {", indent, "", fwidth,
	      "Logical offset:");
    for (u=0; u<udata->mesg.ndims; u++)
        HDfprintf (stream, "%s%Hd", u?", ":"", key->offset[u]);
    HDfputs ("}\n", stream);

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_cmp2
 *
 * Purpose:	Compares two keys sort of like strcmp().  The UDATA pointer
 *		is only to supply extra information not carried in the keys
 *		(in this case, the dimensionality) and is not compared
 *		against the keys.
 *
 * Return:	Success:	-1 if LT_KEY is less than RT_KEY;
 *				1 if LT_KEY is greater than RT_KEY;
 *				0 if LT_KEY and RT_KEY are equal.
 *
 *		Failure:	FAIL (same as LT_KEY<RT_KEY)
 *
 * Programmer:	Robb Matzke
 *		Thursday, November  6, 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static int
H5F_istore_cmp2(H5F_t UNUSED *f, hid_t UNUSED dxpl_id, void *_lt_key, void *_udata,
		void *_rt_key)
{
    H5F_istore_key_t	*lt_key = (H5F_istore_key_t *) _lt_key;
    H5F_istore_key_t	*rt_key = (H5F_istore_key_t *) _rt_key;
    H5F_istore_ud1_t	*udata = (H5F_istore_ud1_t *) _udata;
    int		ret_value;

    FUNC_ENTER_NOAPI(H5F_istore_cmp2, FAIL);

    assert(lt_key);
    assert(rt_key);
    assert(udata);
    assert(udata->mesg.ndims > 0 && udata->mesg.ndims <= H5O_LAYOUT_NDIMS);

    /* Compare the offsets but ignore the other fields */
    ret_value = H5V_vector_cmp_s(udata->mesg.ndims, lt_key->offset, rt_key->offset);

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_cmp3
 *
 * Purpose:	Compare the requested datum UDATA with the left and right
 *		keys of the B-tree.
 *
 * Return:	Success:	negative if the min_corner of UDATA is less
 *				than the min_corner of LT_KEY.
 *
 *				positive if the min_corner of UDATA is
 *				greater than or equal the min_corner of
 *				RT_KEY.
 *
 *				zero otherwise.	 The min_corner of UDATA is
 *				not necessarily contained within the address
 *				space represented by LT_KEY, but a key that
 *				would describe the UDATA min_corner address
 *				would fall lexicographically between LT_KEY
 *				and RT_KEY.
 *				
 *		Failure:	FAIL (same as UDATA < LT_KEY)
 *
 * Programmer:	Robb Matzke
 *		Wednesday, October  8, 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static int
H5F_istore_cmp3(H5F_t UNUSED *f, hid_t UNUSED dxpl_id, void *_lt_key, void *_udata,
		void *_rt_key)
{
    H5F_istore_key_t	*lt_key = (H5F_istore_key_t *) _lt_key;
    H5F_istore_key_t	*rt_key = (H5F_istore_key_t *) _rt_key;
    H5F_istore_ud1_t	*udata = (H5F_istore_ud1_t *) _udata;
    int		ret_value = 0;

    FUNC_ENTER_NOAPI(H5F_istore_cmp3, FAIL);

    assert(lt_key);
    assert(rt_key);
    assert(udata);
    assert(udata->mesg.ndims > 0 && udata->mesg.ndims <= H5O_LAYOUT_NDIMS);

    if (H5V_vector_lt_s(udata->mesg.ndims, udata->key.offset,
			lt_key->offset)) {
	ret_value = -1;
    } else if (H5V_vector_ge_s(udata->mesg.ndims, udata->key.offset,
			     rt_key->offset)) {
	ret_value = 1;
    }

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_new_node
 *
 * Purpose:	Adds a new entry to an i-storage B-tree.  We can assume that
 *		the domain represented by UDATA doesn't intersect the domain
 *		already represented by the B-tree.
 *
 * Return:	Success:	Non-negative. The address of leaf is returned
 *				through the ADDR argument.  It is also added
 *				to the UDATA.
 *
 * 		Failure:	Negative
 *
 * Programmer:	Robb Matzke
 *		Tuesday, October 14, 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5F_istore_new_node(H5F_t *f, hid_t dxpl_id, H5B_ins_t op,
		    void *_lt_key, void *_udata, void *_rt_key,
		    haddr_t *addr_p/*out*/)
{
    H5F_istore_key_t	*lt_key = (H5F_istore_key_t *) _lt_key;
    H5F_istore_key_t	*rt_key = (H5F_istore_key_t *) _rt_key;
    H5F_istore_ud1_t	*udata = (H5F_istore_ud1_t *) _udata;
    unsigned		u;
    herr_t      ret_value=SUCCEED;       /* Return value */

    FUNC_ENTER_NOAPI(H5F_istore_new_node, FAIL);

    /* check args */
    assert(f);
    assert(lt_key);
    assert(rt_key);
    assert(udata);
    assert(udata->mesg.ndims > 0 && udata->mesg.ndims < H5O_LAYOUT_NDIMS);
    assert(addr_p);

    /* Allocate new storage */
    assert (udata->key.nbytes > 0);
    H5_CHECK_OVERFLOW( udata->key.nbytes ,size_t, hsize_t);
    if (HADDR_UNDEF==(*addr_p=H5MF_alloc(f, H5FD_MEM_DRAW, dxpl_id, (hsize_t)udata->key.nbytes)))
        HGOTO_ERROR(H5E_IO, H5E_CANTINIT, FAIL, "couldn't allocate new file storage");
    udata->addr = *addr_p;

    /*
     * The left key describes the storage of the UDATA chunk being
     * inserted into the tree.
     */
    lt_key->nbytes = udata->key.nbytes;
    lt_key->filter_mask = udata->key.filter_mask;
    for (u=0; u<udata->mesg.ndims; u++)
        lt_key->offset[u] = udata->key.offset[u];

    /*
     * The right key might already be present.  If not, then add a zero-width
     * chunk.
     */
    if (H5B_INS_LEFT != op) {
        rt_key->nbytes = 0;
        rt_key->filter_mask = 0;
        for (u=0; u<udata->mesg.ndims; u++) {
            assert (udata->mesg.dim[u] < HSSIZET_MAX);
            assert (udata->key.offset[u]+(hssize_t)(udata->mesg.dim[u]) >
                udata->key.offset[u]);
            rt_key->offset[u] = udata->key.offset[u] +
                    (hssize_t)(udata->mesg.dim[u]);
        }
    }

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_found
 *
 * Purpose:	This function is called when the B-tree search engine has
 *		found the leaf entry that points to a chunk of storage that
 *		contains the beginning of the logical address space
 *		represented by UDATA.  The LT_KEY is the left key (the one
 *		that describes the chunk) and RT_KEY is the right key (the
 *		one that describes the next or last chunk).
 *
 * Note:	It's possible that the chunk isn't really found.  For
 *		instance, in a sparse dataset the requested chunk might fall
 *		between two stored chunks in which case this function is
 *		called with the maximum stored chunk indices less than the
 *		requested chunk indices.
 *
 * Return:	Non-negative on success with information about the chunk
 *		returned through the UDATA argument. Negative on failure.
 *
 * Programmer:	Robb Matzke
 *		Thursday, October  9, 1997
 *
 * Modifications:
 *		Robb Matzke, 1999-07-28
 *		The ADDR argument is passed by value.
 *-------------------------------------------------------------------------
 */
static herr_t
H5F_istore_found(H5F_t UNUSED *f, hid_t UNUSED dxpl_id, haddr_t addr, const void *_lt_key,
		 void *_udata, const void UNUSED *_rt_key)
{
    H5F_istore_ud1_t	   *udata = (H5F_istore_ud1_t *) _udata;
    const H5F_istore_key_t *lt_key = (const H5F_istore_key_t *) _lt_key;
    unsigned		u;
    herr_t      ret_value=SUCCEED;       /* Return value */

    FUNC_ENTER_NOAPI(H5F_istore_found, FAIL);

    /* Check arguments */
    assert(f);
    assert(H5F_addr_defined(addr));
    assert(udata);
    assert(lt_key);

    /* Is this *really* the requested chunk? */
    for (u=0; u<udata->mesg.ndims; u++) {
        if (udata->key.offset[u] >= lt_key->offset[u]+(hssize_t)(udata->mesg.dim[u]))
            HGOTO_DONE(FAIL);
    }

    /* Initialize return values */
    udata->addr = addr;
    udata->key.nbytes = lt_key->nbytes;
    udata->key.filter_mask = lt_key->filter_mask;
    assert (lt_key->nbytes>0);
    for (u = 0; u < udata->mesg.ndims; u++)
        udata->key.offset[u] = lt_key->offset[u];

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_insert
 *
 * Purpose:	This function is called when the B-tree insert engine finds
 *		the node to use to insert new data.  The UDATA argument
 *		points to a struct that describes the logical addresses being
 *		added to the file.  This function allocates space for the
 *		data and returns information through UDATA describing a
 *		file chunk to receive (part of) the data.
 *
 *		The LT_KEY is always the key describing the chunk of file
 *		memory at address ADDR. On entry, UDATA describes the logical
 *		addresses for which storage is being requested (through the
 *		`offset' and `size' fields). On return, UDATA describes the
 *		logical addresses contained in a chunk on disk.
 *
 * Return:	Success:	An insertion command for the caller, one of
 *				the H5B_INS_* constants.  The address of the
 *				new chunk is returned through the NEW_NODE
 *				argument.
 *
 *		Failure:	H5B_INS_ERROR
 *
 * Programmer:	Robb Matzke
 *		Thursday, October  9, 1997
 *
 * Modifications:
 *		Robb Matzke, 1999-07-28
 *		The ADDR argument is passed by value. The NEW_NODE argument
 *		is renamed NEW_NODE_P.
 *-------------------------------------------------------------------------
 */
static H5B_ins_t
H5F_istore_insert(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_lt_key,
		  hbool_t UNUSED *lt_key_changed,
		  void *_md_key, void *_udata, void *_rt_key,
		  hbool_t UNUSED *rt_key_changed,
		  haddr_t *new_node_p/*out*/)
{
    H5F_istore_key_t	*lt_key = (H5F_istore_key_t *) _lt_key;
    H5F_istore_key_t	*md_key = (H5F_istore_key_t *) _md_key;
    H5F_istore_key_t	*rt_key = (H5F_istore_key_t *) _rt_key;
    H5F_istore_ud1_t	*udata = (H5F_istore_ud1_t *) _udata;
    int		cmp;
    unsigned		u;
    H5B_ins_t		ret_value;

    FUNC_ENTER_NOAPI(H5F_istore_insert, H5B_INS_ERROR);

    /* check args */
    assert(f);
    assert(H5F_addr_defined(addr));
    assert(lt_key);
    assert(lt_key_changed);
    assert(md_key);
    assert(udata);
    assert(rt_key);
    assert(rt_key_changed);
    assert(new_node_p);

    cmp = H5F_istore_cmp3(f, dxpl_id, lt_key, udata, rt_key);
    assert(cmp <= 0);

    if (cmp < 0) {
        /* Negative indices not supported yet */
        assert("HDF5 INTERNAL ERROR -- see rpm" && 0);
        HGOTO_ERROR(H5E_STORAGE, H5E_UNSUPPORTED, H5B_INS_ERROR, "internal error");
	
    } else if (H5V_vector_eq_s (udata->mesg.ndims,
				udata->key.offset, lt_key->offset) &&
	       lt_key->nbytes>0) {
        /*
         * Already exists.  If the new size is not the same as the old size
         * then we should reallocate storage.
         */
        if (lt_key->nbytes != udata->key.nbytes) {
/* Currently, the old chunk data is "thrown away" after the space is reallocated,
 * so avoid data copy in H5MF_realloc() call by just free'ing the space and
 * allocating new space.
 * 
 * This should keep the file smaller also, by freeing the space and then
 * allocating new space, instead of vice versa (in H5MF_realloc).
 *
 * QAK - 11/19/2002
 */
#ifdef OLD_WAY
            if (HADDR_UNDEF==(*new_node_p=H5MF_realloc(f, H5FD_MEM_DRAW, addr,
                      (hsize_t)lt_key->nbytes, (hsize_t)udata->key.nbytes)))
                HGOTO_ERROR (H5E_STORAGE, H5E_NOSPACE, H5B_INS_ERROR, "unable to reallocate chunk storage");
#else /* OLD_WAY */
            H5_CHECK_OVERFLOW( lt_key->nbytes ,size_t, hsize_t);
            if (H5MF_xfree(f, H5FD_MEM_DRAW, dxpl_id, addr, (hsize_t)lt_key->nbytes)<0)
                HGOTO_ERROR(H5E_STORAGE, H5E_CANTFREE, H5B_INS_ERROR, "unable to free chunk");
            H5_CHECK_OVERFLOW( udata->key.nbytes ,size_t, hsize_t);
            if (HADDR_UNDEF==(*new_node_p=H5MF_alloc(f, H5FD_MEM_DRAW, dxpl_id, (hsize_t)udata->key.nbytes)))
                HGOTO_ERROR(H5E_STORAGE, H5E_NOSPACE, H5B_INS_ERROR, "unable to reallocate chunk");
#endif /* OLD_WAY */
            lt_key->nbytes = udata->key.nbytes;
            lt_key->filter_mask = udata->key.filter_mask;
            *lt_key_changed = TRUE;
            udata->addr = *new_node_p;
            ret_value = H5B_INS_CHANGE;
        } else {
            udata->addr = addr;
            ret_value = H5B_INS_NOOP;
        }

    } else if (H5V_hyper_disjointp(udata->mesg.ndims,
				   lt_key->offset, udata->mesg.dim,
				   udata->key.offset, udata->mesg.dim)) {
        assert(H5V_hyper_disjointp(udata->mesg.ndims,
				   rt_key->offset, udata->mesg.dim,
				   udata->key.offset, udata->mesg.dim));
        /*
         * Split this node, inserting the new new node to the right of the
         * current node.  The MD_KEY is where the split occurs.
         */
        md_key->nbytes = udata->key.nbytes;
        md_key->filter_mask = udata->key.filter_mask;
        for (u=0; u<udata->mesg.ndims; u++) {
            assert(0 == udata->key.offset[u] % udata->mesg.dim[u]);
            md_key->offset[u] = udata->key.offset[u];
        }

        /*
         * Allocate storage for the new chunk
         */
        H5_CHECK_OVERFLOW( udata->key.nbytes ,size_t, hsize_t);
        if (HADDR_UNDEF==(*new_node_p=H5MF_alloc(f, H5FD_MEM_DRAW, dxpl_id, (hsize_t)udata->key.nbytes)))
            HGOTO_ERROR(H5E_STORAGE, H5E_NOSPACE, H5B_INS_ERROR, "file allocation failed");
        udata->addr = *new_node_p;
        ret_value = H5B_INS_RIGHT;

    } else {
        assert("HDF5 INTERNAL ERROR -- see rpm" && 0);
        HGOTO_ERROR(H5E_IO, H5E_UNSUPPORTED, H5B_INS_ERROR, "internal error");
    }

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_iter_allocated
 *
 * Purpose:	Simply counts the number of chunks for a dataset.
 *
 * Return:	Success:	Non-negative
 *
 *		Failure:	Negative
 *
 * Programmer:	Robb Matzke
 *              Wednesday, April 21, 1999
 *
 * Modifications:
 *		Robb Matzke, 1999-07-28
 *		The ADDR argument is passed by value.
 *
 *		Quincey Koziol, 2002-04-22
 *		Changed to callback from H5B_iterate
 *-------------------------------------------------------------------------
 */
static H5B_iterate_t 
H5F_istore_iter_allocated (H5F_t UNUSED *f, hid_t UNUSED dxpl_id, void *_lt_key, haddr_t UNUSED addr,
		    void UNUSED *_rt_key, void *_udata)
{
    H5F_istore_ud1_t	*bt_udata = (H5F_istore_ud1_t *)_udata;
    H5F_istore_key_t	*lt_key = (H5F_istore_key_t *)_lt_key;

    FUNC_ENTER_NOINIT(H5F_istore_iter_allocated);

    bt_udata->total_storage += lt_key->nbytes;

    FUNC_LEAVE_NOAPI(H5B_ITER_CONT);
} /* H5F_istore_iter_allocated() */


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_iter_dump
 *
 * Purpose:	If the UDATA.STREAM member is non-null then debugging
 *              information is written to that stream.
 *
 * Return:	Success:	Non-negative
 *
 *		Failure:	Negative
 *
 * Programmer:	Robb Matzke
 *              Wednesday, April 21, 1999
 *
 * Modifications:
 *		Robb Matzke, 1999-07-28
 *		The ADDR argument is passed by value.
 *
 *		Quincey Koziol, 2002-04-22
 *		Changed to callback from H5B_iterate
 *-------------------------------------------------------------------------
 */
static H5B_iterate_t
H5F_istore_iter_dump (H5F_t UNUSED *f, hid_t UNUSED dxpl_id, void *_lt_key, haddr_t UNUSED addr,
		    void UNUSED *_rt_key, void *_udata)
{
    H5F_istore_ud1_t	*bt_udata = (H5F_istore_ud1_t *)_udata;
    H5F_istore_key_t	*lt_key = (H5F_istore_key_t *)_lt_key;
    unsigned		u;

    FUNC_ENTER_NOINIT(H5F_istore_iter_dump);

    if (bt_udata->stream) {
        if (0==bt_udata->total_storage) {
            fprintf(bt_udata->stream,
                "             Flags    Bytes    Address Logical Offset\n");
            fprintf(bt_udata->stream,
                "        ========== ======== ========== "
                "==============================\n");
        }
        HDfprintf(bt_udata->stream, "        0x%08x %8Zu %10a [",
              lt_key->filter_mask, lt_key->nbytes, addr);
        for (u=0; u<bt_udata->mesg.ndims; u++)
            HDfprintf(bt_udata->stream, "%s%Hd", u?", ":"", lt_key->offset[u]);
        HDfputs("]\n", bt_udata->stream);

        /* Use "total storage" information as flag for printing headers */
        bt_udata->total_storage++;
    }

    FUNC_LEAVE_NOAPI(H5B_ITER_CONT);
} /* H5F_istore_iter_dump() */


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_init
 *
 * Purpose:	Initialize the raw data chunk cache for a file.  This is
 *		called when the file handle is initialized.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *              Monday, May 18, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5F_istore_init (H5F_t *f)
{
    H5F_rdcc_t	*rdcc = &(f->shared->rdcc);
    herr_t      ret_value=SUCCEED;       /* Return value */
    
    FUNC_ENTER_NOAPI(H5F_istore_init, FAIL);

    HDmemset (rdcc, 0, sizeof(H5F_rdcc_t));
    if (f->shared->rdcc_nbytes>0 && f->shared->rdcc_nelmts>0) {
	rdcc->nslots = f->shared->rdcc_nelmts;
	rdcc->slot = H5FL_ARR_CALLOC (H5F_rdcc_ent_ptr_t,rdcc->nslots);
	if (NULL==rdcc->slot)
	    HGOTO_ERROR (H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed");
    }

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_flush_entry
 *
 * Purpose:	Writes a chunk to disk.  If RESET is non-zero then the
 *		entry is cleared -- it's slightly faster to flush a chunk if
 *		the RESET flag is turned on because it results in one fewer
 *		memory copy.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *              Thursday, May 21, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5F_istore_flush_entry(H5F_t *f, hid_t dxpl_id, H5F_rdcc_ent_t *ent, hbool_t reset)
{
    herr_t		ret_value=SUCCEED;	/*return value			*/
    H5F_istore_ud1_t 	udata;		/*pass through B-tree		*/
    unsigned		u;		/*counters			*/
    void		*buf=NULL;	/*temporary buffer		*/
    size_t		alloc;		/*bytes allocated for BUF	*/
    hbool_t		point_of_no_return = FALSE;
   
    FUNC_ENTER_NOINIT(H5F_istore_flush_entry);

    assert(f);
    assert(ent);
    assert(!ent->locked);
    HDmemset(&udata, 0, sizeof(H5F_istore_ud1_t));

    buf = ent->chunk;
    if (ent->dirty) {
        udata.mesg = *(ent->layout);
        udata.key.filter_mask = 0;
        udata.addr = HADDR_UNDEF;
        udata.key.nbytes = ent->chunk_size;
        for (u=0; u<ent->layout->ndims; u++) {
            udata.key.offset[u] = ent->offset[u];
        }
        alloc = ent->alloc_size;

        /* Should the chunk be filtered before writing it to disk? */
        if (ent->pline && ent->pline->nfilters) {
            H5P_genplist_t *plist;   /* Data xfer property list */
            H5Z_cb_t            cb_struct;
            H5Z_EDC_t           edc;

            if (!reset) {
                /*
                 * Copy the chunk to a new buffer before running it through
                 * the pipeline because we'll want to save the original buffer
                 * for later.
                 */
                alloc = ent->chunk_size;
                if (NULL==(buf = H5MM_malloc(alloc))) {
                    HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL,
                        "memory allocation failed for pipeline");
                }
                HDmemcpy(buf, ent->chunk, ent->chunk_size);
            } else {
                /*
                 * If we are reseting and something goes wrong after this
                 * point then it's too late to recover because we may have
                 * destroyed the original data by calling H5Z_pipeline().
                 * The only safe option is to continue with the reset
                 * even if we can't write the data to disk.
                 */
                point_of_no_return = TRUE;
                ent->chunk = NULL;
            }
            /* Don't know whether we should involve transfer property list.  So
             * just pass in H5Z_ENABLE_EDC and default callback setting for data 
             * read. */
            if (NULL == (plist = H5P_object_verify(dxpl_id,H5P_DATASET_XFER)))
                HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset transfer property list");
            if(H5P_get(plist,H5D_XFER_EDC_NAME,&edc)<0)
                HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get edc information");
            if(H5P_get(plist,H5D_XFER_FILTER_CB_NAME,&cb_struct)<0)
                HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get filter callback struct");
            if (H5Z_pipeline(f, ent->pline, 0, &(udata.key.filter_mask), edc, 
                             cb_struct, &(udata.key.nbytes), &alloc, &buf)<0) {
                HGOTO_ERROR(H5E_PLINE, H5E_WRITEERROR, FAIL,
                    "output pipeline failed");
            }
        }

        /*
         * Create the chunk it if it doesn't exist, or reallocate the chunk if
         * its size changed.  Then write the data into the file.
         */
        if (H5B_insert(f, dxpl_id, H5B_ISTORE, ent->layout->addr, ent->split_ratios, &udata)<0)
            HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "unable to allocate chunk");
        if (H5F_block_write(f, H5FD_MEM_DRAW, udata.addr, udata.key.nbytes, dxpl_id, buf)<0)
            HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "unable to write raw data to file");

        /* Mark cache entry as clean */
        ent->dirty = FALSE;
        f->shared->rdcc.nflushes++;
    }
    
    /* Reset, but do not free or removed from list */
    if (reset) {
        point_of_no_return = FALSE;
        ent->layout = H5O_free(H5O_LAYOUT_ID, ent->layout);
        ent->pline = H5O_free(H5O_PLINE_ID, ent->pline);
        if (buf==ent->chunk) buf = NULL;
        if(ent->chunk!=NULL)
            ent->chunk = H5MM_xfree(ent->chunk);
    }
    
done:
    /* Free the temp buffer only if it's different than the entry chunk */
    if (buf!=ent->chunk)
        H5MM_xfree(buf);
    
    /*
     * If we reached the point of no return then we have no choice but to
     * reset the entry.  This can only happen if RESET is true but the
     * output pipeline failed.  Do not free the entry or remove it from the
     * list.
     */
    if (ret_value<0 && point_of_no_return) {
        ent->layout = H5O_free(H5O_LAYOUT_ID, ent->layout);
        ent->pline = H5O_free(H5O_PLINE_ID, ent->pline);
        if(ent->chunk)
            ent->chunk = H5MM_xfree(ent->chunk);
    }
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:    H5F_istore_preempt
 *
 * Purpose:     Preempts the specified entry from the cache, flushing it to
 *              disk if necessary.
 *
 * Return:      Non-negative on success/Negative on failure
 *
 * Programmer:  Robb Matzke
 *              Thursday, May 21, 1998
 *
 * Modifications:
 *      Pedro Vicente, March 28, 2002
 *      Added flush parameter that switches the call to H5F_istore_flush_entry 
 *      The call with FALSE is used by the H5F_istore_prune_by_extent function
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5F_istore_preempt(H5F_t *f, hid_t dxpl_id, H5F_rdcc_ent_t * ent, hbool_t flush)
{
    H5F_rdcc_t             *rdcc = &(f->shared->rdcc);
    herr_t      ret_value=SUCCEED;       /* Return value */

    FUNC_ENTER_NOINIT(H5F_istore_preempt);

    assert(f);
    assert(ent);
    assert(!ent->locked);
    assert(ent->idx < rdcc->nslots);

    if(flush) {
	/* Flush */
	if(H5F_istore_flush_entry(f, dxpl_id, ent, TRUE) < 0)
	    HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "cannot flush indexed storage buffer");
    }
    else {
	/* Reset, but do not free or remove from list */
	ent->layout = H5O_free(H5O_LAYOUT_ID, ent->layout);
	ent->pline = H5O_free(H5O_PLINE_ID, ent->pline);
	if(ent->chunk != NULL)
	    ent->chunk = H5MM_xfree(ent->chunk);
    }

    /* Unlink from list */
    if(ent->prev)
	ent->prev->next = ent->next;
    else
	rdcc->head = ent->next;
    if(ent->next)
	ent->next->prev = ent->prev;
    else
	rdcc->tail = ent->prev;
    ent->prev = ent->next = NULL;

    /* Remove from cache */
    rdcc->slot[ent->idx] = NULL;
    ent->idx = UINT_MAX;
    rdcc->nbytes -= ent->chunk_size;
    --rdcc->nused;

    /* Free */
    H5FL_FREE(H5F_rdcc_ent_t, ent);

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_flush
 *
 * Purpose:	Writes all dirty chunks to disk and optionally preempts them
 *		from the cache.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *              Thursday, May 21, 1998
 *
 * Modifications:
 *      Pedro Vicente, March 28, 2002
 *      Added TRUE parameter to the call to H5F_istore_preempt
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5F_istore_flush (H5F_t *f, hid_t dxpl_id, hbool_t preempt)
{
    H5F_rdcc_t		*rdcc = &(f->shared->rdcc);
    int		nerrors=0;
    H5F_rdcc_ent_t	*ent=NULL, *next=NULL;
    herr_t      ret_value=SUCCEED;       /* Return value */
    
    FUNC_ENTER_NOAPI(H5F_istore_flush, FAIL);

    for (ent=rdcc->head; ent; ent=next) {
	next = ent->next;
	if (preempt) {
	    if (H5F_istore_preempt(f, dxpl_id, ent, TRUE )<0)
		nerrors++;
	} else {
	    if (H5F_istore_flush_entry(f, dxpl_id, ent, FALSE)<0)
		nerrors++;
	}
    }
    
    if (nerrors)
	HGOTO_ERROR (H5E_IO, H5E_CANTFLUSH, FAIL, "unable to flush one or more raw data chunks");

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_dest
 *
 * Purpose:	Destroy the entire chunk cache by flushing dirty entries,
 *		preempting all entries, and freeing the cache itself.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *              Thursday, May 21, 1998
 *
 * Modifications:
 *      Pedro Vicente, March 28, 2002
 *      Added TRUE parameter to the call to H5F_istore_preempt
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5F_istore_dest (H5F_t *f, hid_t dxpl_id)
{
    H5F_rdcc_t		*rdcc = &(f->shared->rdcc);
    int		nerrors=0;
    H5F_rdcc_ent_t	*ent=NULL, *next=NULL;
    herr_t      ret_value=SUCCEED;       /* Return value */
    
    FUNC_ENTER_NOAPI(H5F_istore_dest, FAIL);

    for (ent=rdcc->head; ent; ent=next) {
#ifdef H5F_ISTORE_DEBUG
	HDfputc('c', stderr);
	HDfflush(stderr);
#endif
	next = ent->next;
	if (H5F_istore_preempt(f, dxpl_id, ent, TRUE )<0)
	    nerrors++;
    }
    if (nerrors)
	HGOTO_ERROR (H5E_IO, H5E_CANTFLUSH, FAIL, "unable to flush one or more raw data chunks");

    H5FL_ARR_FREE (H5F_rdcc_ent_ptr_t,rdcc->slot);
    HDmemset (rdcc, 0, sizeof(H5F_rdcc_t));

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_prune
 *
 * Purpose:	Prune the cache by preempting some things until the cache has
 *		room for something which is SIZE bytes.  Only unlocked
 *		entries are considered for preemption.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *              Thursday, May 21, 1998
 *
 * Modifications:
 *      Pedro Vicente, March 28, 2002
 *      TRUE parameter to the call to H5F_istore_preempt
 *
 *-------------------------------------------------------------------------
 */
static herr_t
H5F_istore_prune (H5F_t *f, hid_t dxpl_id, size_t size)
{
    int		i, j, nerrors=0;
    H5F_rdcc_t		*rdcc = &(f->shared->rdcc);
    size_t		total = f->shared->rdcc_nbytes;
    const int		nmeth=2;	/*number of methods		*/
    int		        w[1];		/*weighting as an interval	*/
    H5F_rdcc_ent_t	*p[2], *cur;	/*list pointers			*/
    H5F_rdcc_ent_t	*n[2];		/*list next pointers		*/
    herr_t      ret_value=SUCCEED;       /* Return value */

    FUNC_ENTER_NOINIT(H5F_istore_prune);

    /*
     * Preemption is accomplished by having multiple pointers (currently two)
     * slide down the list beginning at the head. Pointer p(N+1) will start
     * traversing the list when pointer pN reaches wN percent of the original
     * list.  In other words, preemption method N gets to consider entries in
     * approximate least recently used order w0 percent before method N+1
     * where 100% means tha method N will run to completion before method N+1
     * begins.  The pointers participating in the list traversal are each
     * given a chance at preemption before any of the pointers are advanced.
     */
    w[0] = (int)(rdcc->nused * f->shared->rdcc_w0);
    p[0] = rdcc->head;
    p[1] = NULL;

    while ((p[0] || p[1]) && rdcc->nbytes+size>total) {

	/* Introduce new pointers */
	for (i=0; i<nmeth-1; i++)
            if (0==w[i])
                p[i+1] = rdcc->head;
	
	/* Compute next value for each pointer */
	for (i=0; i<nmeth; i++)
            n[i] = p[i] ? p[i]->next : NULL;

	/* Give each method a chance */
	for (i=0; i<nmeth && rdcc->nbytes+size>total; i++) {
	    if (0==i && p[0] && !p[0]->locked &&
                    ((0==p[0]->rd_count && 0==p[0]->wr_count) ||
                     (0==p[0]->rd_count && p[0]->chunk_size==p[0]->wr_count) ||
                     (p[0]->chunk_size==p[0]->rd_count && 0==p[0]->wr_count))) {
		/*
		 * Method 0: Preempt entries that have been completely written
		 * and/or completely read but not entries that are partially
		 * written or partially read.
		 */
		cur = p[0];
#ifdef H5F_ISTORE_DEBUG
		HDputc('.', stderr);
		HDfflush(stderr);
#endif
		
	    } else if (1==i && p[1] && !p[1]->locked) {
		/*
		 * Method 1: Preempt the entry without regard to
		 * considerations other than being locked.  This is the last
		 * resort preemption.
		 */
		cur = p[1];
#ifdef H5F_ISTORE_DEBUG
		HDputc(':', stderr);
		HDfflush(stderr);
#endif
		
	    } else {
		/* Nothing to preempt at this point */
		cur= NULL;
	    }

	    if (cur) {
		for (j=0; j<nmeth; j++) {
		    if (p[j]==cur)
                        p[j] = NULL;
		    if (n[j]==cur)
                        n[j] = cur->next;
		}
		if (H5F_istore_preempt(f, dxpl_id, cur, TRUE)<0)
                    nerrors++;
	    }
	}
	
	/* Advance pointers */
	for (i=0; i<nmeth; i++)
            p[i] = n[i];
	for (i=0; i<nmeth-1; i++)
            w[i] -= 1;
    }

    if (nerrors)
	HGOTO_ERROR (H5E_IO, H5E_CANTFLUSH, FAIL, "unable to preempt one or more raw data cache entry");

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_lock
 *
 * Purpose:	Return a pointer to a dataset chunk.  The pointer points
 *		directly into the chunk cache and should not be freed
 *		by the caller but will be valid until it is unlocked.  The
 *		input value IDX_HINT is used to speed up cache lookups and
 *		it's output value should be given to H5F_istore_unlock().
 *		IDX_HINT is ignored if it is out of range, and if it points
 *		to the wrong entry then we fall back to the normal search
 *		method.
 *
 *		If RELAX is non-zero and the chunk isn't in the cache then
 *		don't try to read it from the file, but just allocate an
 *		uninitialized buffer to hold the result.  This is intended
 *		for output functions that are about to overwrite the entire
 *		chunk.
 *
 * Return:	Success:	Ptr to a file chunk.
 *
 *		Failure:	NULL
 *
 * Programmer:	Robb Matzke
 *              Thursday, May 21, 1998
 *
 * Modifications:
 *		Robb Matzke, 1999-08-02
 *		The split ratios are passed in as part of the data transfer
 *		property list.
 *
 *              Pedro Vicente, March 28, 2002
 *              TRUE parameter to the call to H5F_istore_preempt
 *-------------------------------------------------------------------------
 */
static void *
H5F_istore_lock(H5F_t *f, hid_t dxpl_id, const H5O_layout_t *layout,
		const H5O_pline_t *pline, const H5O_fill_t *fill,
		const hssize_t offset[], hbool_t relax,
		unsigned *idx_hint/*in,out*/)
{
    int		idx=0;			/*hash index number	*/
    hsize_t	temp_idx=0;			/* temporary index number	*/
    hbool_t		found = FALSE;		/*already in cache?	*/
    H5F_rdcc_t		*rdcc = &(f->shared->rdcc);/*raw data chunk cache*/
    H5F_rdcc_ent_t	*ent = NULL;		/*cache entry		*/
    unsigned		u;			/*counters		*/
    H5F_istore_ud1_t	udata;			/*B-tree pass-through	*/
    size_t		chunk_size=0;		/*size of a chunk	*/
    hsize_t             tempchunk_size;
    herr_t		status;			/*func return status	*/
    void		*chunk=NULL;		/*the file chunk	*/
    void		*ret_value;	        /*return value		*/
    H5P_genplist_t      *plist;                 /* Property list */
    H5Z_EDC_t           edc;
    H5Z_cb_t            cb_struct;

    FUNC_ENTER_NOINIT(H5F_istore_lock);
    
    assert(TRUE==H5P_isa_class(dxpl_id,H5P_DATASET_XFER));
    plist=H5I_object(dxpl_id);
    assert(plist!=NULL);
    HDmemset(&udata, 0, sizeof(H5F_istore_ud1_t));

    if (rdcc->nslots>0) {
        for (u=0, temp_idx=0; u<layout->ndims; u++) {
            temp_idx += offset[u];
            temp_idx *= layout->dim[u];
        }
        temp_idx += (hsize_t)(layout->addr);
        idx=H5F_HASH(f,temp_idx);
        ent = rdcc->slot[idx];
        
        if (ent && layout->ndims==ent->layout->ndims &&
                H5F_addr_eq(layout->addr, ent->layout->addr)) {
            for (u=0, found=TRUE; u<ent->layout->ndims; u++) {
                if (offset[u]!=ent->offset[u]) {
                    found = FALSE;
                    break;
                }
            }
        }
    }

    if (found) {
        /*
         * Already in the cache.  Count a hit.
         */
        rdcc->nhits++;

    } else if (!found && relax) {
        /*
         * Not in the cache, but we're about to overwrite the whole thing
         * anyway, so just allocate a buffer for it but don't initialize that
         * buffer with the file contents. Count this as a hit instead of a
         * miss because we saved ourselves lots of work.
         */
#ifdef H5F_ISTORE_DEBUG
        HDputc('w', stderr);
        HDfflush(stderr);
#endif
        rdcc->nhits++;
        for (u=0, tempchunk_size=1; u<layout->ndims; u++)
            tempchunk_size *= layout->dim[u];
        H5_ASSIGN_OVERFLOW(chunk_size,tempchunk_size,hsize_t,size_t);
        if (NULL==(chunk=H5MM_malloc (chunk_size)))
            HGOTO_ERROR (H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed for raw data chunk");
        
    } else {

        /*
         * Not in the cache.  Read it from the file and count this as a miss
         * if it's in the file or an init if it isn't.
         */
        for (u=0, tempchunk_size=1; u<layout->ndims; u++) {
            udata.key.offset[u] = offset[u];
            tempchunk_size *= layout->dim[u];
        }
        H5_ASSIGN_OVERFLOW(chunk_size,tempchunk_size,hsize_t,size_t);
        udata.mesg = *layout;
        udata.addr = HADDR_UNDEF;
        status = H5B_find (f, dxpl_id, H5B_ISTORE, layout->addr, &udata);
        H5E_clear ();

        if (status>=0 && H5F_addr_defined(udata.addr)) {
            size_t		chunk_alloc=0;		/*allocated chunk size	*/

            /*
             * The chunk exists on disk.
             */
            /* Chunk size on disk isn't [likely] the same size as the final chunk
             * size in memory, so allocate memory big enough. */
            chunk_alloc = udata.key.nbytes;
            if (NULL==(chunk = H5MM_malloc (chunk_alloc)))
                HGOTO_ERROR (H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed for raw data chunk");
            if (H5F_block_read(f, H5FD_MEM_DRAW, udata.addr, udata.key.nbytes, dxpl_id, chunk)<0)
                HGOTO_ERROR (H5E_IO, H5E_READERROR, NULL, "unable to read raw data chunk");
            if(H5P_get(plist,H5D_XFER_EDC_NAME,&edc)<0)
                HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, NULL, "can't get edc information");
            if(H5P_get(plist,H5D_XFER_FILTER_CB_NAME,&cb_struct)<0)
                HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, NULL, "can't get filter callback struct");
            if (H5Z_pipeline(f, pline, H5Z_FLAG_REVERSE, &(udata.key.filter_mask), edc, 
                     cb_struct, &(udata.key.nbytes), &chunk_alloc, &chunk)<0) {
                HGOTO_ERROR(H5E_PLINE, H5E_READERROR, NULL, "data pipeline read failed");
            }
            rdcc->nmisses++;
        } else {
            /* Chunk size on disk isn't [likely] the same size as the final chunk
             * size in memory, so allocate memory big enough. */
            if (NULL==(chunk = H5MM_malloc (chunk_size)))
                HGOTO_ERROR (H5E_RESOURCE, H5E_NOSPACE, NULL, "memory allocation failed for raw data chunk");
            if (fill && fill->buf) {
                /*
                 * The chunk doesn't exist in the file.  Replicate the fill
                 * value throughout the chunk.
                 */
                assert(0==chunk_size % fill->size);
                H5V_array_fill(chunk, fill->buf, fill->size, chunk_size/fill->size);
            } else {
                /*
                 * The chunk doesn't exist in the file and no fill value was
                 * specified.  Assume all zeros.
                 */
                HDmemset (chunk, 0, chunk_size);
            }
            rdcc->ninits++;
        } /* end else */
    }
    assert (found || chunk_size>0);
    
    if (!found && rdcc->nslots>0 && chunk_size<=f->shared->rdcc_nbytes &&
            (!ent || !ent->locked)) {
        /*
         * Add the chunk to the cache only if the slot is not already locked.
         * Preempt enough things from the cache to make room.
         */
        if (ent) {
#ifdef H5F_ISTORE_DEBUG
            HDputc('#', stderr);
            HDfflush(stderr);
#endif
            if (H5F_istore_preempt(f, dxpl_id, ent, TRUE)<0)
                HGOTO_ERROR(H5E_IO, H5E_CANTINIT, NULL, "unable to preempt chunk from cache");
        }
        if (H5F_istore_prune(f, dxpl_id, chunk_size)<0)
            HGOTO_ERROR(H5E_IO, H5E_CANTINIT, NULL, "unable to preempt chunk(s) from cache");

        /* Create a new entry */
        ent = H5FL_MALLOC(H5F_rdcc_ent_t);
        ent->locked = 0;
        ent->dirty = FALSE;
        ent->chunk_size = chunk_size;
        ent->alloc_size = chunk_size;
        ent->layout = H5O_copy(H5O_LAYOUT_ID, layout, NULL);
        ent->pline = H5O_copy(H5O_PLINE_ID, pline, NULL);
        for (u=0; u<layout->ndims; u++)
            ent->offset[u] = offset[u];
        ent->rd_count = chunk_size;
        ent->wr_count = chunk_size;
        ent->chunk = chunk;
        
        H5P_get(plist,H5D_XFER_BTREE_SPLIT_RATIO_NAME,&(ent->split_ratios));
        
        /* Add it to the cache */
        assert(NULL==rdcc->slot[idx]);
        rdcc->slot[idx] = ent;
        ent->idx = idx;
        rdcc->nbytes += chunk_size;
        rdcc->nused++;

        /* Add it to the linked list */
        ent->next = NULL;
        if (rdcc->tail) {
            rdcc->tail->next = ent;
            ent->prev = rdcc->tail;
            rdcc->tail = ent;
        } else {
            rdcc->head = rdcc->tail = ent;
            ent->prev = NULL;
        }
        found = TRUE;
    } else if (!found) {
        /*
         * The chunk is larger than the entire cache so we don't cache it.
         * This is the reason all those arguments have to be repeated for the
         * unlock function.
         */
        ent = NULL;
        idx = UINT_MAX;

    } else if (found) {
        /*
         * The chunk is not at the beginning of the cache; move it backward
         * by one slot.  This is how we implement the LRU preemption
         * algorithm.
         */
        if (ent->next) {
            if (ent->next->next)
                ent->next->next->prev = ent;
            else
                rdcc->tail = ent;
            ent->next->prev = ent->prev;
            if (ent->prev)
                ent->prev->next = ent->next;
            else
                rdcc->head = ent->next;
            ent->prev = ent->next;
            ent->next = ent->next->next;
            ent->prev->next = ent;
        }
    }

    /* Lock the chunk into the cache */
    if (ent) {
        assert (!ent->locked);
        ent->locked = TRUE;
        chunk = ent->chunk;
    }

    if (idx_hint)
        *idx_hint = idx;

    /* Set return value */
    ret_value = chunk;
    
done:
    if (!ret_value)
        if(chunk)
            H5MM_xfree (chunk);
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_unlock
 *
 * Purpose:	Unlocks a previously locked chunk. The LAYOUT, COMP, and
 *		OFFSET arguments should be the same as for H5F_rdcc_lock().
 *		The DIRTY argument should be set to non-zero if the chunk has
 *		been modified since it was locked. The IDX_HINT argument is
 *		the returned index hint from the lock operation and BUF is
 *		the return value from the lock.
 *
 *		The NACCESSED argument should be the number of bytes accessed
 *		for reading or writing (depending on the value of DIRTY).
 *		It's only purpose is to provide additional information to the
 *		preemption policy.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *              Thursday, May 21, 1998
 *
 * Modifications:
 *		Robb Matzke, 1999-08-02
 *		The split_ratios are passed as part of the data transfer
 *		property list.
 *-------------------------------------------------------------------------
 */
static herr_t
H5F_istore_unlock(H5F_t *f, hid_t dxpl_id, const H5O_layout_t *layout,
		  const H5O_pline_t *pline, hbool_t dirty,
		  const hssize_t offset[], unsigned *idx_hint,
		  uint8_t *chunk, size_t naccessed)
{
    H5F_rdcc_t		*rdcc = &(f->shared->rdcc);
    H5F_rdcc_ent_t	*ent = NULL;
    int		found = -1;
    unsigned		u;
    H5P_genplist_t *plist;      /* Property list */
    
    FUNC_ENTER_NOINIT(H5F_istore_unlock);

    if (UINT_MAX==*idx_hint) {
	/*not in cache*/
    } else {
	assert(*idx_hint<rdcc->nslots);
	assert(rdcc->slot[*idx_hint]);
	assert(rdcc->slot[*idx_hint]->chunk==chunk);
	found = *idx_hint;
    }
    
    if (found<0) {
        /*
         * It's not in the cache, probably because it's too big.  If it's
         * dirty then flush it to disk.  In any case, free the chunk.
         * Note: we have to copy the layout and filter messages so we
         *	 don't discard the `const' qualifier.
         */
        if (dirty) {
            H5F_rdcc_ent_t x;
            hsize_t tempchunk_size;

            HDmemset (&x, 0, sizeof x);
            x.dirty = TRUE;
            x.layout = H5O_copy (H5O_LAYOUT_ID, layout, NULL);
            x.pline = H5O_copy (H5O_PLINE_ID, pline, NULL);
            for (u=0, tempchunk_size=1; u<layout->ndims; u++) {
                x.offset[u] = offset[u];
                tempchunk_size *= layout->dim[u];
            }
            H5_ASSIGN_OVERFLOW(x.chunk_size,tempchunk_size,hsize_t,size_t);
            x.alloc_size = x.chunk_size;
            x.chunk = chunk;

            assert(TRUE==H5P_isa_class(dxpl_id,H5P_DATASET_XFER));
            plist=H5I_object(dxpl_id);
            assert(plist!=NULL);
            H5P_get(plist,H5D_XFER_BTREE_SPLIT_RATIO_NAME,&(x.split_ratios));
            
            H5F_istore_flush_entry (f, dxpl_id, &x, TRUE);
        } else {
            if(chunk)
                H5MM_xfree (chunk);
        }
    } else {
        /*
         * It's in the cache so unlock it.
         */
        ent = rdcc->slot[found];
        assert (ent->locked);
        if (dirty) {
            ent->dirty = TRUE;
            ent->wr_count -= MIN (ent->wr_count, naccessed);
        } else {
            ent->rd_count -= MIN (ent->rd_count, naccessed);
        }
        ent->locked = FALSE;
    }
    
    FUNC_LEAVE_NOAPI(SUCCEED);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_read
 *
 * Purpose:	Reads a multi-dimensional buffer from (part of) an indexed raw
 *		storage array.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *		Wednesday, October 15, 1997
 *
 * Modifications:
 *		Robb Matzke, 1999-08-02
 *		The data transfer property list is passed as an object ID
 *		since that's how the virtual file layer wants it.
 *
 *              Quincey Koziol, 2002-04-02
 *              Enable hyperslab I/O into memory buffer
 *-------------------------------------------------------------------------
 */
herr_t
H5F_istore_read(H5F_t *f, hid_t dxpl_id, const H5O_layout_t *layout,
                H5P_genplist_t *dc_plist,
                const hsize_t size_m[], const hssize_t offset_m[],
		const hssize_t offset_f[], const hsize_t size[], void *buf)
{
    hsize_t		idx_cur[H5O_LAYOUT_NDIMS];
    hsize_t		idx_min[H5O_LAYOUT_NDIMS];
    hsize_t		idx_max[H5O_LAYOUT_NDIMS];
    hsize_t		sub_size[H5O_LAYOUT_NDIMS];
    hssize_t		offset_wrt_chunk[H5O_LAYOUT_NDIMS];
    hssize_t		sub_offset_m[H5O_LAYOUT_NDIMS];
    hssize_t		chunk_offset[H5O_LAYOUT_NDIMS];
    int		i, carry;
    unsigned		u;
    hsize_t		naccessed;		/*bytes accessed in chnk*/
    uint8_t		*chunk=NULL;		/*ptr to a chunk buffer	*/
    unsigned		idx_hint=0;		/*cache index hint	*/
    hsize_t		chunk_size;     /* Bytes in chunk */
    haddr_t	        chunk_addr;     /* Chunk address on disk */
    H5O_pline_t         pline;          /* I/O pipeline information */
    H5O_fill_t          fill;           /* Fill value information */
    herr_t              ret_value = SUCCEED;            /* Return value */

    FUNC_ENTER_NOAPI(H5F_istore_read, FAIL);

    /* Check args */
    assert(f);
    assert(layout && H5D_CHUNKED==layout->type);
    assert(layout->ndims>0 && layout->ndims<=H5O_LAYOUT_NDIMS);
    assert(H5F_addr_defined(layout->addr));
    assert(size_m);
    assert(offset_m);
    assert(offset_f);
    assert(size);
    assert(buf);

    /* Get necessary properties from property list */
    if(H5P_get(dc_plist, H5D_CRT_FILL_VALUE_NAME, &fill) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get fill value");
    if(H5P_get(dc_plist, H5D_CRT_DATA_PIPELINE_NAME, &pline) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get data pipeline");

    /* Compute chunk size */
    for (u=0, chunk_size=1; u<layout->ndims; u++)
        chunk_size *= layout->dim[u];
    
#ifndef NDEBUG
    for (u=0; u<layout->ndims; u++) {
        assert(offset_f[u]>=0); /*negative offsets not supported*/
        assert(offset_m[u]>=0); /*negative offsets not supported*/
        assert(size[u]<SIZET_MAX);
        assert(offset_m[u]+(hssize_t)size[u]<=(hssize_t)size_m[u]);
        assert(layout->dim[u]>0);
    }
#endif

    /*
     * Set up multi-dimensional counters (idx_min, idx_max, and idx_cur) and
     * loop through the chunks copying each to its final destination in the
     * application buffer.
     */
    for (u=0; u<layout->ndims; u++) {
        idx_min[u] = offset_f[u] / layout->dim[u];
        idx_max[u] = (offset_f[u]+size[u]-1) / layout->dim[u] + 1;
        idx_cur[u] = idx_min[u];
    }

    /* Loop over all chunks */
    carry=0;
    while (carry==0) {
        for (u=0, naccessed=1; u<layout->ndims; u++) {
            /* The location and size of the chunk being accessed */
            assert(layout->dim[u] < HSSIZET_MAX);
            chunk_offset[u] = idx_cur[u] * (hssize_t)(layout->dim[u]);

            /* The offset and size wrt the chunk */
            offset_wrt_chunk[u] = MAX(offset_f[u], chunk_offset[u]) -
                      chunk_offset[u];
            sub_size[u] = MIN((idx_cur[u]+1)*layout->dim[u],
                      offset_f[u]+size[u]) -
                  (chunk_offset[u] + offset_wrt_chunk[u]);
            naccessed *= sub_size[u];
            
            /* Offset into mem buffer */
            sub_offset_m[u] = chunk_offset[u] + offset_wrt_chunk[u] +
                      offset_m[u] - offset_f[u];
        }

        /* Get the address of this chunk on disk */
        chunk_addr=H5F_istore_get_addr(f, dxpl_id, layout, chunk_offset);

        /*
         * If the chunk is too large to load into the cache and it has no
         * filters in the pipeline (i.e. not compressed) and if the address
         * for the chunk has been defined, then don't load the chunk into the
         * cache, just read the data from it directly.
         */
        if ((chunk_size>f->shared->rdcc_nbytes && pline.nfilters==0 &&
                chunk_addr!=HADDR_UNDEF)

        /*
         * If MPIO or MPIPOSIX is used and file can be written to, we must bypass the
         * chunk-cache scheme because other MPI processes could be writing to
         * other elements in the same chunk.
         * Do a direct write-through of only the elements requested.
         */
            || ((IS_H5FD_MPIO(f) ||IS_H5FD_MPIPOSIX(f)) && (H5F_ACC_RDWR & f->shared->flags))
            ) {
            H5O_layout_t	l;	/* temporary layout */

#ifdef H5_HAVE_PARALLEL
            /* Additional sanity checks when operating in parallel */
            if (chunk_addr==HADDR_UNDEF || pline.nfilters>0)
                HGOTO_ERROR (H5E_IO, H5E_WRITEERROR, FAIL, "unable to locate raw data chunk");
#endif /* H5_HAVE_PARALLEL */
            
            /*
             * use default transfer mode as we do not support collective
             * transfer mode since each data write could decompose into
             * multiple chunk writes and we are not doing the calculation yet.
             */
            l.type = H5D_CONTIGUOUS;
            l.ndims = layout->ndims;
            for (u=l.ndims; u-- > 0; /*void*/)
                l.dim[u] = layout->dim[u];
            l.addr = chunk_addr;
            if (H5F_arr_read(f, dxpl_id, &l, dc_plist, sub_size, size_m, sub_offset_m, offset_wrt_chunk, buf)<0)
                HGOTO_ERROR (H5E_IO, H5E_READERROR, FAIL, "unable to read raw data from file");
        } /* end if */
        else {
            /*
             * Lock the chunk, transfer data to the application, then unlock
             * the chunk.
             */
            if (NULL==(chunk=H5F_istore_lock(f, dxpl_id, layout, &pline, &fill,
                         chunk_offset, FALSE, &idx_hint)))
                HGOTO_ERROR(H5E_IO, H5E_READERROR, FAIL, "unable to read raw data chunk");
            H5V_hyper_copy(layout->ndims, sub_size, size_m, sub_offset_m,
                   (void*)buf, layout->dim, offset_wrt_chunk, chunk);
            H5_CHECK_OVERFLOW(naccessed,hsize_t,size_t);
            if (H5F_istore_unlock(f, dxpl_id, layout, &pline, FALSE,
                      chunk_offset, &idx_hint, chunk, (size_t)naccessed)<0)
                HGOTO_ERROR(H5E_IO, H5E_READERROR, FAIL, "unable to unlock raw data chunk");
        } /* end else */

        /* Increment indices */
        for (i=(int)(layout->ndims-1), carry=1; i>=0 && carry; --i) {
            if (++idx_cur[i]>=idx_max[i])
                idx_cur[i] = idx_min[i];
            else
                carry = 0;
        }
    }

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_write
 *
 * Purpose:	Writes a multi-dimensional buffer to (part of) an indexed raw
 *		storage array.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *		Wednesday, October 15, 1997
 *
 * Modifications:
 *		Robb Matzke, 1999-08-02
 *		The data transfer property list is passed as an object ID
 *		since that's how the virtual file layer wants it.
 *
 *              Quincey Koziol, 2002-04-02
 *              Enable hyperslab I/O into memory buffer
 *-------------------------------------------------------------------------
 */
herr_t
H5F_istore_write(H5F_t *f, hid_t dxpl_id, const H5O_layout_t *layout,
                 H5P_genplist_t *dc_plist,
                 const hsize_t size_m[], const hssize_t offset_m[],
		 const hssize_t offset_f[], const hsize_t size[],
		 const void *buf)
{
    int		i, carry;
    unsigned		u;
    hsize_t		idx_cur[H5O_LAYOUT_NDIMS];
    hsize_t		idx_min[H5O_LAYOUT_NDIMS];
    hsize_t		idx_max[H5O_LAYOUT_NDIMS];
    hsize_t		sub_size[H5O_LAYOUT_NDIMS];
    hssize_t	chunk_offset[H5O_LAYOUT_NDIMS];
    hssize_t	offset_wrt_chunk[H5O_LAYOUT_NDIMS];
    hssize_t	sub_offset_m[H5O_LAYOUT_NDIMS];
    uint8_t		*chunk=NULL;
    unsigned		idx_hint=0;
    hsize_t		chunk_size, naccessed;
    haddr_t	        chunk_addr;     /* Chunk address on disk */
    H5O_pline_t         pline;          /* I/O pipeline information */
    H5O_fill_t          fill;           /* Fill value information */
    herr_t              ret_value = SUCCEED;            /* Return value */
    
    FUNC_ENTER_NOAPI(H5F_istore_write, FAIL);

    /* Check args */
    assert(f);
    assert(layout && H5D_CHUNKED==layout->type);
    assert(layout->ndims>0 && layout->ndims<=H5O_LAYOUT_NDIMS);
    assert(H5F_addr_defined(layout->addr));
    assert(size_m);
    assert(offset_m);
    assert(offset_f);
    assert(size);
    assert(buf);

    /* Get necessary properties from property list */
    if(H5P_get(dc_plist, H5D_CRT_FILL_VALUE_NAME, &fill) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get fill value");
    if(H5P_get(dc_plist, H5D_CRT_DATA_PIPELINE_NAME, &pline) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get data pipeline");

    /* Compute chunk size */
    for (u=0, chunk_size=1; u<layout->ndims; u++)
        chunk_size *= layout->dim[u];

#ifndef NDEBUG
    for (u=0; u<layout->ndims; u++) {
        assert(offset_f[u]>=0); /*negative offsets not supported*/
        assert(offset_m[u]>=0); /*negative offsets not supported*/
        assert(size[u]<SIZET_MAX);
        assert(offset_m[u]+(hssize_t)size[u]<=(hssize_t)size_m[u]);
        assert(layout->dim[u]>0);
    }
#endif

    /*
     * Set up multi-dimensional counters (idx_min, idx_max, and idx_cur) and
     * loop through the chunks copying each chunk from the application to the
     * chunk cache.
     */
    for (u=0; u<layout->ndims; u++) {
        idx_min[u] = offset_f[u] / layout->dim[u];
        idx_max[u] = (offset_f[u]+size[u]-1) / layout->dim[u] + 1;
        idx_cur[u] = idx_min[u];
    }


    /* Loop over all chunks */
    carry=0;
    while (carry==0) {
        for (u=0, naccessed=1; u<layout->ndims; u++) {
            /* The location and size of the chunk being accessed */
            assert(layout->dim[u] < HSSIZET_MAX);
            chunk_offset[u] = idx_cur[u] * (hssize_t)(layout->dim[u]);

            /* The offset and size wrt the chunk */
            offset_wrt_chunk[u] = MAX(offset_f[u], chunk_offset[u]) -
                      chunk_offset[u];
            sub_size[u] = MIN((idx_cur[u]+1)*layout->dim[u],
                      offset_f[u]+size[u]) -
                  (chunk_offset[u] + offset_wrt_chunk[u]);
            naccessed *= sub_size[u];

            /* Offset into mem buffer */
            sub_offset_m[u] = chunk_offset[u] + offset_wrt_chunk[u] +
                      offset_m[u] - offset_f[u];
        }

        /* Get the address of this chunk on disk */
        chunk_addr=H5F_istore_get_addr(f, dxpl_id, layout, chunk_offset);

        /*
         * If the chunk is too large to load into the cache and it has no
         * filters in the pipeline (i.e. not compressed) and if the address
         * for the chunk has been defined, then don't load the chunk into the
         * cache, just write the data to it directly.
         */
        if ((chunk_size>f->shared->rdcc_nbytes && pline.nfilters==0 &&
                chunk_addr!=HADDR_UNDEF)

        /*
         * If MPIO or MPIPOSIX is used, must bypass the chunk-cache scheme because other
         * MPI processes could be writing to other elements in the same chunk.
         * Do a direct write-through of only the elements requested.
         */
            || ((IS_H5FD_MPIO(f) ||IS_H5FD_MPIPOSIX(f)) && (H5F_ACC_RDWR & f->shared->flags))
            ) {
            H5O_layout_t	l;	/* temporary layout */

#ifdef H5_HAVE_PARALLEL
            /* Additional sanity check when operating in parallel */
            if (chunk_addr==HADDR_UNDEF || pline.nfilters>0) {
                HGOTO_ERROR (H5E_IO, H5E_WRITEERROR, FAIL, "unable to locate raw data chunk");
            }
#endif /* H5_HAVE_PARALLEL */
            
            /*
             * use default transfer mode as we do not support collective
             * transfer mode since each data write could decompose into
             * multiple chunk writes and we are not doing the calculation yet.
             */
            l.type = H5D_CONTIGUOUS;
            l.ndims = layout->ndims;
            for (u=l.ndims; u-- > 0; /*void*/)
                l.dim[u] = layout->dim[u];
            l.addr = chunk_addr;
            if (H5F_arr_write(f, dxpl_id, &l, dc_plist, sub_size, size_m, sub_offset_m, offset_wrt_chunk, buf)<0)
                HGOTO_ERROR (H5E_IO, H5E_WRITEERROR, FAIL, "unable to write raw data to file");
        } /* end if */
        else {
            /*
             * Lock the chunk, copy from application to chunk, then unlock the
             * chunk.
             */
            if (NULL==(chunk=H5F_istore_lock(f, dxpl_id, layout, &pline, &fill,
                     chunk_offset, (hbool_t)(naccessed==chunk_size), &idx_hint)))
                HGOTO_ERROR (H5E_IO, H5E_WRITEERROR, FAIL, "unable to read raw data chunk");
            H5V_hyper_copy(layout->ndims, sub_size,
               layout->dim, offset_wrt_chunk, chunk, size_m, sub_offset_m, buf);
            H5_CHECK_OVERFLOW(naccessed,hsize_t,size_t);
            if (H5F_istore_unlock(f, dxpl_id, layout, &pline, TRUE,
                      chunk_offset, &idx_hint, chunk, (size_t)naccessed)<0)
                HGOTO_ERROR (H5E_IO, H5E_WRITEERROR, FAIL, "uanble to unlock raw data chunk");
        } /* end else */
        
        /* Increment indices */
        for (i=layout->ndims-1, carry=1; i>=0 && carry; --i) {
            if (++idx_cur[i]>=idx_max[i])
                idx_cur[i] = idx_min[i];
            else
                carry = 0;
        }
    } /* end while */

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_create
 *
 * Purpose:	Creates a new indexed-storage B-tree and initializes the
 *		istore struct with information about the storage.  The
 *		struct should be immediately written to the object header.
 *
 *		This function must be called before passing ISTORE to any of
 *		the other indexed storage functions!
 *
 * Return:	Non-negative on success (with the ISTORE argument initialized
 *		and ready to write to an object header). Negative on failure.
 *
 * Programmer:	Robb Matzke
 *		Tuesday, October 21, 1997
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5F_istore_create(H5F_t *f, hid_t dxpl_id, H5O_layout_t *layout /*out */ )
{
    H5F_istore_ud1_t	udata;
#ifndef NDEBUG
    unsigned			u;
#endif
    herr_t      ret_value=SUCCEED;       /* Return value */

    FUNC_ENTER_NOAPI(H5F_istore_create, FAIL);

    /* Check args */
    assert(f);
    assert(layout && H5D_CHUNKED == layout->type);
    assert(layout->ndims > 0 && layout->ndims <= H5O_LAYOUT_NDIMS);
#ifndef NDEBUG
    for (u = 0; u < layout->ndims; u++)
	assert(layout->dim[u] > 0);
#endif

    udata.mesg.ndims = layout->ndims;
    if (H5B_create(f, dxpl_id, H5B_ISTORE, &udata, &(layout->addr)/*out*/) < 0)
	HGOTO_ERROR(H5E_IO, H5E_CANTINIT, FAIL, "can't create B-tree");
    
done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_allocated
 *
 * Purpose:	Return the number of bytes allocated in the file for storage
 *		of raw data under the specified B-tree (ADDR is the address
 *		of the B-tree).
 *
 * Return:	Success:	Number of bytes stored in all chunks.
 *
 *		Failure:	0
 *
 * Programmer:	Robb Matzke
 *              Wednesday, April 21, 1999
 *
 * Modifications:
 *		Robb Matzke, 1999-07-28
 *		The ADDR argument is passed by value.
 *-------------------------------------------------------------------------
 */
hsize_t
H5F_istore_allocated(H5F_t *f, hid_t dxpl_id, unsigned ndims, haddr_t addr)
{
    H5F_istore_ud1_t	udata;
    hsize_t      ret_value;       /* Return value */

    FUNC_ENTER_NOAPI(H5F_istore_nchunks, 0);

    HDmemset(&udata, 0, sizeof udata);
    udata.mesg.ndims = ndims;
    if (H5B_iterate(f, dxpl_id, H5B_ISTORE, H5F_istore_iter_allocated, addr, &udata)<0)
        HGOTO_ERROR(H5E_IO, H5E_CANTINIT, 0, "unable to iterate over chunk B-tree");

    /* Set return value */
    ret_value=udata.total_storage;

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_dump_btree
 *
 * Purpose:	Prints information about the storage B-tree to the specified
 *		stream.
 *
 * Return:	Success:	Non-negative
 *
 *		Failure:	negative
 *
 * Programmer:	Robb Matzke
 *              Wednesday, April 28, 1999
 *
 * Modifications:
 *		Robb Matzke, 1999-07-28
 *		The ADDR argument is passed by value.
 *-------------------------------------------------------------------------
 */
herr_t
H5F_istore_dump_btree(H5F_t *f, hid_t dxpl_id, FILE *stream, unsigned ndims, haddr_t addr)
{
    H5F_istore_ud1_t	udata;
    herr_t      ret_value=SUCCEED;       /* Return value */

    FUNC_ENTER_NOAPI(H5F_istore_dump_btree, FAIL);

    HDmemset(&udata, 0, sizeof udata);
    udata.mesg.ndims = ndims;
    udata.stream = stream;
    if(stream)
        HDfprintf(stream, "    Address: %a\n",addr);
    if(H5B_iterate(f, dxpl_id, H5B_ISTORE, H5F_istore_iter_dump, addr, &udata)<0)
        HGOTO_ERROR(H5E_IO, H5E_CANTINIT, 0, "unable to iterate over chunk B-tree");

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_stats
 *
 * Purpose:	Print raw data cache statistics to the debug stream.  If
 *		HEADERS is non-zero then print table column headers,
 *		otherwise assume that the H5AC layer has already printed them.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *              Thursday, May 21, 1998
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5F_istore_stats (H5F_t *f, hbool_t headers)
{
    H5F_rdcc_t	*rdcc = &(f->shared->rdcc);
    double	miss_rate;
    char	ascii[32];
    herr_t      ret_value=SUCCEED;       /* Return value */
    
    FUNC_ENTER_NOAPI(H5F_istore_stats, FAIL);

    if (!H5DEBUG(AC))
        HGOTO_DONE(SUCCEED);

    if (headers) {
        fprintf(H5DEBUG(AC), "H5F: raw data cache statistics for file %s\n",
            f->name);
        fprintf(H5DEBUG(AC), "   %-18s %8s %8s %8s %8s+%-8s\n",
            "Layer", "Hits", "Misses", "MissRate", "Inits", "Flushes");
        fprintf(H5DEBUG(AC), "   %-18s %8s %8s %8s %8s-%-8s\n",
            "-----", "----", "------", "--------", "-----", "-------");
    }

#ifdef H5AC_DEBUG
    if (H5DEBUG(AC)) headers = TRUE;
#endif

    if (headers) {
        if (rdcc->nhits>0 || rdcc->nmisses>0) {
            miss_rate = 100.0 * rdcc->nmisses /
                    (rdcc->nhits + rdcc->nmisses);
        } else {
            miss_rate = 0.0;
        }
        if (miss_rate > 100) {
            sprintf(ascii, "%7d%%", (int) (miss_rate + 0.5));
        } else {
            sprintf(ascii, "%7.2f%%", miss_rate);
        }

        fprintf(H5DEBUG(AC), "   %-18s %8u %8u %7s %8d+%-9ld\n",
            "raw data chunks", rdcc->nhits, rdcc->nmisses, ascii,
            rdcc->ninits, (long)(rdcc->nflushes)-(long)(rdcc->ninits));
    }

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_debug
 *
 * Purpose:	Debugs a B-tree node for indexed raw data storage.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Robb Matzke
 *              Thursday, April 16, 1998
 *
 * Modifications:
 *		Robb Matzke, 1999-07-28
 *		The ADDR argument is passed by value.
 *-------------------------------------------------------------------------
 */
herr_t
H5F_istore_debug(H5F_t *f, hid_t dxpl_id, haddr_t addr, FILE * stream, int indent,
		 int fwidth, int ndims)
{
    H5F_istore_ud1_t	udata;
    herr_t ret_value=SUCCEED;   /* Return value */
    
    FUNC_ENTER_NOAPI(H5F_istore_debug, FAIL);

    HDmemset (&udata, 0, sizeof udata);
    udata.mesg.ndims = ndims;

    H5B_debug (f, dxpl_id, addr, stream, indent, fwidth, H5B_ISTORE, &udata);

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_get_addr
 *
 * Purpose:	Get the file address of a chunk if file space has been
 *		assigned.  Save the retrieved information in the udata
 *		supplied.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Programmer:	Albert Cheng
 *              June 27, 1998
 *
 * Modifications:
 *              Modified to return the address instead of returning it through
 *              a parameter - QAK, 1/30/02
 *
 *-------------------------------------------------------------------------
 */
static haddr_t
H5F_istore_get_addr(H5F_t *f, hid_t dxpl_id, const H5O_layout_t *layout,
		    const hssize_t offset[])
{
    H5F_istore_ud1_t	udata;                  /* Information about a chunk */
    unsigned	u;
    haddr_t	ret_value;		/* Return value */
    
    FUNC_ENTER_NOINIT(H5F_istore_get_addr);

    assert(f);
    assert(layout && (layout->ndims > 0));
    assert(offset);

    /* Initialize the information about the chunk we are looking for */
    for (u=0; u<layout->ndims; u++)
	udata.key.offset[u] = offset[u];
    udata.mesg = *layout;
    udata.addr = HADDR_UNDEF;

    /* Go get the chunk information */
    if (H5B_find (f, dxpl_id, H5B_ISTORE, layout->addr, &udata)<0) {
        H5E_clear();
	HGOTO_ERROR(H5E_BTREE,H5E_NOTFOUND,HADDR_UNDEF,"Can't locate chunk info");
    } /* end if */

    /* Success!  Set the return value */
    ret_value=udata.addr;

done:
    FUNC_LEAVE_NOAPI(ret_value);
} /* H5F_istore_get_addr() */


/*-------------------------------------------------------------------------
 * Function:	H5F_istore_allocate
 *
 * Purpose:	Allocate file space for all chunks that are not allocated yet.
 *		Return SUCCEED if all needed allocation succeed, otherwise
 *		FAIL.
 *
 * Return:	Non-negative on success/Negative on failure
 *
 * Note:	Current implementation relies on cache_size being 0,
 *		thus no chunk is cashed and written to disk immediately
 *		when a chunk is unlocked (via H5F_istore_unlock)
 *		This should be changed to do a direct flush independent
 *		of the cache value.
 *
 * Programmer:	Albert Cheng
 *		June 26, 1998
 *
 * Modifications:
 *		rky, 1998-09-23
 *		Added barrier to preclude racing with data writes.
 *
 *		rky, 1998-12-07
 *		Added Wait-Signal wrapper around unlock-lock critical region
 *		to prevent race condition (unlock reads, lock writes the
 *		chunk).
 *
 * 		Robb Matzke, 1999-08-02
 *		The split_ratios are passed in as part of the data transfer
 *		property list.
 *
 * 		Quincey Koziol, 2002-05-16
 *		Rewrote algorithm to allocate & write blocks without using
 *              lock/unlock code.
 *
 * 		Quincey Koziol, 2002-05-17
 *		Added feature to avoid writing fill-values if user has indicated
 *              that they should never be written.
 *-------------------------------------------------------------------------
 */
herr_t
H5F_istore_allocate(H5F_t *f, hid_t dxpl_id, const H5O_layout_t *layout,
        const hsize_t *space_dim, H5P_genplist_t *dc_plist, hbool_t full_overwrite)
{
    hssize_t	chunk_offset[H5O_LAYOUT_NDIMS]; /* Offset of current chunk */
    hsize_t	chunk_size;     /* Size of chunk in bytes */
    H5O_pline_t pline;          /* I/O pipeline information */
    H5O_fill_t fill;            /* Fill value information */
    H5D_fill_time_t fill_time;  /* When to write fill values */
    H5F_istore_ud1_t udata;	/* B-tree pass-through for creating chunk */
    void *chunk=NULL;           /* Chunk buffer for writing fill values */
    H5P_genplist_t *dx_plist;   /* Data xfer property list */
    double	split_ratios[3];/* B-tree node splitting ratios		*/
#ifdef H5_HAVE_PARALLEL
    MPI_Comm	mpi_comm=MPI_COMM_NULL;	/* MPI communicator for file */
    int         mpi_rank=(-1);  /* This process's rank  */
    int         mpi_size=(-1);  /* Total # of processes */
    int         mpi_round=0;    /* Current process responsible for I/O */
    int         mpi_code;       /* MPI return code */
    unsigned    blocks_written=0; /* Flag to indicate that chunk was actually written */
    unsigned    using_mpi=0;    /* Flag to indicate that the file is being accessed with an MPI-capable file driver */
#endif /* H5_HAVE_PARALLEL */
    int		carry;          /* Flag to indicate that chunk increment carrys to higher dimension (sorta) */
    unsigned	chunk_exists;   /* Flag to indicate whether a chunk exists already */
    int		i;              /* Local index variable */
    unsigned	u;              /* Local index variable */
    H5Z_EDC_t   edc;            /* Decide whether to enable EDC for read */
    H5Z_cb_t    cb_struct;
    herr_t	ret_value=SUCCEED;	/* Return value */
    
    FUNC_ENTER_NOAPI(H5F_istore_allocate, FAIL);

    /* Check args */
    assert(f);
    assert(space_dim);
    assert(layout && H5D_CHUNKED==layout->type);
    assert(layout->ndims>0 && layout->ndims<=H5O_LAYOUT_NDIMS);
    assert(H5F_addr_defined(layout->addr));
    assert(TRUE==H5P_isa_class(dxpl_id,H5P_DATASET_XFER));
    assert(dc_plist!=NULL);

    /* Get necessary properties from dataset creation property list */
    if(H5P_get(dc_plist, H5D_CRT_FILL_VALUE_NAME, &fill) < 0)
        HGOTO_ERROR(H5E_STORAGE, H5E_CANTGET, FAIL, "can't get fill value");
    if(H5P_get(dc_plist, H5D_CRT_DATA_PIPELINE_NAME, &pline) < 0)
        HGOTO_ERROR(H5E_STORAGE, H5E_CANTGET, FAIL, "can't get data pipeline");
    if(H5P_get(dc_plist, H5D_CRT_FILL_TIME_NAME, &fill_time) < 0)
        HGOTO_ERROR(H5E_PLIST, H5E_CANTGET, FAIL, "can't retrieve fill time");

    /* Get necessary properties from dataset transfer property list */
    if (NULL == (dx_plist = H5P_object_verify(dxpl_id,H5P_DATASET_XFER)))
        HGOTO_ERROR(H5E_ARGS, H5E_BADTYPE, FAIL, "not a dataset transfer property list");
    if(H5P_get(dx_plist,H5D_XFER_BTREE_SPLIT_RATIO_NAME,split_ratios)<0)
        HGOTO_ERROR(H5E_STORAGE, H5E_CANTGET, FAIL, "can't get B-tree split ratios");
    if(H5P_get(dx_plist,H5D_XFER_EDC_NAME,&edc)<0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get edc information");
    if(H5P_get(dx_plist,H5D_XFER_FILTER_CB_NAME,&cb_struct)<0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get filter callback struct");

#ifdef H5_HAVE_PARALLEL
    /* Retrieve up MPI parameters */
    if(IS_H5FD_MPIO(f)) {
        /* Get the MPI communicator */
        if (MPI_COMM_NULL == (mpi_comm=H5FD_mpio_communicator(f->shared->lf)))
            HGOTO_ERROR(H5E_INTERNAL, H5E_MPI, FAIL, "Can't retrieve MPI communicator");

        /* Get the MPI rank & size */
        if ((mpi_rank=H5FD_mpio_mpi_rank(f->shared->lf))<0)
            HGOTO_ERROR(H5E_INTERNAL, H5E_MPI, FAIL, "Can't retrieve MPI rank");
        if ((mpi_size=H5FD_mpio_mpi_size(f->shared->lf))<0)
            HGOTO_ERROR(H5E_INTERNAL, H5E_MPI, FAIL, "Can't retrieve MPI size");

        /* Set the MPI-capable file driver flag */
        using_mpi=1;
    } /* end if */
    else if(IS_H5FD_MPIPOSIX(f)) {
        /* Get the MPI communicator */
        if (MPI_COMM_NULL == (mpi_comm=H5FD_mpiposix_communicator(f->shared->lf)))
            HGOTO_ERROR(H5E_INTERNAL, H5E_MPI, FAIL, "Can't retrieve MPI communicator");

        /* Get the MPI rank & size */
        if ((mpi_rank=H5FD_mpiposix_mpi_rank(f->shared->lf))<0)
            HGOTO_ERROR(H5E_INTERNAL, H5E_MPI, FAIL, "Can't retrieve MPI rank");
        if ((mpi_size=H5FD_mpiposix_mpi_size(f->shared->lf))<0)
            HGOTO_ERROR(H5E_INTERNAL, H5E_MPI, FAIL, "Can't retrieve MPI size");

        /* Set the MPI-capable file driver flag */
        using_mpi=1;
    } /* end else */
#ifdef H5_HAVE_FPHDF5
    else if (IS_H5FD_FPHDF5(f)) {
        /* Get the FPHDF5 barrier communicator */
        if (MPI_COMM_NULL == (mpi_comm = H5FD_fphdf5_barrier_communicator(f->shared->lf)))
            HGOTO_ERROR(H5E_INTERNAL, H5E_MPI, FAIL, "Can't retrieve MPI communicator");

        /* Get the MPI rank & size */
        if ((mpi_rank = H5FD_fphdf5_mpi_rank(f->shared->lf)) < 0)
            HGOTO_ERROR(H5E_INTERNAL, H5E_MPI, FAIL, "Can't retrieve MPI rank");

        if ((mpi_size = H5FD_fphdf5_mpi_size(f->shared->lf)) < 0)
            HGOTO_ERROR(H5E_INTERNAL, H5E_MPI, FAIL, "Can't retrieve MPI size");

        /* Set the MPI-capable file driver flag */
        using_mpi = 1;
    } /* end if */
#endif  /* H5_HAVE_FPHDF5 */
#endif  /* H5_HAVE_PARALLEL */

    /*
     * Setup indice to go through all chunks. (Future improvement
     * should allocate only chunks that have no file space assigned yet.
     */
    for (u=0, chunk_size=1; u<layout->ndims; u++) {
        chunk_offset[u] = 0;
        chunk_size *= layout->dim[u];
    } /* end for */

    /* Check if fill values should be written to blocks */
    if(fill_time != H5D_FILL_TIME_NEVER && !full_overwrite) {
        /* Allocate chunk buffer for processes to use when writing fill values */
        H5_CHECK_OVERFLOW(chunk_size,hsize_t,size_t);
        if (NULL==(chunk = H5MM_malloc((size_t)chunk_size)))
            HGOTO_ERROR(H5E_RESOURCE, H5E_NOSPACE, FAIL, "memory allocation failed for chunk");

        /* Fill the chunk with the proper values */
        if(fill.buf) {
            /*
             * Replicate the fill value throughout the chunk.
             */
            assert(0==chunk_size % fill.size);
            H5V_array_fill(chunk, fill.buf, fill.size, (size_t)chunk_size/fill.size);
        } else {
            /*
             * No fill value was specified, assume all zeros.
             */
            HDmemset (chunk, 0, (size_t)chunk_size);
        } /* end else */

        /* Check if there are filters which need to be applied to the chunk */
        if (pline.nfilters>0) {
            unsigned filter_mask=0;
            size_t buf_size=(size_t)chunk_size;
            size_t nbytes=(size_t)chunk_size;

            /* Push the chunk through the filters */
            if (H5Z_pipeline(f, &pline, 0, &filter_mask, edc, cb_struct, &nbytes, &buf_size, &chunk)<0)
                HGOTO_ERROR(H5E_PLINE, H5E_WRITEERROR, FAIL, "output pipeline failed");

            /* Keep the number of bytes the chunk turned in to */
            chunk_size=nbytes;
        } /* end if */
    } /* end if */

    /* Loop over all chunks */
    carry=0;
    while (carry==0) {
        /* Check if the chunk exists yet on disk */
        chunk_exists=1;
        if(H5F_istore_get_addr(f,dxpl_id,layout,chunk_offset)==HADDR_UNDEF) {
            H5F_rdcc_t             *rdcc = &(f->shared->rdcc);	/*raw data chunk cache */
            H5F_rdcc_ent_t         *ent = NULL;              	/*cache entry  */

            /* Didn't find the chunk on disk */
            chunk_exists = 0;

            /* Look for chunk in cache */
            for(ent = rdcc->head; ent && !chunk_exists; ent = ent->next) {
                /* Make certain we are dealing with the correct B-tree, etc */
                if (layout->ndims==ent->layout->ndims &&
                        H5F_addr_eq(layout->addr, ent->layout->addr)) {

                    /* Assume a match */
                    chunk_exists = 1;
                    for(u = 0; u < layout->ndims && chunk_exists; u++) {
                        if(ent->offset[u] != chunk_offset[u])
                            chunk_exists = 0;       /* Reset if no match */
                    } /* end for */
                } /* end if */
            } /* end for */
        } /* end if */

        if(!chunk_exists) {
            /* Initialize the chunk information */
            udata.mesg = *layout;
            udata.key.filter_mask = 0;
            udata.addr = HADDR_UNDEF;
            H5_CHECK_OVERFLOW(chunk_size,hsize_t,size_t);
            udata.key.nbytes = (size_t)chunk_size;
            for (u=0; u<layout->ndims; u++)
                udata.key.offset[u] = chunk_offset[u];

            /* Allocate the chunk with all processes */
            if (H5B_insert(f, dxpl_id, H5B_ISTORE, layout->addr, split_ratios, &udata)<0)
                HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "unable to allocate chunk");

            /* Check if fill values should be written to blocks */
            if(fill_time != H5D_FILL_TIME_NEVER && !full_overwrite) {
#ifdef H5_HAVE_PARALLEL
                /* Check if this file is accessed with an MPI-capable file driver */
                if(using_mpi) {
                    /* Round-robin write the chunks out from only one process */
                    if(mpi_round==mpi_rank) {
                        if (H5F_block_write(f, H5FD_MEM_DRAW, udata.addr, udata.key.nbytes, dxpl_id, chunk)<0)
                            HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "unable to write raw data to file");
                    } /* end if */
                    mpi_round=(++mpi_round)%mpi_size;

                    /* Indicate that blocks are being written */
                    blocks_written=1;
                } /* end if */
                else {
#endif /* H5_HAVE_PARALLEL */
                    if (H5F_block_write(f, H5FD_MEM_DRAW, udata.addr, udata.key.nbytes, dxpl_id, chunk)<0)
                        HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "unable to write raw data to file");
#ifdef H5_HAVE_PARALLEL
                } /* end else */
#endif /* H5_HAVE_PARALLEL */
            } /* end if */
        } /* end if */
	
        /* Increment indices */
        for (i=layout->ndims-1, carry=1; i>=0 && carry; --i) {
            chunk_offset[i] += layout->dim[i];
            if (chunk_offset[i] >= (hssize_t)(space_dim[i]))
                chunk_offset[i] = 0;
            else
                carry = 0;
        } /* end for */
    } /* end while */

#ifdef H5_HAVE_PARALLEL
    /* Only need to block at the barrier if we actually allocated a chunk */
    /* And if we are using an MPI-capable file driver */
    if(using_mpi && blocks_written) {
        /* Wait at barrier to avoid race conditions where some processes are
         * still writing out chunks and other processes race ahead to read
         * them in, getting bogus data.
         */
        if (MPI_SUCCESS != (mpi_code=MPI_Barrier(mpi_comm)))
            HMPI_GOTO_ERROR(FAIL, "MPI_Barrier failed", mpi_code);
    } /* end if */
#endif /* H5_HAVE_PARALLEL */

done:
    /* Free the chunk for fill values */
    if(chunk!=NULL)
        H5MM_xfree(chunk);

    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function: H5F_istore_prune_by_extent
 *
 * Purpose: This function searches for chunks that are no longer necessary both in the
 *  raw data cache and in the B-tree. 
 *
 * Return: Success: 0, Failure: -1
 *
 * Programmer: Pedro Vicente, pvn@ncsa.uiuc.edu
 * Algorithm: Robb Matzke
 *
 * Date: March 27, 2002
 *
 * The algorithm is:
 *
 *  For chunks that are no longer necessary:
 *
 *  1. Search in the raw data cache for each chunk 
 *  2. If found then preempt it from the cache
 *  3. Search in the B-tree for each chunk 
 *  4. If found then remove it from the B-tree and deallocate file storage for the chunk
 *
 * This example shows a 2d dataset of 90x90 with a chunk size of 20x20. 
 *
 *
 *     0         20        40        60        80    90   100
 *    0 +---------+---------+---------+---------+-----+...+
 *      |:::::X::::::::::::::         :         :     |   :
 *      |:::::::X::::::::::::         :         :     |   :   Key
 *      |::::::::::X:::::::::         :         :     |   :   --------
 *      |::::::::::::X:::::::         :         :     |   :  +-+ Dataset
 *    20+::::::::::::::::::::.........:.........:.....+...:  | | Extent
 *      |         :::::X:::::         :         :     |   :  +-+
 *      |         :::::::::::         :         :     |   :
 *      |         :::::::::::         :         :     |   :  ... Chunk
 *      |         :::::::X:::         :         :     |   :  : : Boundary
 *    40+.........:::::::::::.........:.........:.....+...:  :.:
 *      |         :         :         :         :     |   :
 *      |         :         :         :         :     |   :  ... Allocated
 *      |         :         :         :         :     |   :  ::: & Filled
 *      |         :         :         :         :     |   :  ::: Chunk
 *    60+.........:.........:.........:.........:.....+...:
 *      |         :         :::::::X:::         :     |   :   X  Element
 *      |         :         :::::::::::         :     |   :      Written
 *      |         :         :::::::::::         :     |   :
 *      |         :         :::::::::::         :     |   :
 *    80+.........:.........:::::::::::.........:.....+...:   O  Fill Val
 *      |         :         :         :::::::::::     |   :      Explicitly
 *      |         :         :         ::::::X::::     |   :      Written    
 *    90+---------+---------+---------+---------+-----+   :
 *      :         :         :         :::::::::::         :
 *   100:.........:.........:.........:::::::::::.........:
 *
 *
 * We have 25 total chunks for this dataset, 5 of which have space
 * allocated in the file because they were written to one or more
 * elements. These five chunks (and only these five) also have entries in
 * the storage B-tree for this dataset.
 *
 * Now lets say we want to shrink the dataset down to 70x70:
 *
 *
 *      0         20        40        60   70   80    90   100
 *    0 +---------+---------+---------+----+----+-----+...+
 *      |:::::X::::::::::::::         :    |    :     |   :
 *      |:::::::X::::::::::::         :    |    :     |   :    Key           
 *      |::::::::::X:::::::::         :    |    :     |   :    --------      
 *      |::::::::::::X:::::::         :    |    :     |   :   +-+ Dataset    
 *    20+::::::::::::::::::::.........:....+....:.....|...:   | | Extent     
 *      |         :::::X:::::         :    |    :     |   :   +-+            
 *      |         :::::::::::         :    |    :     |   :                  
 *      |         :::::::::::         :    |    :     |   :   ... Chunk      
 *      |         :::::::X:::         :    |    :     |   :   : : Boundary   
 *    40+.........:::::::::::.........:....+....:.....|...:   :.:            
 *      |         :         :         :    |    :     |   :                  
 *      |         :         :         :    |    :     |   :   ... Allocated  
 *      |         :         :         :    |    :     |   :   ::: & Filled   
 *      |         :         :         :    |    :     |   :   ::: Chunk      
 *    60+.........:.........:.........:....+....:.....|...:                  
 *      |         :         :::::::X:::    |    :     |   :    X  Element    
 *      |         :         :::::::::::    |    :     |   :       Written    
 *      +---------+---------+---------+----+    :     |   :                  
 *      |         :         :::::::::::         :     |   :                  
 *    80+.........:.........:::::::::X:.........:.....|...:    O  Fill Val   
 *      |         :         :         :::::::::::     |   :       Explicitly 
 *      |         :         :         ::::::X::::     |   :       Written    
 *    90+---------+---------+---------+---------+-----+   :
 *      :         :         :         :::::::::::         :
 *   100:.........:.........:.........:::::::::::.........:
 *
 *
 * That means that the nine chunks along the bottom and right side should
 * no longer exist. Of those nine chunks, (0,80), (20,80), (40,80),
 * (60,80), (80,80), (80,60), (80,40), (80,20), and (80,0), one is actually allocated 
 * that needs to be released.
 * To release the chunks, we traverse the B-tree to obtain a list of unused
 * allocated chunks, and then call H5B_remove() for each chunk.
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5F_istore_prune_by_extent(H5F_t *f, hid_t dxpl_id, const H5O_layout_t *layout, const H5S_t * space)
{
    H5F_rdcc_t             *rdcc = &(f->shared->rdcc);	/*raw data chunk cache */
    H5F_rdcc_ent_t         *ent = NULL, *next = NULL;	/*cache entry  */
    unsigned                u;	/*counters  */
    int                     found = 0;	/*remove this entry  */
    H5F_istore_ud1_t        udata;	/*B-tree pass-through */
    hsize_t                 curr_dims[H5O_LAYOUT_NDIMS];	/*current dataspace dimensions */
    herr_t      ret_value=SUCCEED;       /* Return value */

    FUNC_ENTER_NOAPI(H5F_istore_prune_by_extent, FAIL);

    /* Check args */
    assert(f);
    assert(layout && H5D_CHUNKED == layout->type);
    assert(layout->ndims > 0 && layout->ndims <= H5O_LAYOUT_NDIMS);
    assert(H5F_addr_defined(layout->addr));
    assert(space);

    /* Go get the rank & dimensions */
    if(H5S_get_simple_extent_dims(space, curr_dims, NULL) < 0)
	HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get dataset dimensions");

 /*-------------------------------------------------------------------------
  * Figure out what chunks are no longer in use for the specified extent 
  * and release them from the linked list raw data cache
  *-------------------------------------------------------------------------
  */
    for(ent = rdcc->head; ent; ent = next) {
	next = ent->next;

        /* Make certain we are dealing with the correct B-tree, etc */
        if (layout->ndims==ent->layout->ndims &&
                H5F_addr_eq(layout->addr, ent->layout->addr)) {
            found = 0;
            for(u = 0; u < ent->layout->ndims - 1; u++) {
                if((hsize_t)ent->offset[u] > curr_dims[u]) {
                    found = 1;
                    break;
                }
            }
        } /* end if */

	if(found) {
#if defined (H5F_ISTORE_DEBUG)
	    HDfputs("cache:remove:[", stdout);
	    for(u = 0; u < ent->layout->ndims - 1; u++) {
		HDfprintf(stdout, "%s%Hd", u ? ", " : "", ent->offset[u]);
	    }
	    HDfputs("]\n", stdout);
#endif

	    /* Preempt the entry from the cache, but do not flush it to disk */
	    if(H5F_istore_preempt(f, dxpl_id, ent, FALSE) < 0)
		HGOTO_ERROR(H5E_IO, H5E_CANTINIT, 0, "unable to preempt chunk");
	}
    }

/*-------------------------------------------------------------------------
 * Check if there are any chunks on the B-tree
 *-------------------------------------------------------------------------
 */

    HDmemset(&udata, 0, sizeof udata);
    udata.stream = stdout;
    udata.mesg.addr = layout->addr;
    udata.mesg.ndims = layout->ndims;
    for(u = 0; u < udata.mesg.ndims; u++)
	udata.mesg.dim[u] = layout->dim[u];
    udata.dims = curr_dims;

    if(H5B_iterate(f, dxpl_id, H5B_ISTORE, H5F_istore_prune_extent, layout->addr, &udata) < 0)
	HGOTO_ERROR(H5E_IO, H5E_CANTINIT, 0, "unable to iterate over B-tree");

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function: H5F_istore_prune_extent
 *
 * Purpose: Search for chunks that are no longer necessary in the B-tree. 
 *
 * Return: Success: 0, Failure: -1
 *
 * Programmer: Pedro Vicente, pvn@ncsa.uiuc.edu
 *
 * Date: March 26, 2002
 *
 * Comments: Called by H5B_prune_by_extent, part of H5B_ISTORE
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static H5B_iterate_t
H5F_istore_prune_extent(H5F_t *f, hid_t dxpl_id, void *_lt_key, haddr_t UNUSED addr,
        void UNUSED *_rt_key, void *_udata)
{
    H5F_istore_ud1_t       *bt_udata = (H5F_istore_ud1_t *)_udata;
    H5F_istore_key_t       *lt_key = (H5F_istore_key_t *)_lt_key;
    unsigned                u;
    H5F_istore_ud1_t        udata;
    H5B_iterate_t           ret_value=H5B_ITER_CONT;       /* Return value */

    /* The LT_KEY is the left key (the one that describes the chunk). It points to a chunk of 
     * storage that contains the beginning of the logical address space represented by UDATA.
     */

    FUNC_ENTER_NOINIT(H5F_istore_prune_extent);

    /* Figure out what chunks are no longer in use for the specified extent and release them */
    for(u = 0; u < bt_udata->mesg.ndims - 1; u++)
	if((hsize_t)lt_key->offset[u] > bt_udata->dims[u]) {
#if defined (H5F_ISTORE_DEBUG)
            HDfputs("b-tree:remove:[", bt_udata->stream);
            for(u = 0; u < bt_udata->mesg.ndims - 1; u++) {
                HDfprintf(bt_udata->stream, "%s%Hd", u ? ", " : "",
                        lt_key->offset[u]);
            }
            HDfputs("]\n", bt_udata->stream);
#endif

            HDmemset(&udata, 0, sizeof udata);
            udata.key = *lt_key;
            udata.mesg = bt_udata->mesg;

            /* Remove */
            if(H5B_remove(f, dxpl_id, H5B_ISTORE, bt_udata->mesg.addr, &udata) < 0)
                HGOTO_ERROR(H5E_SYM, H5E_CANTINIT, H5B_ITER_ERROR, "unable to remove entry");
	    break;
	} /* end if */

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function: H5F_istore_remove
 *
 * Purpose: Removes chunks that are no longer necessary in the B-tree. 
 *
 * Return: Success: 0, Failure: -1
 *
 * Programmer: Robb Matzke
 *             Pedro Vicente, pvn@ncsa.uiuc.edu
 *
 * Date: March 28, 2002
 *
 * Comments: Part of H5B_ISTORE
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
static H5B_ins_t
H5F_istore_remove(H5F_t *f, hid_t dxpl_id, haddr_t addr, void *_lt_key /*in,out */ ,
	hbool_t *lt_key_changed /*out */ ,
	void UNUSED * _udata /*in,out */ ,
	void UNUSED * _rt_key /*in,out */ ,
	hbool_t *rt_key_changed /*out */ )
{
    H5F_istore_key_t       *lt_key = (H5F_istore_key_t *)_lt_key;
    H5B_ins_t ret_value=H5B_INS_REMOVE;         /* Return value */

    FUNC_ENTER_NOAPI(H5F_istore_remove,H5B_INS_ERROR);

    H5FD_free(f->shared->lf, H5FD_MEM_DRAW, dxpl_id, addr, (hsize_t)lt_key->nbytes);
    *lt_key_changed = FALSE;
    *rt_key_changed = FALSE;

done:
    FUNC_LEAVE_NOAPI(ret_value);
}


/*-------------------------------------------------------------------------
 * Function: H5F_istore_initialize_by_extent
 *
 * Purpose:  This function searches for chunks that have to be initialized with the fill
 *   value both in the raw data cache and in the B-tree. 
 *
 * Return: Success: 0, Failure: -1
 *
 * Programmer: Pedro Vicente, pvn@ncsa.uiuc.edu
 *
 * Date: April 4, 2002
 *
 * Comments: 
 *
 * (See the example of H5F_istore_prune_by_extent)
 * Next, there are seven chunks where the database extent boundary is
 * within the chunk. We find those seven just like we did with the previous nine.
 * Fot the ones that are allocated we initialize the part that lies outside the boundary 
 * with the fill value.
 *
 * Modifications:
 *
 *-------------------------------------------------------------------------
 */
herr_t
H5F_istore_initialize_by_extent(H5F_t *f, hid_t dxpl_id, const H5O_layout_t *layout,
        H5P_genplist_t *dc_plist, const H5S_t * space)
{
    uint8_t                *chunk = NULL;	/*the file chunk  */
    unsigned                idx_hint = 0;	/*input value for H5F_istore_lock */
    hssize_t                chunk_offset[H5O_LAYOUT_NDIMS];	/*logical location of the chunks */
    hsize_t                 idx_cur[H5O_LAYOUT_NDIMS];	/*multi-dimensional counters */
    hsize_t                 idx_min[H5O_LAYOUT_NDIMS];
    hsize_t                 idx_max[H5O_LAYOUT_NDIMS];
    hsize_t                 sub_size[H5O_LAYOUT_NDIMS];
    hsize_t                 naccessed;	/*bytes accessed in chunk */
    hsize_t                 end_chunk;	/*chunk position counter */
    hssize_t                start[H5O_LAYOUT_NDIMS];	/*starting location of hyperslab */
    hsize_t                 count[H5O_LAYOUT_NDIMS];	/*element count of hyperslab */
    hsize_t                 size[H5O_LAYOUT_NDIMS];	/*current size of dimensions */
    H5S_t                  *space_chunk = NULL;	/*dataspace for a chunk */
    hsize_t                 curr_dims[H5O_LAYOUT_NDIMS];	/*current dataspace dimensions */
    int                     rank;	/*current # of dimensions */
    int                     i, carry;	/*counters  */
    unsigned                u;
    int                     found = 0;	/*initialize this entry  */
    H5O_pline_t             pline;      /* I/O pipeline information */
    H5O_fill_t              fill;       /* Fill value information */
    herr_t	            ret_value=SUCCEED;	/* Return value */

    FUNC_ENTER_NOAPI(H5F_istore_initialize_by_extent, FAIL);

    /* Check args */
    assert(f);
    assert(layout && H5D_CHUNKED == layout->type);
    assert(layout->ndims > 0 && layout->ndims <= H5O_LAYOUT_NDIMS);
    assert(H5F_addr_defined(layout->addr));
    assert(space);

    /* Get necessary properties from property list */
    if(H5P_get(dc_plist, H5D_CRT_FILL_VALUE_NAME, &fill) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get fill value");
    if(H5P_get(dc_plist, H5D_CRT_DATA_PIPELINE_NAME, &pline) < 0)
        HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get data pipeline");

    /* Reset start & count arrays */
    HDmemset(start, 0, sizeof(start));
    HDmemset(count, 0, sizeof(count));

    /* Go get the rank & dimensions */
    if((rank = H5S_get_simple_extent_dims(space, curr_dims, NULL)) < 0)
	HGOTO_ERROR(H5E_DATASET, H5E_CANTGET, FAIL, "can't get dataset dimensions");

    /* Copy current dimensions */
    for(i = 0; i < rank; i++)
	size[i] = curr_dims[i];
    size[i] = layout->dim[i];

    /* Create a data space for a chunk & set the extent */
    if(NULL == (space_chunk = H5S_create(H5S_SIMPLE)))
	HGOTO_ERROR(H5E_DATASPACE, H5E_CANTCREATE, FAIL, "can't create simple dataspace");
    if(H5S_set_extent_simple(space_chunk, (unsigned)rank, layout->dim, NULL) < 0)
	HGOTO_ERROR(H5E_DATASPACE, H5E_CANTINIT, FAIL, "can't set dimensions");

/*
 * Set up multi-dimensional counters (idx_min, idx_max, and idx_cur) and
 * loop through the chunks copying each chunk from the application to the
 * chunk cache.
 */
    for(u = 0; u < layout->ndims; u++) {
	idx_min[u] = 0;
	idx_max[u] = (size[u] - 1) / layout->dim[u] + 1;
	idx_cur[u] = idx_min[u];
    } /* end for */

    /* Loop over all chunks */
    carry=0;
    while(carry==0) {
	for(u = 0, naccessed = 1; u < layout->ndims; u++) {
	    /* The location and size of the chunk being accessed */
	    chunk_offset[u] = idx_cur[u] * (hssize_t)(layout->dim[u]);
	    sub_size[u] = MIN((idx_cur[u] + 1) * layout->dim[u],
		    size[u]) - chunk_offset[u];
	    naccessed *= sub_size[u];
	} /* end for */

	/* 
	 * Figure out what chunks have to be initialized. These are the chunks where the dataspace 
	 * extent boundary is within the chunk
	 */
	for(u = 0, found = 0; u < layout->ndims - 1; u++) {
	    end_chunk = chunk_offset[u] + layout->dim[u];
	    if(end_chunk > size[u]) {
		found = 1;
		break;
	    }
	} /* end for */

	if(found) {

	    if(NULL == (chunk = H5F_istore_lock(f, dxpl_id, layout, &pline, &fill,
			    chunk_offset, FALSE, &idx_hint)))
		HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "unable to read raw data chunk");

	    if(H5S_select_all(space_chunk,1) < 0)
		HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "unable to select space");

	    for(i = 0; i < rank; i++)
		count[i] = MIN((idx_cur[i] + 1) * layout->dim[i], size[i] - chunk_offset[i]);

#if defined (H5F_ISTORE_DEBUG)
	    HDfputs("cache:initialize:offset:[", stdout);
	    for(u = 0; u < layout->ndims - 1; u++)
		HDfprintf(stdout, "%s%Hd", u ? ", " : "", chunk_offset[u]);
	    HDfputs("]", stdout);
	    HDfputs(":count:[", stdout);
	    for(u = 0; u < layout->ndims - 1; u++)
		HDfprintf(stdout, "%s%Hd", u ? ", " : "", count[u]);
	    HDfputs("]\n", stdout);
#endif

	    if(H5S_select_hyperslab(space_chunk, H5S_SELECT_NOTB, start, NULL,
			count, NULL) < 0)
		HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "unable to select hyperslab");

	    /* Fill the selection in the memory buffer */
            /* Use the size of the elements in the chunk directly instead of */
            /* relying on the fill.size, which might be set to 0 if there is */
            /* no fill-value defined for the dataset -QAK */
            H5_CHECK_OVERFLOW(size[rank],hsize_t,size_t);
	    if(H5S_select_fill(fill.buf, (size_t)size[rank], space_chunk, chunk) < 0)
		HGOTO_ERROR(H5E_DATASET, H5E_CANTENCODE, FAIL, "filling selection failed");

	    if(H5F_istore_unlock(f, dxpl_id, layout, &pline, TRUE,
                    chunk_offset, &idx_hint, chunk, (size_t)naccessed) < 0)
		HGOTO_ERROR(H5E_IO, H5E_WRITEERROR, FAIL, "unable to unlock raw data chunk");
	} /*found */

	/* Increment indices */
	for(i = layout->ndims - 1, carry = 1; i >= 0 && carry; --i) {
	    if(++idx_cur[i] >= idx_max[i])
		idx_cur[i] = idx_min[i];
	    else
		carry = 0;
	} /* end for */
    } /* end while */

done:
    if(space_chunk)
	H5S_close(space_chunk);

    FUNC_LEAVE_NOAPI(ret_value);
}
generated by cgit v0.12 at 2024-11-06 00:42:35 (GMT)