/* zzekixlk.f -- translated by f2c (version 19980913).
   You must link the resulting object file with the libraries:
	-lf2c -lm   (in that order)
*/

#include "f2c.h"

/* $Procedure ZZEKIXLK ( EK, look up record pointer in EK index ) */
/* Subroutine */ int zzekixlk_(integer *handle, integer *coldsc, integer *key,
	 integer *recptr)
{
    integer base, tree;
    extern /* Subroutine */ int zzektrdp_(integer *, integer *, integer *, 
	    integer *);
    integer q, r__;
    extern /* Subroutine */ int chkin_(char *, ftnlen);
    integer itype;
    extern /* Subroutine */ int dasrdi_(integer *, integer *, integer *, 
	    integer *);
    integer addrss;
    extern /* Subroutine */ int setmsg_(char *, ftnlen), errint_(char *, 
	    integer *, ftnlen), sigerr_(char *, ftnlen), chkout_(char *, 
	    ftnlen);

/* $ Abstract */

/*     Look up a specified record pointer from an EK index. */

/* $ Disclaimer */

/*     THIS SOFTWARE AND ANY RELATED MATERIALS WERE CREATED BY THE */
/*     CALIFORNIA INSTITUTE OF TECHNOLOGY (CALTECH) UNDER A U.S. */
/*     GOVERNMENT CONTRACT WITH THE NATIONAL AERONAUTICS AND SPACE */
/*     ADMINISTRATION (NASA). THE SOFTWARE IS TECHNOLOGY AND SOFTWARE */
/*     PUBLICLY AVAILABLE UNDER U.S. EXPORT LAWS AND IS PROVIDED "AS-IS" */
/*     TO THE RECIPIENT WITHOUT WARRANTY OF ANY KIND, INCLUDING ANY */
/*     WARRANTIES OF PERFORMANCE OR MERCHANTABILITY OR FITNESS FOR A */
/*     PARTICULAR USE OR PURPOSE (AS SET FORTH IN UNITED STATES UCC */
/*     SECTIONS 2312-2313) OR FOR ANY PURPOSE WHATSOEVER, FOR THE */
/*     SOFTWARE AND RELATED MATERIALS, HOWEVER USED. */

/*     IN NO EVENT SHALL CALTECH, ITS JET PROPULSION LABORATORY, OR NASA */
/*     BE LIABLE FOR ANY DAMAGES AND/OR COSTS, INCLUDING, BUT NOT */
/*     LIMITED TO, INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY KIND, */
/*     INCLUDING ECONOMIC DAMAGE OR INJURY TO PROPERTY AND LOST PROFITS, */
/*     REGARDLESS OF WHETHER CALTECH, JPL, OR NASA BE ADVISED, HAVE */
/*     REASON TO KNOW, OR, IN FACT, SHALL KNOW OF THE POSSIBILITY. */

/*     RECIPIENT BEARS ALL RISK RELATING TO QUALITY AND PERFORMANCE OF */
/*     THE SOFTWARE AND ANY RELATED MATERIALS, AND AGREES TO INDEMNIFY */
/*     CALTECH AND NASA FOR ALL THIRD-PARTY CLAIMS RESULTING FROM THE */
/*     ACTIONS OF RECIPIENT IN THE USE OF THE SOFTWARE. */

/* $ Required_Reading */

/*     EK */

/* $ Keywords */

/*     EK */
/*     PRIVATE */

/* $ Declarations */
/* $ Disclaimer */

/*     THIS SOFTWARE AND ANY RELATED MATERIALS WERE CREATED BY THE */
/*     CALIFORNIA INSTITUTE OF TECHNOLOGY (CALTECH) UNDER A U.S. */
/*     GOVERNMENT CONTRACT WITH THE NATIONAL AERONAUTICS AND SPACE */
/*     ADMINISTRATION (NASA). THE SOFTWARE IS TECHNOLOGY AND SOFTWARE */
/*     PUBLICLY AVAILABLE UNDER U.S. EXPORT LAWS AND IS PROVIDED "AS-IS" */
/*     TO THE RECIPIENT WITHOUT WARRANTY OF ANY KIND, INCLUDING ANY */
/*     WARRANTIES OF PERFORMANCE OR MERCHANTABILITY OR FITNESS FOR A */
/*     PARTICULAR USE OR PURPOSE (AS SET FORTH IN UNITED STATES UCC */
/*     SECTIONS 2312-2313) OR FOR ANY PURPOSE WHATSOEVER, FOR THE */
/*     SOFTWARE AND RELATED MATERIALS, HOWEVER USED. */

/*     IN NO EVENT SHALL CALTECH, ITS JET PROPULSION LABORATORY, OR NASA */
/*     BE LIABLE FOR ANY DAMAGES AND/OR COSTS, INCLUDING, BUT NOT */
/*     LIMITED TO, INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY KIND, */
/*     INCLUDING ECONOMIC DAMAGE OR INJURY TO PROPERTY AND LOST PROFITS, */
/*     REGARDLESS OF WHETHER CALTECH, JPL, OR NASA BE ADVISED, HAVE */
/*     REASON TO KNOW, OR, IN FACT, SHALL KNOW OF THE POSSIBILITY. */

/*     RECIPIENT BEARS ALL RISK RELATING TO QUALITY AND PERFORMANCE OF */
/*     THE SOFTWARE AND ANY RELATED MATERIALS, AND AGREES TO INDEMNIFY */
/*     CALTECH AND NASA FOR ALL THIRD-PARTY CLAIMS RESULTING FROM THE */
/*     ACTIONS OF RECIPIENT IN THE USE OF THE SOFTWARE. */


/*     Include Section:  EK Column Descriptor Parameters */

/*        ekcoldsc.inc Version 6    23-AUG-1995 (NJB) */


/*     Note:  The column descriptor size parameter CDSCSZ  is */
/*     declared separately in the include section CDSIZE$INC.FOR. */

/*     Offset of column descriptors, relative to start of segment */
/*     integer address range.  This number, when added to the last */
/*     integer address preceding the segment, yields the DAS integer */
/*     base address of the first column descriptor.  Currently, this */
/*     offset is exactly the size of a segment descriptor.  The */
/*     parameter SDSCSZ, which defines the size of a segment descriptor, */
/*     is declared in the include file eksegdsc.inc. */


/*     Size of column descriptor */


/*     Indices of various pieces of column descriptors: */


/*     CLSIDX is the index of the column's class code.  (We use the */
/*     word `class' to distinguish this item from the column's data */
/*     type.) */


/*     TYPIDX is the index of the column's data type code (CHR, INT, DP, */
/*     or TIME).  The type is actually implied by the class, but it */
/*     will frequently be convenient to look up the type directly. */



/*     LENIDX is the index of the column's string length value, if the */
/*     column has character type.  A value of IFALSE in this element of */
/*     the descriptor indicates that the strings have variable length. */


/*     SIZIDX is the index of the column's element size value.  This */
/*     descriptor element is meaningful for columns with fixed-size */
/*     entries.  For variable-sized columns, this value is IFALSE. */


/*     NAMIDX is the index of the base address of the column's name. */


/*     IXTIDX is the data type of the column's index.  IXTIDX */
/*     contains a type value only if the column is indexed. For columns */
/*     that are not indexed, the location IXTIDX contains the boolean */
/*     value IFALSE. */


/*     IXPIDX is a pointer to the column's index.  IXTPDX contains a */
/*     meaningful value only if the column is indexed.  The */
/*     interpretation of the pointer depends on the data type of the */
/*     index. */


/*     NFLIDX is the index of a flag indicating whether nulls are */
/*     permitted in the column.  The value at location NFLIDX is */
/*     ITRUE if nulls are permitted and IFALSE otherwise. */


/*     ORDIDX is the index of the column's ordinal position in the */
/*     list of columns belonging to the column's parent segment. */


/*     METIDX is the index of the column's integer metadata pointer. */
/*     This pointer is a DAS integer address. */


/*     The last position in the column descriptor is reserved.  No */
/*     parameter is defined to point to this location. */


/*     End Include Section:  EK Column Descriptor Parameters */

/* $ Disclaimer */

/*     THIS SOFTWARE AND ANY RELATED MATERIALS WERE CREATED BY THE */
/*     CALIFORNIA INSTITUTE OF TECHNOLOGY (CALTECH) UNDER A U.S. */
/*     GOVERNMENT CONTRACT WITH THE NATIONAL AERONAUTICS AND SPACE */
/*     ADMINISTRATION (NASA). THE SOFTWARE IS TECHNOLOGY AND SOFTWARE */
/*     PUBLICLY AVAILABLE UNDER U.S. EXPORT LAWS AND IS PROVIDED "AS-IS" */
/*     TO THE RECIPIENT WITHOUT WARRANTY OF ANY KIND, INCLUDING ANY */
/*     WARRANTIES OF PERFORMANCE OR MERCHANTABILITY OR FITNESS FOR A */
/*     PARTICULAR USE OR PURPOSE (AS SET FORTH IN UNITED STATES UCC */
/*     SECTIONS 2312-2313) OR FOR ANY PURPOSE WHATSOEVER, FOR THE */
/*     SOFTWARE AND RELATED MATERIALS, HOWEVER USED. */

/*     IN NO EVENT SHALL CALTECH, ITS JET PROPULSION LABORATORY, OR NASA */
/*     BE LIABLE FOR ANY DAMAGES AND/OR COSTS, INCLUDING, BUT NOT */
/*     LIMITED TO, INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY KIND, */
/*     INCLUDING ECONOMIC DAMAGE OR INJURY TO PROPERTY AND LOST PROFITS, */
/*     REGARDLESS OF WHETHER CALTECH, JPL, OR NASA BE ADVISED, HAVE */
/*     REASON TO KNOW, OR, IN FACT, SHALL KNOW OF THE POSSIBILITY. */

/*     RECIPIENT BEARS ALL RISK RELATING TO QUALITY AND PERFORMANCE OF */
/*     THE SOFTWARE AND ANY RELATED MATERIALS, AND AGREES TO INDEMNIFY */
/*     CALTECH AND NASA FOR ALL THIRD-PARTY CLAIMS RESULTING FROM THE */
/*     ACTIONS OF RECIPIENT IN THE USE OF THE SOFTWARE. */


/*     Include Section:  EK Data Page Parameters */

/*        ekfilpar.inc  Version 1  03-APR-1995 (NJB) */

/*     These parameters apply to EK files using architecture 4. */
/*     These files use a paged DAS file as their underlying file */
/*     structure. */

/*     In paged DAS EK files, data pages are structured:  they contain */
/*     metadata as well as data.  The metadata is located in the last */
/*     few addresses of each page, so as to interfere as little as */
/*     possible with calculation of data addresses. */

/*     Each data page belongs to exactly one segment.  Some bookkeeping */
/*     information, such as record pointers, is also stored in data */
/*     pages. */

/*     Each page contains a forward pointer that allows rapid lookup */
/*     of data items that span multiple pages.  Each page also keeps */
/*     track of the current number of links from its parent segment */
/*     to the page.  Link counts enable pages to `know' when they */
/*     are no longer in use by a segment; unused pages are deallocated */
/*     and returned to the free list. */

/*     The parameters in this include file depend on the parameters */
/*     declared in the include file ekpage.inc.  If those parameters */
/*     change, this file must be updated.  The specified parameter */
/*     declarations we need from that file are: */

/*        INTEGER               PGSIZC */
/*        PARAMETER           ( PGSIZC = 1024 ) */

/*        INTEGER               PGSIZD */
/*        PARAMETER           ( PGSIZD = 128 ) */

/*        INTEGER               PGSIZI */
/*        PARAMETER           ( PGSIZI = 256 ) */



/*     Character pages use an encoding mechanism to represent integer */
/*     metadata.  Each integer is encoded in five consecutive */
/*     characters. */


/*     Character data page parameters: */


/*     Size of encoded integer: */


/*     Usable page size: */


/*     Location of character forward pointer: */


/*     Location of character link count: */


/*     Double precision data page parameters: */

/*     Usable page size: */


/*     Location of d.p. forward pointer: */


/*     Location of d.p. link count: */


/*     Integer data page parameters: */

/*     Usable page size: */


/*     Location of integer forward pointer: */


/*     Location of integer link count: */


/*     End Include Section:  EK Data Page Parameters */

/* $ Disclaimer */

/*     THIS SOFTWARE AND ANY RELATED MATERIALS WERE CREATED BY THE */
/*     CALIFORNIA INSTITUTE OF TECHNOLOGY (CALTECH) UNDER A U.S. */
/*     GOVERNMENT CONTRACT WITH THE NATIONAL AERONAUTICS AND SPACE */
/*     ADMINISTRATION (NASA). THE SOFTWARE IS TECHNOLOGY AND SOFTWARE */
/*     PUBLICLY AVAILABLE UNDER U.S. EXPORT LAWS AND IS PROVIDED "AS-IS" */
/*     TO THE RECIPIENT WITHOUT WARRANTY OF ANY KIND, INCLUDING ANY */
/*     WARRANTIES OF PERFORMANCE OR MERCHANTABILITY OR FITNESS FOR A */
/*     PARTICULAR USE OR PURPOSE (AS SET FORTH IN UNITED STATES UCC */
/*     SECTIONS 2312-2313) OR FOR ANY PURPOSE WHATSOEVER, FOR THE */
/*     SOFTWARE AND RELATED MATERIALS, HOWEVER USED. */

/*     IN NO EVENT SHALL CALTECH, ITS JET PROPULSION LABORATORY, OR NASA */
/*     BE LIABLE FOR ANY DAMAGES AND/OR COSTS, INCLUDING, BUT NOT */
/*     LIMITED TO, INCIDENTAL OR CONSEQUENTIAL DAMAGES OF ANY KIND, */
/*     INCLUDING ECONOMIC DAMAGE OR INJURY TO PROPERTY AND LOST PROFITS, */
/*     REGARDLESS OF WHETHER CALTECH, JPL, OR NASA BE ADVISED, HAVE */
/*     REASON TO KNOW, OR, IN FACT, SHALL KNOW OF THE POSSIBILITY. */

/*     RECIPIENT BEARS ALL RISK RELATING TO QUALITY AND PERFORMANCE OF */
/*     THE SOFTWARE AND ANY RELATED MATERIALS, AND AGREES TO INDEMNIFY */
/*     CALTECH AND NASA FOR ALL THIRD-PARTY CLAIMS RESULTING FROM THE */
/*     ACTIONS OF RECIPIENT IN THE USE OF THE SOFTWARE. */


/*     Include Section:  EK Das Paging Parameters */

/*        ekpage.inc  Version 4    25-AUG-1995 (NJB) */



/*     The EK DAS paging system makes use of the integer portion */
/*     of an EK file's DAS address space to store the few numbers */
/*     required to describe the system's state.  The allocation */
/*     of DAS integer addresses is shown below. */


/*                       DAS integer array */

/*        +--------------------------------------------+ */
/*        |            EK architecture code            |  Address = 1 */
/*        +--------------------------------------------+ */
/*        |      Character page size (in DAS words)    | */
/*        +--------------------------------------------+ */
/*        |        Character page base address         | */
/*        +--------------------------------------------+ */
/*        |      Number of character pages in file     | */
/*        +--------------------------------------------+ */
/*        |   Number of character pages on free list   | */
/*        +--------------------------------------------+ */
/*        |      Character free list head pointer      |  Address = 6 */
/*        +--------------------------------------------+ */
/*        |                                            |  Addresses = */
/*        |           Metadata for d.p. pages          |    7--11 */
/*        |                                            | */
/*        +--------------------------------------------+ */
/*        |                                            |  Addresses = */
/*        |         Metadata for integer pages         |    12--16 */
/*        |                                            | */
/*        +--------------------------------------------+ */
/*                              . */
/*                              . */
/*                              . */
/*        +--------------------------------------------+ */
/*        |                                            |  End Address = */
/*        |                Unused space                |  integer page */
/*        |                                            |  end */
/*        +--------------------------------------------+ */
/*        |                                            |  Start Address = */
/*        |             First integer page             |  integer page */
/*        |                                            |  base */
/*        +--------------------------------------------+ */
/*                              . */
/*                              . */
/*                              . */
/*        +--------------------------------------------+ */
/*        |                                            | */
/*        |              Last integer page             | */
/*        |                                            | */
/*        +--------------------------------------------+ */

/*     The following parameters indicate positions of elements in the */
/*     paging system metadata array: */



/*     Number of metadata items per data type: */


/*     Character metadata indices: */


/*     Double precision metadata indices: */


/*     Integer metadata indices: */


/*     Size of metadata area: */


/*     Page sizes, in units of DAS words of the appropriate type: */


/*     Default page base addresses: */


/*     End Include Section:  EK Das Paging Parameters */

/* $ Brief_I/O */

/*     Variable  I/O  Description */
/*     --------  ---  -------------------------------------------------- */
/*     HANDLE     I   File handle. */
/*     COLDSC     I   Column descriptor. */
/*     KEY        I   Key. */
/*     RECPTR     O   Record pointer. */

/* $ Detailed_Input */

/*     HANDLE         is an EK file handle.  The file may be open for */
/*                    reading or writing. */

/*     COLDSC         is the column descriptor of the column to which */
/*                    the index of interest belongs. */

/*     KEY            is the key of the record pointer of interest.  This */
/*                    key is the ordinal position of the record pointer */
/*                    in the index. */

/* $ Detailed_Output */

/*     RECPTR         is the record pointer corresponding to the input */
/*                    key.  This pointer gives the base address of */
/*                    the record pointer structure for the record having */
/*                    ordinal position KEY within the specified column, */
/*                    where the order is defined by the column's index. */

/* $ Parameters */

/*     None. */

/* $ Exceptions */

/*     1)  If HANDLE is invalid, the error will be diagnosed by routines */
/*         called by this routine. */

/*     2)  If KEY is out of range, the error will be diagnosed by */
/*         routines called by this routine. */

/*     3)  If an I/O error occurs while reading or the indicated */
/*         file, the error will be diagnosed by routines called by this */
/*         routine. */

/* $ Files */

/*     See the EK Required Reading for a discussion of the EK file */
/*     format. */

/* $ Particulars */

/*     This routine finds the record pointer for a record having a */
/*     specified ordinal position in a column, where the order is */
/*     defined by the column's index. */

/* $ Examples */

/*     See EKSRCH. */

/* $ Restrictions */

/*     None. */

/* $ Literature_References */

/*     None. */

/* $ Author_and_Institution */

/*     N.J. Bachman   (JPL) */

/* $ Version */

/* -    Beta Version 1.0.0, 09-NOV-1995 (NJB) */

/* -& */

/*     Local variables */


/*     Use discovery check-in. */

    itype = coldsc[5];
    if (itype == 1) {

/*        For type 1 indexes, the index pointer is the root node of */
/*        a B*-tree.  Just use the tree look up routine. */

	tree = coldsc[6];
	zzektrdp_(handle, &tree, key, recptr);
    } else if (itype == 2) {

/*        For type 2 indexes, the index pointer is the base address */
/*        of the index.  We must compute the offset from this base to */
/*        the index element having ordinal position KEY. */

	base = coldsc[6];
	q = (*key - 1) / 254;
	r__ = *key - q * 254;
	addrss = base + (q << 8) + r__;
	dasrdi_(handle, &addrss, &addrss, recptr);
    } else {

/*        Sorry, no other types of indexes are supported. */

	chkin_("ZZEKIXLK", (ftnlen)8);
	setmsg_("The index type # is not supported.", (ftnlen)34);
	errint_("#", &itype, (ftnlen)1);
	sigerr_("SPICE(INVALIDTYPE)", (ftnlen)18);
	chkout_("ZZEKIXLK", (ftnlen)8);
	return 0;
    }
    return 0;
} /* zzekixlk_ */

