home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
Cream of the Crop 1
/
Cream of the Crop 1.iso
/
PROGRAM
/
CBASE102.ARJ
/
CBKEYFIR.C
< prev
next >
Wrap
Text File
|
1991-09-23
|
3KB
|
144 lines
/* Copyright (c) 1989 Citadel */
/* All Rights Reserved */
/* #ident "@(#)cbkeyfir.c 1.5 - 91/09/23" */
#include <ansi.h>
/* ansi headers */
#include <errno.h>
#ifdef AC_STDLIB
#include <stdlib.h>
#endif
#ifdef AC_STRING
#include <string.h>
#endif
/* library headers */
#include <blkio.h>
#include <btree.h>
#include <lseq.h>
/* local headers */
#include "cbase_.h"
/*man---------------------------------------------------------------------------
NAME
cbkeyfirst - first cbase key
SYNOPSIS
#include <cbase.h>
int cbkeyfirst(cbp, field)
cbase_t *cbp;
int field;
DESCRIPTION
The cbkeyfirst function positions the key cursor of the specified
field in cbase cbp to the first key. The record cursor of cbp is
positioned to the record associated with that key. Other key
cursors are not affected.
cbkeyfirst will fail if one or more of the following is true:
[EINVAL] cbp is not a valid cbase pointer.
[EINVAL] field is not a valid field number for
cbase cbp.
[CBELOCK] cbp is not locked.
[CBENKEY] field is not a key.
[CBENOPEN] cbp is not open.
[CBENREC] cbp is empty.
SEE ALSO
cbkeylast, cbkeynext, cbkeyprev, cbreccnt, cbrecfirst.
DIAGNOSTICS
Upon successful completion, a value of 0 is returned. Otherwise,
a value of -1 is returned, and errno set to indicate the error.
------------------------------------------------------------------------------*/
#ifdef AC_PROTO
int cbkeyfirst(cbase_t *cbp, int field)
#else
int cbkeyfirst(cbp, field)
cbase_t *cbp;
int field;
#endif
{
void * buf = NULL;
cbrpos_t cbrpos = NIL;
lspos_t lspos = NIL;
/* validate arguments */
if (!cb_valid(cbp)) {
errno = EINVAL;
return -1;
}
/* check if not open */
if (!(cbp->flags & CBOPEN)) {
errno = CBENOPEN;
return -1;
}
/* validate arguments */
if (field < 0 || field >= cbp->fldc) {
errno = EINVAL;
return -1;
}
/* check if field not a key */
if (!(cbp->fldv[field].flags & CB_FKEY)) {
errno = CBENKEY;
return -1;
}
/* check if not locked */
if (!(cbp->flags & CBLOCKS)) {
errno = CBELOCK;
return -1;
}
/* check if cbase empty */
if (lsreccnt(cbp->lsp) == 0) {
errno = CBENREC;
return -1;
}
/* set key cursor to first key */
if (btfirst(cbp->btpv[field]) == -1) {
CBEPRINT;
return -1;
}
/* get record position */
if (btkeysize(cbp->btpv[field]) != (cbp->fldv[field].len + sizeof(cbrpos_t))) {
CBEPRINT;
errno = CBEPANIC;
return -1;
}
buf = calloc((size_t)1, btkeysize(cbp->btpv[field]));
if (buf == NULL) {
CBEPRINT;
errno = ENOMEM;
return -1;
}
if (btgetk(cbp->btpv[field], buf) == -1) {
CBEPRINT;
free(buf);
return -1;
}
memcpy(&cbrpos, (char *)buf + cbp->fldv[field].len, sizeof(cbrpos));
free(buf);
buf = NULL;
/* set record cursor */
lspos = cbrpos;
if (lssetcur(cbp->lsp, &lspos) == -1) {
CBEPRINT;
return -1;
}
return 0;
}