/*
 * Copyright 2000, International Business Machines Corporation and others.
 * All Rights Reserved.
 * 
 * This software has been released under the terms of the IBM Public
 * License.  For details, see the LICENSE file in the top-level source
 * directory or online at http://www.openafs.org/dl/license10.html
 */

/*
 * afs_vnop_readdir.c - afs_readdir and bulk stat
 *
 * Implements:
 * BlobScan
 * afs_readdir_move
 * afs_bulkstat_send
 * afs_readdir/afs_readdir2(HP)
 * afs_readdir1 - HP and DUX NFS versions
 * 
 */

#include "../afs/param.h"	/* Should be always first */
#include "../afs/sysincludes.h"	/* Standard vendor system headers */
#include "../afs/afsincludes.h"	/* Afs-based standard headers */
#include "../afs/afs_stats.h" /* statistics */
#include "../afs/afs_cbqueue.h"
#include "../afs/nfsclient.h"
#include "../afs/afs_osidnlc.h"


/**
 * A few definitions. This is until we have a proper header file
 * which ahs prototypes for all functions
 */
    
extern struct DirEntry * afs_dir_GetBlob();
/*
 * AFS readdir vnodeop and bulk stat support.
 */

/* Saber C hates negative inode #s.  We're not going to talk about software
 * that could fail if it sees a negative inode #.
 */
#define FIXUPSTUPIDINODE(a)	((a) &= 0x7fffffff)

/* BlobScan is supposed to ensure that the blob reference refers to a valid
    directory entry.  It consults the allocation map in the page header
    to determine whether a blob is actually in use or not.

    More formally, BlobScan is supposed to return a new blob number which is just like
    the input parameter, only it is advanced over header or free blobs.
    
    Note that BlobScan switches pages if necessary.  BlobScan may return
    either 0 or an out-of-range blob number for end of file.

    BlobScan is used by the Linux port in a separate file, so it should not
    become static.
*/
#if defined(AFS_SGI62_ENV) || defined(AFS_SUN57_64BIT_ENV)
int BlobScan(ino64_t *afile, afs_int32 ablob)
#else
#ifdef AFS_LINUX_64BIT_KERNEL
int BlobScan(long *afile, afs_int32 ablob)
#else
int BlobScan(afs_int32 *afile, afs_int32 ablob)
#endif
#endif
{
    register afs_int32 relativeBlob;
    afs_int32 pageBlob;
    register struct PageHeader *tpe;
    register afs_int32 i;

    AFS_STATCNT(BlobScan);
    /* advance ablob over free and header blobs */
    while (1) {
	pageBlob = ablob & ~(EPP-1);	/* base blob in same page */
	tpe = (struct PageHeader *) afs_dir_GetBlob(afile, pageBlob);
	if (!tpe) return 0;		    /* we've past the end */
	relativeBlob = ablob - pageBlob;    /* relative to page's first blob */
	/* first watch for headers */
	if (pageBlob ==	0) {		    /* first dir page has extra-big header */
	    /* first page */
	    if (relativeBlob < DHE+1) relativeBlob = DHE+1;
	}
	else {				    /* others have one header blob */
	    if (relativeBlob == 0) relativeBlob = 1;
	}
	/* make sure blob is allocated */
	for(i = relativeBlob; i < EPP; i++) {
	    if (tpe->freebitmap[i>>3] & (1<<(i&7))) break;
	}
	/* now relativeBlob is the page-relative first allocated blob,
	 or EPP (if there are none in this page). */
	DRelease(tpe, 0);
	if (i != EPP) return i+pageBlob;
	ablob =	pageBlob + EPP;	/* go around again */
    }
    /* never get here */
}

#if !defined(AFS_LINUX20_ENV)
/* Changes to afs_readdir which affect dcache or vcache handling or use of
 * bulk stat data should also be reflected in the Linux specific verison of
 * the readdir routine.
 */

/*
 * The kernel don't like it so much to have large stuff on the stack.
 * Here we use a watered down version of the direct struct, since
 * its not too bright to double copy the strings anyway.
*/
#if !defined(UKERNEL)
#if defined(AFS_SGI_ENV)
/* Long form for 64 bit apps and kernel requests. */
struct min_dirent {     /* miniature dirent structure */
                        /* If struct dirent changes, this must too */
    ino_t       d_fileno; /* This is 32 bits for 3.5, 64 for 6.2+ */
    off64_t     d_off;
    u_short     d_reclen;
};
/* Short form for 32 bit apps. */
struct irix5_min_dirent {     /* miniature dirent structure */
                        /* If struct dirent changes, this must too */
    afs_uint32	d_fileno;
    afs_int32	d_off;
    u_short     d_reclen;
};
#ifdef AFS_SGI62_ENV
#define AFS_DIRENT32BASESIZE IRIX5_DIRENTBASESIZE
#define AFS_DIRENT64BASESIZE DIRENT64BASESIZE
#else
#define AFS_DIRENT32BASESIZE IRIX5_DIRENTBASESIZE
#define AFS_DIRENT64BASESIZE DIRENTBASESIZE
#endif /* AFS_SGI62_ENV */
#else
struct min_direct {	/* miniature direct structure */
			/* If struct direct changes, this must too */
#ifdef	AFS_SUN5_ENV
    afs_uint32	d_fileno;
    afs_int32	d_off;
    u_short	d_reclen;
#else
#if defined(AFS_SUN_ENV) || defined(AFS_AIX32_ENV)
    afs_int32	d_off;
#endif
#if     defined(AFS_HPUX100_ENV)
    unsigned long long d_off;
#endif
    afs_uint32	d_fileno;
    u_short	d_reclen;
    u_short	d_namlen;
#endif
};
#endif /* AFS_SGI_ENV */

#if	defined(AFS_HPUX_ENV) || defined(AFS_OSF_ENV)
struct minnfs_direct {
    afs_int32	d_off;		/* XXX */
    afs_uint32	d_fileno;
    u_short	d_reclen;
    u_short	d_namlen;
};
#define NDIRSIZ_LEN(len)   ((sizeof (struct dirent)+4 - (MAXNAMLEN+1)) + (((len)+1 + 3) &~ 3))
#endif
#endif /* !defined(UKERNEL) */


/*
 *------------------------------------------------------------------------------
 *
 * Keep a stack of about 256 fids for the bulk stat call.
 * Fill it during the readdir_move.  Later empty it...
 */

#define	READDIR_STASH	AFSCBMAX
struct AFSFid	afs_readdir_stash[READDIR_STASH];
int	afs_rd_stash_i = 0;

/*
 *------------------------------------------------------------------------------
 *
 * afs_readdir_move.
 *	mainly a kind of macro... makes getting the struct direct
 *	out to the user space easy... could take more parameters,
 *	but now just takes what it needs.
 *
 *
*/
#if	defined(AFS_HPUX100_ENV)
#define DIRSIZ_LEN(len) \
    ((sizeof (struct __dirent) - (_MAXNAMLEN+1)) + (((len)+1 + 3) &~ 3))
#else
#if	defined(AFS_SUN56_ENV)
#define DIRSIZ_LEN(len) ((18 + (len) + 1 + 7) & ~7 )
#else
#ifdef	AFS_SUN5_ENV
#define DIRSIZ_LEN(len)	((10 + (len) + 1 + (NBPW-1)) & ~(NBPW-1))
#else
#ifdef	AFS_DIRENT
#define DIRSIZ_LEN(len) \
    ((sizeof (struct dirent) - (MAXNAMLEN+1)) + (((len)+1 + 3) &~ 3))
#else
#if defined(AFS_SGI_ENV)
#ifndef AFS_SGI53_ENV
/* SGI 5.3 and later use 32/64 bit versions of directory size. */
#define DIRSIZ_LEN(len)		DIRENTSIZE(len)
#endif
#else /* AFS_SGI_ENV */
#define DIRSIZ_LEN(len) \
    ((sizeof (struct direct) - (MAXNAMLEN+1)) + (((len)+1 + 3) &~ 3))
#endif /* AFS_SGI_ENV */
#endif /* AFS_DIRENT */
#endif /* AFS_SUN5_ENV */
#endif /* AFS_SUN56_ENV */
#endif	/* AFS_HPUX100_ENV */

#ifdef AFS_AIX41_ENV
#define AFS_MOVE_LOCK()   AFS_GLOCK()
#define AFS_MOVE_UNLOCK() AFS_GUNLOCK()
#else
#define AFS_MOVE_LOCK()
#define AFS_MOVE_UNLOCK()
#endif

char bufofzeros[64];	/* gotta fill with something */
afs_readdir_move (de, vc, auio, slen, rlen, off) 
struct DirEntry *	de;
struct vcache *		vc;
struct	uio *		auio;
int			slen;
#ifdef AFS_SGI65_ENV
ssize_t			rlen;
#else
int			rlen;
#endif
int			off;
{
    int	code = 0;
#if	defined(AFS_SUN56_ENV)
    struct dirent64 *direntp;
#else
#ifdef	AFS_SUN5_ENV
    struct dirent *direntp;
#endif
#endif /* AFS_SUN56_ENV */
#ifndef	AFS_SGI53_ENV
    struct min_direct sdirEntry;
#endif /* AFS_SGI53_ENV */

    AFS_STATCNT(afs_readdir_move);
#ifdef	AFS_SGI53_ENV
{
    afs_int32 	use64BitDirent;

#ifdef AFS_SGI61_ENV
#ifdef AFS_SGI62_ENV
    use64BitDirent = ABI_IS(ABI_IRIX5_64,
			    GETDENTS_ABI(OSI_GET_CURRENT_ABI(), auio));
#else
    use64BitDirent = (auio->uio_segflg != UIO_USERSPACE) ? ABI_IRIX5_64 :
	(ABI_IS(ABI_IRIX5_64 | ABI_IRIX5_N32, u.u_procp->p_abi));
#endif
#else /* AFS_SGI61_ENV */
    use64BitDirent = (auio->uio_segflg != UIO_USERSPACE) ? ABI_IRIX5_64 :
	(ABI_IS(ABI_IRIX5_64, u.u_procp->p_abi));
#endif /* AFS_SGI61_ENV */

    if (use64BitDirent) {
	struct min_dirent sdirEntry;
	sdirEntry.d_fileno = (vc->fid.Fid.Volume << 16) + ntohl(de->fid.vnode);
	FIXUPSTUPIDINODE(sdirEntry.d_fileno);
	sdirEntry.d_reclen = rlen;
	sdirEntry.d_off = (off_t)off;
	AFS_UIOMOVE(&sdirEntry, AFS_DIRENT64BASESIZE, UIO_READ, auio, code);
	if (code == 0)
	    AFS_UIOMOVE(de->name, slen-1, UIO_READ, auio, code);
	if (code == 0)
	    AFS_UIOMOVE(bufofzeros,
			DIRENTSIZE(slen) - (AFS_DIRENT64BASESIZE + slen - 1),
			UIO_READ, auio, code);
	if (DIRENTSIZE(slen) < rlen) {
	    while(DIRENTSIZE(slen) < rlen) {
		int minLen = rlen - DIRENTSIZE(slen);
		if (minLen > sizeof(bufofzeros)) minLen = sizeof(bufofzeros);
		AFS_UIOMOVE(bufofzeros, minLen, UIO_READ, auio, code);
		rlen -= minLen;
	    }
	}
    } else {
	struct irix5_min_dirent sdirEntry;
	sdirEntry.d_fileno = (vc->fid.Fid.Volume << 16) + ntohl(de->fid.vnode);
	FIXUPSTUPIDINODE(sdirEntry.d_fileno);
	sdirEntry.d_reclen = rlen;
	sdirEntry.d_off = (afs_int32)off;
	AFS_UIOMOVE(&sdirEntry, AFS_DIRENT32BASESIZE, UIO_READ, auio, code);
	if (code == 0)
	    AFS_UIOMOVE(de->name, slen-1, UIO_READ, auio, code);
	if (code == 0)
	    AFS_UIOMOVE(bufofzeros,
			IRIX5_DIRENTSIZE(slen) -
			(AFS_DIRENT32BASESIZE + slen - 1),
			   UIO_READ, auio, code);
	if (IRIX5_DIRENTSIZE(slen) < rlen) {
	    while(IRIX5_DIRENTSIZE(slen) < rlen) {
		int minLen = rlen - IRIX5_DIRENTSIZE(slen);
		if (minLen > sizeof(bufofzeros)) minLen = sizeof(bufofzeros);
		AFS_UIOMOVE(bufofzeros, minLen, UIO_READ, auio, code);
		rlen -= minLen;
	    }
	}
    }
}
#else /* AFS_SGI53_ENV */
#ifdef	AFS_SUN5_ENV
#if	defined(AFS_SUN56_ENV)
    direntp = (struct dirent64 *) osi_AllocLargeSpace(AFS_LRALLOCSIZ);
#else
    direntp = (struct dirent *) osi_AllocLargeSpace(AFS_LRALLOCSIZ);
#endif
    direntp->d_ino =  (vc->fid.Fid.Volume << 16) + ntohl(de->fid.vnode);
    FIXUPSTUPIDINODE(direntp->d_ino);
    direntp->d_off = off;
    direntp->d_reclen = rlen;
    strcpy(direntp->d_name, de->name);
    AFS_UIOMOVE((caddr_t)direntp, rlen, UIO_READ, auio, code);
    osi_FreeLargeSpace((char *)direntp);
#else /* AFS_SUN5_ENV */
    /* Note the odd mechanism for building the inode number */
    sdirEntry.d_fileno = (vc->fid.Fid.Volume << 16) +
      ntohl(de->fid.vnode);
    FIXUPSTUPIDINODE(sdirEntry.d_fileno);
    sdirEntry.d_reclen = rlen;
#if !defined(AFS_SGI_ENV)
    sdirEntry.d_namlen = slen;
#endif
#if defined(AFS_SUN_ENV) || defined(AFS_AIX32_ENV) || defined(AFS_SGI_ENV)
    sdirEntry.d_off = off;
#endif

#if defined(AFS_SGI_ENV)
    AFS_UIOMOVE(&sdirEntry, DIRENTBASESIZE, UIO_READ, auio, code);
    if (code == 0)
	AFS_UIOMOVE(de->name, slen-1, UIO_READ, auio, code);
    if (code == 0)
        AFS_UIOMOVE(bufofzeros, DIRSIZ_LEN(slen) - (DIRENTBASESIZE + slen - 1), UIO_READ, auio, code);
#else /* AFS_SGI_ENV */
    AFS_MOVE_UNLOCK();
    AFS_UIOMOVE((char *)&sdirEntry, sizeof(sdirEntry), UIO_READ, auio, code);

    if (code == 0) {
	AFS_UIOMOVE(de->name, slen, UIO_READ, auio, code);
    }

    /* pad out the remaining characters with zeros */
    if (code == 0) { 
	AFS_UIOMOVE(bufofzeros, ((slen + 4) & ~3) - slen, UIO_READ,
		    auio, code);
    }
    AFS_MOVE_LOCK();
#endif /* AFS_SGI_ENV */

    /* pad out the difference between rlen and slen... */
    if (DIRSIZ_LEN(slen) < rlen)
	{
	AFS_MOVE_UNLOCK();
	while(DIRSIZ_LEN(slen) < rlen)
		{
		int minLen = rlen - DIRSIZ_LEN(slen);
		if (minLen > sizeof(bufofzeros))
			minLen = sizeof(bufofzeros);
		AFS_UIOMOVE(bufofzeros, minLen, UIO_READ, auio, code);
		rlen -= minLen;
		}
	AFS_MOVE_LOCK();
	}
#endif	/* AFS_SUN5_ENV */
#endif	/* AFS_SGI53_ENV */
    return(code);
}


/*
 *------------------------------------------------------------------------------
 *
 * Read directory entries.
 * There are some weird things to look out for here.  The uio_offset
 * field is either 0 or it is the offset returned from a previous
 * readdir.  It is an opaque value used by the server to find the
 * correct directory block to read.  The byte count must be at least
 * vtoblksz(vp) bytes.  The count field is the number of blocks to
 * read on the server.  This is advisory only, the server may return
 * only one block's worth of entries.  Entries may be compressed on
 * the server.
 *
 * This routine encodes knowledge of Vice dirs.
 */

void afs_bulkstat_send( avc, req )
    struct vcache * avc;
    struct vrequest * req;
{
    XSTATS_DECLS
    afs_rd_stash_i = 0;
}

/*
 * Here is the bad, bad, really bad news.
 * It has to do with 'offset' (seek locations).
*/

#if	defined(AFS_SUN5_ENV) || defined(AFS_SGI_ENV) || defined(AFS_OSF_ENV)
afs_readdir(OSI_VC_ARG(avc), auio, acred, eofp)
    int *eofp;
#else
#if defined(AFS_HPUX100_ENV) 
afs_readdir2(OSI_VC_ARG(avc), auio, acred)
#else
afs_readdir(OSI_VC_ARG(avc), auio, acred)
#endif 
#endif
    OSI_VC_DECL(avc);
    struct uio *auio;
    struct AFS_UCRED *acred; {
    struct vrequest treq;
    register struct dcache *tdc;
    afs_int32 origOffset, len, dirsiz;
    int code = 0;
    struct DirEntry *ode = 0, *nde = 0;
    int o_slen = 0, n_slen = 0;
    afs_uint32 us;
#if defined(AFS_SGI53_ENV)
    afs_int32 use64BitDirent;
#endif /* defined(AFS_SGI53_ENV) */
    OSI_VC_CONVERT(avc)
#ifdef	AFS_HPUX_ENV
    /*
     * XXX All the hacks for alloced sdirEntry and inlining of afs_readdir_move instead of calling
     * it is necessary for hpux due to stack problems that seem to occur when coming thru the nfs
     * translator side XXX
     */
    struct min_direct *sdirEntry = (struct min_direct *)osi_AllocSmallSpace(sizeof(struct min_direct));
    afs_int32 rlen;
#endif

    /* opaque value is pointer into a vice dir; use bit map to decide
	if the entries are in use.  Always assumed to be valid.  0 is
	special, means start of a new dir.  Int32 inode, followed by
	short reclen and short namelen.  Namelen does not include
	the null byte.  Followed by null-terminated string.
    */
    AFS_STATCNT(afs_readdir);

#if defined(AFS_SGI53_ENV)
#ifdef AFS_SGI61_ENV
#ifdef AFS_SGI62_ENV
    use64BitDirent = ABI_IS(ABI_IRIX5_64,
			    GETDENTS_ABI(OSI_GET_CURRENT_ABI(), auio));
#else
    use64BitDirent = (auio->uio_segflg != UIO_USERSPACE) ? ABI_IRIX5_64 :
	(ABI_IS(ABI_IRIX5_64 | ABI_IRIX5_N32, u.u_procp->p_abi));
#endif /* AFS_SGI62_ENV */
#else /* AFS_SGI61_ENV */
    use64BitDirent = (auio->uio_segflg != UIO_USERSPACE) ? ABI_IRIX5_64 :
	(ABI_IS(ABI_IRIX5_64, u.u_procp->p_abi));
#endif /* AFS_SGI61_ENV */
#endif /* defined(AFS_SGI53_ENV) */

#if	defined(AFS_SUN5_ENV) || defined(AFS_SGI_ENV) || defined(AFS_OSF_ENV)
    /* Not really used by the callee so we ignore it for now */
    if (eofp) *eofp = 0;
#endif
    if ( AfsLargeFileUio(auio)                  /* file is large than 2 GB */
        || AfsLargeFileSize(auio->uio_offset, auio->uio_resid) )
	return EFBIG;

    if (code = afs_InitReq(&treq, acred)) {
#ifdef	AFS_HPUX_ENV
	osi_FreeSmallSpace((char *)sdirEntry);
#endif
	return code;
    }
    /* update the cache entry */
tagain:
    code = afs_VerifyVCache(avc, &treq);
    if (code) goto done;
    /* get a reference to the entire directory */
    tdc = afs_GetDCache(avc, 0, &treq, &origOffset, &len, 1);
    if (!tdc) {
	code = ENOENT;
	goto done;
    }
    ObtainReadLock(&avc->lock);

    /*
     * Make sure that the data in the cache is current. There are two
     * cases we need to worry about:
     * 1. The cache data is being fetched by another process.
     * 2. The cache data is no longer valid
     */
    while ((avc->states & CStatd)
	   && (tdc->flags & DFFetching)
	   && hsame(avc->m.DataVersion, tdc->f.versionNo)) {
	tdc->flags |= DFWaiting;
	ReleaseReadLock(&avc->lock);
	afs_osi_Sleep(&tdc->validPos);
	ObtainReadLock(&avc->lock);
    }
    if (!(avc->states & CStatd)
	|| !hsame(avc->m.DataVersion, tdc->f.versionNo)) {
	ReleaseReadLock(&avc->lock);
	afs_PutDCache(tdc);
	goto tagain;
    }

    /*
     *	iterator for the directory reads.  Takes the AFS DirEntry
     *	structure and slams them into UFS direct structures.
     *	uses afs_readdir_move to get the struct to the user space.
     *
     *	The routine works by looking ahead one AFS directory entry.
     *	That's because the AFS entry we are currenly working with
     *	may not fit into the buffer the user has provided.  If it
     *	doesn't we have to change the size of the LAST AFS directory
     *	entry, so that it will FIT perfectly into the block the
     *	user has provided.
     *	
     *	The 'forward looking' of the code makes it a bit tough to read.
     *	Remember we need to get an entry, see if it it fits, then
     *	set it up as the LAST entry, and find the next one.
     *
     *	Tough to take: We give out an EINVAL if we don't have enough
     *	space in the buffer, and at the same time, don't have an entry
     *	to put into the buffer. This CAN happen if the first AFS entry
     *	we get can't fit into the 512 character buffer provided.  Seems
     *	it ought not happen... 
     *
     *	Assumption: don't need to use anything but one dc entry:
     *	this means the directory ought not be greater than 64k.
     */
    len = 0;
#ifdef AFS_HPUX_ENV
    auio->uio_fpflags = 0;
#endif
    while (code==0) {
	origOffset = auio->afsio_offset;
	/* scan for the next interesting entry scan for in-use blob otherwise up point at
	 * this blob note that ode, if non-zero, also represents a held dir page */
	if (!(us = BlobScan(&tdc->f.inode, (origOffset >> 5)) )
	    || !(nde = (struct DirEntry *) afs_dir_GetBlob(&tdc->f.inode, us) ) ) {
	    /* failed to setup nde, return what we've got, and release ode */
	    if (len) {
		/* something to hand over. */
#ifdef	AFS_HPUX_ENV
		sdirEntry->d_fileno = (avc->fid.Fid.Volume << 16) + ntohl(ode->fid.vnode);
		FIXUPSTUPIDINODE(sdirEntry->d_fileno);
		sdirEntry->d_reclen = rlen = auio->afsio_resid;
		sdirEntry->d_namlen = o_slen;
#if defined(AFS_SUN_ENV) || defined(AFS_AIX32_ENV) || defined(AFS_HPUX100_ENV)
		sdirEntry->d_off = origOffset;
#endif
		AFS_UIOMOVE((char *)sdirEntry, sizeof(*sdirEntry), UIO_READ, auio, code);
		if (code == 0)
		    AFS_UIOMOVE(ode->name, o_slen, UIO_READ, auio, code);
		/* pad out the remaining characters with zeros */
		if (code == 0) {
		    AFS_UIOMOVE(bufofzeros, ((o_slen + 4) & ~3) - o_slen, UIO_READ, auio, code);
		}
		/* pad out the difference between rlen and slen... */
		if (DIRSIZ_LEN(o_slen) < rlen) {
		    while(DIRSIZ_LEN(o_slen) < rlen) {
			int minLen = rlen - DIRSIZ_LEN(o_slen);
			if (minLen > sizeof(bufofzeros))
			    minLen = sizeof(bufofzeros);
			AFS_UIOMOVE(bufofzeros, minLen, UIO_READ, auio, code);
			rlen -= minLen;
		    }
		}
#else
		code = afs_readdir_move(ode, avc, auio, o_slen,
#if defined(AFS_SUN5_ENV)
		                        len, origOffset);
#else
					auio->afsio_resid, origOffset);
#endif
#endif /* AFS_HPUX_ENV */
#if !defined(AFS_SUN5_ENV)
		auio->afsio_resid = 0;
#endif
	    } else {
		/* nothin to hand over */
	    }
#if	defined(AFS_SUN5_ENV) || defined(AFS_SGI_ENV) || defined(AFS_OSF_ENV)
	if (eofp) *eofp = 1;	/* Set it properly */
#endif
	    if (ode) DRelease(ode, 0);
	    goto dirend;
	}
	/* by here nde is set */

	/* Do we have enough user space to carry out our mission? */
#if defined(AFS_SGI_ENV)
	n_slen = strlen(nde->name) + 1;	/* NULL terminate */
#else
	n_slen = strlen(nde->name);
#endif
#ifdef	AFS_SGI53_ENV
        dirsiz = use64BitDirent ? DIRENTSIZE(n_slen) :
	    IRIX5_DIRENTSIZE(n_slen);
	if (dirsiz >= (auio->afsio_resid-len)) {
#else
	if (DIRSIZ_LEN(n_slen) >= (auio->afsio_resid-len)) {
#endif /* AFS_SGI53_ENV */
	    /* No can do no more now; ya know... at this time */
	    DRelease (nde, 0); /* can't use this one. */
	    if (len) {
#ifdef	AFS_HPUX_ENV
		sdirEntry->d_fileno = (avc->fid.Fid.Volume << 16) + ntohl(ode->fid.vnode);
		FIXUPSTUPIDINODE(sdirEntry->d_fileno);
		sdirEntry->d_reclen = rlen = auio->afsio_resid;
		sdirEntry->d_namlen = o_slen;
#if defined(AFS_SUN_ENV) || defined(AFS_AIX32_ENV) || defined(AFS_HPUX100_ENV)
		sdirEntry->d_off = origOffset;
#endif
		AFS_UIOMOVE((char *)sdirEntry, sizeof(*sdirEntry), UIO_READ, auio, code);
		if (code == 0)
		    AFS_UIOMOVE(ode->name, o_slen, UIO_READ, auio, code);
		/* pad out the remaining characters with zeros */
		if (code == 0) {
		    AFS_UIOMOVE(bufofzeros, ((o_slen + 4) & ~3) - o_slen, UIO_READ, auio, code);
		}
		/* pad out the difference between rlen and slen... */
		if (DIRSIZ_LEN(o_slen) < rlen) {
		    while(DIRSIZ_LEN(o_slen) < rlen) {
			int minLen = rlen - DIRSIZ_LEN(o_slen);
			if (minLen > sizeof(bufofzeros))
			    minLen = sizeof(bufofzeros);
			AFS_UIOMOVE(bufofzeros, minLen, UIO_READ, auio, code);
			rlen -= minLen;
		    }
		}
#else /* AFS_HPUX_ENV */
		code = afs_readdir_move(ode, avc, auio, o_slen,
					auio->afsio_resid, origOffset);
#endif /* AFS_HPUX_ENV */
		/* this next line used to be AFSVFS40 or AIX 3.1, but is
		 * really generic */
		auio->afsio_offset = origOffset;
		auio->afsio_resid = 0;  
	    } else { /* trouble, can't give anything to the user! */
		/* even though he has given us a buffer, 
		 * even though we have something to give us,
		 * Looks like we lost something somewhere.
		 */
		code = EINVAL;
	    }
	    if (ode) DRelease(ode, 0);
	    goto dirend;
	}

	/*
	 * In any event, we move out the LAST de entry, getting ready
	 * to set up for the next one.
	 */
	if (len) {
#ifdef	AFS_HPUX_ENV
	    sdirEntry->d_fileno =
		(avc->fid.Fid.Volume << 16) + ntohl(ode->fid.vnode);
	    FIXUPSTUPIDINODE(sdirEntry->d_fileno);
	    sdirEntry->d_reclen = rlen = len;
	    sdirEntry->d_namlen = o_slen;
#if defined(AFS_SUN_ENV) || defined(AFS_AIX32_ENV) || defined(AFS_HPUX100_ENV)
	    sdirEntry->d_off = origOffset;
#endif
	    AFS_UIOMOVE((char *)sdirEntry, sizeof(*sdirEntry), UIO_READ,
			auio, code);
	    if (code == 0)
		AFS_UIOMOVE(ode->name, o_slen, UIO_READ, auio, code);
	    /* pad out the remaining characters with zeros */
	    if (code == 0) {
		AFS_UIOMOVE(bufofzeros, ((o_slen + 4) & ~3) - o_slen,
			    UIO_READ, auio, code);
	    }
	    /* pad out the difference between rlen and slen... */
	    if (DIRSIZ_LEN(o_slen) < rlen) {
		while(DIRSIZ_LEN(o_slen) < rlen) {
		    int minLen = rlen - DIRSIZ_LEN(o_slen);
		    if (minLen > sizeof(bufofzeros))
			minLen = sizeof(bufofzeros);
		    AFS_UIOMOVE(bufofzeros, minLen, UIO_READ, auio, code);
		    rlen -= minLen;
		}
	    }
#else /* AFS_HPUX_ENV */
	    code = afs_readdir_move (ode, avc, auio, o_slen, len, origOffset);
#endif /* AFS_HPUX_ENV */
	}
#ifdef	AFS_SGI53_ENV
        len = use64BitDirent ? DIRENTSIZE(o_slen = n_slen) :
	    IRIX5_DIRENTSIZE(o_slen = n_slen);
#else
	len = DIRSIZ_LEN( o_slen = n_slen );
#endif /* AFS_SGI53_ENV */
   	if (ode) DRelease(ode, 0);
	ode = nde;
	auio->afsio_offset = (afs_int32)((us + afs_dir_NameBlobs(nde->name)) << 5);
    }
    if (ode) DRelease(ode, 0);

dirend:
    afs_PutDCache(tdc);
    ReleaseReadLock(&avc->lock);

done:
#ifdef	AFS_HPUX_ENV
    osi_FreeSmallSpace((char *)sdirEntry);
#endif
    code = afs_CheckCode(code, &treq, 28);
    return code;
}

#if	defined(AFS_HPUX_ENV) || defined(AFS_OSF_ENV)
#ifdef	AFS_OSF_ENV
afs1_readdir(avc, auio, acred, eofp)
    int *eofp;
#else
afs1_readdir(avc, auio, acred)
#endif
    register struct vcache *avc;
    struct uio *auio;
    struct AFS_UCRED *acred; {
    struct vrequest treq;
    register struct dcache *tdc;
    afs_int32 origOffset, len;
    int code = 0;
    struct DirEntry *ode = 0, *nde = 0;
    int o_slen = 0, n_slen = 0;
    afs_uint32 us;
#if	defined(AFS_HPUX_ENV) || defined(AFS_OSF_ENV)
    /*
     * XXX All the hacks for alloced sdirEntry and inlining of afs_readdir_move instead of calling
     * it is necessary for hpux due to stack problems that seem to occur when coming thru the nfs
     * translator side XXX
     */
    struct minnfs_direct *sdirEntry = (struct minnfs_direct *)osi_AllocSmallSpace(sizeof(struct min_direct));
    afs_int32 rlen;
#endif

    AFS_STATCNT(afs_readdir);
#if	defined(AFS_SUN5_ENV) || defined(AFS_SGI_ENV) || defined(AFS_OSF_ENV)
    if (eofp) *eofp = 0;
#endif
    if (code = afs_InitReq(&treq, acred)) {
#ifdef	AFS_HPUX_ENV
	osi_FreeSmallSpace((char *)sdirEntry);
#endif
	return code;
    }
    /* update the cache entry */
tagain:
    code = afs_VerifyVCache(avc, &treq);
    if (code) goto done;
    /* get a reference to the entire directory */
    tdc = afs_GetDCache(avc, 0, &treq, &origOffset, &len, 1);
    if (!tdc) {
	code = ENOENT;
	goto done;
    }
    ObtainReadLock(&avc->lock);

    /*
     * Make sure that the data in the cache is current. There are two
     * cases we need to worry about:
     * 1. The cache data is being fetched by another process.
     * 2. The cache data is no longer valid
     */
    while ((avc->states & CStatd)
	   && (tdc->flags & DFFetching)
	   && hsame(avc->m.DataVersion, tdc->f.versionNo)) {
	tdc->flags |= DFWaiting;
	ReleaseReadLock(&avc->lock);
	afs_osi_Sleep(&tdc->validPos);
	ObtainReadLock(&avc->lock);
    }
    if (!(avc->states & CStatd)
	|| !hsame(avc->m.DataVersion, tdc->f.versionNo)) {
	ReleaseReadLock(&avc->lock);
	afs_PutDCache(tdc);
	goto tagain;
    }

    len = 0;
#ifdef AFS_HPUX_ENV
    auio->uio_fpflags = 0;
#endif
    while (code==0) {
	origOffset = auio->afsio_offset;

	/* scan for the next interesting entry scan for in-use blob otherwise up point at
	 * this blob note that ode, if non-zero, also represents a held dir page */
	if (!(us = BlobScan(&tdc->f.inode, (origOffset >> 5)) )
	    || !(nde = (struct DirEntry *) afs_dir_GetBlob(&tdc->f.inode, us) ) ) {
	    /* failed to setup nde, return what we've got, and release ode */
	    if (len) {
		/* something to hand over. */
#if	defined(AFS_HPUX_ENV) || defined(AFS_OSF_ENV)
		sdirEntry->d_fileno = (avc->fid.Fid.Volume << 16) + ntohl(ode->fid.vnode);
		FIXUPSTUPIDINODE(sdirEntry->d_fileno);
		sdirEntry->d_reclen = rlen = auio->afsio_resid;
		sdirEntry->d_namlen = o_slen;
		sdirEntry->d_off = origOffset;
		AFS_UIOMOVE((char *)sdirEntry, sizeof(*sdirEntry), UIO_READ, auio, code);
		if (code == 0) {
		    AFS_UIOMOVE(ode->name, o_slen, UIO_READ, auio, code);
		}
		/* pad out the remaining characters with zeros */
		if (code == 0) {
		    AFS_UIOMOVE(bufofzeros, ((o_slen + 4) & ~3) - o_slen, UIO_READ, auio, code);
		}
		/* pad out the difference between rlen and slen... */
		if (NDIRSIZ_LEN(o_slen) < rlen) {
		    while(NDIRSIZ_LEN(o_slen) < rlen) {
		        int minLen = rlen - NDIRSIZ_LEN(o_slen);
			if (minLen > sizeof(bufofzeros))
			    minLen = sizeof(bufofzeros);
			AFS_UIOMOVE(bufofzeros, minLen, UIO_READ, auio, code);
			rlen -= minLen;
		    }
		}
#else
		code = afs_readdir_move(ode, avc, auio, o_slen,
					auio->afsio_resid, origOffset);
#endif /* AFS_HPUX_ENV */
		auio->afsio_resid = 0;  
	    } else {
		/* nothin to hand over */
	    }
#if defined(AFS_SUN5_ENV) || defined(AFS_SGI_ENV) || defined(AFS_OSF_ENV)
	if (eofp) *eofp = 1;
#endif
	if (ode) DRelease(ode, 0);
	    goto dirend;
	}
	/* by here nde is set */

	/* Do we have enough user space to carry out our mission? */
#if defined(AFS_SGI_ENV)
	n_slen = strlen(nde->name) + 1;	/* NULL terminate */
#else
	n_slen = strlen(nde->name);
#endif
	if (NDIRSIZ_LEN(n_slen) >= (auio->afsio_resid-len)) {
	    /* No can do no more now; ya know... at this time */
	    DRelease (nde, 0); /* can't use this one. */
	    if (len) {
#if	defined(AFS_HPUX_ENV) || defined(AFS_OSF_ENV)
		sdirEntry->d_fileno = (avc->fid.Fid.Volume << 16) + ntohl(ode->fid.vnode);
		FIXUPSTUPIDINODE(sdirEntry->d_fileno);
		sdirEntry->d_reclen = rlen = auio->afsio_resid;
		sdirEntry->d_namlen = o_slen;
		sdirEntry->d_off = origOffset;
		AFS_UIOMOVE((char *)sdirEntry, sizeof(*sdirEntry), UIO_READ, auio, code);
		if (code == 0)
		    AFS_UIOMOVE(ode->name, o_slen, UIO_READ, auio, code);
		/* pad out the remaining characters with zeros */
		if (code == 0) {
		    AFS_UIOMOVE(bufofzeros, ((o_slen + 4) & ~3) - o_slen, UIO_READ, auio, code);
		}
		/* pad out the difference between rlen and slen... */
		if (NDIRSIZ_LEN(o_slen) < rlen) {
		    while(NDIRSIZ_LEN(o_slen) < rlen) {
			int minLen = rlen - NDIRSIZ_LEN(o_slen);
			if (minLen > sizeof(bufofzeros))
			    minLen = sizeof(bufofzeros);
			AFS_UIOMOVE(bufofzeros, minLen, UIO_READ, auio, code);
			rlen -= minLen;
		    }
		}
#else
		code = afs_readdir_move(ode, avc, auio, o_slen,
				auio->afsio_resid, origOffset);
#endif /* AFS_HPUX_ENV */
		/* this next line used to be AFSVFS40 or AIX 3.1, but is really generic */
		auio->afsio_offset = origOffset;
		auio->afsio_resid = 0;  
	    } else { /* trouble, can't give anything to the user! */
		/* even though he has given us a buffer, 
		 * even though we have something to give us,
		 * Looks like we lost something somewhere.
		 */
		code = EINVAL;
	    }
	    if (ode) DRelease(ode, 0);
	    goto dirend;
	}

	/*
	 * In any event, we move out the LAST de entry, getting ready
	 * to set up for the next one.
	 */
	if (len) {
#if	defined(AFS_HPUX_ENV) || defined(AFS_OSF_ENV)
	    sdirEntry->d_fileno = (avc->fid.Fid.Volume << 16) + ntohl(ode->fid.vnode);
	    FIXUPSTUPIDINODE(sdirEntry->d_fileno);
	    sdirEntry->d_reclen = rlen = len;
	    sdirEntry->d_namlen = o_slen;
	    sdirEntry->d_off = origOffset;
	    AFS_UIOMOVE((char *)sdirEntry, sizeof(*sdirEntry), UIO_READ, auio, code);
	    if (code == 0)
		AFS_UIOMOVE(ode->name, o_slen, UIO_READ, auio, code);
	    /* pad out the remaining characters with zeros */
	    if (code == 0) {
		AFS_UIOMOVE(bufofzeros, ((o_slen + 4) & ~3) - o_slen, UIO_READ, auio, code);
	    }
	    /* pad out the difference between rlen and slen... */
	    if (NDIRSIZ_LEN(o_slen) < rlen) {
		while(NDIRSIZ_LEN(o_slen) < rlen) {
		    int minLen = rlen - NDIRSIZ_LEN(o_slen);
		    if (minLen > sizeof(bufofzeros))
			minLen = sizeof(bufofzeros);
		    AFS_UIOMOVE(bufofzeros, minLen, UIO_READ, auio, code);
		    rlen -= minLen;
		}
	    }
#else
	    code = afs_readdir_move (ode, avc, auio, o_slen, len, origOffset);
#endif /* AFS_HPUX_ENV */
	}
	len = NDIRSIZ_LEN( o_slen = n_slen );
    	if (ode) DRelease(ode, 0);
	ode = nde;
	auio->afsio_offset = ((us + afs_dir_NameBlobs(nde->name)) << 5);
    }
    if (ode) DRelease(ode, 0);

dirend:
    afs_PutDCache(tdc);
    ReleaseReadLock(&avc->lock);

done:
#if	defined(AFS_HPUX_ENV) || defined(AFS_OSF_ENV)
    osi_FreeSmallSpace((char *)sdirEntry);
#endif
    code = afs_CheckCode(code, &treq, 29);
    return code;
}

#endif
#endif /* !AFS_LINUX20_ENV */
