/****************************************************************************
* fs/nfs/nfs_util.h
*
* Copyright (C) 2012 Gregory Nutt. All rights reserved.
* Author: Gregory Nutt <spudmonkey@racsa.co.cr>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name NuttX nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/****************************************************************************
* Included Files
****************************************************************************/
#include <nuttx/config.h>
#include <sys/types.h>
#include <sys/time.h>
#include <stdint.h>
#include <queue.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
#include <assert.h>
#include <errno.h>
#include <assert.h>
#include <debug.h>
#include <nuttx/fs/dirent.h>
#include "rpc.h"
#include "nfs.h"
#include "nfs_proto.h"
#include "nfs_mount.h"
#include "nfs_node.h"
#include "nfs_socket.h"
#include "xdr_subs.h"
/****************************************************************************
* Private Types
****************************************************************************/
/****************************************************************************
* Private Function Prototypes
****************************************************************************/
/****************************************************************************
* Private Variables
****************************************************************************/
/****************************************************************************
* Public Variables
****************************************************************************/
/****************************************************************************
* Private Functions
****************************************************************************/
static inline int nfs_pathsegment(FAR const char **path, FAR char *buffer,
FAR char *terminator)
{
FAR const char *src = *path;
FAR char *dest = buffer;
int nbytes = 0;
char ch;
/* Loop until the name is successfully parsed or an error occurs */
for (;;)
{
/* Get the next byte from the path */
ch = *src++;
/* Check if this the last byte in this segment name */
if (ch == '\0' || ch == '/')
{
/* This logic just suppors "//" sequences in the path name */
if (ch == '\0' || nbytes > 0 )
{
/* NULL terminate the parsed path segment */
*dest = '\0';
/* Return next path and the terminating character */
*terminator = ch;
*path = src;
return OK;
}
/* Just skip over any leading '/' characters */
}
else if (nbytes >= NAME_MAX)
{
fdbg("File name segment is too long: %d\n", *path);
return EFBIG;
}
else
{
/* Save next character in the accumulated name */
*dest++ = ch;
}
}
}
/****************************************************************************
* Public Functions
****************************************************************************/
/****************************************************************************
* Name: nfs_semtake
****************************************************************************/
void nfs_semtake(struct nfsmount *nmp)
{
/* Take the semaphore (perhaps waiting) */
while (sem_wait(&nmp->nm_sem) != 0)
{
/* The only case that an error should occur here is if
* the wait was awakened by a signal.
*/
ASSERT(*get_errno_ptr() == EINTR);
}
}
/****************************************************************************
* Name: nfs_semgive
****************************************************************************/
void nfs_semgive(struct nfsmount *nmp)
{
sem_post(&nmp->nm_sem);
}
/****************************************************************************
* Name: nfs_checkmount
*
* Desciption: Check if the mountpoint is still valid.
*
* The caller should hold the mountpoint semaphore
*
****************************************************************************/
int nfs_checkmount(struct nfsmount *nmp)
{
struct nfsnode *file;
/* If the nm_mounted flag is false, then we have already handled the loss
* of the mount.
*/
DEBUGASSERT(nmp);
if (!nmp->nm_mounted)
{
/* Make sure that this is flagged in every opened file */
for (file = nmp->nm_head; file; file = file->n_next)
{
file->n_flags &= ~NFSNODE_OPEN;
}
return -ENODEV;
}
return 0;
}
/****************************************************************************
* Name: nfs_fsinfo
*
* Description:
* Return information about root directory.
*
* Returned Value:
* 0 on success; positive errno value on failure
*
* Assumptions:
* The caller has exclusive access to the NFS mount structure
*
****************************************************************************/
int nfs_fsinfo(FAR struct nfsmount *nmp)
{
struct rpc_reply_fsinfo fsp;
struct FS3args fsinfo;
uint32_t pref;
uint32_t max;
int error = 0;
memset(&fsinfo, 0, sizeof(struct FS3args));
memset(&fsp, 0, sizeof(struct rpc_reply_fsinfo));
nfsstats.rpccnt[NFSPROC_FSINFO]++;
fsinfo.fsroot.length = txdr_unsigned(nmp->nm_fhsize);
fsinfo.fsroot.handle = nmp->nm_fh;
/* Request FSINFO from the server */
error = nfs_request(nmp, NFSPROC_FSINFO,
(FAR const void *)&fsinfo, sizeof(struct FS3args),
(FAR void *)&fsp, sizeof(struct rpc_reply_fsinfo));
if (error)
{
return error;
}
/* Save the root file system attributes */
#if 0
memcpy(&nmp->nm_fattr. &fsp.obj_attributes, sizeof(struct nfs_fattr));
#endif
pref = fxdr_unsigned(uint32_t, fsp.fsinfo.fs_wtpref);
if (pref < nmp->nm_wsize)
{
nmp->nm_wsize = (pref + NFS_FABLKSIZE - 1) & ~(NFS_FABLKSIZE - 1);
}
max = fxdr_unsigned(uint32_t, fsp.fsinfo.fs_wtmax);
if (max < nmp->nm_wsize)
{
nmp->nm_wsize = max & ~(NFS_FABLKSIZE - 1);
if (nmp->nm_wsize == 0)
{
nmp->nm_wsize = max;
}
}
pref = fxdr_unsigned(uint32_t, fsp.fsinfo.fs_rtpref);
if (pref < nmp->nm_rsize)
{
nmp->nm_rsize = (pref + NFS_FABLKSIZE - 1) & ~(NFS_FABLKSIZE - 1);
}
max = fxdr_unsigned(uint32_t, fsp.fsinfo.fs_rtmax);
if (max < nmp->nm_rsize)
{
nmp->nm_rsize = max & ~(NFS_FABLKSIZE - 1);
if (nmp->nm_rsize == 0)
{
nmp->nm_rsize = max;
}
}
pref = fxdr_unsigned(uint32_t, fsp.fsinfo.fs_dtpref);
if (pref < nmp->nm_readdirsize)
{
nmp->nm_readdirsize = (pref + NFS_DIRBLKSIZ - 1) & ~(NFS_DIRBLKSIZ - 1);
}
if (max < nmp->nm_readdirsize)
{
nmp->nm_readdirsize = max & ~(NFS_DIRBLKSIZ - 1);
if (nmp->nm_readdirsize == 0)
{
nmp->nm_readdirsize = max;
}
}
nmp->nm_flag |= NFSMNT_GOTFSINFO;
return 0;
}
/****************************************************************************
* Name: nfs_lookup
*
* Desciption:
* Given a directory file handle, and the path to file in the directory,
* return the file handle of the path and attributes of both the file and
* the directory containing the file.
*
* NOTE: The LOOKUP call differs from other RPC messages in that the
* call message is variable length, depending upon the size of the path
* name.
*
****************************************************************************/
int nfs_lookup(struct nfsmount *nmp, FAR const char *filename,
FAR struct file_handle *fhandle,
FAR struct nfs_fattr *obj_attributes,
FAR struct nfs_fattr *dir_attributes)
{
struct LOOKUP3args request;
struct rpc_reply_lookup response;
FAR uint32_t *ptr;
uint32_t value;
int reqlen;
int namelen;
int error = 0;
DEBUGASSERT(nmp && filename && fhandle);
/* Set all of the buffers to a known state */
memset(&request, 0, sizeof(struct LOOKUP3args));
memset(&response, 0, sizeof(struct rpc_reply_lookup));
/* Get the length of the string to be sent */
namelen = strlen(filename);
if (namelen > NAME_MAX)
{
fdbg("Length of \"%s\%too big: %d\n", namelen);
return E2BIG;
}
/* Initialize the request */
ptr = (FAR uint32_t*)&request;
reqlen = 0;
/* Copy the variable length, directory file handle */
*ptr++ = txdr_unsigned(fhandle->length);
reqlen += sizeof(uint32_t);
memcpy(ptr, &fhandle->handle, fhandle->length);
reqlen += fhandle->length;
ptr += uint32_increment(fhandle->length);
/* Copy the variable-length file name */
*ptr++ = txdr_unsigned(namelen);
reqlen += sizeof(uint32_t);
memcpy(ptr, filename, namelen);
reqlen += uint32_alignup(namelen);
/* Request LOOKUP from the server */
nfsstats.rpccnt[NFSPROC_LOOKUP]++;
error = nfs_request(nmp, NFSPROC_LOOKUP,
(FAR const void *)&request, reqlen,
(FAR void *)&response, sizeof(struct rpc_reply_lookup));
if (error)
{
fdbg("ERROR: nfs_request failed: %d\n", error);
return error;
}
/* Return the data to the caller's buffers. NOTE: Here we ignore the
* the exact layout of the rpc_reply_lookup structure. File handles
* may differ in size whereas struct rpc_reply_lookup uses a fixed size.
*/
ptr = (FAR uint32_t*)&response.lookup;
/* Get the length of the file handle */
value = *ptr++;
value = fxdr_unsigned(uint32_t, value);
if (value > NFSX_V2FH)
{
fdbg("ERROR: Bad file handle length: %d\n", value);
return EIO;
}
/* Return the file handle */
fhandle->length = value;
memcpy(&fhandle->handle, ptr, value);
ptr += uint32_increment(value);
/* Check if there are object attributes and, if so, copy them to the user
* buffer
*/
value = *ptr++;
if (value)
{
if (obj_attributes)
{
memcpy(obj_attributes, ptr, sizeof(struct nfs_fattr));
}
ptr += uint32_increment(sizeof(struct nfs_fattr));
}
/* Check if there are directory attributes and, if so, copy them to the
* user buffer
*/
value = *ptr++;
if (value && dir_attributes)
{
memcpy(dir_attributes, ptr, sizeof(struct nfs_fattr));
}
return OK;
}
/****************************************************************************
* Name: nfs_findnode
*
* Desciption:
* Given a path to something that may or may not be in the file system,
* return the handle of the directory entry of the requested item object.
*
* Return Value:
* Zero on success; a positive errno value on failure.
*
****************************************************************************/
int nfs_findnode(struct nfsmount *nmp, FAR const char *relpath,
FAR struct file_handle *fhandle, FAR struct nfs_fattr *obj_attributes,
FAR struct nfs_fattr *dir_attributes)
{
FAR const char *path = relpath;
char buffer[NAME_MAX+1];
char terminator;
int error;
/* Start with the file handle of the root directory. */
fhandle->length = nmp->nm_fhsize;
memcpy(&fhandle->handle, &nmp->nm_fh, sizeof(nfsfh_t));
/* If no path was provided, then the root directory must be exactly what
* the caller is looking for.
*/
if (*path == '\0' || strlen(path) == 0)
{
/* Return the root directory attributes */
if (obj_attributes)
{
memcpy(obj_attributes, &nmp->nm_fattr, sizeof(struct nfs_fattr));
}
if (dir_attributes)
{
memcpy(dir_attributes, &nmp->nm_fattr, sizeof(struct nfs_fattr));
}
return OK;
}
/* This is not the root directory. Loop until the directory entry corresponding
* to the path is found.
*/
for (;;)
{
/* Extract the next path segment name. */
error = nfs_pathsegment(&path, buffer, &terminator);
if (error != 0)
{
/* The filename segment contains is too long. */
fdbg("nfs_pathsegment of \"%s\" failed after \"%s\": %d\n",
relpath, buffer, error);
return error;
}
/* Look-up this path segment */
error = nfs_lookup(nmp, buffer, fhandle, obj_attributes, dir_attributes);
if (error != 0)
{
fdbg("nfs_lookup of \"%s\" failed at \"%s\": %d\n",
relpath, buffer, error);
return error;
}
/* If the terminator character in the path was the end of the string
* then we have successfully found the directory entry that describes
* the path.
*/
if (!terminator)
{
/* Return success meaning that the description the matching
* directory entry is in fhandle, obj_attributes, and dir_attributes.
*/
return OK;
}
/* No.. then we have found one of the intermediate directories on
* the way to the final path target. In this case, make sure
* the thing that we found is, indeed, a directory.
*/
if (obj_attributes->fa_type != NFDIR)
{
/* Ooops.. we found something else */
fdbg("ERROR: Intermediate segment \"%s\" of \'%s\" is not a directory\n",
buffer, path);
return ENOTDIR;
}
}
}
