hadoop-hdfs-project/hadoop-hdfs-native-client/src/main/native/fuse-dfs/fuse_impls_getattr.c

/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include "fuse_dfs.h"
#include "fuse_impls.h"
#include "fuse_stat_struct.h"
#include "fuse_connect.h"

int dfs_getattr(const char *path, struct stat *st)
{
  struct hdfsConn *conn = NULL;
  hdfsFS fs;
  int ret;
  hdfsFileInfo *info;

  TRACE1("getattr", path)
  dfs_context *dfs = (dfs_context*)fuse_get_context()->private_data;
  assert(dfs);
  assert(path);
  assert(st);

  ret = fuseConnectAsThreadUid(&conn);
  if (ret) {
    fprintf(stderr, "fuseConnectAsThreadUid: failed to open a libhdfs "
            "connection!  error %d.\n", ret);
    ret = -EIO;
    goto cleanup;
  }
  fs = hdfsConnGetFs(conn);
  
  info = hdfsGetPathInfo(fs,path);
  if (NULL == info) {
    ret = -ENOENT;
    goto cleanup;
  }
  fill_stat_structure(&info[0], st);

  // setup hard link info - for a file it is 1 else num entries in a dir + 2 (for . and ..)
  if (info[0].mKind == kObjectKindDirectory) {
    int numEntries = 0;
    hdfsFileInfo *info = hdfsListDirectory(fs,path,&numEntries);

    if (info) {
      hdfsFreeFileInfo(info,numEntries);
    }
    st->st_nlink = numEntries + 2;
  } else {
    // not a directory
    st->st_nlink = 1;
  }

  // free the info pointer
  hdfsFreeFileInfo(info,1);

cleanup:
  if (conn) {
    hdfsConnRelease(conn);
  }
  return ret;
}