fuse_trash.c
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上传日期:2018-01-08
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文件大小:4k
- /**
- * 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 <hdfs.h>
- #include <strings.h>
- #include "fuse_dfs.h"
- #include "fuse_trash.h"
- #include "fuse_context_handle.h"
- const char *const TrashPrefixDir = "/user/root/.Trash";
- const char *const TrashDir = "/user/root/.Trash/Current";
- #define TRASH_RENAME_TRIES 100
- //
- // NOTE: this function is a c implementation of org.apache.hadoop.fs.Trash.moveToTrash(Path path).
- //
- int move_to_trash(const char *item, hdfsFS userFS) {
- // retrieve dfs specific data
- dfs_context *dfs = (dfs_context*)fuse_get_context()->private_data;
- // check params and the context var
- assert(item);
- assert(dfs);
- assert('/' == *item);
- assert(rindex(item,'/') >= 0);
- char fname[4096]; // or last element of the directory path
- char parent_directory[4096]; // the directory the fname resides in
- if (strlen(item) > sizeof(fname) - strlen(TrashDir)) {
- syslog(LOG_ERR, "ERROR: internal buffer too small to accomodate path of length %d %s:%dn", (int)strlen(item), __FILE__, __LINE__);
- return -EIO;
- }
- // separate the file name and the parent directory of the item to be deleted
- {
- int length_of_parent_dir = rindex(item, '/') - item ;
- int length_of_fname = strlen(item) - length_of_parent_dir - 1; // the '/'
- // note - the below strncpys should be safe from overflow because of the check on item's string length above.
- strncpy(parent_directory, item, length_of_parent_dir);
- parent_directory[length_of_parent_dir ] = 0;
- strncpy(fname, item + length_of_parent_dir + 1, strlen(item));
- fname[length_of_fname + 1] = 0;
- }
- // create the target trash directory
- char trash_dir[4096];
- if (snprintf(trash_dir, sizeof(trash_dir), "%s%s",TrashDir,parent_directory) >= sizeof trash_dir) {
- syslog(LOG_ERR, "move_to_trash error target is not big enough to hold new name for %s %s:%dn",item, __FILE__, __LINE__);
- return -EIO;
- }
- // create the target trash directory in trash (if needed)
- if ( hdfsExists(userFS, trash_dir)) {
- // make the directory to put it in in the Trash - NOTE
- // hdfsCreateDirectory also creates parents, so Current will be created if it does not exist.
- if (hdfsCreateDirectory(userFS, trash_dir)) {
- return -EIO;
- }
- }
- //
- // if the target path in Trash already exists, then append with
- // a number. Start from 1.
- //
- char target[4096];
- int j ;
- if ( snprintf(target, sizeof target,"%s/%s",trash_dir, fname) >= sizeof target) {
- syslog(LOG_ERR, "move_to_trash error target is not big enough to hold new name for %s %s:%dn",item, __FILE__, __LINE__);
- return -EIO;
- }
- // NOTE: this loop differs from the java version by capping the #of tries
- for (j = 1; ! hdfsExists(userFS, target) && j < TRASH_RENAME_TRIES ; j++) {
- if (snprintf(target, sizeof target,"%s/%s.%d",trash_dir, fname, j) >= sizeof target) {
- syslog(LOG_ERR, "move_to_trash error target is not big enough to hold new name for %s %s:%dn",item, __FILE__, __LINE__);
- return -EIO;
- }
- }
- if (hdfsRename(userFS, item, target)) {
- syslog(LOG_ERR,"ERROR: hdfs trying to rename %s to %s",item, target);
- return -EIO;
- }
- return 0;
- }
- int hdfsDeleteWithTrash(hdfsFS userFS, const char *path, int useTrash) {
- // move the file to the trash if this is enabled and its not actually in the trash.
- if (useTrash && strncmp(path, TrashPrefixDir, strlen(TrashPrefixDir)) != 0) {
- int ret= move_to_trash(path, userFS);
- return ret;
- }
- if (hdfsDelete(userFS, path)) {
- syslog(LOG_ERR,"ERROR: hdfs trying to delete the file %s",path);
- return -EIO;
- }
- return 0;
- }