163 lines
3.9 KiB
C
163 lines
3.9 KiB
C
/****************************************************************************
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* fs/shm/shm_unlink.c
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*
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* Licensed to the Apache Software Foundation (ASF) under one or more
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* contributor license agreements. See the NOTICE file distributed with
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* this work for additional information regarding copyright ownership. The
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* ASF licenses this file to you under the Apache License, Version 2.0 (the
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* "License"); you may not use this file except in compliance with the
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* License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
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* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
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* License for the specific language governing permissions and limitations
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* under the License.
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*
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****************************************************************************/
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/****************************************************************************
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* Included Files
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****************************************************************************/
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#include <stdio.h>
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#include <assert.h>
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#include <errno.h>
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#include "inode/inode.h"
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/****************************************************************************
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* Private Functions
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****************************************************************************/
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static int file_shm_unlink(FAR const char *name)
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{
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FAR struct inode *inode;
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struct inode_search_s desc;
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char fullpath[sizeof(CONFIG_FS_SHMFS_VFS_PATH) + CONFIG_NAME_MAX + 2];
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int ret;
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/* Make sure that a non-NULL name is supplied */
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if (!name)
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{
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return -ENOENT;
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}
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/* Remove any number of leading '/' */
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while (*name == '/')
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{
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name++;
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}
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/* Empty name supplied? */
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if (*name == '\0')
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{
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return -ENOENT;
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}
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/* Name too long? */
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if (strnlen(name, CONFIG_NAME_MAX + 1) > CONFIG_NAME_MAX)
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{
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return -ENAMETOOLONG;
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}
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/* Get the full path to the shm object */
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snprintf(fullpath, sizeof(fullpath),
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CONFIG_FS_SHMFS_VFS_PATH "/%s", name);
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/* Get the inode for this shm object */
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SETUP_SEARCH(&desc, fullpath, false);
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ret = inode_lock();
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if (ret < 0)
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{
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goto errout_with_search;
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}
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ret = inode_find(&desc);
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if (ret < 0)
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{
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/* There is no inode that includes in this path */
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goto errout_with_sem;
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}
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/* Get the search results */
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inode = desc.node;
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DEBUGASSERT(inode != NULL);
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/* Verify that what we found is, indeed, an shm inode */
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if (!INODE_IS_SHM(inode))
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{
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ret = -ENOENT;
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goto errout_with_inode;
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}
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#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
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if (inode->u.i_ops->unlink)
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{
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/* Notify the shmfs driver that it has been unlinked */
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ret = inode->u.i_ops->unlink(inode);
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if (ret < 0)
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{
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goto errout_with_inode;
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}
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}
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#endif
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/* Remove the old inode from the tree. If we hold a reference count
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* on the inode, it will not be deleted now. This will set the
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* FSNODEFLAG_DELETED bit in the inode flags.
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*/
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ret = inode_remove(fullpath);
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/* inode_remove() should always fail with -EBUSY because we have a
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* reference on the inode. -EBUSY means that the inode was, indeed,
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* unlinked but it could not be freed because there are references.
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*/
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if (ret == -EBUSY)
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{
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ret = OK;
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}
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DEBUGASSERT(ret == OK);
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errout_with_inode:
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inode_release(inode);
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errout_with_sem:
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inode_unlock();
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errout_with_search:
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RELEASE_SEARCH(&desc);
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return ret;
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}
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/****************************************************************************
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* Public Functions
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****************************************************************************/
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int shm_unlink(FAR const char *name)
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{
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int ret = file_shm_unlink(name);
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if (ret < 0)
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{
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set_errno(-ret);
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return -1;
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}
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return 0;
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}
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