/* 
   Unix SMB/CIFS implementation.
   file closing
   Copyright (C) Andrew Tridgell 1992-1998
   Copyright (C) Jeremy Allison 1992-2004.
   Copyright (C) Volker Lendecke 2005
   
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2 of the License, or
   (at your option) any later version.
   
   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.
   
   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/

#include "includes.h"

/****************************************************************************
 Run a file if it is a magic script.
****************************************************************************/

static void check_magic(files_struct *fsp,connection_struct *conn)
{
	if (!*lp_magicscript(SNUM(conn)))
		return;

	DEBUG(5,("checking magic for %s\n",fsp->fsp_name));

	{
		char *p;
		if (!(p = strrchr_m(fsp->fsp_name,'/')))
			p = fsp->fsp_name;
		else
			p++;

		if (!strequal(lp_magicscript(SNUM(conn)),p))
			return;
	}

	{
		int ret;
		pstring magic_output;
		pstring fname;
		SMB_STRUCT_STAT st;
		int tmp_fd, outfd;

		pstrcpy(fname,fsp->fsp_name);
		if (*lp_magicoutput(SNUM(conn)))
			pstrcpy(magic_output,lp_magicoutput(SNUM(conn)));
		else
			slprintf(magic_output,sizeof(fname)-1, "%s.out",fname);

		chmod(fname,0755);
		ret = smbrun(fname,&tmp_fd);
		DEBUG(3,("Invoking magic command %s gave %d\n",fname,ret));
		unlink(fname);
		if (ret != 0 || tmp_fd == -1) {
			if (tmp_fd != -1)
				close(tmp_fd);
			return;
		}
		outfd = open(magic_output, O_CREAT|O_EXCL|O_RDWR, 0600);
		if (outfd == -1) {
			close(tmp_fd);
			return;
		}

		if (sys_fstat(tmp_fd,&st) == -1) {
			close(tmp_fd);
			close(outfd);
			return;
		}

		transfer_file(tmp_fd,outfd,(SMB_OFF_T)st.st_size);
		close(tmp_fd);
		close(outfd);
	}
}

/****************************************************************************
  Common code to close a file or a directory.
****************************************************************************/

static int close_filestruct(files_struct *fsp)
{   
	connection_struct *conn = fsp->conn;
	int ret = 0;
    
	if (fsp->fh->fd != -1) {
		if(flush_write_cache(fsp, CLOSE_FLUSH) == -1)
			ret = -1;

		delete_write_cache(fsp);
	}

	conn->num_files_open--;
	SAFE_FREE(fsp->wbmpx_ptr);

	return ret;
}    

/****************************************************************************
 If any deferred opens are waiting on this close, notify them.
****************************************************************************/

static void notify_deferred_opens(struct share_mode_lock *lck)
{
 	int i;
 
 	for (i=0; i<lck->num_share_modes; i++) {
 		struct share_mode_entry *e = &lck->share_modes[i];
 
 		if (!is_deferred_open_entry(e)) {
 			continue;
 		}
 
 		if (procid_is_me(&e->pid)) {
 			/*
 			 * We need to notify ourself to retry the open.  Do
 			 * this by finding the queued SMB record, moving it to
 			 * the head of the queue and changing the wait time to
 			 * zero.
 			 */
 			schedule_deferred_open_smb_message(e->op_mid);
 		} else {
			char msg[MSG_SMB_SHARE_MODE_ENTRY_SIZE];

			share_mode_entry_to_message(msg, e);

			become_root();
 			message_send_pid(e->pid, MSG_SMB_OPEN_RETRY,
 					 msg, MSG_SMB_SHARE_MODE_ENTRY_SIZE, True);
			unbecome_root();
 		}
 	}
}

/****************************************************************************
 Deal with removing a share mode on last close.
****************************************************************************/

static int close_remove_share_mode(files_struct *fsp, enum file_close_type close_type)
{
	connection_struct *conn = fsp->conn;
	BOOL delete_file = False;
	struct share_mode_lock *lck;

	/*
	 * Lock the share entries, and determine if we should delete
	 * on close. If so delete whilst the lock is still in effect.
	 * This prevents race conditions with the file being created. JRA.
	 */

	lck = get_share_mode_lock(NULL, fsp->dev, fsp->inode, NULL, NULL);

	if (lck == NULL) {
		DEBUG(0, ("close_remove_share_mode: Could not get share mode lock for file %s\n", fsp->fsp_name));
		return EINVAL;
	}

	if (!del_share_mode(lck, fsp)) {
		DEBUG(0, ("close_remove_share_mode: Could not delete share entry for file %s\n", fsp->fsp_name));
	}

	delete_file = (lck->delete_on_close | lck->initial_delete_on_close);

	if (delete_file) {
		int i;
		/* See if others still have the file open. If this is the
		 * case, then don't delete */
		for (i=0; i<lck->num_share_modes; i++) {
			if (is_valid_share_mode_entry(&lck->share_modes[i])) {
				delete_file = False;
				break;
			}
		}
	}

	/* Notify any deferred opens waiting on this close. */
	notify_deferred_opens(lck);
	reply_to_oplock_break_requests(fsp);

	/*
	 * NT can set delete_on_close of the last open
	 * reference to a file.
	 */

	if ((close_type == NORMAL_CLOSE || close_type == SHUTDOWN_CLOSE) &&
				delete_file &&
				lck->delete_token) {
		SMB_STRUCT_STAT sbuf;

		DEBUG(5,("close_remove_share_mode: file %s. Delete on close was set - deleting file.\n",
			fsp->fsp_name));

		/* Become the user who requested the delete. */

		if (!push_sec_ctx()) {
			smb_panic("close_remove_share_mode: file %s. failed to push sec_ctx.\n");
		}

		set_sec_ctx(lck->delete_token->uid,
				lck->delete_token->gid,
				lck->delete_token->ngroups,
				lck->delete_token->groups,
				NULL);

		/* We can only delete the file if the name we have
		   is still valid and hasn't been renamed. */
	
		if(SMB_VFS_STAT(conn,fsp->fsp_name,&sbuf) != 0) {
			DEBUG(5,("close_remove_share_mode: file %s. Delete on close was set "
				"and stat failed with error %s\n",
				fsp->fsp_name, strerror(errno) ));
		} else {
			if(sbuf.st_dev != fsp->dev || sbuf.st_ino != fsp->inode) {
				DEBUG(5,("close_remove_share_mode: file %s. Delete on close was set and "
					"dev and/or inode does not match\n",
					fsp->fsp_name ));
				DEBUG(5,("close_remove_share_mode: file %s. stored dev = %x, inode = %.0f "
					"stat dev = %x, inode = %.0f\n",
					fsp->fsp_name,
					(unsigned int)fsp->dev, (double)fsp->inode,
					(unsigned int)sbuf.st_dev, (double)sbuf.st_ino ));

			} else if(SMB_VFS_UNLINK(conn,fsp->fsp_name) != 0) {
				/*
				 * This call can potentially fail as another smbd may have
				 * had the file open with delete on close set and deleted
				 * it when its last reference to this file went away. Hence
				 * we log this but not at debug level zero.
				 */

				DEBUG(5,("close_remove_share_mode: file %s. Delete on close was set "
					"and unlink failed with error %s\n",
					fsp->fsp_name, strerror(errno) ));
			}
		}
		/* unbecome user. */
		pop_sec_ctx();
	
		process_pending_change_notify_queue((time_t)0);
	}

	TALLOC_FREE(lck);
	return 0;
}

/****************************************************************************
 Close a file.

 close_type can be NORMAL_CLOSE=0,SHUTDOWN_CLOSE,ERROR_CLOSE.
 printing and magic scripts are only run on normal close.
 delete on close is done on normal and shutdown close.
****************************************************************************/

static int close_normal_file(files_struct *fsp, enum file_close_type close_type)
{
	connection_struct *conn = fsp->conn;
	int saved_errno = 0;
	int err = 0;
	int err1 = 0;

	remove_pending_lock_requests_by_fid(fsp);

	if (fsp->aio_write_behind) {
		/*
	 	 * If we're finishing write behind on a close we can get a write
		 * error here, we must remember this.
		 */
		int ret = wait_for_aio_completion(fsp);
		if (ret) {
			saved_errno = ret;
			err1 = -1;
		}
	} else {
		cancel_aio_by_fsp(fsp);
	}
 
	/*
	 * If we're flushing on a close we can get a write
	 * error here, we must remember this.
	 */

	if (close_filestruct(fsp) == -1) {
		saved_errno = errno;
		err1 = -1;
	}

	if (fsp->print_file) {
		print_fsp_end(fsp, close_type);
		file_free(fsp);
		return 0;
	}

	/* If this is an old DOS or FCB open and we have multiple opens on
	   the same handle we only have one share mode. Ensure we only remove
	   the share mode on the last close. */

	if (fsp->fh->ref_count == 1) {
		/* Should we return on error here... ? */
		close_remove_share_mode(fsp, close_type);
	}

	if(fsp->oplock_type) {
		release_file_oplock(fsp);
	}

	locking_close_file(fsp);

	err = fd_close(conn, fsp);

	/* Only save errno if fd_close failed and we don't already
	   have an errno saved from a flush call. */
	if ((err1 != -1) && (err == -1)) {
		saved_errno = errno;
	}

	/* check for magic scripts */
	if (close_type == NORMAL_CLOSE) {
		check_magic(fsp,conn);
	}

	/*
	 * Ensure pending modtime is set after close.
	 */

	if(fsp->pending_modtime && fsp->pending_modtime_owner) {
		set_filetime(conn, fsp->fsp_name, fsp->pending_modtime);
	} else if (fsp->last_write_time) {
		set_filetime(conn, fsp->fsp_name, fsp->last_write_time);
	}

	DEBUG(2,("%s closed file %s (numopen=%d) %s\n",
		conn->user,fsp->fsp_name,
		conn->num_files_open,
		(err == -1 || err1 == -1) ? strerror(saved_errno) : ""));

	file_free(fsp);

	if (err == -1 || err1 == -1) {
		errno = saved_errno;
		return saved_errno;
	} else {
		return 0;
	}
}

/****************************************************************************
 Close a directory opened by an NT SMB call. 
****************************************************************************/
  
static int close_directory(files_struct *fsp, enum file_close_type close_type)
{
	struct share_mode_lock *lck = 0;
	BOOL delete_dir = False;

	/*
	 * NT can set delete_on_close of the last open
	 * reference to a directory also.
	 */

	lck = get_share_mode_lock(NULL, fsp->dev, fsp->inode, NULL, NULL);

	if (lck == NULL) {
		DEBUG(0, ("close_directory: Could not get share mode lock for %s\n", fsp->fsp_name));
		return EINVAL;
	}

	if (!del_share_mode(lck, fsp)) {
		DEBUG(0, ("close_directory: Could not delete share entry for %s\n", fsp->fsp_name));
	}

	delete_dir = (lck->delete_on_close | lck->initial_delete_on_close);

	if ((close_type == NORMAL_CLOSE || close_type == SHUTDOWN_CLOSE) &&
				delete_dir &&
				lck->delete_token) {
		BOOL ok;
	
		/* Become the user who requested the delete. */

		if (!push_sec_ctx()) {
			smb_panic("close_directory: failed to push sec_ctx.\n");
		}

		set_sec_ctx(lck->delete_token->uid,
				lck->delete_token->gid,
				lck->delete_token->ngroups,
				lck->delete_token->groups,
				NULL);

		TALLOC_FREE(lck);

		ok = rmdir_internals(fsp->conn, fsp->fsp_name);

		DEBUG(5,("close_directory: %s. Delete on close was set - deleting directory %s.\n",
			fsp->fsp_name, ok ? "succeeded" : "failed" ));

		/* unbecome user. */
		pop_sec_ctx();

		/*
		 * Ensure we remove any change notify requests that would
		 * now fail as the directory has been deleted.
		 */

		if(ok) {
			remove_pending_change_notify_requests_by_fid(fsp, NT_STATUS_DELETE_PENDING);
			remove_pending_change_notify_requests_by_filename(fsp, NT_STATUS_DELETE_PENDING);

		}
		process_pending_change_notify_queue((time_t)0);
	} else {
		TALLOC_FREE(lck);
		remove_pending_change_notify_requests_by_fid(fsp, NT_STATUS_CANCELLED);
	}

	/*
	 * Do the code common to files and directories.
	 */
	close_filestruct(fsp);
	file_free(fsp);
	return 0;
}

/****************************************************************************
 Close a 'stat file' opened internally.
****************************************************************************/
  
static int close_stat(files_struct *fsp)
{
	/*
	 * Do the code common to files and directories.
	 */
	close_filestruct(fsp);
	file_free(fsp);
	return 0;
}

/****************************************************************************
 Close a files_struct.
****************************************************************************/
  
int close_file(files_struct *fsp, enum file_close_type close_type)
{
	if(fsp->is_directory)
		return close_directory(fsp, close_type);
	else if (fsp->is_stat)
		return close_stat(fsp);
	else if (fsp->fake_file_handle != NULL)
		return close_fake_file(fsp);
	else
		return close_normal_file(fsp, close_type);
}