vfs-wrap.c

samba-3.0.22.tar.gz 编译smb服务器的源码

/* 
   Unix SMB/CIFS implementation.
   Wrap disk only vfs functions to sidestep dodgy compilers.
   Copyright (C) Tim Potter 1998
   
   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"

#undef DBGC_CLASS
#define DBGC_CLASS DBGC_VFS


/* Check for NULL pointer parameters in vfswrap_* functions */

/* We don't want to have NULL function pointers lying around.  Someone
   is sure to try and execute them.  These stubs are used to prevent
   this possibility. */

int vfswrap_dummy_connect(vfs_handle_struct *handle, connection_struct *conn, const char *service, const char *user)
{
    return 0;    /* Return >= 0 for success */
}

void vfswrap_dummy_disconnect(vfs_handle_struct *handle, connection_struct *conn)
{
}

/* Disk operations */

SMB_BIG_UINT vfswrap_disk_free(vfs_handle_struct *handle, connection_struct *conn, const char *path, BOOL small_query, SMB_BIG_UINT *bsize, 
			       SMB_BIG_UINT *dfree, SMB_BIG_UINT *dsize)
{
	SMB_BIG_UINT result;

	result = sys_disk_free(conn, path, small_query, bsize, dfree, dsize);
	return result;
}

int vfswrap_get_quota(struct vfs_handle_struct *handle, struct connection_struct *conn, enum SMB_QUOTA_TYPE qtype, unid_t id, SMB_DISK_QUOTA *qt)
{
#ifdef HAVE_SYS_QUOTAS
	int result;

	START_PROFILE(syscall_get_quota);
	result = sys_get_quota(conn->connectpath, qtype, id, qt);
	END_PROFILE(syscall_get_quota);
	return result;
#else
	errno = ENOSYS;
	return -1;
#endif	
}

int vfswrap_set_quota(struct vfs_handle_struct *handle, struct connection_struct *conn, enum SMB_QUOTA_TYPE qtype, unid_t id, SMB_DISK_QUOTA *qt)
{
#ifdef HAVE_SYS_QUOTAS
	int result;

	START_PROFILE(syscall_set_quota);
	result = sys_set_quota(conn->connectpath, qtype, id, qt);
	END_PROFILE(syscall_set_quota);
	return result;
#else
	errno = ENOSYS;
	return -1;
#endif	
}

int vfswrap_get_shadow_copy_data(struct vfs_handle_struct *handle, struct files_struct *fsp, SHADOW_COPY_DATA *shadow_copy_data, BOOL labels)
{
	errno = ENOSYS;
	return -1;  /* Not implemented. */
}
    
int vfswrap_statvfs(struct vfs_handle_struct *handle, struct connection_struct *conn, const char *path, vfs_statvfs_struct *statbuf)
{
	return sys_statvfs(path, statbuf);
}

/* Directory operations */

SMB_STRUCT_DIR *vfswrap_opendir(vfs_handle_struct *handle, connection_struct *conn, const char *fname, const char *mask, uint32 attr)
{
	SMB_STRUCT_DIR *result;

	START_PROFILE(syscall_opendir);
	result = sys_opendir(fname);
	END_PROFILE(syscall_opendir);
	return result;
}

SMB_STRUCT_DIRENT *vfswrap_readdir(vfs_handle_struct *handle, connection_struct *conn, SMB_STRUCT_DIR *dirp)
{
	SMB_STRUCT_DIRENT *result;

	START_PROFILE(syscall_readdir);
	result = sys_readdir(dirp);
	END_PROFILE(syscall_readdir);
	return result;
}

void vfswrap_seekdir(vfs_handle_struct *handle, connection_struct *conn, SMB_STRUCT_DIR *dirp, long offset)
{
	START_PROFILE(syscall_seekdir);
	sys_seekdir(dirp, offset);
	END_PROFILE(syscall_seekdir);
}

long vfswrap_telldir(vfs_handle_struct *handle, connection_struct *conn, SMB_STRUCT_DIR *dirp)
{
	long result;
	START_PROFILE(syscall_telldir);
	result = sys_telldir(dirp);
	END_PROFILE(syscall_telldir);
	return result;
}

void vfswrap_rewinddir(vfs_handle_struct *handle, connection_struct *conn, SMB_STRUCT_DIR *dirp)
{
	START_PROFILE(syscall_rewinddir);
	sys_rewinddir(dirp);
	END_PROFILE(syscall_rewinddir);
}

int vfswrap_mkdir(vfs_handle_struct *handle, connection_struct *conn, const char *path, mode_t mode)
{
	int result;
	BOOL has_dacl = False;

	START_PROFILE(syscall_mkdir);

	if (lp_inherit_acls(SNUM(conn)) && (has_dacl = directory_has_default_acl(conn, parent_dirname(path))))
		mode = 0777;

	result = mkdir(path, mode);

	if (result == 0 && !has_dacl) {
		/*
		 * We need to do this as the default behavior of POSIX ACLs	
		 * is to set the mask to be the requested group permission
		 * bits, not the group permission bits to be the requested
		 * group permission bits. This is not what we want, as it will
		 * mess up any inherited ACL bits that were set. JRA.
		 */
		int saved_errno = errno; /* We may get ENOSYS */
		if ((SMB_VFS_CHMOD_ACL(conn, path, mode) == -1) && (errno == ENOSYS))
			errno = saved_errno;
	}

	END_PROFILE(syscall_mkdir);
	return result;
}

int vfswrap_rmdir(vfs_handle_struct *handle, connection_struct *conn, const char *path)
{
	int result;

	START_PROFILE(syscall_rmdir);
	result = rmdir(path);
	END_PROFILE(syscall_rmdir);
	return result;
}

int vfswrap_closedir(vfs_handle_struct *handle, connection_struct *conn, SMB_STRUCT_DIR *dirp)
{
	int result;

	START_PROFILE(syscall_closedir);
	result = sys_closedir(dirp);
	END_PROFILE(syscall_closedir);
	return result;
}

/* File operations */
    
int vfswrap_open(vfs_handle_struct *handle, connection_struct *conn, const char *fname, int flags, mode_t mode)
{
	int result;

	START_PROFILE(syscall_open);
	result = sys_open(fname, flags, mode);
	END_PROFILE(syscall_open);
	return result;
}

int vfswrap_close(vfs_handle_struct *handle, files_struct *fsp, int fd)
{
	int result;

	START_PROFILE(syscall_close);

	result = close(fd);
	END_PROFILE(syscall_close);
	return result;
}

ssize_t vfswrap_read(vfs_handle_struct *handle, files_struct *fsp, int fd, void *data, size_t n)
{
	ssize_t result;

	START_PROFILE_BYTES(syscall_read, n);
	result = sys_read(fd, data, n);
	END_PROFILE(syscall_read);
	return result;
}

ssize_t vfswrap_pread(vfs_handle_struct *handle, files_struct *fsp, int fd, void *data,
			size_t n, SMB_OFF_T offset)
{
	ssize_t result;

#if defined(HAVE_PREAD) || defined(HAVE_PREAD64)
	START_PROFILE_BYTES(syscall_pread, n);
	result = sys_pread(fd, data, n, offset);
	END_PROFILE(syscall_pread);
 
	if (result == -1 && errno == ESPIPE) {
		/* Maintain the fiction that pipes can be seeked (sought?) on. */
		result = SMB_VFS_READ(fsp, fd, data, n);
		fsp->fh->pos = 0;
	}

#else /* HAVE_PREAD */
	SMB_OFF_T   curr;
	int lerrno;
   
	curr = SMB_VFS_LSEEK(fsp, fd, 0, SEEK_CUR);
	if (curr == -1 && errno == ESPIPE) {
		/* Maintain the fiction that pipes can be seeked (sought?) on. */
		result = SMB_VFS_READ(fsp, fd, data, n);
		fsp->fh->pos = 0;
		return result;
	}

	if (SMB_VFS_LSEEK(fsp, fd, offset, SEEK_SET) == -1) {
		return -1;
	}

	errno = 0;
	result = SMB_VFS_READ(fsp, fd, data, n);
	lerrno = errno;

	SMB_VFS_LSEEK(fsp, fd, curr, SEEK_SET);
	errno = lerrno;

#endif /* HAVE_PREAD */

	return result;
}

ssize_t vfswrap_write(vfs_handle_struct *handle, files_struct *fsp, int fd, const void *data, size_t n)
{
	ssize_t result;

	START_PROFILE_BYTES(syscall_write, n);
	result = sys_write(fd, data, n);
	END_PROFILE(syscall_write);
	return result;
}

ssize_t vfswrap_pwrite(vfs_handle_struct *handle, files_struct *fsp, int fd, const void *data,
			size_t n, SMB_OFF_T offset)
{
	ssize_t result;

#if defined(HAVE_PWRITE) || defined(HAVE_PRWITE64)
	START_PROFILE_BYTES(syscall_pwrite, n);
	result = sys_pwrite(fd, data, n, offset);
	END_PROFILE(syscall_pwrite);

	if (result == -1 && errno == ESPIPE) {
		/* Maintain the fiction that pipes can be sought on. */
		result = SMB_VFS_WRITE(fsp, fd, data, n);
	}

#else /* HAVE_PWRITE */
	SMB_OFF_T   curr;
	int         lerrno;

	curr = SMB_VFS_LSEEK(fsp, fd, 0, SEEK_CUR);
	if (curr == -1) {
		return -1;
	}

	if (SMB_VFS_LSEEK(fsp, fd, offset, SEEK_SET) == -1) {
		return -1;
	}

	result = SMB_VFS_WRITE(fsp, fd, data, n);
	lerrno = errno;

	SMB_VFS_LSEEK(fsp, fd, curr, SEEK_SET);
	errno = lerrno;

#endif /* HAVE_PWRITE */

	return result;
}

SMB_OFF_T vfswrap_lseek(vfs_handle_struct *handle, files_struct *fsp, int filedes, SMB_OFF_T offset, int whence)
{
	SMB_OFF_T result = 0;

	START_PROFILE(syscall_lseek);

	/* Cope with 'stat' file opens. */
	if (filedes != -1)
		result = sys_lseek(filedes, offset, whence);

	/*
	 * We want to maintain the fiction that we can seek
	 * on a fifo for file system purposes. This allows
	 * people to set up UNIX fifo's that feed data to Windows
	 * applications. JRA.
	 */

	if((result == -1) && (errno == ESPIPE)) {
		result = 0;
		errno = 0;
	}

	END_PROFILE(syscall_lseek);
	return result;
}

ssize_t vfswrap_sendfile(vfs_handle_struct *handle, int tofd, files_struct *fsp, int fromfd, const DATA_BLOB *hdr,
			SMB_OFF_T offset, size_t n)
{
	ssize_t result;

	START_PROFILE_BYTES(syscall_sendfile, n);
	result = sys_sendfile(tofd, fromfd, hdr, offset, n);
	END_PROFILE(syscall_sendfile);
	return result;
}

/*********************************************************
 For rename across filesystems Patch from Warren Birnbaum
 <[e-mail]>
**********************************************************/

static int copy_reg(const char *source, const char *dest)
{
	SMB_STRUCT_STAT source_stats;
	int saved_errno;
	int ifd = -1;
	int ofd = -1;

	if (sys_lstat (source, &source_stats) == -1)
		return -1;

	if (!S_ISREG (source_stats.st_mode))
		return -1;

	if((ifd = sys_open (source, O_RDONLY, 0)) < 0)
		return -1;

	if (unlink (dest) && errno != ENOENT)
		return -1;

#ifdef O_NOFOLLOW
	if((ofd = sys_open (dest, O_WRONLY | O_CREAT | O_TRUNC | O_NOFOLLOW, 0600)) < 0 )
#else
	if((ofd = sys_open (dest, O_WRONLY | O_CREAT | O_TRUNC , 0600)) < 0 )
#endif
		goto err;

	if (transfer_file(ifd, ofd, (size_t)-1) == -1)
		goto err;

	/*
	 * Try to preserve ownership.  For non-root it might fail, but that's ok.
	 * But root probably wants to know, e.g. if NFS disallows it.
	 */

#ifdef HAVE_FCHOWN
	if ((fchown(ofd, source_stats.st_uid, source_stats.st_gid) == -1) && (errno != EPERM))
#else
	if ((chown(dest, source_stats.st_uid, source_stats.st_gid) == -1) && (errno != EPERM))
#endif
		goto err;

	/*
	 * fchown turns off set[ug]id bits for non-root,
	 * so do the chmod last.
	 */

#if defined(HAVE_FCHMOD)
	if (fchmod (ofd, source_stats.st_mode & 07777))
#else
	if (chmod (dest, source_stats.st_mode & 07777))
#endif
		goto err;

	if (close (ifd) == -1)
		goto err;

	if (close (ofd) == -1)
		return -1;

	/* Try to copy the old file's modtime and access time.  */
	{
		struct utimbuf tv;

		tv.actime = source_stats.st_atime;
		tv.modtime = source_stats.st_mtime;
		utime(dest, &tv);
	}

	if (unlink (source) == -1)
		return -1;

	return 0;

  err:

	saved_errno = errno;
	if (ifd != -1)
		close(ifd);
	if (ofd != -1)
		close(ofd);
	errno = saved_errno;
	return -1;
}

int vfswrap_rename(vfs_handle_struct *handle, connection_struct *conn, const char *oldname, const char *newname)
{
	int result;

	START_PROFILE(syscall_rename);
	result = rename(oldname, newname);
	if (errno == EXDEV) {
		/* Rename across filesystems needed. */
		result = copy_reg(oldname, newname);
	}

	END_PROFILE(syscall_rename);
	return result;
}

int vfswrap_fsync(vfs_handle_struct *handle, files_struct *fsp, int fd)
{
#ifdef HAVE_FSYNC
	int result;

	START_PROFILE(syscall_fsync);
	result = fsync(fd);
	END_PROFILE(syscall_fsync);
	return result;
#else
	return 0;
#endif
}

int vfswrap_stat(vfs_handle_struct *handle, connection_struct *conn, const char *fname, SMB_STRUCT_STAT *sbuf)
{
	int result;

	START_PROFILE(syscall_stat);
	result = sys_stat(fname, sbuf);
	END_PROFILE(syscall_stat);
	return result;
}

int vfswrap_fstat(vfs_handle_struct *handle, files_struct *fsp, int fd, SMB_STRUCT_STAT *sbuf)
{
	int result;

	START_PROFILE(syscall_fstat);
	result = sys_fstat(fd, sbuf);
	END_PROFILE(syscall_fstat);
	return result;
}

int vfswrap_lstat(vfs_handle_struct *handle, connection_struct *conn, const char *path, SMB_STRUCT_STAT *sbuf)
{
	int result;

	START_PROFILE(syscall_lstat);
	result = sys_lstat(path, sbuf);
	END_PROFILE(syscall_lstat);
	return result;
}

int vfswrap_unlink(vfs_handle_struct *handle, connection_struct *conn, const char *path)
{
	int result;

	START_PROFILE(syscall_unlink);
	result = unlink(path);
	END_PROFILE(syscall_unlink);
	return result;
}

int vfswrap_chmod(vfs_handle_struct *handle, connection_struct *conn, const char *path, mode_t mode)
{
	int result;

	START_PROFILE(syscall_chmod);

	/*
	 * We need to do this due to the fact that the default POSIX ACL
	 * chmod modifies the ACL *mask* for the group owner, not the
	 * group owner bits directly. JRA.
	 */

	
	{
		int saved_errno = errno; /* We might get ENOSYS */
		if ((result = SMB_VFS_CHMOD_ACL(conn, path, mode)) == 0) {
			END_PROFILE(syscall_chmod);
			return result;
		}
		/* Error - return the old errno. */
		errno = saved_errno;
	}

	result = chmod(path, mode);
	END_PROFILE(syscall_chmod);
	return result;
}

int vfswrap_fchmod(vfs_handle_struct *handle, files_struct *fsp, int fd, mode_t mode)
{
	int result;
	
	START_PROFILE(syscall_fchmod);

	/*
	 * We need to do this due to the fact that the default POSIX ACL
	 * chmod modifies the ACL *mask* for the group owner, not the
	 * group owner bits directly. JRA.
	 */