import ext2fs lib to prep for new e2fsprogs

2005-05-09 22:10:42 +00:00
parent b32011943a
commit 1fd98e039d
82 changed files with 17575 additions and 0 deletions
--- a/e2fsprogs/ext2fs/link.c
+++ b/e2fsprogs/ext2fs/link.c
@ -0,0 +1,134 @@
+/*
+ * link.c --- create links in a ext2fs directory
+ * 
+ * Copyright (C) 1993, 1994 Theodore Ts'o.
+ *
+ * %Begin-Header%
+ * This file may be redistributed under the terms of the GNU Public
+ * License.
+ * %End-Header%
+ */
+
+#include <stdio.h>
+#include <string.h>
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#include "ext2_fs.h"
+#include "ext2fs.h"
+
+struct link_struct  {
+	const char	*name;
+	int		namelen;
+	ext2_ino_t	inode;
+	int		flags;
+	int		done;
+	struct ext2_super_block *sb;
+};	
+
+static int link_proc(struct ext2_dir_entry *dirent,
+		     int	offset,
+		     int	blocksize,
+		     char	*buf,
+		     void	*priv_data)
+{
+	struct link_struct *ls = (struct link_struct *) priv_data;
+	struct ext2_dir_entry *next;
+	int rec_len, min_rec_len;
+	int ret = 0;
+
+	rec_len = EXT2_DIR_REC_LEN(ls->namelen);
+
+	/*
+	 * See if the following directory entry (if any) is unused;
+	 * if so, absorb it into this one.
+	 */
+	next = (struct ext2_dir_entry *) (buf + offset + dirent->rec_len);
+	if ((offset + dirent->rec_len < blocksize - 8) &&
+	    (next->inode == 0) &&
+	    (offset + dirent->rec_len + next->rec_len <= blocksize)) {
+		dirent->rec_len += next->rec_len;
+		ret = DIRENT_CHANGED;
+	}
+
+	/*
+	 * If the directory entry is used, see if we can split the
+	 * directory entry to make room for the new name.  If so,
+	 * truncate it and return.
+	 */
+	if (dirent->inode) {
+		min_rec_len = EXT2_DIR_REC_LEN(dirent->name_len & 0xFF);
+		if (dirent->rec_len < (min_rec_len + rec_len))
+			return ret;
+		rec_len = dirent->rec_len - min_rec_len;
+		dirent->rec_len = min_rec_len;
+		next = (struct ext2_dir_entry *) (buf + offset +
+						  dirent->rec_len);
+		next->inode = 0;
+		next->name_len = 0;
+		next->rec_len = rec_len;
+		return DIRENT_CHANGED;
+	}
+
+	/*
+	 * If we get this far, then the directory entry is not used.
+	 * See if we can fit the request entry in.  If so, do it.
+	 */
+	if (dirent->rec_len < rec_len)
+		return ret;
+	dirent->inode = ls->inode;
+	dirent->name_len = ls->namelen;
+	strncpy(dirent->name, ls->name, ls->namelen);
+	if (ls->sb->s_feature_incompat & EXT2_FEATURE_INCOMPAT_FILETYPE)
+		dirent->name_len |= (ls->flags & 0x7) << 8;
+
+	ls->done++;
+	return DIRENT_ABORT|DIRENT_CHANGED;
+}
+
+/*
+ * Note: the low 3 bits of the flags field are used as the directory
+ * entry filetype.
+ */
+#ifdef __TURBOC__
+ #pragma argsused
+#endif
+errcode_t ext2fs_link(ext2_filsys fs, ext2_ino_t dir, const char *name, 
+		      ext2_ino_t ino, int flags)
+{
+	errcode_t		retval;
+	struct link_struct	ls;
+	struct ext2_inode	inode;
+
+	EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS);
+
+	if (!(fs->flags & EXT2_FLAG_RW))
+		return EXT2_ET_RO_FILSYS;
+
+	ls.name = name;
+	ls.namelen = name ? strlen(name) : 0;
+	ls.inode = ino;
+	ls.flags = flags;
+	ls.done = 0;
+	ls.sb = fs->super;
+
+	retval = ext2fs_dir_iterate(fs, dir, DIRENT_FLAG_INCLUDE_EMPTY,
+				    0, link_proc, &ls);
+	if (retval)
+		return retval;
+
+	if (!ls.done)
+		return EXT2_ET_DIR_NO_SPACE;
+
+	if ((retval = ext2fs_read_inode(fs, dir, &inode)) != 0)
+		return retval;
+
+	if (inode.i_flags & EXT2_INDEX_FL) {
+		inode.i_flags &= ~EXT2_INDEX_FL;
+		if ((retval = ext2fs_write_inode(fs, dir, &inode)) != 0)
+			return retval;
+	}
+
+	return 0;
+}