diff options
Diffstat (limited to 'e2fsprogs/old_e2fsprogs/ext2fs/link.c')
-rw-r--r-- | e2fsprogs/old_e2fsprogs/ext2fs/link.c | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/e2fsprogs/old_e2fsprogs/ext2fs/link.c b/e2fsprogs/old_e2fsprogs/ext2fs/link.c new file mode 100644 index 0000000..08b2e96 --- /dev/null +++ b/e2fsprogs/old_e2fsprogs/ext2fs/link.c @@ -0,0 +1,135 @@ +/* vi: set sw=4 ts=4: */ +/* + * 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; +} |