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authorRalf Baechle <ralf@linux-mips.org>1998-03-17 22:05:47 +0000
committerRalf Baechle <ralf@linux-mips.org>1998-03-17 22:05:47 +0000
commit27cfca1ec98e91261b1a5355d10a8996464b63af (patch)
tree8e895a53e372fa682b4c0a585b9377d67ed70d0e /fs/hfs/dir_dbl.c
parent6a76fb7214c477ccf6582bd79c5b4ccc4f9c41b1 (diff)
Look Ma' what I found on my harddisk ...
o New faster syscalls for 2.1.x, too o Upgrade to 2.1.89. Don't try to run this. It's flaky as hell. But feel free to debug ...
Diffstat (limited to 'fs/hfs/dir_dbl.c')
-rw-r--r--fs/hfs/dir_dbl.c464
1 files changed, 464 insertions, 0 deletions
diff --git a/fs/hfs/dir_dbl.c b/fs/hfs/dir_dbl.c
new file mode 100644
index 000000000..c97247dc9
--- /dev/null
+++ b/fs/hfs/dir_dbl.c
@@ -0,0 +1,464 @@
+/*
+ * linux/fs/hfs/dir_dbl.c
+ *
+ * Copyright (C) 1995-1997 Paul H. Hargrove
+ * This file may be distributed under the terms of the GNU Public License.
+ *
+ * This file contains the inode_operations and file_operations
+ * structures for HFS directories.
+ *
+ * Based on the minix file system code, (C) 1991, 1992 by Linus Torvalds
+ *
+ * "XXX" in a comment is a note to myself to consider changing something.
+ *
+ * In function preconditions the term "valid" applied to a pointer to
+ * a structure means that the pointer is non-NULL and the structure it
+ * points to has all fields initialized to consistent values.
+ */
+
+#include "hfs.h"
+#include <linux/hfs_fs_sb.h>
+#include <linux/hfs_fs_i.h>
+#include <linux/hfs_fs.h>
+
+/*================ Forward declarations ================*/
+
+static int dbl_lookup(struct inode *, struct dentry *);
+static int dbl_readdir(struct file *, void *, filldir_t);
+static int dbl_create(struct inode *, struct dentry *, int);
+static int dbl_mkdir(struct inode *, struct dentry *, int);
+static int dbl_mknod(struct inode *, struct dentry *, int, int);
+static int dbl_unlink(struct inode *, struct dentry *);
+static int dbl_rmdir(struct inode *, struct dentry *);
+static int dbl_rename(struct inode *, struct dentry *,
+ struct inode *, struct dentry *);
+
+/*================ Global variables ================*/
+
+#define DOT_LEN 1
+#define DOT_DOT_LEN 2
+#define ROOTINFO_LEN 8
+#define PCNT_ROOTINFO_LEN 9
+
+const struct hfs_name hfs_dbl_reserved1[] = {
+ {DOT_LEN, "."},
+ {DOT_DOT_LEN, ".."},
+ {0, ""},
+};
+
+const struct hfs_name hfs_dbl_reserved2[] = {
+ {ROOTINFO_LEN, "RootInfo"},
+ {PCNT_ROOTINFO_LEN, "%RootInfo"},
+ {0, ""},
+};
+
+#define DOT (&hfs_dbl_reserved1[0])
+#define DOT_DOT (&hfs_dbl_reserved1[1])
+#define ROOTINFO (&hfs_dbl_reserved2[0])
+#define PCNT_ROOTINFO (&hfs_dbl_reserved2[1])
+
+static struct file_operations hfs_dbl_dir_operations = {
+ NULL, /* lseek - default */
+ hfs_dir_read, /* read - invalid */
+ NULL, /* write - bad */
+ dbl_readdir, /* readdir */
+ NULL, /* select - default */
+ NULL, /* ioctl - default */
+ NULL, /* mmap - none */
+ NULL, /* no special open code */
+ NULL, /* no special release code */
+ file_fsync, /* fsync - default */
+ NULL, /* fasync - default */
+ NULL, /* check_media_change - none */
+ NULL /* revalidate - none */
+};
+
+struct inode_operations hfs_dbl_dir_inode_operations = {
+ &hfs_dbl_dir_operations,/* default directory file-ops */
+ dbl_create, /* create */
+ dbl_lookup, /* lookup */
+ NULL, /* link */
+ dbl_unlink, /* unlink */
+ NULL, /* symlink */
+ dbl_mkdir, /* mkdir */
+ dbl_rmdir, /* rmdir */
+ dbl_mknod, /* mknod */
+ dbl_rename, /* rename */
+ NULL, /* readlink */
+ NULL, /* follow_link */
+ NULL, /* readpage */
+ NULL, /* writepage */
+ NULL, /* bmap */
+ NULL, /* truncate */
+ NULL, /* permission */
+ NULL /* smap */
+};
+
+
+/*================ File-local functions ================*/
+
+/*
+ * is_hdr()
+ */
+static int is_hdr(struct inode *dir, const char *name, int len)
+{
+ int retval = 0;
+
+ if (name[0] == '%') {
+ struct hfs_cat_entry *entry = HFS_I(dir)->entry;
+ struct hfs_cat_entry *victim;
+ struct hfs_name cname;
+ struct hfs_cat_key key;
+
+ hfs_nameout(dir, &cname, name+1, len-1);
+ hfs_cat_build_key(entry->cnid, &cname, &key);
+ if ((victim = hfs_cat_get(entry->mdb, &key))) {
+ hfs_cat_put(victim);
+ retval = 1;
+ }
+ }
+ return retval;
+}
+
+/*
+ * dbl_lookup()
+ *
+ * This is the lookup() entry in the inode_operations structure for
+ * HFS directories in the AppleDouble scheme. The purpose is to
+ * generate the inode corresponding to an entry in a directory, given
+ * the inode for the directory and the name (and its length) of the
+ * entry.
+ */
+static int dbl_lookup(struct inode * dir, struct dentry *dentry)
+{
+ struct hfs_name cname;
+ struct hfs_cat_entry *entry;
+ struct hfs_cat_key key;
+ struct inode *inode = NULL;
+
+ if (!dir || !S_ISDIR(dir->i_mode)) {
+ goto done;
+ }
+
+ entry = HFS_I(dir)->entry;
+
+ /* Perform name-mangling */
+ hfs_nameout(dir, &cname, dentry->d_name.name, dentry->d_name.len);
+
+ /* Check for "." */
+ if (hfs_streq(&cname, DOT)) {
+ /* this little trick skips the iget and iput */
+ d_add(dentry, dir);
+ return 0;
+ }
+
+ /* Check for "..". */
+ if (hfs_streq(&cname, DOT_DOT)) {
+ inode = hfs_iget(hfs_cat_parent(entry), HFS_DBL_DIR, dentry);
+ goto done;
+ }
+
+ /* Check for "%RootInfo" if in the root directory. */
+ if ((entry->cnid == htonl(HFS_ROOT_CNID)) &&
+ hfs_streq(&cname, PCNT_ROOTINFO)) {
+ ++entry->count; /* __hfs_iget() eats one */
+ inode = hfs_iget(entry, HFS_DBL_HDR, dentry);
+ goto done;
+ }
+
+ /* Do an hfs_iget() on the mangled name. */
+ hfs_cat_build_key(entry->cnid, &cname, &key);
+ inode = hfs_iget(hfs_cat_get(entry->mdb, &key), HFS_DBL_NORM, dentry);
+
+ /* Try as a header if not found and first character is '%' */
+ if (!inode && (dentry->d_name.name[0] == '%')) {
+ hfs_nameout(dir, &cname, dentry->d_name.name+1,
+ dentry->d_name.len-1);
+ hfs_cat_build_key(entry->cnid, &cname, &key);
+ inode = hfs_iget(hfs_cat_get(entry->mdb, &key),
+ HFS_DBL_HDR, dentry);
+ }
+
+done:
+ dentry->d_op = &hfs_dentry_operations;
+ d_add(dentry, inode);
+ return 0;
+}
+
+/*
+ * dbl_readdir()
+ *
+ * This is the readdir() entry in the file_operations structure for
+ * HFS directories in the AppleDouble scheme. The purpose is to
+ * enumerate the entries in a directory, given the inode of the
+ * directory and a (struct file *), the 'f_pos' field of which
+ * indicates the location in the directory. The (struct file *) is
+ * updated so that the next call with the same 'dir' and 'filp'
+ * arguments will produce the next directory entry. The entries are
+ * returned in 'dirent', which is "filled-in" by calling filldir().
+ * This allows the same readdir() function be used for different
+ * formats. We try to read in as many entries as we can before
+ * filldir() refuses to take any more.
+ *
+ * XXX: In the future it may be a good idea to consider not generating
+ * metadata files for covered directories since the data doesn't
+ * correspond to the mounted directory. However this requires an
+ * iget() for every directory which could be considered an excessive
+ * amount of overhead. Since the inode for a mount point is always
+ * in-core this is another argument for a call to get an inode if it
+ * is in-core or NULL if it is not.
+ */
+static int dbl_readdir(struct file * filp,
+ void * dirent, filldir_t filldir)
+{
+ struct hfs_brec brec;
+ struct hfs_cat_entry *entry;
+ struct inode *dir = filp->f_dentry->d_inode;
+
+ if (!dir || !dir->i_sb || !S_ISDIR(dir->i_mode)) {
+ return -EBADF;
+ }
+
+ entry = HFS_I(dir)->entry;
+
+ if (filp->f_pos == 0) {
+ /* Entry 0 is for "." */
+ if (filldir(dirent, DOT->Name, DOT_LEN, 0, dir->i_ino)) {
+ return 0;
+ }
+ filp->f_pos = 1;
+ }
+
+ if (filp->f_pos == 1) {
+ /* Entry 1 is for ".." */
+ if (filldir(dirent, DOT_DOT->Name, DOT_DOT_LEN, 1,
+ hfs_get_hl(entry->key.ParID))) {
+ return 0;
+ }
+ filp->f_pos = 2;
+ }
+
+ if (filp->f_pos < (dir->i_size - 1)) {
+ hfs_u32 cnid;
+ hfs_u8 type;
+
+ if (hfs_cat_open(entry, &brec) ||
+ hfs_cat_next(entry, &brec, (filp->f_pos - 1) >> 1,
+ &cnid, &type)) {
+ return 0;
+ }
+
+ while (filp->f_pos < (dir->i_size - 1)) {
+ unsigned char tmp_name[HFS_NAMEMAX + 1];
+ ino_t ino;
+ int is_hdr = (filp->f_pos & 1);
+ unsigned int len;
+
+ if (is_hdr) {
+ ino = ntohl(cnid) | HFS_DBL_HDR;
+ tmp_name[0] = '%';
+ len = 1 + hfs_namein(dir, tmp_name + 1,
+ &((struct hfs_cat_key *)brec.key)->CName);
+ } else {
+ if (hfs_cat_next(entry, &brec, 1,
+ &cnid, &type)) {
+ return 0;
+ }
+ ino = ntohl(cnid);
+ len = hfs_namein(dir, tmp_name,
+ &((struct hfs_cat_key *)brec.key)->CName);
+ }
+
+ if (filldir(dirent, tmp_name, len, filp->f_pos, ino)) {
+ hfs_cat_close(entry, &brec);
+ return 0;
+ }
+ ++filp->f_pos;
+ }
+ hfs_cat_close(entry, &brec);
+ }
+
+ if (filp->f_pos == (dir->i_size - 1)) {
+ if (entry->cnid == htonl(HFS_ROOT_CNID)) {
+ /* In root dir last entry is for "%RootInfo" */
+ if (filldir(dirent, PCNT_ROOTINFO->Name,
+ PCNT_ROOTINFO_LEN, filp->f_pos,
+ ntohl(entry->cnid) | HFS_DBL_HDR)) {
+ return 0;
+ }
+ }
+ ++filp->f_pos;
+ }
+
+ return 0;
+}
+
+/*
+ * dbl_create()
+ *
+ * This is the create() entry in the inode_operations structure for
+ * AppleDouble directories. The purpose is to create a new file in
+ * a directory and return a corresponding inode, given the inode for
+ * the directory and the name (and its length) of the new file.
+ */
+static int dbl_create(struct inode * dir, struct dentry *dentry,
+ int mode)
+{
+ int error;
+
+ if (is_hdr(dir, dentry->d_name.name, dentry->d_name.len)) {
+ error = -EEXIST;
+ } else {
+ error = hfs_create(dir, dentry, mode);
+ }
+ return error;
+}
+
+/*
+ * dbl_mkdir()
+ *
+ * This is the mkdir() entry in the inode_operations structure for
+ * AppleDouble directories. The purpose is to create a new directory
+ * in a directory, given the inode for the parent directory and the
+ * name (and its length) of the new directory.
+ */
+static int dbl_mkdir(struct inode * parent, struct dentry *dentry,
+ int mode)
+{
+ int error;
+
+ if (is_hdr(parent, dentry->d_name.name, dentry->d_name.len)) {
+ error = -EEXIST;
+ } else {
+ error = hfs_mkdir(parent, dentry, mode);
+ }
+ return error;
+}
+
+/*
+ * dbl_mknod()
+ *
+ * This is the mknod() entry in the inode_operations structure for
+ * regular HFS directories. The purpose is to create a new entry
+ * in a directory, given the inode for the parent directory and the
+ * name (and its length) and the mode of the new entry (and the device
+ * number if the entry is to be a device special file).
+ */
+static int dbl_mknod(struct inode *dir, struct dentry *dentry,
+ int mode, int rdev)
+{
+ int error;
+
+ if (is_hdr(dir, dentry->d_name.name, dentry->d_name.len)) {
+ error = -EEXIST;
+ } else {
+ error = hfs_mknod(dir, dentry, mode, rdev);
+ }
+ return error;
+}
+
+/*
+ * dbl_unlink()
+ *
+ * This is the unlink() entry in the inode_operations structure for
+ * AppleDouble directories. The purpose is to delete an existing
+ * file, given the inode for the parent directory and the name
+ * (and its length) of the existing file.
+ */
+static int dbl_unlink(struct inode * dir, struct dentry *dentry)
+{
+ int error;
+
+ error = hfs_unlink(dir, dentry);
+ if ((error == -ENOENT) && is_hdr(dir, dentry->d_name.name,
+ dentry->d_name.len)) {
+ error = -EPERM;
+ }
+ return error;
+}
+
+/*
+ * dbl_rmdir()
+ *
+ * This is the rmdir() entry in the inode_operations structure for
+ * AppleDouble directories. The purpose is to delete an existing
+ * directory, given the inode for the parent directory and the name
+ * (and its length) of the existing directory.
+ */
+static int dbl_rmdir(struct inode * parent, struct dentry *dentry)
+{
+ int error;
+
+ error = hfs_rmdir(parent, dentry);
+ if ((error == -ENOENT) && is_hdr(parent, dentry->d_name.name,
+ dentry->d_name.len)) {
+ error = -ENOTDIR;
+ }
+ return error;
+}
+
+/*
+ * dbl_rename()
+ *
+ * This is the rename() entry in the inode_operations structure for
+ * AppleDouble directories. The purpose is to rename an existing
+ * file or directory, given the inode for the current directory and
+ * the name (and its length) of the existing file/directory and the
+ * inode for the new directory and the name (and its length) of the
+ * new file/directory.
+ *
+ * XXX: how do we handle must_be_dir?
+ */
+static int dbl_rename(struct inode *old_dir, struct dentry *old_dentry,
+ struct inode *new_dir, struct dentry *new_dentry)
+{
+ int error;
+
+ if (is_hdr(new_dir, new_dentry->d_name.name,
+ new_dentry->d_name.len)) {
+ error = -EPERM;
+ } else {
+ error = hfs_rename(old_dir, old_dentry,
+ new_dir, new_dentry);
+ if ((error == -ENOENT) /*&& !must_be_dir*/ &&
+ is_hdr(old_dir, old_dentry->d_name.name,
+ old_dentry->d_name.len)) {
+ error = -EPERM;
+ }
+ }
+ return error;
+}
+
+
+/* due to the dcache caching negative dentries for non-existent files,
+ * we need to drop those entries when a file silently gets created.
+ * as far as i can tell, the calls that need to do this are the file
+ * related calls (create, rename, and mknod). the directory calls
+ * should be immune. the relevant calls in dir.c call drop_dentry
+ * upon successful completion. this allocates an array for %name
+ * on the first attempt to access it. */
+void hfs_dbl_drop_dentry(const ino_t type, struct dentry *dentry)
+{
+ unsigned char tmp_name[HFS_NAMEMAX + 1];
+ struct dentry *de = NULL;
+
+ switch (type) {
+ case HFS_DBL_HDR:
+ /* given %name, look for name. i don't think this happens. */
+ de = hfs_lookup_dentry(dentry->d_name.name + 1, dentry->d_name.len - 1,
+ dentry->d_parent);
+ break;
+ case HFS_DBL_DATA:
+ /* given name, look for %name */
+ tmp_name[0] = '%';
+ strncpy(tmp_name + 1, dentry->d_name.name, HFS_NAMELEN - 1);
+ de = hfs_lookup_dentry(tmp_name, dentry->d_name.len + 1,
+ dentry->d_parent);
+ }
+
+ if (de) {
+ if (!de->d_inode)
+ d_drop(de);
+ dput(de);
+ }
+}