diff options
author | Ralf Baechle <ralf@linux-mips.org> | 1998-03-17 22:05:47 +0000 |
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committer | Ralf Baechle <ralf@linux-mips.org> | 1998-03-17 22:05:47 +0000 |
commit | 27cfca1ec98e91261b1a5355d10a8996464b63af (patch) | |
tree | 8e895a53e372fa682b4c0a585b9377d67ed70d0e /fs/hfs/dir_dbl.c | |
parent | 6a76fb7214c477ccf6582bd79c5b4ccc4f9c41b1 (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.c | 464 |
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); + } +} |