busybox/e2fsprogs/ext2fs/irel_ma.c

368 lines
8.6 KiB
C

/* vi: set sw=4 ts=4: */
/*
* irel_ma.c
*
* Copyright (C) 1996, 1997 Theodore Ts'o.
*
* %Begin-Header%
* This file may be redistributed under the terms of the GNU Public
* License.
* %End-Header%
*/
#include <fcntl.h>
#include <stdio.h>
#include <string.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#if HAVE_ERRNO_H
#include <errno.h>
#endif
#include "ext2_fs.h"
#include "ext2fs.h"
#include "irel.h"
static errcode_t ima_put(ext2_irel irel, ext2_ino_t old,
struct ext2_inode_relocate_entry *ent);
static errcode_t ima_get(ext2_irel irel, ext2_ino_t old,
struct ext2_inode_relocate_entry *ent);
static errcode_t ima_get_by_orig(ext2_irel irel, ext2_ino_t orig, ext2_ino_t *old,
struct ext2_inode_relocate_entry *ent);
static errcode_t ima_start_iter(ext2_irel irel);
static errcode_t ima_next(ext2_irel irel, ext2_ino_t *old,
struct ext2_inode_relocate_entry *ent);
static errcode_t ima_add_ref(ext2_irel irel, ext2_ino_t ino,
struct ext2_inode_reference *ref);
static errcode_t ima_start_iter_ref(ext2_irel irel, ext2_ino_t ino);
static errcode_t ima_next_ref(ext2_irel irel, struct ext2_inode_reference *ref);
static errcode_t ima_move(ext2_irel irel, ext2_ino_t old, ext2_ino_t new);
static errcode_t ima_delete(ext2_irel irel, ext2_ino_t old);
static errcode_t ima_free(ext2_irel irel);
/*
* This data structure stores the array of inode references; there is
* a structure for each inode.
*/
struct inode_reference_entry {
__u16 num;
struct ext2_inode_reference *refs;
};
struct irel_ma {
__u32 magic;
ext2_ino_t max_inode;
ext2_ino_t ref_current;
int ref_iter;
ext2_ino_t *orig_map;
struct ext2_inode_relocate_entry *entries;
struct inode_reference_entry *ref_entries;
};
errcode_t ext2fs_irel_memarray_create(char *name, ext2_ino_t max_inode,
ext2_irel *new_irel)
{
ext2_irel irel = 0;
errcode_t retval;
struct irel_ma *ma = 0;
size_t size;
*new_irel = 0;
/*
* Allocate memory structures
*/
retval = ext2fs_get_mem(sizeof(struct ext2_inode_relocation_table),
&irel);
if (retval)
goto errout;
memset(irel, 0, sizeof(struct ext2_inode_relocation_table));
retval = ext2fs_get_mem(strlen(name)+1, &irel->name);
if (retval)
goto errout;
strcpy(irel->name, name);
retval = ext2fs_get_mem(sizeof(struct irel_ma), &ma);
if (retval)
goto errout;
memset(ma, 0, sizeof(struct irel_ma));
irel->priv_data = ma;
size = (size_t) (sizeof(ext2_ino_t) * (max_inode+1));
retval = ext2fs_get_mem(size, &ma->orig_map);
if (retval)
goto errout;
memset(ma->orig_map, 0, size);
size = (size_t) (sizeof(struct ext2_inode_relocate_entry) *
(max_inode+1));
retval = ext2fs_get_mem(size, &ma->entries);
if (retval)
goto errout;
memset(ma->entries, 0, size);
size = (size_t) (sizeof(struct inode_reference_entry) *
(max_inode+1));
retval = ext2fs_get_mem(size, &ma->ref_entries);
if (retval)
goto errout;
memset(ma->ref_entries, 0, size);
ma->max_inode = max_inode;
/*
* Fill in the irel data structure
*/
irel->put = ima_put;
irel->get = ima_get;
irel->get_by_orig = ima_get_by_orig;
irel->start_iter = ima_start_iter;
irel->next = ima_next;
irel->add_ref = ima_add_ref;
irel->start_iter_ref = ima_start_iter_ref;
irel->next_ref = ima_next_ref;
irel->move = ima_move;
irel->delete = ima_delete;
irel->free = ima_free;
*new_irel = irel;
return 0;
errout:
ima_free(irel);
return retval;
}
static errcode_t ima_put(ext2_irel irel, ext2_ino_t old,
struct ext2_inode_relocate_entry *ent)
{
struct inode_reference_entry *ref_ent;
struct irel_ma *ma;
errcode_t retval;
size_t size, old_size;
ma = irel->priv_data;
if (old > ma->max_inode)
return EXT2_ET_INVALID_ARGUMENT;
/*
* Force the orig field to the correct value; the application
* program shouldn't be messing with this field.
*/
if (ma->entries[(unsigned) old].new == 0)
ent->orig = old;
else
ent->orig = ma->entries[(unsigned) old].orig;
/*
* If max_refs has changed, reallocate the refs array
*/
ref_ent = ma->ref_entries + (unsigned) old;
if (ref_ent->refs && ent->max_refs !=
ma->entries[(unsigned) old].max_refs) {
size = (sizeof(struct ext2_inode_reference) * ent->max_refs);
old_size = (sizeof(struct ext2_inode_reference) *
ma->entries[(unsigned) old].max_refs);
retval = ext2fs_resize_mem(old_size, size, &ref_ent->refs);
if (retval)
return retval;
}
ma->entries[(unsigned) old] = *ent;
ma->orig_map[(unsigned) ent->orig] = old;
return 0;
}
static errcode_t ima_get(ext2_irel irel, ext2_ino_t old,
struct ext2_inode_relocate_entry *ent)
{
struct irel_ma *ma;
ma = irel->priv_data;
if (old > ma->max_inode)
return EXT2_ET_INVALID_ARGUMENT;
if (ma->entries[(unsigned) old].new == 0)
return ENOENT;
*ent = ma->entries[(unsigned) old];
return 0;
}
static errcode_t ima_get_by_orig(ext2_irel irel, ext2_ino_t orig, ext2_ino_t *old,
struct ext2_inode_relocate_entry *ent)
{
struct irel_ma *ma;
ext2_ino_t ino;
ma = irel->priv_data;
if (orig > ma->max_inode)
return EXT2_ET_INVALID_ARGUMENT;
ino = ma->orig_map[(unsigned) orig];
if (ino == 0)
return ENOENT;
*old = ino;
*ent = ma->entries[(unsigned) ino];
return 0;
}
static errcode_t ima_start_iter(ext2_irel irel)
{
irel->current = 0;
return 0;
}
static errcode_t ima_next(ext2_irel irel, ext2_ino_t *old,
struct ext2_inode_relocate_entry *ent)
{
struct irel_ma *ma;
ma = irel->priv_data;
while (++irel->current < ma->max_inode) {
if (ma->entries[(unsigned) irel->current].new == 0)
continue;
*old = irel->current;
*ent = ma->entries[(unsigned) irel->current];
return 0;
}
*old = 0;
return 0;
}
static errcode_t ima_add_ref(ext2_irel irel, ext2_ino_t ino,
struct ext2_inode_reference *ref)
{
struct irel_ma *ma;
size_t size;
struct inode_reference_entry *ref_ent;
struct ext2_inode_relocate_entry *ent;
errcode_t retval;
ma = irel->priv_data;
if (ino > ma->max_inode)
return EXT2_ET_INVALID_ARGUMENT;
ref_ent = ma->ref_entries + (unsigned) ino;
ent = ma->entries + (unsigned) ino;
/*
* If the inode reference array doesn't exist, create it.
*/
if (ref_ent->refs == 0) {
size = (size_t) ((sizeof(struct ext2_inode_reference) *
ent->max_refs));
retval = ext2fs_get_mem(size, &ref_ent->refs);
if (retval)
return retval;
memset(ref_ent->refs, 0, size);
ref_ent->num = 0;
}
if (ref_ent->num >= ent->max_refs)
return EXT2_ET_TOO_MANY_REFS;
ref_ent->refs[(unsigned) ref_ent->num++] = *ref;
return 0;
}
static errcode_t ima_start_iter_ref(ext2_irel irel, ext2_ino_t ino)
{
struct irel_ma *ma;
ma = irel->priv_data;
if (ino > ma->max_inode)
return EXT2_ET_INVALID_ARGUMENT;
if (ma->entries[(unsigned) ino].new == 0)
return ENOENT;
ma->ref_current = ino;
ma->ref_iter = 0;
return 0;
}
static errcode_t ima_next_ref(ext2_irel irel,
struct ext2_inode_reference *ref)
{
struct irel_ma *ma;
struct inode_reference_entry *ref_ent;
ma = irel->priv_data;
ref_ent = ma->ref_entries + ma->ref_current;
if ((ref_ent->refs == NULL) ||
(ma->ref_iter >= ref_ent->num)) {
ref->block = 0;
ref->offset = 0;
return 0;
}
*ref = ref_ent->refs[ma->ref_iter++];
return 0;
}
static errcode_t ima_move(ext2_irel irel, ext2_ino_t old, ext2_ino_t new)
{
struct irel_ma *ma;
ma = irel->priv_data;
if ((old > ma->max_inode) || (new > ma->max_inode))
return EXT2_ET_INVALID_ARGUMENT;
if (ma->entries[(unsigned) old].new == 0)
return ENOENT;
ma->entries[(unsigned) new] = ma->entries[(unsigned) old];
ext2fs_free_mem(&ma->ref_entries[(unsigned) new].refs);
ma->ref_entries[(unsigned) new] = ma->ref_entries[(unsigned) old];
ma->entries[(unsigned) old].new = 0;
ma->ref_entries[(unsigned) old].num = 0;
ma->ref_entries[(unsigned) old].refs = 0;
ma->orig_map[ma->entries[new].orig] = new;
return 0;
}
static errcode_t ima_delete(ext2_irel irel, ext2_ino_t old)
{
struct irel_ma *ma;
ma = irel->priv_data;
if (old > ma->max_inode)
return EXT2_ET_INVALID_ARGUMENT;
if (ma->entries[(unsigned) old].new == 0)
return ENOENT;
ma->entries[old].new = 0;
ext2fs_free_mem(&ma->ref_entries[(unsigned) old].refs);
ma->orig_map[ma->entries[(unsigned) old].orig] = 0;
ma->ref_entries[(unsigned) old].num = 0;
ma->ref_entries[(unsigned) old].refs = 0;
return 0;
}
static errcode_t ima_free(ext2_irel irel)
{
struct irel_ma *ma;
ext2_ino_t ino;
if (!irel)
return 0;
ma = irel->priv_data;
if (ma) {
ext2fs_free_mem(&ma->orig_map);
ext2fs_free_mem(&ma->entries);
if (ma->ref_entries) {
for (ino = 0; ino <= ma->max_inode; ino++) {
ext2fs_free_mem(&ma->ref_entries[(unsigned) ino].refs);
}
ext2fs_free_mem(&ma->ref_entries);
}
ext2fs_free_mem(&ma);
}
ext2fs_free_mem(&irel->name);
ext2fs_free_mem(&irel);
return 0;
}