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-rw-r--r--e2fslib/icount.c482
1 files changed, 0 insertions, 482 deletions
diff --git a/e2fslib/icount.c b/e2fslib/icount.c
deleted file mode 100644
index 1ad3940..0000000
--- a/e2fslib/icount.c
+++ /dev/null
@@ -1,482 +0,0 @@
-/*
- * icount.c --- an efficient inode count abstraction
- *
- * Copyright (C) 1997 Theodore Ts'o.
- *
- * %Begin-Header%
- * This file may be redistributed under the terms of the GNU Public
- * License.
- * %End-Header%
- */
-
-#if HAVE_UNISTD_H
-#include <unistd.h>
-#endif
-#include <string.h>
-#include <stdio.h>
-
-#include "ext2_fs.h"
-#include "ext2fs.h"
-
-/*
- * The data storage strategy used by icount relies on the observation
- * that most inode counts are either zero (for non-allocated inodes),
- * one (for most files), and only a few that are two or more
- * (directories and files that are linked to more than one directory).
- *
- * Also, e2fsck tends to load the icount data sequentially.
- *
- * So, we use an inode bitmap to indicate which inodes have a count of
- * one, and then use a sorted list to store the counts for inodes
- * which are greater than one.
- *
- * We also use an optional bitmap to indicate which inodes are already
- * in the sorted list, to speed up the use of this abstraction by
- * e2fsck's pass 2. Pass 2 increments inode counts as it finds them,
- * so this extra bitmap avoids searching the sorted list to see if a
- * particular inode is on the sorted list already.
- */
-
-struct ext2_icount_el {
- ext2_ino_t ino;
- __u16 count;
-};
-
-struct ext2_icount {
- errcode_t magic;
- ext2fs_inode_bitmap single;
- ext2fs_inode_bitmap multiple;
- ext2_ino_t count;
- ext2_ino_t size;
- ext2_ino_t num_inodes;
- int cursor;
- struct ext2_icount_el *list;
-};
-
-void ext2fs_free_icount(ext2_icount_t icount)
-{
- if (!icount)
- return;
-
- icount->magic = 0;
- if (icount->list)
- ext2fs_free_mem((void **) &icount->list);
- if (icount->single)
- ext2fs_free_inode_bitmap(icount->single);
- if (icount->multiple)
- ext2fs_free_inode_bitmap(icount->multiple);
- ext2fs_free_mem((void **) &icount);
-}
-
-errcode_t ext2fs_create_icount2(ext2_filsys fs, int flags, int size,
- ext2_icount_t hint, ext2_icount_t *ret)
-{
- ext2_icount_t icount;
- errcode_t retval;
- size_t bytes;
- int i;
-
- if (hint) {
- EXT2_CHECK_MAGIC(hint, EXT2_ET_MAGIC_ICOUNT);
- if (hint->size > size)
- size = (size_t) hint->size;
- }
-
- retval = ext2fs_get_mem(sizeof(struct ext2_icount), (void **) &icount);
- if (retval)
- return retval;
- memset(icount, 0, sizeof(struct ext2_icount));
-
- retval = ext2fs_allocate_inode_bitmap(fs, 0,
- &icount->single);
- if (retval)
- goto errout;
-
- if (flags & EXT2_ICOUNT_OPT_INCREMENT) {
- retval = ext2fs_allocate_inode_bitmap(fs, 0,
- &icount->multiple);
- if (retval)
- goto errout;
- } else
- icount->multiple = 0;
-
- if (size) {
- icount->size = size;
- } else {
- /*
- * Figure out how many special case inode counts we will
- * have. We know we will need one for each directory;
- * we also need to reserve some extra room for file links
- */
- retval = ext2fs_get_num_dirs(fs, &icount->size);
- if (retval)
- goto errout;
- icount->size += fs->super->s_inodes_count / 50;
- }
-
- bytes = (size_t) (icount->size * sizeof(struct ext2_icount_el));
-#if 0
- printf("Icount allocated %d entries, %d bytes.\n",
- icount->size, bytes);
-#endif
- retval = ext2fs_get_mem(bytes, (void **) &icount->list);
- if (retval)
- goto errout;
- memset(icount->list, 0, bytes);
-
- icount->magic = EXT2_ET_MAGIC_ICOUNT;
- icount->count = 0;
- icount->cursor = 0;
- icount->num_inodes = fs->super->s_inodes_count;
-
- /*
- * Populate the sorted list with those entries which were
- * found in the hint icount (since those are ones which will
- * likely need to be in the sorted list this time around).
- */
- if (hint) {
- for (i=0; i < hint->count; i++)
- icount->list[i].ino = hint->list[i].ino;
- icount->count = hint->count;
- }
-
- *ret = icount;
- return 0;
-
-errout:
- ext2fs_free_icount(icount);
- return(retval);
-}
-
-errcode_t ext2fs_create_icount(ext2_filsys fs, int flags, int size,
- ext2_icount_t *ret)
-{
- return ext2fs_create_icount2(fs, flags, size, 0, ret);
-}
-
-/*
- * insert_icount_el() --- Insert a new entry into the sorted list at a
- * specified position.
- */
-static struct ext2_icount_el *insert_icount_el(ext2_icount_t icount,
- ext2_ino_t ino, int pos)
-{
- struct ext2_icount_el *el;
- errcode_t retval;
- ext2_ino_t new_size = 0;
- int num;
-
- if (icount->count >= icount->size) {
- if (icount->count) {
- new_size = icount->list[(unsigned)icount->count-1].ino;
- new_size = (ext2_ino_t) (icount->count *
- ((float) icount->num_inodes / new_size));
- }
- if (new_size < (icount->size + 100))
- new_size = icount->size + 100;
-#if 0
- printf("Reallocating icount %d entries...\n", new_size);
-#endif
- retval = ext2fs_resize_mem((size_t) icount->size *
- sizeof(struct ext2_icount_el),
- (size_t) new_size *
- sizeof(struct ext2_icount_el),
- (void **) &icount->list);
- if (retval)
- return 0;
- icount->size = new_size;
- }
- num = (int) icount->count - pos;
- if (num < 0)
- return 0; /* should never happen */
- if (num) {
- memmove(&icount->list[pos+1], &icount->list[pos],
- sizeof(struct ext2_icount_el) * num);
- }
- icount->count++;
- el = &icount->list[pos];
- el->count = 0;
- el->ino = ino;
- return el;
-}
-
-/*
- * get_icount_el() --- given an inode number, try to find icount
- * information in the sorted list. If the create flag is set,
- * and we can't find an entry, create one in the sorted list.
- */
-static struct ext2_icount_el *get_icount_el(ext2_icount_t icount,
- ext2_ino_t ino, int create)
-{
- float range;
- int low, high, mid;
- ext2_ino_t lowval, highval;
-
- if (!icount || !icount->list)
- return 0;
-
- if (create && ((icount->count == 0) ||
- (ino > icount->list[(unsigned)icount->count-1].ino))) {
- return insert_icount_el(icount, ino, (unsigned) icount->count);
- }
- if (icount->count == 0)
- return 0;
-
- if (icount->cursor >= icount->count)
- icount->cursor = 0;
- if (ino == icount->list[icount->cursor].ino)
- return &icount->list[icount->cursor++];
-#if 0
- printf("Non-cursor get_icount_el: %u\n", ino);
-#endif
- low = 0;
- high = (int) icount->count-1;
- while (low <= high) {
-#if 0
- mid = (low+high)/2;
-#else
- if (low == high)
- mid = low;
- else {
- /* Interpolate for efficiency */
- lowval = icount->list[low].ino;
- highval = icount->list[high].ino;
-
- if (ino < lowval)
- range = 0;
- else if (ino > highval)
- range = 1;
- else
- range = ((float) (ino - lowval)) /
- (highval - lowval);
- mid = low + ((int) (range * (high-low)));
- }
-#endif
- if (ino == icount->list[mid].ino) {
- icount->cursor = mid+1;
- return &icount->list[mid];
- }
- if (ino < icount->list[mid].ino)
- high = mid-1;
- else
- low = mid+1;
- }
- /*
- * If we need to create a new entry, it should be right at
- * low (where high will be left at low-1).
- */
- if (create)
- return insert_icount_el(icount, ino, low);
- return 0;
-}
-
-errcode_t ext2fs_icount_validate(ext2_icount_t icount, FILE *out)
-{
- errcode_t ret = 0;
- int i;
- const char *bad = "bad icount";
-
- EXT2_CHECK_MAGIC(icount, EXT2_ET_MAGIC_ICOUNT);
-
- if (icount->count > icount->size) {
- fprintf(out, "%s: count > size\n", bad);
- return EXT2_ET_INVALID_ARGUMENT;
- }
- for (i=1; i < icount->count; i++) {
- if (icount->list[i-1].ino >= icount->list[i].ino) {
- fprintf(out, "%s: list[%d].ino=%u, list[%d].ino=%u\n",
- bad, i-1, icount->list[i-1].ino,
- i, icount->list[i].ino);
- ret = EXT2_ET_INVALID_ARGUMENT;
- }
- }
- return ret;
-}
-
-errcode_t ext2fs_icount_fetch(ext2_icount_t icount, ext2_ino_t ino, __u16 *ret)
-{
- struct ext2_icount_el *el;
-
- EXT2_CHECK_MAGIC(icount, EXT2_ET_MAGIC_ICOUNT);
-
- if (!ino || (ino > icount->num_inodes))
- return EXT2_ET_INVALID_ARGUMENT;
-
- if (ext2fs_test_inode_bitmap(icount->single, ino)) {
- *ret = 1;
- return 0;
- }
- if (icount->multiple &&
- !ext2fs_test_inode_bitmap(icount->multiple, ino)) {
- *ret = 0;
- return 0;
- }
- el = get_icount_el(icount, ino, 0);
- if (!el) {
- *ret = 0;
- return 0;
- }
- *ret = el->count;
- return 0;
-}
-
-errcode_t ext2fs_icount_increment(ext2_icount_t icount, ext2_ino_t ino,
- __u16 *ret)
-{
- struct ext2_icount_el *el;
-
- EXT2_CHECK_MAGIC(icount, EXT2_ET_MAGIC_ICOUNT);
-
- if (!ino || (ino > icount->num_inodes))
- return EXT2_ET_INVALID_ARGUMENT;
-
- if (ext2fs_test_inode_bitmap(icount->single, ino)) {
- /*
- * If the existing count is 1, then we know there is
- * no entry in the list.
- */
- el = get_icount_el(icount, ino, 1);
- if (!el)
- return EXT2_ET_NO_MEMORY;
- ext2fs_unmark_inode_bitmap(icount->single, ino);
- el->count = 2;
- } else if (icount->multiple) {
- /*
- * The count is either zero or greater than 1; if the
- * inode is set in icount->multiple, then there should
- * be an entry in the list, so find it using
- * get_icount_el().
- */
- if (ext2fs_test_inode_bitmap(icount->multiple, ino)) {
- el = get_icount_el(icount, ino, 1);
- if (!el)
- return EXT2_ET_NO_MEMORY;
- el->count++;
- } else {
- /*
- * The count was zero; mark the single bitmap
- * and return.
- */
- zero_count:
- ext2fs_mark_inode_bitmap(icount->single, ino);
- if (ret)
- *ret = 1;
- return 0;
- }
- } else {
- /*
- * The count is either zero or greater than 1; try to
- * find an entry in the list to determine which.
- */
- el = get_icount_el(icount, ino, 0);
- if (!el) {
- /* No entry means the count was zero */
- goto zero_count;
- }
- el = get_icount_el(icount, ino, 1);
- if (!el)
- return EXT2_ET_NO_MEMORY;
- el->count++;
- }
- if (icount->multiple)
- ext2fs_mark_inode_bitmap(icount->multiple, ino);
- if (ret)
- *ret = el->count;
- return 0;
-}
-
-errcode_t ext2fs_icount_decrement(ext2_icount_t icount, ext2_ino_t ino,
- __u16 *ret)
-{
- struct ext2_icount_el *el;
-
- if (!ino || (ino > icount->num_inodes))
- return EXT2_ET_INVALID_ARGUMENT;
-
- EXT2_CHECK_MAGIC(icount, EXT2_ET_MAGIC_ICOUNT);
-
- if (ext2fs_test_inode_bitmap(icount->single, ino)) {
- ext2fs_unmark_inode_bitmap(icount->single, ino);
- if (icount->multiple)
- ext2fs_unmark_inode_bitmap(icount->multiple, ino);
- else {
- el = get_icount_el(icount, ino, 0);
- if (el)
- el->count = 0;
- }
- if (ret)
- *ret = 0;
- return 0;
- }
-
- if (icount->multiple &&
- !ext2fs_test_inode_bitmap(icount->multiple, ino))
- return EXT2_ET_INVALID_ARGUMENT;
-
- el = get_icount_el(icount, ino, 0);
- if (!el || el->count == 0)
- return EXT2_ET_INVALID_ARGUMENT;
-
- el->count--;
- if (el->count == 1)
- ext2fs_mark_inode_bitmap(icount->single, ino);
- if ((el->count == 0) && icount->multiple)
- ext2fs_unmark_inode_bitmap(icount->multiple, ino);
-
- if (ret)
- *ret = el->count;
- return 0;
-}
-
-errcode_t ext2fs_icount_store(ext2_icount_t icount, ext2_ino_t ino,
- __u16 count)
-{
- struct ext2_icount_el *el;
-
- if (!ino || (ino > icount->num_inodes))
- return EXT2_ET_INVALID_ARGUMENT;
-
- EXT2_CHECK_MAGIC(icount, EXT2_ET_MAGIC_ICOUNT);
-
- if (count == 1) {
- ext2fs_mark_inode_bitmap(icount->single, ino);
- if (icount->multiple)
- ext2fs_unmark_inode_bitmap(icount->multiple, ino);
- return 0;
- }
- if (count == 0) {
- ext2fs_unmark_inode_bitmap(icount->single, ino);
- if (icount->multiple) {
- /*
- * If the icount->multiple bitmap is enabled,
- * we can just clear both bitmaps and we're done
- */
- ext2fs_unmark_inode_bitmap(icount->multiple, ino);
- } else {
- el = get_icount_el(icount, ino, 0);
- if (el)
- el->count = 0;
- }
- return 0;
- }
-
- /*
- * Get the icount element
- */
- el = get_icount_el(icount, ino, 1);
- if (!el)
- return EXT2_ET_NO_MEMORY;
- el->count = count;
- ext2fs_unmark_inode_bitmap(icount->single, ino);
- if (icount->multiple)
- ext2fs_mark_inode_bitmap(icount->multiple, ino);
- return 0;
-}
-
-ext2_ino_t ext2fs_get_icount_size(ext2_icount_t icount)
-{
- if (!icount || icount->magic != EXT2_ET_MAGIC_ICOUNT)
- return 0;
-
- return icount->size;
-}