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-rw-r--r--e2fsprogs/e2fsck/ea_refcount.c479
1 files changed, 0 insertions, 479 deletions
diff --git a/e2fsprogs/e2fsck/ea_refcount.c b/e2fsprogs/e2fsck/ea_refcount.c
deleted file mode 100644
index 6420c72..0000000
--- a/e2fsprogs/e2fsck/ea_refcount.c
+++ /dev/null
@@ -1,479 +0,0 @@
-/*
- * ea_refcount.c
- *
- * Copyright (C) 2001 Theodore Ts'o. This file may be
- * redistributed under the terms of the GNU Public License.
- */
-
-#if HAVE_UNISTD_H
-#include <unistd.h>
-#endif
-#include <string.h>
-#include <stdio.h>
-
-#include "e2fsck.h"
-
-/*
- * The strategy we use for keeping track of EA refcounts is as
- * follows. We keep a sorted array of first EA blocks and its
- * reference counts. Once the refcount has dropped to zero, it is
- * removed from the array to save memory space. Once the EA block is
- * checked, its bit is set in the block_ea_map bitmap.
- */
-struct ea_refcount_el {
- blk_t ea_blk;
- int ea_count;
-};
-
-struct ea_refcount {
- blk_t count;
- blk_t size;
- blk_t cursor;
- struct ea_refcount_el *list;
-};
-
-void ea_refcount_free(ext2_refcount_t refcount)
-{
- if (!refcount)
- return;
-
- if (refcount->list)
- ext2fs_free_mem(&refcount->list);
- ext2fs_free_mem(&refcount);
-}
-
-errcode_t ea_refcount_create(int size, ext2_refcount_t *ret)
-{
- ext2_refcount_t refcount;
- errcode_t retval;
- size_t bytes;
-
- retval = ext2fs_get_mem(sizeof(struct ea_refcount), &refcount);
- if (retval)
- return retval;
- memset(refcount, 0, sizeof(struct ea_refcount));
-
- if (!size)
- size = 500;
- refcount->size = size;
- bytes = (size_t) (size * sizeof(struct ea_refcount_el));
-#ifdef DEBUG
- printf("Refcount allocated %d entries, %d bytes.\n",
- refcount->size, bytes);
-#endif
- retval = ext2fs_get_mem(bytes, &refcount->list);
- if (retval)
- goto errout;
- memset(refcount->list, 0, bytes);
-
- refcount->count = 0;
- refcount->cursor = 0;
-
- *ret = refcount;
- return 0;
-
-errout:
- ea_refcount_free(refcount);
- return(retval);
-}
-
-/*
- * collapse_refcount() --- go through the refcount array, and get rid
- * of any count == zero entries
- */
-static void refcount_collapse(ext2_refcount_t refcount)
-{
- unsigned int i, j;
- struct ea_refcount_el *list;
-
- list = refcount->list;
- for (i = 0, j = 0; i < refcount->count; i++) {
- if (list[i].ea_count) {
- if (i != j)
- list[j] = list[i];
- j++;
- }
- }
-#if defined(DEBUG) || defined(TEST_PROGRAM)
- printf("Refcount_collapse: size was %d, now %d\n",
- refcount->count, j);
-#endif
- refcount->count = j;
-}
-
-
-/*
- * insert_refcount_el() --- Insert a new entry into the sorted list at a
- * specified position.
- */
-static struct ea_refcount_el *insert_refcount_el(ext2_refcount_t refcount,
- blk_t blk, int pos)
-{
- struct ea_refcount_el *el;
- errcode_t retval;
- blk_t new_size = 0;
- int num;
-
- if (refcount->count >= refcount->size) {
- new_size = refcount->size + 100;
-#ifdef DEBUG
- printf("Reallocating refcount %d entries...\n", new_size);
-#endif
- retval = ext2fs_resize_mem((size_t) refcount->size *
- sizeof(struct ea_refcount_el),
- (size_t) new_size *
- sizeof(struct ea_refcount_el),
- &refcount->list);
- if (retval)
- return 0;
- refcount->size = new_size;
- }
- num = (int) refcount->count - pos;
- if (num < 0)
- return 0; /* should never happen */
- if (num) {
- memmove(&refcount->list[pos+1], &refcount->list[pos],
- sizeof(struct ea_refcount_el) * num);
- }
- refcount->count++;
- el = &refcount->list[pos];
- el->ea_count = 0;
- el->ea_blk = blk;
- return el;
-}
-
-
-/*
- * get_refcount_el() --- given an block number, try to find refcount
- * 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 ea_refcount_el *get_refcount_el(ext2_refcount_t refcount,
- blk_t blk, int create)
-{
- float range;
- int low, high, mid;
- blk_t lowval, highval;
-
- if (!refcount || !refcount->list)
- return 0;
-retry:
- low = 0;
- high = (int) refcount->count-1;
- if (create && ((refcount->count == 0) ||
- (blk > refcount->list[high].ea_blk))) {
- if (refcount->count >= refcount->size)
- refcount_collapse(refcount);
-
- return insert_refcount_el(refcount, blk,
- (unsigned) refcount->count);
- }
- if (refcount->count == 0)
- return 0;
-
- if (refcount->cursor >= refcount->count)
- refcount->cursor = 0;
- if (blk == refcount->list[refcount->cursor].ea_blk)
- return &refcount->list[refcount->cursor++];
-#ifdef DEBUG
- printf("Non-cursor get_refcount_el: %u\n", blk);
-#endif
- while (low <= high) {
-#if 0
- mid = (low+high)/2;
-#else
- if (low == high)
- mid = low;
- else {
- /* Interpolate for efficiency */
- lowval = refcount->list[low].ea_blk;
- highval = refcount->list[high].ea_blk;
-
- if (blk < lowval)
- range = 0;
- else if (blk > highval)
- range = 1;
- else
- range = ((float) (blk - lowval)) /
- (highval - lowval);
- mid = low + ((int) (range * (high-low)));
- }
-#endif
- if (blk == refcount->list[mid].ea_blk) {
- refcount->cursor = mid+1;
- return &refcount->list[mid];
- }
- if (blk < refcount->list[mid].ea_blk)
- 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) {
- if (refcount->count >= refcount->size) {
- refcount_collapse(refcount);
- if (refcount->count < refcount->size)
- goto retry;
- }
- return insert_refcount_el(refcount, blk, low);
- }
- return 0;
-}
-
-errcode_t ea_refcount_fetch(ext2_refcount_t refcount, blk_t blk,
- int *ret)
-{
- struct ea_refcount_el *el;
-
- el = get_refcount_el(refcount, blk, 0);
- if (!el) {
- *ret = 0;
- return 0;
- }
- *ret = el->ea_count;
- return 0;
-}
-
-errcode_t ea_refcount_increment(ext2_refcount_t refcount, blk_t blk, int *ret)
-{
- struct ea_refcount_el *el;
-
- el = get_refcount_el(refcount, blk, 1);
- if (!el)
- return EXT2_ET_NO_MEMORY;
- el->ea_count++;
-
- if (ret)
- *ret = el->ea_count;
- return 0;
-}
-
-errcode_t ea_refcount_decrement(ext2_refcount_t refcount, blk_t blk, int *ret)
-{
- struct ea_refcount_el *el;
-
- el = get_refcount_el(refcount, blk, 0);
- if (!el || el->ea_count == 0)
- return EXT2_ET_INVALID_ARGUMENT;
-
- el->ea_count--;
-
- if (ret)
- *ret = el->ea_count;
- return 0;
-}
-
-errcode_t ea_refcount_store(ext2_refcount_t refcount, blk_t blk, int count)
-{
- struct ea_refcount_el *el;
-
- /*
- * Get the refcount element
- */
- el = get_refcount_el(refcount, blk, count ? 1 : 0);
- if (!el)
- return count ? EXT2_ET_NO_MEMORY : 0;
- el->ea_count = count;
- return 0;
-}
-
-blk_t ext2fs_get_refcount_size(ext2_refcount_t refcount)
-{
- if (!refcount)
- return 0;
-
- return refcount->size;
-}
-
-void ea_refcount_intr_begin(ext2_refcount_t refcount)
-{
- refcount->cursor = 0;
-}
-
-
-blk_t ea_refcount_intr_next(ext2_refcount_t refcount,
- int *ret)
-{
- struct ea_refcount_el *list;
-
- while (1) {
- if (refcount->cursor >= refcount->count)
- return 0;
- list = refcount->list;
- if (list[refcount->cursor].ea_count) {
- if (ret)
- *ret = list[refcount->cursor].ea_count;
- return list[refcount->cursor++].ea_blk;
- }
- refcount->cursor++;
- }
-}
-
-
-#ifdef TEST_PROGRAM
-
-errcode_t ea_refcount_validate(ext2_refcount_t refcount, FILE *out)
-{
- errcode_t ret = 0;
- int i;
- const char *bad = "bad refcount";
-
- if (refcount->count > refcount->size) {
- fprintf(out, "%s: count > size\n", bad);
- return EXT2_ET_INVALID_ARGUMENT;
- }
- for (i=1; i < refcount->count; i++) {
- if (refcount->list[i-1].ea_blk >= refcount->list[i].ea_blk) {
- fprintf(out, "%s: list[%d].blk=%u, list[%d].blk=%u\n",
- bad, i-1, refcount->list[i-1].ea_blk,
- i, refcount->list[i].ea_blk);
- ret = EXT2_ET_INVALID_ARGUMENT;
- }
- }
- return ret;
-}
-
-#define BCODE_END 0
-#define BCODE_CREATE 1
-#define BCODE_FREE 2
-#define BCODE_STORE 3
-#define BCODE_INCR 4
-#define BCODE_DECR 5
-#define BCODE_FETCH 6
-#define BCODE_VALIDATE 7
-#define BCODE_LIST 8
-#define BCODE_COLLAPSE 9
-
-int bcode_program[] = {
- BCODE_CREATE, 5,
- BCODE_STORE, 3, 3,
- BCODE_STORE, 4, 4,
- BCODE_STORE, 1, 1,
- BCODE_STORE, 8, 8,
- BCODE_STORE, 2, 2,
- BCODE_STORE, 4, 0,
- BCODE_STORE, 2, 0,
- BCODE_STORE, 6, 6,
- BCODE_VALIDATE,
- BCODE_STORE, 4, 4,
- BCODE_STORE, 2, 2,
- BCODE_FETCH, 1,
- BCODE_FETCH, 2,
- BCODE_INCR, 3,
- BCODE_INCR, 3,
- BCODE_DECR, 4,
- BCODE_STORE, 4, 4,
- BCODE_VALIDATE,
- BCODE_STORE, 20, 20,
- BCODE_STORE, 40, 40,
- BCODE_STORE, 30, 30,
- BCODE_STORE, 10, 10,
- BCODE_DECR, 30,
- BCODE_FETCH, 30,
- BCODE_DECR, 2,
- BCODE_DECR, 2,
- BCODE_COLLAPSE,
- BCODE_LIST,
- BCODE_VALIDATE,
- BCODE_FREE,
- BCODE_END
-};
-
-int main(int argc, char **argv)
-{
- int i = 0;
- ext2_refcount_t refcount;
- int size, arg;
- blk_t blk;
- errcode_t retval;
-
- while (1) {
- switch (bcode_program[i++]) {
- case BCODE_END:
- exit(0);
- case BCODE_CREATE:
- size = bcode_program[i++];
- retval = ea_refcount_create(size, &refcount);
- if (retval) {
- com_err("ea_refcount_create",
- retval, "");
- exit(1);
- } else
- printf("Creating refcount with size %d\n",
- size);
- break;
- case BCODE_FREE:
- ea_refcount_free(refcount);
- refcount = 0;
- printf("Freeing refcount\n");
- break;
- case BCODE_STORE:
- blk = (blk_t) bcode_program[i++];
- arg = bcode_program[i++];
- retval = ea_refcount_store(refcount, blk, arg);
- printf("Storing blk %u with value %d\n", blk, arg);
- if (retval)
- com_err("ea_refcount_store", retval, "");
- break;
- case BCODE_FETCH:
- blk = (blk_t) bcode_program[i++];
- retval = ea_refcount_fetch(refcount, blk, &arg);
- if (retval)
- com_err("ea_refcount_fetch", retval, "");
- else
- printf("bcode_fetch(%u) returns %d\n",
- blk, arg);
- break;
- case BCODE_INCR:
- blk = (blk_t) bcode_program[i++];
- retval = ea_refcount_increment(refcount, blk,
- &arg);
- if (retval)
- com_err("ea_refcount_increment", retval,
- "");
- else
- printf("bcode_increment(%u) returns %d\n",
- blk, arg);
- break;
- case BCODE_DECR:
- blk = (blk_t) bcode_program[i++];
- retval = ea_refcount_decrement(refcount, blk,
- &arg);
- if (retval)
- com_err("ea_refcount_decrement", retval,
- "while decrementing blk %u", blk);
- else
- printf("bcode_decrement(%u) returns %d\n",
- blk, arg);
- break;
- case BCODE_VALIDATE:
- retval = ea_refcount_validate(refcount, stderr);
- if (retval)
- com_err("ea_refcount_validate",
- retval, "");
- else
- printf("Refcount validation OK.\n");
- break;
- case BCODE_LIST:
- ea_refcount_intr_begin(refcount);
- while (1) {
- blk = ea_refcount_intr_next(refcount,
- &arg);
- if (!blk)
- break;
- printf("\tblk=%u, count=%d\n", blk,
- arg);
- }
- break;
- case BCODE_COLLAPSE:
- refcount_collapse(refcount);
- break;
- }
-
- }
-}
-
-#endif