busybox/e2fsprogs/e2fsck/dx_dirinfo.c
2005-09-24 07:11:16 +00:00

151 lines
3.7 KiB
C

/*
* dirinfo.c --- maintains the directory information table for e2fsck.
*
* Copyright (C) 1993 Theodore Ts'o. This file may be redistributed
* under the terms of the GNU Public License.
*/
#include "e2fsck.h"
#ifdef ENABLE_HTREE
/*
* This subroutine is called during pass1 to create a directory info
* entry. During pass1, the passed-in parent is 0; it will get filled
* in during pass2.
*/
void e2fsck_add_dx_dir(e2fsck_t ctx, ext2_ino_t ino, int num_blocks)
{
struct dx_dir_info *dir;
int i, j;
errcode_t retval;
unsigned long old_size;
#if 0
printf("add_dx_dir_info for inode %lu...\n", ino);
#endif
if (!ctx->dx_dir_info) {
ctx->dx_dir_info_count = 0;
ctx->dx_dir_info_size = 100; /* Guess */
ctx->dx_dir_info = (struct dx_dir_info *)
e2fsck_allocate_memory(ctx, ctx->dx_dir_info_size
* sizeof (struct dx_dir_info),
"directory map");
}
if (ctx->dx_dir_info_count >= ctx->dx_dir_info_size) {
old_size = ctx->dx_dir_info_size * sizeof(struct dx_dir_info);
ctx->dx_dir_info_size += 10;
retval = ext2fs_resize_mem(old_size, ctx->dx_dir_info_size *
sizeof(struct dx_dir_info),
&ctx->dx_dir_info);
if (retval) {
ctx->dx_dir_info_size -= 10;
return;
}
}
/*
* Normally, add_dx_dir_info is called with each inode in
* sequential order; but once in a while (like when pass 3
* needs to recreate the root directory or lost+found
* directory) it is called out of order. In those cases, we
* need to move the dx_dir_info entries down to make room, since
* the dx_dir_info array needs to be sorted by inode number for
* get_dx_dir_info()'s sake.
*/
if (ctx->dx_dir_info_count &&
ctx->dx_dir_info[ctx->dx_dir_info_count-1].ino >= ino) {
for (i = ctx->dx_dir_info_count-1; i > 0; i--)
if (ctx->dx_dir_info[i-1].ino < ino)
break;
dir = &ctx->dx_dir_info[i];
if (dir->ino != ino)
for (j = ctx->dx_dir_info_count++; j > i; j--)
ctx->dx_dir_info[j] = ctx->dx_dir_info[j-1];
} else
dir = &ctx->dx_dir_info[ctx->dx_dir_info_count++];
dir->ino = ino;
dir->numblocks = num_blocks;
dir->hashversion = 0;
dir->dx_block = e2fsck_allocate_memory(ctx, num_blocks
* sizeof (struct dx_dirblock_info),
"dx_block info array");
}
/*
* get_dx_dir_info() --- given an inode number, try to find the directory
* information entry for it.
*/
struct dx_dir_info *e2fsck_get_dx_dir_info(e2fsck_t ctx, ext2_ino_t ino)
{
int low, high, mid;
low = 0;
high = ctx->dx_dir_info_count-1;
if (!ctx->dx_dir_info)
return 0;
if (ino == ctx->dx_dir_info[low].ino)
return &ctx->dx_dir_info[low];
if (ino == ctx->dx_dir_info[high].ino)
return &ctx->dx_dir_info[high];
while (low < high) {
mid = (low+high)/2;
if (mid == low || mid == high)
break;
if (ino == ctx->dx_dir_info[mid].ino)
return &ctx->dx_dir_info[mid];
if (ino < ctx->dx_dir_info[mid].ino)
high = mid;
else
low = mid;
}
return 0;
}
/*
* Free the dx_dir_info structure when it isn't needed any more.
*/
void e2fsck_free_dx_dir_info(e2fsck_t ctx)
{
int i;
struct dx_dir_info *dir;
if (ctx->dx_dir_info) {
dir = ctx->dx_dir_info;
for (i=0; i < ctx->dx_dir_info_count; i++) {
if (dir->dx_block) {
ext2fs_free_mem(&dir->dx_block);
dir->dx_block = 0;
}
}
ext2fs_free_mem(&ctx->dx_dir_info);
ctx->dx_dir_info = 0;
}
ctx->dx_dir_info_size = 0;
ctx->dx_dir_info_count = 0;
}
/*
* Return the count of number of directories in the dx_dir_info structure
*/
int e2fsck_get_num_dx_dirinfo(e2fsck_t ctx)
{
return ctx->dx_dir_info_count;
}
/*
* A simple interator function
*/
struct dx_dir_info *e2fsck_dx_dir_info_iter(e2fsck_t ctx, int *control)
{
if (*control >= ctx->dx_dir_info_count)
return 0;
return(ctx->dx_dir_info + (*control)++);
}
#endif /* ENABLE_HTREE */