From d1e063beb43e595680c65e3804d1f8ddff53373b Mon Sep 17 00:00:00 2001 From: Guido Guenther Date: Sat, 18 Nov 2006 23:48:07 +0100 Subject: Imported Debian version 0.3.8.8 --- e2fslib/dblist.c | 254 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 254 insertions(+) create mode 100644 e2fslib/dblist.c (limited to 'e2fslib/dblist.c') diff --git a/e2fslib/dblist.c b/e2fslib/dblist.c new file mode 100644 index 0000000..a195b5b --- /dev/null +++ b/e2fslib/dblist.c @@ -0,0 +1,254 @@ +/* + * dblist.c -- directory block list functions + * + * Copyright 1997 by Theodore Ts'o + * + * %Begin-Header% + * This file may be redistributed under the terms of the GNU Public + * License. + * %End-Header% + * + */ + +#include +#if HAVE_UNISTD_H +#include +#endif +#include +#include + +#include "ext2_fs.h" +#include "ext2fsP.h" + +static EXT2_QSORT_TYPE dir_block_cmp(const void *a, const void *b); + +/* + * Returns the number of directories in the filesystem as reported by + * the group descriptors. Of course, the group descriptors could be + * wrong! + */ +errcode_t ext2fs_get_num_dirs(ext2_filsys fs, ext2_ino_t *ret_num_dirs) +{ + dgrp_t i; + ext2_ino_t num_dirs, max_dirs; + + EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); + + num_dirs = 0; + max_dirs = fs->super->s_inodes_per_group; + for (i = 0; i < fs->group_desc_count; i++) { + if (fs->group_desc[i].bg_used_dirs_count > max_dirs) + num_dirs += max_dirs / 8; + else + num_dirs += fs->group_desc[i].bg_used_dirs_count; + } + if (num_dirs > fs->super->s_inodes_count) + num_dirs = fs->super->s_inodes_count; + + *ret_num_dirs = num_dirs; + + return 0; +} + +/* + * helper function for making a new directory block list (for + * initialize and copy). + */ +static errcode_t make_dblist(ext2_filsys fs, ext2_ino_t size, ext2_ino_t count, + struct ext2_db_entry *list, + ext2_dblist *ret_dblist) +{ + ext2_dblist dblist; + errcode_t retval; + size_t len; + + EXT2_CHECK_MAGIC(fs, EXT2_ET_MAGIC_EXT2FS_FILSYS); + + if ((ret_dblist == 0) && fs->dblist && + (fs->dblist->magic == EXT2_ET_MAGIC_DBLIST)) + return 0; + + retval = ext2fs_get_mem(sizeof(struct ext2_struct_dblist), + (void **) &dblist); + if (retval) + return retval; + memset(dblist, 0, sizeof(struct ext2_struct_dblist)); + + dblist->magic = EXT2_ET_MAGIC_DBLIST; + dblist->fs = fs; + if (size) + dblist->size = size; + else { + retval = ext2fs_get_num_dirs(fs, &dblist->size); + if (retval) + goto cleanup; + dblist->size = (dblist->size * 2) + 12; + } + len = (size_t) sizeof(struct ext2_db_entry) * dblist->size; + dblist->count = count; + retval = ext2fs_get_mem(len, (void **) &dblist->list); + if (retval) + goto cleanup; + + if (list) + memcpy(dblist->list, list, len); + else + memset(dblist->list, 0, len); + if (ret_dblist) + *ret_dblist = dblist; + else + fs->dblist = dblist; + return 0; +cleanup: + if (dblist) + ext2fs_free_mem((void **) &dblist); + return retval; +} + +/* + * Initialize a directory block list + */ +errcode_t ext2fs_init_dblist(ext2_filsys fs, ext2_dblist *ret_dblist) +{ + ext2_dblist dblist; + errcode_t retval; + + retval = make_dblist(fs, 0, 0, 0, &dblist); + if (retval) + return retval; + + dblist->sorted = 1; + if (ret_dblist) + *ret_dblist = dblist; + else + fs->dblist = dblist; + + return 0; +} + +/* + * Copy a directory block list + */ +errcode_t ext2fs_copy_dblist(ext2_dblist src, ext2_dblist *dest) +{ + ext2_dblist dblist; + errcode_t retval; + + retval = make_dblist(src->fs, src->size, src->count, src->list, + &dblist); + if (retval) + return retval; + dblist->sorted = src->sorted; + *dest = dblist; + return 0; +} + +/* + * Close a directory block list + * + * (moved to closefs.c) + */ + + +/* + * Add a directory block to the directory block list + */ +errcode_t ext2fs_add_dir_block(ext2_dblist dblist, ext2_ino_t ino, blk_t blk, + int blockcnt) +{ + struct ext2_db_entry *new_entry; + errcode_t retval; + unsigned long old_size; + + EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST); + + if (dblist->count >= dblist->size) { + old_size = dblist->size * sizeof(struct ext2_db_entry); + dblist->size += 100; + retval = ext2fs_resize_mem(old_size, (size_t) dblist->size * + sizeof(struct ext2_db_entry), + (void **) &dblist->list); + if (retval) { + dblist->size -= 100; + return retval; + } + } + new_entry = dblist->list + ( (int) dblist->count++); + new_entry->blk = blk; + new_entry->ino = ino; + new_entry->blockcnt = blockcnt; + + dblist->sorted = 0; + + return 0; +} + +/* + * Change the directory block to the directory block list + */ +errcode_t ext2fs_set_dir_block(ext2_dblist dblist, ext2_ino_t ino, blk_t blk, + int blockcnt) +{ + dgrp_t i; + + EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST); + + for (i=0; i < dblist->count; i++) { + if ((dblist->list[i].ino != ino) || + (dblist->list[i].blockcnt != blockcnt)) + continue; + dblist->list[i].blk = blk; + dblist->sorted = 0; + return 0; + } + return EXT2_ET_DB_NOT_FOUND; +} + +/* + * This function iterates over the directory block list + */ +errcode_t ext2fs_dblist_iterate(ext2_dblist dblist, + int (*func)(ext2_filsys fs, + struct ext2_db_entry *db_info, + void *priv_data), + void *priv_data) +{ + ext2_ino_t i; + int ret; + + EXT2_CHECK_MAGIC(dblist, EXT2_ET_MAGIC_DBLIST); + + if (!dblist->sorted) { + qsort(dblist->list, (size_t) dblist->count, + sizeof(struct ext2_db_entry), dir_block_cmp); + dblist->sorted = 1; + } + for (i=0; i < dblist->count; i++) { + ret = (*func)(dblist->fs, &dblist->list[(int)i], priv_data); + if (ret & DBLIST_ABORT) + return 0; + } + return 0; +} + + +static EXT2_QSORT_TYPE dir_block_cmp(const void *a, const void *b) +{ + const struct ext2_db_entry *db_a = + (const struct ext2_db_entry *) a; + const struct ext2_db_entry *db_b = + (const struct ext2_db_entry *) b; + + if (db_a->blk != db_b->blk) + return (int) (db_a->blk - db_b->blk); + + if (db_a->ino != db_b->ino) + return (int) (db_a->ino - db_b->ino); + + return (int) (db_a->blockcnt - db_b->blockcnt); +} + +int ext2fs_dblist_count(ext2_dblist dblist) +{ + return (int) dblist->count; +} -- cgit v1.2.3