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-rw-r--r--e2fslib/dblist.c254
1 files changed, 254 insertions, 0 deletions
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 <stdio.h>
+#if HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#include <string.h>
+#include <time.h>
+
+#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;
+}