libio: split dir_entry_t from dir_iterator_t, add create helper

Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

1 files changed, 98 insertions, 0 deletions

diff --git a/lib/io/src/dir_entry.c b/lib/io/src/dir_entry.c
new file mode 100644
index 0000000..b7f38f5
--- /dev/null
+++ b/lib/io/src/dir_entry.c
@@ -0,0 +1,98 @@
+/* SPDX-License-Identifier: GPL-3.0-or-later */
+/*
+ * dir_entry.c
+ *
+ * Copyright (C) 2023 David Oberhollenzer <goliath@infraroot.at>
+ */
+#include "io/dir_entry.h"
+#include "compat.h"
+
+#include <stdlib.h>
+#include <string.h>
+
+dir_entry_t *dir_entry_create(const char *name)
+{
+	size_t len, name_len;
+	dir_entry_t *out;
+
+	name_len = strlen(name);
+	if (SZ_ADD_OV(name_len, 1, &name_len))
+		return NULL;
+	if (SZ_ADD_OV(sizeof(*out), name_len, &len))
+		return NULL;
+
+	out = calloc(1, len);
+	if (out == NULL)
+		return NULL;
+
+	memcpy(out->name, name, name_len);
+	return out;
+}
+
+dir_entry_xattr_t *dir_entry_xattr_create(const char *key, const sqfs_u8 *value,
+					  size_t value_len)
+{
+	dir_entry_xattr_t *out;
+	size_t len, key_len;
+
+	/* key_ley = strlen(key) + 1 */
+	key_len = strlen(key);
+	if (SZ_ADD_OV(key_len, 1, &key_len))
+		return NULL;
+
+	/* len = key_len + value_len + 1 + sizeof(*out) */
+	if (SZ_ADD_OV(key_len, value_len, &len))
+		return NULL;
+	if (SZ_ADD_OV(len, 1, &len))
+		return NULL;
+	if (SZ_ADD_OV(len, sizeof(*out), &len))
+		return NULL;
+
+	out = calloc(1, len);
+	if (out != NULL) {
+		out->key = out->data;
+		out->value = (sqfs_u8 *)out->data + key_len;
+		out->value_len = value_len;
+
+		memcpy(out->key, key, key_len);
+		memcpy(out->value, value, value_len);
+	}
+
+	return out;
+}
+
+dir_entry_xattr_t *dir_entry_xattr_list_copy(const dir_entry_xattr_t *list)
+{
+	dir_entry_xattr_t *new, *copy = NULL, *copy_last = NULL;
+	const dir_entry_xattr_t *it;
+
+	for (it = list; it != NULL; it = it->next) {
+		new = dir_entry_xattr_create(it->key, it->value,
+					     it->value_len);
+		if (new == NULL) {
+			dir_entry_xattr_list_free(copy);
+			return NULL;
+		}
+
+		if (copy_last == NULL) {
+			copy = new;
+			copy_last = new;
+		} else {
+			copy_last->next = new;
+			copy_last = new;
+		}
+	}
+
+	return copy;
+}
+
+void dir_entry_xattr_list_free(dir_entry_xattr_t *list)
+{
+	dir_entry_xattr_t *old;
+
+	while (list != NULL) {
+		old = list;
+		list = list->next;
+		free(old);
+	}
+}