@@ -1,3 +1,5 @@
charsets-y += core.o
obj-$(CONFIG_CHARSETS) += charsets.o
+
+obj-$(CONFIG_CHARSETS) += ascii.o
new file mode 100644
@@ -0,0 +1,98 @@
+/*
+ * Copyright (c) 2017 Collabora Ltd.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+#include <linux/types.h>
+#include <linux/module.h>
+#include <linux/charsets.h>
+#include <linux/string.h>
+#include <linux/ctype.h>
+#include <linux/parser.h>
+
+static struct charset_info ascii_info;
+
+int ascii_strncmp(const struct charset *charset, const char *str1,
+ const char *str2, int len)
+{
+ return strncmp(str1, str2, len);
+}
+
+int ascii_strncasecmp(const struct charset *charset, const char *str1,
+ const char *str2, int len)
+{
+ return strncasecmp(str1, str2, len);
+}
+
+int ascii_normalize(const struct charset *charset, const char *str,
+ int len, char **normalization)
+{
+ *normalization = kstrdup(str, GFP_NOFS);
+ return (*normalization) ? len : -ENOMEM;
+}
+
+int ascii_casefold(const struct charset *charset, const char *str,
+ int len, char **folded_str)
+{
+ int i;
+ char *fold;
+
+ fold = kstrdup(str, GFP_NOFS);
+ if (!fold)
+ return -ENOMEM;
+
+ for (i = 0; i < len; i++)
+ fold[i] = tolower(fold[i]);
+
+ *folded_str = fold;
+ return len;
+}
+
+static const struct charset_ops ascii_ops = {
+ .strncmp = ascii_strncmp,
+ .strncasecmp = ascii_strncasecmp,
+ .casefold = ascii_casefold,
+ .normalize = ascii_normalize,
+};
+
+static struct charset ascii_charset = {
+ .version = 0,
+ .info = &ascii_info,
+ .ops = &ascii_ops
+};
+
+static struct charset *ascii_load_charset(void *pargs)
+{
+ return &ascii_charset;
+}
+
+static struct charset_info ascii_info = {
+ .name = "ascii",
+ .match_token = "ascii",
+ .load_charset = ascii_load_charset,
+};
+
+static int __init init_ascii(void)
+{
+ charset_register(&ascii_info);
+ return 0;
+}
+
+static void __exit exit_ascii(void)
+{
+}
+
+module_init(init_ascii);
+module_exit(exit_ascii);
+MODULE_AUTHOR("Gabriel Krisman Bertazi");
+MODULE_DESCRIPTION("ASCII charset for filesystems");
+MODULE_LICENSE("GPL");
+
This allows filesystems to always use the charsets interfaces, even when not caring about encoding. Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.co.uk> --- lib/charsets/Makefile | 2 ++ lib/charsets/ascii.c | 98 +++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 100 insertions(+) create mode 100644 lib/charsets/ascii.c