1 files changed, 60 insertions, 0 deletions
diff --git a/lib/base32.h b/lib/base32.h
new file mode 100644
index 0000000..e45f3a0
--- /dev/null
+++ b/lib/base32.h
@@ -0,0 +1,60 @@
+/* base32.h -- Encode binary data using printable characters.
+   Copyright (C) 2004-2006, 2009-2020 Free Software Foundation, Inc.
+   Adapted from Simon Josefsson's base64 code by Gijs van Tulder.
+
+   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; either version 3, or (at your option)
+   any later version.
+
+   This program is distributed in the hope that it will 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.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, see <https://www.gnu.org/licenses/>.  */
+
+#ifndef BASE32_H
+# define BASE32_H
+
+/* Get size_t. */
+# include <stddef.h>
+
+/* Get bool. */
+# include <stdbool.h>
+
+/* This uses that the expression (n+(k-1))/k means the smallest
+   integer >= n/k, i.e., the ceiling of n/k.  */
+# define BASE32_LENGTH(inlen) ((((inlen) + 4) / 5) * 8)
+
+struct base32_decode_context
+{
+  unsigned int i;
+  char buf[8];
+};
+
+extern bool isbase32 (char ch) _GL_ATTRIBUTE_CONST;
+
+extern void base32_encode (const char *restrict in, size_t inlen,
+                           char *restrict out, size_t outlen);
+
+extern size_t base32_encode_alloc (const char *in, size_t inlen, char **out);
+
+extern void base32_decode_ctx_init (struct base32_decode_context *ctx);
+
+extern bool base32_decode_ctx (struct base32_decode_context *ctx,
+                               const char *restrict in, size_t inlen,
+                               char *restrict out, size_t *outlen);
+
+extern bool base32_decode_alloc_ctx (struct base32_decode_context *ctx,
+                                     const char *in, size_t inlen,
+                                     char **out, size_t *outlen);
+
+#define base32_decode(in, inlen, out, outlen) \
+        base32_decode_ctx (NULL, in, inlen, out, outlen)
+
+#define base32_decode_alloc(in, inlen, out, outlen) \
+        base32_decode_alloc_ctx (NULL, in, inlen, out, outlen)
+
+#endif /* BASE32_H */