From c3614986ef4bc6d2fe9c37d16c53a70e3ce03d1d Mon Sep 17 00:00:00 2001
From: Alex Shinn <ashinn@users.noreply.github.com>
Date: Tue, 4 Oct 2011 22:15:58 +0900
Subject: [PATCH] adding string<->utf8 conversions

---
 lib/chibi/io.sld     |  1 +
 lib/chibi/io/io.scm  |  3 +++
 lib/chibi/io/io.stub |  5 +++++
 lib/chibi/io/port.c  | 13 +++++++++++++
 4 files changed, 22 insertions(+)

diff --git a/lib/chibi/io.sld b/lib/chibi/io.sld
index ddd19e45..42322da7 100644
--- a/lib/chibi/io.sld
+++ b/lib/chibi/io.sld
@@ -9,6 +9,7 @@
           make-generated-input-port make-filtered-output-port
           make-filtered-input-port
           open-input-bytevector open-output-bytevector get-output-bytevector
+          string->utf8 utf8->string
           write-u8 read-u8 peek-u8)
   (import (scheme) (chibi ast))
   (include-shared "io/io")
diff --git a/lib/chibi/io/io.scm b/lib/chibi/io/io.scm
index 37806bfc..94b351eb 100644
--- a/lib/chibi/io/io.scm
+++ b/lib/chibi/io/io.scm
@@ -21,6 +21,9 @@
          (c 0 (if (eqv? ch (string-ref str i)) (+ c 1) c)))
         ((>= i end) c))))
 
+(define (utf8->string vec)
+  (string-copy (utf8->string! vec)))
+
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ;; reading and writing
 
diff --git a/lib/chibi/io/io.stub b/lib/chibi/io/io.stub
index 6cea880c..f7cafddd 100644
--- a/lib/chibi/io/io.stub
+++ b/lib/chibi/io/io.stub
@@ -33,6 +33,11 @@
 (define-c sexp (get-output-bytevector "sexp_get_output_bytevector")
   ((value ctx sexp) (value self sexp) sexp))
 
+(define-c sexp (string->utf8 "sexp_string_to_utf8")
+  ((value ctx sexp) (value self sexp) sexp))
+(define-c sexp (utf8->string! "sexp_utf8_to_string_x")
+  ((value ctx sexp) (value self sexp) sexp))
+
 (define-c sexp (write-u8 "sexp_write_u8")
   ((value ctx sexp) (value self sexp) sexp (default (current-output-port) sexp)))
 (define-c sexp (read-u8 "sexp_read_u8")
diff --git a/lib/chibi/io/port.c b/lib/chibi/io/port.c
index fef13f80..99ad6d5d 100644
--- a/lib/chibi/io/port.c
+++ b/lib/chibi/io/port.c
@@ -249,6 +249,19 @@ sexp sexp_get_output_bytevector (sexp ctx, sexp self, sexp port) {
   return res;
 }
 
+sexp sexp_string_to_utf8 (sexp ctx, sexp self, sexp str) {
+  sexp res;
+  sexp_assert_type(ctx, sexp_stringp, SEXP_STRING, str);
+  res = sexp_c_string(ctx, sexp_string_data(str), sexp_string_length(str));
+  return sexp_string_to_bytes(ctx, res);
+}
+
+/* TODO: add validation */
+sexp sexp_utf8_to_string_x (sexp ctx, sexp self, sexp vec) {
+  sexp_assert_type(ctx, sexp_bytesp, SEXP_BYTES, vec);
+  return sexp_bytes_to_string(ctx, vec);
+}
+
 sexp sexp_write_u8 (sexp ctx, sexp self, sexp u8, sexp out) {
   sexp_assert_type(ctx, sexp_fixnump, SEXP_FIXNUM, u8);
   if (sexp_unbox_fixnum(u8) < 0 || sexp_unbox_fixnum(u8) > 255)