Use GNU libunistring and Gnulib modules needed by R6RS bytevectors and ports.

[bpt/guile.git] / lib / unistr / u8-mbtouc-aux.c

diff --git a/lib/unistr/u8-mbtouc-aux.c b/lib/unistr/u8-mbtouc-aux.c
new file mode 100644 (file)
index 0000000..53d02bf
--- /dev/null
+++ b/lib/unistr/u8-mbtouc-aux.c
@@ -0,0 +1,158 @@
+/* Conversion UTF-8 to UCS-4.
+   Copyright (C) 2001-2002, 2006-2007, 2009 Free Software Foundation, Inc.
+   Written by Bruno Haible <bruno@clisp.org>, 2001.
+
+   This program is free software: you can redistribute it and/or modify it
+   under the terms of the GNU Lesser General Public License as published
+   by the Free Software Foundation; either version 3 of the License, 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+/* Specification.  */
+#include "unistr.h"
+
+#if defined IN_LIBUNISTRING || HAVE_INLINE
+
+int
+u8_mbtouc_aux (ucs4_t *puc, const uint8_t *s, size_t n)
+{
+  uint8_t c = *s;
+
+  if (c >= 0xc2)
+    {
+      if (c < 0xe0)
+       {
+         if (n >= 2)
+           {
+             if ((s[1] ^ 0x80) < 0x40)
+               {
+                 *puc = ((unsigned int) (c & 0x1f) << 6)
+                        | (unsigned int) (s[1] ^ 0x80);
+                 return 2;
+               }
+             /* invalid multibyte character */
+           }
+         else
+           {
+             /* incomplete multibyte character */
+             *puc = 0xfffd;
+             return n;
+           }
+       }
+      else if (c < 0xf0)
+       {
+         if (n >= 3)
+           {
+             if ((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40
+                 && (c >= 0xe1 || s[1] >= 0xa0)
+                 && (c != 0xed || s[1] < 0xa0))
+               {
+                 *puc = ((unsigned int) (c & 0x0f) << 12)
+                        | ((unsigned int) (s[1] ^ 0x80) << 6)
+                        | (unsigned int) (s[2] ^ 0x80);
+                 return 3;
+               }
+             /* invalid multibyte character */
+           }
+         else
+           {
+             /* incomplete multibyte character */
+             *puc = 0xfffd;
+             return n;
+           }
+       }
+      else if (c < 0xf8)
+       {
+         if (n >= 4)
+           {
+             if ((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40
+                 && (s[3] ^ 0x80) < 0x40
+                 && (c >= 0xf1 || s[1] >= 0x90)
+#if 1
+                 && (c < 0xf4 || (c == 0xf4 && s[1] < 0x90))
+#endif
+                )
+               {
+                 *puc = ((unsigned int) (c & 0x07) << 18)
+                        | ((unsigned int) (s[1] ^ 0x80) << 12)
+                        | ((unsigned int) (s[2] ^ 0x80) << 6)
+                        | (unsigned int) (s[3] ^ 0x80);
+                 return 4;
+               }
+             /* invalid multibyte character */
+           }
+         else
+           {
+             /* incomplete multibyte character */
+             *puc = 0xfffd;
+             return n;
+           }
+       }
+#if 0
+      else if (c < 0xfc)
+       {
+         if (n >= 5)
+           {
+             if ((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40
+                 && (s[3] ^ 0x80) < 0x40 && (s[4] ^ 0x80) < 0x40
+                 && (c >= 0xf9 || s[1] >= 0x88))
+               {
+                 *puc = ((unsigned int) (c & 0x03) << 24)
+                        | ((unsigned int) (s[1] ^ 0x80) << 18)
+                        | ((unsigned int) (s[2] ^ 0x80) << 12)
+                        | ((unsigned int) (s[3] ^ 0x80) << 6)
+                        | (unsigned int) (s[4] ^ 0x80);
+                 return 5;
+               }
+             /* invalid multibyte character */
+           }
+         else
+           {
+             /* incomplete multibyte character */
+             *puc = 0xfffd;
+             return n;
+           }
+       }
+      else if (c < 0xfe)
+       {
+         if (n >= 6)
+           {
+             if ((s[1] ^ 0x80) < 0x40 && (s[2] ^ 0x80) < 0x40
+                 && (s[3] ^ 0x80) < 0x40 && (s[4] ^ 0x80) < 0x40
+                 && (s[5] ^ 0x80) < 0x40
+                 && (c >= 0xfd || s[1] >= 0x84))
+               {
+                 *puc = ((unsigned int) (c & 0x01) << 30)
+                        | ((unsigned int) (s[1] ^ 0x80) << 24)
+                        | ((unsigned int) (s[2] ^ 0x80) << 18)
+                        | ((unsigned int) (s[3] ^ 0x80) << 12)
+                        | ((unsigned int) (s[4] ^ 0x80) << 6)
+                        | (unsigned int) (s[5] ^ 0x80);
+                 return 6;
+               }
+             /* invalid multibyte character */
+           }
+         else
+           {
+             /* incomplete multibyte character */
+             *puc = 0xfffd;
+             return n;
+           }
+       }
+#endif
+    }
+  /* invalid multibyte character */
+  *puc = 0xfffd;
+  return 1;
+}
+
+#endif