--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/harfbuzz/src/hb-utf.hh	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,453 @@
+/*
+ * Copyright © 2011,2012,2014  Google, Inc.
+ *
+ *  This is part of HarfBuzz, a text shaping library.
+ *
+ * Permission is hereby granted, without written agreement and without
+ * license or royalty fees, to use, copy, modify, and distribute this
+ * software and its documentation for any purpose, provided that the
+ * above copyright notice and the following two paragraphs appear in
+ * all copies of this software.
+ *
+ * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
+ * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+ * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
+ * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+ * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
+ * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
+ *
+ * Google Author(s): Behdad Esfahbod
+ */
+
+#ifndef HB_UTF_HH
+#define HB_UTF_HH
+
+#include "hb.hh"
+
+#include "hb-open-type.hh"
+
+
+struct hb_utf8_t
+{
+  typedef uint8_t codepoint_t;
+
+  static const codepoint_t *
+  next (const codepoint_t *text,
+	const codepoint_t *end,
+	hb_codepoint_t *unicode,
+	hb_codepoint_t replacement)
+  {
+    /* Written to only accept well-formed sequences.
+     * Based on ideas from ICU's U8_NEXT.
+     * Generates one "replacement" for each ill-formed byte. */
+
+    hb_codepoint_t c = *text++;
+
+    if (c > 0x7Fu)
+    {
+      if (hb_in_range<hb_codepoint_t> (c, 0xC2u, 0xDFu)) /* Two-byte */
+      {
+	unsigned int t1;
+	if (likely (text < end &&
+		    (t1 = text[0] - 0x80u) <= 0x3Fu))
+	{
+	  c = ((c&0x1Fu)<<6) | t1;
+	  text++;
+	}
+	else
+	  goto error;
+      }
+      else if (hb_in_range<hb_codepoint_t> (c, 0xE0u, 0xEFu)) /* Three-byte */
+      {
+	unsigned int t1, t2;
+	if (likely (1 < end - text &&
+		    (t1 = text[0] - 0x80u) <= 0x3Fu &&
+		    (t2 = text[1] - 0x80u) <= 0x3Fu))
+	{
+	  c = ((c&0xFu)<<12) | (t1<<6) | t2;
+	  if (unlikely (c < 0x0800u || hb_in_range<hb_codepoint_t> (c, 0xD800u, 0xDFFFu)))
+	    goto error;
+	  text += 2;
+	}
+	else
+	  goto error;
+      }
+      else if (hb_in_range<hb_codepoint_t> (c, 0xF0u, 0xF4u)) /* Four-byte */
+      {
+	unsigned int t1, t2, t3;
+	if (likely (2 < end - text &&
+		    (t1 = text[0] - 0x80u) <= 0x3Fu &&
+		    (t2 = text[1] - 0x80u) <= 0x3Fu &&
+		    (t3 = text[2] - 0x80u) <= 0x3Fu))
+	{
+	  c = ((c&0x7u)<<18) | (t1<<12) | (t2<<6) | t3;
+	  if (unlikely (!hb_in_range<hb_codepoint_t> (c, 0x10000u, 0x10FFFFu)))
+	    goto error;
+	  text += 3;
+	}
+	else
+	  goto error;
+      }
+      else
+	goto error;
+    }
+
+    *unicode = c;
+    return text;
+
+  error:
+    *unicode = replacement;
+    return text;
+  }
+
+  static const codepoint_t *
+  prev (const codepoint_t *text,
+	const codepoint_t *start,
+	hb_codepoint_t *unicode,
+	hb_codepoint_t replacement)
+  {
+    const codepoint_t *end = text--;
+    while (start < text && (*text & 0xc0) == 0x80 && end - text < 4)
+      text--;
+
+    if (likely (next (text, end, unicode, replacement) == end))
+      return text;
+
+    *unicode = replacement;
+    return end - 1;
+  }
+
+  static unsigned int
+  strlen (const codepoint_t *text)
+  { return ::strlen ((const char *) text); }
+
+  static unsigned int
+  encode_len (hb_codepoint_t unicode)
+  {
+    if (unicode <   0x0080u) return 1;
+    if (unicode <   0x0800u) return 2;
+    if (unicode <  0x10000u) return 3;
+    if (unicode < 0x110000u) return 4;
+    return 3;
+  }
+
+  static codepoint_t *
+  encode (codepoint_t *text,
+	  const codepoint_t *end,
+	  hb_codepoint_t unicode)
+  {
+    if (unlikely (unicode >= 0xD800u && (unicode <= 0xDFFFu || unicode > 0x10FFFFu)))
+      unicode = 0xFFFDu;
+    if (unicode < 0x0080u)
+     *text++ = unicode;
+    else if (unicode < 0x0800u)
+    {
+      if (end - text >= 2)
+      {
+	*text++ =  0xC0u + (0x1Fu & (unicode >>  6));
+	*text++ =  0x80u + (0x3Fu & (unicode      ));
+      }
+    }
+    else if (unicode < 0x10000u)
+    {
+      if (end - text >= 3)
+      {
+	*text++ =  0xE0u + (0x0Fu & (unicode >> 12));
+	*text++ =  0x80u + (0x3Fu & (unicode >>  6));
+	*text++ =  0x80u + (0x3Fu & (unicode      ));
+      }
+    }
+    else
+    {
+      if (end - text >= 4)
+      {
+	*text++ =  0xF0u + (0x07u & (unicode >> 18));
+	*text++ =  0x80u + (0x3Fu & (unicode >> 12));
+	*text++ =  0x80u + (0x3Fu & (unicode >>  6));
+	*text++ =  0x80u + (0x3Fu & (unicode      ));
+      }
+    }
+    return text;
+  }
+};
+
+
+template <typename TCodepoint>
+struct hb_utf16_xe_t
+{
+  static_assert (sizeof (TCodepoint) == 2, "");
+  typedef TCodepoint codepoint_t;
+
+  static const codepoint_t *
+  next (const codepoint_t *text,
+	const codepoint_t *end,
+	hb_codepoint_t *unicode,
+	hb_codepoint_t replacement)
+  {
+    hb_codepoint_t c = *text++;
+
+    if (likely (!hb_in_range<hb_codepoint_t> (c, 0xD800u, 0xDFFFu)))
+    {
+      *unicode = c;
+      return text;
+    }
+
+    if (likely (c <= 0xDBFFu && text < end))
+    {
+      /* High-surrogate in c */
+      hb_codepoint_t l = *text;
+      if (likely (hb_in_range<hb_codepoint_t> (l, 0xDC00u, 0xDFFFu)))
+      {
+	/* Low-surrogate in l */
+	*unicode = (c << 10) + l - ((0xD800u << 10) - 0x10000u + 0xDC00u);
+	 text++;
+	 return text;
+      }
+    }
+
+    /* Lonely / out-of-order surrogate. */
+    *unicode = replacement;
+    return text;
+  }
+
+  static const codepoint_t *
+  prev (const codepoint_t *text,
+	const codepoint_t *start,
+	hb_codepoint_t *unicode,
+	hb_codepoint_t replacement)
+  {
+    hb_codepoint_t c = *--text;
+
+    if (likely (!hb_in_range<hb_codepoint_t> (c, 0xD800u, 0xDFFFu)))
+    {
+      *unicode = c;
+      return text;
+    }
+
+    if (likely (c >= 0xDC00u && start < text))
+    {
+      /* Low-surrogate in c */
+      hb_codepoint_t h = text[-1];
+      if (likely (hb_in_range<hb_codepoint_t> (h, 0xD800u, 0xDBFFu)))
+      {
+	/* High-surrogate in h */
+	*unicode = (h << 10) + c - ((0xD800u << 10) - 0x10000u + 0xDC00u);
+	text--;
+	return text;
+      }
+    }
+
+    /* Lonely / out-of-order surrogate. */
+    *unicode = replacement;
+    return text;
+  }
+
+
+  static unsigned int
+  strlen (const codepoint_t *text)
+  {
+    unsigned int l = 0;
+    while (*text++) l++;
+    return l;
+  }
+
+  static unsigned int
+  encode_len (hb_codepoint_t unicode)
+  {
+    return unicode < 0x10000 ? 1 : 2;
+  }
+
+  static codepoint_t *
+  encode (codepoint_t *text,
+	  const codepoint_t *end,
+	  hb_codepoint_t unicode)
+  {
+    if (unlikely (unicode >= 0xD800u && (unicode <= 0xDFFFu || unicode > 0x10FFFFu)))
+      unicode = 0xFFFDu;
+    if (unicode < 0x10000u)
+     *text++ = unicode;
+    else if (end - text >= 2)
+    {
+      unicode -= 0x10000u;
+      *text++ =  0xD800u + (unicode >> 10);
+      *text++ =  0xDC00u + (unicode & 0x03FFu);
+    }
+    return text;
+  }
+};
+
+typedef hb_utf16_xe_t<uint16_t> hb_utf16_t;
+typedef hb_utf16_xe_t<OT::HBUINT16> hb_utf16_be_t;
+
+
+template <typename TCodepoint, bool validate=true>
+struct hb_utf32_xe_t
+{
+  static_assert (sizeof (TCodepoint) == 4, "");
+  typedef TCodepoint codepoint_t;
+
+  static const TCodepoint *
+  next (const TCodepoint *text,
+	const TCodepoint *end HB_UNUSED,
+	hb_codepoint_t *unicode,
+	hb_codepoint_t replacement)
+  {
+    hb_codepoint_t c = *unicode = *text++;
+    if (validate && unlikely (c >= 0xD800u && (c <= 0xDFFFu || c > 0x10FFFFu)))
+      *unicode = replacement;
+    return text;
+  }
+
+  static const TCodepoint *
+  prev (const TCodepoint *text,
+	const TCodepoint *start HB_UNUSED,
+	hb_codepoint_t *unicode,
+	hb_codepoint_t replacement)
+  {
+    hb_codepoint_t c = *unicode = *--text;
+    if (validate && unlikely (c >= 0xD800u && (c <= 0xDFFFu || c > 0x10FFFFu)))
+      *unicode = replacement;
+    return text;
+  }
+
+  static unsigned int
+  strlen (const TCodepoint *text)
+  {
+    unsigned int l = 0;
+    while (*text++) l++;
+    return l;
+  }
+
+  static unsigned int
+  encode_len (hb_codepoint_t unicode HB_UNUSED)
+  {
+    return 1;
+  }
+
+  static codepoint_t *
+  encode (codepoint_t *text,
+	  const codepoint_t *end HB_UNUSED,
+	  hb_codepoint_t unicode)
+  {
+    if (validate && unlikely (unicode >= 0xD800u && (unicode <= 0xDFFFu || unicode > 0x10FFFFu)))
+      unicode = 0xFFFDu;
+    *text++ = unicode;
+    return text;
+  }
+};
+
+typedef hb_utf32_xe_t<uint32_t> hb_utf32_t;
+typedef hb_utf32_xe_t<uint32_t, false> hb_utf32_novalidate_t;
+
+
+struct hb_latin1_t
+{
+  typedef uint8_t codepoint_t;
+
+  static const codepoint_t *
+  next (const codepoint_t *text,
+	const codepoint_t *end HB_UNUSED,
+	hb_codepoint_t *unicode,
+	hb_codepoint_t replacement HB_UNUSED)
+  {
+    *unicode = *text++;
+    return text;
+  }
+
+  static const codepoint_t *
+  prev (const codepoint_t *text,
+	const codepoint_t *start HB_UNUSED,
+	hb_codepoint_t *unicode,
+	hb_codepoint_t replacement HB_UNUSED)
+  {
+    *unicode = *--text;
+    return text;
+  }
+
+  static unsigned int
+  strlen (const codepoint_t *text)
+  {
+    unsigned int l = 0;
+    while (*text++) l++;
+    return l;
+  }
+
+  static unsigned int
+  encode_len (hb_codepoint_t unicode HB_UNUSED)
+  {
+    return 1;
+  }
+
+  static codepoint_t *
+  encode (codepoint_t *text,
+	  const codepoint_t *end HB_UNUSED,
+	  hb_codepoint_t unicode)
+  {
+    if (unlikely (unicode >= 0x0100u))
+      unicode = '?';
+    *text++ = unicode;
+    return text;
+  }
+};
+
+
+struct hb_ascii_t
+{
+  typedef uint8_t codepoint_t;
+
+  static const codepoint_t *
+  next (const codepoint_t *text,
+	const codepoint_t *end HB_UNUSED,
+	hb_codepoint_t *unicode,
+	hb_codepoint_t replacement HB_UNUSED)
+  {
+    *unicode = *text++;
+    if (*unicode >= 0x0080u)
+      *unicode = replacement;
+    return text;
+  }
+
+  static const codepoint_t *
+  prev (const codepoint_t *text,
+	const codepoint_t *start HB_UNUSED,
+	hb_codepoint_t *unicode,
+	hb_codepoint_t replacement)
+  {
+    *unicode = *--text;
+    if (*unicode >= 0x0080u)
+      *unicode = replacement;
+    return text;
+  }
+
+  static unsigned int
+  strlen (const codepoint_t *text)
+  {
+    unsigned int l = 0;
+    while (*text++) l++;
+    return l;
+  }
+
+  static unsigned int
+  encode_len (hb_codepoint_t unicode HB_UNUSED)
+  {
+    return 1;
+  }
+
+  static codepoint_t *
+  encode (codepoint_t *text,
+	  const codepoint_t *end HB_UNUSED,
+	  hb_codepoint_t unicode)
+  {
+    if (unlikely (unicode >= 0x0080u))
+      unicode = '?';
+    *text++ = unicode;
+    return text;
+  }
+};
+
+#endif /* HB_UTF_HH */