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diff --git a/src/cairo-unicode.c b/src/cairo-unicode.c
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+/* -*- Mode: c; c-basic-offset: 4; indent-tabs-mode: t; tab-width: 8; -*- */
+/* cairo - a vector graphics library with display and print output
+ *
+ * The code in this file is derived from GLib's gutf8.c and
+ * ultimately from libunicode. It is relicensed under the
+ * dual LGPL/MPL with permission of the original authors.
+ *
+ * Copyright © 1999 Tom Tromey
+ * Copyright © 2005 Red Hat, Inc
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it either under the terms of the GNU Lesser General Public
+ * License version 2.1 as published by the Free Software Foundation
+ * (the "LGPL") or, at your option, under the terms of the Mozilla
+ * Public License Version 1.1 (the "MPL"). If you do not alter this
+ * notice, a recipient may use your version of this file under either
+ * the MPL or the LGPL.
+ *
+ * You should have received a copy of the LGPL along with this library
+ * in the file COPYING-LGPL-2.1; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
+ * You should have received a copy of the MPL along with this library
+ * in the file COPYING-MPL-1.1
+ *
+ * The contents of this file are subject to the Mozilla Public License
+ * Version 1.1 (the "License"); you may not use this file except in
+ * compliance with the License. You may obtain a copy of the License at
+ * http://www.mozilla.org/MPL/
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
+ * OF ANY KIND, either express or implied. See the LGPL or the MPL for
+ * the specific language governing rights and limitations.
+ *
+ * The Original Code is the cairo graphics library.
+ *
+ * The Initial Developer of the Original Code is Tom Tromey.
+ * and Red Hat, Inc.
+ *
+ * Contributor(s):
+ * Owen Taylor <otaylor@redhat.com>
+ */
+
+#include "cairoint.h"
+#include "cairo-error-private.h"
+
+#define UTF8_COMPUTE(Char, Mask, Len) \
+ if (Char < 128) \
+ { \
+ Len = 1; \
+ Mask = 0x7f; \
+ } \
+ else if ((Char & 0xe0) == 0xc0) \
+ { \
+ Len = 2; \
+ Mask = 0x1f; \
+ } \
+ else if ((Char & 0xf0) == 0xe0) \
+ { \
+ Len = 3; \
+ Mask = 0x0f; \
+ } \
+ else if ((Char & 0xf8) == 0xf0) \
+ { \
+ Len = 4; \
+ Mask = 0x07; \
+ } \
+ else if ((Char & 0xfc) == 0xf8) \
+ { \
+ Len = 5; \
+ Mask = 0x03; \
+ } \
+ else if ((Char & 0xfe) == 0xfc) \
+ { \
+ Len = 6; \
+ Mask = 0x01; \
+ } \
+ else \
+ Len = -1;
+
+#define UTF8_LENGTH(Char) \
+ ((Char) < 0x80 ? 1 : \
+ ((Char) < 0x800 ? 2 : \
+ ((Char) < 0x10000 ? 3 : \
+ ((Char) < 0x200000 ? 4 : \
+ ((Char) < 0x4000000 ? 5 : 6)))))
+
+#define UTF8_GET(Result, Chars, Count, Mask, Len) \
+ (Result) = (Chars)[0] & (Mask); \
+ for ((Count) = 1; (Count) < (Len); ++(Count)) \
+ { \
+ if (((Chars)[(Count)] & 0xc0) != 0x80) \
+ { \
+ (Result) = -1; \
+ break; \
+ } \
+ (Result) <<= 6; \
+ (Result) |= ((Chars)[(Count)] & 0x3f); \
+ }
+
+#define UNICODE_VALID(Char) \
+ ((Char) < 0x110000 && \
+ (((Char) & 0xFFFFF800) != 0xD800) && \
+ ((Char) < 0xFDD0 || (Char) > 0xFDEF) && \
+ ((Char) & 0xFFFE) != 0xFFFE)
+
+static const char utf8_skip_data[256] = {
+ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+ 1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
+ 2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,2,
+ 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,6,6,1,1
+};
+
+#define UTF8_NEXT_CHAR(p) ((p) + utf8_skip_data[*(unsigned char *)(p)])
+
+/* Converts a sequence of bytes encoded as UTF-8 to a Unicode character.
+ * If @p does not point to a valid UTF-8 encoded character, results are
+ * undefined.
+ **/
+static uint32_t
+_utf8_get_char (const unsigned char *p)
+{
+ int i, mask = 0, len;
+ uint32_t result;
+ unsigned char c = (unsigned char) *p;
+
+ UTF8_COMPUTE (c, mask, len);
+ if (len == -1)
+ return (uint32_t)-1;
+ UTF8_GET (result, p, i, mask, len);
+
+ return result;
+}
+
+/* Like _utf8_get_char, but take a maximum length
+ * and return (uint32_t)-2 on incomplete trailing character
+ */
+static uint32_t
+_utf8_get_char_extended (const unsigned char *p,
+ long max_len)
+{
+ int i, len;
+ uint32_t wc = (unsigned char) *p;
+
+ if (wc < 0x80) {
+ return wc;
+ } else if (wc < 0xc0) {
+ return (uint32_t)-1;
+ } else if (wc < 0xe0) {
+ len = 2;
+ wc &= 0x1f;
+ } else if (wc < 0xf0) {
+ len = 3;
+ wc &= 0x0f;
+ } else if (wc < 0xf8) {
+ len = 4;
+ wc &= 0x07;
+ } else if (wc < 0xfc) {
+ len = 5;
+ wc &= 0x03;
+ } else if (wc < 0xfe) {
+ len = 6;
+ wc &= 0x01;
+ } else {
+ return (uint32_t)-1;
+ }
+
+ if (max_len >= 0 && len > max_len) {
+ for (i = 1; i < max_len; i++) {
+ if ((((unsigned char *)p)[i] & 0xc0) != 0x80)
+ return (uint32_t)-1;
+ }
+ return (uint32_t)-2;
+ }
+
+ for (i = 1; i < len; ++i) {
+ uint32_t ch = ((unsigned char *)p)[i];
+
+ if ((ch & 0xc0) != 0x80) {
+ if (ch)
+ return (uint32_t)-1;
+ else
+ return (uint32_t)-2;
+ }
+
+ wc <<= 6;
+ wc |= (ch & 0x3f);
+ }
+
+ if (UTF8_LENGTH(wc) != len)
+ return (uint32_t)-1;
+
+ return wc;
+}
+
+/**
+ * _cairo_utf8_get_char_validated:
+ * @p: a UTF-8 string
+ * @unicode: location to store one Unicode character
+ *
+ * Decodes the first character of a valid UTF-8 string, and returns
+ * the number of bytes consumed.
+ *
+ * Note that the string should be valid. Do not use this without
+ * validating the string first.
+ *
+ * Returns: the number of bytes forming the character returned.
+ **/
+int
+_cairo_utf8_get_char_validated (const char *p,
+ uint32_t *unicode)
+{
+ int i, mask = 0, len;
+ uint32_t result;
+ unsigned char c = (unsigned char) *p;
+
+ UTF8_COMPUTE (c, mask, len);
+ if (len == -1) {
+ if (unicode)
+ *unicode = (uint32_t)-1;
+ return 1;
+ }
+ UTF8_GET (result, p, i, mask, len);
+
+ if (unicode)
+ *unicode = result;
+ return len;
+}
+
+/**
+ * _cairo_utf8_to_ucs4:
+ * @str: an UTF-8 string
+ * @len: length of @str in bytes, or -1 if it is nul-terminated.
+ * If @len is supplied and the string has an embedded nul
+ * byte, only the portion before the nul byte is converted.
+ * @result: location to store a pointer to a newly allocated UTF-32
+ * string (always native endian), or %NULL. Free with free(). A 0
+ * word will be written after the last character.
+ * @items_written: location to store number of 32-bit words
+ * written. (Not including the trailing 0)
+ *
+ * Converts a UTF-8 string to UCS-4. UCS-4 is an encoding of Unicode
+ * with 1 32-bit word per character. The string is validated to
+ * consist entirely of valid Unicode characters.
+ *
+ * Return value: %CAIRO_STATUS_SUCCESS if the entire string was
+ * successfully converted. %CAIRO_STATUS_INVALID_STRING if an
+ * invalid sequence was found.
+ **/
+cairo_status_t
+_cairo_utf8_to_ucs4 (const char *str,
+ int len,
+ uint32_t **result,
+ int *items_written)
+{
+ uint32_t *str32 = NULL;
+ int n_chars, i;
+ const unsigned char *in;
+ const unsigned char * const ustr = (const unsigned char *) str;
+
+ in = ustr;
+ n_chars = 0;
+ while ((len < 0 || ustr + len - in > 0) && *in)
+ {
+ uint32_t wc = _utf8_get_char_extended (in, ustr + len - in);
+ if (wc & 0x80000000 || !UNICODE_VALID (wc))
+ return _cairo_error (CAIRO_STATUS_INVALID_STRING);
+
+ n_chars++;
+ if (n_chars == INT_MAX)
+ return _cairo_error (CAIRO_STATUS_INVALID_STRING);
+
+ in = UTF8_NEXT_CHAR (in);
+ }
+
+ if (result) {
+ str32 = _cairo_malloc_ab (n_chars + 1, sizeof (uint32_t));
+ if (!str32)
+ return _cairo_error (CAIRO_STATUS_NO_MEMORY);
+
+ in = ustr;
+ for (i=0; i < n_chars; i++) {
+ str32[i] = _utf8_get_char (in);
+ in = UTF8_NEXT_CHAR (in);
+ }
+ str32[i] = 0;
+
+ *result = str32;
+ }
+
+ if (items_written)
+ *items_written = n_chars;
+
+ return CAIRO_STATUS_SUCCESS;
+}
+
+/**
+ * _cairo_ucs4_to_utf8:
+ * @unicode: a UCS-4 character
+ * @utf8: buffer to write utf8 string into. Must have at least 4 bytes
+ * space available. Or %NULL.
+ *
+ * This space left intentionally blank.
+ *
+ * Return value: Number of bytes in the utf8 string or 0 if an invalid
+ * unicode character
+ **/
+int
+_cairo_ucs4_to_utf8 (uint32_t unicode,
+ char *utf8)
+{
+ int bytes;
+ char *p;
+
+ if (unicode < 0x80) {
+ if (utf8)
+ *utf8 = unicode;
+ return 1;
+ } else if (unicode < 0x800) {
+ bytes = 2;
+ } else if (unicode < 0x10000) {
+ bytes = 3;
+ } else if (unicode < 0x200000) {
+ bytes = 4;
+ } else {
+ return 0;
+ }
+
+ if (!utf8)
+ return bytes;
+
+ p = utf8 + bytes;
+ while (p > utf8) {
+ *--p = 0x80 | (unicode & 0x3f);
+ unicode >>= 6;
+ }
+ *p |= 0xf0 << (4 - bytes);
+
+ return bytes;
+}
+
+#if CAIRO_HAS_UTF8_TO_UTF16
+/**
+ * _cairo_utf8_to_utf16:
+ * @str: an UTF-8 string
+ * @len: length of @str in bytes, or -1 if it is nul-terminated.
+ * If @len is supplied and the string has an embedded nul
+ * byte, only the portion before the nul byte is converted.
+ * @result: location to store a pointer to a newly allocated UTF-16
+ * string (always native endian). Free with free(). A 0
+ * word will be written after the last character.
+ * @items_written: location to store number of 16-bit words
+ * written. (Not including the trailing 0)
+ *
+ * Converts a UTF-8 string to UTF-16. UTF-16 is an encoding of Unicode
+ * where characters are represented either as a single 16-bit word, or
+ * as a pair of 16-bit "surrogates". The string is validated to
+ * consist entirely of valid Unicode characters.
+ *
+ * Return value: %CAIRO_STATUS_SUCCESS if the entire string was
+ * successfully converted. %CAIRO_STATUS_INVALID_STRING if an
+ * an invalid sequence was found.
+ **/
+cairo_status_t
+_cairo_utf8_to_utf16 (const char *str,
+ int len,
+ uint16_t **result,
+ int *items_written)
+{
+ uint16_t *str16 = NULL;
+ int n16, i;
+ const unsigned char *in;
+ const unsigned char * const ustr = (const unsigned char *) str;
+
+ in = ustr;
+ n16 = 0;
+ while ((len < 0 || ustr + len - in > 0) && *in) {
+ uint32_t wc = _utf8_get_char_extended (in, ustr + len - in);
+ if (wc & 0x80000000 || !UNICODE_VALID (wc))
+ return _cairo_error (CAIRO_STATUS_INVALID_STRING);
+
+ if (wc < 0x10000)
+ n16 += 1;
+ else
+ n16 += 2;
+
+ if (n16 == INT_MAX - 1 || n16 == INT_MAX)
+ return _cairo_error (CAIRO_STATUS_INVALID_STRING);
+
+ in = UTF8_NEXT_CHAR (in);
+ }
+
+ str16 = _cairo_malloc_ab (n16 + 1, sizeof (uint16_t));
+ if (!str16)
+ return _cairo_error (CAIRO_STATUS_NO_MEMORY);
+
+ in = ustr;
+ for (i = 0; i < n16;) {
+ uint32_t wc = _utf8_get_char (in);
+
+ if (wc < 0x10000) {
+ str16[i++] = wc;
+ } else {
+ str16[i++] = (wc - 0x10000) / 0x400 + 0xd800;
+ str16[i++] = (wc - 0x10000) % 0x400 + 0xdc00;
+ }
+
+ in = UTF8_NEXT_CHAR (in);
+ }
+
+ str16[i] = 0;
+
+ *result = str16;
+ if (items_written)
+ *items_written = n16;
+
+ return CAIRO_STATUS_SUCCESS;
+}
+#endif