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/* gutf8.c - Operations on UTF-8 strings.
*
* Copyright (C) 1999 Tom Tromey
* Copyright (C) 2000 Red Hat, Inc.
*
* SPDX-License-Identifier: LGPL-2.1-or-later
*
* This library 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 2.1 of the License, or (at your option) any later version.
*
* This library 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 library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "config.h"
#include <stdlib.h>
#ifdef HAVE_CODESET
#include <langinfo.h>
#endif
#include <string.h>
#ifdef G_PLATFORM_WIN32
#include <stdio.h>
#define STRICT
#include <windows.h>
#undef STRICT
#endif
#include "gconvert.h"
#include "ghash.h"
#include "gstrfuncs.h"
#include "gtestutils.h"
#include "gtypes.h"
#include "gthread.h"
#include "glibintl.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); \
}
/*
* Check whether a Unicode (5.2) char is in a valid range.
*
* The first check comes from the Unicode guarantee to never encode
* a point above 0x0010ffff, since UTF-16 couldn't represent it.
*
* The second check covers surrogate pairs (category Cs).
*
* @param Char the character
*/
#define UNICODE_VALID(Char) \
((Char) < 0x110000 && \
(((Char) & 0xFFFFF800) != 0xD800))
static const gchar 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
};
const gchar * const g_utf8_skip = utf8_skip_data;
/**
* g_utf8_find_prev_char:
* @str: pointer to the beginning of a UTF-8 encoded string
* @p: pointer to some position within @str
*
* Given a position @p with a UTF-8 encoded string @str, find the start
* of the previous UTF-8 character starting before @p. Returns %NULL if no
* UTF-8 characters are present in @str before @p.
*
* @p does not have to be at the beginning of a UTF-8 character. No check
* is made to see if the character found is actually valid other than
* it starts with an appropriate byte.
*
* Returns: (transfer none) (nullable): a pointer to the found character or %NULL.
*/
gchar *
g_utf8_find_prev_char (const gchar *str,
const gchar *p)
{
while (p > str)
{
--p;
if ((*p & 0xc0) != 0x80)
return (gchar *)p;
}
return NULL;
}
/**
* g_utf8_find_next_char:
* @p: a pointer to a position within a UTF-8 encoded string
* @end: (nullable): a pointer to the byte following the end of the string,
* or %NULL to indicate that the string is nul-terminated
*
* Finds the start of the next UTF-8 character in the string after @p.
*
* @p does not have to be at the beginning of a UTF-8 character. No check
* is made to see if the character found is actually valid other than
* it starts with an appropriate byte.
*
* If @end is %NULL, the return value will never be %NULL: if the end of the
* string is reached, a pointer to the terminating nul byte is returned. If
* @end is non-%NULL, the return value will be %NULL if the end of the string
* is reached.
*
* Returns: (transfer none) (nullable): a pointer to the found character or %NULL if @end is
* set and is reached
*/
gchar *
g_utf8_find_next_char (const gchar *p,
const gchar *end)
{
if (end)
{
for (++p; p < end && (*p & 0xc0) == 0x80; ++p)
;
return (p >= end) ? NULL : (gchar *)p;
}
else
{
for (++p; (*p & 0xc0) == 0x80; ++p)
;
return (gchar *)p;
}
}
/**
* g_utf8_prev_char:
* @p: a pointer to a position within a UTF-8 encoded string
*
* Finds the previous UTF-8 character in the string before @p.
*
* @p does not have to be at the beginning of a UTF-8 character. No check
* is made to see if the character found is actually valid other than
* it starts with an appropriate byte. If @p might be the first
* character of the string, you must use g_utf8_find_prev_char() instead.
*
* Returns: (transfer none) (not nullable): a pointer to the found character
*/
gchar *
g_utf8_prev_char (const gchar *p)
{
while (TRUE)
{
p--;
if ((*p & 0xc0) != 0x80)
return (gchar *)p;
}
}
/**
* g_utf8_strlen:
* @p: pointer to the start of a UTF-8 encoded string
* @max: the maximum number of bytes to examine. If @max
* is less than 0, then the string is assumed to be
* nul-terminated. If @max is 0, @p will not be examined and
* may be %NULL. If @max is greater than 0, up to @max
* bytes are examined
*
* Computes the length of the string in characters, not including
* the terminating nul character. If the @max'th byte falls in the
* middle of a character, the last (partial) character is not counted.
*
* Returns: the length of the string in characters
*/
glong
g_utf8_strlen (const gchar *p,
gssize max)
{
glong len = 0;
const gchar *start = p;
g_return_val_if_fail (p != NULL || max == 0, 0);
if (max < 0)
{
while (*p)
{
p = g_utf8_next_char (p);
++len;
}
}
else
{
if (max == 0 || !*p)
return 0;
p = g_utf8_next_char (p);
while (p - start < max && *p)
{
++len;
p = g_utf8_next_char (p);
}
/* only do the last len increment if we got a complete
* char (don't count partial chars)
*/
if (p - start <= max)
++len;
}
return len;
}
/**
* g_utf8_substring:
* @str: a UTF-8 encoded string
* @start_pos: a character offset within @str
* @end_pos: another character offset within @str,
* or `-1` to indicate the end of the string
*
* Copies a substring out of a UTF-8 encoded string.
* The substring will contain @end_pos - @start_pos characters.
*
* Since GLib 2.72, `-1` can be passed to @end_pos to indicate the
* end of the string.
*
* Returns: (transfer full): a newly allocated copy of the requested
* substring. Free with g_free() when no longer needed.
*
* Since: 2.30
*/
gchar *
g_utf8_substring (const gchar *str,
glong start_pos,
glong end_pos)
{
gchar *start, *end, *out;
g_return_val_if_fail (end_pos >= start_pos || end_pos == -1, NULL);
start = g_utf8_offset_to_pointer (str, start_pos);
if (end_pos == -1)
{
glong length = g_utf8_strlen (start, -1);
end = g_utf8_offset_to_pointer (start, length);
}
else
{
end = g_utf8_offset_to_pointer (start, end_pos - start_pos);
}
out = g_malloc (end - start + 1);
memcpy (out, start, end - start);
out[end - start] = 0;
return out;
}
/**
* g_utf8_get_char:
* @p: a pointer to Unicode character encoded as UTF-8
*
* 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. If you are not sure that the bytes are complete
* valid Unicode characters, you should use g_utf8_get_char_validated()
* instead.
*
* Returns: the resulting character
*/
gunichar
g_utf8_get_char (const gchar *p)
{
int i, mask = 0, len;
gunichar result;
unsigned char c = (unsigned char) *p;
UTF8_COMPUTE (c, mask, len);
if (len == -1)
return (gunichar)-1;
UTF8_GET (result, p, i, mask, len);
return result;
}
/**
* g_utf8_offset_to_pointer:
* @str: a UTF-8 encoded string
* @offset: a character offset within @str
*
* Converts from an integer character offset to a pointer to a position
* within the string.
*
* Since 2.10, this function allows to pass a negative @offset to
* step backwards. It is usually worth stepping backwards from the end
* instead of forwards if @offset is in the last fourth of the string,
* since moving forward is about 3 times faster than moving backward.
*
* Note that this function doesn't abort when reaching the end of @str.
* Therefore you should be sure that @offset is within string boundaries
* before calling that function. Call g_utf8_strlen() when unsure.
* This limitation exists as this function is called frequently during
* text rendering and therefore has to be as fast as possible.
*
* Returns: (transfer none): the resulting pointer
*/
gchar *
g_utf8_offset_to_pointer (const gchar *str,
glong offset)
{
const gchar *s = str;
if (offset > 0)
while (offset--)
s = g_utf8_next_char (s);
else
{
const char *s1;
/* This nice technique for fast backwards stepping
* through a UTF-8 string was dubbed "stutter stepping"
* by its inventor, Larry Ewing.
*/
while (offset)
{
s1 = s;
s += offset;
while ((*s & 0xc0) == 0x80)
s--;
offset += g_utf8_pointer_to_offset (s, s1);
}
}
return (gchar *)s;
}
/**
* g_utf8_pointer_to_offset:
* @str: a UTF-8 encoded string
* @pos: a pointer to a position within @str
*
* Converts from a pointer to position within a string to an integer
* character offset.
*
* Since 2.10, this function allows @pos to be before @str, and returns
* a negative offset in this case.
*
* Returns: the resulting character offset
*/
glong
g_utf8_pointer_to_offset (const gchar *str,
const gchar *pos)
{
const gchar *s = str;
glong offset = 0;
if (pos < str)
offset = - g_utf8_pointer_to_offset (pos, str);
else
while (s < pos)
{
s = g_utf8_next_char (s);
offset++;
}
return offset;
}
/**
* g_utf8_strncpy:
* @dest: (transfer none): buffer to fill with characters from @src
* @src: UTF-8 encoded string
* @n: character count
*
* Like the standard C strncpy() function, but copies a given number
* of characters instead of a given number of bytes. The @src string
* must be valid UTF-8 encoded text. (Use g_utf8_validate() on all
* text before trying to use UTF-8 utility functions with it.)
*
* Note you must ensure @dest is at least 4 * @n + 1 to fit the
* largest possible UTF-8 characters
*
* Returns: (transfer none): @dest
*/
gchar *
g_utf8_strncpy (gchar *dest,
const gchar *src,
gsize n)
{
const gchar *s = src;
while (n && *s)
{
s = g_utf8_next_char(s);
n--;
}
strncpy(dest, src, s - src);
dest[s - src] = 0;
return dest;
}
/**
* g_utf8_truncate_middle:
* @string: (transfer none): a nul-terminated UTF-8 encoded string
* @truncate_length: the new size of @string, in characters, including the ellipsis character
*
* Cuts off the middle of the string, preserving half of @truncate_length
* characters at the beginning and half at the end.
*
* If @string is already short enough, this returns a copy of @string.
* If @truncate_length is `0`, an empty string is returned.
*
* Returns: (transfer full): a newly-allocated copy of @string ellipsized in the middle
*
* Since: 2.78
*/
gchar *
g_utf8_truncate_middle (const gchar *string,
gsize truncate_length)
{
const gchar *ellipsis = "…";
const gsize ellipsis_bytes = strlen (ellipsis);
gsize length;
gsize left_substring_length;
gchar *left_substring_end;
gchar *right_substring_begin;
gchar *right_substring_end;
gsize left_bytes;
gsize right_bytes;
gchar *result;
g_return_val_if_fail (string != NULL, NULL);
length = g_utf8_strlen (string, -1);
/* Current string already smaller than requested length */
if (length <= truncate_length)
return g_strdup (string);
if (truncate_length == 0)
return g_strdup ("");
/* Find substrings to keep, ignore ellipsis character for that */
truncate_length -= 1;
left_substring_length = truncate_length / 2;
left_substring_end = g_utf8_offset_to_pointer (string, left_substring_length);
right_substring_begin = g_utf8_offset_to_pointer (left_substring_end,
length - truncate_length);
right_substring_end = g_utf8_offset_to_pointer (right_substring_begin,
truncate_length - left_substring_length);
g_assert (*right_substring_end == '\0');
left_bytes = left_substring_end - string;
right_bytes = right_substring_end - right_substring_begin;
result = g_malloc (left_bytes + ellipsis_bytes + right_bytes + 1);
strncpy (result, string, left_bytes);
memcpy (result + left_bytes, ellipsis, ellipsis_bytes);
strncpy (result + left_bytes + ellipsis_bytes, right_substring_begin, right_bytes);
result[left_bytes + ellipsis_bytes + right_bytes] = '\0';
return result;
}
/* unicode_strchr */
/**
* g_unichar_to_utf8:
* @c: a Unicode character code
* @outbuf: (out caller-allocates) (optional): output buffer, must have at
* least 6 bytes of space. If %NULL, the length will be computed and
* returned and nothing will be written to @outbuf.
*
* Converts a single character to UTF-8.
*
* Returns: number of bytes written
*/
int
g_unichar_to_utf8 (gunichar c,
gchar *outbuf)
{
/* If this gets modified, also update the copy in g_string_insert_unichar() */
guint len = 0;
int first;
int i;
if (c < 0x80)
{
first = 0;
len = 1;
}
else if (c < 0x800)
{
first = 0xc0;
len = 2;
}
else if (c < 0x10000)
{
first = 0xe0;
len = 3;
}
else if (c < 0x200000)
{
first = 0xf0;
len = 4;
}
else if (c < 0x4000000)
{
first = 0xf8;
len = 5;
}
else
{
first = 0xfc;
len = 6;
}
if (outbuf)
{
for (i = len - 1; i > 0; --i)
{
outbuf[i] = (c & 0x3f) | 0x80;
c >>= 6;
}
outbuf[0] = c | first;
}
return len;
}
/**
* g_utf8_strchr:
* @p: a nul-terminated UTF-8 encoded string
* @len: the maximum length of @p
* @c: a Unicode character
*
* Finds the leftmost occurrence of the given Unicode character
* in a UTF-8 encoded string, while limiting the search to @len bytes.
* If @len is -1, allow unbounded search.
*
* Returns: (transfer none) (nullable): %NULL if the string does not contain the character,
* otherwise, a pointer to the start of the leftmost occurrence
* of the character in the string.
*/
gchar *
g_utf8_strchr (const char *p,
gssize len,
gunichar c)
{
gchar ch[10];
gint charlen = g_unichar_to_utf8 (c, ch);
ch[charlen] = '\0';
return g_strstr_len (p, len, ch);
}
/**
* g_utf8_strrchr:
* @p: a nul-terminated UTF-8 encoded string
* @len: the maximum length of @p
* @c: a Unicode character
*
* Find the rightmost occurrence of the given Unicode character
* in a UTF-8 encoded string, while limiting the search to @len bytes.
* If @len is -1, allow unbounded search.
*
* Returns: (transfer none) (nullable): %NULL if the string does not contain the character,
* otherwise, a pointer to the start of the rightmost occurrence
* of the character in the string.
*/
gchar *
g_utf8_strrchr (const char *p,
gssize len,
gunichar c)
{
gchar ch[10];
gint charlen = g_unichar_to_utf8 (c, ch);
ch[charlen] = '\0';
return g_strrstr_len (p, len, ch);
}
/* Like g_utf8_get_char, but take a maximum length
* and return (gunichar)-2 on incomplete trailing character;
* also check for malformed or overlong sequences
* and return (gunichar)-1 in this case.
*/
static inline gunichar
g_utf8_get_char_extended (const gchar *p,
gssize max_len)
{
gsize i, len;
gunichar min_code;
gunichar wc = (guchar) *p;
const gunichar partial_sequence = (gunichar) -2;
const gunichar malformed_sequence = (gunichar) -1;
if (wc < 0x80)
{
return wc;
}
else if (G_UNLIKELY (wc < 0xc0))
{
return malformed_sequence;
}
else if (wc < 0xe0)
{
len = 2;
wc &= 0x1f;
min_code = 1 << 7;
}
else if (wc < 0xf0)
{
len = 3;
wc &= 0x0f;
min_code = 1 << 11;
}
else if (wc < 0xf8)
{
len = 4;
wc &= 0x07;
min_code = 1 << 16;
}
else if (wc < 0xfc)
{
len = 5;
wc &= 0x03;
min_code = 1 << 21;
}
else if (wc < 0xfe)
{
len = 6;
wc &= 0x01;
min_code = 1 << 26;
}
else
{
return malformed_sequence;
}
if (G_UNLIKELY (max_len >= 0 && len > (gsize) max_len))
{
for (i = 1; i < (gsize) max_len; i++)
{
if ((((guchar *)p)[i] & 0xc0) != 0x80)
return malformed_sequence;
}
return partial_sequence;
}
for (i = 1; i < len; ++i)
{
gunichar ch = ((guchar *)p)[i];
if (G_UNLIKELY ((ch & 0xc0) != 0x80))
{
if (ch)
return malformed_sequence;
else
return partial_sequence;
}
wc <<= 6;
wc |= (ch & 0x3f);
}
if (G_UNLIKELY (wc < min_code))
return malformed_sequence;
return wc;
}
/**
* g_utf8_get_char_validated:
* @p: a pointer to Unicode character encoded as UTF-8
* @max_len: the maximum number of bytes to read, or -1 if @p is nul-terminated
*
* Convert a sequence of bytes encoded as UTF-8 to a Unicode character.
* This function checks for incomplete characters, for invalid characters
* such as characters that are out of the range of Unicode, and for
* overlong encodings of valid characters.
*
* Note that g_utf8_get_char_validated() returns (gunichar)-2 if
* @max_len is positive and any of the bytes in the first UTF-8 character
* sequence are nul.
*
* Returns: the resulting character. If @p points to a partial
* sequence at the end of a string that could begin a valid
* character (or if @max_len is zero), returns (gunichar)-2;
* otherwise, if @p does not point to a valid UTF-8 encoded
* Unicode character, returns (gunichar)-1.
*/
gunichar
g_utf8_get_char_validated (const gchar *p,
gssize max_len)
{
gunichar result;
if (max_len == 0)
return (gunichar)-2;
result = g_utf8_get_char_extended (p, max_len);
/* Disallow codepoint U+0000 as it’s a nul byte,
* and all string handling in GLib is nul-terminated */
if (result == 0 && max_len > 0)
return (gunichar) -2;
if (result & 0x80000000)
return result;
else if (!UNICODE_VALID (result))
return (gunichar)-1;
else
return result;
}
#define CONT_BYTE_FAST(p) ((guchar)*p++ & 0x3f)
/**
* g_utf8_to_ucs4_fast:
* @str: a UTF-8 encoded string
* @len: the maximum length of @str to use, in bytes. If @len < 0,
* then the string is nul-terminated.
* @items_written: (out) (optional): location to store the
* number of characters in the result, or %NULL.
*
* Convert a string from UTF-8 to a 32-bit fixed width
* representation as UCS-4, assuming valid UTF-8 input.
* This function is roughly twice as fast as g_utf8_to_ucs4()
* but does no error checking on the input. A trailing 0 character
* will be added to the string after the converted text.
*
* Returns: (transfer full): a pointer to a newly allocated UCS-4 string.
* This value must be freed with g_free().
*/
gunichar *
g_utf8_to_ucs4_fast (const gchar *str,
glong len,
glong *items_written)
{
gunichar *result;
gint n_chars, i;
const gchar *p;
g_return_val_if_fail (str != NULL, NULL);
p = str;
n_chars = 0;
if (len < 0)
{
while (*p)
{
p = g_utf8_next_char (p);
++n_chars;
}
}
else
{
while (p < str + len && *p)
{
p = g_utf8_next_char (p);
++n_chars;
}
}
result = g_new (gunichar, n_chars + 1);
p = str;
for (i=0; i < n_chars; i++)
{
guchar first = (guchar)*p++;
gunichar wc;
if (first < 0xc0)
{
/* We really hope first < 0x80, but we don't want to test an
* extra branch for invalid input, which this function
* does not care about. Handling unexpected continuation bytes
* here will do the least damage. */
wc = first;
}
else
{
gunichar c1 = CONT_BYTE_FAST(p);
if (first < 0xe0)
{
wc = ((first & 0x1f) << 6) | c1;
}
else
{
gunichar c2 = CONT_BYTE_FAST(p);
if (first < 0xf0)
{
wc = ((first & 0x0f) << 12) | (c1 << 6) | c2;
}
else
{
gunichar c3 = CONT_BYTE_FAST(p);
wc = ((first & 0x07) << 18) | (c1 << 12) | (c2 << 6) | c3;
if (G_UNLIKELY (first >= 0xf8))
{
/* This can't be valid UTF-8, but g_utf8_next_char()
* and company allow out-of-range sequences */
gunichar mask = 1 << 20;
while ((wc & mask) != 0)
{
wc <<= 6;
wc |= CONT_BYTE_FAST(p);
mask <<= 5;
}
wc &= mask - 1;
}
}
}
}
result[i] = wc;
}
result[i] = 0;
if (items_written)
*items_written = i;
return result;
}
static gpointer
try_malloc_n (gsize n_blocks, gsize n_block_bytes, GError **error)
{
gpointer ptr = g_try_malloc_n (n_blocks, n_block_bytes);
if (ptr == NULL)
g_set_error_literal (error, G_CONVERT_ERROR, G_CONVERT_ERROR_NO_MEMORY,
_("Failed to allocate memory"));
return ptr;
}
/**
* g_utf8_to_ucs4:
* @str: a UTF-8 encoded string
* @len: the maximum length of @str to use, in bytes. If @len < 0,
* then the string is nul-terminated.
* @items_read: (out) (optional): location to store number of
* bytes read, or %NULL.
* If %NULL, then %G_CONVERT_ERROR_PARTIAL_INPUT will be
* returned in case @str contains a trailing partial
* character. If an error occurs then the index of the
* invalid input is stored here.
* @items_written: (out) (optional): location to store number
* of characters written or %NULL. The value here stored does not include
* the trailing 0 character.
* @error: location to store the error occurring, or %NULL to ignore
* errors. Any of the errors in #GConvertError other than
* %G_CONVERT_ERROR_NO_CONVERSION may occur.
*
* Convert a string from UTF-8 to a 32-bit fixed width
* representation as UCS-4. A trailing 0 character will be added to the
* string after the converted text.
*
* Returns: (transfer full): a pointer to a newly allocated UCS-4 string.
* This value must be freed with g_free(). If an error occurs,
* %NULL will be returned and @error set.
*/
gunichar *
g_utf8_to_ucs4 (const gchar *str,
glong len,
glong *items_read,
glong *items_written,
GError **error)
{
gunichar *result = NULL;
gint n_chars, i;
const gchar *in;
in = str;
n_chars = 0;
while ((len < 0 || str + len - in > 0) && *in)
{
gunichar wc = g_utf8_get_char_extended (in, len < 0 ? 6 : str + len - in);
if (wc & 0x80000000)
{
if (wc == (gunichar)-2)
{
if (items_read)
break;
else
g_set_error_literal (error, G_CONVERT_ERROR, G_CONVERT_ERROR_PARTIAL_INPUT,
_("Partial character sequence at end of input"));
}
else
g_set_error_literal (error, G_CONVERT_ERROR, G_CONVERT_ERROR_ILLEGAL_SEQUENCE,
_("Invalid byte sequence in conversion input"));
goto err_out;
}
n_chars++;
in = g_utf8_next_char (in);
}
result = try_malloc_n (n_chars + 1, sizeof (gunichar), error);
if (result == NULL)
goto err_out;
in = str;
for (i=0; i < n_chars; i++)
{
result[i] = g_utf8_get_char (in);
in = g_utf8_next_char (in);
}
result[i] = 0;
if (items_written)
*items_written = n_chars;
err_out:
if (items_read)
*items_read = in - str;
return result;
}
/**
* g_ucs4_to_utf8:
* @str: (array length=len) (element-type gunichar): a UCS-4 encoded string
* @len: the maximum length (number of characters) of @str to use.
* If @len < 0, then the string is nul-terminated.
* @items_read: (out) (optional): location to store number of
* characters read, or %NULL.
* @items_written: (out) (optional): location to store number
* of bytes written or %NULL. The value here stored does not include the
* trailing 0 byte.
* @error: location to store the error occurring, or %NULL to ignore
* errors. Any of the errors in #GConvertError other than
* %G_CONVERT_ERROR_NO_CONVERSION may occur.
*
* Convert a string from a 32-bit fixed width representation as UCS-4.
* to UTF-8. The result will be terminated with a 0 byte.
*
* Returns: (transfer full): a pointer to a newly allocated UTF-8 string.
* This value must be freed with g_free(). If an error occurs,
* %NULL will be returned and @error set. In that case, @items_read
* will be set to the position of the first invalid input character.
*/
gchar *
g_ucs4_to_utf8 (const gunichar *str,
glong len,
glong *items_read,
glong *items_written,
GError **error)
{
gint result_length;
gchar *result = NULL;
gchar *p;
gint i;
result_length = 0;
for (i = 0; len < 0 || i < len ; i++)
{
if (!str[i])
break;
if (str[i] >= 0x80000000)
{
g_set_error_literal (error, G_CONVERT_ERROR, G_CONVERT_ERROR_ILLEGAL_SEQUENCE,
_("Character out of range for UTF-8"));
goto err_out;
}
result_length += UTF8_LENGTH (str[i]);
}
result = try_malloc_n (result_length + 1, 1, error);
if (result == NULL)
goto err_out;
p = result;
i = 0;
while (p < result + result_length)
p += g_unichar_to_utf8 (str[i++], p);
*p = '\0';
if (items_written)
*items_written = p - result;
err_out:
if (items_read)
*items_read = i;
return result;
}
#define SURROGATE_VALUE(h,l) (((h) - 0xd800) * 0x400 + (l) - 0xdc00 + 0x10000)
/**
* g_utf16_to_utf8:
* @str: (array length=len) (element-type guint16): a UTF-16 encoded string
* @len: the maximum length (number of #gunichar2) of @str to use.
* If @len < 0, then the string is nul-terminated.
* @items_read: (out) (optional): location to store number of
* words read, or %NULL. If %NULL, then %G_CONVERT_ERROR_PARTIAL_INPUT will
* be returned in case @str contains a trailing partial character. If
* an error occurs then the index of the invalid input is stored here.
* It’s guaranteed to be non-negative.
* @items_written: (out) (optional): location to store number
* of bytes written, or %NULL. The value stored here does not include the
* trailing 0 byte. It’s guaranteed to be non-negative.
* @error: location to store the error occurring, or %NULL to ignore
* errors. Any of the errors in #GConvertError other than
* %G_CONVERT_ERROR_NO_CONVERSION may occur.
*
* Convert a string from UTF-16 to UTF-8. The result will be
* terminated with a 0 byte.
*
* Note that the input is expected to be already in native endianness,
* an initial byte-order-mark character is not handled specially.
* g_convert() can be used to convert a byte buffer of UTF-16 data of
* ambiguous endianness.
*
* Further note that this function does not validate the result
* string; it may e.g. include embedded NUL characters. The only
* validation done by this function is to ensure that the input can
* be correctly interpreted as UTF-16, i.e. it doesn't contain
* unpaired surrogates or partial character sequences.
*
* Returns: (transfer full): a pointer to a newly allocated UTF-8 string.
* This value must be freed with g_free(). If an error occurs,
* %NULL will be returned and @error set.
**/
gchar *
g_utf16_to_utf8 (const gunichar2 *str,
glong len,
glong *items_read,
glong *items_written,
GError **error)
{
/* This function and g_utf16_to_ucs4 are almost exactly identical -
* The lines that differ are marked.
*/
const gunichar2 *in;
gchar *out;
gchar *result = NULL;
gint n_bytes;
gunichar high_surrogate;
g_return_val_if_fail (str != NULL, NULL);
n_bytes = 0;
in = str;
high_surrogate = 0;
while ((len < 0 || in - str < len) && *in)
{
gunichar2 c = *in;
gunichar wc;
if (c >= 0xdc00 && c < 0xe000) /* low surrogate */
{
if (high_surrogate)
{
wc = SURROGATE_VALUE (high_surrogate, c);
high_surrogate = 0;
}
else
{
g_set_error_literal (error, G_CONVERT_ERROR, G_CONVERT_ERROR_ILLEGAL_SEQUENCE,
_("Invalid sequence in conversion input"));
goto err_out;
}
}
else
{
if (high_surrogate)
{
g_set_error_literal (error, G_CONVERT_ERROR, G_CONVERT_ERROR_ILLEGAL_SEQUENCE,
_("Invalid sequence in conversion input"));
goto err_out;
}
if (c >= 0xd800 && c < 0xdc00) /* high surrogate */
{
high_surrogate = c;
goto next1;
}
else
wc = c;
}
/********** DIFFERENT for UTF8/UCS4 **********/
n_bytes += UTF8_LENGTH (wc);
next1:
in++;
}
if (high_surrogate && !items_read)
{
g_set_error_literal (error, G_CONVERT_ERROR, G_CONVERT_ERROR_PARTIAL_INPUT,
_("Partial character sequence at end of input"));
goto err_out;
}
/* At this point, everything is valid, and we just need to convert
*/
/********** DIFFERENT for UTF8/UCS4 **********/
result = try_malloc_n (n_bytes + 1, 1, error);
if (result == NULL)
goto err_out;
high_surrogate = 0;
out = result;
in = str;
while (out < result + n_bytes)
{
gunichar2 c = *in;
gunichar wc;
if (c >= 0xdc00 && c < 0xe000) /* low surrogate */
{
wc = SURROGATE_VALUE (high_surrogate, c);
high_surrogate = 0;
}
else if (c >= 0xd800 && c < 0xdc00) /* high surrogate */
{
high_surrogate = c;
goto next2;
}
else
wc = c;
/********** DIFFERENT for UTF8/UCS4 **********/
out += g_unichar_to_utf8 (wc, out);
next2:
in++;
}
/********** DIFFERENT for UTF8/UCS4 **********/
*out = '\0';
if (items_written)
/********** DIFFERENT for UTF8/UCS4 **********/
*items_written = out - result;
err_out:
if (items_read)
*items_read = in - str;
return result;
}
/**
* g_utf16_to_ucs4:
* @str: (array length=len) (element-type guint16): a UTF-16 encoded string
* @len: the maximum length (number of #gunichar2) of @str to use.
* If @len < 0, then the string is nul-terminated.
* @items_read: (out) (optional): location to store number of
* words read, or %NULL. If %NULL, then %G_CONVERT_ERROR_PARTIAL_INPUT will
* be returned in case @str contains a trailing partial character. If
* an error occurs then the index of the invalid input is stored here.
* @items_written: (out) (optional): location to store number
* of characters written, or %NULL. The value stored here does not include
* the trailing 0 character.
* @error: location to store the error occurring, or %NULL to ignore
* errors. Any of the errors in #GConvertError other than
* %G_CONVERT_ERROR_NO_CONVERSION may occur.
*
* Convert a string from UTF-16 to UCS-4. The result will be
* nul-terminated.
*
* Returns: (transfer full): a pointer to a newly allocated UCS-4 string.
* This value must be freed with g_free(). If an error occurs,
* %NULL will be returned and @error set.
*/
gunichar *
g_utf16_to_ucs4 (const gunichar2 *str,
glong len,
glong *items_read,
glong *items_written,
GError **error)
{
const gunichar2 *in;
gchar *out;
gchar *result = NULL;
gint n_bytes;
gunichar high_surrogate;
g_return_val_if_fail (str != NULL, NULL);
n_bytes = 0;
in = str;
high_surrogate = 0;
while ((len < 0 || in - str < len) && *in)
{
gunichar2 c = *in;
if (c >= 0xdc00 && c < 0xe000) /* low surrogate */
{
if (high_surrogate)
{
high_surrogate = 0;
}
else
{
g_set_error_literal (error, G_CONVERT_ERROR, G_CONVERT_ERROR_ILLEGAL_SEQUENCE,
_("Invalid sequence in conversion input"));
goto err_out;
}
}
else
{
if (high_surrogate)
{
g_set_error_literal (error, G_CONVERT_ERROR, G_CONVERT_ERROR_ILLEGAL_SEQUENCE,
_("Invalid sequence in conversion input"));
goto err_out;
}
if (c >= 0xd800 && c < 0xdc00) /* high surrogate */
{
high_surrogate = c;
goto next1;
}
}
/********** DIFFERENT for UTF8/UCS4 **********/
n_bytes += sizeof (gunichar);
next1:
in++;
}
if (high_surrogate && !items_read)
{
g_set_error_literal (error, G_CONVERT_ERROR, G_CONVERT_ERROR_PARTIAL_INPUT,
_("Partial character sequence at end of input"));
goto err_out;
}
/* At this point, everything is valid, and we just need to convert
*/
/********** DIFFERENT for UTF8/UCS4 **********/
result = try_malloc_n (n_bytes + 4, 1, error);
if (result == NULL)
goto err_out;
high_surrogate = 0;
out = result;
in = str;
while (out < result + n_bytes)
{
gunichar2 c = *in;
gunichar wc;
if (c >= 0xdc00 && c < 0xe000) /* low surrogate */
{
wc = SURROGATE_VALUE (high_surrogate, c);
high_surrogate = 0;
}
else if (c >= 0xd800 && c < 0xdc00) /* high surrogate */
{
high_surrogate = c;
goto next2;
}
else
wc = c;
/********** DIFFERENT for UTF8/UCS4 **********/
*(gunichar *)out = wc;
out += sizeof (gunichar);
next2:
in++;
}
/********** DIFFERENT for UTF8/UCS4 **********/
*(gunichar *)out = 0;
if (items_written)
/********** DIFFERENT for UTF8/UCS4 **********/
*items_written = (out - result) / sizeof (gunichar);
err_out:
if (items_read)
*items_read = in - str;
return (gunichar *)result;
}
/**
* g_utf8_to_utf16:
* @str: a UTF-8 encoded string
* @len: the maximum length (number of bytes) of @str to use.
* If @len < 0, then the string is nul-terminated.
* @items_read: (out) (optional): location to store number of
* bytes read, or %NULL. If %NULL, then %G_CONVERT_ERROR_PARTIAL_INPUT will
* be returned in case @str contains a trailing partial character. If
* an error occurs then the index of the invalid input is stored here.
* @items_written: (out) (optional): location to store number
* of #gunichar2 written, or %NULL. The value stored here does not include
* the trailing 0.
* @error: location to store the error occurring, or %NULL to ignore
* errors. Any of the errors in #GConvertError other than
* %G_CONVERT_ERROR_NO_CONVERSION may occur.
*
* Convert a string from UTF-8 to UTF-16. A 0 character will be
* added to the result after the converted text.
*
* Returns: (transfer full): a pointer to a newly allocated UTF-16 string.
* This value must be freed with g_free(). If an error occurs,
* %NULL will be returned and @error set.
*/
gunichar2 *
g_utf8_to_utf16 (const gchar *str,
glong len,
glong *items_read,
glong *items_written,
GError **error)
{
gunichar2 *result = NULL;
gint n16;
const gchar *in;
gint i;
g_return_val_if_fail (str != NULL, NULL);
in = str;
n16 = 0;
while ((len < 0 || str + len - in > 0) && *in)
{
gunichar wc = g_utf8_get_char_extended (in, len < 0 ? 6 : str + len - in);
if (wc & 0x80000000)
{
if (wc == (gunichar)-2)
{
if (items_read)
break;
else
g_set_error_literal (error, G_CONVERT_ERROR, G_CONVERT_ERROR_PARTIAL_INPUT,
_("Partial character sequence at end of input"));
}
else
g_set_error_literal (error, G_CONVERT_ERROR, G_CONVERT_ERROR_ILLEGAL_SEQUENCE,
_("Invalid byte sequence in conversion input"));
goto err_out;
}
if (wc < 0xd800)
n16 += 1;
else if (wc < 0xe000)
{
g_set_error_literal (error, G_CONVERT_ERROR, G_CONVERT_ERROR_ILLEGAL_SEQUENCE,
_("Invalid sequence in conversion input"));
goto err_out;
}
else if (wc < 0x10000)
n16 += 1;
else if (wc < 0x110000)
n16 += 2;
else
{
g_set_error_literal (error, G_CONVERT_ERROR, G_CONVERT_ERROR_ILLEGAL_SEQUENCE,
_("Character out of range for UTF-16"));
goto err_out;
}
in = g_utf8_next_char (in);
}
result = try_malloc_n (n16 + 1, sizeof (gunichar2), error);
if (result == NULL)
goto err_out;
in = str;
for (i = 0; i < n16;)
{
gunichar wc = g_utf8_get_char (in);
if (wc < 0x10000)
{
result[i++] = wc;
}
else
{
result[i++] = (wc - 0x10000) / 0x400 + 0xd800;
result[i++] = (wc - 0x10000) % 0x400 + 0xdc00;
}
in = g_utf8_next_char (in);
}
result[i] = 0;
if (items_written)
*items_written = n16;
err_out:
if (items_read)
*items_read = in - str;
return result;
}
/**
* g_ucs4_to_utf16:
* @str: (array length=len) (element-type gunichar): a UCS-4 encoded string
* @len: the maximum length (number of characters) of @str to use.
* If @len < 0, then the string is nul-terminated.
* @items_read: (out) (optional): location to store number of
* bytes read, or %NULL. If an error occurs then the index of the invalid
* input is stored here.
* @items_written: (out) (optional): location to store number
* of #gunichar2 written, or %NULL. The value stored here does not include
* the trailing 0.
* @error: location to store the error occurring, or %NULL to ignore
* errors. Any of the errors in #GConvertError other than
* %G_CONVERT_ERROR_NO_CONVERSION may occur.
*
* Convert a string from UCS-4 to UTF-16. A 0 character will be
* added to the result after the converted text.
*
* Returns: (transfer full): a pointer to a newly allocated UTF-16 string.
* This value must be freed with g_free(). If an error occurs,
* %NULL will be returned and @error set.
*/
gunichar2 *
g_ucs4_to_utf16 (const gunichar *str,
glong len,
glong *items_read,
glong *items_written,
GError **error)
{
gunichar2 *result = NULL;
gint n16;
gint i, j;
n16 = 0;
i = 0;
while ((len < 0 || i < len) && str[i])
{
gunichar wc = str[i];
if (wc < 0xd800)
n16 += 1;
else if (wc < 0xe000)
{
g_set_error_literal (error, G_CONVERT_ERROR, G_CONVERT_ERROR_ILLEGAL_SEQUENCE,
_("Invalid sequence in conversion input"));
goto err_out;
}
else if (wc < 0x10000)
n16 += 1;
else if (wc < 0x110000)
n16 += 2;
else
{
g_set_error_literal (error, G_CONVERT_ERROR, G_CONVERT_ERROR_ILLEGAL_SEQUENCE,
_("Character out of range for UTF-16"));
goto err_out;
}
i++;
}
result = try_malloc_n (n16 + 1, sizeof (gunichar2), error);
if (result == NULL)
goto err_out;
for (i = 0, j = 0; j < n16; i++)
{
gunichar wc = str[i];
if (wc < 0x10000)
{
result[j++] = wc;
}
else
{
result[j++] = (wc - 0x10000) / 0x400 + 0xd800;
result[j++] = (wc - 0x10000) % 0x400 + 0xdc00;
}
}
result[j] = 0;
if (items_written)
*items_written = n16;
err_out:
if (items_read)
*items_read = i;
return result;
}
#define VALIDATE_BYTE(mask, expect) \
G_STMT_START { \
if (G_UNLIKELY((*(guchar *)p & (mask)) != (expect))) \
goto error; \
} G_STMT_END
/* see IETF RFC 3629 Section 4 */
static const gchar *
fast_validate (const char *str)
{
const gchar *p;
for (p = str; *p; p++)
{
if (*(guchar *)p < 128)
/* done */;
else
{
const gchar *last;
last = p;
if (*(guchar *)p < 0xe0) /* 110xxxxx */
{
if (G_UNLIKELY (*(guchar *)p < 0xc2))
goto error;
}
else
{
if (*(guchar *)p < 0xf0) /* 1110xxxx */
{
switch (*(guchar *)p++ & 0x0f)
{
case 0:
VALIDATE_BYTE(0xe0, 0xa0); /* 0xa0 ... 0xbf */
break;
case 0x0d:
VALIDATE_BYTE(0xe0, 0x80); /* 0x80 ... 0x9f */
break;
default:
VALIDATE_BYTE(0xc0, 0x80); /* 10xxxxxx */
}
}
else if (*(guchar *)p < 0xf5) /* 11110xxx excluding out-of-range */
{
switch (*(guchar *)p++ & 0x07)
{
case 0:
VALIDATE_BYTE(0xc0, 0x80); /* 10xxxxxx */
if (G_UNLIKELY((*(guchar *)p & 0x30) == 0))
goto error;
break;
case 4:
VALIDATE_BYTE(0xf0, 0x80); /* 0x80 ... 0x8f */
break;
default:
VALIDATE_BYTE(0xc0, 0x80); /* 10xxxxxx */
}
p++;
VALIDATE_BYTE(0xc0, 0x80); /* 10xxxxxx */
}
else
goto error;
}
p++;
VALIDATE_BYTE(0xc0, 0x80); /* 10xxxxxx */
continue;
error:
return last;
}
}
return p;
}
static const gchar *
fast_validate_len (const char *str,
gssize max_len)
{
const gchar *p;
g_assert (max_len >= 0);
for (p = str; ((p - str) < max_len) && *p; p++)
{
if (*(guchar *)p < 128)
/* done */;
else
{
const gchar *last;
last = p;
if (*(guchar *)p < 0xe0) /* 110xxxxx */
{
if (G_UNLIKELY (max_len - (p - str) < 2))
goto error;
if (G_UNLIKELY (*(guchar *)p < 0xc2))
goto error;
}
else
{
if (*(guchar *)p < 0xf0) /* 1110xxxx */
{
if (G_UNLIKELY (max_len - (p - str) < 3))
goto error;
switch (*(guchar *)p++ & 0x0f)
{
case 0:
VALIDATE_BYTE(0xe0, 0xa0); /* 0xa0 ... 0xbf */
break;
case 0x0d:
VALIDATE_BYTE(0xe0, 0x80); /* 0x80 ... 0x9f */
break;
default:
VALIDATE_BYTE(0xc0, 0x80); /* 10xxxxxx */
}
}
else if (*(guchar *)p < 0xf5) /* 11110xxx excluding out-of-range */
{
if (G_UNLIKELY (max_len - (p - str) < 4))
goto error;
switch (*(guchar *)p++ & 0x07)
{
case 0:
VALIDATE_BYTE(0xc0, 0x80); /* 10xxxxxx */
if (G_UNLIKELY((*(guchar *)p & 0x30) == 0))
goto error;
break;
case 4:
VALIDATE_BYTE(0xf0, 0x80); /* 0x80 ... 0x8f */
break;
default:
VALIDATE_BYTE(0xc0, 0x80); /* 10xxxxxx */
}
p++;
VALIDATE_BYTE(0xc0, 0x80); /* 10xxxxxx */
}
else
goto error;
}
p++;
VALIDATE_BYTE(0xc0, 0x80); /* 10xxxxxx */
continue;
error:
return last;
}
}
return p;
}
/**
* g_utf8_validate:
* @str: (array length=max_len) (element-type guint8): a pointer to character data
* @max_len: max bytes to validate, or -1 to go until NUL
* @end: (out) (optional) (transfer none): return location for end of valid data
*
* Validates UTF-8 encoded text. @str is the text to validate;
* if @str is nul-terminated, then @max_len can be -1, otherwise
* @max_len should be the number of bytes to validate.
* If @end is non-%NULL, then the end of the valid range
* will be stored there (i.e. the start of the first invalid
* character if some bytes were invalid, or the end of the text
* being validated otherwise).
*
* Note that g_utf8_validate() returns %FALSE if @max_len is
* positive and any of the @max_len bytes are nul.
*
* Returns %TRUE if all of @str was valid. Many GLib and GTK
* routines require valid UTF-8 as input; so data read from a file
* or the network should be checked with g_utf8_validate() before
* doing anything else with it.
*
* Returns: %TRUE if the text was valid UTF-8
*/
gboolean
g_utf8_validate (const char *str,
gssize max_len,
const gchar **end)
{
const gchar *p;
if (max_len >= 0)
return g_utf8_validate_len (str, max_len, end);
p = fast_validate (str);
if (end)
*end = p;
if (*p != '\0')
return FALSE;
else
return TRUE;
}
/**
* g_utf8_validate_len:
* @str: (array length=max_len) (element-type guint8): a pointer to character data
* @max_len: max bytes to validate
* @end: (out) (optional) (transfer none): return location for end of valid data
*
* Validates UTF-8 encoded text.
*
* As with g_utf8_validate(), but @max_len must be set, and hence this function
* will always return %FALSE if any of the bytes of @str are nul.
*
* Returns: %TRUE if the text was valid UTF-8
* Since: 2.60
*/
gboolean
g_utf8_validate_len (const char *str,
gsize max_len,
const gchar **end)
{
const gchar *p;
p = fast_validate_len (str, max_len);
if (end)
*end = p;
if (p != str + max_len)
return FALSE;
else
return TRUE;
}
/**
* g_unichar_validate:
* @ch: a Unicode character
*
* Checks whether @ch is a valid Unicode character. Some possible
* integer values of @ch will not be valid. 0 is considered a valid
* character, though it's normally a string terminator.
*
* Returns: %TRUE if @ch is a valid Unicode character
**/
gboolean
g_unichar_validate (gunichar ch)
{
return UNICODE_VALID (ch);
}
/**
* g_utf8_strreverse:
* @str: a UTF-8 encoded string
* @len: the maximum length of @str to use, in bytes. If @len < 0,
* then the string is nul-terminated.
*
* Reverses a UTF-8 string. @str must be valid UTF-8 encoded text.
* (Use g_utf8_validate() on all text before trying to use UTF-8
* utility functions with it.)
*
* This function is intended for programmatic uses of reversed strings.
* It pays no attention to decomposed characters, combining marks, byte
* order marks, directional indicators (LRM, LRO, etc) and similar
* characters which might need special handling when reversing a string
* for display purposes.
*
* Note that unlike g_strreverse(), this function returns
* newly-allocated memory, which should be freed with g_free() when
* no longer needed.
*
* Returns: (transfer full): a newly-allocated string which is the reverse of @str
*
* Since: 2.2
*/
gchar *
g_utf8_strreverse (const gchar *str,
gssize len)
{
gchar *r, *result;
const gchar *p;
if (len < 0)
len = strlen (str);
result = g_new (gchar, len + 1);
r = result + len;
p = str;
while (r > result)
{
gchar *m, skip = g_utf8_skip[*(guchar*) p];
r -= skip;
g_assert (r >= result);
for (m = r; skip; skip--)
*m++ = *p++;
}
result[len] = 0;
return result;
}
/**
* g_utf8_make_valid:
* @str: string to coerce into UTF-8
* @len: the maximum length of @str to use, in bytes. If @len < 0,
* then the string is nul-terminated.
*
* If the provided string is valid UTF-8, return a copy of it. If not,
* return a copy in which bytes that could not be interpreted as valid Unicode
* are replaced with the Unicode replacement character (U+FFFD).
*
* For example, this is an appropriate function to use if you have received
* a string that was incorrectly declared to be UTF-8, and you need a valid
* UTF-8 version of it that can be logged or displayed to the user, with the
* assumption that it is close enough to ASCII or UTF-8 to be mostly
* readable as-is.
*
* Returns: (transfer full): a valid UTF-8 string whose content resembles @str
*
* Since: 2.52
*/
gchar *
g_utf8_make_valid (const gchar *str,
gssize len)
{
GString *string;
const gchar *remainder, *invalid;
gsize remaining_bytes, valid_bytes;
g_return_val_if_fail (str != NULL, NULL);
if (len < 0)
len = strlen (str);
string = NULL;
remainder = str;
remaining_bytes = len;
while (remaining_bytes != 0)
{
if (g_utf8_validate (remainder, remaining_bytes, &invalid))
break;
valid_bytes = invalid - remainder;
if (string == NULL)
string = g_string_sized_new (remaining_bytes);
g_string_append_len (string, remainder, valid_bytes);
/* append U+FFFD REPLACEMENT CHARACTER */
g_string_append (string, "\357\277\275");
remaining_bytes -= valid_bytes + 1;
remainder = invalid + 1;
}
if (string == NULL)
return g_strndup (str, len);
g_string_append_len (string, remainder, remaining_bytes);
g_string_append_c (string, '\0');
g_assert (g_utf8_validate (string->str, -1, NULL));
return g_string_free (string, FALSE);
}
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