glib/glib/gutf8.c
Matthias Clasen 9eb65dd3ed Unicode: add a g_utf8_substring convenience api
This function is useful in the GTK+ accessibility implementations,
and seems like a nice thing to have around in general.
2011-06-23 21:31:40 -04:00

1919 lines
47 KiB
C

/* gutf8.c - Operations on UTF-8 strings.
*
* Copyright (C) 1999 Tom Tromey
* Copyright (C) 2000 Red Hat, Inc.
*
* 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 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, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
#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 "libcharset/libcharset.h"
#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).
*
* The last two checks cover "Noncharacter": defined as:
* "A code point that is permanently reserved for
* internal use, and that should never be interchanged. In
* Unicode 3.1, these consist of the values U+nFFFE and U+nFFFF
* (where n is from 0 to 10_16) and the values U+FDD0..U+FDEF."
*
* @param Char the character
*/
#define UNICODE_VALID(Char) \
((Char) < 0x110000 && \
(((Char) & 0xFFFFF800) != 0xD800) && \
((Char) < 0xFDD0 || (Char) > 0xFDEF) && \
((Char) & 0xFFFE) != 0xFFFE)
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.
*
* Return value: a pointer to the found character or %NULL.
**/
gchar *
g_utf8_find_prev_char (const char *str,
const char *p)
{
for (--p; 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: 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.
*
* Return value: a pointer to the found character or %NULL
**/
gchar *
g_utf8_find_next_char (const gchar *p,
const gchar *end)
{
if (*p)
{
if (end)
for (++p; p < end && (*p & 0xc0) == 0x80; ++p)
;
else
for (++p; (*p & 0xc0) == 0x80; ++p)
;
}
return (p == end) ? NULL : (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.
*
* Return value: 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.
*
* Computes the length of the string in characters, not including
* the terminating nul character.
*
* Return value: 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
*
* Copies a substring out of a UTF-8 encoded string.
* The substring will contain @end_pos - @start_pos
* characters.
*
* Returns: 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;
start = g_utf8_offset_to_pointer (str, start_pos);
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.
*
* Return value: 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><para>
* 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.
* </para></note>
*
* Return value: 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 a integer
* character offset.
*
* Since 2.10, this function allows @pos to be before @str, and returns
* a negative offset in this case.
*
* Return value: 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: 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.)
*
* Return value: @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_LOCK_DEFINE_STATIC (aliases);
static GHashTable *
get_alias_hash (void)
{
static GHashTable *alias_hash = NULL;
const char *aliases;
G_LOCK (aliases);
if (!alias_hash)
{
alias_hash = g_hash_table_new (g_str_hash, g_str_equal);
aliases = _g_locale_get_charset_aliases ();
while (*aliases != '\0')
{
const char *canonical;
const char *alias;
const char **alias_array;
int count = 0;
alias = aliases;
aliases += strlen (aliases) + 1;
canonical = aliases;
aliases += strlen (aliases) + 1;
alias_array = g_hash_table_lookup (alias_hash, canonical);
if (alias_array)
{
while (alias_array[count])
count++;
}
alias_array = g_renew (const char *, alias_array, count + 2);
alias_array[count] = alias;
alias_array[count + 1] = NULL;
g_hash_table_insert (alias_hash, (char *)canonical, alias_array);
}
}
G_UNLOCK (aliases);
return alias_hash;
}
/* As an abuse of the alias table, the following routines gets
* the charsets that are aliases for the canonical name.
*/
G_GNUC_INTERNAL const char **
_g_charset_get_aliases (const char *canonical_name)
{
GHashTable *alias_hash = get_alias_hash ();
return g_hash_table_lookup (alias_hash, canonical_name);
}
static gboolean
g_utf8_get_charset_internal (const char *raw_data,
const char **a)
{
const char *charset = getenv("CHARSET");
if (charset && *charset)
{
*a = charset;
if (charset && strstr (charset, "UTF-8"))
return TRUE;
else
return FALSE;
}
/* The libcharset code tries to be thread-safe without
* a lock, but has a memory leak and a missing memory
* barrier, so we lock for it
*/
G_LOCK (aliases);
charset = _g_locale_charset_unalias (raw_data);
G_UNLOCK (aliases);
if (charset && *charset)
{
*a = charset;
if (charset && strstr (charset, "UTF-8"))
return TRUE;
else
return FALSE;
}
/* Assume this for compatibility at present. */
*a = "US-ASCII";
return FALSE;
}
typedef struct _GCharsetCache GCharsetCache;
struct _GCharsetCache {
gboolean is_utf8;
gchar *raw;
gchar *charset;
};
static void
charset_cache_free (gpointer data)
{
GCharsetCache *cache = data;
g_free (cache->raw);
g_free (cache->charset);
g_free (cache);
}
/**
* g_get_charset:
* @charset: return location for character set name
*
* Obtains the character set for the <link linkend="setlocale">current
* locale</link>; you might use this character set as an argument to
* g_convert(), to convert from the current locale's encoding to some
* other encoding. (Frequently g_locale_to_utf8() and g_locale_from_utf8()
* are nice shortcuts, though.)
*
* On Windows the character set returned by this function is the
* so-called system default ANSI code-page. That is the character set
* used by the "narrow" versions of C library and Win32 functions that
* handle file names. It might be different from the character set
* used by the C library's current locale.
*
* The return value is %TRUE if the locale's encoding is UTF-8, in that
* case you can perhaps avoid calling g_convert().
*
* The string returned in @charset is not allocated, and should not be
* freed.
*
* Return value: %TRUE if the returned charset is UTF-8
**/
gboolean
g_get_charset (const char **charset)
{
static GStaticPrivate cache_private = G_STATIC_PRIVATE_INIT;
GCharsetCache *cache = g_static_private_get (&cache_private);
const gchar *raw;
if (!cache)
{
cache = g_new0 (GCharsetCache, 1);
g_static_private_set (&cache_private, cache, charset_cache_free);
}
raw = _g_locale_charset_raw ();
if (!(cache->raw && strcmp (cache->raw, raw) == 0))
{
const gchar *new_charset;
g_free (cache->raw);
g_free (cache->charset);
cache->raw = g_strdup (raw);
cache->is_utf8 = g_utf8_get_charset_internal (raw, &new_charset);
cache->charset = g_strdup (new_charset);
}
if (charset)
*charset = cache->charset;
return cache->is_utf8;
}
/* unicode_strchr */
/**
* g_unichar_to_utf8:
* @c: a Unicode character code
* @outbuf: 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.
*
* Return value: 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.
*
* Return value: %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.
*
* Return value: %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)
{
guint i, len;
gunichar min_code;
gunichar wc = (guchar) *p;
if (wc < 0x80)
{
return wc;
}
else if (G_UNLIKELY (wc < 0xc0))
{
return (gunichar)-1;
}
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 (gunichar)-1;
}
if (G_UNLIKELY (max_len >= 0 && len > max_len))
{
for (i = 1; i < max_len; i++)
{
if ((((guchar *)p)[i] & 0xc0) != 0x80)
return (gunichar)-1;
}
return (gunichar)-2;
}
for (i = 1; i < len; ++i)
{
gunichar ch = ((guchar *)p)[i];
if (G_UNLIKELY ((ch & 0xc0) != 0x80))
{
if (ch)
return (gunichar)-1;
else
return (gunichar)-2;
}
wc <<= 6;
wc |= (ch & 0x3f);
}
if (G_UNLIKELY (wc < min_code))
return (gunichar)-1;
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, for no maximum or
* 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.
*
* Return value: 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);
if (result & 0x80000000)
return result;
else if (!UNICODE_VALID (result))
return (gunichar)-1;
else
return result;
}
/**
* 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: 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.
*
* Return value: 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++)
{
gunichar wc = (guchar)*p++;
if (wc < 0x80)
{
result[i] = wc;
}
else
{
gunichar mask = 0x40;
if (G_UNLIKELY ((wc & mask) == 0))
{
/* It's an out-of-sequence 10xxxxxxx byte.
* Rather than making an ugly hash of this and the next byte
* and overrunning the buffer, it's more useful to treat it
* with a replacement character */
result[i] = 0xfffd;
continue;
}
do
{
wc <<= 6;
wc |= (guchar)(*p++) & 0x3f;
mask <<= 5;
}
while((wc & mask) != 0);
wc &= mask - 1;
result[i] = wc;
}
}
result[i] = 0;
if (items_written)
*items_written = i;
return result;
}
/**
* 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: 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: 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 occuring, 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.
*
* Return value: 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 = g_new (gunichar, n_chars + 1);
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: 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: location to store number of characters read, or %NULL.
* @items_written: 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 occuring, 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.
*
* Return value: 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 = g_malloc (result_length + 1);
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: a UTF-16 encoded string
* @len: the maximum length (number of <type>gunichar2</type>) of @str to use.
* If @len < 0, then the string is nul-terminated.
* @items_read: 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: location to store number of bytes written, or %NULL.
* The value stored here does not include the trailing
* 0 byte.
* @error: location to store the error occuring, 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 endianess.
*
* 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
* things unpaired surrogates.
*
* Return value: 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 = g_malloc (n_bytes + 1);
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: a UTF-16 encoded string
* @len: the maximum length (number of <type>gunichar2</type>) of @str to use.
* If @len < 0, then the string is nul-terminated.
* @items_read: 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: 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 occuring, 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.
*
* Return value: 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 = g_malloc (n_bytes + 4);
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: 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: location to store number of <type>gunichar2</type> written,
* or %NULL.
* The value stored here does not include the trailing 0.
* @error: location to store the error occuring, 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.
*
* Return value: 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 = g_new (gunichar2, n16 + 1);
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: 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: 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: location to store number of <type>gunichar2</type>
* written, or %NULL. The value stored here does not
* include the trailing 0.
* @error: location to store the error occuring, 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.
*
* Return value: 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 = g_new (gunichar2, n16 + 1);
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 CONTINUATION_CHAR \
G_STMT_START { \
if ((*(guchar *)p & 0xc0) != 0x80) /* 10xxxxxx */ \
goto error; \
val <<= 6; \
val |= (*(guchar *)p) & 0x3f; \
} G_STMT_END
static const gchar *
fast_validate (const char *str)
{
gunichar val = 0;
gunichar min = 0;
const gchar *p;
for (p = str; *p; p++)
{
if (*(guchar *)p < 128)
/* done */;
else
{
const gchar *last;
last = p;
if ((*(guchar *)p & 0xe0) == 0xc0) /* 110xxxxx */
{
if (G_UNLIKELY ((*(guchar *)p & 0x1e) == 0))
goto error;
p++;
if (G_UNLIKELY ((*(guchar *)p & 0xc0) != 0x80)) /* 10xxxxxx */
goto error;
}
else
{
if ((*(guchar *)p & 0xf0) == 0xe0) /* 1110xxxx */
{
min = (1 << 11);
val = *(guchar *)p & 0x0f;
goto TWO_REMAINING;
}
else if ((*(guchar *)p & 0xf8) == 0xf0) /* 11110xxx */
{
min = (1 << 16);
val = *(guchar *)p & 0x07;
}
else
goto error;
p++;
CONTINUATION_CHAR;
TWO_REMAINING:
p++;
CONTINUATION_CHAR;
p++;
CONTINUATION_CHAR;
if (G_UNLIKELY (val < min))
goto error;
if (G_UNLIKELY (!UNICODE_VALID(val)))
goto error;
}
continue;
error:
return last;
}
}
return p;
}
static const gchar *
fast_validate_len (const char *str,
gssize max_len)
{
gunichar val = 0;
gunichar min = 0;
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) == 0xc0) /* 110xxxxx */
{
if (G_UNLIKELY (max_len - (p - str) < 2))
goto error;
if (G_UNLIKELY ((*(guchar *)p & 0x1e) == 0))
goto error;
p++;
if (G_UNLIKELY ((*(guchar *)p & 0xc0) != 0x80)) /* 10xxxxxx */
goto error;
}
else
{
if ((*(guchar *)p & 0xf0) == 0xe0) /* 1110xxxx */
{
if (G_UNLIKELY (max_len - (p - str) < 3))
goto error;
min = (1 << 11);
val = *(guchar *)p & 0x0f;
goto TWO_REMAINING;
}
else if ((*(guchar *)p & 0xf8) == 0xf0) /* 11110xxx */
{
if (G_UNLIKELY (max_len - (p - str) < 4))
goto error;
min = (1 << 16);
val = *(guchar *)p & 0x07;
}
else
goto error;
p++;
CONTINUATION_CHAR;
TWO_REMAINING:
p++;
CONTINUATION_CHAR;
p++;
CONTINUATION_CHAR;
if (G_UNLIKELY (val < min))
goto error;
if (G_UNLIKELY (!UNICODE_VALID(val)))
goto error;
}
continue;
error:
return last;
}
}
return p;
}
/**
* g_utf8_validate:
* @str: a pointer to character data
* @max_len: max bytes to validate, or -1 to go until NUL
* @end: 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 NUL is met before @max_len bytes have been read.
*
* Returns %TRUE if all of @str was valid. Many GLib and GTK+
* routines <emphasis>require</emphasis> 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.
*
* Return value: %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)
p = fast_validate (str);
else
p = fast_validate_len (str, max_len);
if (end)
*end = p;
if ((max_len >= 0 && p != str + max_len) ||
(max_len < 0 && *p != '\0'))
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.
*
* Return value: %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: 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;
for (m = r; skip; skip--)
*m++ = *p++;
}
result[len] = 0;
return result;
}
gchar *
_g_utf8_make_valid (const gchar *name)
{
GString *string;
const gchar *remainder, *invalid;
gint remaining_bytes, valid_bytes;
g_return_val_if_fail (name != NULL, NULL);
string = NULL;
remainder = name;
remaining_bytes = strlen (name);
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_strdup (name);
g_string_append (string, remainder);
g_assert (g_utf8_validate (string->str, -1, NULL));
return g_string_free (string, FALSE);
}