| /* 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> |
| |
| #include "glib.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_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); \ |
| } |
| gchar g_utf8_skip[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, |
| 3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,3,4,4,4,4,4,4,4,4,5,5,5,5,6,6,0,0 |
| }; |
| |
| /** |
| * g_utf8_find_prev_char: |
| * @str: pointer to the beginning of a UTF-8 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 @p before @str. |
| * |
| * @p does not have to be at the beginning of a UTF-8 chracter. 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 end of the string, or %NULL to indicate |
| * that the string is NULL terminated, in which case |
| * the returned value will be |
| * |
| * Find 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 chracter. 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 |
| * |
| * Find 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 string. |
| * @max: the maximum number of bytes to examine. If @max |
| * is less than 0, then the string is assumed to be |
| * nul-terminated. |
| * |
| * Return value: the length of the string in characters |
| */ |
| gint |
| g_utf8_strlen (const gchar *p, gint max) |
| { |
| int len = 0; |
| const gchar *start = p; |
| /* special case for the empty string */ |
| if (!*p) |
| return 0; |
| /* Note that the test here and the test in the loop differ subtly. |
| In the loop we want to see if we've passed the maximum limit -- |
| for instance if the buffer ends mid-character. Here at the top |
| of the loop we want to see if we've just reached the last byte. */ |
| while (max < 0 || p - start < max) |
| { |
| p = g_utf8_next_char (p); |
| ++len; |
| if (! *p || (max > 0 && p - start > max)) |
| break; |
| } |
| return len; |
| } |
| |
| /** |
| * g_utf8_get_char: |
| * @p: a pointer to unicode character encoded as UTF-8 |
| * |
| * Convert a sequence of bytes encoded as UTF-8 to a unicode character. |
| * |
| * Return value: the resulting character or (gunichar)-1 if @p does |
| * not point to a valid UTF-8 encoded unicode 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 the string. |
| * |
| * Converts from an integer character offset to a pointer to a position |
| * within the string. |
| * |
| * Return value: the resulting pointer |
| **/ |
| gchar * |
| g_utf8_offset_to_pointer (const gchar *str, |
| gint offset) |
| { |
| const gchar *s = str; |
| while (offset--) |
| s = g_utf8_next_char (s); |
| |
| 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 |
| * |
| * Return value: the resulting character offset |
| **/ |
| gint |
| g_utf8_pointer_to_offset (const gchar *str, |
| const gchar *pos) |
| { |
| const gchar *s = str; |
| gint offset = 0; |
| |
| while (s < pos) |
| { |
| s = g_utf8_next_char (s); |
| offset++; |
| } |
| |
| return offset; |
| } |
| |
| |
| gchar * |
| g_utf8_strncpy (gchar *dest, const gchar *src, size_t 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; |
| } |
| |
| static gboolean |
| g_utf8_get_charset_internal (char **a) |
| { |
| char *charset = getenv("CHARSET"); |
| |
| if (charset && a && ! *a) |
| *a = charset; |
| |
| if (charset && strstr (charset, "UTF-8")) |
| return TRUE; |
| |
| #ifdef HAVE_CODESET |
| charset = nl_langinfo(CODESET); |
| if (charset) |
| { |
| if (a && ! *a) |
| *a = charset; |
| if (strcmp (charset, "UTF-8") == 0) |
| return TRUE; |
| } |
| #endif |
| |
| #if 0 /* #ifdef _NL_CTYPE_CODESET_NAME */ |
| charset = nl_langinfo (_NL_CTYPE_CODESET_NAME); |
| if (charset) |
| { |
| if (a && ! *a) |
| *a = charset; |
| if (strcmp (charset, "UTF-8") == 0) |
| return TRUE; |
| } |
| #endif |
| |
| if (a && ! *a) |
| *a = "US-ASCII"; |
| /* Assume this for compatibility at present. */ |
| return FALSE; |
| } |
| |
| static int utf8_locale_cache = -1; |
| static char *utf8_charset_cache = NULL; |
| |
| gboolean |
| g_get_charset (char **charset) |
| { |
| if (utf8_locale_cache != -1) |
| { |
| if (charset) |
| *charset = utf8_charset_cache; |
| return utf8_locale_cache; |
| } |
| utf8_locale_cache = g_utf8_get_charset_internal (&utf8_charset_cache); |
| if (charset) |
| *charset = utf8_charset_cache; |
| return utf8_locale_cache; |
| } |
| |
| /* unicode_strchr */ |
| |
| /** |
| * g_unichar_to_utf8: |
| * @c: a ISO10646 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 @out. |
| * |
| * Convert a single character to utf8 |
| * |
| * Return value: number of bytes written |
| **/ |
| int |
| g_unichar_to_utf8 (gunichar c, gchar *outbuf) |
| { |
| size_t 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 string |
| * @c: a iso-10646 character/ |
| * |
| * Find the leftmost occurence of the given iso-10646 character |
| * in a UTF-8 string. |
| * |
| * Return value: NULL if the string does not contain the character, otherwise, a |
| * a pointer to the start of the leftmost of the character in the string. |
| **/ |
| gchar * |
| g_utf8_strchr (const char *p, gunichar c) |
| { |
| gchar ch[10]; |
| |
| gint len = g_unichar_to_utf8 (c, ch); |
| ch[len] = '\0'; |
| |
| return strstr(p, ch); |
| } |
| |
| #if 0 |
| /** |
| * g_utf8_strrchr: |
| * @p: a nul-terminated utf-8 string |
| * @c: a iso-10646 character/ |
| * |
| * Find the rightmost occurence of the given iso-10646 character |
| * in a UTF-8 string. |
| * |
| * Return value: NULL if the string does not contain the character, otherwise, a |
| * a pointer to the start of the rightmost of the character in the string. |
| **/ |
| |
| /* This is ifdefed out atm as there is no strrstr function in libc. |
| */ |
| gchar * |
| unicode_strrchr (const char *p, gunichar c) |
| { |
| gchar ch[10]; |
| |
| len = g_unichar_to_utf8 (c, ch); |
| ch[len] = '\0'; |
| |
| return strrstr(p, ch); |
| } |
| #endif |
| |
| |
| /** |
| * g_utf8_to_ucs4: |
| * @str: a UTF-8 encoded strnig |
| * @len: the length of @ |
| * |
| * Convert a string from UTF-8 to a 32-bit fixed width |
| * representation as UCS-4. |
| * |
| * Return value: a pointer to a newly allocated UCS-4 string. |
| * This value must be freed with g_free() |
| **/ |
| gunichar * |
| g_utf8_to_ucs4 (const char *str, int len) |
| { |
| gunichar *result; |
| gint n_chars, i; |
| const gchar *p; |
| |
| n_chars = g_utf8_strlen (str, len); |
| result = g_new (gunichar, n_chars); |
| |
| p = str; |
| for (i=0; i < n_chars; i++) |
| { |
| result[i] = g_utf8_get_char (p); |
| p = g_utf8_next_char (p); |
| } |
| |
| return result; |
| } |
| |
| /** |
| * g_ucs4_to_utf8: |
| * @str: a UCS-4 encoded string |
| * @len: the length of @ |
| * |
| * Convert a string from a 32-bit fixed width representation as UCS-4. |
| * to UTF-8. |
| * |
| * Return value: a pointer to a newly allocated UTF-8 string. |
| * This value must be freed with g_free() |
| **/ |
| gchar * |
| g_ucs4_to_utf8 (const gunichar *str, int len) |
| { |
| gint result_length; |
| gchar *result, *p; |
| gint i; |
| |
| result_length = 0; |
| for (i = 0; i < len ; i++) |
| result_length += g_unichar_to_utf8 (str[i], NULL); |
| |
| result_length++; |
| |
| result = g_malloc (result_length + 1); |
| p = result; |
| |
| for (i = 0; i < len ; i++) |
| p += g_unichar_to_utf8 (str[i], p); |
| |
| *p = '\0'; |
| |
| return result; |
| } |
| |
| /** |
| * 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 address of the first invalid byte |
| * if some bytes were invalid, or the end of the text being validated |
| * otherwise). |
| * |
| * Returns TRUE if all of @str was valid. Many GLib and GTK+ |
| * routines <emphasis>require</emphasis> valid UTF8 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 gchar *str, |
| gint max_len, |
| const gchar **end) |
| { |
| |
| const gchar *p; |
| gboolean retval = TRUE; |
| |
| if (end) |
| *end = str; |
| |
| p = str; |
| |
| while ((max_len < 0 || (p - str) < max_len) && *p) |
| { |
| int i, mask = 0, len; |
| gunichar result; |
| unsigned char c = (unsigned char) *p; |
| |
| UTF8_COMPUTE (c, mask, len); |
| |
| if (len == -1) |
| { |
| retval = FALSE; |
| break; |
| } |
| |
| /* check that the expected number of bytes exists in str */ |
| if (max_len >= 0 && |
| ((max_len - (p - str)) < len)) |
| { |
| retval = FALSE; |
| break; |
| } |
| |
| UTF8_GET (result, p, i, mask, len); |
| |
| if (result == (gunichar)-1) |
| { |
| retval = FALSE; |
| break; |
| } |
| |
| p += len; |
| } |
| |
| if (end) |
| *end = p; |
| |
| return retval; |
| } |
| |
| |