glib/gunidecomp.c - third_party/glib - Git at Google

 /* decomp.c - Character decomposition.
  *
  *  Copyright (C) 1999, 2000 Tom Tromey
  *  Copyright 2000 Red Hat, Inc.
  *
  * The Gnome 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.
  *
  * The Gnome 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 the Gnome Library; see the file COPYING.LIB.  If not,
  * write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  *   Boston, MA 02111-1307, USA.
  */

 #include "glib.h"
 #include "gunidecomp.h"
 #include "gunicomp.h"

 #include <config.h>

 #include <stdlib.h>

 #define CC(Page, Char) \
   ((combining_class_table[Page] >= G_UNICODE_MAX_TABLE_INDEX) \
    ? (combining_class_table[Page] - G_UNICODE_MAX_TABLE_INDEX) \
    : (cclass_data[combining_class_table[Page]][Char]))

 #define COMBINING_CLASS(Char) \
      (((Char) > (G_UNICODE_LAST_CHAR)) ? 0 : CC((Char) >> 8, (Char) & 0xff))

 /**
  * g_unicode_canonical_ordering:
  * @string: a UCS-4 encoded string.
  * @len: the maximum length of @string to use.
  *
  * Computes the canonical ordering of a string in-place.
  * This rearranges decomposed characters in the string
  * according to their combining classes.  See the Unicode
  * manual for more information.
  **/
 void
 g_unicode_canonical_ordering (gunichar *string,
 			      gsize     len)
 {
   gsize i;
   int swap = 1;

   while (swap)
     {
       int last;
       swap = 0;
       last = COMBINING_CLASS (string[0]);
       for (i = 0; i < len - 1; ++i)
 	{
 	  int next = COMBINING_CLASS (string[i + 1]);
 	  if (next != 0 && last > next)
 	    {
 	      gsize j;
 	      /* Percolate item leftward through string.  */
 	      for (j = i; j > 0; --j)
 		{
 		  gunichar t;
 		  if (COMBINING_CLASS (string[j]) <= next)
 		    break;
 		  t = string[j + 1];
 		  string[j + 1] = string[j];
 		  string[j] = t;
 		  swap = 1;
 		}
 	      /* We're re-entering the loop looking at the old
 		 character again.  */
 	      next = last;
 	    }
 	  last = next;
 	}
     }
 }

 static const guchar *
 find_decomposition (gunichar ch,
 		    gboolean compat)
 {
   int start = 0;
   int end = G_N_ELEMENTS (decomp_table);

   if (ch >= decomp_table[start].ch &&
       ch <= decomp_table[end - 1].ch)
     {
       while (TRUE)
 	{
 	  int half = (start + end) / 2;
 	  if (ch == decomp_table[half].ch)
 	    {
 	      int offset;

 	      if (compat)
 		{
 		  offset = decomp_table[half].compat_offset;
 		  if (offset == 0xff)
 		    offset = decomp_table[half].canon_offset;
 		}
 	      else
 		{
 		  offset = decomp_table[half].canon_offset;
 		  if (offset == 0xff)
 		    return NULL;
 		}

 	      return &(decomp_expansion_string[decomp_table[half].expansion_offset + offset]);
 	    }
 	  else if (half == start)
 	    break;
 	  else if (ch > decomp_table[half].ch)
 	    start = half;
 	  else
 	    end = half;
 	}
     }

   return NULL;
 }

 /**
  * g_unicode_canonical_decomposition:
  * @ch: a Unicode character.
  * @result_len: location to store the length of the return value.
  *
  * Computes the canonical decomposition of a Unicode character.
  *
  * Return value: a newly allocated string of Unicode characters.
  *   @result_len is set to the resulting length of the string.
  **/
 gunichar *
 g_unicode_canonical_decomposition (gunichar ch,
 				   gsize   *result_len)
 {
   const guchar *decomp = find_decomposition (ch, FALSE);
   gunichar *r;

   if (decomp)
     {
       /* Found it.  */
       int i, len;
       /* We store as a double-nul terminated string.  */
       for (len = 0; (decomp[len] || decomp[len + 1]);
 	   len += 2)
 	;

       /* We've counted twice as many bytes as there are
 	 characters.  */
       *result_len = len / 2;
       r = malloc (len / 2 * sizeof (gunichar));

       for (i = 0; i < len; i += 2)
 	{
 	  r[i / 2] = (decomp[i] << 8 | decomp[i + 1]);
 	}
     }
   else
     {
       /* Not in our table.  */
       r = malloc (sizeof (gunichar));
       *r = ch;
       *result_len = 1;
     }

   /* Supposedly following the Unicode 2.1.9 table means that the
      decompositions come out in canonical order.  I haven't tested
      this, but we rely on it here.  */
   return r;
 }

 #define CI(Page, Char) \
   ((compose_table[Page] >= G_UNICODE_MAX_TABLE_INDEX) \
    ? (compose_table[Page] - G_UNICODE_MAX_TABLE_INDEX) \
    : (compose_data[compose_table[Page]][Char]))

 #define COMPOSE_INDEX(Char) \
      (((Char) > (G_UNICODE_LAST_CHAR)) ? 0 : CI((Char) >> 8, (Char) & 0xff))

 gboolean
 combine (gunichar  a,
 	 gunichar  b,
 	 gunichar *result)
 {
   gushort index_a, index_b;

   index_a = COMPOSE_INDEX(a);
   if (index_a >= COMPOSE_FIRST_SINGLE_START && index_a < COMPOSE_SECOND_START)
     {
       if (b == compose_first_single[index_a - COMPOSE_FIRST_SINGLE_START][0])
 	{
 	  *result = compose_first_single[index_a - COMPOSE_FIRST_SINGLE_START][1];
 	  return TRUE;
 	}
       else
 	return FALSE;
     }

   index_b = COMPOSE_INDEX(b);
   if (index_b >= COMPOSE_SECOND_SINGLE_START)
     {
       if (a == compose_second_single[index_b - COMPOSE_SECOND_SINGLE_START][0])
 	{
 	  *result = compose_second_single[index_b - COMPOSE_SECOND_SINGLE_START][1];
 	  return TRUE;
 	}
       else
 	return FALSE;
     }

   if (index_a >= COMPOSE_FIRST_START && index_a < COMPOSE_FIRST_SINGLE_START &&
       index_b >= COMPOSE_SECOND_START && index_a < COMPOSE_SECOND_SINGLE_START)
     {
       gunichar res = compose_array[index_a - COMPOSE_FIRST_START][index_b - COMPOSE_SECOND_START];

       if (res)
 	{
 	  *result = res;
 	  return TRUE;
 	}
     }

   return FALSE;
 }

 gunichar *
 _g_utf8_normalize_wc (const gchar    *str,
 		      gssize          max_len,
 		      GNormalizeMode  mode)
 {
   gsize n_wc;
   gunichar *wc_buffer;
   const char *p;
   gsize last_start;
   gboolean do_compat = (mode == G_NORMALIZE_NFKC ||
 			mode == G_NORMALIZE_NFKD);
   gboolean do_compose = (mode == G_NORMALIZE_NFC ||
 			 mode == G_NORMALIZE_NFKC);

   n_wc = 0;
   p = str;
   while ((max_len < 0 || p < str + max_len) && *p)
     {
       gunichar wc = g_utf8_get_char (p);

       const guchar *decomp = find_decomposition (wc, do_compat);

       if (decomp)
 	{
 	  int len;
 	  /* We store as a double-nul terminated string.  */
 	  for (len = 0; (decomp[len] || decomp[len + 1]);
 	       len += 2)
 	    ;
 	  n_wc += len / 2;
 	}
       else
 	n_wc++;

       p = g_utf8_next_char (p);
     }

   wc_buffer = g_new (gunichar, n_wc + 1);

   last_start = 0;
   n_wc = 0;
   p = str;
   while ((max_len < 0 || p < str + max_len) && *p)
     {
       gunichar wc = g_utf8_get_char (p);
       const guchar *decomp;
       int cc;
       gsize old_n_wc = n_wc;

       decomp = find_decomposition (wc, do_compat);

       if (decomp)
 	{
 	  int len;
 	  /* We store as a double-nul terminated string.  */
 	  for (len = 0; (decomp[len] || decomp[len + 1]);
 	       len += 2)
 	    wc_buffer[n_wc++] = (decomp[len] << 8 | decomp[len + 1]);
 	}
       else
 	wc_buffer[n_wc++] = wc;

       if (n_wc > 0)
 	{
 	  cc = COMBINING_CLASS (wc_buffer[old_n_wc]);

 	  if (cc == 0)
 	    {
 	      g_unicode_canonical_ordering (wc_buffer + last_start, n_wc - last_start);
 	      last_start = old_n_wc;
 	    }
 	}

       p = g_utf8_next_char (p);
     }

   if (n_wc > 0)
     {
       g_unicode_canonical_ordering (wc_buffer + last_start, n_wc - last_start);
       last_start = n_wc;
     }

   wc_buffer[n_wc] = 0;

   /* All decomposed and reordered */


   if (do_compose && n_wc > 0)
     {
       gsize i, j;
       int last_cc = 0;
       last_start = 0;

       for (i = 0; i < n_wc; i++)
 	{
 	  int cc = COMBINING_CLASS (wc_buffer[i]);

 	  if (i > 0 &&
 	      (last_cc == 0 || last_cc != cc) &&
 	      combine (wc_buffer[last_start], wc_buffer[i],
 		       &wc_buffer[last_start]))
 	    {
 	      for (j = i + 1; j < n_wc; j++)
 		wc_buffer[j-1] = wc_buffer[j];
 	      n_wc--;
 	      i--;

 	      if (i == last_start)
 		last_cc = 0;
 	      else
 		last_cc = COMBINING_CLASS (wc_buffer[i-1]);

 	      continue;
 	    }

 	  if (cc == 0)
 	    last_start = i;

 	  last_cc = cc;
 	}
     }

   wc_buffer[n_wc] = 0;

   return wc_buffer;
 }

 /**
  * g_utf8_normalize:
  * @str: a UTF-8 encoded string.
  * @len: length of @str, in bytes, or -1 if @str is nul-terminated.
  * @mode: the type of normalization to perform.
  *
  * Converts a string into canonical form, standardizing
  * such issues as whether a character with an accent
  * is represented as a base character and combining
  * accent or as a single precomposed character. You
  * should generally call g_utf8_normalize() before
  * comparing two Unicode strings.
  *
  * The normalization mode %G_NORMALIZE_DEFAULT only
  * standardizes differences that do not affect the
  * text content, such as the above-mentioned accent
  * representation. %G_NORMALIZE_ALL also standardizes
  * the "compatibility" characters in Unicode, such
  * as SUPERSCRIPT THREE to the standard forms
  * (in this case DIGIT THREE). Formatting information
  * may be lost but for most text operations such
  * characters should be considered the same.
  * For example, g_utf8_collate() normalizes
  * with %G_NORMALIZE_ALL as its first step.
  *
  * %G_NORMALIZE_DEFAULT_COMPOSE and %G_NORMALIZE_ALL_COMPOSE
  * are like %G_NORMALIZE_DEFAULT and %G_NORMALIZE_ALL,
  * but returned a result with composed forms rather
  * than a maximally decomposed form. This is often
  * useful if you intend to convert the string to
  * a legacy encoding or pass it to a system with
  * less capable Unicode handling.
  *
  * Return value: a newly allocated string, that is the
  *   normalized form of @str.
  **/
 gchar *
 g_utf8_normalize (const gchar    *str,
 		  gssize          len,
 		  GNormalizeMode  mode)
 {
   gunichar *result_wc = _g_utf8_normalize_wc (str, len, mode);
   gchar *result;

   result = g_ucs4_to_utf8 (result_wc, -1, NULL, NULL, NULL);
   g_free (result_wc);

   return result;
 }
	/* decomp.c - Character decomposition.
	*
	* Copyright (C) 1999, 2000 Tom Tromey
	* Copyright 2000 Red Hat, Inc.
	*
	* The Gnome 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.
	*
	* The Gnome 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 the Gnome Library; see the file COPYING.LIB. If not,
	* write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
	* Boston, MA 02111-1307, USA.
	*/

	#include "glib.h"
	#include "gunidecomp.h"
	#include "gunicomp.h"

	#include <config.h>

	#include <stdlib.h>

	#define CC(Page, Char) \
	((combining_class_table[Page] >= G_UNICODE_MAX_TABLE_INDEX) \
	? (combining_class_table[Page] - G_UNICODE_MAX_TABLE_INDEX) \
	: (cclass_data[combining_class_table[Page]][Char]))

	#define COMBINING_CLASS(Char) \
	(((Char) > (G_UNICODE_LAST_CHAR)) ? 0 : CC((Char) >> 8, (Char) & 0xff))

	/**
	* g_unicode_canonical_ordering:
	* @string: a UCS-4 encoded string.
	* @len: the maximum length of @string to use.
	*
	* Computes the canonical ordering of a string in-place.
	* This rearranges decomposed characters in the string
	* according to their combining classes. See the Unicode
	* manual for more information.
	**/
	void
	g_unicode_canonical_ordering (gunichar *string,
	gsize len)
	{
	gsize i;
	int swap = 1;

	while (swap)
	{
	int last;
	swap = 0;
	last = COMBINING_CLASS (string[0]);
	for (i = 0; i < len - 1; ++i)
	{
	int next = COMBINING_CLASS (string[i + 1]);
	if (next != 0 && last > next)
	{
	gsize j;
	/* Percolate item leftward through string. */
	for (j = i; j > 0; --j)
	{
	gunichar t;
	if (COMBINING_CLASS (string[j]) <= next)
	break;
	t = string[j + 1];
	string[j + 1] = string[j];
	string[j] = t;
	swap = 1;
	}
	/* We're re-entering the loop looking at the old
	character again. */
	next = last;
	}
	last = next;
	}
	}
	}

	static const guchar *
	find_decomposition (gunichar ch,
	gboolean compat)
	{
	int start = 0;
	int end = G_N_ELEMENTS (decomp_table);

	if (ch >= decomp_table[start].ch &&
	ch <= decomp_table[end - 1].ch)
	{
	while (TRUE)
	{
	int half = (start + end) / 2;
	if (ch == decomp_table[half].ch)
	{
	int offset;

	if (compat)
	{
	offset = decomp_table[half].compat_offset;
	if (offset == 0xff)
	offset = decomp_table[half].canon_offset;
	}
	else
	{
	offset = decomp_table[half].canon_offset;
	if (offset == 0xff)
	return NULL;
	}

	return &(decomp_expansion_string[decomp_table[half].expansion_offset + offset]);
	}
	else if (half == start)
	break;
	else if (ch > decomp_table[half].ch)
	start = half;
	else
	end = half;
	}
	}

	return NULL;
	}

	/**
	* g_unicode_canonical_decomposition:
	* @ch: a Unicode character.
	* @result_len: location to store the length of the return value.
	*
	* Computes the canonical decomposition of a Unicode character.
	*
	* Return value: a newly allocated string of Unicode characters.
	* @result_len is set to the resulting length of the string.
	**/
	gunichar *
	g_unicode_canonical_decomposition (gunichar ch,
	gsize *result_len)
	{
	const guchar *decomp = find_decomposition (ch, FALSE);
	gunichar *r;

	if (decomp)
	{
	/* Found it. */
	int i, len;
	/* We store as a double-nul terminated string. */
	for (len = 0; (decomp[len] \|\| decomp[len + 1]);
	len += 2)
	;

	/* We've counted twice as many bytes as there are
	characters. */
	*result_len = len / 2;
	r = malloc (len / 2 * sizeof (gunichar));

	for (i = 0; i < len; i += 2)
	{
	r[i / 2] = (decomp[i] << 8 \| decomp[i + 1]);
	}
	}
	else
	{
	/* Not in our table. */
	r = malloc (sizeof (gunichar));
	*r = ch;
	*result_len = 1;
	}

	/* Supposedly following the Unicode 2.1.9 table means that the
	decompositions come out in canonical order. I haven't tested
	this, but we rely on it here. */
	return r;
	}

	#define CI(Page, Char) \
	((compose_table[Page] >= G_UNICODE_MAX_TABLE_INDEX) \
	? (compose_table[Page] - G_UNICODE_MAX_TABLE_INDEX) \
	: (compose_data[compose_table[Page]][Char]))

	#define COMPOSE_INDEX(Char) \
	(((Char) > (G_UNICODE_LAST_CHAR)) ? 0 : CI((Char) >> 8, (Char) & 0xff))

	gboolean
	combine (gunichar a,
	gunichar b,
	gunichar *result)
	{
	gushort index_a, index_b;

	index_a = COMPOSE_INDEX(a);
	if (index_a >= COMPOSE_FIRST_SINGLE_START && index_a < COMPOSE_SECOND_START)
	{
	if (b == compose_first_single[index_a - COMPOSE_FIRST_SINGLE_START][0])
	{
	*result = compose_first_single[index_a - COMPOSE_FIRST_SINGLE_START][1];
	return TRUE;
	}
	else
	return FALSE;
	}

	index_b = COMPOSE_INDEX(b);
	if (index_b >= COMPOSE_SECOND_SINGLE_START)
	{
	if (a == compose_second_single[index_b - COMPOSE_SECOND_SINGLE_START][0])
	{
	*result = compose_second_single[index_b - COMPOSE_SECOND_SINGLE_START][1];
	return TRUE;
	}
	else
	return FALSE;
	}

	if (index_a >= COMPOSE_FIRST_START && index_a < COMPOSE_FIRST_SINGLE_START &&
	index_b >= COMPOSE_SECOND_START && index_a < COMPOSE_SECOND_SINGLE_START)
	{
	gunichar res = compose_array[index_a - COMPOSE_FIRST_START][index_b - COMPOSE_SECOND_START];

	if (res)
	{
	*result = res;
	return TRUE;
	}
	}

	return FALSE;
	}

	gunichar *
	_g_utf8_normalize_wc (const gchar *str,
	gssize max_len,
	GNormalizeMode mode)
	{
	gsize n_wc;
	gunichar *wc_buffer;
	const char *p;
	gsize last_start;
	gboolean do_compat = (mode == G_NORMALIZE_NFKC \|\|
	mode == G_NORMALIZE_NFKD);
	gboolean do_compose = (mode == G_NORMALIZE_NFC \|\|
	mode == G_NORMALIZE_NFKC);

	n_wc = 0;
	p = str;
	while ((max_len < 0 \|\| p < str + max_len) && *p)
	{
	gunichar wc = g_utf8_get_char (p);

	const guchar *decomp = find_decomposition (wc, do_compat);

	if (decomp)
	{
	int len;
	/* We store as a double-nul terminated string. */
	for (len = 0; (decomp[len] \|\| decomp[len + 1]);
	len += 2)
	;
	n_wc += len / 2;
	}
	else
	n_wc++;

	p = g_utf8_next_char (p);
	}

	wc_buffer = g_new (gunichar, n_wc + 1);

	last_start = 0;
	n_wc = 0;
	p = str;
	while ((max_len < 0 \|\| p < str + max_len) && *p)
	{
	gunichar wc = g_utf8_get_char (p);
	const guchar *decomp;
	int cc;
	gsize old_n_wc = n_wc;

	decomp = find_decomposition (wc, do_compat);

	if (decomp)
	{
	int len;
	/* We store as a double-nul terminated string. */
	for (len = 0; (decomp[len] \|\| decomp[len + 1]);
	len += 2)
	wc_buffer[n_wc++] = (decomp[len] << 8 \| decomp[len + 1]);
	}
	else
	wc_buffer[n_wc++] = wc;

	if (n_wc > 0)
	{
	cc = COMBINING_CLASS (wc_buffer[old_n_wc]);

	if (cc == 0)
	{
	g_unicode_canonical_ordering (wc_buffer + last_start, n_wc - last_start);
	last_start = old_n_wc;
	}
	}

	p = g_utf8_next_char (p);
	}

	if (n_wc > 0)
	{
	g_unicode_canonical_ordering (wc_buffer + last_start, n_wc - last_start);
	last_start = n_wc;
	}

	wc_buffer[n_wc] = 0;

	/* All decomposed and reordered */


	if (do_compose && n_wc > 0)
	{
	gsize i, j;
	int last_cc = 0;
	last_start = 0;

	for (i = 0; i < n_wc; i++)
	{
	int cc = COMBINING_CLASS (wc_buffer[i]);

	if (i > 0 &&
	(last_cc == 0 \|\| last_cc != cc) &&
	combine (wc_buffer[last_start], wc_buffer[i],
	&wc_buffer[last_start]))
	{
	for (j = i + 1; j < n_wc; j++)
	wc_buffer[j-1] = wc_buffer[j];
	n_wc--;
	i--;

	if (i == last_start)
	last_cc = 0;
	else
	last_cc = COMBINING_CLASS (wc_buffer[i-1]);

	continue;
	}

	if (cc == 0)
	last_start = i;

	last_cc = cc;
	}
	}

	wc_buffer[n_wc] = 0;

	return wc_buffer;
	}

	/**
	* g_utf8_normalize:
	* @str: a UTF-8 encoded string.
	* @len: length of @str, in bytes, or -1 if @str is nul-terminated.
	* @mode: the type of normalization to perform.
	*
	* Converts a string into canonical form, standardizing
	* such issues as whether a character with an accent
	* is represented as a base character and combining
	* accent or as a single precomposed character. You
	* should generally call g_utf8_normalize() before
	* comparing two Unicode strings.
	*
	* The normalization mode %G_NORMALIZE_DEFAULT only
	* standardizes differences that do not affect the
	* text content, such as the above-mentioned accent
	* representation. %G_NORMALIZE_ALL also standardizes
	* the "compatibility" characters in Unicode, such
	* as SUPERSCRIPT THREE to the standard forms
	* (in this case DIGIT THREE). Formatting information
	* may be lost but for most text operations such
	* characters should be considered the same.
	* For example, g_utf8_collate() normalizes
	* with %G_NORMALIZE_ALL as its first step.
	*
	* %G_NORMALIZE_DEFAULT_COMPOSE and %G_NORMALIZE_ALL_COMPOSE
	* are like %G_NORMALIZE_DEFAULT and %G_NORMALIZE_ALL,
	* but returned a result with composed forms rather
	* than a maximally decomposed form. This is often
	* useful if you intend to convert the string to
	* a legacy encoding or pass it to a system with
	* less capable Unicode handling.
	*
	* Return value: a newly allocated string, that is the
	* normalized form of @str.
	**/
	gchar *
	g_utf8_normalize (const gchar *str,
	gssize len,
	GNormalizeMode mode)
	{
	gunichar *result_wc = _g_utf8_normalize_wc (str, len, mode);
	gchar *result;

	result = g_ucs4_to_utf8 (result_wc, -1, NULL, NULL, NULL);
	g_free (result_wc);

	return result;
	}