/src/libidn2/unistring/uninorm/u-normalize-internal.h

Source
/* Decomposition and composition of Unicode strings.
   Copyright (C) 2009-2025 Free Software Foundation, Inc.
   Written by Bruno Haible <bruno@clisp.org>, 2009.

   This file 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 file 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 program.  If not, see <https://www.gnu.org/licenses/>.  */

UNIT *
FUNC (uninorm_t nf, const UNIT *s, size_t n,
      UNIT *resultbuf, size_t *lengthp)
{
  int (*decomposer) (ucs4_t uc, ucs4_t *decomposition) = nf->decomposer;
  ucs4_t (*composer) (ucs4_t uc1, ucs4_t uc2) = nf->composer;

  /* The result being accumulated.  */
  UNIT *result;
  size_t length;
  size_t allocated;
  /* The buffer for sorting.  */
  #define SORTBUF_PREALLOCATED 64
  struct ucs4_with_ccc sortbuf_preallocated[2 * SORTBUF_PREALLOCATED];
  struct ucs4_with_ccc *sortbuf; /* array of size 2 * sortbuf_allocated */
  size_t sortbuf_allocated;
  size_t sortbuf_count;

  /* Initialize the accumulator.  */
  if (resultbuf == NULL)
    {
      result = NULL;
      allocated = 0;
    }
  else
    {
      result = resultbuf;
      allocated = *lengthp;
    }
  length = 0;

  /* Initialize the buffer for sorting.  */
  sortbuf = sortbuf_preallocated;
  sortbuf_allocated = SORTBUF_PREALLOCATED;
  sortbuf_count = 0;

  {
    const UNIT *s_end = s + n;

    for (;;)
      {
        int count;
        ucs4_t decomposed[UC_DECOMPOSITION_MAX_LENGTH];
        int decomposed_count;
        int i;

        if (s < s_end)
          {
            /* Fetch the next character.  */
            count = U_MBTOUC_UNSAFE (&decomposed[0], s, s_end - s);
            decomposed_count = 1;

            /* Decompose it, recursively.
               It would be possible to precompute the recursive decomposition
               and store it in a table.  But this would significantly increase
               the size of the decomposition tables, because for example for
               U+1FC1 the recursive canonical decomposition and the recursive
               compatibility decomposition are different.  */
            {
              int curr;

              for (curr = 0; curr < decomposed_count; )
                {
                  /* Invariant: decomposed[0..curr-1] is fully decomposed, i.e.
                     all elements are atomic.  */
                  ucs4_t curr_decomposed[UC_DECOMPOSITION_MAX_LENGTH];
                  int curr_decomposed_count;

                  curr_decomposed_count = decomposer (decomposed[curr], curr_decomposed);
                  if (curr_decomposed_count >= 0)
                    {
                      /* Move curr_decomposed[0..curr_decomposed_count-1] over
                         decomposed[curr], making room.  It's not worth using
                         memcpy() here, since the counts are so small.  */
                      int shift = curr_decomposed_count - 1;

                      if (shift < 0)
                        abort ();
                      if (shift > 0)
                        {
                          int j;

                          decomposed_count += shift;
                          if (decomposed_count > UC_DECOMPOSITION_MAX_LENGTH)
                            abort ();
                          for (j = decomposed_count - 1 - shift; j > curr; j--)
                            decomposed[j + shift] = decomposed[j];
                        }
                      for (; shift >= 0; shift--)
                        decomposed[curr + shift] = curr_decomposed[shift];
                    }
                  else
                    {
                      /* decomposed[curr] is atomic.  */
                      curr++;
                    }
                }
            }
          }
        else
          {
            count = 0;
            decomposed_count = 0;
          }

        i = 0;
        for (;;)
          {
            ucs4_t uc;
            int ccc;

            if (s < s_end)
              {
                /* Fetch the next character from the decomposition.  */
                if (i == decomposed_count)
                  break;
                uc = decomposed[i];
                ccc = uc_combining_class (uc);
              }
            else
              {
                /* End of string reached.  */
                uc = 0;
                ccc = 0;
              }

            if (ccc == 0)
              {
                size_t j;

                /* Apply the canonical ordering algorithm to the accumulated
                   sequence of characters.  */
                if (sortbuf_count > 1)
                  gl_uninorm_decompose_merge_sort_inplace (sortbuf, sortbuf_count,
                                                           sortbuf + sortbuf_count);

                if (composer != NULL)
                  {
                    /* Attempt to combine decomposed characters, as specified
                       in the Unicode Standard Annex #15 "Unicode Normalization
                       Forms".  We need to check
                         1. whether the first accumulated character is a
                            "starter" (i.e. has ccc = 0).  This is usually the
                            case.  But when the string starts with a
                            non-starter, the sortbuf also starts with a
                            non-starter.  Btw, this check could also be
                            omitted, because the composition table has only
                            entries (code1, code2) for which code1 is a
                            starter; if the first accumulated character is not
                            a starter, no lookup will succeed.
                         2. If the sortbuf has more than one character, check
                            for each of these characters that are not "blocked"
                            from the starter (i.e. have a ccc that is higher
                            than the ccc of the previous character) whether it
                            can be combined with the first character.
                         3. If only one character is left in sortbuf, check
                            whether it can be combined with the next character
                            (also a starter).  */
                    if (sortbuf_count > 0 && sortbuf[0].ccc == 0)
                      {
                        for (j = 1; j < sortbuf_count; )
                          {
                            if (sortbuf[j].ccc > sortbuf[j - 1].ccc)
                              {
                                ucs4_t combined =
                                  composer (sortbuf[0].code, sortbuf[j].code);
                                if (combined)
                                  {
                                    size_t k;

                                    sortbuf[0].code = combined;
                                    /* sortbuf[0].ccc = 0, still valid.  */
                                    for (k = j + 1; k < sortbuf_count; k++)
                                      sortbuf[k - 1] = sortbuf[k];
                                    sortbuf_count--;
                                    continue;
                                  }
                              }
                            j++;
                          }
                        if (s < s_end && sortbuf_count == 1)
                          {
                            ucs4_t combined =
                              composer (sortbuf[0].code, uc);
                            if (combined)
                              {
                                uc = combined;
                                ccc = 0;
                                /* uc could be further combined with subsequent
                                   characters.  So don't put it into sortbuf[0] in
                                   this round, only in the next round.  */
                                sortbuf_count = 0;
                              }
                          }
                      }
                  }

                for (j = 0; j < sortbuf_count; j++)
                  {
                    ucs4_t muc = sortbuf[j].code;

                    /* Append muc to the result accumulator.  */
                    if (length < allocated)
                      {
                        int ret =
                          U_UCTOMB (result + length, muc, allocated - length);
                        if (ret == -1)
                          {
                            errno = EINVAL;
                            goto fail;
                          }
                        if (ret >= 0)
                          {
                            length += ret;
                            goto done_appending;
                          }
                      }
                    {
                      size_t old_allocated = allocated;
                      size_t new_allocated = 2 * old_allocated;
                      if (new_allocated < 64)
                        new_allocated = 64;
                      if (new_allocated < old_allocated) /* integer overflow? */
                        abort ();
                      {
                        UNIT *larger_result;
                        if (result == NULL)
                          {
                            larger_result =
                              (UNIT *) malloc (new_allocated * sizeof (UNIT));
                            if (larger_result == NULL)
                              {
                                errno = ENOMEM;
                                goto fail;
                              }
                          }
                        else if (result == resultbuf)
                          {
                            larger_result =
                              (UNIT *) malloc (new_allocated * sizeof (UNIT));
                            if (larger_result == NULL)
                              {
                                errno = ENOMEM;
                                goto fail;
                              }
                            U_CPY (larger_result, resultbuf, length);
                          }
                        else
                          {
                            larger_result =
                              (UNIT *) realloc (result, new_allocated * sizeof (UNIT));
                            if (larger_result == NULL)
                              {
                                errno = ENOMEM;
                                goto fail;
                              }
                          }
                        result = larger_result;
                        allocated = new_allocated;
                        {
                          int ret =
                            U_UCTOMB (result + length, muc, allocated - length);
                          if (ret == -1)
                            {
                              errno = EINVAL;
                              goto fail;
                            }
                          if (ret < 0)
                            abort ();
                          length += ret;
                          goto done_appending;
                        }
                      }
                    }
                   done_appending: ;
                  }

                /* sortbuf is now empty.  */
                sortbuf_count = 0;
              }

            if (!(s < s_end))
              /* End of string reached.  */
              break;

            /* Append (uc, ccc) to sortbuf.  */
            if (sortbuf_count == sortbuf_allocated)
              {
                struct ucs4_with_ccc *new_sortbuf;

                sortbuf_allocated = 2 * sortbuf_allocated;
                if (sortbuf_allocated < sortbuf_count) /* integer overflow? */
                  abort ();
                new_sortbuf =
                  (struct ucs4_with_ccc *) malloc (2 * sortbuf_allocated * sizeof (struct ucs4_with_ccc));
                if (new_sortbuf == NULL)
                  {
                    errno = ENOMEM;
                    goto fail;
                  }
                memcpy (new_sortbuf, sortbuf,
                        sortbuf_count * sizeof (struct ucs4_with_ccc));
                if (sortbuf != sortbuf_preallocated)
                  free (sortbuf);
                sortbuf = new_sortbuf;
              }
            sortbuf[sortbuf_count].code = uc;
            sortbuf[sortbuf_count].ccc = ccc;
            sortbuf_count++;

            i++;
          }

        if (!(s < s_end))
          /* End of string reached.  */
          break;

        s += count;
      }
  }

  if (length == 0)
    {
      if (result == NULL)
        {
          /* Return a non-NULL value.  NULL means error.  */
          result = (UNIT *) malloc (1);
          if (result == NULL)
            {
              errno = ENOMEM;
              goto fail;
            }
        }
    }
  else if (result != resultbuf && length < allocated)
    {
      /* Shrink the allocated memory if possible.  */
      UNIT *memory;

      memory = (UNIT *) realloc (result, length * sizeof (UNIT));
      if (memory != NULL)
        result = memory;
    }

  if (sortbuf_count > 0)
    abort ();
  if (sortbuf != sortbuf_preallocated)
    free (sortbuf);

  *lengthp = length;
  return result;

 fail:
  {
    int saved_errno = errno;
    if (sortbuf != sortbuf_preallocated)
      free (sortbuf);
    if (result != resultbuf)
      free (result);
    errno = saved_errno;
  }
  return NULL;
}

Coverage Report

Created: 2025-10-10 06:54

Line	Count	Source
1		/* Decomposition and composition of Unicode strings.
2		Copyright (C) 2009-2025 Free Software Foundation, Inc.
3		Written by Bruno Haible <bruno@clisp.org>, 2009.
4
5		This file is free software: you can redistribute it and/or modify
6		it under the terms of the GNU Lesser General Public License as
7		published by the Free Software Foundation; either version 2.1 of the
8		License, or (at your option) any later version.
9
10		This file is distributed in the hope that it will be useful,
11		but WITHOUT ANY WARRANTY; without even the implied warranty of
12		MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13		GNU Lesser General Public License for more details.
14
15		You should have received a copy of the GNU Lesser General Public License
16		along with this program. If not, see <https://www.gnu.org/licenses/>. */
17
18		UNIT *
19		FUNC (uninorm_t nf, const UNIT *s, size_t n,
20		UNIT resultbuf, size_t lengthp)
21	69.6k	{
22	69.6k	int (decomposer) (ucs4_t uc, ucs4_t decomposition) = nf->decomposer;
23	69.6k	ucs4_t (*composer) (ucs4_t uc1, ucs4_t uc2) = nf->composer;
24
25		/* The result being accumulated. */
26	69.6k	UNIT *result;
27	69.6k	size_t length;
28	69.6k	size_t allocated;
29		/* The buffer for sorting. */
30	69.6k	#define SORTBUF_PREALLOCATED 64
31	69.6k	struct ucs4_with_ccc sortbuf_preallocated[2 * SORTBUF_PREALLOCATED];
32	69.6k	struct ucs4_with_ccc sortbuf; / array of size 2 * sortbuf_allocated */
33	69.6k	size_t sortbuf_allocated;
34	69.6k	size_t sortbuf_count;
35
36		/* Initialize the accumulator. */
37	69.6k	if (resultbuf == NULL)
38	69.6k	{
39	69.6k	result = NULL;
40	69.6k	allocated = 0;
41	69.6k	}
42	0	else
43	0	{
44	0	result = resultbuf;
45	0	allocated = *lengthp;
46	0	}
47	69.6k	length = 0;
48
49		/* Initialize the buffer for sorting. */
50	69.6k	sortbuf = sortbuf_preallocated;
51	69.6k	sortbuf_allocated = SORTBUF_PREALLOCATED;
52	69.6k	sortbuf_count = 0;
53
54	69.6k	{
55	69.6k	const UNIT *s_end = s + n;
56
57	69.6k	for (;;)
58	790k	{
59	790k	int count;
60	790k	ucs4_t decomposed[UC_DECOMPOSITION_MAX_LENGTH];
61	790k	int decomposed_count;
62	790k	int i;
63
64	790k	if (s < s_end)
65	721k	{
66		/* Fetch the next character. */
67	721k	count = U_MBTOUC_UNSAFE (&decomposed[0], s, s_end - s);
68	721k	decomposed_count = 1;
69
70		/* Decompose it, recursively.
71		It would be possible to precompute the recursive decomposition
72		and store it in a table. But this would significantly increase
73		the size of the decomposition tables, because for example for
74		U+1FC1 the recursive canonical decomposition and the recursive
75		compatibility decomposition are different. */
76	721k	{
77	721k	int curr;
78
79	1.51M	for (curr = 0; curr < decomposed_count; )
80	788k	{
81		/* Invariant: decomposed[0..curr-1] is fully decomposed, i.e.
82		all elements are atomic. */
83	788k	ucs4_t curr_decomposed[UC_DECOMPOSITION_MAX_LENGTH];
84	788k	int curr_decomposed_count;
85
86	788k	curr_decomposed_count = decomposer (decomposed[curr], curr_decomposed);
87	788k	if (curr_decomposed_count >= 0)
88	34.1k	{
89		/* Move curr_decomposed[0..curr_decomposed_count-1] over
90		decomposed[curr], making room. It's not worth using
91		memcpy() here, since the counts are so small. */
92	34.1k	int shift = curr_decomposed_count - 1;
93
94	34.1k	if (shift < 0)
95	0	abort ();
96	34.1k	if (shift > 0)
97	33.3k	{
98	33.3k	int j;
99
100	33.3k	decomposed_count += shift;
101	33.3k	if (decomposed_count > UC_DECOMPOSITION_MAX_LENGTH)
102	0	abort ();
103	42.1k	for (j = decomposed_count - 1 - shift; j > curr; j--)
104	8.80k	decomposed[j + shift] = decomposed[j];
105	33.3k	}
106	101k	for (; shift >= 0; shift--)
107	67.5k	decomposed[curr + shift] = curr_decomposed[shift];
108	34.1k	}
109	754k	else
110	754k	{
111		/* decomposed[curr] is atomic. */
112	754k	curr++;
113	754k	}
114	788k	}
115	721k	}
116	721k	}
117	69.6k	else
118	69.6k	{
119	69.6k	count = 0;
120	69.6k	decomposed_count = 0;
121	69.6k	}
122
123	790k	i = 0;
124	790k	for (;;)
125	1.54M	{
126	1.54M	ucs4_t uc;
127	1.54M	int ccc;
128
129	1.54M	if (s < s_end)
130	1.47M	{
131		/* Fetch the next character from the decomposition. */
132	1.47M	if (i == decomposed_count)
133	721k	break;
134	754k	uc = decomposed[i];
135	754k	ccc = uc_combining_class (uc);
136	754k	}
137	69.6k	else
138	69.6k	{
139		/* End of string reached. */
140	69.6k	uc = 0;
141	69.6k	ccc = 0;
142	69.6k	}
143
144	824k	if (ccc == 0)
145	700k	{
146	700k	size_t j;
147
148		/* Apply the canonical ordering algorithm to the accumulated
149		sequence of characters. */
150	700k	if (sortbuf_count > 1)
151	22.9k	gl_uninorm_decompose_merge_sort_inplace (sortbuf, sortbuf_count,
152	22.9k	sortbuf + sortbuf_count);
153
154	700k	if (composer != NULL)
155	700k	{
156		/* Attempt to combine decomposed characters, as specified
157		in the Unicode Standard Annex #15 "Unicode Normalization
158		Forms". We need to check
159		1. whether the first accumulated character is a
160		"starter" (i.e. has ccc = 0). This is usually the
161		case. But when the string starts with a
162		non-starter, the sortbuf also starts with a
163		non-starter. Btw, this check could also be
164		omitted, because the composition table has only
165		entries (code1, code2) for which code1 is a
166		starter; if the first accumulated character is not
167		a starter, no lookup will succeed.
168		2. If the sortbuf has more than one character, check
169		for each of these characters that are not "blocked"
170		from the starter (i.e. have a ccc that is higher
171		than the ccc of the previous character) whether it
172		can be combined with the first character.
173		3. If only one character is left in sortbuf, check
174		whether it can be combined with the next character
175		(also a starter). */
176	700k	if (sortbuf_count > 0 && sortbuf[0].ccc == 0)
177	630k	{
178	724k	for (j = 1; j < sortbuf_count; )
179	93.6k	{
180	93.6k	if (sortbuf[j].ccc > sortbuf[j - 1].ccc)
181	31.1k	{
182	31.1k	ucs4_t combined =
183	31.1k	composer (sortbuf[0].code, sortbuf[j].code);
184	31.1k	if (combined)
185	12.9k	{
186	12.9k	size_t k;
187
188	12.9k	sortbuf[0].code = combined;
189		/* sortbuf[0].ccc = 0, still valid. */
190	52.1k	for (k = j + 1; k < sortbuf_count; k++)
191	39.2k	sortbuf[k - 1] = sortbuf[k];
192	12.9k	sortbuf_count--;
193	12.9k	continue;
194	12.9k	}
195	31.1k	}
196	80.6k	j++;
197	80.6k	}
198	630k	if (s < s_end && sortbuf_count == 1)
199	555k	{
200	555k	ucs4_t combined =
201	555k	composer (sortbuf[0].code, uc);
202	555k	if (combined)
203	7.07k	{
204	7.07k	uc = combined;
205	7.07k	ccc = 0;
206		/* uc could be further combined with subsequent
207		characters. So don't put it into sortbuf[0] in
208		this round, only in the next round. */
209	7.07k	sortbuf_count = 0;
210	7.07k	}
211	555k	}
212	630k	}
213	700k	}
214
215	1.43M	for (j = 0; j < sortbuf_count; j++)
216	734k	{
217	734k	ucs4_t muc = sortbuf[j].code;
218
219		/* Append muc to the result accumulator. */
220	734k	if (length < allocated)
221	664k	{
222	664k	int ret =
223	664k	U_UCTOMB (result + length, muc, allocated - length);
224	664k	if (ret == -1)
225	0	{
226	0	errno = EINVAL;
227	0	goto fail;
228	0	}
229	664k	if (ret >= 0)
230	664k	{
231	664k	length += ret;
232	664k	goto done_appending;
233	664k	}
234	664k	}
235	70.2k	{
236	70.2k	size_t old_allocated = allocated;
237	70.2k	size_t new_allocated = 2 * old_allocated;
238	70.2k	if (new_allocated < 64)
239	67.2k	new_allocated = 64;
240	70.2k	if (new_allocated < old_allocated) /* integer overflow? */
241	0	abort ();
242	70.2k	{
243	70.2k	UNIT *larger_result;
244	70.2k	if (result == NULL)
245	67.2k	{
246	67.2k	larger_result =
247	67.2k	(UNIT ) malloc (new_allocated sizeof (UNIT));
248	67.2k	if (larger_result == NULL)
249	0	{
250	0	errno = ENOMEM;
251	0	goto fail;
252	0	}
253	67.2k	}
254	3.04k	else if (result == resultbuf)
255	0	{
256	0	larger_result =
257	0	(UNIT ) malloc (new_allocated sizeof (UNIT));
258	0	if (larger_result == NULL)
259	0	{
260	0	errno = ENOMEM;
261	0	goto fail;
262	0	}
263	0	U_CPY (larger_result, resultbuf, length);
264	0	}
265	3.04k	else
266	3.04k	{
267	3.04k	larger_result =
268	3.04k	(UNIT ) realloc (result, new_allocated sizeof (UNIT));
269	3.04k	if (larger_result == NULL)
270	0	{
271	0	errno = ENOMEM;
272	0	goto fail;
273	0	}
274	3.04k	}
275	70.2k	result = larger_result;
276	70.2k	allocated = new_allocated;
277	70.2k	{
278	70.2k	int ret =
279	70.2k	U_UCTOMB (result + length, muc, allocated - length);
280	70.2k	if (ret == -1)
281	0	{
282	0	errno = EINVAL;
283	0	goto fail;
284	0	}
285	70.2k	if (ret < 0)
286	0	abort ();
287	70.2k	length += ret;
288	70.2k	goto done_appending;
289	70.2k	}
290	70.2k	}
291	70.2k	}
292	734k	done_appending: ;
293	734k	}
294
295		/* sortbuf is now empty. */
296	700k	sortbuf_count = 0;
297	700k	}
298
299	824k	if (!(s < s_end))
300		/* End of string reached. */
301	69.6k	break;
302
303		/* Append (uc, ccc) to sortbuf. */
304	754k	if (sortbuf_count == sortbuf_allocated)
305	636	{
306	636	struct ucs4_with_ccc *new_sortbuf;
307
308	636	sortbuf_allocated = 2 * sortbuf_allocated;
309	636	if (sortbuf_allocated < sortbuf_count) /* integer overflow? */
310	0	abort ();
311	636	new_sortbuf =
312	636	(struct ucs4_with_ccc ) malloc (2 sortbuf_allocated * sizeof (struct ucs4_with_ccc));
313	636	if (new_sortbuf == NULL)
314	0	{
315	0	errno = ENOMEM;
316	0	goto fail;
317	0	}
318	636	memcpy (new_sortbuf, sortbuf,
319	636	sortbuf_count * sizeof (struct ucs4_with_ccc));
320	636	if (sortbuf != sortbuf_preallocated)
321	636	free (sortbuf);
322	636	sortbuf = new_sortbuf;
323	636	}
324	754k	sortbuf[sortbuf_count].code = uc;
325	754k	sortbuf[sortbuf_count].ccc = ccc;
326	754k	sortbuf_count++;
327
328	754k	i++;
329	754k	}
330
331	790k	if (!(s < s_end))
332		/* End of string reached. */
333	69.6k	break;
334
335	721k	s += count;
336	721k	}
337	69.6k	}
338
339	69.6k	if (length == 0)
340	2.44k	{
341	2.44k	if (result == NULL)
342	2.44k	{
343		/* Return a non-NULL value. NULL means error. */
344	2.44k	result = (UNIT *) malloc (1);
345	2.44k	if (result == NULL)
346	0	{
347	0	errno = ENOMEM;
348	0	goto fail;
349	0	}
350	2.44k	}
351	2.44k	}
352	67.2k	else if (result != resultbuf && length < allocated)
353	66.9k	{
354		/* Shrink the allocated memory if possible. */
355	66.9k	UNIT *memory;
356
357	66.9k	memory = (UNIT ) realloc (result, length sizeof (UNIT));
358	66.9k	if (memory != NULL)
359	66.9k	result = memory;
360	66.9k	}
361
362	69.6k	if (sortbuf_count > 0)
363	0	abort ();
364	69.6k	if (sortbuf != sortbuf_preallocated)
365	69.6k	free (sortbuf);
366
367	69.6k	*lengthp = length;
368	69.6k	return result;
369
370	0	fail:
371	0	{
372	0	int saved_errno = errno;
373	0	if (sortbuf != sortbuf_preallocated)
374	0	free (sortbuf);
375	0	if (result != resultbuf)
376	0	free (result);
377	0	errno = saved_errno;
378	0	}
379		return NULL;
380	69.6k	}