/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: 2025-10-13 06:15

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	69.7k	{
22	69.7k	int (decomposer) (ucs4_t uc, ucs4_t decomposition) = nf->decomposer;
23	69.7k	ucs4_t (*composer) (ucs4_t uc1, ucs4_t uc2) = nf->composer;
24
25		/* The result being accumulated. */
26	69.7k	UNIT *result;
27	69.7k	size_t length;
28	69.7k	size_t allocated;
29		/* The buffer for sorting. */
30	69.7k	#define SORTBUF_PREALLOCATED 64
31	69.7k	struct ucs4_with_ccc sortbuf_preallocated[2 * SORTBUF_PREALLOCATED];
32	69.7k	struct ucs4_with_ccc sortbuf; / array of size 2 * sortbuf_allocated */
33	69.7k	size_t sortbuf_allocated;
34	69.7k	size_t sortbuf_count;
35
36		/* Initialize the accumulator. */
37	69.7k	if (resultbuf == NULL)
38	69.7k	{
39	69.7k	result = NULL;
40	69.7k	allocated = 0;
41	69.7k	}
42	0	else
43	0	{
44	0	result = resultbuf;
45	0	allocated = *lengthp;
46	0	}
47	69.7k	length = 0;
48
49		/* Initialize the buffer for sorting. */
50	69.7k	sortbuf = sortbuf_preallocated;
51	69.7k	sortbuf_allocated = SORTBUF_PREALLOCATED;
52	69.7k	sortbuf_count = 0;
53
54	69.7k	{
55	69.7k	const UNIT *s_end = s + n;
56
57	69.7k	for (;;)
58	797k	{
59	797k	int count;
60	797k	ucs4_t decomposed[UC_DECOMPOSITION_MAX_LENGTH];
61	797k	int decomposed_count;
62	797k	int i;
63
64	797k	if (s < s_end)
65	728k	{
66		/* Fetch the next character. */
67	728k	count = U_MBTOUC_UNSAFE (&decomposed[0], s, s_end - s);
68	728k	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	728k	{
77	728k	int curr;
78
79	1.52M	for (curr = 0; curr < decomposed_count; )
80	797k	{
81		/* Invariant: decomposed[0..curr-1] is fully decomposed, i.e.
82		all elements are atomic. */
83	797k	ucs4_t curr_decomposed[UC_DECOMPOSITION_MAX_LENGTH];
84	797k	int curr_decomposed_count;
85
86	797k	curr_decomposed_count = decomposer (decomposed[curr], curr_decomposed);
87	797k	if (curr_decomposed_count >= 0)
88	34.8k	{
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	34.8k	int shift = curr_decomposed_count - 1;
93
94	34.8k	if (shift < 0)
95	0	abort ();
96	34.8k	if (shift > 0)
97	34.1k	{
98	34.1k	int j;
99
100	34.1k	decomposed_count += shift;
101	34.1k	if (decomposed_count > UC_DECOMPOSITION_MAX_LENGTH)
102	0	abort ();
103	42.9k	for (j = decomposed_count - 1 - shift; j > curr; j--)
104	8.80k	decomposed[j + shift] = decomposed[j];
105	34.1k	}
106	103k	for (; shift >= 0; shift--)
107	69.0k	decomposed[curr + shift] = curr_decomposed[shift];
108	34.8k	}
109	762k	else
110	762k	{
111		/* decomposed[curr] is atomic. */
112	762k	curr++;
113	762k	}
114	797k	}
115	728k	}
116	728k	}
117	69.7k	else
118	69.7k	{
119	69.7k	count = 0;
120	69.7k	decomposed_count = 0;
121	69.7k	}
122
123	797k	i = 0;
124	797k	for (;;)
125	1.56M	{
126	1.56M	ucs4_t uc;
127	1.56M	int ccc;
128
129	1.56M	if (s < s_end)
130	1.49M	{
131		/* Fetch the next character from the decomposition. */
132	1.49M	if (i == decomposed_count)
133	728k	break;
134	762k	uc = decomposed[i];
135	762k	ccc = uc_combining_class (uc);
136	762k	}
137	69.7k	else
138	69.7k	{
139		/* End of string reached. */
140	69.7k	uc = 0;
141	69.7k	ccc = 0;
142	69.7k	}
143
144	832k	if (ccc == 0)
145	707k	{
146	707k	size_t j;
147
148		/* Apply the canonical ordering algorithm to the accumulated
149		sequence of characters. */
150	707k	if (sortbuf_count > 1)
151	24.4k	gl_uninorm_decompose_merge_sort_inplace (sortbuf, sortbuf_count,
152	24.4k	sortbuf + sortbuf_count);
153
154	707k	if (composer != NULL)
155	707k	{
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	707k	if (sortbuf_count > 0 && sortbuf[0].ccc == 0)
177	637k	{
178	732k	for (j = 1; j < sortbuf_count; )
179	95.3k	{
180	95.3k	if (sortbuf[j].ccc > sortbuf[j - 1].ccc)
181	32.7k	{
182	32.7k	ucs4_t combined =
183	32.7k	composer (sortbuf[0].code, sortbuf[j].code);
184	32.7k	if (combined)
185	14.2k	{
186	14.2k	size_t k;
187
188	14.2k	sortbuf[0].code = combined;
189		/* sortbuf[0].ccc = 0, still valid. */
190	53.8k	for (k = j + 1; k < sortbuf_count; k++)
191	39.6k	sortbuf[k - 1] = sortbuf[k];
192	14.2k	sortbuf_count--;
193	14.2k	continue;
194	14.2k	}
195	32.7k	}
196	81.1k	j++;
197	81.1k	}
198	637k	if (s < s_end && sortbuf_count == 1)
199	562k	{
200	562k	ucs4_t combined =
201	562k	composer (sortbuf[0].code, uc);
202	562k	if (combined)
203	6.85k	{
204	6.85k	uc = combined;
205	6.85k	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	6.85k	sortbuf_count = 0;
210	6.85k	}
211	562k	}
212	637k	}
213	707k	}
214
215	1.44M	for (j = 0; j < sortbuf_count; j++)
216	741k	{
217	741k	ucs4_t muc = sortbuf[j].code;
218
219		/* Append muc to the result accumulator. */
220	741k	if (length < allocated)
221	670k	{
222	670k	int ret =
223	670k	U_UCTOMB (result + length, muc, allocated - length);
224	670k	if (ret == -1)
225	0	{
226	0	errno = EINVAL;
227	0	goto fail;
228	0	}
229	670k	if (ret >= 0)
230	670k	{
231	670k	length += ret;
232	670k	goto done_appending;
233	670k	}
234	670k	}
235	70.3k	{
236	70.3k	size_t old_allocated = allocated;
237	70.3k	size_t new_allocated = 2 * old_allocated;
238	70.3k	if (new_allocated < 64)
239	67.2k	new_allocated = 64;
240	70.3k	if (new_allocated < old_allocated) /* integer overflow? */
241	0	abort ();
242	70.3k	{
243	70.3k	UNIT *larger_result;
244	70.3k	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	3.05k	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	3.05k	else
266	3.05k	{
267	3.05k	larger_result =
268	3.05k	(UNIT ) realloc (result, new_allocated sizeof (UNIT));
269	3.05k	if (larger_result == NULL)
270	0	{
271	0	errno = ENOMEM;
272	0	goto fail;
273	0	}
274	3.05k	}
275	70.3k	result = larger_result;
276	70.3k	allocated = new_allocated;
277	70.3k	{
278	70.3k	int ret =
279	70.3k	U_UCTOMB (result + length, muc, allocated - length);
280	70.3k	if (ret == -1)
281	0	{
282	0	errno = EINVAL;
283	0	goto fail;
284	0	}
285	70.3k	if (ret < 0)
286	0	abort ();
287	70.3k	length += ret;
288	70.3k	goto done_appending;
289	70.3k	}
290	70.3k	}
291	70.3k	}
292	741k	done_appending: ;
293	741k	}
294
295		/* sortbuf is now empty. */
296	707k	sortbuf_count = 0;
297	707k	}
298
299	832k	if (!(s < s_end))
300		/* End of string reached. */
301	69.7k	break;
302
303		/* Append (uc, ccc) to sortbuf. */
304	762k	if (sortbuf_count == sortbuf_allocated)
305	632	{
306	632	struct ucs4_with_ccc *new_sortbuf;
307
308	632	sortbuf_allocated = 2 * sortbuf_allocated;
309	632	if (sortbuf_allocated < sortbuf_count) /* integer overflow? */
310	0	abort ();
311	632	new_sortbuf =
312	632	(struct ucs4_with_ccc ) malloc (2 sortbuf_allocated * sizeof (struct ucs4_with_ccc));
313	632	if (new_sortbuf == NULL)
314	0	{
315	0	errno = ENOMEM;
316	0	goto fail;
317	0	}
318	632	memcpy (new_sortbuf, sortbuf,
319	632	sortbuf_count * sizeof (struct ucs4_with_ccc));
320	632	if (sortbuf != sortbuf_preallocated)
321	632	free (sortbuf);
322	632	sortbuf = new_sortbuf;
323	632	}
324	762k	sortbuf[sortbuf_count].code = uc;
325	762k	sortbuf[sortbuf_count].ccc = ccc;
326	762k	sortbuf_count++;
327
328	762k	i++;
329	762k	}
330
331	797k	if (!(s < s_end))
332		/* End of string reached. */
333	69.7k	break;
334
335	728k	s += count;
336	728k	}
337	69.7k	}
338
339	69.7k	if (length == 0)
340	2.50k	{
341	2.50k	if (result == NULL)
342	2.50k	{
343		/* Return a non-NULL value. NULL means error. */
344	2.50k	result = (UNIT *) malloc (1);
345	2.50k	if (result == NULL)
346	0	{
347	0	errno = ENOMEM;
348	0	goto fail;
349	0	}
350	2.50k	}
351	2.50k	}
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	69.7k	if (sortbuf_count > 0)
363	0	abort ();
364	69.7k	if (sortbuf != sortbuf_preallocated)
365	69.7k	free (sortbuf);
366
367	69.7k	*lengthp = length;
368	69.7k	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	69.7k	}