1/* Conversion from UTF-16/UTF-32 to legacy encodings.
2   Copyright (C) 2002, 2006-2010 Free Software Foundation, Inc.
3
4   This program is free software: you can redistribute it and/or modify it
5   under the terms of the GNU Lesser General Public License as published
6   by the Free Software Foundation; either version 3 of the License, or
7   (at your option) any later version.
8
9   This program is distributed in the hope that it will be useful,
10   but WITHOUT ANY WARRANTY; without even the implied warranty of
11   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12   Lesser General Public License for more details.
13
14   You should have received a copy of the GNU Lesser General Public License
15   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
16
17char *
18FUNC (const char *tocode,
19      enum iconv_ilseq_handler handler,
20      const UNIT *src, size_t srclen,
21      size_t *offsets,
22      char *resultbuf, size_t *lengthp)
23{
24#if HAVE_UTF_NAME
25  size_t *scaled_offsets;
26  char *result;
27  size_t length;
28
29  if (offsets != NULL && srclen > 0)
30    {
31      scaled_offsets =
32        (size_t *) malloc (srclen * sizeof (UNIT) * sizeof (size_t));
33      if (scaled_offsets == NULL)
34        {
35          errno = ENOMEM;
36          return NULL;
37        }
38    }
39  else
40    scaled_offsets = NULL;
41
42  result = resultbuf;
43  length = *lengthp;
44  if (mem_iconveha ((const char *) src, srclen * sizeof (UNIT),
45                    UTF_NAME, tocode,
46                    handler == iconveh_question_mark, handler,
47                    scaled_offsets, &result, &length) < 0)
48    {
49      int saved_errno = errno;
50      free (scaled_offsets);
51      errno = saved_errno;
52      return NULL;
53    }
54
55  if (offsets != NULL)
56    {
57      /* Convert scaled_offsets[srclen * sizeof (UNIT)] to
58         offsets[srclen].  */
59      size_t i;
60
61      for (i = 0; i < srclen; i++)
62        offsets[i] = scaled_offsets[i * sizeof (UNIT)];
63      free (scaled_offsets);
64    }
65
66  if (result == NULL) /* when (resultbuf == NULL && length == 0)  */
67    {
68      result = (char *) malloc (1);
69      if (result == NULL)
70        {
71          errno = ENOMEM;
72          return NULL;
73        }
74    }
75  *lengthp = length;
76  return result;
77#else
78  uint8_t tmpbuf[4096];
79  size_t tmpbufsize = SIZEOF (tmpbuf);
80  uint8_t *utf8_src;
81  size_t utf8_srclen;
82  size_t *scaled_offsets;
83  char *result;
84
85  utf8_src = U_TO_U8 (src, srclen, tmpbuf, &tmpbufsize);
86  if (utf8_src == NULL)
87    return NULL;
88  utf8_srclen = tmpbufsize;
89
90  if (offsets != NULL && utf8_srclen > 0)
91    {
92      scaled_offsets = (size_t *) malloc (utf8_srclen * sizeof (size_t));
93      if (scaled_offsets == NULL)
94        {
95          if (utf8_src != tmpbuf)
96            free (utf8_src);
97          errno = ENOMEM;
98          return NULL;
99        }
100    }
101  else
102    scaled_offsets = NULL;
103
104  result = u8_conv_to_encoding (tocode, handler, utf8_src, utf8_srclen,
105                                scaled_offsets, resultbuf, lengthp);
106  if (result == NULL)
107    {
108      int saved_errno = errno;
109      free (scaled_offsets);
110      if (utf8_src != tmpbuf)
111        free (utf8_src);
112      errno = saved_errno;
113      return NULL;
114    }
115  if (offsets != NULL)
116    {
117      size_t iunit;     /* offset into src */
118      size_t i8;        /* offset into utf8_src */
119
120      for (iunit = 0; iunit < srclen; iunit++)
121        offsets[iunit] = (size_t)(-1);
122
123      iunit = 0;
124      i8 = 0;
125      while (iunit < srclen && i8 < utf8_srclen)
126        {
127          int countunit;
128          int count8;
129
130          offsets[iunit] = scaled_offsets[i8];
131
132          countunit = U_MBLEN (src + iunit, srclen - iunit);
133          count8 = u8_mblen (utf8_src + i8, utf8_srclen - i8);
134          if (countunit < 0 || count8 < 0)
135            abort ();
136          iunit += countunit;
137          i8 += count8;
138        }
139      /* Check that utf8_src has been traversed entirely.  */
140      if (i8 < utf8_srclen)
141        abort ();
142      /* Check that src has been traversed entirely, except possibly for an
143         incomplete sequence of units at the end.  */
144      if (iunit < srclen)
145        {
146          offsets[iunit] = *lengthp;
147          if (!(U_MBLEN (src + iunit, srclen - iunit) < 0))
148            abort ();
149        }
150      free (scaled_offsets);
151    }
152  if (utf8_src != tmpbuf)
153    free (utf8_src);
154  return result;
155#endif
156}
157