1/* Search character in UTF-8 string.
2   Copyright (C) 1999, 2002, 2006-2007, 2009-2010 Free Software Foundation,
3   Inc.
4   Written by Bruno Haible <bruno@clisp.org>, 2002.
5
6   This program is free software: you can redistribute it and/or modify it
7   under the terms of the GNU Lesser General Public License as published
8   by the Free Software Foundation; either version 3 of the License, or
9   (at your option) any later version.
10
11   This program is distributed in the hope that it will be useful,
12   but WITHOUT ANY WARRANTY; without even the implied warranty of
13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14   Lesser General Public License for more details.
15
16   You should have received a copy of the GNU Lesser General Public License
17   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
18
19#include <config.h>
20
21/* Specification.  */
22#include "unistr.h"
23
24uint8_t *
25u8_strchr (const uint8_t *s, ucs4_t uc)
26{
27  uint8_t c[6];
28
29  if (uc < 0x80)
30    {
31      uint8_t c0 = uc;
32
33      for (;; s++)
34        {
35          if (*s == c0)
36            break;
37          if (*s == 0)
38            goto notfound;
39        }
40      return (uint8_t *) s;
41    }
42  else
43    switch (u8_uctomb_aux (c, uc, 6))
44      {
45      case 2:
46        if (*s == 0)
47          goto notfound;
48        {
49          uint8_t c0 = c[0];
50          uint8_t c1 = c[1];
51
52          for (;; s++)
53            {
54              if (s[1] == 0)
55                goto notfound;
56              if (*s == c0 && s[1] == c1)
57                break;
58            }
59          return (uint8_t *) s;
60        }
61
62      case 3:
63        if (*s == 0 || s[1] == 0)
64          goto notfound;
65        {
66          uint8_t c0 = c[0];
67          uint8_t c1 = c[1];
68          uint8_t c2 = c[2];
69
70          for (;; s++)
71            {
72              if (s[2] == 0)
73                goto notfound;
74              if (*s == c0 && s[1] == c1 && s[2] == c2)
75                break;
76            }
77          return (uint8_t *) s;
78        }
79
80      case 4:
81        if (*s == 0 || s[1] == 0 || s[2] == 0)
82          goto notfound;
83        {
84          uint8_t c0 = c[0];
85          uint8_t c1 = c[1];
86          uint8_t c2 = c[2];
87          uint8_t c3 = c[3];
88
89          for (;; s++)
90            {
91              if (s[3] == 0)
92                goto notfound;
93              if (*s == c0 && s[1] == c1 && s[2] == c2 && s[3] == c3)
94                break;
95            }
96          return (uint8_t *) s;
97        }
98      }
99notfound:
100  return NULL;
101}
102