/* Search character in UTF-8 string.
- Copyright (C) 1999, 2002, 2006-2007, 2009-2010 Free Software Foundation,
+ Copyright (C) 1999, 2002, 2006-2007, 2009-2011 Free Software Foundation,
Inc.
Written by Bruno Haible <bruno@clisp.org>, 2002.
{
uint8_t c0 = c[0];
uint8_t c1 = c[1];
+ /* Search for { c0, c1 }. */
uint8_t s1 = s[1];
for (;;)
{
+ /* Here s[0] != 0, s[1] != 0.
+ Test whether s[0..1] == { c0, c1 }. */
if (s1 == c1)
{
if (*s == c0)
return (uint8_t *) s;
else
+ /* Skip the search at s + 1, because s[1] = c1 < c0. */
goto case2_skip2;
}
else
if (s1 == c0)
goto case2_skip1;
else
+ /* Skip the search at s + 1, because s[1] != c0. */
goto case2_skip2;
}
case2_skip2:
uint8_t c0 = c[0];
uint8_t c1 = c[1];
uint8_t c2 = c[2];
+ /* Search for { c0, c1, c2 }. */
uint8_t s2 = s[2];
for (;;)
{
+ /* Here s[0] != 0, s[1] != 0, s[2] != 0.
+ Test whether s[0..2] == { c0, c1, c2 }. */
if (s2 == c2)
{
if (s[1] == c1 && *s == c0)
return (uint8_t *) s;
- else if (c2 == c1)
- goto case3_skip1;
else
- goto case3_skip3;
+ /* If c2 != c1:
+ Skip the search at s + 1, because s[2] == c2 != c1.
+ Skip the search at s + 2, because s[2] == c2 < c0. */
+ if (c2 == c1)
+ goto case3_skip1;
+ else
+ goto case3_skip3;
}
else
{
if (s2 == c1)
goto case3_skip1;
else if (s2 == c0)
+ /* Skip the search at s + 1, because s[2] != c1. */
goto case3_skip2;
else
+ /* Skip the search at s + 1, because s[2] != c1.
+ Skip the search at s + 2, because s[2] != c0. */
goto case3_skip3;
}
case3_skip3:
break;
}
}
+ break;
case 4:
if (*s == 0 || s[1] == 0 || s[2] == 0 || s[3] == 0)
uint8_t c1 = c[1];
uint8_t c2 = c[2];
uint8_t c3 = c[3];
+ /* Search for { c0, c1, c2, c3 }. */
uint8_t s3 = s[3];
for (;;)
{
+ /* Here s[0] != 0, s[1] != 0, s[2] != 0, s[3] != 0.
+ Test whether s[0..3] == { c0, c1, c2, c3 }. */
if (s3 == c3)
{
if (s[2] == c2 && s[1] == c1 && *s == c0)
return (uint8_t *) s;
- else if (c3 == c2)
- goto case4_skip1;
- else if (c3 == c1)
- goto case4_skip2;
else
- goto case4_skip4;
+ /* If c3 != c2:
+ Skip the search at s + 1, because s[3] == c3 != c2.
+ If c3 != c1:
+ Skip the search at s + 2, because s[3] == c3 != c1.
+ Skip the search at s + 3, because s[3] == c3 < c0. */
+ if (c3 == c2)
+ goto case4_skip1;
+ else if (c3 == c1)
+ goto case4_skip2;
+ else
+ goto case4_skip4;
}
else
{
if (s3 == c2)
goto case4_skip1;
else if (s3 == c1)
+ /* Skip the search at s + 1, because s[3] != c2. */
goto case4_skip2;
else if (s3 == c0)
+ /* Skip the search at s + 1, because s[3] != c2.
+ Skip the search at s + 2, because s[3] != c1. */
goto case4_skip3;
else
+ /* Skip the search at s + 1, because s[3] != c2.
+ Skip the search at s + 2, because s[3] != c1.
+ Skip the search at s + 3, because s[3] != c0. */
goto case4_skip4;
}
case4_skip4:
break;
}
}
+ break;
}
return NULL;