summaryrefslogtreecommitdiff
path: root/lib/unistr/u8-strchr.c
diff options
context:
space:
mode:
Diffstat (limited to 'lib/unistr/u8-strchr.c')
-rw-r--r--lib/unistr/u8-strchr.c335
1 files changed, 170 insertions, 165 deletions
diff --git a/lib/unistr/u8-strchr.c b/lib/unistr/u8-strchr.c
index 355a12c7..30468be1 100644
--- a/lib/unistr/u8-strchr.c
+++ b/lib/unistr/u8-strchr.c
@@ -1,5 +1,5 @@
/* Search character in UTF-8 string.
- Copyright (C) 1999, 2002, 2006-2007, 2009-2024 Free Software Foundation,
+ Copyright (C) 1999, 2002, 2006-2007, 2009-2026 Free Software Foundation,
Inc.
Written by Bruno Haible <bruno@clisp.org>, 2002.
@@ -24,6 +24,9 @@
License and of the GNU General Public License along with this
program. If not, see <https://www.gnu.org/licenses/>. */
+/* Don't use the const-improved function macros in this compilation unit. */
+#define _LIBUNISTRING_NO_CONST_GENERICS
+
#include <config.h>
/* Specification. */
@@ -34,8 +37,6 @@
uint8_t *
u8_strchr (const uint8_t *s, ucs4_t uc)
{
- uint8_t c[6];
-
if (uc < 0x80)
{
uint8_t c0 = uc;
@@ -62,187 +63,191 @@ u8_strchr (const uint8_t *s, ucs4_t uc)
}
}
else
+ {
/* Loops equivalent to strstr, optimized for a specific length (2, 3, 4)
of the needle. We use an algorithm similar to Boyer-Moore which
is documented in lib/unistr/u8-chr.c. There is additional
complication because we need to check after every byte for
a NUL byte, but the idea is the same. */
- switch (u8_uctomb_aux (c, uc, 6))
- {
- case 2:
- if (*s == 0 || s[1] == 0)
- break;
- {
- uint8_t c0 = c[0];
- uint8_t c1 = c[1];
- /* Search for { c0, c1 }. */
- uint8_t s1 = s[1];
+ uint8_t c[6];
- 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:
- s++;
- s1 = s[1];
- if (s[1] == 0)
- break;
- case2_skip1:
- s++;
- s1 = s[1];
- if (s[1] == 0)
- break;
- }
- }
- break;
+ switch (u8_uctomb_aux (c, uc, 6))
+ {
+ case 2:
+ if (*s == 0 || s[1] == 0)
+ break;
+ {
+ uint8_t c0 = c[0];
+ uint8_t c1 = c[1];
+ /* Search for { c0, c1 }. */
+ uint8_t s1 = s[1];
- case 3:
- if (*s == 0 || s[1] == 0 || s[2] == 0)
+ 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:
+ s++;
+ s1 = s[1];
+ if (s[1] == 0)
+ break;
+ case2_skip1:
+ s++;
+ s1 = s[1];
+ if (s[1] == 0)
+ break;
+ }
+ }
break;
- {
- 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:
- 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)
+ case 3:
+ if (*s == 0 || s[1] == 0 || s[2] == 0)
+ break;
+ {
+ 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:
+ 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;
- }
- 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:
- s++;
- s2 = s[2];
- if (s[2] == 0)
- break;
- case3_skip2:
- s++;
- s2 = s[2];
- if (s[2] == 0)
- break;
- case3_skip1:
- s++;
- s2 = s[2];
- if (s[2] == 0)
- break;
- }
- }
- break;
-
- case 4:
- if (*s == 0 || s[1] == 0 || s[2] == 0 || s[3] == 0)
+ }
+ case3_skip3:
+ s++;
+ s2 = s[2];
+ if (s[2] == 0)
+ break;
+ case3_skip2:
+ s++;
+ s2 = s[2];
+ if (s[2] == 0)
+ break;
+ case3_skip1:
+ s++;
+ s2 = s[2];
+ if (s[2] == 0)
+ break;
+ }
+ }
break;
- {
- uint8_t c0 = c[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:
- 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)
+ case 4:
+ if (*s == 0 || s[1] == 0 || s[2] == 0 || s[3] == 0)
+ break;
+ {
+ uint8_t c0 = c[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:
+ 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 (c3 == c1)
+ 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;
- }
- 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:
- s++;
- s3 = s[3];
- if (s[3] == 0)
- break;
- case4_skip3:
- s++;
- s3 = s[3];
- if (s[3] == 0)
- break;
- case4_skip2:
- s++;
- s3 = s[3];
- if (s[3] == 0)
- break;
- case4_skip1:
- s++;
- s3 = s[3];
- if (s[3] == 0)
- break;
- }
+ }
+ case4_skip4:
+ s++;
+ s3 = s[3];
+ if (s[3] == 0)
+ break;
+ case4_skip3:
+ s++;
+ s3 = s[3];
+ if (s[3] == 0)
+ break;
+ case4_skip2:
+ s++;
+ s3 = s[3];
+ if (s[3] == 0)
+ break;
+ case4_skip1:
+ s++;
+ s3 = s[3];
+ if (s[3] == 0)
+ break;
+ }
+ }
+ break;
}
- break;
- }
+ }
return NULL;
}
generated by cgit v1.2.3 (git 2.25.1) at 2026-03-11 22:26:45 +0000