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authorJörg Frings-Fürst <debian@jff.email>2024-03-24 08:54:48 +0100
committerJörg Frings-Fürst <debian@jff.email>2024-03-24 08:54:48 +0100
commit163a663518f33bab48b28431972e580b366b4d49 (patch)
treef518ffabaca4a0b93f0103d617e803792d3b0b43 /lib/wcsstr-impl.h
parent1b3a8d5ad2ea2f099d514d9dd51ebf926a628076 (diff)
parentdd0000f7e25abe6c28d4329d324fd7fcab54094f (diff)
Merge branch 'release/debian/1.2-1'HEADdebian/1.2-1master
Diffstat (limited to 'lib/wcsstr-impl.h')
-rw-r--r--lib/wcsstr-impl.h56
1 files changed, 56 insertions, 0 deletions
diff --git a/lib/wcsstr-impl.h b/lib/wcsstr-impl.h
new file mode 100644
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--- /dev/null
+++ b/lib/wcsstr-impl.h
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+/* Locate a substring in a wide string.
+ Copyright (C) 1999, 2011-2024 Free Software Foundation, Inc.
+
+ 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/>. */
+
+/* Written by Eric Blake, 2008. */
+
+#define AVAILABLE(h, h_l, j, n_l) \
+ (!MEMCHR0 ((h) + (h_l), (j) + (n_l) - (h_l)) \
+ && ((h_l) = (j) + (n_l)))
+#include "wcs-two-way.h"
+
+RETURN_TYPE
+FUNC (const UNIT *haystack_start, const UNIT *needle_start)
+{
+ const UNIT *haystack = haystack_start;
+ const UNIT *needle = needle_start;
+ size_t needle_len; /* Length of NEEDLE. */
+ size_t haystack_len; /* Known minimum length of HAYSTACK. */
+ bool ok = true; /* True if NEEDLE is prefix of HAYSTACK. */
+
+ /* Determine length of NEEDLE, and in the process, make sure
+ HAYSTACK is at least as long (no point processing all of a long
+ NEEDLE if HAYSTACK is too short). */
+ while (*haystack && *needle)
+ ok &= *haystack++ == *needle++;
+ if (*needle)
+ return NULL;
+ if (ok)
+ return (RETURN_TYPE) haystack_start;
+
+ /* Reduce the size of haystack using STRCHR, since it has a smaller
+ linear coefficient than the Two-Way algorithm. */
+ needle_len = needle - needle_start;
+ haystack = STRCHR (haystack_start + 1, *needle_start);
+ if (!haystack || __builtin_expect (needle_len == 1, 0))
+ return (RETURN_TYPE) haystack;
+ needle -= needle_len;
+ haystack_len = (haystack > haystack_start + needle_len ? 1
+ : needle_len + haystack_start - haystack);
+
+ /* Perform the search. */
+ return two_way_short_needle (haystack, haystack_len,
+ needle, needle_len);
+}