summaryrefslogtreecommitdiff
path: root/lib/unicase/u-ct-casefold.h
diff options
context:
space:
mode:
Diffstat (limited to 'lib/unicase/u-ct-casefold.h')
-rw-r--r--lib/unicase/u-ct-casefold.h107
1 files changed, 107 insertions, 0 deletions
diff --git a/lib/unicase/u-ct-casefold.h b/lib/unicase/u-ct-casefold.h
new file mode 100644
index 00000000..d97be264
--- /dev/null
+++ b/lib/unicase/u-ct-casefold.h
@@ -0,0 +1,107 @@
+/* Casefolding mapping for Unicode substrings (locale dependent).
+ Copyright (C) 2009 Free Software Foundation, Inc.
+ Written by Bruno Haible <bruno@clisp.org>, 2009.
+
+ This program 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 3 of the License, or
+ (at your option) any later version.
+
+ This program 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 <http://www.gnu.org/licenses/>. */
+
+UNIT *
+FUNC (const UNIT *s, size_t n,
+ casing_prefix_context_t prefix_context,
+ casing_suffix_context_t suffix_context,
+ const char *iso639_language,
+ uninorm_t nf,
+ UNIT *resultbuf, size_t *lengthp)
+{
+ /* Implement the three definitions of caseless matching, as described in
+ Unicode 5.0, section "Default caseless matching":
+ - If no normalization is requested, simply apply the casefolding.
+ X -> toCasefold(X).
+ - If canonical normalization is requested, apply it, and apply an NFD
+ before.
+ X -> NFD(toCasefold(NFD(X))).
+ - If compatibility normalization is requested, apply it twice, apply
+ the normalization after each, and apply an NFD before:
+ X -> NFKD(toCasefold(NFKD(toCasefold(NFD(X))))). */
+ if (nf == NULL)
+ /* X -> toCasefold(X) */
+ return U_CASEMAP (s, n, prefix_context, suffix_context, iso639_language,
+ uc_tocasefold, offsetof (struct special_casing_rule, casefold[0]),
+ NULL,
+ resultbuf, lengthp);
+ else
+ {
+ uninorm_t nfd = uninorm_decomposing_form (nf);
+ /* X -> nf(toCasefold(NFD(X))) or
+ X -> nf(toCasefold(nfd(toCasefold(NFD(X))))) */
+ int repeat = (uninorm_is_compat_decomposing (nf) ? 2 : 1);
+ UNIT tmpbuf1[2048 / sizeof (UNIT)];
+ UNIT tmpbuf2[2048 / sizeof (UNIT)];
+ UNIT *tmp1;
+ size_t tmp1_length;
+ UNIT *tmp2;
+ size_t tmp2_length;
+
+ tmp1_length = sizeof (tmpbuf1) / sizeof (UNIT);
+ tmp1 = U_NORMALIZE (UNINORM_NFD, s, n, tmpbuf1, &tmp1_length);
+ if (tmp1 == NULL)
+ /* errno is set here. */
+ return NULL;
+
+ do
+ {
+ tmp2_length = sizeof (tmpbuf2) / sizeof (UNIT);
+ tmp2 = U_CASEMAP (tmp1, tmp1_length,
+ prefix_context, suffix_context, iso639_language,
+ uc_tocasefold, offsetof (struct special_casing_rule, casefold[0]),
+ NULL,
+ tmpbuf2, &tmp2_length);
+ if (tmp2 == NULL)
+ {
+ int saved_errno = errno;
+ if (tmp1 != tmpbuf1)
+ free (tmp1);
+ errno = saved_errno;
+ return NULL;
+ }
+
+ if (tmp1 != tmpbuf1)
+ free (tmp1);
+
+ if (repeat > 1)
+ {
+ tmp1_length = sizeof (tmpbuf1) / sizeof (UNIT);
+ tmp1 = U_NORMALIZE (nfd, tmp2, tmp2_length,
+ tmpbuf1, &tmp1_length);
+ }
+ else
+ /* Last run through this loop. */
+ tmp1 = U_NORMALIZE (nf, tmp2, tmp2_length,
+ resultbuf, lengthp);
+ if (tmp1 == NULL)
+ {
+ int saved_errno = errno;
+ if (tmp2 != tmpbuf2)
+ free (tmp2);
+ errno = saved_errno;
+ return NULL;
+ }
+
+ if (tmp2 != tmpbuf2)
+ free (tmp2);
+ }
+ while (--repeat > 0);
+
+ return tmp1;
+ }
+}