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authorAndreas Rottmann <a.rottmann@gmx.at>2009-09-14 12:32:44 +0200
committerAndreas Rottmann <a.rottmann@gmx.at>2009-09-14 12:32:44 +0200
commitfa095a4504cbe668e4244547e2c141597bea4ecf (patch)
tree06135820a286ffec47804e75fbf8a147e92acd2e /lib/unistr/u16-strrchr.c
Imported Upstream version 0.9.1upstream/0.9.1
Diffstat (limited to 'lib/unistr/u16-strrchr.c')
-rw-r--r--lib/unistr/u16-strrchr.c64
1 files changed, 64 insertions, 0 deletions
diff --git a/lib/unistr/u16-strrchr.c b/lib/unistr/u16-strrchr.c
new file mode 100644
index 0000000..b3c7ab0
--- /dev/null
+++ b/lib/unistr/u16-strrchr.c
@@ -0,0 +1,64 @@
+/* Search character in UTF-16 string.
+ Copyright (C) 1999, 2002, 2006-2007 Free Software Foundation, Inc.
+ Written by Bruno Haible <bruno@clisp.org>, 2002.
+
+ 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/>. */
+
+#include <config.h>
+
+/* Specification. */
+#include "unistr.h"
+
+uint16_t *
+u16_strrchr (const uint16_t *s, ucs4_t uc)
+{
+ /* Calling u16_strlen and then searching from the other end would cause more
+ memory accesses. Avoid that, at the cost of a few more comparisons. */
+ uint16_t *result = NULL;
+ uint16_t c[2];
+
+ if (uc < 0x10000)
+ {
+ uint16_t c0 = uc;
+
+ for (;; s++)
+ {
+ if (*s == c0)
+ result = (uint16_t *) s;
+ if (*s == 0)
+ break;
+ }
+ }
+ else
+ switch (u16_uctomb_aux (c, uc, 2))
+ {
+ case 2:
+ if (*s)
+ {
+ uint16_t c0 = c[0];
+ uint16_t c1 = c[1];
+
+ /* FIXME: Maybe walking the string via u16_mblen is a win? */
+ for (;; s++)
+ {
+ if (s[1] == 0)
+ break;
+ if (*s == c0 && s[1] == c1)
+ result = (uint16_t *) s;
+ }
+ }
+ break;
+ }
+ return result;
+}