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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/u32-prev.c
Imported Upstream version 0.9.1upstream/0.9.1
Diffstat (limited to 'lib/unistr/u32-prev.c')
-rw-r--r--lib/unistr/u32-prev.c39
1 files changed, 39 insertions, 0 deletions
diff --git a/lib/unistr/u32-prev.c b/lib/unistr/u32-prev.c
new file mode 100644
index 0000000..bc20c93
--- /dev/null
+++ b/lib/unistr/u32-prev.c
@@ -0,0 +1,39 @@
+/* Iterate over previous character in UTF-32 string.
+ Copyright (C) 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"
+
+const uint32_t *
+u32_prev (ucs4_t *puc, const uint32_t *s, const uint32_t *start)
+{
+ if (s != start)
+ {
+ uint32_t c_1 = s[-1];
+
+#if CONFIG_UNICODE_SAFETY
+ if (c_1 < 0xd800 || (c_1 >= 0xe000 && c_1 < 0x110000))
+#endif
+ {
+ *puc = c_1;
+ return s - 1;
+ }
+ }
+ return NULL;
+}