New modules 'unistr/u8-strspn', 'unistr/u16-strspn', 'unistr/u32-strspn'.

[gnulib.git] / lib / unistr / u-strspn.h

diff --git a/lib/unistr/u-strspn.h b/lib/unistr/u-strspn.h
new file mode 100644 (file)
index 0000000..1bfbc65
--- /dev/null
+++ b/lib/unistr/u-strspn.h
@@ -0,0 +1,56 @@
+/* Search for some characters in UTF-8/UTF-16/UTF-32 string.
+   Copyright (C) 1999, 2002, 2006 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 Library General Public License as published
+   by the Free Software Foundation; either version 2, 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
+   Library General Public License for more details.
+
+   You should have received a copy of the GNU Library General Public
+   License along with this program; if not, write to the Free Software
+   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
+   USA.  */
+
+size_t
+FUNC (const UNIT *str, const UNIT *accept)
+{
+  /* Optimize two cases.  */
+  if (accept[0] == 0)
+    return 0;
+  {
+    ucs4_t uc;
+    int count = U_STRMBTOUC (&uc, accept);
+    if (count >= 0 && accept[count] == 0)
+      {
+       const UNIT *ptr = str;
+       for (; *ptr != 0; ptr += count)
+         if (U_CMP (ptr, accept, count) != 0)
+           break;
+       return ptr - str;
+      }
+  }
+  /* General case.  */
+  {
+    const UNIT *ptr = str;
+
+    for (;;)
+      {
+       ucs4_t uc;
+       int count = U_STRMBTOUC (&uc, ptr);
+       if (count == 0)
+         return ptr - str;
+       if (count < 0)
+         break;
+       if (!U_STRCHR (accept, uc))
+         return ptr - str;
+       ptr += count;
+      }
+    return U_STRLEN (str);
+  }
+}