1 files changed, 127 insertions, 0 deletions
diff --git a/src/searchutils.c b/src/searchutils.c
new file mode 100644
index 0000000..1f21a0e
--- /dev/null
+++ b/src/searchutils.c
@@ -0,0 +1,127 @@
+/* searchutils.c - helper subroutines for grep's matchers.
+   Copyright 1992, 1998, 2000, 2007, 2009-2016 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3, 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 General Public License for more details.
+
+   You should have received a copy of the GNU 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.  */
+
+#include <config.h>
+
+#define SEARCH_INLINE _GL_EXTERN_INLINE
+#define SYSTEM_INLINE _GL_EXTERN_INLINE
+#include "search.h"
+
+#define NCHAR (UCHAR_MAX + 1)
+
+size_t mbclen_cache[NCHAR];
+
+void
+kwsinit (kwset_t *kwset)
+{
+  static char trans[NCHAR];
+  int i;
+
+  if (match_icase && MB_CUR_MAX == 1)
+    {
+      for (i = 0; i < NCHAR; ++i)
+        trans[i] = toupper (i);
+
+      *kwset = kwsalloc (trans);
+    }
+  else
+    *kwset = kwsalloc (NULL);
+
+  if (!*kwset)
+    xalloc_die ();
+}
+
+/* Initialize a cache of mbrlen values for each of its 1-byte inputs.  */
+void
+build_mbclen_cache (void)
+{
+  int i;
+
+  for (i = CHAR_MIN; i <= CHAR_MAX; ++i)
+    {
+      char c = i;
+      unsigned char uc = i;
+      mbstate_t mbs = { 0 };
+      size_t len = mbrlen (&c, 1, &mbs);
+      mbclen_cache[uc] = len ? len : 1;
+    }
+}
+
+/* In the buffer *MB_START, return the number of bytes needed to go
+   back from CUR to the previous boundary, where a "boundary" is the
+   start of a multibyte character or is an error-encoding byte.  The
+   buffer ends at END (i.e., one past the address of the buffer's last
+   byte).  If CUR is already at a boundary, return 0.  If *MB_START is
+   greater than or equal to CUR, return the negative value CUR - *MB_START.
+
+   When returning zero, set *MB_START to CUR.  When returning a
+   positive value, set *MB_START to the next boundary after CUR, or to
+   END if there is no such boundary.  When returning a negative value,
+   leave *MB_START alone.  */
+ptrdiff_t
+mb_goback (char const **mb_start, char const *cur, char const *end)
+{
+  const char *p = *mb_start;
+  const char *p0 = p;
+  mbstate_t cur_state;
+
+  memset (&cur_state, 0, sizeof cur_state);
+
+  while (p < cur)
+    {
+      size_t clen = mb_clen (p, end - p, &cur_state);
+
+      if ((size_t) -2 <= clen)
+        {
+          /* An invalid sequence, or a truncated multibyte character.
+             Treat it as a single byte character.  */
+          clen = 1;
+          memset (&cur_state, 0, sizeof cur_state);
+        }
+      p0 = p;
+      p += clen;
+    }
+
+  *mb_start = p;
+  return p == cur ? 0 : cur - p0;
+}
+
+/* In the buffer BUF, return the wide character that is encoded just
+   before CUR.  The buffer ends at END.  Return WEOF if there is no
+   wide character just before CUR.  */
+wint_t
+mb_prev_wc (char const *buf, char const *cur, char const *end)
+{
+  if (cur == buf)
+    return WEOF;
+  char const *p = buf;
+  cur--;
+  cur -= mb_goback (&p, cur, end);
+  return mb_next_wc (cur, end);
+}
+
+/* Return the wide character that is encoded at CUR.  The buffer ends
+   at END.  Return WEOF if there is no wide character encoded at CUR.  */
+wint_t
+mb_next_wc (char const *cur, char const *end)
+{
+  wchar_t wc;
+  mbstate_t mbs = { 0 };
+  return (end - cur != 0 && mbrtowc (&wc, cur, end - cur, &mbs) < (size_t) -2
+          ? wc : WEOF);
+}