summaryrefslogtreecommitdiff
path: root/string/strxfrm.c
diff options
context:
space:
mode:
authorRoland McGrath <roland@gnu.org>1995-02-18 01:27:10 +0000
committerRoland McGrath <roland@gnu.org>1995-02-18 01:27:10 +0000
commit28f540f45bbacd939bfd07f213bcad2bf730b1bf (patch)
tree15f07c4c43d635959c6afee96bde71fb1b3614ee /string/strxfrm.c
downloadglibc-28f540f45bbacd939bfd07f213bcad2bf730b1bf.tar.gz
initial import
Diffstat (limited to 'string/strxfrm.c')
-rw-r--r--string/strxfrm.c76
1 files changed, 76 insertions, 0 deletions
diff --git a/string/strxfrm.c b/string/strxfrm.c
new file mode 100644
index 0000000000..cdca280e78
--- /dev/null
+++ b/string/strxfrm.c
@@ -0,0 +1,76 @@
+/* Copyright (C) 1991 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library 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 of the
+License, or (at your option) any later version.
+
+The GNU C Library 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 the GNU C Library; see the file COPYING.LIB. If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA. */
+
+#include <ansidecl.h>
+#include <localeinfo.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+
+/* Transform SRC into a form such that the result of strcmp
+ on two strings that have been transformed by strxfrm is
+ the same as the result of strcoll on the two strings before
+ their transformation. The transformed string is put in at
+ most N characters of DEST and its length is returned. */
+size_t
+DEFUN(strxfrm, (dest, src, n), char *dest AND CONST char *src AND size_t n)
+{
+ CONST unsigned char *CONST values
+ = _collate_info != NULL ? _collate_info->values : NULL;
+ CONST unsigned char *CONST offsets
+ = _collate_info != NULL ? _collate_info->offsets : NULL;
+ register size_t done = 0;
+
+ while (*src != '\0')
+ {
+ CONST unsigned char c = *src++;
+
+ ++done;
+ if (offsets != NULL && offsets[c] != 0)
+ {
+ ++done;
+ if (offsets[c] == CHAR_MAX)
+ ++done;
+ }
+ if (done < n && dest != NULL)
+ {
+ if (values == NULL)
+ *dest++ = c;
+ else if (values[c] == UCHAR_MAX && offsets[c] == 0)
+ /* This is a non-collating element. Skip it. */
+ ;
+ else if (values[c] == UCHAR_MAX && offsets[c] == CHAR_MAX)
+ {
+ /* This element collates lower than anything else. */
+ *dest++ = '\001';
+ *dest++ = '\001';
+ *dest++ = '\001';
+ }
+ else
+ {
+ *dest++ = values[c];
+ *dest++ = offsets[c];
+ }
+ }
+ }
+
+ if (dest != NULL)
+ *dest = '\0';
+ return done;
+}