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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 /sysdeps/generic/strncpy.c
initial import
Diffstat (limited to 'sysdeps/generic/strncpy.c')
-rw-r--r--sysdeps/generic/strncpy.c82
1 files changed, 82 insertions, 0 deletions
diff --git a/sysdeps/generic/strncpy.c b/sysdeps/generic/strncpy.c
new file mode 100644
index 0000000000..460e0baca4
--- /dev/null
+++ b/sysdeps/generic/strncpy.c
@@ -0,0 +1,82 @@
+/* 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 <string.h>
+#include <memcopy.h>
+
+char *
+DEFUN(strncpy, (s1, s2, n), char *s1 AND CONST char *s2 AND size_t n)
+{
+ reg_char c;
+ char *s = s1;
+
+ --s1;
+
+ if (n >= 4)
+ {
+ size_t n4 = n >> 2;
+
+ for (;;)
+ {
+ c = *s2++;
+ *++s1 = c;
+ if (c == '\0')
+ break;
+ c = *s2++;
+ *++s1 = c;
+ if (c == '\0')
+ break;
+ c = *s2++;
+ *++s1 = c;
+ if (c == '\0')
+ break;
+ c = *s2++;
+ *++s1 = c;
+ if (c == '\0')
+ break;
+ if (--n4 == 0)
+ goto last_chars;
+ }
+ n = n - (s1 - s) - 1;
+ if (n == 0)
+ return s;
+ goto zero_fill;
+ }
+
+ last_chars:
+ n &= 3;
+ if (n == 0)
+ return s;
+
+ do
+ {
+ c = *s2++;
+ *++s1 = c;
+ if (--n == 0)
+ return s;
+ }
+ while (c != '\0');
+
+ zero_fill:
+ do
+ *++s1 = '\0';
+ while (--n > 0);
+
+ return s;
+}