1 files changed, 45 insertions, 0 deletions
diff --git a/lib/xmemdup0.c b/lib/xmemdup0.c
new file mode 100644
index 0000000..7cedeb5
--- /dev/null
+++ b/lib/xmemdup0.c
@@ -0,0 +1,45 @@
+/* xmemdup0.c -- copy a block of arbitrary bytes, plus a trailing NUL
+
+   Copyright (C) 2008-2023 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 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+#include "xmemdup0.h"
+#include "xalloc.h"
+
+#include <string.h>
+
+/* Clone an arbitrary block of bytes P of size S, with error checking,
+   and include a terminating NUL byte.  P is of type 'void const *',
+   to make it easier to use this with other mem* functions that return
+   'void *', but since appending a NUL byte only makes sense on bytes,
+   the return type is 'char *'.
+
+   The terminating NUL makes it safe to use strlen or rawmemchr to
+   check for embedded NUL; it also speeds up algorithms such as escape
+   sequence processing on arbitrary memory, by making it always safe
+   to read the byte after the escape character rather than having to
+   check if each escape character is the last byte in the object.  */
+
+char *
+xmemdup0 (void const *p, size_t s)
+{
+  char *result = xcharalloc (s + 1);
+  if (s > 0)
+    memcpy (result, p, s);
+  result[s] = 0;
+  return result;
+}