win32: import strndup from gnulib

3 files changed, 42 insertions, 0 deletions

diff --git a/include/mingw.h b/include/mingw.h
index c411a8106..c75b06330 100644
--- a/include/mingw.h
+++ b/include/mingw.h
@@ -200,6 +200,11 @@ int unsetenv(const char *env);
 #define mktemp mingw_mktemp
 
 /*
+ * string.h
+ */
+char *strndup(char const *s, size_t n);
+
+/*
  * strings.h
  */
 int ffs(int i);
diff --git a/win32/Kbuild b/win32/Kbuild
index f8c8fb5af..f3d0244d2 100644
--- a/win32/Kbuild
+++ b/win32/Kbuild
@@ -20,6 +20,7 @@ lib-$(CONFIG_PLATFORM_MINGW32) += regex.o
 lib-$(CONFIG_PLATFORM_MINGW32) += select.o
 lib-$(CONFIG_FEATURE_PRNG_SHELL) += sh_random.o
 lib-$(CONFIG_PLATFORM_MINGW32) += statfs.o
+lib-$(CONFIG_PLATFORM_MINGW32) += strndup.o
 lib-$(CONFIG_PLATFORM_MINGW32) += strptime.o
 lib-$(CONFIG_PLATFORM_MINGW32) += system.o
 lib-$(CONFIG_PLATFORM_MINGW32) += termios.o
diff --git a/win32/strndup.c b/win32/strndup.c
new file mode 100644
index 000000000..4d04609f6
--- /dev/null
+++ b/win32/strndup.c
@@ -0,0 +1,36 @@
+/* A replacement function, for systems that lack strndup.
+
+   Copyright (C) 1996-1998, 2001-2003, 2005-2007, 2009-2020 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 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 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 "libbb.h"
+
+#include <string.h>
+
+#include <stdlib.h>
+
+char *
+strndup (char const *s, size_t n)
+{
+  size_t len = strnlen (s, n);
+  char *new = malloc (len + 1);
+
+  if (new == NULL)
+    return NULL;
+
+  new[len] = '\0';
+  return memcpy (new, s, len);
+}