* Added POSIX function strndup(), closing ticket #3309.

git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@28939 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/posix/string.h

@@ -1,5 +1,5 @@
 /*
- * Copyright 2004, Haiku Inc. All Rights Reserved.
+ * Copyright 2004-2009, Haiku Inc. All Rights Reserved.
  * Distributed under the terms of the MIT License.
  */
 #ifndef _STRING_H_
@@ -58,6 +58,7 @@ extern int		strncasecmp(const char *string1, const char *string2, size_t length)
 extern char		*strcasestr(const char *string, const char *searchString);
 
 extern char		*strdup(const char *string);
+extern char		*strndup(const char* string, size_t size);
 extern char		*stpcpy(char *dest, const char *source);
 
 extern size_t	strlcat(char *dest, const char *source, size_t length);

src/system/libroot/posix/string/Jamfile

@@ -27,6 +27,7 @@ MergeObject posix_string.o :
 	strncat.c
 	strncmp.c
 	strncpy.c
+	strndup.cpp
 	strnlen.c
 	strpbrk.c
 	strrchr.c

src/system/libroot/posix/string/strndup.cpp

@@ -0,0 +1,30 @@
+/* 
+ * Copyright 2009, Axel Dörfler, axeld@pinc-software.de.
+ * Distributed under the terms of the MIT License.
+ */
+
+
+#include <string.h>
+#include <stdlib.h>
+
+
+extern "C" char*
+strndup(const char* string, size_t size)
+{
+	// While POSIX does not mention it, we handle NULL pointers gracefully
+	if (string == NULL)
+		return NULL;
+
+	size_t length = strlen(string);
+	if (length > size)
+		length = size;
+
+	char* copied = (char*)malloc(length + 1);
+	if (copied == NULL)
+		return NULL;
+
+	memcpy(copied, string, length);
+	copied[length] = '\0';
+
+	return copied;
+}