Add fallback implementation of strndup()

Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>
Reviewed-by: Jeremy Huddleston <jeremyhu@apple.com>
Linux test code fixed by: Keith Packard <keithp@keithp.com>

test/.gitignore

@@ -4,3 +4,4 @@ xtest
 list
 misc
 fixes
+string

test/Makefile.am

@@ -1,6 +1,6 @@
 if ENABLE_UNIT_TESTS
 SUBDIRS= . xi2
-noinst_PROGRAMS = xkb input xtest list misc fixes xfree86
+noinst_PROGRAMS = xkb input xtest list misc fixes xfree86 string
 check_LTLIBRARIES = libxservertest.la
 
 TESTS=$(noinst_PROGRAMS)

test/string.c

@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) 2011, Oracle and/or its affiliates. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ */
+
+/**
+ * Tests for fallback implementations of string handling routines
+ * provided in os/ subdirectory for some platforms.
+ */
+
+#ifdef HAVE_DIX_CONFIG_H
+#include <dix-config.h>
+#endif
+
+#include <assert.h>
+#include "os.h"
+
+/* Ensure we're testing our functions, even on platforms with libc versions */
+#include <string.h>
+#undef strndup
+#define strndup my_strndup
+char *
+strndup(const char *str, size_t n);
+
+#include "../os/strndup.c"
+
+static void strndup_checks(void)
+{
+    const char *sample="0123456789abcdef";
+    char *allofit;
+
+    char *firsthalf = strndup(sample, 8);
+    char *secondhalf = strndup(sample + 8, 8);
+
+    assert(strcmp(firsthalf,  "01234567") == 0);
+    assert(strcmp(secondhalf, "89abcdef") == 0);
+
+    free(firsthalf);
+    free(secondhalf);
+
+    allofit = strndup(sample, 20);
+    assert(strcmp(allofit, sample) == 0);
+    free(allofit);
+}
+
+int main(int argc, char** argv)
+{
+    strndup_checks();
+
+    return 0;
+}