Added C++ redirect sample

samples/CMakeLists.txt

@@ -26,6 +26,7 @@ set(SAMPLES
   description.cc
   simple.cc
   theories.cc
+  redirect.cc
 )
 
 set(SCRIPTS

samples/redirect.cc

@@ -0,0 +1,56 @@
+#include <criterion/criterion.h>
+#include <criterion/redirect.h>
+
+#include <string>
+#include <iostream>
+#include <fstream>
+#include <cctype>
+
+// Testing stdout/stderr
+
+void redirect_all_std(void) {
+    cr_redirect_stdout();
+    cr_redirect_stderr();
+}
+
+Test(redirect, test_outputs, .init = redirect_all_std) {
+    std::FILE* f_stdout = cr_get_redirected_stdout();
+
+    std::cout << "foo" << std::flush;
+
+    cr_assert_file_contents_match_str(f_stdout, "foo");
+
+    std::FILE* f_stderr = cr_get_redirected_stderr();
+
+    std::cerr << "bar" << std::flush;
+
+    cr_assert_file_contents_match_str(f_stderr, "bar");
+}
+
+// Testing general I/O with sample command-line rot13
+
+char rot13_char(char c) {
+    return std::isalpha(c) ? (c - 'a' + 13) % 26 + 'a' : c;
+}
+
+void rot13_io(void) {
+    std::string s;
+
+    std::cin >> s;
+    for (size_t i = 0; i < s.length(); ++i)
+        s[i] = rot13_char(s[i]);
+    std::cout << s << std::flush;
+}
+
+Test(redirect, rot13, .init = cr_redirect_stdout) {
+    std::FILE* f_stdin = cr_get_redirected_stdin();
+    std::ofstream f_cin(f_stdin);
+
+    f_cin << "the quick brown fox jumps over the lazy dog";
+    f_cin.close();
+
+    rot13_io();
+
+    std::FILE* f_stdout = cr_get_redirected_stdout();
+    cr_assert_file_contents_match_str(f_stdout, "gur dhvpx oebja sbk whzcf bire gur ynml qbt");
+}