From 027426793cc7b9fd4e721d436722284e110767bc Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ga=C3=ABtan=20Harter?= <gaetan.harter@fu-berlin.de>
Date: Sat, 23 Mar 2019 14:20:18 +0100
Subject: [PATCH] test_utils_interactive_sync: add a helper for synchronizing
 tests

Add an implementation that waits for 's' to print 'START' and return.
If 'r' is given is prints 'READY' to allow querying for state.

The help and answered string have to be different to not match the other.
Using puts/getchar was smaller than using `stdio_read/stdio_write` on the
example I tested with `esp32`.
---
 sys/Makefile                                  |  3 ++
 sys/Makefile.dep                              |  2 +
 sys/include/test_utils/interactive_sync.h     | 42 +++++++++++++++++++
 sys/test_utils/Makefile.dep                   |  3 ++
 sys/test_utils/interactive_sync/Makefile      |  3 ++
 .../interactive_sync/interactive_sync.c       | 20 +++++++++
 6 files changed, 73 insertions(+)
 create mode 100644 sys/include/test_utils/interactive_sync.h
 create mode 100644 sys/test_utils/Makefile.dep
 create mode 100644 sys/test_utils/interactive_sync/Makefile
 create mode 100644 sys/test_utils/interactive_sync/interactive_sync.c

diff --git a/sys/Makefile b/sys/Makefile
index 058697f249..1926dabe36 100644
--- a/sys/Makefile
+++ b/sys/Makefile
@@ -25,6 +25,9 @@ endif
 ifneq (,$(filter shell_commands,$(USEMODULE)))
   DIRS += shell/commands
 endif
+ifneq (,$(filter test_utils_interactive_sync,$(USEMODULE)))
+  DIRS += test_utils/interactive_sync
+endif
 ifneq (,$(filter net_help,$(USEMODULE)))
   DIRS += net/crosslayer/net_help
 endif
diff --git a/sys/Makefile.dep b/sys/Makefile.dep
index f9afc587e3..dcddeac2bc 100644
--- a/sys/Makefile.dep
+++ b/sys/Makefile.dep
@@ -9,3 +9,5 @@ endif
 ifneq (,$(filter prng_fortuna,$(USEMODULE)))
   CFLAGS += -DCRYPTO_AES
 endif
+
+include $(RIOTBASE)/sys/test_utils/Makefile.dep
diff --git a/sys/include/test_utils/interactive_sync.h b/sys/include/test_utils/interactive_sync.h
new file mode 100644
index 0000000000..b27a571f2d
--- /dev/null
+++ b/sys/include/test_utils/interactive_sync.h
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2019 Freie Universität Berlin
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @defgroup    test_utils_interactive_sync Test interactive synchronization
+ * @ingroup     sys
+ * @brief       Utility function for synchronizing before a test
+ *
+ * @{
+ * @file
+ * @brief       Synchronization for normally non interactive tests
+ *
+ * @author      Gaëtan Harter <gaetan.harter@fu-berlin.de>
+ */
+
+#ifndef TEST_UTILS_INTERACTIVE_SYNC_H
+#define TEST_UTILS_INTERACTIVE_SYNC_H
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief   Wait for the tester to start test
+ *
+ * @details Wait for a 's' character to return
+ *
+ */
+void test_utils_interactive_sync(void);
+
+
+#ifdef __cplusplus
+}
+#endif
+#endif /* TEST_UTILS_INTERACTIVE_SYNC_H */
+/** @} */
diff --git a/sys/test_utils/Makefile.dep b/sys/test_utils/Makefile.dep
new file mode 100644
index 0000000000..4bafa543b8
--- /dev/null
+++ b/sys/test_utils/Makefile.dep
@@ -0,0 +1,3 @@
+ifneq (,$(filter test_utils_interactive_sync,$(USEMODULE)))
+  USEMODULE += stdin
+endif
diff --git a/sys/test_utils/interactive_sync/Makefile b/sys/test_utils/interactive_sync/Makefile
new file mode 100644
index 0000000000..e22cec26b0
--- /dev/null
+++ b/sys/test_utils/interactive_sync/Makefile
@@ -0,0 +1,3 @@
+MODULE = test_utils_interactive_sync
+
+include $(RIOTBASE)/Makefile.base
diff --git a/sys/test_utils/interactive_sync/interactive_sync.c b/sys/test_utils/interactive_sync/interactive_sync.c
new file mode 100644
index 0000000000..6dba6ed425
--- /dev/null
+++ b/sys/test_utils/interactive_sync/interactive_sync.c
@@ -0,0 +1,20 @@
+#include <stdio.h>
+#include "test_utils/interactive_sync.h"
+
+void test_utils_interactive_sync(void)
+{
+    char c = '\0'; /* Print help on first loop */
+    do {
+        if (c == 'r') {
+            /* This one should have a different case than the help message
+             * otherwise we match it when using 'expect' */
+            puts("READY");
+        }
+        else if (c != '\n' && c != '\r') {
+            puts("Help: Press s to start test, r to print it is ready");
+        }
+        c = getchar();
+    } while (c != 's');
+
+    puts("START");
+}