From d1cc563ccfb5cd053d33d996ff6a7fbb7bb94011 Mon Sep 17 00:00:00 2001
From: Antonio Galea <antonio.galea@gmail.com>
Date: Thu, 10 Oct 2019 14:56:58 +0200
Subject: [PATCH] USBUS CDC ACM STDIO: test for the buffering code

fixes #12384
---
 tests/usbus_cdc_acm_stdio/main.c | 32 +++++++++++++++++++++++++++++++-
 1 file changed, 31 insertions(+), 1 deletion(-)

diff --git a/tests/usbus_cdc_acm_stdio/main.c b/tests/usbus_cdc_acm_stdio/main.c
index e342013afd..c41f763540 100644
--- a/tests/usbus_cdc_acm_stdio/main.c
+++ b/tests/usbus_cdc_acm_stdio/main.c
@@ -18,16 +18,46 @@
  */
 
 #include <stdio.h>
+#include <stdlib.h>
 
 #include "shell.h"
 #include "shell_commands.h"
 
+static int cmd_text(int argc, char **argv)
+{
+    char *usage = "text [length]\n";
+    if (argc != 2) {
+        puts(usage);
+        return -1;
+    }
+    int n = atoi(argv[1]);
+    if (n <= 0) {
+        puts(usage);
+        return -1;
+    }
+    for (int i=0; i < n; i++) {
+        if (i && (i % 80 == 0)) {
+            puts("");
+        }
+        putc('0' + (i % 10), stdout);
+    }
+    puts("");
+    return 0;
+}
+
+
+static const shell_command_t shell_commands[] = {
+    { "text",  "Generates long text for testing stdio buffer",  cmd_text },
+    { NULL, NULL, NULL }
+};
+
+
 int main(void)
 {
     (void) puts("RIOT USB CDC ACM shell test");
 
     char line_buf[SHELL_DEFAULT_BUFSIZE];
-    shell_run(NULL, line_buf, SHELL_DEFAULT_BUFSIZE);
+    shell_run(shell_commands, line_buf, SHELL_DEFAULT_BUFSIZE);
 
     return 0;
 }