Make sure that apps/openssl prefixes its output with '# ' during tests

The reason to do this is that some output might start with an 'ok',
which TAP catches and takes for TAP output.  The TAP compatible way is
to make all output it shouldn't catch look like comments.

We do this by setting the environment variable HARNESS_OSSL_PREFIX
during tests.  When that is set, apps/openssl uses BIO_f_linebuffer
and sets its prefix to the content of that environment variable.
Reviewed-by: NRich Salz <rsalz@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/5224)

apps/apps.c

 /*
- * Copyright 1995-2017 The OpenSSL Project Authors. All Rights Reserved.
+ * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
  *
  * Licensed under the OpenSSL license (the "License").  You may not use
  * this file except in compliance with the License.  You can obtain a copy
@@ -2428,14 +2428,26 @@ BIO *dup_bio_in(int format)
                       BIO_NOCLOSE | (istext(format) ? BIO_FP_TEXT : 0));
 }
 
+static BIO_METHOD *prefix_method = NULL;
+
 BIO *dup_bio_out(int format)
 {
     BIO *b = BIO_new_fp(stdout,
                         BIO_NOCLOSE | (istext(format) ? BIO_FP_TEXT : 0));
+    void *prefix = NULL;
+
 #ifdef OPENSSL_SYS_VMS
     if (istext(format))
         b = BIO_push(BIO_new(BIO_f_linebuffer()), b);
 #endif
+
+    if (istext(format) && (prefix = getenv("HARNESS_OSSL_PREFIX")) != NULL) {
+        if (prefix_method == NULL)
+            prefix_method = apps_bf_prefix();
+        b = BIO_push(BIO_new(prefix_method), b);
+        BIO_ctrl(b, PREFIX_CTRL_SET_PREFIX, 0, prefix);
+    }
+
     return b;
 }
 
@@ -2450,6 +2462,12 @@ BIO *dup_bio_err(int format)
     return b;
 }
 
+void destroy_prefix_method()
+{
+    BIO_meth_free(prefix_method);
+    prefix_method = NULL;
+}
+
 void unbuffer(FILE *fp)
 {
 /*

apps/apps.h

@@ -55,6 +55,12 @@ BIO_METHOD *apps_bf_prefix(void);
  * remains unlikely for the foreseeable future and beyond.
  */
 #define PREFIX_CTRL_SET_PREFIX  (1 << 15)
+/*
+ * apps_bf_prefix() returns a dynamically created BIO_METHOD, which we
+ * need to destroy at some point.  When created internally, it's stored
+ * in an internal pointer which can be freed with the following function
+ */
+void destroy_prefix_method(void);
 
 BIO *dup_bio_in(int format);
 BIO *dup_bio_out(int format);

apps/openssl.c

@@ -93,6 +93,7 @@ static int apps_startup()
 static void apps_shutdown()
 {
     destroy_ui_method();
+    destroy_prefix_method();
 }
 
 static char *make_config_name()

util/perl/OpenSSL/Test.pm

-# Copyright 2016 The OpenSSL Project Authors. All Rights Reserved.
+# Copyright 2016-2018 The OpenSSL Project Authors. All Rights Reserved.
 #
 # Licensed under the OpenSSL license (the "License").  You may not use
 # this file except in compliance with the License.  You can obtain a copy
@@ -476,7 +476,9 @@ sub run {
 	}
 	close $pipe;
     } else {
+	$ENV{HARNESS_OSSL_PREFIX} = "# ";
 	system("$prefix$cmd");
+	delete $ENV{HARNESS_OSSL_PREFIX};
     }
     $e = ($? & 0x7f) ? ($? & 0x7f)|0x80 : ($? >> 8);
     $r = $hooks{exit_checker}->($e);