From a467d0c92dcc6107eacfdf36d541a71b7c2ffe7b Mon Sep 17 00:00:00 2001
From: Jon Siwek <jsiwek@corelight.com>
Date: Fri, 31 Aug 2018 09:24:03 -0500
Subject: [PATCH] Add @deprecated directive

It emits a warning stating that the script is deprecated.
---
 doc/script-reference/directives.rst             | 10 ++++++++++
 src/scan.l                                      | 17 +++++++++++++++++
 .../Baseline/language.at-deprecated/.stderr     |  3 +++
 testing/btest/language/at-deprecated.bro        | 16 ++++++++++++++++
 4 files changed, 46 insertions(+)
 create mode 100644 testing/btest/Baseline/language.at-deprecated/.stderr
 create mode 100644 testing/btest/language/at-deprecated.bro

diff --git a/doc/script-reference/directives.rst b/doc/script-reference/directives.rst
index b56967ff3d..e515cf8bdb 100644
--- a/doc/script-reference/directives.rst
+++ b/doc/script-reference/directives.rst
@@ -27,6 +27,16 @@ executed.  Directives are evaluated before script execution begins.
 
         print "File:", @FILENAME;
 
+.. bro:keyword:: @deprecated
+
+    Marks the current script as deprecated. This can be placed anywhere in
+    the script, but a good convention is to put it as the first line.
+    You can also supply additional comments.
+
+    Example::
+
+        @deprecated "Use '@load foo' instead"
+
 .. bro:keyword:: @load
 
     Loads the specified Bro script, specified as the relative pathname
diff --git a/src/scan.l b/src/scan.l
index ffdec4d640..9e0e5f75fc 100644
--- a/src/scan.l
+++ b/src/scan.l
@@ -315,6 +315,23 @@ when	return TOK_WHEN;
 	return TOK_ATTR_SYNCHRONIZED;
 	}
 
+@deprecated.* {
+	auto num_files = file_stack.length();
+	auto comment = skip_whitespace(yytext + 11);
+
+	if ( num_files > 0 )
+		{
+		auto lf = file_stack[num_files - 1];
+
+		if ( lf->name )
+			reporter->Warning("deprecated script loaded from %s:%d %s",
+			                  lf->name, lf->line, comment);
+		else
+			reporter->Warning("deprecated script loaded from command line arguments %s", comment);
+		}
+	else
+		reporter->Warning("deprecated script loaded %s", comment);
+	}
 
 @DEBUG	return TOK_DEBUG;	// marks input for debugger
 
diff --git a/testing/btest/Baseline/language.at-deprecated/.stderr b/testing/btest/Baseline/language.at-deprecated/.stderr
new file mode 100644
index 0000000000..4668f2d7bf
--- /dev/null
+++ b/testing/btest/Baseline/language.at-deprecated/.stderr
@@ -0,0 +1,3 @@
+warning in ./foo.bro, line 1: deprecated script loaded from command line arguments 
+warning in ./bar.bro, line 1: deprecated script loaded from ./foo.bro:2 "Use '@load qux.bro' instead"
+warning in ./baz.bro, line 1: deprecated script loaded from ./foo.bro:3 
diff --git a/testing/btest/language/at-deprecated.bro b/testing/btest/language/at-deprecated.bro
new file mode 100644
index 0000000000..dd0f746658
--- /dev/null
+++ b/testing/btest/language/at-deprecated.bro
@@ -0,0 +1,16 @@
+# @TEST-EXEC: bro -b foo
+# @TEST-EXEC: TEST_DIFF_CANONIFIER=$SCRIPTS/diff-remove-abspath btest-diff .stderr
+
+@TEST-START-FILE foo.bro
+@deprecated
+@load bar
+@load baz
+@TEST-END-FILE
+
+@TEST-START-FILE bar.bro
+@deprecated "Use '@load qux.bro' instead"
+@TEST-END-FILE
+
+@TEST-START-FILE baz.bro
+@deprecated
+@TEST-END-FILE