Merge pull request ethereum#2353 from ethereum/license_output

Include license and warranty statement with solc.

CMakeLists.txt

@@ -24,6 +24,10 @@ include(EthExecutableHelper)
 # Include utils
 include(EthUtils)
 
+# Create license.h from LICENSE.txt and template
+file(READ ${CMAKE_SOURCE_DIR}/LICENSE.txt LICENSE_TEXT)
+configure_file("${CMAKE_SOURCE_DIR}/cmake/templates/license.h.in" "license.h")
+
 include(EthOptions)
 configure_project(TESTS)
 

cmake/templates/license.h.in

@@ -0,0 +1,3 @@
+#pragma once
+
+static char const* licenseText = R"(@LICENSE_TEXT@)";

solc/CommandLineInterface.cpp

@@ -23,6 +23,7 @@
 #include "CommandLineInterface.h"
 
 #include "solidity/BuildInfo.h"
+#include "license.h"
 
 #include <libsolidity/interface/Version.h>
 #include <libsolidity/parsing/Scanner.h>
@@ -94,6 +95,7 @@ static string const g_strHelp = "help";
 static string const g_strInputFile = "input-file";
 static string const g_strInterface = "interface";
 static string const g_strJulia = "julia";
+static string const g_strLicense = "license";
 static string const g_strLibraries = "libraries";
 static string const g_strLink = "link";
 static string const g_strMetadata = "metadata";
@@ -186,6 +188,13 @@ static void version()
 	exit(0);
 }
 
+static void license()
+{
+	// This is a static variable generated by cmake from LICENSE.txt
+	cout << licenseText << endl;
+	exit(0);
+}
+
 static bool needsHumanTargetedStdout(po::variables_map const& _args)
 {
 	if (_args.count(g_argGas))
@@ -510,8 +519,12 @@ void CommandLineInterface::createFile(string const& _fileName, string const& _da
 bool CommandLineInterface::parseArguments(int _argc, char** _argv)
 {
 	// Declare the supported options.
-	po::options_description desc(
-		R"(solc, the Solidity commandline compiler.
+	po::options_description desc(R"(solc, the Solidity commandline compiler.
+
+This program comes with ABSOLUTELY NO WARRANTY. This is free software, and you
+are welcome to redistribute it under certain conditions. See 'solc --license'
+for details.
+
 Usage: solc [options] [input_file...]
 Compiles the given Solidity input files (or the standard input if none given or
 "-" is used as a file name) and outputs the components specified in the options
@@ -523,10 +536,12 @@ remap paths using the context:prefix=path syntax.
 
 Allowed options)",
 		po::options_description::m_default_line_length,
-		po::options_description::m_default_line_length - 23);
+		po::options_description::m_default_line_length - 23
+	);
 	desc.add_options()
 		(g_argHelp.c_str(), "Show help message and exit.")
 		(g_argVersion.c_str(), "Show version and exit.")
+		(g_strLicense.c_str(), "Show licensing information and exit.")
 		(g_argOptimize.c_str(), "Enable bytecode optimizer.")
 		(
 			g_argOptimizeRuns.c_str(),
@@ -633,6 +648,12 @@ Allowed options)",
 		return false;
 	}
 
+	if (m_args.count(g_strLicense))
+	{
+		license();
+		return false;
+	}
+
 	if (m_args.count(g_argCombinedJson))
 	{
 		vector<string> requests;