Add JSON cmdline interface

allows reading the command line in JSON format
from stdin.

Author: peterschrammel

src/json/Makefile

@@ -1,4 +1,5 @@
-SRC = json_lex.yy.cpp \
+SRC = json_interface.cpp \
+      json_lex.yy.cpp \
       json_parser.cpp \
       json_y.tab.cpp \
       # Empty last line

src/json/json_interface.cpp

@@ -0,0 +1,120 @@
+/*******************************************************************\
+
+Module: JSON Commandline Interface
+
+Author: Peter Schrammel
+
+\*******************************************************************/
+
+/// \file
+/// JSON Commandline Interface
+
+#include "json_interface.h"
+
+#include <util/cmdline.h>
+#include <util/exception_utils.h>
+#include <util/json.h>
+#include <util/message.h>
+
+#include "json_parser.h"
+
+#include <iostream>
+
+/// Parse commandline options from \p json into \p cmdline
+static void get_json_options(const json_objectt &json, cmdlinet &cmdline)
+{
+  const jsont &arguments = json["arguments"];
+  if(!arguments.is_array())
+  {
+    throw invalid_command_line_argument_exceptiont(
+      "array expected", "'arguments'");
+  }
+
+  for(const auto &argument : to_json_array(arguments))
+  {
+    if(!argument.is_string())
+    {
+      throw invalid_command_line_argument_exceptiont(
+        "string expected", "argument");
+    }
+
+    cmdline.args.push_back(argument.value);
+  }
+
+  const jsont &options = json["options"];
+  if(!options.is_object())
+  {
+    throw invalid_command_line_argument_exceptiont(
+      "array expected", "'options'");
+  }
+
+  for(const auto &option_pair : to_json_object(options))
+  {
+    if(option_pair.second.is_string() || option_pair.second.is_number())
+    {
+      // e.g. --option x
+      cmdline.set(option_pair.first, option_pair.second.value);
+    }
+    else if(option_pair.second.is_boolean())
+    {
+      // e.g. --flag
+      if(option_pair.second.is_true())
+        cmdline.set(option_pair.first);
+    }
+    else if(option_pair.second.is_array())
+    {
+      // e.g. --option x --option y
+      for(const auto &element : to_json_array(option_pair.second))
+      {
+        if(element.is_string())
+          cmdline.set(option_pair.first, element.value);
+        else
+        {
+          throw invalid_command_line_argument_exceptiont(
+            "string expected", option_pair.first);
+        }
+      }
+    }
+    else
+    {
+      throw invalid_command_line_argument_exceptiont(
+        "unrecognized commandline option format",
+        option_pair.first,
+        "Boolean, string, number, or string array expected");
+    }
+  }
+}
+
+void json_interface(cmdlinet &cmdline, message_handlert &message_handler)
+{
+  if(cmdline.isset("json-interface"))
+  {
+    jsont json;
+
+    parse_json(std::cin, "", message_handler, json);
+
+    try
+    {
+      if(!json.is_object())
+      {
+        throw invalid_command_line_argument_exceptiont(
+          "JSON object expected at top-level", "command-line JSON input");
+      }
+
+      get_json_options(to_json_object(json), cmdline);
+
+      // Add this so that it gets propagated into optionst;
+      // the ui_message_handlert::uit has already been set on the basis
+      // of the json-interface flag.
+      cmdline.set("json-ui");
+    }
+    catch(const invalid_command_line_argument_exceptiont &e)
+    {
+      messaget log(message_handler);
+      log.error() << e.what() << messaget::eom;
+
+      // make sure we fail with a usage error
+      cmdline.clear();
+    }
+  }
+}

src/json/json_interface.h

@@ -0,0 +1,40 @@
+/*******************************************************************\
+
+Module: JSON Commandline Interface
+
+Author: Peter Schrammel
+
+\*******************************************************************/
+
+/// \file
+/// JSON Commandline Interface
+
+#ifndef CPROVER_JSON_JSON_INTERFACE_H
+#define CPROVER_JSON_JSON_INTERFACE_H
+
+class cmdlinet;
+class message_handlert;
+
+/// Parses the JSON-formatted command line from stdin
+///
+/// Example:
+/// \code{.json}
+/// {
+///   "arguments": [
+///     "main.c"
+///   ],
+///   "options": {
+///     "function": "foo",
+///     "unwind": 3,
+///     "property": [
+///       "foo.assertion.1",
+///       "foo.assertion.3"
+///     ],
+///     "trace": true,
+///     "show-properties": false
+///   }
+/// }
+/// \endcode
+void json_interface(cmdlinet &, message_handlert &);
+
+#endif // CPROVER_JSON_JSON_INTERFACE_H