C#: Migrate extractor to this repository.

csharp/extractor/Semmle.Extraction.CSharp/Options.cs

@@ -0,0 +1,87 @@
+using System;
+using System.Collections.Generic;
+using Semmle.Util;
+
+namespace Semmle.Extraction.CSharp
+{
+    public sealed class Options : CommonOptions
+    {
+        /// <summary>
+        /// The compiler exe, or null if unspecified.
+        /// </summary>
+        public string CompilerName;
+
+        /// <summary>
+        /// Specified .Net Framework dir, or null if unspecified.
+        /// </summary>
+        public string Framework;
+
+        /// <summary>
+        /// All other arguments passed to the compilation.
+        /// </summary>
+        public IList<string> CompilerArguments = new List<string>();
+
+        /// <summary>
+        /// Holds if the extractor was launched from the CLR tracer.
+        /// </summary>
+        public bool ClrTracer = false;
+
+        public static Options CreateWithEnvironment(string[] arguments)
+        {
+            var options = new Options();
+            var extractionOptions = Environment.GetEnvironmentVariable("SEMMLE_EXTRACTOR_OPTIONS") ??
+                Environment.GetEnvironmentVariable("LGTM_INDEX_EXTRACTOR");
+
+            var argsList = new List<string>(arguments);
+
+            if (!string.IsNullOrEmpty(extractionOptions))
+                argsList.AddRange(extractionOptions.Split(' '));
+
+            options.ParseArguments(argsList);
+            return options;
+        }
+
+        public override bool handleArgument(string argument)
+        {
+            CompilerArguments.Add(argument);
+            return true;
+        }
+
+        public override void invalidArgument(string argument)
+        {
+            // Unrecognised arguments are passed to the compiler.
+            CompilerArguments.Add(argument);
+        }
+
+        public override bool handleOption(string key, string value)
+        {
+            switch (key)
+            {
+                case "compiler":
+                    CompilerName = value;
+                    return true;
+                case "framework":
+                    Framework = value;
+                    return true;
+                default:
+                    return base.handleOption(key, value);
+            }
+        }
+
+        public override bool handleFlag(string flag, bool value)
+        {
+            switch (flag)
+            {
+                case "clrtracer":
+                    ClrTracer = value;
+                    return true;
+                default:
+                    return base.handleFlag(flag, value);
+            }
+        }
+
+        private Options()
+        {
+        }
+    }
+}