From 93b1df695ed9d38294e873dacb3721cf19e94086 Mon Sep 17 00:00:00 2001
From: Rob Dockins <rdockins@galois.com>
Date: Tue, 21 Sep 2021 14:12:22 -0700
Subject: [PATCH] Add a `cSettingOutputDirectory` setting for codegen.

If set, this option defines an output destination directory
for generated files.  It will be created if necessary.

Fixes #255
---
 .../src/Copilot/Compile/C99/Compile/Internal.hs      | 12 ++++++++++--
 .../src/Copilot/Compile/C99/Settings/Internal.hs     |  3 ++-
 2 files changed, 12 insertions(+), 3 deletions(-)

diff --git a/copilot-c99/src/Copilot/Compile/C99/Compile/Internal.hs b/copilot-c99/src/Copilot/Compile/C99/Compile/Internal.hs
index 8a07d4dd..b153cdfb 100644
--- a/copilot-c99/src/Copilot/Compile/C99/Compile/Internal.hs
+++ b/copilot-c99/src/Copilot/Compile/C99/Compile/Internal.hs
@@ -7,6 +7,8 @@ module Copilot.Compile.C99.Compile.Internal
 import Text.PrettyPrint     (render)
 import Data.List            (nub)
 import Data.Maybe           (catMaybes)
+import System.Directory     (createDirectoryIfMissing)
+import System.FilePath      ((</>))
 
 import Language.C99.Pretty  (pretty)
 import qualified Language.C99.Simple as C
@@ -41,8 +43,14 @@ compileWith cSettings prefix spec = do
                         , ""
                         ]
 
-  writeFile (prefix ++ ".c") $ cmacros ++ cfile
-  writeFile (prefix ++ ".h") hfile
+  case cSettingsOutputDirectory cSettings of
+    Nothing ->
+      do writeFile (prefix ++ ".c") $ cmacros ++ cfile
+         writeFile (prefix ++ ".h") hfile
+    Just dir ->
+      do createDirectoryIfMissing True dir
+         writeFile (dir </> prefix ++ ".c") $ cmacros ++ cfile
+         writeFile (dir </> prefix ++ ".h") hfile
 
 -- | Compile a specification to a .h and a .c file.
 --
diff --git a/copilot-c99/src/Copilot/Compile/C99/Settings/Internal.hs b/copilot-c99/src/Copilot/Compile/C99/Settings/Internal.hs
index 90791a19..cf4b08b9 100644
--- a/copilot-c99/src/Copilot/Compile/C99/Settings/Internal.hs
+++ b/copilot-c99/src/Copilot/Compile/C99/Settings/Internal.hs
@@ -4,8 +4,9 @@ module Copilot.Compile.C99.Settings.Internal where
 -- | Settings used to customize the code generated.
 data CSettings = CSettings
   { cSettingsStepFunctionName :: String
+  , cSettingsOutputDirectory :: Maybe FilePath
   }
 
 -- | Default settings with a step function called @step@.
 mkDefaultCSettings :: CSettings
-mkDefaultCSettings = CSettings "step"
+mkDefaultCSettings = CSettings "step" Nothing