From 1f4784a9ee5d38364aa7f0d8f91a22069b73a6ae Mon Sep 17 00:00:00 2001
From: Ian Lynagh <igloo@earth.li>
Date: Sun, 15 Apr 2007 16:23:15 +0000
Subject: [PATCH] Implement ifBuildable ifBuildable only runs a command it is
 given if the library in . either must be built
 (core-package - readline) or is buildable.

---
 libraries/Makefile       |   27 +++++++++++++++++++--------
 libraries/ifBuildable.hs |   41 +++++++++++++++++++++++++++++++++++++++++
 2 files changed, 60 insertions(+), 8 deletions(-)
 create mode 100644 libraries/ifBuildable.hs

diff --git a/libraries/Makefile b/libraries/Makefile
index ff20ce3..fe89436 100644
--- a/libraries/Makefile
+++ b/libraries/Makefile
@@ -82,7 +82,8 @@ subdirs:
 
 .PHONY: boot
 
-boot: $(foreach SUBDIR,$(SUBDIRS),$(SUBDIR)/setup/Setup)
+boot: ifBuildable/ifBuildable \
+	  $(foreach SUBDIR,$(SUBDIRS),$(SUBDIR)/setup/Setup)
 	# XXX Hideous hacks:
 	$(GENPRIMOP) --make-haskell-source < ../compiler/prelude/primops.txt > base/GHC/Prim.hs
 	$(GENPRIMOP) --make-haskell-wrappers < ../compiler/prelude/primops.txt > base/GHC/PrimopWrappers.hs
@@ -100,6 +101,13 @@ $(foreach SUBDIR,$(SUBDIRS),$(SUBDIR)/setup/Setup): \
 	$(CP) $*/Setup.*hs $*/setup
 	cd $*/setup && $(GHC) -Wall --make -i../../$(BOOTSTRAPPING_CABAL) Setup.*hs -o Setup
 
+ifBuildable/ifBuildable: ifBuildable.hs stamp/$(BOOTSTRAPPING_CABAL)
+	-$(RM) -rf ifBuildable
+	mkdir ifBuildable
+	$(CP) ifBuildable.hs ifBuildable/
+	cd ifBuildable && $(GHC) -Wall --make -i../$(BOOTSTRAPPING_CABAL) \
+	                         ifBuildable -o ifBuildable
+
 stamp/$(BOOTSTRAPPING_CABAL):
 	$(RM) -rf $(BOOTSTRAPPING_CABAL)
 	$(CP) -R Cabal $(BOOTSTRAPPING_CABAL)
@@ -143,8 +151,9 @@ stamp/configure.library.build$(CONFIGURE_STAMP_EXTRAS).%: %/setup/Setup
 $(foreach SUBDIR,$(SUBDIRS),build.library.$(SUBDIR)):\
 build.library.%: stamp/configure.library.build$(CONFIGURE_STAMP_EXTRAS).% \
                  %/setup/Setup
-	cd $* && setup/Setup build $(addprefix --ghc-option=,$(GhcLibHcOpts))
-	cd $* && setup/Setup register --inplace
+	cd $* && ../ifBuildable/ifBuildable setup/Setup build \
+	                                $(addprefix --ghc-option=,$(GhcLibHcOpts))
+	cd $* && ../ifBuildable/ifBuildable setup/Setup register --inplace
 
 .PHONY: doc
 
@@ -180,22 +189,24 @@ install-docs:
 $(foreach SUBDIR,$(SUBDIRS),stamp/configure.library.install.$(SUBDIR)): \
 stamp/configure.library.install.%: %/setup/Setup
 	-$(RM) -f stamp/configure.library.*.$*
-	cd $* && setup/Setup configure $(CONFIGURE_OPTS) \
-	                               --prefix=$(prefix) \
-	                               --with-compiler=$(bindir)/ghc \
-	                               --datasubdir=ghc
+	cd $* && ../ifBuildable/ifBuildable setup/Setup configure \
+	                                    $(CONFIGURE_OPTS) \
+	                                    --prefix=$(prefix) \
+	                                    --with-compiler=$(bindir)/ghc \
+	                                    --datasubdir=ghc
 	touch $@
 
 # We need to reconfigure as we now need to register with the normal ghc-pkg
 $(foreach SUBDIR,$(SUBDIRS),install.library.$(SUBDIR)): \
 install.library.%: stamp/configure.library.install.% %/setup/Setup
-	cd $* && setup/Setup install
+	cd $* && ../ifBuildable/ifBuildable setup/Setup install
 
 .PHONY: clean clean.library.%
 
 clean: $(foreach SUBDIR,$(SUBDIRS),clean.library.$(SUBDIR))
 	$(RM) -f stamp/$(BOOTSTRAPPING_CABAL)
 	$(RM) -rf $(BOOTSTRAPPING_CABAL)
+	$(RM) -rf ifBuildable
 	$(RM) -f libraries.txt index.html doc-index.html
 
 $(foreach SUBDIR,$(SUBDIRS),clean.library.$(SUBDIR)): \
diff --git a/libraries/ifBuildable.hs b/libraries/ifBuildable.hs
new file mode 100644
index 0000000..c60e108
--- /dev/null
+++ b/libraries/ifBuildable.hs
@@ -0,0 +1,41 @@
+
+module Main (main) where
+
+import Control.Monad
+import Data.Maybe
+import Distribution.PackageDescription
+import Distribution.Simple
+import Distribution.Simple.Utils
+import System.Cmd
+import System.Environment
+import System.Exit
+
+main :: IO ()
+main = do let verbosity = 0
+          mustBeBuildables <- getMustBeBuildablePackages
+          dfd <- defaultPackageDesc verbosity
+          pkgDescr <- readPackageDescription verbosity dfd
+          mInfolFile <- defaultHookedPackageDesc
+          info <- case mInfolFile of
+                      Nothing -> return emptyHookedBuildInfo
+                      Just infoFile -> readHookedBuildInfo verbosity infoFile
+          let pkgDescr' = updatePackageDescription info pkgDescr
+              pkg = pkgName (package pkgDescr')
+              mustBeBuildable = pkg `elem` mustBeBuildables
+              buildInfos = map libBuildInfo (maybeToList (library pkgDescr'))
+                        ++ map buildInfo (executables pkgDescr')
+              isBuildable = any buildable buildInfos
+          when (mustBeBuildable || isBuildable) $ do
+              args <- getArgs
+              case args of
+                  prog : progArgs ->
+                      do ec <- rawSystem prog progArgs
+                         exitWith ec
+                  [] ->
+                      error "ifBuildable: No command given"
+
+getMustBeBuildablePackages :: IO [String]
+getMustBeBuildablePackages
+ = do xs <- readFile "../core-packages"
+      return $ filter ("readline" /=) $ lines xs
+
-- 
1.7.10.4