\begin{code}
module Finder (
- Finder, -- = ModuleName -> IO (Maybe (Module, ModuleLocation))
- newFinder, -- :: PackageConfigInfo -> IO Finder,
- ModuleLocation(..),
- mkHomeModuleLocn
+ flushFinderCache, -- :: IO ()
+ FindResult(..),
+ findModule, -- :: ModuleName -> Bool -> IO FindResult
+ findPackageModule, -- :: ModuleName -> Bool -> IO FindResult
+ mkHomeModLocation, -- :: ModuleName -> FilePath -> IO ModLocation
+ mkHomeModLocation2, -- :: ModuleName -> FilePath -> String -> IO ModLocation
+ addHomeModuleToFinder, -- :: HscEnv -> Module -> ModLocation -> IO ()
+
+ findLinkable, -- :: ModuleName -> ModLocation -> IO (Maybe Linkable)
+
+ cantFindError, -- :: DynFlags -> Module -> FindResult -> SDoc
) where
#include "HsVersions.h"
-import CmStaticInfo
-import DriverPhases
-import DriverState
import Module
-import FiniteMap
+import UniqFM ( filterUFM )
+import HscTypes
+import Packages
+import FastString
import Util
-import Panic
-
-import IOExts
-import Directory
-import List
-import IO
-import Monad
-\end{code}
-
-The Finder provides a thin filesystem abstraction to the rest of the
-compiler. For a given module, it knows (a) which package the module
-lives in, so it can make a Module from a ModuleName, and (b) where the
-source, interface, and object files for a module live.
-
-\begin{code}
-type Finder = ModuleName -> IO (Maybe (Module, ModuleLocation))
-
--- For a module in another package, the hs_file and obj_file
--- components of ModuleLocation are undefined.
-
--- The locations specified by a ModuleLocation may or may not
--- correspond to actual files yet: for example, even if the object
--- file doesn't exist, the ModuleLocation still contains the path to
--- where the object file will reside if/when it is created.
-
-data ModuleLocation
- = ModuleLocation {
- hs_file :: FilePath,
- hi_file :: FilePath,
- obj_file :: FilePath
- }
-
--- caches contents of package directories, never expunged
-GLOBAL_VAR(pkgDirCache, Nothing, Maybe (FiniteMap String (PackageName, FilePath)))
-
--- caches contents of home directories, expunged whenever we
--- create a new finder.
-GLOBAL_VAR(homeDirCache, emptyFM, FiniteMap String FilePath)
-
--- caches finder mapping, expunged whenever we create a new finder.
-GLOBAL_VAR(finderMapCache, emptyFM, FiniteMap ModuleName Module)
-
-
-newFinder :: PackageConfigInfo -> IO Finder
-newFinder (PackageConfigInfo pkgs) = do
- -- expunge our caches
- writeIORef homeDirCache emptyFM
- writeIORef finderMapCache emptyFM
-
- -- populate the home dir cache, using the import path (the import path
- -- is changed by -i flags on the command line, and defaults to ["."]).
- home_imports <- readIORef import_paths
- let extendFM fm path = do
- contents <- getDirectoryContents' path
- return (addListToFM fm (zip contents (repeat path)))
- home_map <- foldM extendFM emptyFM home_imports
- writeIORef homeDirCache home_map
-
- -- populate the package cache, if necessary
- pkg_cache <- readIORef pkgDirCache
- case pkg_cache of
- Nothing -> do
-
- let extendFM fm pkg = do
- let dirs = import_dirs pkg
- pkg_name = _PK_ (name pkg)
- let addDir fm dir = do
- contents <- getDirectoryContents' dir
- return (addListToFM fm (zip contents
- (repeat (pkg_name,dir))))
- foldM addDir fm dirs
-
- pkg_map <- foldM extendFM emptyFM pkgs
- writeIORef pkgDirCache (Just pkg_map)
-
- Just _ ->
- return ()
-
- -- and return the finder
- return finder
-
+import DynFlags ( DynFlags(..), isOneShot, GhcMode(..) )
+import Outputable
+
+import DATA_IOREF ( IORef, writeIORef, readIORef )
+
+import Data.List
+import System.Directory
+import System.IO
+import Control.Monad
+import Maybes ( MaybeErr(..) )
+import Data.Maybe ( isNothing )
+
+
+type FileExt = String -- Filename extension
+type BaseName = String -- Basename of file
+
+-- -----------------------------------------------------------------------------
+-- The Finder
+
+-- The Finder provides a thin filesystem abstraction to the rest of
+-- the compiler. For a given module, it can tell you where the
+-- source, interface, and object files for that module live.
+
+-- It does *not* know which particular package a module lives in. Use
+-- Packages.moduleToPackageConfig for that.
+
+-- -----------------------------------------------------------------------------
+-- The finder's cache
+
+-- remove all the home modules from the cache; package modules are
+-- assumed to not move around during a session.
+flushFinderCache :: IORef FinderCache -> IO ()
+flushFinderCache finder_cache = do
+ fm <- readIORef finder_cache
+ writeIORef finder_cache $! filterUFM (\(loc,m) -> isNothing m) fm
+
+addToFinderCache :: IORef FinderCache -> Module -> FinderCacheEntry -> IO ()
+addToFinderCache finder_cache mod_name entry = do
+ fm <- readIORef finder_cache
+ writeIORef finder_cache $! extendModuleEnv fm mod_name entry
+
+lookupFinderCache :: IORef FinderCache -> Module -> IO (Maybe FinderCacheEntry)
+lookupFinderCache finder_cache mod_name = do
+ fm <- readIORef finder_cache
+ return $! lookupModuleEnv fm mod_name
+
+-- -----------------------------------------------------------------------------
+-- Locating modules
+
+-- This is the main interface to the finder, which maps ModuleNames to
+-- Modules and ModLocations.
+--
+-- The Module contains one crucial bit of information about a module:
+-- whether it lives in the current ("home") package or not (see Module
+-- for more details).
+--
+-- The ModLocation contains the names of all the files associated with
+-- that module: its source file, .hi file, object file, etc.
+
+data FindResult
+ = Found ModLocation PackageIdH
+ -- the module was found
+ | PackageHidden PackageId
+ -- for an explicit source import: the package containing the module is
+ -- not exposed.
+ | ModuleHidden PackageId
+ -- for an explicit source import: the package containing the module is
+ -- exposed, but the module itself is hidden.
+ | NotFound [FilePath]
+ -- the module was not found, the specified places were searched.
+
+type LocalFindResult = MaybeErr [FilePath] FinderCacheEntry
+ -- LocalFindResult is used for internal functions which
+ -- return a more informative type; it's munged into
+ -- the external FindResult by 'cached'
+
+cached :: Bool
+ -> (DynFlags -> Module -> IO LocalFindResult)
+ -> HscEnv -> Module -> Bool -> IO FindResult
+cached home_allowed wrapped_fn hsc_env name explicit
+ = do { -- First try the cache
+ let cache = hsc_FC hsc_env
+ ; mb_entry <- lookupFinderCache cache name
+ ; case mb_entry of {
+ Just old_entry -> return (found old_entry) ;
+ Nothing -> do
+
+ { -- Now try the wrapped function
+ mb_entry <- wrapped_fn (hsc_dflags hsc_env) name
+ ; case mb_entry of
+ Failed paths -> return (NotFound paths)
+ Succeeded new_entry -> do { addToFinderCache cache name new_entry
+ ; return (found new_entry) }
+ }}}
+ where
+ -- We've found the module, so the remaining question is
+ -- whether it's visible or not
+ found :: FinderCacheEntry -> FindResult
+ found (loc, Nothing)
+ | home_allowed = Found loc HomePackage
+ | otherwise = NotFound []
+ found (loc, Just (pkg, exposed_mod))
+ | explicit && not exposed_mod = ModuleHidden pkg_name
+ | explicit && not (exposed pkg) = PackageHidden pkg_name
+ | otherwise = Found loc (ExtPackage (mkPackageId (package pkg)))
+ where
+ pkg_name = packageConfigId pkg
+
+addHomeModuleToFinder :: HscEnv -> Module -> ModLocation -> IO ()
+addHomeModuleToFinder hsc_env mod loc
+ = addToFinderCache (hsc_FC hsc_env) mod (loc, Nothing)
+
+
+-- -----------------------------------------------------------------------------
+-- The two external entry points
+
+
+findModule :: HscEnv -> Module -> Bool -> IO FindResult
+findModule = cached True findModule'
-finder :: ModuleName -> IO (Maybe (Module, ModuleLocation))
-finder name = do
- j <- maybeHomeModule name
- case j of
- Just home_module -> return (Just home_module)
- Nothing -> maybePackageModule name
-
-maybeHomeModule :: ModuleName -> IO (Maybe (Module, ModuleLocation))
-maybeHomeModule mod_name = do
- home_cache <- readIORef homeDirCache
-
- let basename = moduleNameString mod_name
- hs = basename ++ ".hs"
- lhs = basename ++ ".lhs"
-
- case lookupFM home_cache hs of {
- Just path -> mkHomeModuleLocn mod_name (path ++ '/':basename) hs;
- Nothing ->
-
- case lookupFM home_cache lhs of {
- Just path -> mkHomeModuleLocn mod_name (path ++ '/':basename) lhs;
- Nothing -> return Nothing
-
- }}
-
-mkHomeModuleLocn mod_name basename source_fn = do
-
- -- figure out the .hi file name: it lives in the same dir as the
- -- source, unless there's a -ohi flag on the command line.
- ohi <- readIORef output_hi
- hisuf <- readIORef hi_suf
- let hifile = case ohi of
- Nothing -> basename ++ hisuf
- Just fn -> fn
-
- -- figure out the .o file name. It also lives in the same dir
- -- as the source, but can be overriden by a -odir flag.
- o_file <- odir_ify (basename ++ '.':phaseInputExt Ln)
-
- return (Just (mkHomeModule mod_name,
- ModuleLocation{
- hs_file = source_fn,
- hi_file = hifile,
- obj_file = o_file
- }
- ))
-
-maybePackageModule :: ModuleName -> IO (Maybe (Module, ModuleLocation))
-maybePackageModule mod_name = do
- maybe_pkg_cache <- readIORef pkgDirCache
- case maybe_pkg_cache of {
- Nothing -> panic "maybePackageModule: no pkg_cache";
- Just pkg_cache -> do
-
- -- hi-suffix for packages depends on the build tag.
- package_hisuf <-
- do tag <- readIORef build_tag
- if null tag
- then return "hi"
- else return (tag ++ "_hi")
-
- let basename = moduleNameString mod_name
- hi = basename ++ '.':package_hisuf
-
- case lookupFM pkg_cache hi of
- Nothing -> return Nothing
- Just (pkg_name,path) ->
- return (Just (mkModule mod_name pkg_name,
- ModuleLocation{
- hs_file = error "package module; no source",
- hi_file = hi,
- obj_file = error "package module; no object"
- }
- ))
-
- }
-
-getDirectoryContents' d
- = IO.catch (getDirectoryContents d)
- (\_ -> do hPutStr stderr
- ("WARNING: error while reading directory " ++ d)
- return []
- )
-
+findPackageModule :: HscEnv -> Module -> Bool -> IO FindResult
+findPackageModule = cached False findPackageModule'
+
+-- -----------------------------------------------------------------------------
+-- The internal workers
+
+findModule' :: DynFlags -> Module -> IO LocalFindResult
+-- Find home or package module
+findModule' dflags name = do
+ r <- findPackageModule' dflags name
+ case r of
+ Failed pkg_files -> do
+ j <- findHomeModule' dflags name
+ case j of
+ Failed home_files ->
+ return (Failed (home_files ++ pkg_files))
+ other_result
+ -> return other_result
+ other_result
+ -> return other_result
+
+findHomeModule' :: DynFlags -> Module -> IO LocalFindResult
+findHomeModule' dflags mod = do
+ let home_path = importPaths dflags
+ hisuf = hiSuf dflags
+
+ let
+ source_exts =
+ [ ("hs", mkHomeModLocationSearched dflags mod "hs")
+ , ("lhs", mkHomeModLocationSearched dflags mod "lhs")
+ ]
+
+ hi_exts = [ (hisuf, mkHiOnlyModLocation dflags hisuf)
+ , (addBootSuffix hisuf, mkHiOnlyModLocation dflags hisuf)
+ ]
+
+ -- In compilation manager modes, we look for source files in the home
+ -- package because we can compile these automatically. In one-shot
+ -- compilation mode we look for .hi and .hi-boot files only.
+ exts | isOneShot (ghcMode dflags) = hi_exts
+ | otherwise = source_exts
+
+ searchPathExts home_path mod exts
+
+findPackageModule' :: DynFlags -> Module -> IO LocalFindResult
+findPackageModule' dflags mod
+ = case moduleToPackageConfig dflags mod of
+ Nothing -> return (Failed [])
+ Just pkg_info -> findPackageIface dflags mod pkg_info
+
+findPackageIface :: DynFlags -> Module -> (PackageConfig,Bool) -> IO LocalFindResult
+findPackageIface dflags mod pkg_info@(pkg_conf, _) = do
+ let
+ tag = buildTag dflags
+
+ -- hi-suffix for packages depends on the build tag.
+ package_hisuf | null tag = "hi"
+ | otherwise = tag ++ "_hi"
+ hi_exts =
+ [ (package_hisuf,
+ mkPackageModLocation dflags pkg_info package_hisuf) ]
+
+ source_exts =
+ [ ("hs", mkPackageModLocation dflags pkg_info package_hisuf)
+ , ("lhs", mkPackageModLocation dflags pkg_info package_hisuf)
+ ]
+
+ -- mkdependHS needs to look for source files in packages too, so
+ -- that we can make dependencies between package before they have
+ -- been built.
+ exts
+ | MkDepend <- ghcMode dflags = hi_exts ++ source_exts
+ | otherwise = hi_exts
+ -- we never look for a .hi-boot file in an external package;
+ -- .hi-boot files only make sense for the home package.
+
+ searchPathExts (importDirs pkg_conf) mod exts
+
+-- -----------------------------------------------------------------------------
+-- General path searching
+
+searchPathExts
+ :: [FilePath] -- paths to search
+ -> Module -- module name
+ -> [ (
+ FileExt, -- suffix
+ FilePath -> BaseName -> IO FinderCacheEntry -- action
+ )
+ ]
+ -> IO LocalFindResult
+
+searchPathExts paths mod exts
+ = do result <- search to_search
+{-
+ hPutStrLn stderr (showSDoc $
+ vcat [text "Search" <+> ppr mod <+> sep (map (text. fst) exts)
+ , nest 2 (vcat (map text paths))
+ , case result of
+ Succeeded (loc, p) -> text "Found" <+> ppr loc
+ Failed fs -> text "not found"])
+-}
+ return result
+
+ where
+ basename = dots_to_slashes (moduleUserString mod)
+
+ to_search :: [(FilePath, IO FinderCacheEntry)]
+ to_search = [ (file, fn path basename)
+ | path <- paths,
+ (ext,fn) <- exts,
+ let base | path == "." = basename
+ | otherwise = path ++ '/':basename
+ file = base ++ '.':ext
+ ]
+
+ search [] = return (Failed (map fst to_search))
+ search ((file, mk_result) : rest) = do
+ b <- doesFileExist file
+ if b
+ then do { res <- mk_result; return (Succeeded res) }
+ else search rest
+
+mkHomeModLocationSearched :: DynFlags -> Module -> FileExt
+ -> FilePath -> BaseName -> IO FinderCacheEntry
+mkHomeModLocationSearched dflags mod suff path basename = do
+ loc <- mkHomeModLocation2 dflags mod (path ++ '/':basename) suff
+ return (loc, Nothing)
+
+mkHiOnlyModLocation :: DynFlags -> FileExt -> FilePath -> BaseName
+ -> IO FinderCacheEntry
+mkHiOnlyModLocation dflags hisuf path basename = do
+ loc <- hiOnlyModLocation dflags path basename hisuf
+ return (loc, Nothing)
+
+mkPackageModLocation :: DynFlags -> (PackageConfig, Bool) -> FileExt
+ -> FilePath -> BaseName -> IO FinderCacheEntry
+mkPackageModLocation dflags pkg_info hisuf path basename = do
+ loc <- hiOnlyModLocation dflags path basename hisuf
+ return (loc, Just pkg_info)
+
+-- -----------------------------------------------------------------------------
+-- Constructing a home module location
+
+-- This is where we construct the ModLocation for a module in the home
+-- package, for which we have a source file. It is called from three
+-- places:
+--
+-- (a) Here in the finder, when we are searching for a module to import,
+-- using the search path (-i option).
+--
+-- (b) The compilation manager, when constructing the ModLocation for
+-- a "root" module (a source file named explicitly on the command line
+-- or in a :load command in GHCi).
+--
+-- (c) The driver in one-shot mode, when we need to construct a
+-- ModLocation for a source file named on the command-line.
+--
+-- Parameters are:
+--
+-- mod
+-- The name of the module
+--
+-- path
+-- (a): The search path component where the source file was found.
+-- (b) and (c): "."
+--
+-- src_basename
+-- (a): dots_to_slashes (moduleNameUserString mod)
+-- (b) and (c): The filename of the source file, minus its extension
+--
+-- ext
+-- The filename extension of the source file (usually "hs" or "lhs").
+
+mkHomeModLocation :: DynFlags -> Module -> FilePath -> IO ModLocation
+mkHomeModLocation dflags mod src_filename = do
+ let (basename,extension) = splitFilename src_filename
+ mkHomeModLocation2 dflags mod basename extension
+
+mkHomeModLocation2 :: DynFlags
+ -> Module
+ -> FilePath -- Of source module, without suffix
+ -> String -- Suffix
+ -> IO ModLocation
+mkHomeModLocation2 dflags mod src_basename ext = do
+ let mod_basename = dots_to_slashes (moduleUserString mod)
+
+ obj_fn <- mkObjPath dflags src_basename mod_basename
+ hi_fn <- mkHiPath dflags src_basename mod_basename
+
+ return (ModLocation{ ml_hs_file = Just (src_basename ++ '.':ext),
+ ml_hi_file = hi_fn,
+ ml_obj_file = obj_fn })
+
+hiOnlyModLocation :: DynFlags -> FilePath -> String -> Suffix -> IO ModLocation
+hiOnlyModLocation dflags path basename hisuf
+ = do let full_basename = path++'/':basename
+ obj_fn <- mkObjPath dflags full_basename basename
+ return ModLocation{ ml_hs_file = Nothing,
+ ml_hi_file = full_basename ++ '.':hisuf,
+ -- Remove the .hi-boot suffix from
+ -- hi_file, if it had one. We always
+ -- want the name of the real .hi file
+ -- in the ml_hi_file field.
+ ml_obj_file = obj_fn
+ }
+
+-- | Constructs the filename of a .o file for a given source file.
+-- Does /not/ check whether the .o file exists
+mkObjPath
+ :: DynFlags
+ -> FilePath -- the filename of the source file, minus the extension
+ -> String -- the module name with dots replaced by slashes
+ -> IO FilePath
+mkObjPath dflags basename mod_basename
+ = do let
+ odir = outputDir dflags
+ osuf = objectSuf dflags
+
+ obj_basename | Just dir <- odir = dir ++ '/':mod_basename
+ | otherwise = basename
+
+ return (obj_basename ++ '.':osuf)
+
+-- | Constructs the filename of a .hi file for a given source file.
+-- Does /not/ check whether the .hi file exists
+mkHiPath
+ :: DynFlags
+ -> FilePath -- the filename of the source file, minus the extension
+ -> String -- the module name with dots replaced by slashes
+ -> IO FilePath
+mkHiPath dflags basename mod_basename
+ = do let
+ hidir = hiDir dflags
+ hisuf = hiSuf dflags
+
+ hi_basename | Just dir <- hidir = dir ++ '/':mod_basename
+ | otherwise = basename
+
+ return (hi_basename ++ '.':hisuf)
+
+
+-- -----------------------------------------------------------------------------
+-- findLinkable isn't related to the other stuff in here,
+-- but there's no other obvious place for it
+
+findLinkable :: Module -> ModLocation -> IO (Maybe Linkable)
+findLinkable mod locn
+ = do let obj_fn = ml_obj_file locn
+ obj_exist <- doesFileExist obj_fn
+ if not obj_exist
+ then return Nothing
+ else
+ do let stub_fn = case splitFilename3 obj_fn of
+ (dir, base, ext) -> dir ++ "/" ++ base ++ "_stub.o"
+ stub_exist <- doesFileExist stub_fn
+ obj_time <- getModificationTime obj_fn
+ if stub_exist
+ then return (Just (LM obj_time mod [DotO obj_fn, DotO stub_fn]))
+ else return (Just (LM obj_time mod [DotO obj_fn]))
+
+-- -----------------------------------------------------------------------------
+-- Utils
+
+dots_to_slashes = map (\c -> if c == '.' then '/' else c)
+
+
+-- -----------------------------------------------------------------------------
+-- Error messages
+
+cantFindError :: DynFlags -> Module -> FindResult -> SDoc
+cantFindError dflags mod_name find_result
+ = hang (ptext SLIT("Could not find module") <+> quotes (ppr mod_name) <> colon)
+ 2 more_info
+ where
+ more_info
+ = case find_result of
+ PackageHidden pkg
+ -> ptext SLIT("it is a member of package") <+> ppr pkg <> comma
+ <+> ptext SLIT("which is hidden")
+
+ ModuleHidden pkg
+ -> ptext SLIT("it is hidden") <+> parens (ptext SLIT("in package")
+ <+> ppr pkg)
+
+ NotFound files
+ | null files
+ -> ptext SLIT("it is not a module in the current program, or in any known package.")
+ | verbosity dflags < 3
+ -> ptext SLIT("use -v to see a list of the files searched for")
+ | otherwise
+ -> hang (ptext SLIT("locations searched:"))
+ 2 (vcat (map text files))
+
+ Found _ _ -> panic "cantFindErr"
\end{code}