\begin{code}
module Finder (
- initFinder, -- :: [PackageConfig] -> IO (),
- findModule, -- :: ModuleName -> IO (Maybe (Module, ModuleLocation))
- mkHomeModuleLocn, -- :: ModuleName -> String -> Maybe FilePath
- -- -> IO ModuleLocation
- emptyHomeDirCache, -- :: IO ()
- flushPackageCache -- :: [PackageConfig] -> IO ()
+ flushFinderCache, -- :: IO ()
+ FindResult(..),
+ findModule, -- :: ModuleName -> Bool -> IO FindResult
+ findPackageModule, -- :: ModuleName -> Bool -> IO FindResult
+ mkHomeModLocation, -- :: ModuleName -> FilePath -> IO ModLocation
+ findLinkable, -- :: ModuleName -> ModLocation -> IO (Maybe Linkable)
+
+ hiBootExt, -- :: String
+ hiBootVerExt, -- :: String
+
) where
#include "HsVersions.h"
-import HscTypes ( ModuleLocation(..) )
-import CmStaticInfo
-import DriverPhases
+import Module
+import UniqFM ( filterUFM )
+import HscTypes ( Linkable(..), Unlinked(..), IfacePackage(..) )
+import Packages
import DriverState
import DriverUtil
-import Module
-import FiniteMap
import FastString
-import Util
-import Panic ( panic )
import Config
+import Util
+import CmdLineOpts ( DynFlags(..) )
-import IOExts
-import List
-import Directory
-import IO
-import Monad
-import Outputable
-\end{code}
+import DATA_IOREF ( IORef, writeIORef, readIORef )
-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.
+import Data.List
+import System.Directory
+import System.IO
+import Control.Monad
+import Data.Maybe ( isNothing )
-\begin{code}
-initFinder :: [PackageConfig] -> IO ()
-initFinder pkgs = return ()
-
--- empty, and lazilly fill in the package cache
-flushPackageCache :: [PackageConfig] -> IO ()
-flushPackageCache pkgs = return ()
-
-emptyHomeDirCache :: IO ()
-emptyHomeDirCache = return ()
-
-findModule :: ModuleName -> IO (Maybe (Module, ModuleLocation))
-findModule 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_path <- readIORef v_Import_paths
-
- let mod_str = moduleNameUserString mod_name
- basename = map (\c -> if c == '.' then '/' else c) mod_str
- hs = basename ++ ".hs"
- lhs = basename ++ ".lhs"
-
- found <- findOnPath home_path hs
- case found of {
- -- special case to avoid getting "./foo.hs" all the time
- Just "." -> mkHomeModuleLocn mod_name basename (Just hs);
- Just path -> mkHomeModuleLocn mod_name
- (path ++ '/':basename) (Just (path ++ '/':hs));
- Nothing -> do
-
- found <- findOnPath home_path lhs
- case found of {
- -- special case to avoid getting "./foo.hs" all the time
- Just "." -> mkHomeModuleLocn mod_name basename (Just lhs);
- Just path -> mkHomeModuleLocn mod_name
- (path ++ '/':basename) (Just (path ++ '/':lhs));
- Nothing -> do
-
- -- can't find a source file anywhere, check for a lone .hi file.
- hisuf <- readIORef v_Hi_suf
- let hi = basename ++ '.':hisuf
- found <- findOnPath home_path hi
- case found of {
- Just path -> mkHiOnlyModuleLocn mod_name hi;
- Nothing -> do
-
- -- last chance: .hi-boot-<ver> and .hi-boot
- let hi_boot = basename ++ ".hi-boot"
- let hi_boot_ver = basename ++ ".hi-boot-" ++ cHscIfaceFileVersion
- found <- findOnPath home_path hi_boot_ver
- case found of {
- Just path -> mkHiOnlyModuleLocn mod_name hi;
- Nothing -> do
- found <- findOnPath home_path hi_boot
- case found of {
- Just path -> mkHiOnlyModuleLocn mod_name hi;
- Nothing -> return Nothing
- }}}}}
-
-
-mkHiOnlyModuleLocn mod_name hi_file = do
- return (Just (mkHomeModule mod_name,
- ModuleLocation{
- ml_hspp_file = Nothing,
- ml_hs_file = Nothing,
- ml_hi_file = hi_file,
- ml_obj_file = Nothing
- }
- ))
-
--- The .hi file always follows the module name, whereas the object
--- file may follow the name of the source file in the case where the
--- two differ (see summariseFile in compMan/CompManager.lhs).
-
-mkHomeModuleLocn mod_name basename maybe_source_fn = do
-
- hisuf <- readIORef v_Hi_suf
- hidir <- readIORef v_Hi_dir
-
- let hi_rest = basename ++ '.':hisuf
- hi_file | Just d <- hidir = d ++ '/':hi_rest
- | otherwise = hi_rest
-
- -- 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) >>= osuf_ify
-
- return (Just (mkHomeModule mod_name,
- ModuleLocation{
- ml_hspp_file = Nothing,
- ml_hs_file = maybe_source_fn,
- ml_hi_file = hi_file,
- ml_obj_file = Just o_file
- }
- ))
-
-
-maybePackageModule :: ModuleName -> IO (Maybe (Module, ModuleLocation))
-maybePackageModule mod_name = do
- pkgs <- getPackageInfo
-
- -- hi-suffix for packages depends on the build tag.
+-- -----------------------------------------------------------------------------
+-- 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
+
+GLOBAL_VAR(finder_cache, emptyModuleEnv, ModuleEnv FinderCacheEntry)
+
+type FinderCacheEntry = (ModLocation,Maybe (PackageConfig,Bool))
+
+-- remove all the home modules from the cache; package modules are
+-- assumed to not move around during a session.
+flushFinderCache :: IO ()
+flushFinderCache = do
+ fm <- readIORef finder_cache
+ writeIORef finder_cache (filterUFM (\(loc,m) -> isNothing m) fm)
+
+addToFinderCache :: Module -> FinderCacheEntry -> IO ()
+addToFinderCache mod_name entry = do
+ fm <- readIORef finder_cache
+ writeIORef finder_cache (extendModuleEnv fm mod_name entry)
+
+lookupFinderCache :: Module -> IO (Maybe FinderCacheEntry)
+lookupFinderCache 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 IfacePackage
+ -- 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.
+
+findModule :: DynFlags -> Module -> Bool -> IO FindResult
+findModule = cached findModule'
+
+findModule' :: DynFlags -> Module -> Bool -> IO FindResult
+findModule' dflags name explicit = do
+ r <- findPackageModule' dflags name explicit
+ case r of
+ NotFound pkg_files -> do
+ j <- maybeHomeModule dflags name
+ case j of
+ NotFound home_files ->
+ return (NotFound (home_files ++ pkg_files))
+ other_result
+ -> return other_result
+ other_result
+ -> return other_result
+
+cached fn dflags name explicit = do
+ m <- lookupFinderCache name
+ case m of
+ Nothing -> fn dflags name explicit
+ Just (loc,maybe_pkg)
+ | Just err <- visible explicit maybe_pkg -> return err
+ | otherwise -> return (Found loc (pkgInfoToId maybe_pkg))
+
+pkgInfoToId :: Maybe (PackageConfig,Bool) -> IfacePackage
+pkgInfoToId (Just (pkg,_)) = ExternalPackage (mkPackageId (package pkg))
+pkgInfoToId Nothing = ThisPackage
+
+-- Is a module visible or not? Returns Nothing if the import is ok,
+-- or Just err if there's a visibility error.
+visible :: Bool -> Maybe (PackageConfig,Bool) -> Maybe FindResult
+visible explicit maybe_pkg
+ | Nothing <- maybe_pkg = Nothing -- home module ==> YES
+ | not explicit = Nothing -- implicit import ==> YES
+ | Just (pkg, exposed_module) <- maybe_pkg
+ = case () of
+ _ | not exposed_module -> Just (ModuleHidden pkgname)
+ | not (exposed pkg) -> Just (PackageHidden pkgname)
+ | otherwise -> Nothing
+ where
+ pkgname = packageConfigId pkg
+
+
+hiBootExt = "hi-boot"
+hiBootVerExt = "hi-boot-" ++ cHscIfaceFileVersion
+
+maybeHomeModule :: DynFlags -> Module -> IO FindResult
+maybeHomeModule dflags mod = do
+ let home_path = importPaths dflags
+ hisuf <- readIORef v_Hi_suf
+ mode <- readIORef v_GhcMode
+
+ let
+ source_exts =
+ [ ("hs", mkHomeModLocationSearched mod)
+ , ("lhs", mkHomeModLocationSearched mod)
+ ]
+
+ hi_exts = [ (hisuf, mkHiOnlyModLocation hisuf mod) ]
+
+ boot_exts =
+ [ (hiBootVerExt, mkHiOnlyModLocation hisuf mod)
+ , (hiBootExt, mkHiOnlyModLocation hisuf mod)
+ ]
+
+ -- 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.
+ --
+ -- When generating dependencies, we're interested in either category.
+ --
+ exts
+ | mode == DoMkDependHS = hi_exts ++ source_exts ++ boot_exts
+ | isCompManagerMode mode = source_exts
+ | otherwise {-one-shot-} = hi_exts ++ boot_exts
+
+ searchPathExts home_path mod exts
+
+-- -----------------------------------------------------------------------------
+-- Looking for a package module
+
+findPackageModule :: DynFlags -> Module -> Bool -> IO FindResult
+findPackageModule = cached findPackageModule'
+
+findPackageModule' :: DynFlags -> Module -> Bool -> IO FindResult
+findPackageModule' dflags mod explicit = do
+ mode <- readIORef v_GhcMode
+
+ case moduleToPackageConfig dflags mod of
+ Nothing -> return (NotFound [])
+ pkg_info@(Just (pkg_conf, module_exposed))
+ | Just err <- visible explicit pkg_info -> return err
+ | otherwise -> findPackageIface mode mod paths pkg_info
+ where
+ paths = importDirs pkg_conf
+
+findPackageIface
+ :: GhcMode
+ -> Module
+ -> [FilePath]
+ -> Maybe (PackageConfig,Bool)
+ -> IO FindResult
+findPackageIface mode mod imp_dirs pkg_info = do
+ -- hi-suffix for packages depends on the build tag.
package_hisuf <-
do tag <- readIORef v_Build_tag
if null tag
then return "hi"
else return (tag ++ "_hi")
- let basename = moduleNameUserString mod_name
- hi = basename ++ '.':package_hisuf
-
- found <- findOnPackagePath pkgs hi
- case found of
- Nothing -> return Nothing
- Just (pkg_name,path) ->
- return (Just (mkModule mod_name pkg_name,
- ModuleLocation{
- ml_hspp_file = Nothing,
- ml_hs_file = Nothing,
- ml_hi_file = path,
- ml_obj_file = Nothing
- }
- ))
-
-findOnPackagePath :: [PackageConfig] -> String
- -> IO (Maybe (PackageName,FilePath))
-findOnPackagePath pkgs file = loop pkgs
- where
- loop [] = return Nothing
- loop (p:ps) = do
- found <- findOnPath (import_dirs p) file
- case found of
- Nothing -> loop ps
- Just f -> return (Just (mkFastString (name p), f))
-
-findOnPath :: [String] -> String -> IO (Maybe FilePath)
-findOnPath path s = loop path
- where
- loop [] = return Nothing
- loop (d:ds) = do
- let file = d ++ '/':s
- b <- doesFileExist file
- if b then return (Just d) else loop ds
+ let
+ hi_exts =
+ [ (package_hisuf,
+ mkPackageModLocation pkg_info package_hisuf mod) ]
+
+ source_exts =
+ [ ("hs", mkPackageModLocation pkg_info package_hisuf mod)
+ , ("lhs", mkPackageModLocation pkg_info package_hisuf mod)
+ ]
+
+ -- mkdependHS needs to look for source files in packages too, so
+ -- that we can make dependencies between package before they have
+ -- been built.
+ exts
+ | mode == DoMkDependHS = 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 imp_dirs mod exts
+
+-- -----------------------------------------------------------------------------
+-- General path searching
+
+searchPathExts
+ :: [FilePath] -- paths to search
+ -> Module -- module name
+ -> [ (
+ String, -- suffix
+ String -> String -> String -> IO FindResult -- action
+ )
+ ]
+ -> IO FindResult
+
+searchPathExts path mod exts = search to_search
+ where
+ basename = dots_to_slashes (moduleUserString mod)
+
+ to_search :: [(FilePath, IO FindResult)]
+ to_search = [ (file, fn p basename ext)
+ | p <- path,
+ (ext,fn) <- exts,
+ let base | p == "." = basename
+ | otherwise = p ++ '/':basename
+ file = base ++ '.':ext
+ ]
+
+ search [] = return (NotFound (map fst to_search))
+ search ((file, result) : rest) = do
+ b <- doesFileExist file
+ if b
+ then result
+ else search rest
+
+-- -----------------------------------------------------------------------------
+-- Building ModLocations
+
+mkHiOnlyModLocation hisuf mod path basename _ext = do
+ -- basename == dots_to_slashes (moduleNameUserString mod)
+ loc <- hiOnlyModLocation path basename hisuf
+ addToFinderCache mod (loc, Nothing)
+ return (Found loc ThisPackage)
+
+mkPackageModLocation pkg_info hisuf mod path basename _ext = do
+ -- basename == dots_to_slashes (moduleNameUserString mod)
+ loc <- hiOnlyModLocation path basename hisuf
+ addToFinderCache mod (loc, pkg_info)
+ return (Found loc (pkgInfoToId pkg_info))
+
+hiOnlyModLocation path basename hisuf
+ = do let full_basename = path++'/':basename
+ obj_fn <- mkObjPath full_basename basename
+ return ModLocation{ ml_hspp_file = Nothing,
+ 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
+ }
+
+-- -----------------------------------------------------------------------------
+-- 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 mod src_filename = do
+ let (basename,extension) = splitFilename src_filename
+ mkHomeModLocation' mod basename extension
+
+mkHomeModLocationSearched mod path basename ext = do
+ loc <- mkHomeModLocation' mod (path ++ '/':basename) ext
+ return (Found loc ThisPackage)
+
+mkHomeModLocation' mod src_basename ext = do
+ let mod_basename = dots_to_slashes (moduleUserString mod)
+
+ obj_fn <- mkObjPath src_basename mod_basename
+ hi_fn <- mkHiPath src_basename mod_basename
+
+ let loc = ModLocation{ ml_hspp_file = Nothing,
+ ml_hs_file = Just (src_basename ++ '.':ext),
+ ml_hi_file = hi_fn,
+ ml_obj_file = obj_fn }
+
+ addToFinderCache mod (loc, Nothing)
+ return loc
+
+-- | Constructs the filename of a .o file for a given source file.
+-- Does /not/ check whether the .o file exists
+mkObjPath
+ :: FilePath -- the filename of the source file, minus the extension
+ -> String -- the module name with dots replaced by slashes
+ -> IO FilePath
+mkObjPath basename mod_basename
+ = do odir <- readIORef v_Output_dir
+ osuf <- readIORef v_Object_suf
+
+ let 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
+ :: FilePath -- the filename of the source file, minus the extension
+ -> String -- the module name with dots replaced by slashes
+ -> IO FilePath
+mkHiPath basename mod_basename
+ = do hidir <- readIORef v_Hi_dir
+ hisuf <- readIORef v_Hi_suf
+
+ let 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)
+
\end{code}