/ghc-7.0.4/compiler/ghci/Linker.lhs
Haskell | 1209 lines | 749 code | 175 blank | 285 comment | 42 complexity | d519c283b0401c502b9b1d791453c23f MD5 | raw file
Possible License(s): BSD-3-Clause, BSD-2-Clause
- %
- % (c) The University of Glasgow 2005-2006
- %
- \begin{code}
- -- | The dynamic linker for GHCi.
- --
- -- This module deals with the top-level issues of dynamic linking,
- -- calling the object-code linker and the byte-code linker where
- -- necessary.
- {-# OPTIONS -fno-cse #-}
- -- -fno-cse is needed for GLOBAL_VAR's to behave properly
- module Linker ( HValue, getHValue, showLinkerState,
- linkExpr, unload, withExtendedLinkEnv,
- extendLinkEnv, deleteFromLinkEnv,
- extendLoadedPkgs,
- linkPackages,initDynLinker,
- dataConInfoPtrToName
- ) where
- #include "HsVersions.h"
- import LoadIface
- import ObjLink
- import ByteCodeLink
- import ByteCodeItbls
- import ByteCodeAsm
- import CgInfoTbls
- import SMRep
- import IfaceEnv
- import TcRnMonad
- import Packages
- import DriverPhases
- import Finder
- import HscTypes
- import Name
- import NameEnv
- import NameSet
- import qualified OccName
- import UniqFM
- import Module
- import ListSetOps
- import DynFlags
- import BasicTypes
- import Outputable
- import Panic
- import Util
- import StaticFlags
- import ErrUtils
- import SrcLoc
- import qualified Maybes
- import UniqSet
- import Constants
- import FastString
- import Config
- -- Standard libraries
- import Control.Monad
- import Data.Char
- import Data.IORef
- import Data.List
- import qualified Data.Map as Map
- import Foreign
- import Control.Concurrent.MVar
- import System.FilePath
- import System.IO
- import System.Directory
- import Distribution.Package hiding (depends, PackageId)
- import Exception
- \end{code}
- %************************************************************************
- %* *
- The Linker's state
- %* *
- %************************************************************************
- The persistent linker state *must* match the actual state of the
- C dynamic linker at all times, so we keep it in a private global variable.
- The PersistentLinkerState maps Names to actual closures (for
- interpreted code only), for use during linking.
- \begin{code}
- GLOBAL_MVAR(v_PersistentLinkerState, panic "Dynamic linker not initialised", PersistentLinkerState)
- GLOBAL_VAR(v_InitLinkerDone, False, Bool) -- Set True when dynamic linker is initialised
- data PersistentLinkerState
- = PersistentLinkerState {
- -- Current global mapping from Names to their true values
- closure_env :: ClosureEnv,
- -- The current global mapping from RdrNames of DataCons to
- -- info table addresses.
- -- When a new Unlinked is linked into the running image, or an existing
- -- module in the image is replaced, the itbl_env must be updated
- -- appropriately.
- itbl_env :: !ItblEnv,
- -- The currently loaded interpreted modules (home package)
- bcos_loaded :: ![Linkable],
- -- And the currently-loaded compiled modules (home package)
- objs_loaded :: ![Linkable],
- -- The currently-loaded packages; always object code
- -- Held, as usual, in dependency order; though I am not sure if
- -- that is really important
- pkgs_loaded :: ![PackageId]
- }
- emptyPLS :: DynFlags -> PersistentLinkerState
- emptyPLS _ = PersistentLinkerState {
- closure_env = emptyNameEnv,
- itbl_env = emptyNameEnv,
- pkgs_loaded = init_pkgs,
- bcos_loaded = [],
- objs_loaded = [] }
-
- -- Packages that don't need loading, because the compiler
- -- shares them with the interpreted program.
- --
- -- The linker's symbol table is populated with RTS symbols using an
- -- explicit list. See rts/Linker.c for details.
- where init_pkgs = [rtsPackageId]
- \end{code}
- \begin{code}
- extendLoadedPkgs :: [PackageId] -> IO ()
- extendLoadedPkgs pkgs =
- modifyMVar_ v_PersistentLinkerState $ \s ->
- return s{ pkgs_loaded = pkgs ++ pkgs_loaded s }
- extendLinkEnv :: [(Name,HValue)] -> IO ()
- -- Automatically discards shadowed bindings
- extendLinkEnv new_bindings =
- modifyMVar_ v_PersistentLinkerState $ \pls ->
- let new_closure_env = extendClosureEnv (closure_env pls) new_bindings
- in return pls{ closure_env = new_closure_env }
- deleteFromLinkEnv :: [Name] -> IO ()
- deleteFromLinkEnv to_remove =
- modifyMVar_ v_PersistentLinkerState $ \pls ->
- let new_closure_env = delListFromNameEnv (closure_env pls) to_remove
- in return pls{ closure_env = new_closure_env }
- -- | Given a data constructor in the heap, find its Name.
- -- The info tables for data constructors have a field which records
- -- the source name of the constructor as a Ptr Word8 (UTF-8 encoded
- -- string). The format is:
- --
- -- > Package:Module.Name
- --
- -- We use this string to lookup the interpreter's internal representation of the name
- -- using the lookupOrig.
- --
- dataConInfoPtrToName :: Ptr () -> TcM (Either String Name)
- dataConInfoPtrToName x = do
- theString <- liftIO $ do
- let ptr = castPtr x :: Ptr StgInfoTable
- conDescAddress <- getConDescAddress ptr
- peekArray0 0 conDescAddress
- let (pkg, mod, occ) = parse theString
- pkgFS = mkFastStringByteList pkg
- modFS = mkFastStringByteList mod
- occFS = mkFastStringByteList occ
- occName = mkOccNameFS OccName.dataName occFS
- modName = mkModule (fsToPackageId pkgFS) (mkModuleNameFS modFS)
- return (Left$ showSDoc$ ppr modName <> dot <> ppr occName )
- `recoverM` (Right `fmap` lookupOrig modName occName)
- where
- {- To find the string in the constructor's info table we need to consider
- the layout of info tables relative to the entry code for a closure.
- An info table can be next to the entry code for the closure, or it can
- be separate. The former (faster) is used in registerised versions of ghc,
- and the latter (portable) is for non-registerised versions.
- The diagrams below show where the string is to be found relative to
- the normal info table of the closure.
- 1) Code next to table:
- --------------
- | | <- pointer to the start of the string
- --------------
- | | <- the (start of the) info table structure
- | |
- | |
- --------------
- | entry code |
- | .... |
- In this case the pointer to the start of the string can be found in
- the memory location _one word before_ the first entry in the normal info
- table.
- 2) Code NOT next to table:
- --------------
- info table structure -> | *------------------> --------------
- | | | entry code |
- | | | .... |
- --------------
- ptr to start of str -> | |
- --------------
- In this case the pointer to the start of the string can be found
- in the memory location: info_table_ptr + info_table_size
- -}
- getConDescAddress :: Ptr StgInfoTable -> IO (Ptr Word8)
- getConDescAddress ptr
- | ghciTablesNextToCode = do
- offsetToString <- peek $ ptr `plusPtr` (- wORD_SIZE)
- return $ (ptr `plusPtr` stdInfoTableSizeB) `plusPtr` (fromIntegral (offsetToString :: StgWord))
- | otherwise =
- peek $ intPtrToPtr $ (ptrToIntPtr ptr) + fromIntegral stdInfoTableSizeB
- -- parsing names is a little bit fiddly because we have a string in the form:
- -- pkg:A.B.C.foo, and we want to split it into three parts: ("pkg", "A.B.C", "foo").
- -- Thus we split at the leftmost colon and the rightmost occurrence of the dot.
- -- It would be easier if the string was in the form pkg:A.B.C:foo, but alas
- -- this is not the conventional way of writing Haskell names. We stick with
- -- convention, even though it makes the parsing code more troublesome.
- -- Warning: this code assumes that the string is well formed.
- parse :: [Word8] -> ([Word8], [Word8], [Word8])
- parse input
- = ASSERT (all (>0) (map length [pkg, mod, occ])) (pkg, mod, occ)
- where
- dot = fromIntegral (ord '.')
- (pkg, rest1) = break (== fromIntegral (ord ':')) input
- (mod, occ)
- = (concat $ intersperse [dot] $ reverse modWords, occWord)
- where
- (modWords, occWord) = ASSERT (length rest1 > 0) (parseModOcc [] (tail rest1))
- parseModOcc :: [[Word8]] -> [Word8] -> ([[Word8]], [Word8])
- parseModOcc acc str
- = case break (== dot) str of
- (top, []) -> (acc, top)
- (top, _:bot) -> parseModOcc (top : acc) bot
-
- -- | Get the 'HValue' associated with the given name.
- --
- -- May cause loading the module that contains the name.
- --
- -- Throws a 'ProgramError' if loading fails or the name cannot be found.
- getHValue :: HscEnv -> Name -> IO HValue
- getHValue hsc_env name = do
- pls <- modifyMVar v_PersistentLinkerState $ \pls -> do
- if (isExternalName name) then do
- (pls', ok) <- linkDependencies hsc_env pls noSrcSpan [nameModule name]
- if (failed ok) then ghcError (ProgramError "")
- else return (pls', pls')
- else
- return (pls, pls)
- lookupName (closure_env pls) name
-
- linkDependencies :: HscEnv -> PersistentLinkerState
- -> SrcSpan -> [Module]
- -> IO (PersistentLinkerState, SuccessFlag)
- linkDependencies hsc_env pls span needed_mods = do
- let hpt = hsc_HPT hsc_env
- dflags = hsc_dflags hsc_env
- -- The interpreter and dynamic linker can only handle object code built
- -- the "normal" way, i.e. no non-std ways like profiling or ticky-ticky.
- -- So here we check the build tag: if we're building a non-standard way
- -- then we need to find & link object files built the "normal" way.
- maybe_normal_osuf <- checkNonStdWay dflags span
- -- Find what packages and linkables are required
- (lnks, pkgs) <- getLinkDeps hsc_env hpt pls
- maybe_normal_osuf span needed_mods
- -- Link the packages and modules required
- pls1 <- linkPackages' dflags pkgs pls
- linkModules dflags pls1 lnks
- -- | Temporarily extend the linker state.
- withExtendedLinkEnv :: (MonadIO m, ExceptionMonad m) =>
- [(Name,HValue)] -> m a -> m a
- withExtendedLinkEnv new_env action
- = gbracket (liftIO $ extendLinkEnv new_env)
- (\_ -> reset_old_env)
- (\_ -> action)
- where
- -- Remember that the linker state might be side-effected
- -- during the execution of the IO action, and we don't want to
- -- lose those changes (we might have linked a new module or
- -- package), so the reset action only removes the names we
- -- added earlier.
- reset_old_env = liftIO $ do
- modifyMVar_ v_PersistentLinkerState $ \pls ->
- let cur = closure_env pls
- new = delListFromNameEnv cur (map fst new_env)
- in return pls{ closure_env = new }
- -- filterNameMap removes from the environment all entries except
- -- those for a given set of modules;
- -- Note that this removes all *local* (i.e. non-isExternal) names too
- -- (these are the temporary bindings from the command line).
- -- Used to filter both the ClosureEnv and ItblEnv
- filterNameMap :: [Module] -> NameEnv (Name, a) -> NameEnv (Name, a)
- filterNameMap mods env
- = filterNameEnv keep_elt env
- where
- keep_elt (n,_) = isExternalName n
- && (nameModule n `elem` mods)
- \end{code}
- \begin{code}
- -- | Display the persistent linker state.
- showLinkerState :: IO ()
- showLinkerState
- = do pls <- readMVar v_PersistentLinkerState
- printDump (vcat [text "----- Linker state -----",
- text "Pkgs:" <+> ppr (pkgs_loaded pls),
- text "Objs:" <+> ppr (objs_loaded pls),
- text "BCOs:" <+> ppr (bcos_loaded pls)])
- \end{code}
-
-
- %************************************************************************
- %* *
- \subsection{Initialisation}
- %* *
- %************************************************************************
- \begin{code}
- -- | Initialise the dynamic linker. This entails
- --
- -- a) Calling the C initialisation procedure,
- --
- -- b) Loading any packages specified on the command line,
- --
- -- c) Loading any packages specified on the command line, now held in the
- -- @-l@ options in @v_Opt_l@,
- --
- -- d) Loading any @.o\/.dll@ files specified on the command line, now held
- -- in @v_Ld_inputs@,
- --
- -- e) Loading any MacOS frameworks.
- --
- -- NOTE: This function is idempotent; if called more than once, it does
- -- nothing. This is useful in Template Haskell, where we call it before
- -- trying to link.
- --
- initDynLinker :: DynFlags -> IO ()
- initDynLinker dflags =
- modifyMVar_ v_PersistentLinkerState $ \pls0 -> do
- done <- readIORef v_InitLinkerDone
- if done then return pls0
- else do writeIORef v_InitLinkerDone True
- reallyInitDynLinker dflags
- reallyInitDynLinker :: DynFlags -> IO PersistentLinkerState
- reallyInitDynLinker dflags =
- do { -- Initialise the linker state
- let pls0 = emptyPLS dflags
- -- (a) initialise the C dynamic linker
- ; initObjLinker
- -- (b) Load packages from the command-line
- ; pls <- linkPackages' dflags (preloadPackages (pkgState dflags)) pls0
- -- (c) Link libraries from the command-line
- ; let optl = getOpts dflags opt_l
- ; let minus_ls = [ lib | '-':'l':lib <- optl ]
- -- (d) Link .o files from the command-line
- ; let lib_paths = libraryPaths dflags
- ; cmdline_ld_inputs <- readIORef v_Ld_inputs
- ; classified_ld_inputs <- mapM classifyLdInput cmdline_ld_inputs
- -- (e) Link any MacOS frameworks
- ; let framework_paths
- | isDarwinTarget = frameworkPaths dflags
- | otherwise = []
- ; let frameworks
- | isDarwinTarget = cmdlineFrameworks dflags
- | otherwise = []
- -- Finally do (c),(d),(e)
- ; let cmdline_lib_specs = [ l | Just l <- classified_ld_inputs ]
- ++ map DLL minus_ls
- ++ map Framework frameworks
- ; if null cmdline_lib_specs then return pls
- else do
- { mapM_ (preloadLib dflags lib_paths framework_paths) cmdline_lib_specs
- ; maybePutStr dflags "final link ... "
- ; ok <- resolveObjs
- ; if succeeded ok then maybePutStrLn dflags "done"
- else ghcError (ProgramError "linking extra libraries/objects failed")
- ; return pls
- }}
- classifyLdInput :: FilePath -> IO (Maybe LibrarySpec)
- classifyLdInput f
- | isObjectFilename f = return (Just (Object f))
- | isDynLibFilename f = return (Just (DLLPath f))
- | otherwise = do
- hPutStrLn stderr ("Warning: ignoring unrecognised input `" ++ f ++ "'")
- return Nothing
- preloadLib :: DynFlags -> [String] -> [String] -> LibrarySpec -> IO ()
- preloadLib dflags lib_paths framework_paths lib_spec
- = do maybePutStr dflags ("Loading object " ++ showLS lib_spec ++ " ... ")
- case lib_spec of
- Object static_ish
- -> do b <- preload_static lib_paths static_ish
- maybePutStrLn dflags (if b then "done"
- else "not found")
- Archive static_ish
- -> do b <- preload_static_archive lib_paths static_ish
- maybePutStrLn dflags (if b then "done"
- else "not found")
- DLL dll_unadorned
- -> do maybe_errstr <- loadDynamic lib_paths dll_unadorned
- case maybe_errstr of
- Nothing -> maybePutStrLn dflags "done"
- Just mm -> preloadFailed mm lib_paths lib_spec
- DLLPath dll_path
- -> do maybe_errstr <- loadDLL dll_path
- case maybe_errstr of
- Nothing -> maybePutStrLn dflags "done"
- Just mm -> preloadFailed mm lib_paths lib_spec
- Framework framework
- | isDarwinTarget
- -> do maybe_errstr <- loadFramework framework_paths framework
- case maybe_errstr of
- Nothing -> maybePutStrLn dflags "done"
- Just mm -> preloadFailed mm framework_paths lib_spec
- | otherwise -> panic "preloadLib Framework"
- where
- preloadFailed :: String -> [String] -> LibrarySpec -> IO ()
- preloadFailed sys_errmsg paths spec
- = do maybePutStr dflags "failed.\n"
- ghcError $
- CmdLineError (
- "user specified .o/.so/.DLL could not be loaded ("
- ++ sys_errmsg ++ ")\nWhilst trying to load: "
- ++ showLS spec ++ "\nAdditional directories searched:"
- ++ (if null paths then " (none)" else
- (concat (intersperse "\n" (map (" "++) paths)))))
-
- -- Not interested in the paths in the static case.
- preload_static _paths name
- = do b <- doesFileExist name
- if not b then return False
- else loadObj name >> return True
- preload_static_archive _paths name
- = do b <- doesFileExist name
- if not b then return False
- else loadArchive name >> return True
- \end{code}
- %************************************************************************
- %* *
- Link a byte-code expression
- %* *
- %************************************************************************
- \begin{code}
- -- | Link a single expression, /including/ first linking packages and
- -- modules that this expression depends on.
- --
- -- Raises an IO exception ('ProgramError') if it can't find a compiled
- -- version of the dependents to link.
- --
- linkExpr :: HscEnv -> SrcSpan -> UnlinkedBCO -> IO HValue
- linkExpr hsc_env span root_ul_bco
- = do {
- -- Initialise the linker (if it's not been done already)
- let dflags = hsc_dflags hsc_env
- ; initDynLinker dflags
- -- Take lock for the actual work.
- ; modifyMVar v_PersistentLinkerState $ \pls0 -> do {
- -- Link the packages and modules required
- ; (pls, ok) <- linkDependencies hsc_env pls0 span needed_mods
- ; if failed ok then
- ghcError (ProgramError "")
- else do {
- -- Link the expression itself
- let ie = itbl_env pls
- ce = closure_env pls
- -- Link the necessary packages and linkables
- ; (_, (root_hval:_)) <- linkSomeBCOs False ie ce [root_ul_bco]
- ; return (pls, root_hval)
- }}}
- where
- free_names = nameSetToList (bcoFreeNames root_ul_bco)
- needed_mods :: [Module]
- needed_mods = [ nameModule n | n <- free_names,
- isExternalName n, -- Names from other modules
- not (isWiredInName n) -- Exclude wired-in names
- ] -- (see note below)
- -- Exclude wired-in names because we may not have read
- -- their interface files, so getLinkDeps will fail
- -- All wired-in names are in the base package, which we link
- -- by default, so we can safely ignore them here.
-
- dieWith :: SrcSpan -> Message -> IO a
- dieWith span msg = ghcError (ProgramError (showSDoc (mkLocMessage span msg)))
- checkNonStdWay :: DynFlags -> SrcSpan -> IO (Maybe String)
- checkNonStdWay dflags srcspan = do
- let tag = buildTag dflags
- if null tag {- || tag == "dyn" -} then return Nothing else do
- -- see #3604: object files compiled for way "dyn" need to link to the
- -- dynamic packages, so we can't load them into a statically-linked GHCi.
- -- we have to treat "dyn" in the same way as "prof".
- --
- -- In the future when GHCi is dynamically linked we should be able to relax
- -- this, but they we may have to make it possible to load either ordinary
- -- .o files or -dynamic .o files into GHCi (currently that's not possible
- -- because the dynamic objects contain refs to e.g. __stginit_base_Prelude_dyn
- -- whereas we have __stginit_base_Prelude_.
- let default_osuf = phaseInputExt StopLn
- if objectSuf dflags == default_osuf
- then failNonStd srcspan
- else return (Just default_osuf)
- failNonStd :: SrcSpan -> IO (Maybe String)
- failNonStd srcspan = dieWith srcspan $
- ptext (sLit "Dynamic linking required, but this is a non-standard build (eg. prof).") $$
- ptext (sLit "You need to build the program twice: once the normal way, and then") $$
- ptext (sLit "in the desired way using -osuf to set the object file suffix.")
-
- getLinkDeps :: HscEnv -> HomePackageTable
- -> PersistentLinkerState
- -> Maybe String -- the "normal" object suffix
- -> SrcSpan -- for error messages
- -> [Module] -- If you need these
- -> IO ([Linkable], [PackageId]) -- ... then link these first
- -- Fails with an IO exception if it can't find enough files
- getLinkDeps hsc_env hpt pls maybe_normal_osuf span mods
- -- Find all the packages and linkables that a set of modules depends on
- = do {
- -- 1. Find the dependent home-pkg-modules/packages from each iface
- (mods_s, pkgs_s) <- follow_deps mods emptyUniqSet emptyUniqSet;
- let {
- -- 2. Exclude ones already linked
- -- Main reason: avoid findModule calls in get_linkable
- mods_needed = mods_s `minusList` linked_mods ;
- pkgs_needed = pkgs_s `minusList` pkgs_loaded pls ;
- linked_mods = map (moduleName.linkableModule)
- (objs_loaded pls ++ bcos_loaded pls)
- } ;
-
- -- putStrLn (showSDoc (ppr mods_s)) ;
- -- 3. For each dependent module, find its linkable
- -- This will either be in the HPT or (in the case of one-shot
- -- compilation) we may need to use maybe_getFileLinkable
- lnks_needed <- mapM (get_linkable maybe_normal_osuf) mods_needed ;
- return (lnks_needed, pkgs_needed) }
- where
- dflags = hsc_dflags hsc_env
- this_pkg = thisPackage dflags
- -- The ModIface contains the transitive closure of the module dependencies
- -- within the current package, *except* for boot modules: if we encounter
- -- a boot module, we have to find its real interface and discover the
- -- dependencies of that. Hence we need to traverse the dependency
- -- tree recursively. See bug #936, testcase ghci/prog007.
- follow_deps :: [Module] -- modules to follow
- -> UniqSet ModuleName -- accum. module dependencies
- -> UniqSet PackageId -- accum. package dependencies
- -> IO ([ModuleName], [PackageId]) -- result
- follow_deps [] acc_mods acc_pkgs
- = return (uniqSetToList acc_mods, uniqSetToList acc_pkgs)
- follow_deps (mod:mods) acc_mods acc_pkgs
- = do
- mb_iface <- initIfaceCheck hsc_env $
- loadInterface msg mod (ImportByUser False)
- iface <- case mb_iface of
- Maybes.Failed err -> ghcError (ProgramError (showSDoc err))
- Maybes.Succeeded iface -> return iface
- when (mi_boot iface) $ link_boot_mod_error mod
- let
- pkg = modulePackageId mod
- deps = mi_deps iface
- pkg_deps = dep_pkgs deps
- (boot_deps, mod_deps) = partitionWith is_boot (dep_mods deps)
- where is_boot (m,True) = Left m
- is_boot (m,False) = Right m
- boot_deps' = filter (not . (`elementOfUniqSet` acc_mods)) boot_deps
- acc_mods' = addListToUniqSet acc_mods (moduleName mod : mod_deps)
- acc_pkgs' = addListToUniqSet acc_pkgs pkg_deps
- --
- if pkg /= this_pkg
- then follow_deps mods acc_mods (addOneToUniqSet acc_pkgs' pkg)
- else follow_deps (map (mkModule this_pkg) boot_deps' ++ mods)
- acc_mods' acc_pkgs'
- where
- msg = text "need to link module" <+> ppr mod <+>
- text "due to use of Template Haskell"
- link_boot_mod_error mod =
- ghcError (ProgramError (showSDoc (
- text "module" <+> ppr mod <+>
- text "cannot be linked; it is only available as a boot module")))
- no_obj :: Outputable a => a -> IO b
- no_obj mod = dieWith span $
- ptext (sLit "cannot find object file for module ") <>
- quotes (ppr mod) $$
- while_linking_expr
-
- while_linking_expr = ptext (sLit "while linking an interpreted expression")
- -- This one is a build-system bug
- get_linkable maybe_normal_osuf mod_name -- A home-package module
- | Just mod_info <- lookupUFM hpt mod_name
- = adjust_linkable (Maybes.expectJust "getLinkDeps" (hm_linkable mod_info))
- | otherwise
- = do -- It's not in the HPT because we are in one shot mode,
- -- so use the Finder to get a ModLocation...
- mb_stuff <- findHomeModule hsc_env mod_name
- case mb_stuff of
- Found loc mod -> found loc mod
- _ -> no_obj mod_name
- where
- found loc mod = do {
- -- ...and then find the linkable for it
- mb_lnk <- findObjectLinkableMaybe mod loc ;
- case mb_lnk of {
- Nothing -> no_obj mod ;
- Just lnk -> adjust_linkable lnk
- }}
- adjust_linkable lnk
- | Just osuf <- maybe_normal_osuf = do
- new_uls <- mapM (adjust_ul osuf) (linkableUnlinked lnk)
- return lnk{ linkableUnlinked=new_uls }
- | otherwise =
- return lnk
- adjust_ul osuf (DotO file) = do
- let new_file = replaceExtension file osuf
- ok <- doesFileExist new_file
- if (not ok)
- then dieWith span $
- ptext (sLit "cannot find normal object file ")
- <> quotes (text new_file) $$ while_linking_expr
- else return (DotO new_file)
- adjust_ul _ _ = panic "adjust_ul"
- \end{code}
- %************************************************************************
- %* *
- Link some linkables
- The linkables may consist of a mixture of
- byte-code modules and object modules
- %* *
- %************************************************************************
- \begin{code}
- linkModules :: DynFlags -> PersistentLinkerState -> [Linkable]
- -> IO (PersistentLinkerState, SuccessFlag)
- linkModules dflags pls linkables
- = mask_ $ do -- don't want to be interrupted by ^C in here
-
- let (objs, bcos) = partition isObjectLinkable
- (concatMap partitionLinkable linkables)
- -- Load objects first; they can't depend on BCOs
- (pls1, ok_flag) <- dynLinkObjs dflags pls objs
- if failed ok_flag then
- return (pls1, Failed)
- else do
- pls2 <- dynLinkBCOs pls1 bcos
- return (pls2, Succeeded)
-
- -- HACK to support f-x-dynamic in the interpreter; no other purpose
- partitionLinkable :: Linkable -> [Linkable]
- partitionLinkable li
- = let li_uls = linkableUnlinked li
- li_uls_obj = filter isObject li_uls
- li_uls_bco = filter isInterpretable li_uls
- in
- case (li_uls_obj, li_uls_bco) of
- (_:_, _:_) -> [li {linkableUnlinked=li_uls_obj},
- li {linkableUnlinked=li_uls_bco}]
- _ -> [li]
- findModuleLinkable_maybe :: [Linkable] -> Module -> Maybe Linkable
- findModuleLinkable_maybe lis mod
- = case [LM time nm us | LM time nm us <- lis, nm == mod] of
- [] -> Nothing
- [li] -> Just li
- _ -> pprPanic "findModuleLinkable" (ppr mod)
- linkableInSet :: Linkable -> [Linkable] -> Bool
- linkableInSet l objs_loaded =
- case findModuleLinkable_maybe objs_loaded (linkableModule l) of
- Nothing -> False
- Just m -> linkableTime l == linkableTime m
- \end{code}
- %************************************************************************
- %* *
- \subsection{The object-code linker}
- %* *
- %************************************************************************
- \begin{code}
- dynLinkObjs :: DynFlags -> PersistentLinkerState -> [Linkable]
- -> IO (PersistentLinkerState, SuccessFlag)
- dynLinkObjs dflags pls objs = do
- -- Load the object files and link them
- let (objs_loaded', new_objs) = rmDupLinkables (objs_loaded pls) objs
- pls1 = pls { objs_loaded = objs_loaded' }
- unlinkeds = concatMap linkableUnlinked new_objs
- mapM_ loadObj (map nameOfObject unlinkeds)
- -- Link the all together
- ok <- resolveObjs
- -- If resolving failed, unload all our
- -- object modules and carry on
- if succeeded ok then do
- return (pls1, Succeeded)
- else do
- pls2 <- unload_wkr dflags [] pls1
- return (pls2, Failed)
- rmDupLinkables :: [Linkable] -- Already loaded
- -> [Linkable] -- New linkables
- -> ([Linkable], -- New loaded set (including new ones)
- [Linkable]) -- New linkables (excluding dups)
- rmDupLinkables already ls
- = go already [] ls
- where
- go already extras [] = (already, extras)
- go already extras (l:ls)
- | linkableInSet l already = go already extras ls
- | otherwise = go (l:already) (l:extras) ls
- \end{code}
- %************************************************************************
- %* *
- \subsection{The byte-code linker}
- %* *
- %************************************************************************
- \begin{code}
- dynLinkBCOs :: PersistentLinkerState -> [Linkable] -> IO PersistentLinkerState
- dynLinkBCOs pls bcos = do
- let (bcos_loaded', new_bcos) = rmDupLinkables (bcos_loaded pls) bcos
- pls1 = pls { bcos_loaded = bcos_loaded' }
- unlinkeds :: [Unlinked]
- unlinkeds = concatMap linkableUnlinked new_bcos
- cbcs :: [CompiledByteCode]
- cbcs = map byteCodeOfObject unlinkeds
-
-
- ul_bcos = [b | ByteCode bs _ <- cbcs, b <- bs]
- ies = [ie | ByteCode _ ie <- cbcs]
- gce = closure_env pls
- final_ie = foldr plusNameEnv (itbl_env pls) ies
- (final_gce, _linked_bcos) <- linkSomeBCOs True final_ie gce ul_bcos
- -- XXX What happens to these linked_bcos?
- let pls2 = pls1 { closure_env = final_gce,
- itbl_env = final_ie }
- return pls2
- -- Link a bunch of BCOs and return them + updated closure env.
- linkSomeBCOs :: Bool -- False <=> add _all_ BCOs to returned closure env
- -- True <=> add only toplevel BCOs to closure env
- -> ItblEnv
- -> ClosureEnv
- -> [UnlinkedBCO]
- -> IO (ClosureEnv, [HValue])
- -- The returned HValues are associated 1-1 with
- -- the incoming unlinked BCOs. Each gives the
- -- value of the corresponding unlinked BCO
-
- linkSomeBCOs toplevs_only ie ce_in ul_bcos
- = do let nms = map unlinkedBCOName ul_bcos
- hvals <- fixIO
- ( \ hvs -> let ce_out = extendClosureEnv ce_in (zipLazy nms hvs)
- in mapM (linkBCO ie ce_out) ul_bcos )
- let ce_all_additions = zip nms hvals
- ce_top_additions = filter (isExternalName.fst) ce_all_additions
- ce_additions = if toplevs_only then ce_top_additions
- else ce_all_additions
- ce_out = -- make sure we're not inserting duplicate names into the
- -- closure environment, which leads to trouble.
- ASSERT (all (not . (`elemNameEnv` ce_in)) (map fst ce_additions))
- extendClosureEnv ce_in ce_additions
- return (ce_out, hvals)
- \end{code}
- %************************************************************************
- %* *
- Unload some object modules
- %* *
- %************************************************************************
- \begin{code}
- -- ---------------------------------------------------------------------------
- -- | Unloading old objects ready for a new compilation sweep.
- --
- -- The compilation manager provides us with a list of linkables that it
- -- considers \"stable\", i.e. won't be recompiled this time around. For
- -- each of the modules current linked in memory,
- --
- -- * if the linkable is stable (and it's the same one -- the user may have
- -- recompiled the module on the side), we keep it,
- --
- -- * otherwise, we unload it.
- --
- -- * we also implicitly unload all temporary bindings at this point.
- --
- unload :: DynFlags
- -> [Linkable] -- ^ The linkables to *keep*.
- -> IO ()
- unload dflags linkables
- = mask_ $ do -- mask, so we're safe from Ctrl-C in here
-
- -- Initialise the linker (if it's not been done already)
- initDynLinker dflags
- new_pls
- <- modifyMVar v_PersistentLinkerState $ \pls -> do
- pls1 <- unload_wkr dflags linkables pls
- return (pls1, pls1)
- debugTraceMsg dflags 3 (text "unload: retaining objs" <+> ppr (objs_loaded new_pls))
- debugTraceMsg dflags 3 (text "unload: retaining bcos" <+> ppr (bcos_loaded new_pls))
- return ()
- unload_wkr :: DynFlags
- -> [Linkable] -- stable linkables
- -> PersistentLinkerState
- -> IO PersistentLinkerState
- -- Does the core unload business
- -- (the wrapper blocks exceptions and deals with the PLS get and put)
- unload_wkr _ linkables pls
- = do let (objs_to_keep, bcos_to_keep) = partition isObjectLinkable linkables
- objs_loaded' <- filterM (maybeUnload objs_to_keep) (objs_loaded pls)
- bcos_loaded' <- filterM (maybeUnload bcos_to_keep) (bcos_loaded pls)
- let bcos_retained = map linkableModule bcos_loaded'
- itbl_env' = filterNameMap bcos_retained (itbl_env pls)
- closure_env' = filterNameMap bcos_retained (closure_env pls)
- new_pls = pls { itbl_env = itbl_env',
- closure_env = closure_env',
- bcos_loaded = bcos_loaded',
- objs_loaded = objs_loaded' }
- return new_pls
- where
- maybeUnload :: [Linkable] -> Linkable -> IO Bool
- maybeUnload keep_linkables lnk
- | linkableInSet lnk keep_linkables = return True
- | otherwise
- = do mapM_ unloadObj [f | DotO f <- linkableUnlinked lnk]
- -- The components of a BCO linkable may contain
- -- dot-o files. Which is very confusing.
- --
- -- But the BCO parts can be unlinked just by
- -- letting go of them (plus of course depopulating
- -- the symbol table which is done in the main body)
- return False
- \end{code}
- %************************************************************************
- %* *
- Loading packages
- %* *
- %************************************************************************
- \begin{code}
- data LibrarySpec
- = Object FilePath -- Full path name of a .o file, including trailing .o
- -- For dynamic objects only, try to find the object
- -- file in all the directories specified in
- -- v_Library_paths before giving up.
- | Archive FilePath -- Full path name of a .a file, including trailing .a
- | DLL String -- "Unadorned" name of a .DLL/.so
- -- e.g. On unix "qt" denotes "libqt.so"
- -- On WinDoze "burble" denotes "burble.DLL"
- -- loadDLL is platform-specific and adds the lib/.so/.DLL
- -- suffixes platform-dependently
- | DLLPath FilePath -- Absolute or relative pathname to a dynamic library
- -- (ends with .dll or .so).
- | Framework String -- Only used for darwin, but does no harm
- -- If this package is already part of the GHCi binary, we'll already
- -- have the right DLLs for this package loaded, so don't try to
- -- load them again.
- --
- -- But on Win32 we must load them 'again'; doing so is a harmless no-op
- -- as far as the loader is concerned, but it does initialise the list
- -- of DLL handles that rts/Linker.c maintains, and that in turn is
- -- used by lookupSymbol. So we must call addDLL for each library
- -- just to get the DLL handle into the list.
- partOfGHCi :: [PackageName]
- partOfGHCi
- | isWindowsTarget || isDarwinTarget = []
- | otherwise = map PackageName
- ["base", "template-haskell", "editline"]
- showLS :: LibrarySpec -> String
- showLS (Object nm) = "(static) " ++ nm
- showLS (Archive nm) = "(static archive) " ++ nm
- showLS (DLL nm) = "(dynamic) " ++ nm
- showLS (DLLPath nm) = "(dynamic) " ++ nm
- showLS (Framework nm) = "(framework) " ++ nm
- -- | Link exactly the specified packages, and their dependents (unless of
- -- course they are already linked). The dependents are linked
- -- automatically, and it doesn't matter what order you specify the input
- -- packages.
- --
- linkPackages :: DynFlags -> [PackageId] -> IO ()
- -- NOTE: in fact, since each module tracks all the packages it depends on,
- -- we don't really need to use the package-config dependencies.
- --
- -- However we do need the package-config stuff (to find aux libs etc),
- -- and following them lets us load libraries in the right order, which
- -- perhaps makes the error message a bit more localised if we get a link
- -- failure. So the dependency walking code is still here.
- linkPackages dflags new_pkgs = do
- -- It's probably not safe to try to load packages concurrently, so we take
- -- a lock.
- modifyMVar_ v_PersistentLinkerState $ \pls -> do
- linkPackages' dflags new_pkgs pls
- linkPackages' :: DynFlags -> [PackageId] -> PersistentLinkerState
- -> IO PersistentLinkerState
- linkPackages' dflags new_pks pls = do
- pkgs' <- link (pkgs_loaded pls) new_pks
- return $! pls { pkgs_loaded = pkgs' }
- where
- pkg_map = pkgIdMap (pkgState dflags)
- ipid_map = installedPackageIdMap (pkgState dflags)
- link :: [PackageId] -> [PackageId] -> IO [PackageId]
- link pkgs new_pkgs =
- foldM link_one pkgs new_pkgs
- link_one pkgs new_pkg
- | new_pkg `elem` pkgs -- Already linked
- = return pkgs
- | Just pkg_cfg <- lookupPackage pkg_map new_pkg
- = do { -- Link dependents first
- pkgs' <- link pkgs [ Maybes.expectJust "link_one" $
- Map.lookup ipid ipid_map
- | ipid <- depends pkg_cfg ]
- -- Now link the package itself
- ; linkPackage dflags pkg_cfg
- ; return (new_pkg : pkgs') }
- | otherwise
- = ghcError (CmdLineError ("unknown package: " ++ packageIdString new_pkg))
- linkPackage :: DynFlags -> PackageConfig -> IO ()
- linkPackage dflags pkg
- = do
- let dirs = Packages.libraryDirs pkg
- let libs = Packages.hsLibraries pkg
- -- The FFI GHCi import lib isn't needed as
- -- compiler/ghci/Linker.lhs + rts/Linker.c link the
- -- interpreted references to FFI to the compiled FFI.
- -- We therefore filter it out so that we don't get
- -- duplicate symbol errors.
- libs' = filter ("HSffi" /=) libs
- -- Because of slight differences between the GHC dynamic linker and
- -- the native system linker some packages have to link with a
- -- different list of libraries when using GHCi. Examples include: libs
- -- that are actually gnu ld scripts, and the possability that the .a
- -- libs do not exactly match the .so/.dll equivalents. So if the
- -- package file provides an "extra-ghci-libraries" field then we use
- -- that instead of the "extra-libraries" field.
- ++ (if null (Packages.extraGHCiLibraries pkg)
- then Packages.extraLibraries pkg
- else Packages.extraGHCiLibraries pkg)
- ++ [ lib | '-':'l':lib <- Packages.ldOptions pkg ]
- classifieds <- mapM (locateOneObj dirs) libs'
- -- Complication: all the .so's must be loaded before any of the .o's.
- let dlls = [ dll | DLL dll <- classifieds ]
- objs = [ obj | Object obj <- classifieds ]
- archs = [ arch | Archive arch <- classifieds ]
- maybePutStr dflags ("Loading package " ++ display (sourcePackageId pkg) ++ " ... ")
- -- See comments with partOfGHCi
- when (packageName pkg `notElem` partOfGHCi) $ do
- loadFrameworks pkg
- -- When a library A needs symbols from a library B, the order in
- -- extra_libraries/extra_ld_opts is "-lA -lB", because that's the
- -- way ld expects it for static linking. Dynamic linking is a
- -- different story: When A has no dependency information for B,
- -- dlopen-ing A with RTLD_NOW (see addDLL in Linker.c) will fail
- -- when B has not been loaded before. In a nutshell: Reverse the
- -- order of DLLs for dynamic linking.
- -- This fixes a problem with the HOpenGL package (see "Compiling
- -- HOpenGL under recent versions of GHC" on the HOpenGL list).
- mapM_ (load_dyn dirs) (reverse dlls)
-
- -- After loading all the DLLs, we can load the static objects.
- -- Ordering isn't important here, because we do one final link
- -- step to resolve everything.
- mapM_ loadObj objs
- mapM_ loadArchive archs
- maybePutStr dflags "linking ... "
- ok <- resolveObjs
- if succeeded ok then maybePutStrLn dflags "done."
- else ghcError (InstallationError ("unable to load package `" ++ display (sourcePackageId pkg) ++ "'"))
- load_dyn :: [FilePath] -> FilePath -> IO ()
- load_dyn dirs dll = do r <- loadDynamic dirs dll
- case r of
- Nothing -> return ()
- Just err -> ghcError (CmdLineError ("can't load .so/.DLL for: "
- ++ dll ++ " (" ++ err ++ ")" ))
- loadFrameworks :: InstalledPackageInfo_ ModuleName -> IO ()
- loadFrameworks pkg
- | isDarwinTarget = mapM_ load frameworks
- | otherwise = return ()
- where
- fw_dirs = Packages.frameworkDirs pkg
- frameworks = Packages.frameworks pkg
- load fw = do r <- loadFramework fw_dirs fw
- case r of
- Nothing -> return ()
- Just err -> ghcError (CmdLineError ("can't load framework: "
- ++ fw ++ " (" ++ err ++ ")" ))
- -- Try to find an object file for a given library in the given paths.
- -- If it isn't present, we assume it's a dynamic library.
- locateOneObj :: [FilePath] -> String -> IO LibrarySpec
- locateOneObj dirs lib
- | not ("HS" `isPrefixOf` lib)
- -- For non-Haskell libraries (e.g. gmp, iconv) we assume dynamic library
- = assumeDll
- | not isDynamicGhcLib
- -- When the GHC package was not compiled as dynamic library
- -- (=DYNAMIC not set), we search for .o libraries or, if they
- -- don't exist, .a libraries.
- = findObject `orElse` findArchive `orElse` assumeDll
- | otherwise
- -- When the GHC package was compiled as dynamic library (=DYNAMIC set),
- -- we search for .so libraries first.
- = findDll `orElse` findObject `orElse` findArchive `orElse` assumeDll
- where
- mk_obj_path dir = dir </> (lib <.> "o")
- mk_arch_path dir = dir </> ("lib" ++ lib <.> "a")
- dyn_lib_name = lib ++ "-ghc" ++ cProjectVersion
- mk_dyn_lib_path dir = dir </> mkSOName dyn_lib_name
- findObject = liftM (fmap Object) $ findFile mk_obj_path dirs
- findArchive = liftM (fmap Archive) $ findFile mk_arch_path dirs
- findDll = liftM (fmap DLL) $ findFile mk_dyn_lib_path dirs
- assumeDll = return (DLL lib)
- infixr `orElse`
- f `orElse` g = do m <- f
- case m of
- Just x -> return x
- Nothing -> g
- -- ----------------------------------------------------------------------------
- -- Loading a dyanmic library (dlopen()-ish on Unix, LoadLibrary-ish on Win32)
- -- return Nothing == success, else Just error message from dlopen
- loadDynamic :: [FilePath] -> FilePath -> IO (Maybe String)
- loadDynamic paths rootname
- = do { mb_dll <- findFile mk_dll_path paths
- ; case mb_dll of
- Just dll -> loadDLL dll
- Nothing -> loadDLL (mkSOName rootname) }
- -- Tried all our known library paths, so let
- -- dlopen() search its own builtin paths now.
- where
- mk_dll_path dir = dir </> mkSOName rootname
- mkSOName :: FilePath -> FilePath
- mkSOName root
- | isDarwinTarget = ("lib" ++ root) <.> "dylib"
- | isWindowsTarget = -- Win32 DLLs have no .dll extension here, because
- -- addDLL tries both foo.dll and foo.drv
- root
- | otherwise = ("lib" ++ root) <.> "so"
- -- Darwin / MacOS X only: load a framework
- -- a framework is a dynamic library packaged inside a directory of the same
- -- name. They are searched for in different paths than normal libraries.
- loadFramework :: [FilePath] -> FilePath -> IO (Maybe String)
- loadFramework extraPaths rootname
- = do { either_dir <- tryIO getHomeDirectory
- ; let homeFrameworkPath = case either_dir of
- Left _ -> []
- Right dir -> [dir ++ "/Library/Frameworks"]
- ps = extraPaths ++ homeFrameworkPath ++ defaultFrameworkPaths
- ; mb_fwk <- findFile mk_fwk ps
- ; case mb_fwk of
- Just fwk_path -> loadDLL fwk_path
- Nothing -> return (Just "not found") }
- -- Tried all our known library paths, but dlopen()
- -- has no built-in paths for frameworks: give up
- where
- mk_fwk dir = dir </> (rootname ++ ".framework/" ++ rootname)
- -- sorry for the hardcoded paths, I hope they won't change anytime soon:
- defaultFrameworkPaths = ["/Library/Frameworks", "/System/Library/Frameworks"]
- \end{code}
- %************************************************************************
- %* *
- Helper functions
- %* *
- %************************************************************************
- \begin{code}
- findFile :: (FilePath -> FilePath) -- Maps a directory path to a file path
- -> [FilePath] -- Directories to look in
- -> IO (Maybe FilePath) -- The first file path to match
- findFile _ []
- = return Nothing
- findFile mk_file_path (dir:dirs)
- = do { let file_path = mk_file_path dir
- ; b <- doesFileExist file_path
- ; if b then
- return (Just file_path)
- else
- findFile mk_file_path dirs }
- \end{code}
- \begin{code}
- maybePutStr :: DynFlags -> String -> IO ()
- maybePutStr dflags s | verbosity dflags > 0 = putStr s
- | otherwise = return ()
- maybePutStrLn :: DynFlags -> String -> IO ()
- maybePutStrLn dflags s | verbosity dflags > 0 = putStrLn s
- | otherwise = return ()
- \end{code}