2 % (c) The University of Glasgow, 2000
4 \section[CompManager]{The Compilation Manager}
7 module CompManager ( cmInit, cmLoadModule, cmUnload,
11 CmState, emptyCmState -- abstract
15 #include "HsVersions.h"
20 import Module ( Module, ModuleName, moduleName, isHomeModule,
21 mkModuleName, moduleNameUserString )
22 import CmStaticInfo ( GhciMode(..) )
25 import HscTypes ( HomeSymbolTable, HomeIfaceTable,
26 PersistentCompilerState, ModDetails(..) )
27 import HscMain ( initPersistentCompilerState )
29 import UniqFM ( emptyUFM, lookupUFM, addToUFM, delListFromUFM,
31 import Unique ( Uniquable )
32 import Digraph ( SCC(..), stronglyConnComp, flattenSCC )
33 import DriverFlags ( getDynFlags )
35 import DriverUtil ( splitFilename3 )
36 import ErrUtils ( showPass )
41 import CmdLineOpts ( DynFlags(..) )
45 import Interpreter ( HValue )
46 import HscMain ( hscExpr )
48 import PrelGHC ( unsafeCoerce# )
52 import Exception ( throwDyn )
55 import Time ( ClockTime )
56 import Directory ( getModificationTime, doesFileExist )
60 import Maybe ( catMaybes, fromMaybe, isJust, fromJust )
65 cmInit :: GhciMode -> IO CmState
72 -> Bool -- True <=> wrap in 'print' to get an IO-typed result
75 -> IO (CmState, Maybe (HValue, PrintUnqualified, Type))
76 cmGetExpr cmstate dflags wrap_io mod expr
77 = do (new_pcs, maybe_stuff) <-
78 hscExpr dflags wrap_io hst hit pcs mod expr
80 Nothing -> return (cmstate{ pcs=new_pcs }, Nothing)
81 Just (bcos, print_unqual, ty) -> do
82 hValue <- linkExpr pls bcos
83 return (cmstate{ pcs=new_pcs },
84 Just (hValue, print_unqual, ty))
86 -- ToDo: check that the module we passed in is sane/exists?
88 CmState{ hst=hst, hit=hit, pcs=pcs, pls=pls } = cmstate
90 -- The HValue should represent a value of type IO () (Perhaps IO a?)
91 cmRunExpr :: HValue -> IO ()
93 = do unsafeCoerce# hval :: IO ()
97 emptyHIT :: HomeIfaceTable
99 emptyHST :: HomeSymbolTable
102 -- Persistent state for the entire system
105 hst :: HomeSymbolTable, -- home symbol table
106 hit :: HomeIfaceTable, -- home interface table
107 ui :: UnlinkedImage, -- the unlinked images
108 mg :: ModuleGraph, -- the module graph
109 gmode :: GhciMode, -- NEVER CHANGES
111 pcs :: PersistentCompilerState, -- compile's persistent state
112 pls :: PersistentLinkerState -- link's persistent state
115 emptyCmState :: GhciMode -> IO CmState
117 = do pcs <- initPersistentCompilerState
119 return (CmState { hst = emptyHST,
128 type UnlinkedImage = [Linkable] -- the unlinked images (should be a set, really)
129 emptyUI :: UnlinkedImage
132 type ModuleGraph = [ModSummary] -- the module graph, topologically sorted
133 emptyMG :: ModuleGraph
138 Unload the compilation manager's state: everything it knows about the
139 current collection of modules in the Home package.
142 cmUnload :: CmState -> IO CmState
144 = do -- Throw away the old home dir cache
146 -- Throw away the HIT and the HST
147 return state{ hst=new_hst, hit=new_hit, ui=emptyUI }
149 CmState{ hst=hst, hit=hit } = state
150 (new_hst, new_hit) = retainInTopLevelEnvs [] (hst,hit)
153 The real business of the compilation manager: given a system state and
154 a module name, try and bring the module up to date, probably changing
155 the system state at the same time.
158 cmLoadModule :: CmState
160 -> IO (CmState, -- new state
161 Bool, -- was successful
162 [Module]) -- list of modules loaded
164 cmLoadModule cmstate1 rootname
165 = do -- version 1's are the original, before downsweep
166 let pls1 = pls cmstate1
167 let pcs1 = pcs cmstate1
168 let hst1 = hst cmstate1
169 let hit1 = hit cmstate1
170 -- similarly, ui1 is the (complete) set of linkables from
171 -- the previous pass, if any.
172 let ui1 = ui cmstate1
173 let mg1 = mg cmstate1
175 let ghci_mode = gmode cmstate1 -- this never changes
177 -- Do the downsweep to reestablish the module graph
178 -- then generate version 2's by retaining in HIT,HST,UI a
179 -- stable set S of modules, as defined below.
181 dflags <- getDynFlags
182 let verb = verbosity dflags
184 showPass dflags "Chasing dependencies"
185 when (verb >= 1 && ghci_mode == Batch) $
186 hPutStrLn stderr (progName ++ ": chasing modules from: " ++ rootname)
188 (mg2unsorted, a_root_is_Main) <- downsweep [rootname] mg1
189 let mg2unsorted_names = map name_of_summary mg2unsorted
191 -- reachable_from follows source as well as normal imports
192 let reachable_from :: ModuleName -> [ModuleName]
193 reachable_from = downwards_closure_of_module mg2unsorted
195 -- should be cycle free; ignores 'import source's
196 let mg2 = topological_sort False mg2unsorted
197 -- ... whereas this takes them into account. Used for
198 -- backing out partially complete cycles following a failed
199 -- upsweep, and for removing from hst/hit all the modules
200 -- not in strict downwards closure, during calls to compile.
201 let mg2_with_srcimps = topological_sort True mg2unsorted
203 -- Sort out which linkables we wish to keep in the unlinked image.
204 -- For each module, we take:
206 -- - the old in-core linkable, if available
207 -- - an on-disk linkable, if available
209 -- and we take the youngest of these, provided it is younger than the
212 -- If a module has a valid linkable, then it may be STABLE (see below),
213 -- and it is classified as SOURCE UNCHANGED for the purposes of calling
215 valid_linkables <- getValidLinkables ui1 mg2unsorted
217 -- Figure out a stable set of modules which can be retained
218 -- the top level envs, to avoid upsweeping them. Goes to a
219 -- bit of trouble to avoid upsweeping module cycles.
221 -- Construct a set S of stable modules like this:
222 -- Travel upwards, over the sccified graph. For each scc
223 -- of modules ms, add ms to S only if:
224 -- 1. All home imports of ms are either in ms or S
225 -- 2. A valid linkable exists for each module in ms
228 <- preUpsweep valid_linkables ui1 mg2unsorted_names
232 = concatMap (findInSummaries mg2unsorted) stable_mods
235 = filter (\m -> linkableModName m `elem` stable_mods)
239 putStrLn (showSDoc (text "STABLE MODULES:"
240 <+> sep (map (text.moduleNameUserString) stable_mods)))
242 -- unload any modules which aren't going to be re-linked this
244 pls2 <- unload ghci_mode dflags stable_linkables pls1
246 -- We could at this point detect cycles which aren't broken by
247 -- a source-import, and complain immediately, but it seems better
248 -- to let upsweep_mods do this, so at least some useful work gets
249 -- done before the upsweep is abandoned.
251 = filter (\scc -> any (`notElem` stable_mods)
252 (map name_of_summary (flattenSCC scc)))
255 --hPutStrLn stderr "after tsort:\n"
256 --hPutStrLn stderr (showSDoc (vcat (map ppr mg2)))
258 -- Because we don't take into account source imports when doing
259 -- the topological sort, there shouldn't be any cycles in mg2.
260 -- If there is, we complain and give up -- the user needs to
261 -- break the cycle using a boot file.
263 -- Now do the upsweep, calling compile for each module in
264 -- turn. Final result is version 3 of everything.
266 let threaded2 = CmThreaded pcs1 hst1 hit1
268 (upsweep_complete_success, threaded3, modsUpswept, newLis)
269 <- upsweep_mods ghci_mode dflags valid_linkables reachable_from
270 threaded2 upsweep_these
272 let ui3 = add_to_ui valid_linkables newLis
273 let (CmThreaded pcs3 hst3 hit3) = threaded3
275 -- At this point, modsUpswept and newLis should have the same
276 -- length, so there is one new (or old) linkable for each
277 -- mod which was processed (passed to compile).
279 -- Make modsDone be the summaries for each home module now
280 -- available; this should equal the domains of hst3 and hit3.
281 -- (NOT STRICTLY TRUE if an interactive session was started
282 -- with some object on disk ???)
283 -- Get in in a roughly top .. bottom order (hence reverse).
285 let modsDone = reverse modsUpswept ++ stable_summaries
287 -- Try and do linking in some form, depending on whether the
288 -- upsweep was completely or only partially successful.
290 if upsweep_complete_success
293 -- Easy; just relink it all.
294 do when (verb >= 2) $
295 hPutStrLn stderr "Upsweep completely successful."
297 <- link ghci_mode dflags a_root_is_Main ui3 pls2
300 -> panic "cmLoadModule: link failed (1)"
303 = CmState { hst=hst3, hit=hit3,
307 return (cmstate3, True,
311 -- Tricky. We need to back out the effects of compiling any
312 -- half-done cycles, both so as to clean up the top level envs
313 -- and to avoid telling the interactive linker to link them.
314 do when (verb >= 2) $
315 hPutStrLn stderr "Upsweep partially successful."
318 = map name_of_summary modsDone
319 let mods_to_zap_names
320 = findPartiallyCompletedCycles modsDone_names mg2_with_srcimps
321 let (hst4, hit4, ui4)
322 = removeFromTopLevelEnvs mods_to_zap_names (hst3,hit3,ui3)
324 = filter ((`notElem` mods_to_zap_names).name_of_summary) modsDone
325 let mods_to_keep_names
326 = map name_of_summary mods_to_keep
327 -- we could get the relevant linkables by filtering newLis, but
328 -- it seems easier to drag them out of the updated, cleaned-up UI
329 let linkables_to_link
330 = map (unJust "linkables_to_link" . findModuleLinkable_maybe ui4)
333 linkresult <- link ghci_mode dflags False linkables_to_link pls2
336 -> panic "cmLoadModule: link failed (2)"
339 = CmState { hst=hst4, hit=hit4,
340 ui=ui4, mg=mods_to_keep,
341 gmode=ghci_mode, pcs=pcs3, pls=pls3 }
342 return (cmstate4, False,
343 map ms_mod mods_to_keep)
346 -----------------------------------------------------------------------------
350 :: [Linkable] -- old linkables
351 -> [ModSummary] -- all modules in the program
352 -> IO [Linkable] -- still-valid linkables
354 getValidLinkables old_linkables summaries
355 = do lis <- mapM (getValidLinkable old_linkables) summaries
358 getValidLinkable old_linkables summary
359 = do let mod_name = moduleName (ms_mod summary)
361 <- case ml_obj_file (ms_location summary) of
362 Nothing -> return Nothing
363 Just obj_fn -> maybe_getFileLinkable mod_name obj_fn
365 -- find an old in-core linkable if we have one. (forget about
366 -- on-disk linkables for now, we'll check again whether there's
367 -- one here below, just in case a new one has popped up recently).
368 let old_linkable = findModuleLinkable_maybe old_linkables mod_name
371 Just (LM _ _ ls) | all isInterpretable ls -> old_linkable
374 -- The most recent of the old UI linkable or whatever we could
375 -- find on disk is returned as the linkable if compile
376 -- doesn't think we need to recompile.
378 = case (maybe_old_linkable, maybe_disk_linkable) of
379 (Nothing, Nothing) -> []
380 (Nothing, Just di) -> [di]
381 (Just ui, Nothing) -> [ui]
383 | linkableTime ui >= linkableTime di -> [ui]
386 -- only linkables newer than the source code are valid
387 let maybe_src_date = ms_hs_date summary
390 = case maybe_src_date of
391 Nothing -> panic "valid_linkable_list"
393 -> filter (\li -> linkableTime li > src_date) linkable_list
395 return valid_linkable_list
399 maybe_getFileLinkable :: ModuleName -> FilePath -> IO (Maybe Linkable)
400 maybe_getFileLinkable mod_name obj_fn
401 = do obj_exist <- doesFileExist obj_fn
405 do let stub_fn = case splitFilename3 obj_fn of
406 (dir, base, ext) -> dir ++ "/" ++ base ++ ".stub_o"
407 stub_exist <- doesFileExist stub_fn
408 obj_time <- getModificationTime obj_fn
410 then return (Just (LM obj_time mod_name [DotO obj_fn, DotO stub_fn]))
411 else return (Just (LM obj_time mod_name [DotO obj_fn]))
414 -----------------------------------------------------------------------------
415 -- Do a pre-upsweep without use of "compile", to establish a
416 -- (downward-closed) set of stable modules for which we won't call compile.
418 preUpsweep :: [Linkable] -- new valid linkables
419 -> [Linkable] -- old linkables
420 -> [ModuleName] -- names of all mods encountered in downsweep
421 -> [ModuleName] -- accumulating stable modules
422 -> [SCC ModSummary] -- scc-ified mod graph, including src imps
423 -> IO [ModuleName] -- stable modules
425 preUpsweep valid_lis old_lis all_home_mods stable []
427 preUpsweep valid_lis old_lis all_home_mods stable (scc0:sccs)
428 = do let scc = flattenSCC scc0
429 scc_allhomeimps :: [ModuleName]
431 = nub (filter (`elem` all_home_mods) (concatMap ms_allimps scc))
432 all_imports_in_scc_or_stable
433 = all in_stable_or_scc scc_allhomeimps
435 = map name_of_summary scc
437 = --trace (showSDoc (text "ISOS" <+> ppr m <+> ppr scc_names <+> ppr stable)) (
438 m `elem` scc_names || m `elem` stable
441 -- now we check for valid linkables: each module in the SCC must
442 -- have a valid linkable (see getValidLinkables above), and the
443 -- newest linkable must be the same as the previous linkable for
444 -- this module (if one exists).
445 has_valid_linkable new_summary
446 = case findModuleLinkable_maybe valid_lis modname of
448 Just l -> case findModuleLinkable_maybe old_lis modname of
450 Just m -> linkableTime l == linkableTime m
451 where modname = name_of_summary new_summary
453 scc_is_stable = all_imports_in_scc_or_stable
454 && all has_valid_linkable scc
457 then preUpsweep valid_lis old_lis all_home_mods
458 (scc_names++stable) sccs
459 else preUpsweep valid_lis old_lis all_home_mods
465 -- Helper for preUpsweep. Assuming that new_summary's imports are all
466 -- stable (in the sense of preUpsweep), determine if new_summary is itself
467 -- stable, and, if so, in batch mode, return its linkable.
468 findInSummaries :: [ModSummary] -> ModuleName -> [ModSummary]
469 findInSummaries old_summaries mod_name
470 = [s | s <- old_summaries, name_of_summary s == mod_name]
472 findModInSummaries :: [ModSummary] -> Module -> Maybe ModSummary
473 findModInSummaries old_summaries mod
474 = case [s | s <- old_summaries, ms_mod s == mod] of
478 -- Return (names of) all those in modsDone who are part of a cycle
479 -- as defined by theGraph.
480 findPartiallyCompletedCycles :: [ModuleName] -> [SCC ModSummary] -> [ModuleName]
481 findPartiallyCompletedCycles modsDone theGraph
485 chew ((AcyclicSCC v):rest) = chew rest -- acyclic? not interesting.
486 chew ((CyclicSCC vs):rest)
487 = let names_in_this_cycle = nub (map name_of_summary vs)
489 = nub ([done | done <- modsDone,
490 done `elem` names_in_this_cycle])
491 chewed_rest = chew rest
493 if not (null mods_in_this_cycle)
494 && length mods_in_this_cycle < length names_in_this_cycle
495 then mods_in_this_cycle ++ chewed_rest
499 -- Add the given (LM-form) Linkables to the UI, overwriting previous
500 -- versions if they exist.
501 add_to_ui :: UnlinkedImage -> [Linkable] -> UnlinkedImage
503 = filter (not_in lis) ui ++ lis
505 not_in :: [Linkable] -> Linkable -> Bool
507 = all (\l -> linkableModName l /= mod) lis
508 where mod = linkableModName li
511 data CmThreaded -- stuff threaded through individual module compilations
512 = CmThreaded PersistentCompilerState HomeSymbolTable HomeIfaceTable
515 -- Compile multiple modules, stopping as soon as an error appears.
516 -- There better had not be any cyclic groups here -- we check for them.
517 upsweep_mods :: GhciMode
519 -> UnlinkedImage -- valid linkables
520 -> (ModuleName -> [ModuleName]) -- to construct downward closures
521 -> CmThreaded -- PCS & HST & HIT
522 -> [SCC ModSummary] -- mods to do (the worklist)
523 -- ...... RETURNING ......
524 -> IO (Bool{-complete success?-},
526 [ModSummary], -- mods which succeeded
527 [Linkable]) -- new linkables
529 upsweep_mods ghci_mode dflags oldUI reachable_from threaded
531 = return (True, threaded, [], [])
533 upsweep_mods ghci_mode dflags oldUI reachable_from threaded
535 = do hPutStrLn stderr ("Module imports form a cycle for modules:\n\t" ++
536 unwords (map (moduleNameUserString.name_of_summary) ms))
537 return (False, threaded, [], [])
539 upsweep_mods ghci_mode dflags oldUI reachable_from threaded
540 ((AcyclicSCC mod):mods)
541 = do --case threaded of
542 -- CmThreaded pcsz hstz hitz
543 -- -> putStrLn ("UPSWEEP_MOD: hit = " ++ show (map (moduleNameUserString.moduleName.mi_module) (eltsUFM hitz)))
545 (threaded1, maybe_linkable)
546 <- upsweep_mod ghci_mode dflags oldUI threaded mod
547 (reachable_from (name_of_summary mod))
548 case maybe_linkable of
550 -> -- No errors; do the rest
551 do (restOK, threaded2, modOKs, linkables)
552 <- upsweep_mods ghci_mode dflags oldUI reachable_from
554 return (restOK, threaded2, mod:modOKs, linkable:linkables)
555 Nothing -- we got a compilation error; give up now
556 -> return (False, threaded1, [], [])
559 -- Compile a single module. Always produce a Linkable for it if
560 -- successful. If no compilation happened, return the old Linkable.
561 upsweep_mod :: GhciMode
567 -> IO (CmThreaded, Maybe Linkable)
569 upsweep_mod ghci_mode dflags oldUI threaded1 summary1 reachable_from_here
571 let mod_name = name_of_summary summary1
572 let verb = verbosity dflags
575 if (ghci_mode == Batch)
576 then hPutStr stderr (progName ++ ": module "
577 ++ moduleNameUserString mod_name
579 else hPutStr stderr ("Compiling "
580 ++ moduleNameUserString mod_name
583 let (CmThreaded pcs1 hst1 hit1) = threaded1
584 let old_iface = lookupUFM hit1 mod_name
586 let maybe_old_linkable = findModuleLinkable_maybe oldUI mod_name
588 source_unchanged = isJust maybe_old_linkable
590 (hst1_strictDC, hit1_strictDC)
591 = retainInTopLevelEnvs
592 (filter (/= (name_of_summary summary1)) reachable_from_here)
596 = unJust "upsweep_mod:old_linkable" maybe_old_linkable
598 compresult <- compile ghci_mode summary1 source_unchanged
599 old_iface hst1_strictDC hit1_strictDC pcs1
603 -- Compilation "succeeded", but didn't return a new
604 -- linkable, meaning that compilation wasn't needed, and the
605 -- new details were manufactured from the old iface.
606 CompOK pcs2 new_details new_iface Nothing
607 -> do let hst2 = addToUFM hst1 mod_name new_details
608 hit2 = addToUFM hit1 mod_name new_iface
609 threaded2 = CmThreaded pcs2 hst2 hit2
611 if ghci_mode == Interactive && verb >= 1 then
612 -- if we're using an object file, tell the user
614 (LM _ _ objs@(DotO _:_))
615 -> do hPutStrLn stderr (showSDoc (space <>
616 parens (hsep (text "using":
618 [ text o | DotO o <- objs ]))))
623 return (threaded2, Just old_linkable)
625 -- Compilation really did happen, and succeeded. A new
626 -- details, iface and linkable are returned.
627 CompOK pcs2 new_details new_iface (Just new_linkable)
628 -> do let hst2 = addToUFM hst1 mod_name new_details
629 hit2 = addToUFM hit1 mod_name new_iface
630 threaded2 = CmThreaded pcs2 hst2 hit2
632 return (threaded2, Just new_linkable)
634 -- Compilation failed. compile may still have updated
637 -> do let threaded2 = CmThreaded pcs2 hst1 hit1
638 return (threaded2, Nothing)
640 -- Remove unwanted modules from the top level envs (HST, HIT, UI).
641 removeFromTopLevelEnvs :: [ModuleName]
642 -> (HomeSymbolTable, HomeIfaceTable, UnlinkedImage)
643 -> (HomeSymbolTable, HomeIfaceTable, UnlinkedImage)
644 removeFromTopLevelEnvs zap_these (hst, hit, ui)
645 = (delListFromUFM hst zap_these,
646 delListFromUFM hit zap_these,
647 filterModuleLinkables (`notElem` zap_these) ui
650 retainInTopLevelEnvs :: [ModuleName]
651 -> (HomeSymbolTable, HomeIfaceTable)
652 -> (HomeSymbolTable, HomeIfaceTable)
653 retainInTopLevelEnvs keep_these (hst, hit)
654 = (retainInUFM hst keep_these,
655 retainInUFM hit keep_these
658 retainInUFM :: Uniquable key => UniqFM elt -> [key] -> UniqFM elt
659 retainInUFM ufm keys_to_keep
660 = listToUFM (concatMap (maybeLookupUFM ufm) keys_to_keep)
662 = case lookupUFM ufm u of Nothing -> []; Just val -> [(u, val)]
664 -- Needed to clean up HIT and HST so that we don't get duplicates in inst env
665 downwards_closure_of_module :: [ModSummary] -> ModuleName -> [ModuleName]
666 downwards_closure_of_module summaries root
667 = let toEdge :: ModSummary -> (ModuleName,[ModuleName])
668 toEdge summ = (name_of_summary summ, ms_allimps summ)
669 res = simple_transitive_closure (map toEdge summaries) [root]
671 --trace (showSDoc (text "DC of mod" <+> ppr root
672 -- <+> text "=" <+> ppr res)) (
676 -- Calculate transitive closures from a set of roots given an adjacency list
677 simple_transitive_closure :: Eq a => [(a,[a])] -> [a] -> [a]
678 simple_transitive_closure graph set
679 = let set2 = nub (concatMap dsts set ++ set)
680 dsts node = fromMaybe [] (lookup node graph)
682 if length set == length set2
684 else simple_transitive_closure graph set2
687 -- Calculate SCCs of the module graph, with or without taking into
688 -- account source imports.
689 topological_sort :: Bool -> [ModSummary] -> [SCC ModSummary]
690 topological_sort include_source_imports summaries
692 toEdge :: ModSummary -> (ModSummary,ModuleName,[ModuleName])
694 = (summ, name_of_summary summ,
695 (if include_source_imports
696 then ms_srcimps summ else []) ++ ms_imps summ)
698 mash_edge :: (ModSummary,ModuleName,[ModuleName]) -> (ModSummary,Int,[Int])
699 mash_edge (summ, m, m_imports)
700 = case lookup m key_map of
701 Nothing -> panic "reverse_topological_sort"
702 Just mk -> (summ, mk,
703 -- ignore imports not from the home package
704 catMaybes (map (flip lookup key_map) m_imports))
706 edges = map toEdge summaries
707 key_map = zip [nm | (s,nm,imps) <- edges] [1 ..] :: [(ModuleName,Int)]
708 scc_input = map mash_edge edges
709 sccs = stronglyConnComp scc_input
714 -- Chase downwards from the specified root set, returning summaries
715 -- for all home modules encountered. Only follow source-import
716 -- links. Also returns a Bool to indicate whether any of the roots
718 downsweep :: [FilePath] -> [ModSummary] -> IO ([ModSummary], Bool)
719 downsweep rootNm old_summaries
720 = do rootSummaries <- mapM getRootSummary rootNm
722 = any ((=="Main").moduleNameUserString.name_of_summary)
725 <- loop (concat (map ms_imps rootSummaries))
726 (filter (isHomeModule.ms_mod) rootSummaries)
727 return (all_summaries, a_root_is_Main)
729 getRootSummary :: FilePath -> IO ModSummary
731 | haskellish_file file
732 = do exists <- doesFileExist file
733 if exists then summariseFile file else do
734 throwDyn (OtherError ("can't find file `" ++ file ++ "'"))
736 = do exists <- doesFileExist hs_file
737 if exists then summariseFile hs_file else do
738 exists <- doesFileExist lhs_file
739 if exists then summariseFile lhs_file else do
740 getSummary (mkModuleName file)
742 hs_file = file ++ ".hs"
743 lhs_file = file ++ ".lhs"
745 getSummaries :: ModuleName -> IO ModSummary
747 -- | trace ("getSummary: "++ showSDoc (ppr nm)) True
748 = do found <- findModule nm
750 -- Be sure not to use the mod and location passed in to
751 -- summarise for any other purpose -- summarise may change
752 -- the module names in them if name of module /= name of file,
753 -- and put the changed versions in the returned summary.
754 -- These will then conflict with the passed-in versions.
755 Just (mod, location) -> do
756 let old_summary = findModInSummaries old_summaries mod
757 new_summary <- summarise mod location old_summary
759 Nothing -> return (fromJust old_summary)
762 Nothing -> throwDyn (OtherError
763 ("can't find module `"
764 ++ showSDoc (ppr nm) ++ "'"))
766 -- loop invariant: home_summaries doesn't contain package modules
767 loop :: [ModuleName] -> [ModSummary] -> IO [ModSummary]
768 loop [] home_summaries = return home_summaries
769 loop imps home_summaries
770 = do -- all modules currently in homeSummaries
771 let all_home = map (moduleName.ms_mod) home_summaries
773 -- imports for modules we don't already have
774 let needed_imps = filter (`notElem` all_home) imps
777 needed_summaries <- mapM getSummary needed_imps
779 -- get just the "home" modules
780 let new_home_summaries
781 = filter (isHomeModule.ms_mod) needed_summaries
783 -- loop, checking the new imports
784 let new_imps = concat (map ms_imps new_home_summaries)
785 loop new_imps (new_home_summaries ++ home_summaries)
787 -----------------------------------------------------------------------------
788 -- Summarising modules
790 -- We have two types of summarisation:
792 -- * Summarise a file. This is used for the root module passed to
793 -- cmLoadModule. The file is read, and used to determine the root
794 -- module name. The module name may differ from the filename.
796 -- * Summarise a module. We are given a module name, and must provide
797 -- a summary. The finder is used to locate the file in which the module
800 summariseFile :: FilePath -> IO ModSummary
802 = do hspp_fn <- preprocess file
803 modsrc <- readFile hspp_fn
805 let (srcimps,imps,mod_name) = getImports modsrc
806 (path, basename, ext) = splitFilename3 file
809 <- mkHomeModuleLocn mod_name (path ++ '/':basename) file
812 <- case ml_hs_file location of
813 Nothing -> return Nothing
814 Just src_fn -> maybe_getModificationTime src_fn
816 return (ModSummary mod
817 location{ml_hspp_file=Just hspp_fn}
821 -- Summarise a module, and pick up source and timestamp.
822 summarise :: Module -> ModuleLocation -> Maybe ModSummary
823 -> IO (Maybe ModSummary)
824 summarise mod location old_summary
826 = do let hs_fn = unJust "summarise" (ml_hs_file location)
829 <- case ml_hs_file location of
830 Nothing -> return Nothing
831 Just src_fn -> maybe_getModificationTime src_fn
833 -- return the cached summary if the source didn't change
834 case old_summary of {
835 Just s | ms_hs_date s == maybe_src_timestamp -> return Nothing;
838 hspp_fn <- preprocess hs_fn
839 modsrc <- readFile hspp_fn
840 let (srcimps,imps,mod_name) = getImports modsrc
843 <- case ml_hs_file location of
844 Nothing -> return Nothing
845 Just src_fn -> maybe_getModificationTime src_fn
847 if mod_name == moduleName mod
849 else throwDyn (OtherError
850 (showSDoc (text "file name does not match module name: "
851 <+> ppr (moduleName mod) <+> text "vs"
854 return (Just (ModSummary mod location{ml_hspp_file=Just hspp_fn}
856 maybe_src_timestamp))
860 = return (Just (ModSummary mod location [] [] Nothing))
862 maybe_getModificationTime :: FilePath -> IO (Maybe ClockTime)
863 maybe_getModificationTime fn
864 = (do time <- getModificationTime fn
867 (\err -> return Nothing)