summaryrefslogtreecommitdiff
path: root/compiler/main/Packages.lhs
blob: 1bafe6cf66d1f2baa988544e392746decf047368 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
 %
% (c) The University of Glasgow, 2006
%
% Package manipulation
%
\begin{code}
module Packages (
	module PackageConfig,

	-- * The PackageConfigMap
	PackageConfigMap, emptyPackageConfigMap, lookupPackage,
	extendPackageConfigMap,	dumpPackages,

	-- * Reading the package config, and processing cmdline args
	PackageState(..),
	initPackages,
	getPackageDetails,
	lookupModuleInAllPackages,

	-- * Inspecting the set of packages in scope
	getPackageIncludePath,
	getPackageLibraryPath,
	getPackageLinkOpts,
	getPackageExtraCcOpts,
	getPackageFrameworkPath,
	getPackageFrameworks,
	getPreloadPackagesAnd,

        collectIncludeDirs, collectLibraryPaths, collectLinkOpts,

	-- * Utils
	isDllName
    )
where

#include "HsVersions.h"

import PackageConfig	
import ParsePkgConf	( loadPackageConfig )
import DynFlags		( dopt, DynFlag(..), DynFlags(..), PackageFlag(..) )
import StaticFlags	( opt_Static )
import Config		( cProjectVersion )
import Name		( Name, nameModule_maybe )
import UniqFM
import Module
import Util
import Maybes		( expectJust, MaybeErr(..) )
import Panic
import Outputable

import System.Environment ( getEnv )
import Distribution.InstalledPackageInfo hiding (depends)
import Distribution.Package hiding (depends)
import Distribution.Text
import Distribution.Version
import FastString
import ErrUtils         ( debugTraceMsg, putMsg, Message )

import System.Directory
import System.FilePath
import Data.Maybe
import Control.Monad
import Data.List

-- ---------------------------------------------------------------------------
-- The Package state

-- Package state is all stored in DynFlags, including the details of
-- all packages, which packages are exposed, and which modules they
-- provide.

-- The package state is computed by initPackages, and kept in DynFlags.
--
--   * -package <pkg> causes <pkg> to become exposed, and all other packages 
--	with the same name to become hidden.
-- 
--   * -hide-package <pkg> causes <pkg> to become hidden.
-- 
--   * Let exposedPackages be the set of packages thus exposed.  
--     Let depExposedPackages be the transitive closure from exposedPackages of
--     their dependencies.
--
--   * When searching for a module from an preload import declaration,
--     only the exposed modules in exposedPackages are valid.
--
--   * When searching for a module from an implicit import, all modules
--     from depExposedPackages are valid.
--
--   * When linking in a comp manager mode, we link in packages the
--     program depends on (the compiler knows this list by the
--     time it gets to the link step).  Also, we link in all packages
--     which were mentioned with preload -package flags on the command-line,
--     or are a transitive dependency of same, or are "base"/"rts".
--     The reason for (b) is that we might need packages which don't
--     contain any Haskell modules, and therefore won't be discovered
--     by the normal mechanism of dependency tracking.

-- Notes on DLLs
-- ~~~~~~~~~~~~~
-- When compiling module A, which imports module B, we need to 
-- know whether B will be in the same DLL as A.  
-- 	If it's in the same DLL, we refer to B_f_closure
-- 	If it isn't, we refer to _imp__B_f_closure
-- When compiling A, we record in B's Module value whether it's
-- in a different DLL, by setting the DLL flag.

data PackageState = PackageState {
  pkgIdMap		:: PackageConfigMap, -- PackageId   -> PackageConfig
	-- The exposed flags are adjusted according to -package and
	-- -hide-package flags, and -ignore-package removes packages.

  preloadPackages      :: [PackageId],
	-- The packages we're going to link in eagerly.  This list
	-- should be in reverse dependency order; that is, a package
	-- is always mentioned before the packages it depends on.

  moduleToPkgConfAll 	:: UniqFM [(PackageConfig,Bool)] -- ModuleEnv mapping
	-- Derived from pkgIdMap.	
	-- Maps Module to (pkgconf,exposed), where pkgconf is the
	-- PackageConfig for the package containing the module, and
	-- exposed is True if the package exposes that module.
  }

-- A PackageConfigMap maps a PackageId to a PackageConfig
type PackageConfigMap = UniqFM PackageConfig

emptyPackageConfigMap :: PackageConfigMap
emptyPackageConfigMap = emptyUFM

lookupPackage :: PackageConfigMap -> PackageId -> Maybe PackageConfig
lookupPackage = lookupUFM

extendPackageConfigMap
   :: PackageConfigMap -> [PackageConfig] -> PackageConfigMap
extendPackageConfigMap pkg_map new_pkgs 
  = foldl add pkg_map new_pkgs
  where add pkg_map p = addToUFM pkg_map (packageConfigId p) p

getPackageDetails :: PackageState -> PackageId -> PackageConfig
getPackageDetails ps pid = expectJust "getPackageDetails" (lookupPackage (pkgIdMap ps) pid)

-- ----------------------------------------------------------------------------
-- Loading the package config files and building up the package state

-- | Call this after 'DynFlags.parseDynFlags'.  It reads the package
-- configuration files, and sets up various internal tables of package
-- information, according to the package-related flags on the
-- command-line (@-package@, @-hide-package@ etc.)
--
-- Returns a list of packages to link in if we're doing dynamic linking.
-- This list contains the packages that the user explicitly mentioned with
-- -package flags.
--
-- 'initPackages' can be called again subsequently after updating the
-- 'packageFlags' field of the 'DynFlags', and it will update the
-- 'packageState' in 'DynFlags' and return a list of packages to
-- link in.
initPackages :: DynFlags -> IO (DynFlags, [PackageId])
initPackages dflags = do 
  pkg_db <- case pkgDatabase dflags of
                Nothing -> readPackageConfigs dflags
                Just db -> return db
  (pkg_state, preload, this_pkg)       
        <- mkPackageState dflags pkg_db [] (thisPackage dflags)
  return (dflags{ pkgDatabase = Just pkg_db,
		  pkgState = pkg_state,
                  thisPackage = this_pkg },
          preload)

-- -----------------------------------------------------------------------------
-- Reading the package database(s)

readPackageConfigs :: DynFlags -> IO PackageConfigMap
readPackageConfigs dflags = do
   e_pkg_path <- try (getEnv "GHC_PACKAGE_PATH")
   system_pkgconfs <- getSystemPackageConfigs dflags

   let pkgconfs = case e_pkg_path of
		    Left _   -> system_pkgconfs
		    Right path
		     | last cs == "" -> init cs ++ system_pkgconfs
		     | otherwise     -> cs
		     where cs = parseSearchPath path
		     -- if the path ends in a separator (eg. "/foo/bar:")
		     -- the we tack on the system paths.

	-- Read all the ones mentioned in -package-conf flags
   pkg_map <- foldM (readPackageConfig dflags) emptyPackageConfigMap
		 (reverse pkgconfs ++ extraPkgConfs dflags)

   return pkg_map


getSystemPackageConfigs :: DynFlags -> IO [FilePath]
getSystemPackageConfigs dflags = do
	-- System one always comes first
   let system_pkgconf = systemPackageConfig dflags

	-- allow package.conf.d to contain a bunch of .conf files
	-- containing package specifications.  This is an easier way
	-- to maintain the package database on systems with a package
	-- management system, or systems that don't want to run ghc-pkg
	-- to register or unregister packages.  Undocumented feature for now.
   let system_pkgconf_dir = system_pkgconf <.> "d"
   system_pkgconf_dir_exists <- doesDirectoryExist system_pkgconf_dir
   system_pkgconfs <-
     if system_pkgconf_dir_exists
       then do files <- getDirectoryContents system_pkgconf_dir
               return [ system_pkgconf_dir </> file
                      | file <- files
                      , takeExtension file == ".conf" ]
       else return []

	-- Read user's package conf (eg. ~/.ghc/i386-linux-6.3/package.conf)
	-- unless the -no-user-package-conf flag was given.
	-- We only do this when getAppUserDataDirectory is available 
	-- (GHC >= 6.3).
   user_pkgconf <- handle (\_ -> return []) $ do
      appdir <- getAppUserDataDirectory "ghc"
      let 
     	 pkgconf = appdir
		   </> (TARGET_ARCH ++ '-':TARGET_OS ++ '-':cProjectVersion)
		   </> "package.conf"
      flg <- doesFileExist pkgconf
      if (flg && dopt Opt_ReadUserPackageConf dflags)
	then return [pkgconf]
	else return []

   return (user_pkgconf ++ system_pkgconfs ++ [system_pkgconf])


readPackageConfig
   :: DynFlags -> PackageConfigMap -> FilePath -> IO PackageConfigMap
readPackageConfig dflags pkg_map conf_file = do
  debugTraceMsg dflags 2 (text "Using package config file:" <+> text conf_file)
  proto_pkg_configs <- loadPackageConfig dflags conf_file
  let top_dir = topDir dflags
      pkg_configs1 = mungePackagePaths top_dir proto_pkg_configs
      pkg_configs2 = maybeHidePackages dflags pkg_configs1
  return (extendPackageConfigMap pkg_map pkg_configs2)

maybeHidePackages :: DynFlags -> [PackageConfig] -> [PackageConfig]
maybeHidePackages dflags pkgs
  | dopt Opt_HideAllPackages dflags = map hide pkgs
  | otherwise 			    = pkgs
  where
    hide pkg = pkg{ exposed = False }

mungePackagePaths :: String -> [PackageConfig] -> [PackageConfig]
-- Replace the string "$topdir" at the beginning of a path
-- with the current topdir (obtained from the -B option).
mungePackagePaths top_dir ps = map munge_pkg ps
 where 
  munge_pkg p = p{ importDirs  = munge_paths (importDirs p),
		   includeDirs = munge_paths (includeDirs p),
    		   libraryDirs = munge_paths (libraryDirs p),
		   frameworkDirs = munge_paths (frameworkDirs p),
                   haddockInterfaces = munge_paths (haddockInterfaces p),
	           haddockHTMLs = munge_paths (haddockHTMLs p)
                    }

  munge_paths = map munge_path

  munge_path p 
	  | Just p' <- maybePrefixMatch "$topdir"     p =            top_dir ++ p'
	  | Just p' <- maybePrefixMatch "$httptopdir" p = toHttpPath top_dir ++ p'
	  | otherwise				    = p

  toHttpPath p = "file:///" ++ p


-- -----------------------------------------------------------------------------
-- Modify our copy of the package database based on a package flag
-- (-package, -hide-package, -ignore-package).

applyPackageFlag
   :: [PackageConfig]           -- Initial database
   -> PackageFlag               -- flag to apply
   -> IO [PackageConfig]        -- new database

applyPackageFlag pkgs flag = 
  case flag of
        ExposePackage str ->
	   case matchingPackages str pkgs of
		Nothing -> missingPackageErr str
		Just ([], _) -> panic "applyPackageFlag"
		Just (p:ps,qs) -> return (p':ps')
		  where p' = p {exposed=True}
		        ps' = hideAll (pkgName (package p)) (ps++qs)

	HidePackage str ->
           case matchingPackages str pkgs of
                Nothing -> missingPackageErr str
                Just (ps,qs) -> return (map hide ps ++ qs)
		  where hide p = p {exposed=False}

	IgnorePackage str ->
           case matchingPackages str pkgs of
                Nothing -> return pkgs
                Just (_, qs) -> return qs
		-- missing package is not an error for -ignore-package,
		-- because a common usage is to -ignore-package P as
		-- a preventative measure just in case P exists.
   where
	-- When a package is requested to be exposed, we hide all other
	-- packages with the same name.
	hideAll name ps = map maybe_hide ps
	  where maybe_hide p | pkgName (package p) == name = p {exposed=False}
			     | otherwise                   = p


matchingPackages :: String -> [PackageConfig]
         -> Maybe ([PackageConfig], [PackageConfig])
matchingPackages str pkgs
  = case partition (matches str) pkgs of
	([],_)    -> Nothing
	(ps,rest) -> Just (sortByVersion ps, rest)
  where
        -- A package named on the command line can either include the
	-- version, or just the name if it is unambiguous.
	matches str p
		=  str == display (package p)
		|| str == display (pkgName (package p))

pickPackages :: [PackageConfig] -> [String] -> [PackageConfig]
pickPackages pkgs strs = 
  [ p | p <- strs, Just (p:_, _) <- [matchingPackages p pkgs] ]

sortByVersion :: [InstalledPackageInfo_ m] -> [InstalledPackageInfo_ m]
sortByVersion = sortBy (flip (comparing (pkgVersion.package)))

comparing :: Ord a => (t -> a) -> t -> t -> Ordering
comparing f a b = f a `compare` f b

-- -----------------------------------------------------------------------------
-- Hide old versions of packages

--
-- hide all packages for which there is also a later version
-- that is already exposed.  This just makes it non-fatal to have two
-- versions of a package exposed, which can happen if you install a
-- later version of a package in the user database, for example.
--
hideOldPackages :: DynFlags -> [PackageConfig] -> IO [PackageConfig]
hideOldPackages dflags pkgs = mapM maybe_hide pkgs
  where maybe_hide p
	   | not (exposed p) = return p
	   | (p' : _) <- later_versions = do
		debugTraceMsg dflags 2 $
		   (ptext (sLit "hiding package") <+> 
                    text (display (package p)) <+>
		    ptext (sLit "to avoid conflict with later version") <+>
		    text (display (package p')))
		return (p {exposed=False})
	   | otherwise = return p
	  where myname = pkgName (package p)
		myversion = pkgVersion (package p)
		later_versions = [ p | p <- pkgs, exposed p,
				    let pkg = package p,
				    pkgName pkg == myname,
				    pkgVersion pkg > myversion ]

-- -----------------------------------------------------------------------------
-- Wired-in packages

findWiredInPackages
   :: DynFlags
   -> [PackageConfig]           -- database
   -> [PackageIdentifier]       -- preload packages
   -> PackageId 		-- this package
   -> IO ([PackageConfig],
          [PackageIdentifier],
          PackageId)

findWiredInPackages dflags pkgs preload this_package = do
  --
  -- Now we must find our wired-in packages, and rename them to
  -- their canonical names (eg. base-1.0 ==> base).
  --
  let
        wired_in_pkgids :: [(PackageId, [String])]
        wired_in_pkgids = [ (primPackageId, [""]),
                            (integerPackageId, [""]),
                            (basePackageId, [""]),
                            (rtsPackageId, [""]),
                            (haskell98PackageId, [""]),
                            (thPackageId, [""]),
                            (dphSeqPackageId, [""]),
                            (dphParPackageId, [""]),
                            (ndpPackageId, ["-seq", "-par"]) ]

        matches :: PackageConfig -> (PackageId, [String]) -> Bool
        pc `matches` (pid, suffixes)
            = display (pkgName (package pc)) `elem`
              (map (packageIdString pid ++) suffixes)

	-- find which package corresponds to each wired-in package
	-- delete any other packages with the same name
	-- update the package and any dependencies to point to the new
	-- one.
        --
        -- When choosing which package to map to a wired-in package
        -- name, we prefer exposed packages, and pick the latest
        -- version.  To override the default choice, -hide-package
        -- could be used to hide newer versions.
        --
	findWiredInPackage :: [PackageConfig] -> (PackageId, [String])
			   -> IO (Maybe (PackageIdentifier, PackageId))
	findWiredInPackage pkgs wired_pkg =
           let all_ps = [ p | p <- pkgs, p `matches` wired_pkg ] in
	   case filter exposed all_ps of
		[] -> case all_ps of
                        []   -> notfound
                        many -> pick (head (sortByVersion many))
		many  -> pick (head (sortByVersion many))
          where
                suffixes = snd wired_pkg
                notfound = do
			  debugTraceMsg dflags 2 $
			    ptext (sLit "wired-in package ")
				 <> ppr (fst wired_pkg)
                                 <> (if null suffixes
                                     then empty
                                     else text (show suffixes))
				 <> ptext (sLit " not found.")
			  return Nothing
		pick :: InstalledPackageInfo_ ModuleName
                     -> IO (Maybe (PackageIdentifier, PackageId))
                pick pkg = do
                        debugTraceMsg dflags 2 $
			    ptext (sLit "wired-in package ")
				 <> ppr (fst wired_pkg)
				 <> ptext (sLit " mapped to ")
				 <> text (display (package pkg))
			return (Just (package pkg, fst wired_pkg))


  mb_wired_in_ids <- mapM (findWiredInPackage pkgs) wired_in_pkgids
  let 
        wired_in_ids = catMaybes mb_wired_in_ids

	deleteOtherWiredInPackages pkgs = filterOut bad pkgs
	  where bad p = any (p `matches`) wired_in_pkgids
                     && package p `notElem` map fst wired_in_ids

	updateWiredInDependencies pkgs = map upd_pkg pkgs
	  where upd_pkg p = p{ package = upd_pid (package p),
			       depends = map upd_pid (depends p) }

	upd_pid pid = case filter ((== pid) . fst) wired_in_ids of
				[] -> pid
				((x, y):_) -> x{ pkgName = PackageName (packageIdString y),
                                                 pkgVersion = Version [] [] }

        pkgs1 = deleteOtherWiredInPackages pkgs

        pkgs2 = updateWiredInDependencies pkgs1

        preload1 = map upd_pid preload

        -- we must return an updated thisPackage, just in case we
        -- are actually compiling one of the wired-in packages
        Just old_this_pkg = unpackPackageId this_package
        new_this_pkg = mkPackageId (upd_pid old_this_pkg)

  return (pkgs2, preload1, new_this_pkg)

-- ----------------------------------------------------------------------------
--
-- Detect any packages that have missing dependencies, and also any
-- mutually-recursive groups of packages (loops in the package graph
-- are not allowed).  We do this by taking the least fixpoint of the
-- dependency graph, repeatedly adding packages whose dependencies are
-- satisfied until no more can be added.
--
elimDanglingDeps
   :: DynFlags
   -> [PackageConfig]
   -> [PackageId]       -- ignored packages
   -> IO [PackageConfig]

elimDanglingDeps dflags pkgs ignored = go [] pkgs'
 where
   pkgs' = filter (\p -> packageConfigId p `notElem` ignored) pkgs

   go avail not_avail =
     case partitionWith (depsAvailable avail) not_avail of
        ([],        not_avail) -> do mapM_ reportElim not_avail; return avail
        (new_avail, not_avail) -> go (new_avail ++ avail) (map fst not_avail)

   depsAvailable :: [PackageConfig] -> PackageConfig
                 -> Either PackageConfig (PackageConfig, [PackageIdentifier])
   depsAvailable pkgs_ok pkg 
        | null dangling = Left pkg
        | otherwise     = Right (pkg, dangling)
        where dangling = filter (`notElem` pids) (depends pkg)
              pids = map package pkgs_ok

   reportElim (p, deps) = 
        debugTraceMsg dflags 2 $
             (ptext (sLit "package") <+> pprPkg p <+> 
                  ptext (sLit "will be ignored due to missing or recursive dependencies:") $$ 
	      nest 2 (hsep (map (text.display) deps)))

-- -----------------------------------------------------------------------------
-- When all the command-line options are in, we can process our package
-- settings and populate the package state.

mkPackageState
    :: DynFlags
    -> PackageConfigMap         -- initial database
    -> [PackageId]              -- preloaded packages
    -> PackageId                -- this package
    -> IO (PackageState,
           [PackageId],         -- new packages to preload
           PackageId) -- this package, might be modified if the current

                      -- package is a wired-in package.

mkPackageState dflags orig_pkg_db preload0 this_package = do
  --
  -- Modify the package database according to the command-line flags
  -- (-package, -hide-package, -ignore-package, -hide-all-packages).
  --
  let flags = reverse (packageFlags dflags)
  let pkgs0 = eltsUFM orig_pkg_db
  pkgs1 <- foldM applyPackageFlag pkgs0 flags

  -- Here we build up a set of the packages mentioned in -package
  -- flags on the command line; these are called the "preload"
  -- packages.  we link these packages in eagerly.  The preload set
  -- should contain at least rts & base, which is why we pretend that
  -- the command line contains -package rts & -package base.
  --
  let new_preload_packages = 
        map package (pickPackages pkgs0 [ p | ExposePackage p <- flags ])

  -- hide packages that are subsumed by later versions
  pkgs2 <- hideOldPackages dflags pkgs1

  -- sort out which packages are wired in
  (pkgs3, preload1, new_this_pkg)
        <- findWiredInPackages dflags pkgs2 new_preload_packages this_package

  let ignored = map packageConfigId $
                   pickPackages pkgs0 [ p | IgnorePackage p <- flags ]
  pkgs <- elimDanglingDeps dflags pkgs3 ignored

  let pkg_db = extendPackageConfigMap emptyPackageConfigMap pkgs

      -- add base & rts to the preload packages
      basicLinkedPackages
       | dopt Opt_AutoLinkPackages dflags
          = filter (flip elemUFM pkg_db) [basePackageId, rtsPackageId]
       | otherwise = []
      -- but in any case remove the current package from the set of
      -- preloaded packages so that base/rts does not end up in the
      -- set up preloaded package when we are just building it
      preload2 = nub (filter (/= new_this_pkg)
		             (basicLinkedPackages ++ map mkPackageId preload1))

  -- Close the preload packages with their dependencies
  dep_preload <- closeDeps pkg_db (zip preload2 (repeat Nothing))
  let new_dep_preload = filter (`notElem` preload0) dep_preload

  let pstate = PackageState{ preloadPackages     = dep_preload,
		             pkgIdMap   	 = pkg_db,
		             moduleToPkgConfAll  = mkModuleMap pkg_db
		           }

  return (pstate, new_dep_preload, new_this_pkg)


-- -----------------------------------------------------------------------------
-- Make the mapping from module to package info

mkModuleMap
  :: PackageConfigMap
  -> UniqFM [(PackageConfig, Bool)]
mkModuleMap pkg_db = foldr extend_modmap emptyUFM pkgids
  where
        pkgids = map packageConfigId (eltsUFM pkg_db)
        
	extend_modmap pkgid modmap =
		addListToUFM_C (++) modmap 
		   ([(m, [(pkg, True)])  | m <- exposed_mods] ++
		    [(m, [(pkg, False)]) | m <- hidden_mods])
	  where
		pkg = expectJust "mkModuleMap" (lookupPackage pkg_db pkgid)
	        exposed_mods = exposedModules pkg
	        hidden_mods  = hiddenModules pkg

pprPkg :: PackageConfig -> SDoc
pprPkg p = text (display (package p))

-- -----------------------------------------------------------------------------
-- Extracting information from the packages in scope

-- Many of these functions take a list of packages: in those cases,
-- the list is expected to contain the "dependent packages",
-- i.e. those packages that were found to be depended on by the
-- current module/program.  These can be auto or non-auto packages, it
-- doesn't really matter.  The list is always combined with the list
-- of preload (command-line) packages to determine which packages to
-- use.

getPackageIncludePath :: DynFlags -> [PackageId] -> IO [String]
getPackageIncludePath dflags pkgs =
  collectIncludeDirs `fmap` getPreloadPackagesAnd dflags pkgs

collectIncludeDirs :: [PackageConfig] -> [FilePath] 
collectIncludeDirs ps = nub (filter notNull (concatMap includeDirs ps))

getPackageLibraryPath :: DynFlags -> [PackageId] -> IO [String]
getPackageLibraryPath dflags pkgs =
  collectLibraryPaths `fmap` getPreloadPackagesAnd dflags pkgs

collectLibraryPaths :: [PackageConfig] -> [FilePath]
collectLibraryPaths ps = nub (filter notNull (concatMap libraryDirs ps))

getPackageLinkOpts :: DynFlags -> [PackageId] -> IO [String]
getPackageLinkOpts dflags pkgs = 
  collectLinkOpts dflags `fmap` getPreloadPackagesAnd dflags pkgs

collectLinkOpts :: DynFlags -> [PackageConfig] -> [String]
collectLinkOpts dflags ps = concat (map all_opts ps)
  where
        tag = buildTag dflags
        rts_tag = rtsBuildTag dflags

	mkDynName | opt_Static = id
		  | otherwise = (++ ("-ghc" ++ cProjectVersion))
      	libs p     = map (mkDynName . addSuffix) (hsLibraries p)
      	                 ++ extraLibraries p
	all_opts p = map ("-l" ++) (libs p) ++ ldOptions p

        addSuffix rts@"HSrts"    = rts       ++ (expandTag rts_tag)
        addSuffix other_lib      = other_lib ++ (expandTag tag)

        expandTag t | null t = ""
		    | otherwise = '_':t

getPackageExtraCcOpts :: DynFlags -> [PackageId] -> IO [String]
getPackageExtraCcOpts dflags pkgs = do
  ps <- getPreloadPackagesAnd dflags pkgs
  return (concatMap ccOptions ps)

getPackageFrameworkPath  :: DynFlags -> [PackageId] -> IO [String]
getPackageFrameworkPath dflags pkgs = do
  ps <- getPreloadPackagesAnd dflags pkgs
  return (nub (filter notNull (concatMap frameworkDirs ps)))

getPackageFrameworks  :: DynFlags -> [PackageId] -> IO [String]
getPackageFrameworks dflags pkgs = do
  ps <- getPreloadPackagesAnd dflags pkgs
  return (concatMap frameworks ps)

-- -----------------------------------------------------------------------------
-- Package Utils

-- | Takes a Module, and if the module is in a package returns 
-- @(pkgconf,exposed)@ where pkgconf is the PackageConfig for that package,
-- and exposed is True if the package exposes the module.
lookupModuleInAllPackages :: DynFlags -> ModuleName -> [(PackageConfig,Bool)]
lookupModuleInAllPackages dflags m =
  case lookupUFM (moduleToPkgConfAll (pkgState dflags)) m of
	Nothing -> []
	Just ps -> ps

getPreloadPackagesAnd :: DynFlags -> [PackageId] -> IO [PackageConfig]
getPreloadPackagesAnd dflags pkgids =
  let 
      state   = pkgState dflags
      pkg_map = pkgIdMap state
      preload = preloadPackages state
      pairs = zip pkgids (repeat Nothing)
  in do
  all_pkgs <- throwErr (foldM (add_package pkg_map) preload pairs)
  return (map (getPackageDetails state) all_pkgs)

-- Takes a list of packages, and returns the list with dependencies included,
-- in reverse dependency order (a package appears before those it depends on).
closeDeps :: PackageConfigMap -> [(PackageId, Maybe PackageId)]
        -> IO [PackageId]
closeDeps pkg_map ps = throwErr (closeDepsErr pkg_map ps)

throwErr :: MaybeErr Message a -> IO a
throwErr m = case m of
		Failed e    -> ghcError (CmdLineError (showSDoc e))
		Succeeded r -> return r

closeDepsErr :: PackageConfigMap -> [(PackageId,Maybe PackageId)]
	-> MaybeErr Message [PackageId]
closeDepsErr pkg_map ps = foldM (add_package pkg_map) [] ps

-- internal helper
add_package :: PackageConfigMap -> [PackageId] -> (PackageId,Maybe PackageId)
	-> MaybeErr Message [PackageId]
add_package pkg_db ps (p, mb_parent)
  | p `elem` ps = return ps	-- Check if we've already added this package
  | otherwise =
      case lookupPackage pkg_db p of
        Nothing -> Failed (missingPackageMsg (packageIdString p) <> 
                           missingDependencyMsg mb_parent)
        Just pkg -> do
    	   -- Add the package's dependents also
	   let deps = map mkPackageId (depends pkg)
    	   ps' <- foldM (add_package pkg_db) ps (zip deps (repeat (Just p)))
    	   return (p : ps')

missingPackageErr :: String -> IO [PackageConfig]
missingPackageErr p = ghcError (CmdLineError (showSDoc (missingPackageMsg p)))

missingPackageMsg :: String -> SDoc
missingPackageMsg p = ptext (sLit "unknown package:") <+> text p

missingDependencyMsg :: Maybe PackageId -> SDoc
missingDependencyMsg Nothing = empty
missingDependencyMsg (Just parent)
  = space <> parens (ptext (sLit "dependency of") <+> ftext (packageIdFS parent))

-- -----------------------------------------------------------------------------

isDllName :: PackageId -> Name -> Bool
isDllName this_pkg name
  | opt_Static = False
  | Just mod <- nameModule_maybe name = modulePackageId mod /= this_pkg
  | otherwise = False  -- no, it is not even an external name

-- -----------------------------------------------------------------------------
-- Displaying packages

dumpPackages :: DynFlags -> IO ()
-- Show package info on console, if verbosity is >= 3
dumpPackages dflags
  = do  let pkg_map = pkgIdMap (pkgState dflags)
	putMsg dflags $
              vcat (map (text . showInstalledPackageInfo
                              . packageConfigToInstalledPackageInfo)
                        (eltsUFM pkg_map))
\end{code}