FIX #2500: Don't log warnings in getHeader
[ghc.git] / compiler / main / HeaderInfo.hs
1 -----------------------------------------------------------------------------
2 --
3 -- | Parsing the top of a Haskell source file to get its module name,
4 -- imports and options.
5 --
6 -- (c) Simon Marlow 2005
7 -- (c) Lemmih 2006
8 --
9 -----------------------------------------------------------------------------
10
11 module HeaderInfo ( getImports
12 , getOptionsFromFile, getOptions
13 , optionsErrorMsgs,
14 checkProcessArgsResult ) where
15
16 #include "HsVersions.h"
17
18 import RdrName
19 import HscTypes
20 import Parser ( parseHeader )
21 import Lexer
22 import FastString
23 import HsSyn ( ImportDecl(..), HsModule(..) )
24 import Module ( ModuleName, moduleName )
25 import PrelNames ( gHC_PRIM, mAIN_NAME )
26 import StringBuffer
27 import SrcLoc
28 import DynFlags
29 import ErrUtils
30 import Util
31 import Outputable
32 import Pretty ()
33 import Maybes
34 import Bag ( emptyBag, listToBag, unitBag )
35
36 import MonadUtils ( MonadIO )
37 import Exception
38 import Control.Monad
39 import System.IO
40 import System.IO.Unsafe
41 import Data.List
42
43 ------------------------------------------------------------------------------
44
45 -- | Parse the imports of a source file.
46 --
47 -- Throws a 'SourceError' if parsing fails.
48 getImports :: GhcMonad m =>
49 DynFlags
50 -> StringBuffer -- ^ Parse this.
51 -> FilePath -- ^ Filename the buffer came from. Used for
52 -- reporting parse error locations.
53 -> FilePath -- ^ The original source filename (used for locations
54 -- in the function result)
55 -> m ([Located (ImportDecl RdrName)], [Located (ImportDecl RdrName)], Located ModuleName)
56 -- ^ The source imports, normal imports, and the module name.
57 getImports dflags buf filename source_filename = do
58 let loc = mkSrcLoc (mkFastString filename) 1 0
59 case unP parseHeader (mkPState buf loc dflags) of
60 PFailed span err -> parseError span err
61 POk pst rdr_module -> do
62 let ms@(_warns, errs) = getMessages pst
63 -- don't log warnings: they'll be reported when we parse the file
64 -- for real. See #2500.
65 -- logWarnings warns
66 if errorsFound dflags ms
67 then liftIO $ throwIO $ mkSrcErr errs
68 else
69 case rdr_module of
70 L _ (HsModule mb_mod _ imps _ _ _ _) ->
71 let
72 main_loc = mkSrcLoc (mkFastString source_filename) 1 0
73 mod = mb_mod `orElse` L (srcLocSpan main_loc) mAIN_NAME
74 (src_idecls, ord_idecls) = partition (ideclSource.unLoc) imps
75 ordinary_imps = filter ((/= moduleName gHC_PRIM) . unLoc . ideclName . unLoc)
76 ord_idecls
77 -- GHC.Prim doesn't exist physically, so don't go looking for it.
78 in
79 return (src_idecls, ordinary_imps, mod)
80
81 parseError :: GhcMonad m => SrcSpan -> Message -> m a
82 parseError span err = throwOneError $ mkPlainErrMsg span err
83
84 --------------------------------------------------------------
85 -- Get options
86 --------------------------------------------------------------
87
88 -- | Parse OPTIONS and LANGUAGE pragmas of the source file.
89 --
90 -- Throws a 'SourceError' if flag parsing fails (including unsupported flags.)
91 getOptionsFromFile :: DynFlags
92 -> FilePath -- ^ Input file
93 -> IO [Located String] -- ^ Parsed options, if any.
94 getOptionsFromFile dflags filename
95 = Exception.bracket
96 (openBinaryFile filename ReadMode)
97 (hClose)
98 (\handle -> do
99 opts <- fmap getOptions' $ lazyGetToks dflags filename handle
100 seqList opts $ return opts)
101
102 blockSize :: Int
103 -- blockSize = 17 -- for testing :-)
104 blockSize = 1024
105
106 lazyGetToks :: DynFlags -> FilePath -> Handle -> IO [Located Token]
107 lazyGetToks dflags filename handle = do
108 buf <- hGetStringBufferBlock handle blockSize
109 unsafeInterleaveIO $ lazyLexBuf handle (pragState dflags buf loc) False
110 where
111 loc = mkSrcLoc (mkFastString filename) 1 0
112
113 lazyLexBuf :: Handle -> PState -> Bool -> IO [Located Token]
114 lazyLexBuf handle state eof = do
115 case unP (lexer return) state of
116 POk state' t -> do
117 -- pprTrace "lazyLexBuf" (text (show (buffer state'))) (return ())
118 if atEnd (buffer state') && not eof
119 -- if this token reached the end of the buffer, and we haven't
120 -- necessarily read up to the end of the file, then the token might
121 -- be truncated, so read some more of the file and lex it again.
122 then getMore handle state
123 else case t of
124 L _ ITeof -> return [t]
125 _other -> do rest <- lazyLexBuf handle state' eof
126 return (t : rest)
127 _ | not eof -> getMore handle state
128 | otherwise -> return [L (last_loc state) ITeof]
129 -- parser assumes an ITeof sentinel at the end
130
131 getMore :: Handle -> PState -> IO [Located Token]
132 getMore handle state = do
133 -- pprTrace "getMore" (text (show (buffer state))) (return ())
134 nextbuf <- hGetStringBufferBlock handle blockSize
135 if (len nextbuf == 0) then lazyLexBuf handle state True else do
136 newbuf <- appendStringBuffers (buffer state) nextbuf
137 unsafeInterleaveIO $ lazyLexBuf handle state{buffer=newbuf} False
138
139
140 getToks :: DynFlags -> FilePath -> StringBuffer -> [Located Token]
141 getToks dflags filename buf = lexAll (pragState dflags buf loc)
142 where
143 loc = mkSrcLoc (mkFastString filename) 1 0
144
145 lexAll state = case unP (lexer return) state of
146 POk _ t@(L _ ITeof) -> [t]
147 POk state' t -> t : lexAll state'
148 _ -> [L (last_loc state) ITeof]
149
150
151 -- | Parse OPTIONS and LANGUAGE pragmas of the source file.
152 --
153 -- Throws a 'SourceError' if flag parsing fails (including unsupported flags.)
154 getOptions :: DynFlags
155 -> StringBuffer -- ^ Input Buffer
156 -> FilePath -- ^ Source filename. Used for location info.
157 -> [Located String] -- ^ Parsed options.
158 getOptions dflags buf filename
159 = getOptions' (getToks dflags filename buf)
160
161 -- The token parser is written manually because Happy can't
162 -- return a partial result when it encounters a lexer error.
163 -- We want to extract options before the buffer is passed through
164 -- CPP, so we can't use the same trick as 'getImports'.
165 getOptions' :: [Located Token] -- Input buffer
166 -> [Located String] -- Options.
167 getOptions' toks
168 = parseToks toks
169 where
170 getToken (L _loc tok) = tok
171 getLoc (L loc _tok) = loc
172
173 parseToks (open:close:xs)
174 | IToptions_prag str <- getToken open
175 , ITclose_prag <- getToken close
176 = map (L (getLoc open)) (words str) ++
177 parseToks xs
178 parseToks (open:close:xs)
179 | ITinclude_prag str <- getToken open
180 , ITclose_prag <- getToken close
181 = map (L (getLoc open)) ["-#include",removeSpaces str] ++
182 parseToks xs
183 parseToks (open:close:xs)
184 | ITdocOptions str <- getToken open
185 , ITclose_prag <- getToken close
186 = map (L (getLoc open)) ["-haddock-opts", removeSpaces str]
187 ++ parseToks xs
188 parseToks (open:xs)
189 | ITdocOptionsOld str <- getToken open
190 = map (L (getLoc open)) ["-haddock-opts", removeSpaces str]
191 ++ parseToks xs
192 parseToks (open:xs)
193 | ITlanguage_prag <- getToken open
194 = parseLanguage xs
195 parseToks _ = []
196 parseLanguage (L loc (ITconid fs):rest)
197 = checkExtension (L loc fs) :
198 case rest of
199 (L _loc ITcomma):more -> parseLanguage more
200 (L _loc ITclose_prag):more -> parseToks more
201 (L loc _):_ -> languagePragParseError loc
202 [] -> panic "getOptions'.parseLanguage(1) went past eof token"
203 parseLanguage (tok:_)
204 = languagePragParseError (getLoc tok)
205 parseLanguage []
206 = panic "getOptions'.parseLanguage(2) went past eof token"
207
208 -----------------------------------------------------------------------------
209
210 -- | Complain about non-dynamic flags in OPTIONS pragmas.
211 --
212 -- Throws a 'SourceError' if the input list is non-empty claiming that the
213 -- input flags are unknown.
214 checkProcessArgsResult :: MonadIO m => [Located String] -> m ()
215 checkProcessArgsResult flags
216 = when (notNull flags) $
217 liftIO $ throwIO $ mkSrcErr $ listToBag $ map mkMsg flags
218 where mkMsg (L loc flag)
219 = mkPlainErrMsg loc $
220 (text "unknown flag in {-# OPTIONS #-} pragma:" <+>
221 text flag)
222
223 -----------------------------------------------------------------------------
224
225 checkExtension :: Located FastString -> Located String
226 checkExtension (L l ext)
227 -- Checks if a given extension is valid, and if so returns
228 -- its corresponding flag. Otherwise it throws an exception.
229 = let ext' = unpackFS ext in
230 if ext' `elem` supportedLanguages
231 || ext' `elem` (map ("No"++) supportedLanguages)
232 then L l ("-X"++ext')
233 else unsupportedExtnError l ext'
234
235 languagePragParseError :: SrcSpan -> a
236 languagePragParseError loc =
237 throw $ mkSrcErr $ unitBag $
238 (mkPlainErrMsg loc $
239 text "cannot parse LANGUAGE pragma: comma-separated list expected")
240
241 unsupportedExtnError :: SrcSpan -> String -> a
242 unsupportedExtnError loc unsup =
243 throw $ mkSrcErr $ unitBag $
244 mkPlainErrMsg loc $
245 text "unsupported extension: " <> text unsup
246
247
248 optionsErrorMsgs :: [String] -> [Located String] -> FilePath -> Messages
249 optionsErrorMsgs unhandled_flags flags_lines _filename
250 = (emptyBag, listToBag (map mkMsg unhandled_flags_lines))
251 where unhandled_flags_lines = [ L l f | f <- unhandled_flags,
252 L l f' <- flags_lines, f == f' ]
253 mkMsg (L flagSpan flag) =
254 ErrUtils.mkPlainErrMsg flagSpan $
255 text "unknown flag in {-# OPTIONS #-} pragma:" <+> text flag
256