diff options
Diffstat (limited to 'compiler/GHC/Data/StringBuffer.hs')
| -rw-r--r-- | compiler/GHC/Data/StringBuffer.hs | 14 |
1 files changed, 14 insertions, 0 deletions
diff --git a/compiler/GHC/Data/StringBuffer.hs b/compiler/GHC/Data/StringBuffer.hs index 03d720eb37..e6dcb14b6b 100644 --- a/compiler/GHC/Data/StringBuffer.hs +++ b/compiler/GHC/Data/StringBuffer.hs @@ -26,6 +26,7 @@ module GHC.Data.StringBuffer hPutStringBuffer, appendStringBuffers, stringToStringBuffer, + stringBufferFromByteString, -- * Inspection nextChar, @@ -68,6 +69,10 @@ import System.IO.Unsafe ( unsafePerformIO ) import GHC.IO.Encoding.UTF8 ( mkUTF8 ) import GHC.IO.Encoding.Failure ( CodingFailureMode(IgnoreCodingFailure) ) +import qualified Data.ByteString.Internal as BS +import qualified Data.ByteString as BS +import Data.ByteString ( ByteString ) + import GHC.Exts import Foreign @@ -199,6 +204,15 @@ stringToStringBuffer str = -- sentinels for UTF-8 decoding return (StringBuffer buf size 0) +-- | Convert a UTF-8 encoded 'ByteString' into a 'StringBuffer. This really +-- relies on the internals of both 'ByteString' and 'StringBuffer'. +-- +-- /O(n)/ (but optimized into a @memcpy@ by @bytestring@ under the hood) +stringBufferFromByteString :: ByteString -> StringBuffer +stringBufferFromByteString bs = + let BS.PS fp off len = BS.append bs (BS.pack [0,0,0]) + in StringBuffer { buf = fp, len = len - 3, cur = off } + -- ----------------------------------------------------------------------------- -- Grab a character |