Add --debug option. Closes: #627499

This takes advantage of the debug logging done by missingh, and I added
my own debug messages for executeFile calls. There are still some other
low-level ways git-annex runs stuff that are not shown by debugging,
but this gets most of it easily.

Options.hs

@@ -8,6 +8,8 @@
 module Options where
 
 import System.Console.GetOpt
+import System.Log.Logger
+import Control.Monad.State (liftIO)
 
 import qualified Annex
 import Types
@@ -27,7 +29,9 @@ commonOptions =
 	, Option ['q'] ["quiet"] (NoArg (setquiet True))
 		"avoid verbose output"
 	, Option ['v'] ["verbose"] (NoArg (setquiet False))
-		"allow verbose output"
+		"allow verbose output (default)"
+	, Option ['d'] ["debug"] (NoArg (setdebug))
+		"show debug messages"
 	, Option ['b'] ["backend"] (ReqArg setforcebackend paramName)
 		"specify key-value backend to use"
 	]
@@ -36,3 +40,4 @@ commonOptions =
 		setfast v = Annex.changeState $ \s -> s { Annex.fast = v }
 		setquiet v = Annex.changeState $ \s -> s { Annex.quiet = v }
 		setforcebackend v = Annex.changeState $ \s -> s { Annex.forcebackend = Just v }
+		setdebug = liftIO $ updateGlobalLogger "" $ setLevel DEBUG

Remote/Hook.hs

@@ -12,7 +12,7 @@ import Control.Exception.Extensible (IOException)
 import qualified Data.Map as M
 import Control.Monad.State (liftIO)
 import System.FilePath
-import System.Posix.Process
+import System.Posix.Process hiding (executeFile)
 import System.Posix.IO
 import System.IO
 import System.IO.Error (try)

RsyncFile.hs

@@ -7,7 +7,6 @@
 
 module RsyncFile where
 
-import System.Posix.Process
 import Data.String.Utils
 
 import Utility

Utility.hs

@@ -17,6 +17,7 @@ module Utility (
 	relPathDirToFile,
 	boolSystem,
 	boolSystemEnv,
+	executeFile,
 	shellEscape,
 	shellUnEscape,
 	unsetFileMode,
@@ -39,7 +40,8 @@ module Utility (
 
 import System.IO
 import System.Exit
-import System.Posix.Process
+import qualified System.Posix.Process
+import System.Posix.Process hiding (executeFile)
 import System.Posix.Signals
 import System.Posix.Files
 import System.Posix.Types
@@ -52,6 +54,7 @@ import Foreign (complement)
 import Data.List
 import Data.Maybe
 import Control.Monad (liftM2, when, unless)
+import System.Log.Logger
 
 {- A type for parameters passed to a shell command. A command can
  - be passed either some Params (multiple parameters can be included,
@@ -104,6 +107,13 @@ boolSystemEnv command params env = do
 			restoresignals oldint oldset
 			executeFile command True (toCommand params) env
 
+{- executeFile with debug logging -}
+executeFile :: FilePath -> Bool -> [String] -> Maybe [(String, String)] -> IO a
+executeFile c path p e = do
+	debugM "Utility.executeFile" $
+		"Running: " ++ c ++ " " ++ show p ++ " " ++ maybe "" show e
+	System.Posix.Process.executeFile c path p e
+
 {- Escapes a filename or other parameter to be safely able to be exposed to
  - the shell. -}
 shellEscape :: String -> String

debian/changelog

@@ -2,6 +2,7 @@ git-annex (0.20110517) UNRELEASED; urgency=low
 
   * status: New subcommand to show info about an annex, including its size.
   * --backend now overrides any backend configured in .gitattributes files.
+  * Add --debug option. Closes: #627499
 
  -- Joey Hess <joeyh@debian.org>  Mon, 16 May 2011 20:27:46 -0400
 

doc/git-annex.mdwn

@@ -330,6 +330,10 @@ Many git-annex commands will stage changes for later `git commit` by you.
 
   Enable verbose logging.
 
+* --debug
+
+  Show debug messages.
+
 * --from=repository
 
   Specifies a repository that content will be retrieved from, or that