Stable version 0.3.1

This release is dedicated to the Flycheck team,
even though ShellCheck is written entirely in Vim.

.gitignore

@@ -0,0 +1,7 @@
+*.hi
+*.o
+.tests
+jsoncheck
+shellcheck
+shellcheck.1
+dist

Makefile

@@ -2,23 +2,23 @@
 
 GHCFLAGS=-O9
 
-all: shellcheck jsoncheck .tests
+all: shellcheck .tests shellcheck.1
 	: Done
 	
 shellcheck: regardless
 	: Conditionally compiling shellcheck
 	ghc $(GHCFLAGS) --make shellcheck
 
-jsoncheck: regardless
-	: Conditionally compiling shellcheck
-	ghc $(GHCFLAGS) --make jsoncheck
-
 .tests: *.hs */*.hs
 	: Running unit tests
 	./test/runQuack && touch .tests
 
+shellcheck.1: shellcheck.1.md
+	pandoc -s -t man $< -o $@
+
 clean:
-	rm -f .tests shellcheck  *.hi *.o  ShellCheck/*.hi ShellCheck/*.o
+	rm -f .tests shellcheck shellcheck.1
+	rm -f *.hi *.o ShellCheck/*.hi ShellCheck/*.o
+	rm -rf dist
 
 regardless:
-	

README

@@ -18,9 +18,27 @@ The goals of ShellCheck are:
 ShellCheck is written in Haskell, and requires GHC, Parsec3 and Text.Regex. 
 To build the JSON interface and run the unit tests, it also requires QuickCheck2 and JSON.
 
-On Ubuntu and similar, these are called:
-  ghc6 libghc6-parsec3-dev libghc6-quickcheck2-dev libghc6-json-dev libghc-regex-compat-dev
+On Fedora, these can be installed with:
+  yum install cabal-install ghc ghc-parsec-devel ghc-QuickCheck-devel ghc-json-devel ghc-regex-compat-devel
+
+On Ubuntu and similar, use:
+  apt-get install ghc libghc-parsec3-dev libghc-json-dev libghc-regex-compat-dev libghc-quickcheck2-dev cabal-install
+
+For older releases, you may have to use:
+  apt-get install ghc6 libghc6-parsec3-dev libghc6-quickcheck2-dev libghc6-json-dev libghc-regex-compat-dev cabal-install
+
+On Mac OS X with homebrew (http://brew.sh/), use:
+  brew install cabal-install
+
+On Mac OS X with MacPorts (http://www.macports.org/), use:
+  port install hs-cabal-install
 
 Executables can be built with cabal. Tests currently still rely on a Makefile.
 
+Install:
+  cabal install
+
+  which shellcheck
+  ~/.cabal/bin/shellcheck
+
 Happy ShellChecking!

Setup.hs

@@ -0,0 +1,2 @@
+import Distribution.Simple
+main = defaultMain

ShellCheck.cabal

@@ -1,20 +1,35 @@
 Name:             ShellCheck
-Version:          0.1.0
-Description:      Shell script analysis tool
+-- Must also be updated in ShellCheck/Data.hs :
+Version:          0.3.1
+Synopsis:         Shell script analysis tool
+License:          OtherLicense
 License-file:     LICENSE
+Category:         Static Analysis
 Author:           Vidar Holen
 Maintainer:       vidar@vidarholen.net
 Homepage:         http://www.shellcheck.net/
 Build-Type:       Simple
-Cabal-Version:    >= 1.2
+Cabal-Version:    >= 1.6
+Bug-reports:      https://github.com/koalaman/shellcheck/issues
+Description:
+  The goals of ShellCheck are:
+  .
+  * To point out and clarify typical beginner's syntax issues,
+    that causes a shell to give cryptic error messages.
+  .
+  * To point out and clarify typical intermediate level semantic problems,
+    that causes a shell to behave strangely and counter-intuitively.
+  .
+  * To point out subtle caveats, corner cases and pitfalls, that may cause an
+    advanced user's otherwise working script to fail under future circumstances.
+
+source-repository head
+    type: git
+    location: git://github.com/koalaman/shellcheck.git
 
 library
-    build-depends: base >= 4, parsec, containers, regex-compat, mtl, directory
-    exposed-modules: ShellCheck.AST, ShellCheck.Parser, ShellCheck.Analytics, ShellCheck.Simple
+    build-depends: base >= 4, base < 5, parsec, containers, regex-compat, mtl, directory, json
+    exposed-modules: ShellCheck.AST, ShellCheck.Data, ShellCheck.Parser, ShellCheck.Analytics, ShellCheck.Simple
 
 executable shellcheck
     main-is: shellcheck.hs
-
-executable jsoncheck
-    build-depends: json
-    main-is: jsoncheck.hs

ShellCheck/AST.hs

@@ -23,6 +23,12 @@ import qualified Text.Regex as Re
 
 data Id = Id Int deriving (Show, Eq, Ord)
 
+data Quoted = Quoted | Unquoted deriving (Show, Eq)
+data Dashed = Dashed | Undashed deriving (Show, Eq)
+data AssignmentMode = Assign | Append deriving (Show, Eq)
+data FunctionKeyword = FunctionKeyword Bool deriving (Show, Eq)
+data FunctionParentheses = FunctionParentheses Bool deriving (Show, Eq)
+
 data Token =
     TA_Base Id String Token
     | TA_Binary Id String Token Token
@@ -42,7 +48,7 @@ data Token =
     | T_AndIf Id (Token) (Token)
     | T_Arithmetic Id Token
     | T_Array Id [Token]
-    | T_Assignment Id String Token
+    | T_Assignment Id AssignmentMode String (Maybe Token) Token
     | T_Backgrounded Id Token
     | T_Backticked Id [Token]
     | T_Bang Id
@@ -76,11 +82,11 @@ data Token =
     | T_For Id
     | T_ForArithmetic Id Token Token Token [Token]
     | T_ForIn Id String [Token] [Token]
-    | T_Function Id String Token
+    | T_Function Id FunctionKeyword FunctionParentheses String Token
     | T_GREATAND Id
     | T_Glob Id String
     | T_Greater Id
-    | T_HereDoc Id Bool Bool String
+    | T_HereDoc Id Dashed Quoted String [Token]
     | T_HereString Id Token
     | T_If Id
     | T_IfExpression Id [([Token],[Token])] [Token]
@@ -113,8 +119,10 @@ data Token =
     | T_UntilExpression Id [Token] [Token]
     | T_While Id
     | T_WhileExpression Id [Token] [Token]
+    | T_Annotation Id [Annotation] Token
     deriving (Show)
 
+data Annotation = DisableComment Integer deriving (Show, Eq)
 data ConditionType = DoubleBracket | SingleBracket deriving (Show, Eq)
 
 -- I apologize for nothing!
@@ -134,6 +142,11 @@ analyze f g i t =
         return . i $ newT
     roundAll = mapM round
 
+    roundMaybe Nothing = return Nothing
+    roundMaybe (Just v) = do
+        s <- round v
+        return (Just s)
+
     dl l v = do
         x <- roundAll l
         return $ v x
@@ -159,7 +172,10 @@ analyze f g i t =
     delve (T_IoFile id op file) = d2 op file $ T_IoFile id
     delve (T_HereString id word) = d1 word $ T_HereString id
     delve (T_FdRedirect id v t) = d1 t $ T_FdRedirect id v
-    delve (T_Assignment id v t) = d1 t $ T_Assignment id v
+    delve (T_Assignment id mode var index value) = do
+        a <- roundMaybe index
+        b <- round value
+        return $ T_Assignment id mode var a b
     delve (T_Array id t) = dl t $ T_Array id
     delve (T_Redirecting id redirs cmd) = do
         a <- roundAll redirs
@@ -204,10 +220,11 @@ analyze f g i t =
         return $ T_ForArithmetic id x y z list
 
     delve (T_Script id s l) = dl l $ T_Script id s
-    delve (T_Function id name body) = d1 body $ T_Function id name
+    delve (T_Function id a b name body) = d1 body $ T_Function id a b name
     delve (T_Condition id typ token) = d1 token $ T_Condition id typ
     delve (T_Extglob id str l) = dl l $ T_Extglob id str
     delve (T_DollarBraced id op) = d1 op $ T_DollarBraced id
+    delve (T_HereDoc id d q str l) = dl l $ T_HereDoc id d q str
 
     delve (TC_And id typ str t1 t2) = d2 t1 t2 $ TC_And id typ str
     delve (TC_Or id typ str t1 t2) = d2 t1 t2 $ TC_Or id typ str
@@ -226,6 +243,7 @@ analyze f g i t =
         return $ TA_Trinary id a b c
     delve (TA_Expansion id t) = d1 t $ TA_Expansion id
     delve (TA_Base id b t) = d1 t $ TA_Base id b
+    delve (T_Annotation id anns t) = d1 t $ T_Annotation id anns
     delve t = return t
 
 getId t = case t of
@@ -272,10 +290,10 @@ getId t = case t of
         T_DollarArithmetic id _  -> id
         T_BraceExpansion id _  -> id
         T_IoFile id _ _  -> id
-        T_HereDoc id _ _ _ -> id
+        T_HereDoc id _ _ _ _ -> id
         T_HereString id _  -> id
         T_FdRedirect id _ _  -> id
-        T_Assignment id _ _  -> id
+        T_Assignment id _ _ _ _  -> id
         T_Array id _  -> id
         T_Redirecting id _ _  -> id
         T_SimpleCommand id _ _  -> id
@@ -292,7 +310,7 @@ getId t = case t of
         T_ForIn id _ _ _  -> id
         T_SelectIn id _ _ _  -> id
         T_CaseExpression id _ _ -> id
-        T_Function id _ _  -> id
+        T_Function id _ _ _ _  -> id
         T_Arithmetic id _  -> id
         T_Script id _ _  -> id
         T_Condition id _ _  -> id
@@ -318,6 +336,7 @@ getId t = case t of
         T_DollarSingleQuoted id _ -> id
         T_DollarDoubleQuoted id _ -> id
         T_DollarBracket id _ -> id
+        T_Annotation id _ _ -> id
 
 blank :: Monad m => Token -> m ()
 blank = const $ return ()
@@ -325,3 +344,10 @@ doAnalysis f t = analyze f blank id t
 doStackAnalysis startToken endToken t = analyze startToken endToken id t
 doTransform i t = runIdentity $ analyze blank blank i t
 
+isLoop t = case t of
+        T_WhileExpression _ _ _  -> True
+        T_UntilExpression _ _ _  -> True
+        T_ForIn _ _ _ _  -> True
+        T_ForArithmetic _ _ _ _ _ -> True
+        T_SelectIn _ _ _ _  -> True
+        _ -> False

ShellCheck/Data.hs

@@ -0,0 +1,76 @@
+module ShellCheck.Data where
+
+shellcheckVersion = "0.3.1"  -- Must also be updated in ShellCheck.cabal
+
+internalVariables = [
+    -- Generic
+    "", "_", "rest", "REST",
+
+    -- Bash
+    "BASH", "BASHOPTS", "BASHPID", "BASH_ALIASES", "BASH_ARGC",
+    "BASH_ARGV", "BASH_CMDS", "BASH_COMMAND", "BASH_EXECUTION_STRING",
+    "BASH_LINENO", "BASH_REMATCH", "BASH_SOURCE", "BASH_SUBSHELL",
+    "BASH_VERSINFO", "BASH_VERSION", "COMP_CWORD", "COMP_KEY",
+    "COMP_LINE", "COMP_POINT", "COMP_TYPE", "COMP_WORDBREAKS",
+    "COMP_WORDS", "COPROC", "DIRSTACK", "EUID", "FUNCNAME", "GROUPS",
+    "HISTCMD", "HOSTNAME", "HOSTTYPE", "LINENO", "MACHTYPE", "MAPFILE",
+    "OLDPWD", "OPTARG", "OPTIND", "OSTYPE", "PIPESTATUS", "PPID", "PWD",
+    "RANDOM", "READLINE_LINE", "READLINE_POINT", "REPLY", "SECONDS",
+    "SHELLOPTS", "SHLVL", "UID", "BASH_ENV", "BASH_XTRACEFD", "CDPATH",
+    "COLUMNS", "COMPREPLY", "EMACS", "ENV", "FCEDIT", "FIGNORE",
+    "FUNCNEST", "GLOBIGNORE", "HISTCONTROL", "HISTFILE", "HISTFILESIZE",
+    "HISTIGNORE", "HISTSIZE", "HISTTIMEFORMAT", "HOME", "HOSTFILE", "IFS",
+    "IGNOREEOF", "INPUTRC", "LANG", "LC_ALL", "LC_COLLATE", "LC_CTYPE",
+    "LC_MESSAGES", "LC_NUMERIC", "LINES", "MAIL", "MAILCHECK", "MAILPATH",
+    "OPTERR", "PATH", "POSIXLY_CORRECT", "PROMPT_COMMAND",
+    "PROMPT_DIRTRIM", "PS1", "PS2", "PS3", "PS4", "SHELL", "TIMEFORMAT",
+    "TMOUT", "TMPDIR", "auto_resume", "histchars",
+
+    -- Zsh
+    "ARGV0", "BAUD", "cdpath", "COLUMNS", "CORRECT_IGNORE",
+    "DIRSTACKSIZE", "ENV", "FCEDIT", "fignore", "fpath", "histchars",
+    "HISTCHARS", "HISTFILE", "HISTSIZE", "HOME", "IFS", "KEYBOARD_HACK",
+    "KEYTIMEOUT", "LANG", "LC_ALL", "LC_COLLATE", "LC_CTYPE",
+    "LC_MESSAGES", "LC_NUMERIC", "LC_TIME", "LINES", "LISTMAX",
+    "LOGCHECK", "MAIL", "MAILCHECK", "mailpath", "manpath", "module_path",
+    "NULLCMD", "path", "POSTEDIT", "PROMPT", "PROMPT2", "PROMPT3",
+    "PROMPT4", "prompt", "PROMPT_EOL_MARK", "PS1", "PS2", "PS3", "PS4",
+    "psvar", "READNULLCMD", "REPORTTIME", "REPLY", "reply", "RPROMPT",
+    "RPS1", "RPROMPT2", "RPS2", "SAVEHIST", "SPROMPT", "STTY", "TERM",
+    "TERMINFO", "TIMEFMT", "TMOUT", "TMPPREFIX", "watch", "WATCHFMT",
+    "WORDCHARS", "ZBEEP", "ZDOTDIR", "ZLE_LINE_ABORTED",
+    "ZLE_REMOVE_SUFFIX_CHARS", "ZLE_SPACE_SUFFIX_CHARS"
+  ]
+
+variablesWithoutSpaces = [
+    "$", "-", "?", "!",
+    "BASHPID", "BASH_ARGC", "BASH_LINENO", "BASH_SUBSHELL", "EUID", "LINENO",
+    "OPTIND", "PPID", "RANDOM", "SECONDS", "SHELLOPTS", "SHLVL", "UID",
+    "COLUMNS", "HISTFILESIZE", "HISTSIZE", "LINES"
+  ]
+
+commonCommands = [
+    "admin", "alias", "ar", "asa", "at", "awk", "basename", "batch",
+    "bc", "bg", "break", "c99", "cal", "cat", "cd", "cflow", "chgrp",
+    "chmod", "chown", "cksum", "cmp", "colon", "comm", "command",
+    "compress", "continue", "cp", "crontab", "csplit", "ctags", "cut",
+    "cxref", "date", "dd", "delta", "df", "diff", "dirname", "dot",
+    "du", "echo", "ed", "env", "eval", "ex", "exec", "exit", "expand",
+    "export", "expr", "fc", "fg", "file", "find", "fold", "fort77",
+    "fuser", "gencat", "get", "getconf", "getopts", "grep", "hash",
+    "head", "iconv", "ipcrm", "ipcs", "jobs", "join", "kill", "lex",
+    "link", "ln", "locale", "localedef", "logger", "logname", "lp",
+    "ls", "m4", "mailx", "make", "man", "mesg", "mkdir", "mkfifo",
+    "more", "mv", "newgrp", "nice", "nl", "nm", "nohup", "od", "paste",
+    "patch", "pathchk", "pax", "pr", "printf", "prs", "ps", "pwd",
+    "qalter", "qdel", "qhold", "qmove", "qmsg", "qrerun", "qrls",
+    "qselect", "qsig", "qstat", "qsub", "read", "readonly", "renice",
+    "return", "rm", "rmdel", "rmdir", "sact", "sccs", "sed", "set",
+    "sh", "shift", "sleep", "sort", "split", "strings", "strip", "stty",
+    "tabs", "tail", "talk", "tee", "test", "time", "times", "touch",
+    "tput", "tr", "trap", "tsort", "tty", "type", "ulimit", "umask",
+    "unalias", "uname", "uncompress", "unexpand", "unget", "uniq",
+    "unlink", "unset", "uucp", "uudecode", "uuencode", "uustat", "uux",
+    "val", "vi", "wait", "wc", "what", "who", "write", "xargs", "yacc",
+    "zcat"
+  ]

ShellCheck/Simple.hs

@@ -15,7 +15,7 @@
     You should have received a copy of the GNU Affero General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 -}
-module ShellCheck.Simple (shellCheck, ShellCheckComment, scLine, scColumn, scSeverity, scMessage) where
+module ShellCheck.Simple (shellCheck, ShellCheckComment, scLine, scColumn, scSeverity, scCode, scMessage) where
 
 import ShellCheck.Parser
 import ShellCheck.Analytics
@@ -23,21 +23,38 @@ import Data.Maybe
 import Text.Parsec.Pos
 import Data.List
 
-shellCheck :: String -> [ShellCheckComment]
-shellCheck script =
+
+prop_findsParseIssue =
+    let comments = shellCheck "echo \"$12\"" [] in
+        (length comments) == 1 && (scCode $ head comments) == 1037
+prop_commentDisablesParseIssue1 =
+    null $ shellCheck "#shellcheck disable=SC1037\necho \"$12\"" []
+prop_commentDisablesParseIssue2 =
+    null $ shellCheck "#shellcheck disable=SC1037\n#lol\necho \"$12\"" []
+
+prop_findsAnalysisIssue =
+    let comments = shellCheck "echo $1" [] in
+        (length comments) == 1 && (scCode $ head comments) == 2086
+prop_commentDisablesAnalysisIssue1 =
+    null $ shellCheck "#shellcheck disable=SC2086\necho $1" []
+prop_commentDisablesAnalysisIssue2 =
+    null $ shellCheck "#shellcheck disable=SC2086\n#lol\necho $1" []
+
+shellCheck :: String -> [AnalysisOption] -> [ShellCheckComment]
+shellCheck script options =
     let (ParseResult result notes) = parseShell "-" script in
         let allNotes = notes ++ (concat $ maybeToList $ do
-            (tree, map) <- result
-            let newMap = runAllAnalytics tree map
-            return $ notesFromMap newMap
+            (tree, posMap) <- result
+            let list = runAnalytics options tree
+            return $ map (noteToParseNote posMap) $ filterByAnnotation tree list
             )
         in
             map formatNote $ nub $ sortNotes allNotes
 
-data ShellCheckComment = ShellCheckComment { scLine :: Int, scColumn :: Int, scSeverity :: String, scMessage :: String }
+data ShellCheckComment = ShellCheckComment { scLine :: Int, scColumn :: Int, scSeverity :: String, scCode :: Int, scMessage :: String }
 
 instance Show ShellCheckComment where
-    show c = concat ["(", show $ scLine c, ",", show $ scColumn c, ") ", scSeverity c, ": ", scMessage c]
+    show c = concat ["(", show $ scLine c, ",", show $ scColumn c, ") ", scSeverity c, ": ", show (scCode c), " ", scMessage c]
 
 severityToString s =
     case s of
@@ -46,4 +63,5 @@ severityToString s =
         InfoC -> "info"
         StyleC -> "style"
 
-formatNote (ParseNote pos severity text) = ShellCheckComment (sourceLine pos) (sourceColumn pos) (severityToString severity) text
+formatNote (ParseNote pos severity code text) =
+    ShellCheckComment (sourceLine pos) (sourceColumn pos) (severityToString severity) (fromIntegral code) text

jsoncheck.hs

@@ -1,32 +0,0 @@
-{-
-    This file is part of ShellCheck.
-    http://www.vidarholen.net/contents/shellcheck
-
-    ShellCheck is free software: you can redistribute it and/or modify
-    it under the terms of the GNU Affero General Public License as published by
-    the Free Software Foundation, either version 3 of the License, or
-    (at your option) any later version.
-
-    ShellCheck is distributed in the hope that it will be useful,
-    but WITHOUT ANY WARRANTY; without even the implied warranty of
-    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-    GNU Affero General Public License for more details.
-
-    You should have received a copy of the GNU Affero General Public License
-    along with this program.  If not, see <http://www.gnu.org/licenses/>.
--}
-import ShellCheck.Simple
-import Text.JSON
-
-instance JSON ShellCheckComment where
-  showJSON c = makeObj [
-      ("line", showJSON $ scLine c), 
-      ("column", showJSON $ scColumn c),
-      ("level", showJSON $ scSeverity c),
-      ("message", showJSON $ scMessage c)
-      ]
-  readJSON = undefined
-
-main = do
-  script <- getContents
-  putStrLn $ encodeStrict $ shellCheck script 

shellcheck.1.md

@@ -0,0 +1,121 @@
+% SHELLCHECK(1) Shell script analysis tool
+
+# NAME
+
+shellcheck - Shell script analysis tool
+
+# SYNOPSIS
+
+**shellcheck** [*OPTIONS*...] *FILES*...
+
+# DESCRIPTION
+
+ShellCheck is a static analysis and linting tool for sh/bash scripts. It's
+mainly focused on handling typical beginner and intermediate level syntax
+errors and pitfalls where the shell just gives a cryptic error message or
+strange behavior, but it also reports on a few more advanced issues where
+corner cases can cause delayed failures.
+
+# OPTIONS
+
+**-f** *FORMAT*, **--format=***FORMAT*
+
+:   Specify the output format of shellcheck, which prints its results in the
+    standard output. Subsequent **-f** options are ignored, see **FORMATS**
+    below for more information.
+
+**-e**\ *CODE1*[,*CODE2*...],\ **--exclude=***CODE1*[,*CODE2*...]
+
+:   Explicitly exclude the specified codes from the report. Subsequent **-e**
+    options are cumulative, but all the codes can be specified at once,
+    comma-separated as a single argument.
+
+**-s**\ *shell*,\ **--shell=***shell*
+
+:   Specify Bourne shell dialect. Valid values are *sh*, *bash*, *ksh* and
+    *zsh*. The default is to use the file's shebang, or *bash* if the target
+    shell can't be determined.
+
+# FORMATS
+
+**tty**
+
+:   Plain text, human readable output. This is the default.
+
+**gcc**
+
+:   GCC compatible output. Useful for editors that support compiling and
+    showing syntax errors.
+
+    For example, in Vim, `:set makeprg=shellcheck\ -f\ gcc\ %` will allow
+    using `:make` to check the script, and `:cnext` to jump to the next error.
+
+        <file>:<line>:<column>: <type>: <message>
+
+**checkstyle**
+
+:   Checkstyle compatible XML output. Supported directly or through plugins
+    by many IDEs and build monitoring systems.
+
+        <?xml version='1.0' encoding='UTF-8'?>
+        <checkstyle version='4.3'>
+          <file name='file'>
+            <error
+              line='line'
+              column='column'
+              severity='severity'
+              message='message'
+              source='ShellCheck.SC####' />
+            ...
+          </file>
+          ...
+        </checkstyle>
+
+**json**
+
+:   Json is a popular serialization format that is more suitable for web
+    applications. ShellCheck's json is compact and contains only the bare
+    minimum.
+
+        [
+          {
+            "line": line,
+            "column": column,
+            "level": level,
+            "code": ####,
+            "message": message
+          },
+          ...
+        ]
+
+# DIRECTIVES
+ShellCheck directives can be specified as comments in the shell script
+before a command or block:
+
+    # shellcheck key=value key=value
+    command-or-structure
+
+For example, to suppress SC2035 about using `./*.jpg`:
+
+    # shellcheck disable=SC2035
+    echo "Files: " *.jpg
+
+Valid keys are:
+
+**disable**
+:   Disables a comma separated list of error codes for the following command.
+    The command can be a simple command like `echo foo`, or a compound command
+    like a function definition, subshell block or loop.
+
+
+# AUTHOR
+ShellCheck is written and maintained by Vidar Holen.
+
+# REPORTING BUGS
+Bugs and issues can be reported on GitHub:
+
+https://github.com/koalaman/shellcheck/issues
+
+# SEE ALSO
+
+sh(1) bash(1)

shellcheck.hs

@@ -15,16 +15,74 @@
     You should have received a copy of the GNU Affero General Public License
     along with this program.  If not, see <http://www.gnu.org/licenses/>.
 -}
+import Control.Exception
 import Control.Monad
+import Data.Char
+import Data.Maybe
 import GHC.Exts
 import GHC.IO.Device
+import Prelude hiding (catch)
+import ShellCheck.Data
 import ShellCheck.Simple
+import ShellCheck.Analytics
+import System.Console.GetOpt
 import System.Directory
 import System.Environment
 import System.Exit
 import System.IO
+import Text.JSON
+import qualified Data.Map as Map
 
+data Flag = Flag String String
 
+header = "Usage: shellcheck [OPTIONS...] FILES..."
+options = [
+    Option ['f'] ["format"]
+        (ReqArg (Flag "format") "FORMAT") "output format",
+    Option ['e'] ["exclude"]
+        (ReqArg (Flag "exclude") "CODE1,CODE2..") "exclude types of warnings",
+    Option ['s'] ["shell"]
+        (ReqArg (Flag "shell") "SHELLNAME") "Specify dialect (bash,sh,ksh,zsh)",
+    Option ['V'] ["version"]
+        (NoArg $ Flag "version" "true") "Print version information"
+    ]
+
+printErr = hPutStrLn stderr
+
+syntaxFailure = ExitFailure 3
+supportFailure = ExitFailure 4
+
+instance JSON ShellCheckComment where
+  showJSON c = makeObj [
+      ("line", showJSON $ scLine c),
+      ("column", showJSON $ scColumn c),
+      ("level", showJSON $ scSeverity c),
+      ("code", showJSON $ scCode c),
+      ("message", showJSON $ scMessage c)
+      ]
+  readJSON = undefined
+
+parseArguments argv =
+    case getOpt Permute options argv of
+        (opts, files, []) -> do
+            verifyOptions opts files
+            return $ Just (opts, files)
+
+        (_, _, errors) -> do
+            printErr $ (concat errors) ++ "\n" ++ usageInfo header options
+            exitWith syntaxFailure
+
+formats = Map.fromList [
+    ("json", forJson),
+    ("gcc", forGcc),
+    ("checkstyle", forCheckstyle),
+    ("tty", forTty)
+    ]
+
+forTty options files = do
+    output <- mapM doFile files
+    return $ and output
+  where
     clear = ansi 0
     ansi n = "\x1B[" ++ (show n) ++ "m"
 
@@ -38,21 +96,16 @@ colorForLevel _ = 0 -- none
 
     colorComment level comment = (ansi $ colorForLevel level) ++ comment ++ clear
 
-doFile path colorFunc = do
-    let actualPath = if path == "-" then "/dev/stdin" else path
-    exists <- doesFileExist actualPath
-    if exists then do
-        contents <- readFile actualPath
-        doInput path contents colorFunc
-      else do
-        putStrLn (colorFunc "error" $ "No such file: " ++ actualPath)
+    doFile path = do
+        contents <- readContents path
+        doInput path contents
 
-doInput filename contents colorFunc = do
+    doInput filename contents = do
         let fileLines = lines contents
         let lineCount = length fileLines
-    let comments = shellCheck contents
+        let comments = getComments options contents
         let groups = groupWith scLine comments
-    if not $ null comments then do
+        colorFunc <- getColorFunc
         mapM_ (\x -> do
             let lineNum = scLine (head x)
             let line = if lineNum < 1 || lineNum > lineCount
@@ -64,23 +117,184 @@ doInput filename contents colorFunc = do
             mapM (\c -> putStrLn (colorFunc (scSeverity c) $ cuteIndent c)) x
             putStrLn ""
           ) groups
-      else do
-        putStrLn ("No comments for " ++ filename)
+        return $ null comments
 
     cuteIndent comment =
-    (replicate ((scColumn comment) - 1) ' ') ++ "^-- " ++ (scMessage comment)
+        (replicate ((scColumn comment) - 1) ' ') ++ "^-- " ++ (code $ scCode comment) ++ ": " ++ (scMessage comment)
+
+    code code = "SC" ++ (show code)
 
     getColorFunc = do
         term <- hIsTerminalDevice stdout
         return $ if term then colorComment else const id
 
+-- This totally ignores the filenames. Fixme?
+forJson options files = do
+    comments <- liftM concat $ mapM (commentsFor options) files
+    putStrLn $ encodeStrict $ comments
+    return . null $ comments
+
+-- Mimic GCC "file:line:col: (error|warning|note): message" format
+forGcc options files = do
+    files <- mapM process files
+    return $ and files
+  where
+    process file = do
+        contents <- readContents file
+        let comments = makeNonVirtual (getComments options contents) contents
+        mapM_ (putStrLn . format file) comments
+        return $ null comments
+
+    format filename c = concat [
+            filename, ":",
+            show $ scLine c, ":",
+            show $ scColumn c, ": ",
+            case scSeverity c of
+                "error" -> "error"
+                "warning" -> "warning"
+                _ -> "note",
+            ": ",
+            concat . lines $ scMessage c,
+            " [SC", show $ scCode c, "]"
+      ]
+
+-- Checkstyle compatible output. A bit of a hack to avoid XML dependencies
+forCheckstyle options files = do
+    putStrLn "<?xml version='1.0' encoding='UTF-8'?>"
+    putStrLn "<checkstyle version='4.3'>"
+    statuses <- mapM (\x -> process x `catch` report) files
+    putStrLn "</checkstyle>"
+    return $ and statuses
+  where
+    process file = do
+        comments <- commentsFor options file
+        putStrLn (formatFile file comments)
+        return $ null comments
+    report error = do
+        printErr $ show (error :: SomeException)
+        return False
+
+    severity "error" = "error"
+    severity "warning" = "warning"
+    severity _ = "info"
+    attr s v = concat [ s, "='", escape v, "' " ]
+    escape msg = concatMap escape' msg
+    escape' c = if isOk c then [c] else "&#" ++ (show $ ord c) ++ ";"
+    isOk x = any ($x) [isAsciiUpper, isAsciiLower, isDigit, (`elem` " ./")]
+
+    formatFile name comments = concat [
+        "<file ", attr "name" name, ">\n",
+            concatMap format comments,
+        "</file>"
+        ]
+
+    format c = concat [
+        "<error ",
+        attr "line" $ show . scLine $ c,
+        attr "column" $ show . scColumn $ c,
+        attr "severity" $ severity . scSeverity $ c,
+        attr "message" $ scMessage c,
+        attr "source" $ "ShellCheck.SC" ++ (show $ scCode c),
+        "/>\n"
+        ]
+
+commentsFor options file =
+    liftM (getComments options) $ readContents file
+
+getComments options contents =
+    excludeCodes (getExclusions options) $ shellCheck contents analysisOptions
+  where
+    analysisOptions = catMaybes [ shellOption ]
+    shellOption = do
+        option <- getOption options "shell"
+        sh <- shellForExecutable option
+        return $ ForceShell sh
+
+
+readContents file = if file == "-" then getContents else readFile file
+
+-- Realign comments from a tabstop of 8 to 1
+makeNonVirtual comments contents =
+    map fix comments
+  where
+    ls = lines contents
+    fix c = c { scColumn = real (ls !! (scLine c - 1)) 0 0 (scColumn c) }
+    real _ r v target | target <= v = r
+    real [] r v _ = r -- should never happen
+    real ('\t':rest) r v target =
+        real rest (r+1) (v + 8 - (v `mod` 8)) target
+    real (_:rest) r v target = real rest (r+1) (v+1) target
+
+getOption [] _ = Nothing
+getOption ((Flag var val):_) name | name == var = return val
+getOption (_:rest) flag = getOption rest flag
+
+getOptions options name =
+    map (\(Flag _ val) -> val) . filter (\(Flag var _) -> var == name) $ options
+
+split char str =
+    split' str []
+  where
+    split' (a:rest) element =
+        if a == char
+        then (reverse element) : split' rest []
+        else split' rest (a:element)
+    split' [] element = [reverse element]
+
+getExclusions options =
+    let elements = concatMap (split ',') $ getOptions options "exclude"
+        clean = dropWhile (not . isDigit)
+    in
+        map (Prelude.read . clean) elements :: [Int]
+
+excludeCodes codes comments =
+    filter (not . hasCode) comments
+  where
+    hasCode c = scCode c `elem` codes
+
 main = do
     args <- getArgs
-    colors <- getColorFunc
-    if null args then do
-        hPutStrLn stderr "shellcheck -- bash/sh script static analysis tool"
-        hPutStrLn stderr "Usage: shellcheck filenames..."
-        exitFailure
-      else
-        mapM (\f -> doFile f colors) args
+    parsedArgs <- parseArguments args
+    code <- do
+        status <- process parsedArgs
+        return $ if status then ExitSuccess else ExitFailure 1
+     `catch` return
+     `catch` \err -> do
+        printErr $ show (err :: SomeException)
+        return $ ExitFailure 2
+    exitWith code
 
+process Nothing = return False
+process (Just (options, files)) = do
+  let format = fromMaybe "tty" $ getOption options "format" in
+    case Map.lookup format formats of
+        Nothing -> do
+            printErr $ "Unknown format " ++ format
+            printErr $ "Supported formats:"
+            mapM_ (printErr . write) $ Map.keys formats
+            exitWith supportFailure
+          where write s = "  " ++ s
+        Just f -> do
+            f options files
+
+verifyOptions opts files = do
+    when (isJust $ getOption opts "version") printVersionAndExit
+
+    let shell = getOption opts "shell" in
+        if isNothing shell
+        then return ()
+        else when (isNothing $ shell >>= shellForExecutable) $ do
+                printErr $ "Unknown shell: " ++ (fromJust shell)
+                exitWith supportFailure
+
+    when (null files) $ do
+        printErr "No files specified.\n"
+        printErr $ usageInfo header options
+        exitWith syntaxFailure
+
+printVersionAndExit = do
+    putStrLn $ "ShellCheck - shell script analysis tool"
+    putStrLn $ "version: " ++ shellcheckVersion
+    putStrLn $ "license: GNU Affero General Public License, version 3"
+    putStrLn $ "website: http://www.shellcheck.net"
+    exitWith ExitSuccess