Merge pull request joewalnes#56 from asergeyev/pathchecks

Changing how websocketd works with arguments that point it to directories.
rjnagal · Mar 30, 2014 · 596ca45 · 596ca45
2 parents c091e95 + a67a4b8
commit 596ca45
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Showing 4 changed files with 132 additions and 53 deletions.
diff --git a/config.go b/config.go
@@ -9,6 +9,7 @@ import (
 	"flag"
 	"fmt"
 	"os"
+	"os/exec"
 	"path/filepath"
 	"runtime"
 	"strings"
@@ -49,10 +50,13 @@ var defaultPassEnv = map[string]string{
 	"windows": "SystemRoot,COMSPEC,PATHEXT,WINDIR",
 }
 
-func parseCommandLine() Config {
+func parseCommandLine() *Config {
 	var mainConfig Config
 	var config libwebsocketd.Config
 
+	flag.Usage = func() {}
+	flag.CommandLine = flag.NewFlagSet(os.Args[0], flag.ContinueOnError)
+
 	// If adding new command line options, also update the help text in help.go.
 	// The flag library's auto-generate help message isn't pretty enough.
 
@@ -78,7 +82,15 @@ func parseCommandLine() Config {
 	devConsoleFlag := flag.Bool("devconsole", false, "Enable development console (cannot be used in conjunction with --staticdir)")
 	passEnvFlag := flag.String("passenv", defaultPassEnv[runtime.GOOS], "List of envvars to pass to subprocesses (others will be cleaned out)")
 
-	flag.Parse()
+	err := flag.CommandLine.Parse(os.Args[1:])
+	if err != nil {
+		if err == flag.ErrHelp {
+			PrintHelp()
+		} else {
+			ShortHelp()
+		}
+		os.Exit(2)
+	}
 
 	port := *portFlag
 	if port == 0 {
@@ -99,28 +111,10 @@ func parseCommandLine() Config {
 	}
 	mainConfig.MaxForks = *maxForksFlag
 	mainConfig.BasePath = *basePathFlag
-
-	switch *logLevelFlag {
-	case "debug":
-		mainConfig.LogLevel = libwebsocketd.LogDebug
-		break
-	case "trace":
-		mainConfig.LogLevel = libwebsocketd.LogTrace
-		break
-	case "access":
-		mainConfig.LogLevel = libwebsocketd.LogAccess
-		break
-	case "info":
-		mainConfig.LogLevel = libwebsocketd.LogInfo
-		break
-	case "error":
-		mainConfig.LogLevel = libwebsocketd.LogError
-		break
-	case "fatal":
-		mainConfig.LogLevel = libwebsocketd.LogFatal
-		break
-	default:
-		PrintHelp()
+	mainConfig.LogLevel = libwebsocketd.LevelFromString(*logLevelFlag)
+	if mainConfig.LogLevel == libwebsocketd.LogUnknown {
+		fmt.Printf("Incorrect loglevel flag '%s'. Use --help to see allowed values.\n", *logLevelFlag)
+		ShortHelp()
 		os.Exit(1)
 	}
 
@@ -134,17 +128,18 @@ func parseCommandLine() Config {
 	config.ServerSoftware = fmt.Sprintf("websocketd/%s", Version())
 
 	if len(os.Args) == 1 {
-		PrintHelp()
+		fmt.Printf("Command line arguments are missing.\n")
+		ShortHelp()
 		os.Exit(1)
 	}
 
 	if *versionFlag {
-		fmt.Printf("%s %s\n", filepath.Base(os.Args[0]), Version())
+		fmt.Printf("%s %s\n", HelpProcessName(), Version())
 		os.Exit(2)
 	}
 
 	if *licenseFlag {
-		fmt.Printf("%s %s\n", filepath.Base(os.Args[0]), Version())
+		fmt.Printf("%s %s\n", HelpProcessName(), Version())
 		fmt.Printf("%s\n", libwebsocketd.License)
 		os.Exit(2)
 	}
@@ -184,30 +179,67 @@ func parseCommandLine() Config {
 	args := flag.Args()
 	if len(args) < 1 && config.ScriptDir == "" && config.StaticDir == "" && config.CgiDir == "" {
 		fmt.Fprintf(os.Stderr, "Please specify COMMAND or provide --dir, --staticdir or --cgidir argument.\n")
+		ShortHelp()
 		os.Exit(1)
 	}
 
 	if len(args) > 0 {
 		if config.ScriptDir != "" {
 			fmt.Fprintf(os.Stderr, "Ambiguous. Provided COMMAND and --dir argument. Please only specify just one.\n")
+			ShortHelp()
+			os.Exit(1)
+		}
+		if path, err := exec.LookPath(args[0]); err == nil {
+			config.CommandName = path // This can be command in PATH that we are able to execute
+			config.CommandArgs = flag.Args()[1:]
+			config.UsingScriptDir = false
+		} else {
+			fmt.Fprintf(os.Stderr, "Unable to locate specified COMMAND '%s' in OS path.\n", args[0])
+			ShortHelp()
 			os.Exit(1)
 		}
-		config.CommandName = args[0]
-		config.CommandArgs = flag.Args()[1:]
-		config.UsingScriptDir = false
 	}
 
-	if len(config.ScriptDir) > 0 {
+	if config.ScriptDir != "" {
 		scriptDir, err := filepath.Abs(config.ScriptDir)
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "Could not resolve absolute path to dir '%s'.\n", config.ScriptDir)
+			ShortHelp()
+			os.Exit(1)
+		}
+		inf, err := os.Stat(scriptDir)
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "Could not find your script dir '%s'.\n", config.ScriptDir)
+			ShortHelp()
+			os.Exit(1)
+		}
+		if !inf.IsDir() {
+			fmt.Fprintf(os.Stderr, "Did you mean to specify COMMAND instead of --dir '%s'?\n", config.ScriptDir)
+			ShortHelp()
+			os.Exit(1)
+		} else {
+			config.ScriptDir = scriptDir
+			config.UsingScriptDir = true
+		}
+	}
+
+	if config.CgiDir != "" {
+		if inf, err := os.Stat(config.CgiDir); err != nil || !inf.IsDir() {
+			fmt.Fprintf(os.Stderr, "Your CGI dir '%s' is not pointing to an accessible directory.\n", config.CgiDir)
+			ShortHelp()
+			os.Exit(1)
+		}
+	}
+
+	if config.StaticDir != "" {
+		if inf, err := os.Stat(config.StaticDir); err != nil || !inf.IsDir() {
+			fmt.Fprintf(os.Stderr, "Your static dir '%s' is not pointing to an accessible directory.\n", config.StaticDir)
+			ShortHelp()
 			os.Exit(1)
 		}
-		config.ScriptDir = scriptDir
-		config.UsingScriptDir = true
 	}
 
 	mainConfig.Config = &config
 
-	return mainConfig
+	return &mainConfig
 }
diff --git a/help.go b/help.go
@@ -23,11 +23,9 @@ a WebSocket server.
 Usage:
 
   Export a single executable program a WebSocket server:
-
-    {{binary}} [options] program [program args]
+    {{binary}} [options] COMMAND [command args]
 
   Or, export an entire directory of executables as WebSocket endpoints:
-
     {{binary}} [options] --dir=SOMEDIR
 
 Options:
@@ -38,12 +36,12 @@ Options:
                                  Use square brackets to specify IPv6 address. 
                                  Default: "" (all)
 
-  --ssl                          Listen for HTTPS socket instead of regular HTTP.                     
-  --sslcert=FILE                 All three options must be used together or all of
+  --ssl                          Listen for HTTPS socket instead of HTTP.                     
+  --sslcert=FILE                 All three options must be used or all of
   --sslkey=FILE                  them should be omitted. 
 
-  --passenv VAR[,VAR...]         Lists environment variables allowed to be passed
-                                 to executed scripts.
+  --passenv VAR[,VAR...]         Lists environment variables allowed to be
+                                 passed to executed scripts.
 
   --basepath=PATH                Base path in URLs to serve from. 
                                  Default: / (root of domain)
@@ -76,23 +74,50 @@ Options:
                                  This flag cannot be used in conjunction
                                  with --staticdir or --cgidir.
 
-  --loglevel={debug,             Log level to use (from most to least
-              trace,             verbose).
-              access,            Default: access
-              info,
-              error,
-              fatal}
+  --loglevel=LEVEL               Log level to use (default access).
+                                 From most to least verbose:
+                                 debug, trace, access, info, error, fatal
 
 Full documentation at http://websocketd.com/
 
 Copyright 2013 Joe Walnes and the websocketd team. All rights reserved.
 BSD license: Run '{{binary}} --license' for details.
+`
+	short = `
+Usage:
+
+  Export a single executable program a WebSocket server:
+    {{binary}} [options] COMMAND [command args]
+
+  Or, export an entire directory of executables as WebSocket endpoints:
+    {{binary}} [options] --dir=SOMEDIR
+
+  Or, show extended help message using:
+    {{binary}} --help
 `
 )
 
+func get_help_message(content string) string {
+	msg := strings.Trim(content, " \n")
+	msg = strings.Replace(msg, "{{binary}}", HelpProcessName(), -1)
+	return strings.Replace(msg, "{{version}}", Version(), -1)
+}
+
+func HelpProcessName() string {
+	binary := os.Args[0]
+	if strings.Contains(binary, "/go-build") { // this was run using "go run", let's use something appropriate
+		binary = "websocketd"
+	} else {
+		binary = filepath.Base(binary)
+	}
+	return binary
+}
+
 func PrintHelp() {
-	msg := strings.Trim(help, " \n")
-	msg = strings.Replace(msg, "{{binary}}", filepath.Base(os.Args[0]), -1)
-	msg = strings.Replace(msg, "{{version}}", Version(), -1)
-	fmt.Fprintf(os.Stderr, "%s\n", msg)
+	fmt.Fprintf(os.Stderr, "%s\n", get_help_message(help))
+}
+
+func ShortHelp() {
+	// Shown after some error
+	fmt.Fprintf(os.Stderr, "\n%s\n", get_help_message(short))
 }
diff --git a/libwebsocketd/logscope.go b/libwebsocketd/logscope.go
@@ -19,6 +19,9 @@ const (
 	LogInfo
 	LogError
 	LogFatal
+
+	LogNone    = 126
+	LogUnknown = 127
 )
 
 type LogFunc func(logScope *LogScope, level LogLevel, levelName string, category string, msg string, args ...interface{})
@@ -85,3 +88,24 @@ func RootLogScope(minLevel LogLevel, logFunc LogFunc) *LogScope {
 func Timestamp() string {
 	return time.Now().Format(time.RFC1123Z)
 }
+
+func LevelFromString(s string) LogLevel {
+	switch s {
+	case "debug":
+		return LogDebug
+	case "trace":
+		return LogTrace
+	case "access":
+		return LogAccess
+	case "info":
+		return LogInfo
+	case "error":
+		return LogError
+	case "fatal":
+		return LogFatal
+	case "none":
+		return LogNone
+	default:
+		return LogUnknown
+	}
+}
diff --git a/main.go b/main.go
@@ -6,7 +6,6 @@
 package main
 
 import (
-	"flag"
 	"fmt"
 	"net/http"
 	"os"
@@ -35,7 +34,6 @@ func log(l *libwebsocketd.LogScope, level libwebsocketd.LogLevel, levelName stri
 }
 
 func main() {
-	flag.Usage = PrintHelp
 	config := parseCommandLine()
 
 	log := libwebsocketd.RootLogScope(config.LogLevel, log)