Added run() and exec() functions

eval/eval_api.go

@@ -8,6 +8,7 @@ import (
 	"time"
 
 	"fortio.org/log"
+	"fortio.org/terminal"
 	"grol.io/grol/ast"
 	"grol.io/grol/lexer"
 	"grol.io/grol/object"
@@ -28,6 +29,7 @@ const (
 )
 
 type State struct {
+	Term       *terminal.Terminal
 	Out        io.Writer
 	LogOut     io.Writer
 	macroState *object.Environment

eval/stack.go

@@ -55,6 +55,12 @@ func (s *State) Errorf(format string, args ...interface{}) object.Error {
 	return s.NewError(fmt.Sprintf(format, args...))
 }
 
+// Errorfp formats and create an *object.Error using given format and args.
+func (s *State) Errorfp(format string, args ...interface{}) *object.Error {
+	e := s.Errorf(format, args...)
+	return &e
+}
+
 // Error converts from a go error to an object.Error.
 // If the error is nil, it returns object.NULL instead (no error).
 func (s *State) Error(err error) object.Object {

extensions/extension.go

@@ -201,6 +201,9 @@ func initInternal(c *Config) error {
 	createMisc()
 	createTimeFunctions()
 	createImageFunctions()
+	if c.UnrestrictedIOs {
+		createShellFunctions()
+	}
 	return nil
 }
 

extensions/shell.go

@@ -0,0 +1,87 @@
+package extensions
+
+import (
+	"bytes"
+	"context"
+	"os"
+	"os/exec"
+
+	"fortio.org/log"
+	"grol.io/grol/eval"
+	"grol.io/grol/object"
+)
+
+func createCmd(s eval.State, args []object.Object) (*exec.Cmd, *object.Error) {
+	cmdArgs := make([]string, 0, len(args))
+	for _, arg := range args {
+		if arg.Type() != object.STRING {
+			return nil, s.Errorfp("exec: argument %s not a string", arg.Inspect())
+		}
+		cmdArgs = append(cmdArgs, arg.(object.String).Value)
+	}
+	//nolint:gosec // we do want to run the command given by the user.
+	return exec.CommandContext(s.Context, cmdArgs[0], cmdArgs[1:]...), nil
+}
+
+var (
+	stdout = object.String{Value: "stdout"}
+	stderr = object.String{Value: "stderr"}
+)
+
+func createShellFunctions() {
+	shellFn := object.Extension{
+		Name:     "exec",
+		MinArgs:  1,
+		MaxArgs:  -1,
+		Help:     "executes a command and returns its stdout, stderr and any error",
+		ArgTypes: []object.Type{object.STRING},
+		Callback: func(env any, _ string, args []object.Object) object.Object {
+			s := env.(*eval.State)
+			cmd, oerr := createCmd(*s, args)
+			if oerr != nil {
+				return *oerr
+			}
+			log.Infof("Running %#v", cmd)
+			var sout, serr bytes.Buffer
+			cmd.Stdout = &sout
+			cmd.Stderr = &serr
+			err := cmd.Run()
+			res := object.MakeQuad(stdout, object.String{Value: sout.String()},
+				stderr, object.String{Value: serr.String()})
+			if err != nil {
+				res = res.Set(eval.ErrorKey, object.String{Value: err.Error()})
+			} else {
+				res = res.Set(eval.ErrorKey, object.NULL)
+			}
+			return res
+		},
+		DontCache: true,
+	}
+	MustCreate(shellFn)
+	shellFn.Name = "run"
+	shellFn.Help = "runs a command"
+	shellFn.Callback = func(env any, _ string, args []object.Object) object.Object {
+		s := env.(*eval.State)
+		if s.Term != nil {
+			s.Term.Suspend()
+		}
+		s.Context, s.Cancel = context.WithCancel(context.Background()) // no timeout.
+		cmd, oerr := createCmd(*s, args)
+		if oerr != nil {
+			return *oerr
+		}
+		log.Infof("Running %#v", cmd)
+		cmd.Stdin = os.Stdin
+		cmd.Stdout = os.Stdout
+		cmd.Stderr = os.Stderr
+		err := cmd.Run()
+		if s.Term != nil {
+			s.Context, s.Cancel = s.Term.Resume(context.Background())
+		}
+		if err != nil {
+			return s.Error(err)
+		}
+		return object.NULL
+	}
+	MustCreate(shellFn)
+}

go.mod

@@ -8,7 +8,7 @@ require (
 	fortio.org/safecast v0.1.1
 	fortio.org/sets v1.2.0
 	fortio.org/struct2env v0.4.1
-	fortio.org/terminal v0.8.2
+	fortio.org/terminal v0.8.3-0.20240917004350-924e9d04943f
 	fortio.org/testscript v0.3.2 // only for tests
 	fortio.org/version v1.0.4
 	github.com/rivo/uniseg v0.4.7
@@ -18,7 +18,7 @@ require (
 require (
 	fortio.org/term v0.23.0-fortio-6 // indirect
 	github.com/kortschak/goroutine v1.1.2 // indirect
-	golang.org/x/crypto/x509roots/fallback v0.0.0-20240910204333-9e92970a1eb4 // indirect
+	golang.org/x/crypto/x509roots/fallback v0.0.0-20240916204253-42ee18b96377 // indirect
 	golang.org/x/exp v0.0.0-20240909161429-701f63a606c0 // indirect
 	golang.org/x/sys v0.25.0 // indirect
 	golang.org/x/tools v0.25.0 // indirect

go.sum

@@ -12,8 +12,8 @@ fortio.org/struct2env v0.4.1 h1:rJludAMO5eBvpWplWEQNqoVDFZr4RWMQX7RUapgZyc0=
 fortio.org/struct2env v0.4.1/go.mod h1:lENUe70UwA1zDUCX+8AsO663QCFqYaprk5lnPhjD410=
 fortio.org/term v0.23.0-fortio-6 h1:pKrUX0tKOxyEhkhLV50oJYucTVx94rzFrXc24lIuLvk=
 fortio.org/term v0.23.0-fortio-6/go.mod h1:7buBfn81wEJUGWiVjFNiUE/vxWs5FdM9c7PyZpZRS30=
-fortio.org/terminal v0.8.2 h1:kluLHjxsuflyRpkp9HzVM5Df8mbiX1tdDRN9Jdlp2M4=
-fortio.org/terminal v0.8.2/go.mod h1:4mFl6U7FmnQ+D/NZuxq05QDX/guBTwCRb2+DxTOj4Tg=
+fortio.org/terminal v0.8.3-0.20240917004350-924e9d04943f h1:HDn1oOJCrWswgHqFMK4Mxch2/ypWeCOuqta8NKQAS2Q=
+fortio.org/terminal v0.8.3-0.20240917004350-924e9d04943f/go.mod h1:WtVOOMZCaQY2lOV6EIIX3+QKRCwr+jX4OeROc6fN2qc=
 fortio.org/testscript v0.3.2 h1:ks5V+Y6H6nmeGqnVlZuLdiFwpqXemDkEnyGgCZa/ZNA=
 fortio.org/testscript v0.3.2/go.mod h1:Z2kUvEDHYETV8FLxsdA6zwSZ8sZUiTNJh2Dw5c4a3Pg=
 fortio.org/version v1.0.4 h1:FWUMpJ+hVTNc4RhvvOJzb0xesrlRmG/a+D6bjbQ4+5U=
@@ -22,8 +22,8 @@ github.com/kortschak/goroutine v1.1.2 h1:lhllcCuERxMIK5cYr8yohZZScL1na+JM5JYPRcl
 github.com/kortschak/goroutine v1.1.2/go.mod h1:zKpXs1FWN/6mXasDQzfl7g0LrGFIOiA6cLs9eXKyaMY=
 github.com/rivo/uniseg v0.4.7 h1:WUdvkW8uEhrYfLC4ZzdpI2ztxP1I582+49Oc5Mq64VQ=
 github.com/rivo/uniseg v0.4.7/go.mod h1:FN3SvrM+Zdj16jyLfmOkMNblXMcoc8DfTHruCPUcx88=
-golang.org/x/crypto/x509roots/fallback v0.0.0-20240910204333-9e92970a1eb4 h1:2ET4PwUR2nlFyH11/NrFz+OHyYCrnI1Gz5diQ3ZRi8A=
-golang.org/x/crypto/x509roots/fallback v0.0.0-20240910204333-9e92970a1eb4/go.mod h1:kNa9WdvYnzFwC79zRpLRMJbdEFlhyM5RPFBBZp/wWH8=
+golang.org/x/crypto/x509roots/fallback v0.0.0-20240916204253-42ee18b96377 h1:aDWu69N3Si4isYMY1ppnuoGEFypX/E5l4MWA//GPClw=
+golang.org/x/crypto/x509roots/fallback v0.0.0-20240916204253-42ee18b96377/go.mod h1:kNa9WdvYnzFwC79zRpLRMJbdEFlhyM5RPFBBZp/wWH8=
 golang.org/x/exp v0.0.0-20240909161429-701f63a606c0 h1:e66Fs6Z+fZTbFBAxKfP3PALWBtpfqks2bwGcexMxgtk=
 golang.org/x/exp v0.0.0-20240909161429-701f63a606c0/go.mod h1:2TbTHSBQa924w8M6Xs1QcRcFwyucIwBGpK1p2f1YFFY=
 golang.org/x/image v0.20.0 h1:7cVCUjQwfL18gyBJOmYvptfSHS8Fb3YUDtfLIZ7Nbpw=

main.go

@@ -61,7 +61,7 @@ func Main() (retcode int) { //nolint:funlen // we do have quite a lot of flags a
 	historyFile := flag.String("history", defaultHistoryFile, "history `file` to use")
 	maxHistory := flag.Int("max-history", terminal.DefaultHistoryCapacity, "max history `size`, use 0 to disable.")
 	disableLoadSave := flag.Bool("no-load-save", false, "disable load/save of history")
-	unrestrictedIOs := flag.Bool("unrestricted-io", false, "enable unrestricted io (dangerous)")
+	restrictIOs := flag.Bool("restrict-io", false, "restrict IOs (safe mode)")
 	emptyOnly := flag.Bool("empty-only", false, "only allow load()/save() to ./.gr")
 	noAuto := flag.Bool("no-auto", false, "don't auto load/save the state to ./.gr")
 	maxDepth := flag.Int("max-depth", eval.DefaultMaxDepth-1, "Maximum interpreter depth")
@@ -122,7 +122,7 @@ func Main() (retcode int) { //nolint:funlen // we do have quite a lot of flags a
 	c := extensions.Config{
 		HasLoad:           !*disableLoadSave,
 		HasSave:           !*disableLoadSave,
-		UnrestrictedIOs:   *unrestrictedIOs,
+		UnrestrictedIOs:   !*restrictIOs,
 		LoadSaveEmptyOnly: *emptyOnly,
 	}
 	err := extensions.Init(&c)

main_test.txtar

@@ -146,17 +146,17 @@ stderr 'identifier not found: save'
 !grol -no-load-save -c 'load("foo.gr")'
 stderr 'identifier not found: load'
 
-!grol -c 'save("/tmp/foo.gr"); load("/tmp/foo.gr")'
+!grol -restrict-io -c 'save("/tmp/foo.gr"); load("/tmp/foo.gr")'
 stderr 'invalid character in filename "/tmp/foo.gr": /'
 
-grol -c 'load("fib_50")'
+grol -restrict-io -c 'load("fib_50")'
 stdout '^12586269025\n$'
 stderr 'Read/evaluated: fib_50.gr'
 
-!grol -c 'load("./fib_50.gr")'
+!grol -restrict-io -c 'load("./fib_50.gr")'
 stderr 'invalid character in filename "./fib_50.gr": \.'
 
-grol -unrestricted-io -c 'load("./fib_50.gr")'
+grol -c 'load("./fib_50.gr")'
 stdout '^12586269025\n$'
 stderr 'Read/evaluated: ./fib_50.gr'
 

repl/repl.go

@@ -220,11 +220,11 @@ func Interactive(options Options) int { //nolint:funlen // we do have quite a fe
 	s.MaxDepth = options.MaxDepth
 	s.MaxValueLen = options.MaxValueLen // 0 is unlimited so ok to copy as is.
 	term, err := terminal.Open(context.Background())
-	ctx := term.Context
 	if err != nil {
 		return log.FErrf("Error creating readline: %v", err)
 	}
 	defer term.Close()
+	s.Term = term
 	s.Out = term.Out
 	autoComplete := NewCompletion()
 	tokInfo := token.Info()
@@ -252,6 +252,7 @@ func Interactive(options Options) int { //nolint:funlen // we do have quite a fe
 	}
 	prev := ""
 	for {
+		var ctx context.Context
 		rd, err := term.ReadLine()
 		if errors.Is(err, io.EOF) {
 			log.Infof("EOF, exiting")
@@ -260,12 +261,13 @@ func Interactive(options Options) int { //nolint:funlen // we do have quite a fe
 		}
 		if errors.Is(err, terminal.ErrUserInterrupt) {
 			log.Debugf("^C from user")
-			ctx, _ = term.ResetInterrupts(context.Background()) //nolint:fatcontext // we only get a new one after the previous one is done.
+			term.ResetInterrupts(context.Background()) // will set ctx in term to be used in next loop's eval.
 			continue
 		}
 		if err != nil {
 			return log.FErrf("Error reading line: %v", err)
 		}
+		ctx = term.Context // context can be changed by shell run command through suspend/resume.
 		log.Debugf("Read: %q", rd)
 		if idx, ok := extractHistoryNumber(rd); ok {
 			h := term.History()

tests/shell.gr

@@ -0,0 +1,9 @@
+
+run("true")
+run("echo", "echoing", "foo")
+
+IsErr("non zero exit", run("false"), "exit status 1")
+
+NoErr("exec captures", exec("false").err, `^exit status 1$`)
+NoErr("exec captures", exec("echo", "-n", "foo").stdout, "^foo$")
+NoErr("exec captures", exec("ls", "/no/such/file").stderr, "No such file or directory")