Merge pull request #104 from xushiwei/log

gsh: exec

gsh/classfile.go

@@ -18,9 +18,11 @@ package gsh
 
 import (
 	"bytes"
+	"errors"
 	"io"
 	"os"
 	"os/exec"
+	"strings"
 )
 
 const (
@@ -42,16 +44,78 @@ func (p *App) initApp() {
 	p.ferr = os.Stderr
 }
 
-// Gop_Exec executes a shell command.
-func (p *App) Gop_Exec(name string, args ...string) error {
+func (p *App) execWith(env []string, name string, args ...string) error {
 	cmd := exec.Command(name, args...)
 	cmd.Stdin = p.fin
 	cmd.Stdout = p.fout
 	cmd.Stderr = p.ferr
-	p.err = cmd.Run()
+	cmd.Env = env
+	p.err = Sys.Run(cmd)
 	return p.err
 }
 
+// Gop_Exec executes a shell command.
+func (p *App) Gop_Exec(name string, args ...string) error {
+	return p.execWith(nil, name, args...)
+}
+
+// Exec executes a shell command with specified environs.
+func (p *App) Exec__0(env map[string]string, name string, args ...string) error {
+	var cmdEnv []string
+	if env != nil {
+		cmdEnv = Setenv__0(Sys.Environ(), env)
+	}
+	return p.execWith(cmdEnv, name, args...)
+}
+
+// Exec executes a shell command.
+func (p *App) Exec__1(name string, args ...string) error {
+	return p.execWith(nil, name, args...)
+}
+
+// Exec executes a shell command line with $env variables support.
+//   - exec "GOP_GOCMD=tinygo gop run ."
+//   - exec "ls -l $HOME"
+func (p *App) Exec__2(cmdline string) error {
+	var iCmd = -1
+	var items = strings.Fields(cmdline)
+	var env []string
+	var initEnv = func() {
+		env = Sys.Environ()
+		if iCmd > 0 {
+			env = Setenv__2(env, items[:iCmd])
+		}
+	}
+	var mapping = func(name string) string {
+		if env == nil {
+			initEnv()
+		}
+		return Getenv(env, name)
+	}
+	for i, e := range items {
+		pos := strings.IndexAny(e, "=$")
+		if pos >= 0 && e[pos] == '=' {
+			if strings.IndexByte(e[pos+1:], '$') >= 0 {
+				items[i] = Sys.ExpandEnv(e)
+			}
+			continue
+		}
+		if iCmd < 0 {
+			iCmd = i
+		}
+		if pos >= 0 {
+			items[i] = os.Expand(e, mapping)
+		}
+	}
+	if iCmd < 0 {
+		return errors.New("exec: no command")
+	}
+	if env == nil && iCmd > 0 {
+		initEnv()
+	}
+	return p.execWith(env, items[iCmd], items[iCmd+1:]...)
+}
+
 // LastErr returns error of last command execution.
 func (p *App) LastErr() error {
 	return p.err

gsh/env.go

@@ -0,0 +1,111 @@
+/*
+ Copyright 2024 Qiniu Limited (qiniu.com)
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+     http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+*/
+
+package gsh
+
+import (
+	"os"
+	"os/exec"
+	"strings"
+)
+
+// -----------------------------------------------------------
+
+// Setenv overwrites environments with specified env.
+func Setenv__0(ret []string, env map[string]string) []string {
+	for k, v := range env {
+		nameEq := k + "="
+		ret = setenv(ret, nameEq+v, len(nameEq))
+	}
+	return ret
+}
+
+// Setenv overwrites environments with specified (name, val) pair.
+func Setenv__1(ret []string, name, val string) []string {
+	nameEq := name + "="
+	return setenv(ret, nameEq+val, len(nameEq))
+}
+
+func setenv(ret []string, pair string, idxVal int) []string {
+	nameEq := pair[:idxVal]
+	for i, e := range ret {
+		if strings.HasPrefix(e, nameEq) {
+			ret[i] = pair
+			return ret
+		}
+	}
+	return append(ret, pair)
+}
+
+// Setenv overwrites environments with specified "name=val" pairs.
+func Setenv__2(ret []string, env []string) []string {
+	for _, pair := range env {
+		pos := strings.IndexByte(pair, '=')
+		if pos > 0 {
+			ret = setenv(ret, pair, pos+1)
+		}
+	}
+	return ret
+}
+
+// Getenv retrieves the value of the environment variable named by the key.
+// It returns the value, which will be empty if the variable is not present.
+// To distinguish between an empty value and an unset value, use LookupEnv.
+func Getenv(env []string, name string) string {
+	nameEq := name + "="
+	for _, e := range env {
+		if strings.HasPrefix(e, nameEq) {
+			return e[len(nameEq):]
+		}
+	}
+	return ""
+}
+
+// -----------------------------------------------------------
+
+type OS interface {
+	// Environ returns a copy of strings representing the environment,
+	// in the form "key=value".
+	Environ() []string
+
+	// ExpandEnv replaces ${var} or $var in the string according to the values
+	// of the current environment variables. References to undefined
+	// variables are replaced by the empty string.
+	ExpandEnv(s string) string
+
+	// Run starts the specified command and waits for it to complete.
+	Run(c *exec.Cmd) error
+}
+
+// -----------------------------------------------------------
+
+type defaultOS struct{}
+
+func (p defaultOS) Environ() []string {
+	return os.Environ()
+}
+
+func (p defaultOS) ExpandEnv(s string) string {
+	return os.ExpandEnv(s)
+}
+
+func (p defaultOS) Run(c *exec.Cmd) error {
+	return c.Run()
+}
+
+var Sys OS = defaultOS{}
+
+// -----------------------------------------------------------