executils.go

// This file is part of arduino-cli.
//
// Copyright 2020 ARDUINO SA (http://www.arduino.cc/)
//
// This software is released under the GNU General Public License version 3,
// which covers the main part of arduino-cli.
// The terms of this license can be found at:
// https://www.gnu.org/licenses/gpl-3.0.en.html
//
// You can be released from the requirements of the above licenses by purchasing
// a commercial license. Buying such a license is mandatory if you want to
// modify or otherwise use the software for commercial activities involving the
// Arduino software without disclosing the source code of your own applications.
// To purchase a commercial license, send an email to license@arduino.cc.

package executils

import (
"bytes"
"io"
"os/exec"

"github.com/arduino/arduino-cli/i18n"
)

vartr=i18n.Tr

// PipeCommands executes the commands received as input by feeding the output of
// one to the input of the other, exactly like Unix Pipe (|).
// Returns the output of the final command and the eventual error.
//
// code inspired by https://gist.github.com/tyndyll/89fbb2c2273f83a074dc
funcPipeCommands(commands...*exec.Cmd) ([]byte, error) {
varerrorBuffer, outputBuffer bytes.Buffer
pipeStack:=make([]*io.PipeWriter, len(commands)-1)
i:=0
for ; i<len(commands)-1; i++ {
stdinPipe, stdoutPipe:=io.Pipe()
commands[i].Stdout=stdoutPipe
commands[i].Stderr=&errorBuffer
commands[i+1].Stdin=stdinPipe
pipeStack[i] =stdoutPipe
 }
commands[i].Stdout=&outputBuffer
commands[i].Stderr=&errorBuffer

iferr:=call(commands, pipeStack); err!=nil {
returnnil, err
 }

returnoutputBuffer.Bytes(), nil
}

funccall(stack []*exec.Cmd, pipes []*io.PipeWriter) (errerror) {
ifstack[0].Process==nil {
iferr=stack[0].Start(); err!=nil {
returnerr
 }
 }
iflen(stack) >1 {
iferr=stack[1].Start(); err!=nil {
returnerr
 }
deferfunc() {
pipes[0].Close()
err=call(stack[1:], pipes[1:])
 }()
 }
returnstack[0].Wait()
}

// TellCommandNotToSpawnShell avoids that the specified Cmd display a small
// command prompt while runnning on Windows. It has no effects on other OS.
funcTellCommandNotToSpawnShell(cmd*exec.Cmd) {
tellCommandNotToSpawnShell(cmd)
}