go.chromium.org/luci@v0.0.0-20240309015107-7cdc2e660f33/auth/internal/terminal.go (about)

     1  // Copyright 2023 The LUCI Authors.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //      http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  //
    15  //go:build !windows
    16  // +build !windows
    17  
    18  package internal
    19  
    20  import (
    21  	"fmt"
    22  	"os"
    23  
    24  	"github.com/xo/terminfo"
    25  )
    26  
    27  // EnableVirtualTerminal is a dummy function on unix systems that always
    28  // returns supported=true.
    29  func EnableVirtualTerminal() (supported bool, done func()) {
    30  	return true, func() {}
    31  }
    32  
    33  // IsDumbTerminal determines if the current terminal supports CursorUp and CursorDown
    34  // control characters.
    35  func IsDumbTerminal() bool {
    36  	ti, err := terminfo.LoadFromEnv()
    37  	if err != nil {
    38  		fmt.Fprintf(os.Stderr, "Error: %s, couldn't load terminal info from terminfo/\n", err.Error())
    39  		return true
    40  	}
    41  	return ti.Strings[terminfo.CursorDown] == nil || ti.Strings[terminfo.CursorUp] == nil
    42  }