Support `NO_COLOR' environment variable

Suppress color if the `NO_COLOR' environment variable is is present.
For more information, visit `https://no-color.org/'.

alogview.go

@@ -86,20 +86,21 @@ func main() {
	if len(*s) > 0 {
		adbargs = append(adbargs, "-s", *s)
	}
	_, suppresscolor := os.LookupEnv("NO_COLOR")
	if len(flag.Args()) == 0 {
		processLogs(func(line *logLine) bool { return true })
		processLogs(func(line *logLine) bool { return true }, suppresscolor)
	} else {
		packages := make(map[string]bool)

		for _, pkg := range os.Args {
			packages[pkg] = true
		}
		pids := getProcs(packages)
		processLogs(func(line *logLine) bool { return filterByPackages(line, packages, pids) })
		processLogs(func(line *logLine) bool { return filterByPackages(line, packages, pids) }, suppresscolor)
	}
}

func processLogs(filter filter) {
func processLogs(filter filter, suppresscolor bool) {
	r, w := io.Pipe()

	go runADB(w, "logcat")
@@ -119,7 +120,11 @@ func processLogs(filter filter) {
			continue
		}
		if filter(msg) {
			fmt.Printf("%s%s%s\n", colorForLevel(msg.level), line, reset)
			if suppresscolor {
				fmt.Printf("%s\n", line)
			} else {
				fmt.Printf("%s%s%s\n", colorForLevel(msg.level), line, reset)
			}
		}
	}
}