parse_config.go

/*
 * Copyright (c) 2022 Red Hat, Inc.
 * SPDX-License-Identifier: GPL-2.0-or-later
 */

package main

import (
	"fmt"
	"regexp"
	"strconv"
	"strings"
)

// Kernel version item
type kversion struct {
	Version      int64
	Patchlevel   int64
	Sublevel     int64
	Extraversion string
}

// Given a config autogenerated file into the kernel source tree, returns
// the list of kernel config options
func parse_config(kconfig []string) map[string]string {

	res := make(map[string]string)
	for _, line := range kconfig {
		if strings.Contains(line, "#define CONFIG_") {
			tmp := strings.ReplaceAll(line, "#define CONFIG_", "")
			items := strings.Split(tmp, " ")
			res[items[0]] = items[1]
		}
	}
	return res
}

// Parses a makefile and returns the current kernel version
func get_version(makefile []string) (kversion, error) {
	var state int = 0
	var v kversion

	for _, line := range makefile {
		if match, _ := regexp.MatchString("VERSION[ \t]*=[ \t]*[0-9]+", line); match && state == 0 {
			re := regexp.MustCompile(`VERSION[ \t]*=[ \t]*([0-9]+)`)
			tmp, err := strconv.ParseInt(re.ReplaceAllString(line, "$1"), 10, 64)
			if err != nil {
				panic(err)
			}
			v.Version = tmp
			state = 1
		}
		if match, _ := regexp.MatchString("PATCHLEVEL[ \t]*=[ \t]*[0-9]+", line); match && state == 1 {
			re := regexp.MustCompile(`PATCHLEVEL[ \t]*=[ \t]*([0-9]+)`)
			tmp, err := strconv.ParseInt(re.ReplaceAllString(line, "$1"), 10, 64)
			if err != nil {
				panic(err)
			}
			v.Patchlevel = tmp
			state = 2
		}
		if match, _ := regexp.MatchString("SUBLEVEL[ \t]*=[ \t]*[0-9]+", line); match && state == 2 {
			re := regexp.MustCompile(`SUBLEVEL[ \t]*=[ \t]*([0-9]+)`)
			tmp, err := strconv.ParseInt(re.ReplaceAllString(line, "$1"), 10, 64)
			if err != nil {
				panic(err)
			}
			v.Sublevel = tmp
			state = 3
		}
		if match, _ := regexp.MatchString("EXTRAVERSION[ \t]*=[ \t]*.*", line); match && state == 3 {
			re := regexp.MustCompile(`EXTRAVERSION[ \t]*=[ \t]*(.*)`)
			v.Extraversion = re.ReplaceAllString(line, "$1")
			state = 4
			break
		}
	}
	if state == 4 {
		return v, nil
	}
	return v, fmt.Errorf("can't parse makefile (%d)", state)

}