repeater/internal/config/config.go

106 lines
2.7 KiB
Go

package config
import (
"flag"
"log"
"os"
"path"
"strings"
)
type Config struct {
Bind string
WifiInterface string
HotspotInterface string
WifiBackend string
StationBackend string // "arp", "dhcp", or "hostapd"
DHCPLeasesPath string
ARPTablePath string
SyslogEnabled bool
SyslogPath string
SyslogFilter []string
SyslogSource string
}
// ConsolidateConfig fills an Options struct by reading configuration from
// config files, environment, then command line.
//
// Should be called only one time.
func ConsolidateConfig() (opts *Config, err error) {
// Define defaults options
opts = &Config{
Bind: ":8080",
WifiInterface: "wlan0",
HotspotInterface: "wlan1",
DHCPLeasesPath: "/var/lib/dhcp/dhcpd.leases",
ARPTablePath: "/proc/net/arp",
SyslogEnabled: false,
SyslogPath: "/var/log/messages",
SyslogFilter: []string{"daemon.info wpa_supplicant:", "daemon.info iwd:", "daemon.info hostapd:"},
SyslogSource: "iwd",
}
declareFlags(opts)
// Establish a list of possible configuration file locations
configLocations := []string{
"repeater.conf",
}
if home, err := os.UserConfigDir(); err == nil {
configLocations = append(configLocations, path.Join(home, "repeater", "repeater.conf"))
}
configLocations = append(configLocations, path.Join("etc", "repeater.conf"))
// If config file exists, read configuration from it
for _, filename := range configLocations {
if _, e := os.Stat(filename); !os.IsNotExist(e) {
log.Printf("Loading configuration from %s\n", filename)
err = parseFile(opts, filename)
if err != nil {
return
}
break
}
}
// Then, overwrite that by what is present in the environment
err = parseEnvironmentVariables(opts)
if err != nil {
return
}
// Finaly, command line takes precedence
err = parseCLI(opts)
if err != nil {
return
}
// Validate configuration
if opts.WifiBackend != "iwd" && opts.WifiBackend != "wpasupplicant" {
log.Fatalf("wifi-backend must be set to 'iwd' or 'wpasupplicant' (got: '%s')", opts.WifiBackend)
}
if opts.StationBackend != "arp" && opts.StationBackend != "dhcp" && opts.StationBackend != "hostapd" {
log.Fatalf("station-backend must be set to 'arp', 'dhcp', or 'hostapd' (got: '%s')", opts.StationBackend)
}
return
}
// parseLine treats a config line and place the read value in the variable
// declared to the corresponding flag.
func parseLine(o *Config, line string) (err error) {
fields := strings.SplitN(line, "=", 2)
orig_key := strings.TrimSpace(fields[0])
value := strings.TrimSpace(fields[1])
key := strings.TrimPrefix(orig_key, "REPEATER_")
key = strings.Replace(key, "_", "-", -1)
key = strings.ToLower(key)
err = flag.Set(key, value)
return
}