utils/hostname: handle special case of domain name = "(none)" on linux

Linux systems can return interesting values when the domain name is
unset, like "(none)" or an empty string. To handle these, hostname.go is
forked with special Hostname(), DomainName() and RegionName()
implementations for Linux and the original implementations for other
OSes.

diff --git a/utils/hostname/hostname.go b/utils/hostname/hostname.go
index 65431fb9fb71a8961428bc536f4ade7f9e3f144c..a46c31ef069d7400f06be58b699a85f25acda71f 100644 (file)
--- a/utils/hostname/hostname.go
+++ b/utils/hostname/hostname.go
@@ -1,83 +1,28 @@
-//go:build !darwin && !openbsd
+//go:build !linux
 
 package hostname
 
 import (
-       "fmt"
        "strings"
-       "sync"
-       "syscall"
-)
 
-type i8 = interface {
-       int8 | uint8
-}
+       "go.fuhry.dev/runtime/constants"
+)
 
-var utsname syscall.Utsname
-var utsnameOnce sync.Once
+var defaultDomainName = constants.DefaultHostDomain
 
 func Hostname() string {
-       return strings.Split(nodeName(), ".")[0]
+       fqdn := Fqdn()
+       return strings.Split(fqdn, ".")[0]
 }
 
 func DomainName() string {
-       uname := uname()
-
-       domainName := int8ToString(uname.Domainname)
-       if domainName != "(none)" {
-               return domainName
-       }
-
-       nodeName := int8ToString(uname.Nodename)
-       for i, chr := range []byte(nodeName) {
-               if chr == '.' {
-                       return nodeName[i+1:]
-               }
+       fqdn := strings.Split(Fqdn(), ".")
+       if len(fqdn) > 1 {
+               return strings.Join(fqdn[1:], ".")
        }
-
-       err := fmt.Errorf("could not determine domain name from (uname.Nodename=%v) (uname.Domainname=%v)", uname.Nodename, uname.Domainname)
-       panic(err)
+       return defaultDomainName
 }
 
 func RegionName() string {
-       domain := DomainName()
-
-       if domain == "" {
-               panic("domain string is empty")
-       }
-
-       return strings.Split(domain, ".")[0]
-}
-
-func Fqdn() string {
-       return strings.Join([]string{Hostname(), DomainName()}, ".")
-}
-
-func uname() syscall.Utsname {
-       utsnameOnce.Do(func() {
-               err := syscall.Uname(&utsname)
-               if err != nil {
-                       panic(err)
-               }
-       })
-
-       return utsname
-}
-
-func nodeName() string {
-       uname := uname()
-
-       return int8ToString(uname.Nodename)
-}
-
-func int8ToString[T i8](ba [65]T) string {
-       bytes := make([]byte, 0)
-       for _, b := range ba {
-               if b == T(0) {
-                       break
-               }
-               bytes = append(bytes, byte(b))
-       }
-
-       return string(bytes)
+       return strings.Split(DomainName(), ".")[0]
 }

diff --git a/utils/hostname/hostname_generic.go b/utils/hostname/hostname_generic.go
new file mode 100644 (file)
index 0000000..e7fc315
--- /dev/null
+++ b/utils/hostname/hostname_generic.go
@@ -0,0 +1,10 @@
+//go:build !linux && !openbsd && !darwin
+
+package hostname
+
+import "runtime"
+
+func Fqdn() string {
+       panic("fqdn is not implemented on your platform (" + runtime.GOOS + ")")
+       return ""
+}

diff --git a/utils/hostname/hostname_linux.go b/utils/hostname/hostname_linux.go
new file mode 100644 (file)
index 0000000..19aaee3
--- /dev/null
+++ b/utils/hostname/hostname_linux.go
@@ -0,0 +1,86 @@
+//go:build linux
+
+package hostname
+
+import (
+       "fmt"
+       "strings"
+       "sync"
+       "syscall"
+)
+
+type i8 = interface {
+       int8 | uint8
+}
+
+var utsname syscall.Utsname
+var utsnameOnce sync.Once
+
+func Hostname() string {
+       return strings.Split(nodeName(), ".")[0]
+}
+
+func DomainName() string {
+       uname := uname()
+
+       domainName := int8ToString(uname.Domainname)
+       if domainName != "(none)" {
+               return domainName
+       }
+
+       nodeName := int8ToString(uname.Nodename)
+       for i, chr := range []byte(nodeName) {
+               if chr == '.' {
+                       return nodeName[i+1:]
+               }
+       }
+
+       err := fmt.Errorf(
+               "could not determine domain name from (uname.Nodename=%v) (uname.Domainname=%v)",
+               int8ToString(uname.Nodename),
+               int8ToString(uname.Domainname))
+       panic(err)
+}
+
+func RegionName() string {
+       domain := DomainName()
+
+       if domain == "" {
+               panic("domain string is empty")
+       }
+
+       return strings.Split(domain, ".")[0]
+}
+
+func Fqdn() string {
+       return strings.Join([]string{Hostname(), DomainName()}, ".")
+}
+
+func uname() syscall.Utsname {
+       utsnameOnce.Do(func() {
+               err := syscall.Uname(&utsname)
+               if err != nil {
+                       panic(err)
+               }
+       })
+
+       return utsname
+}
+
+func nodeName() string {
+       uname := uname()
+
+       return int8ToString(uname.Nodename)
+}
+
+func int8ToString[T i8](ba [65]T) string {
+       bytes := make([]byte, 0)
+       for _, b := range ba {
+               if b == T(0) {
+                       break
+               }
+               bytes = append(bytes, byte(b))
+       }
+
+       return string(bytes)
+}

diff --git a/utils/hostname/hostname_macos.go b/utils/hostname/hostname_macos.go
index 73337bd4f58bc83f62d38e11f63f70ee998bf8dd..c2618534af502ad14ed4f74d86808f7200cfc788 100644 (file)
--- a/utils/hostname/hostname_macos.go
+++ b/utils/hostname/hostname_macos.go
@@ -11,13 +11,10 @@ import (
        "strings"
        "time"
 
-       "go.fuhry.dev/runtime/constants"
        "go.fuhry.dev/runtime/utils/log"
        "howett.net/plist"
 )
 
-var defaultDomainName = constants.DefaultHostDomain
-
 const (
        systemPreferencesPlist = "/Library/Preferences/SystemConfiguration/preferences.plist"
 )
@@ -44,23 +41,6 @@ type systemPrefs_System_System struct {
        ComputerNameEncoding int    `plist:"ComputerNameEncoding"`
 }
 
-func Hostname() string {
-       fqdn := Fqdn()
-       return strings.Split(fqdn, ".")[0]
-}
-
-func DomainName() string {
-       fqdn := strings.Split(Fqdn(), ".")
-       if len(fqdn) > 1 {
-               return strings.Join(fqdn[1:], ".")
-       }
-       return defaultDomainName
-}
-
-func RegionName() string {
-       return strings.Split(DomainName(), ".")[0]
-}
-
 func Fqdn() string {
        dnsFqdn, dnsErr := fqdnFromDns()
        if dnsErr == nil {

diff --git a/utils/hostname/hostname_openbsd.go b/utils/hostname/hostname_openbsd.go
index caf8ebe2619c526d155d5fb0ac6eeaf8ed90a9c9..32476398e42b297dad7fdeb351712f7594e8e4c9 100644 (file)
--- a/utils/hostname/hostname_openbsd.go
+++ b/utils/hostname/hostname_openbsd.go
@@ -11,30 +11,11 @@ import (
        "strings"
        "time"
 
-       "go.fuhry.dev/runtime/constants"
        "go.fuhry.dev/runtime/utils/log"
 )
 
-var defaultDomainName = constants.DefaultHostDomain
 var cachedFqdn string
 
-func Hostname() string {
-       fqdn := Fqdn()
-       return strings.Split(fqdn, ".")[0]
-}
-
-func DomainName() string {
-       fqdn := strings.Split(Fqdn(), ".")
-       if len(fqdn) > 1 {
-               return strings.Join(fqdn[1:], ".")
-       }
-       return defaultDomainName
-}
-
-func RegionName() string {
-       return strings.Split(DomainName(), ".")[0]
-}
-
 func Fqdn() string {
        if cachedFqdn != "" {
                return cachedFqdn