unix: add Uname on FreeBSD

FreeBSD doesn't have a uname syscall but the information can be
retrieved using sysctls the same way as on Darwin.

Change-Id: I824c42490d1feed3f1ad3823427c01dd3e5ea3c1
Reviewed-on: https://go-review.googlesource.com/79918
Run-TryBot: Tobias Klauser <tobias.klauser@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

unix/syscall_freebsd.go

@@ -396,6 +396,52 @@ func IoctlGetTermios(fd int, req uint) (*Termios, error) {
 	return &value, err
 }
 
+func Uname(uname *Utsname) error {
+	mib := []_C_int{CTL_KERN, KERN_OSTYPE}
+	n := unsafe.Sizeof(uname.Sysname)
+	if err := sysctl(mib, &uname.Sysname[0], &n, nil, 0); err != nil {
+		return err
+	}
+
+	mib = []_C_int{CTL_KERN, KERN_HOSTNAME}
+	n = unsafe.Sizeof(uname.Nodename)
+	if err := sysctl(mib, &uname.Nodename[0], &n, nil, 0); err != nil {
+		return err
+	}
+
+	mib = []_C_int{CTL_KERN, KERN_OSRELEASE}
+	n = unsafe.Sizeof(uname.Release)
+	if err := sysctl(mib, &uname.Release[0], &n, nil, 0); err != nil {
+		return err
+	}
+
+	mib = []_C_int{CTL_KERN, KERN_VERSION}
+	n = unsafe.Sizeof(uname.Version)
+	if err := sysctl(mib, &uname.Version[0], &n, nil, 0); err != nil {
+		return err
+	}
+
+	// The version might have newlines or tabs in it, convert them to
+	// spaces.
+	for i, b := range uname.Version {
+		if b == '\n' || b == '\t' {
+			if i == len(uname.Version)-1 {
+				uname.Version[i] = 0
+			} else {
+				uname.Version[i] = ' '
+			}
+		}
+	}
+
+	mib = []_C_int{CTL_HW, HW_MACHINE}
+	n = unsafe.Sizeof(uname.Machine)
+	if err := sysctl(mib, &uname.Machine[0], &n, nil, 0); err != nil {
+		return err
+	}
+
+	return nil
+}
+
 /*
  * Exposed directly
  */

unix/syscall_freebsd_test.go

@@ -295,3 +295,13 @@ func TestCapRightsSetAndClear(t *testing.T) {
 		t.Fatalf("Wrong rights set")
 	}
 }
+
+func TestUname(t *testing.T) {
+	var utsname unix.Utsname
+	err := unix.Uname(&utsname)
+	if err != nil {
+		t.Fatalf("Uname: %v", err)
+	}
+
+	t.Logf("OS: %s/%s %s", utsname.Sysname[:], utsname.Machine[:], utsname.Release[:])
+}

unix/types_freebsd.go

@@ -36,6 +36,7 @@ package unix
 #include <sys/time.h>
 #include <sys/types.h>
 #include <sys/un.h>
+#include <sys/utsname.h>
 #include <sys/wait.h>
 #include <net/bpf.h>
 #include <net/if.h>
@@ -389,3 +390,7 @@ const (
 // Capabilities
 
 type CapRights C.struct_cap_rights
+
+// Uname
+
+type Utsname C.struct_utsname

unix/zerrors_freebsd_386.go

@@ -351,6 +351,8 @@ const (
 	CSTOP                          = 0x13
 	CSTOPB                         = 0x400
 	CSUSP                          = 0x1a
+	CTL_HW                         = 0x6
+	CTL_KERN                       = 0x1
 	CTL_MAXNAME                    = 0x18
 	CTL_NET                        = 0x4
 	DLT_A429                       = 0xb8
@@ -608,6 +610,7 @@ const (
 	F_UNLCKSYS                     = 0x4
 	F_WRLCK                        = 0x3
 	HUPCL                          = 0x4000
+	HW_MACHINE                     = 0x1
 	ICANON                         = 0x100
 	ICMP6_FILTER                   = 0x12
 	ICRNL                          = 0x100
@@ -944,6 +947,10 @@ const (
 	IXANY                          = 0x800
 	IXOFF                          = 0x400
 	IXON                           = 0x200
+	KERN_HOSTNAME                  = 0xa
+	KERN_OSRELEASE                 = 0x2
+	KERN_OSTYPE                    = 0x1
+	KERN_VERSION                   = 0x4
 	LOCK_EX                        = 0x2
 	LOCK_NB                        = 0x4
 	LOCK_SH                        = 0x1

unix/zerrors_freebsd_amd64.go

@@ -351,6 +351,8 @@ const (
 	CSTOP                          = 0x13
 	CSTOPB                         = 0x400
 	CSUSP                          = 0x1a
+	CTL_HW                         = 0x6
+	CTL_KERN                       = 0x1
 	CTL_MAXNAME                    = 0x18
 	CTL_NET                        = 0x4
 	DLT_A429                       = 0xb8
@@ -608,6 +610,7 @@ const (
 	F_UNLCKSYS                     = 0x4
 	F_WRLCK                        = 0x3
 	HUPCL                          = 0x4000
+	HW_MACHINE                     = 0x1
 	ICANON                         = 0x100
 	ICMP6_FILTER                   = 0x12
 	ICRNL                          = 0x100
@@ -944,6 +947,10 @@ const (
 	IXANY                          = 0x800
 	IXOFF                          = 0x400
 	IXON                           = 0x200
+	KERN_HOSTNAME                  = 0xa
+	KERN_OSRELEASE                 = 0x2
+	KERN_OSTYPE                    = 0x1
+	KERN_VERSION                   = 0x4
 	LOCK_EX                        = 0x2
 	LOCK_NB                        = 0x4
 	LOCK_SH                        = 0x1

unix/zerrors_freebsd_arm.go

@@ -351,6 +351,8 @@ const (
 	CSTOP                          = 0x13
 	CSTOPB                         = 0x400
 	CSUSP                          = 0x1a
+	CTL_HW                         = 0x6
+	CTL_KERN                       = 0x1
 	CTL_MAXNAME                    = 0x18
 	CTL_NET                        = 0x4
 	DLT_A429                       = 0xb8
@@ -615,6 +617,7 @@ const (
 	F_UNLCKSYS                     = 0x4
 	F_WRLCK                        = 0x3
 	HUPCL                          = 0x4000
+	HW_MACHINE                     = 0x1
 	ICANON                         = 0x100
 	ICMP6_FILTER                   = 0x12
 	ICRNL                          = 0x100
@@ -951,6 +954,10 @@ const (
 	IXANY                          = 0x800
 	IXOFF                          = 0x400
 	IXON                           = 0x200
+	KERN_HOSTNAME                  = 0xa
+	KERN_OSRELEASE                 = 0x2
+	KERN_OSTYPE                    = 0x1
+	KERN_VERSION                   = 0x4
 	LOCK_EX                        = 0x2
 	LOCK_NB                        = 0x4
 	LOCK_SH                        = 0x1

unix/ztypes_freebsd_386.go

@@ -539,3 +539,11 @@ const (
 type CapRights struct {
 	Rights [2]uint64
 }
+
+type Utsname struct {
+	Sysname  [256]byte
+	Nodename [256]byte
+	Release  [256]byte
+	Version  [256]byte
+	Machine  [256]byte
+}

unix/ztypes_freebsd_amd64.go

@@ -542,3 +542,11 @@ const (
 type CapRights struct {
 	Rights [2]uint64
 }
+
+type Utsname struct {
+	Sysname  [256]byte
+	Nodename [256]byte
+	Release  [256]byte
+	Version  [256]byte
+	Machine  [256]byte
+}

unix/ztypes_freebsd_arm.go

@@ -542,3 +542,11 @@ const (
 type CapRights struct {
 	Rights [2]uint64
 }
+
+type Utsname struct {
+	Sysname  [256]byte
+	Nodename [256]byte
+	Release  [256]byte
+	Version  [256]byte
+	Machine  [256]byte
+}