1 files changed, 55 insertions, 0 deletions
diff --git a/pkg/abi/linux/dev.go b/pkg/abi/linux/dev.go
new file mode 100644
index 000000000..421e11256
--- /dev/null
+++ b/pkg/abi/linux/dev.go
@@ -0,0 +1,55 @@
+// Copyright 2018 The gVisor Authors.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package linux
+
+// MakeDeviceID encodes a major and minor device number into a single device ID.
+//
+// Format (see linux/kdev_t.h:new_encode_dev):
+//
+// Bits 7:0   - minor bits 7:0
+// Bits 19:8  - major bits 11:0
+// Bits 31:20 - minor bits 19:8
+func MakeDeviceID(major uint16, minor uint32) uint32 {
+	return (minor & 0xff) | ((uint32(major) & 0xfff) << 8) | ((minor >> 8) << 20)
+}
+
+// DecodeDeviceID decodes a device ID into major and minor device numbers.
+func DecodeDeviceID(rdev uint32) (uint16, uint32) {
+	major := uint16((rdev >> 8) & 0xfff)
+	minor := (rdev & 0xff) | ((rdev >> 20) << 8)
+	return major, minor
+}
+
+// Character device IDs.
+//
+// See Documentations/devices.txt and uapi/linux/major.h.
+const (
+	// TTYAUX_MAJOR is the major device number for alternate TTY devices.
+	TTYAUX_MAJOR = 5
+
+	// UNIX98_PTY_MASTER_MAJOR is the initial major device number for
+	// Unix98 PTY masters.
+	UNIX98_PTY_MASTER_MAJOR = 128
+
+	// UNIX98_PTY_SLAVE_MAJOR is the initial major device number for
+	// Unix98 PTY slaves.
+	UNIX98_PTY_SLAVE_MAJOR = 136
+)
+
+// Minor device numbers for TTYAUX_MAJOR.
+const (
+	// PTMX_MINOR is the minor device number for /dev/ptmx.
+	PTMX_MINOR = 2
+)