Implement ioctl(FIOASYNC)

FIOASYNC and friends are used to send signals when a file is ready for IO.

This may or may not be needed by Nginx. While Nginx does use it, it is unclear
if the code that uses it has any effect.

PiperOrigin-RevId: 201550828
Change-Id: I7ba05a7db4eb2dfffde11e9bd9a35b65b98d7f50

4 files changed, 69 insertions, 0 deletions

diff --git a/pkg/abi/linux/BUILD b/pkg/abi/linux/BUILD
index 693ce0fdd..5d00b66cc 100644
--- a/pkg/abi/linux/BUILD
+++ b/pkg/abi/linux/BUILD
@@ -31,6 +31,7 @@ go_library(
         "elf.go",
         "errors.go",
         "exec.go",
+        "fcntl.go",
         "file.go",
         "fs.go",
         "futex.go",
diff --git a/pkg/abi/linux/fcntl.go b/pkg/abi/linux/fcntl.go
new file mode 100644
index 000000000..f5dbe5199
--- /dev/null
+++ b/pkg/abi/linux/fcntl.go
@@ -0,0 +1,29 @@
+// Copyright 2018 Google Inc.
+//
+// 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
+
+// Comands from linux/fcntl.h.
+const (
+	F_DUPFD         = 0
+	F_DUPFD_CLOEXEC = 1030
+	F_GETFD         = 1
+	F_GETFL         = 3
+	F_GETOWN        = 9
+	F_SETFD         = 2
+	F_SETFL         = 4
+	F_SETLK         = 6
+	F_SETLKW        = 7
+	F_SETOWN        = 8
+)
diff --git a/pkg/abi/linux/ioctl.go b/pkg/abi/linux/ioctl.go
index 35cefbdfc..3ef046562 100644
--- a/pkg/abi/linux/ioctl.go
+++ b/pkg/abi/linux/ioctl.go
@@ -29,6 +29,11 @@ const (
 	TIOCSPTLCK = 0x40045431
 	FIONCLEX   = 0x00005450
 	FIOCLEX    = 0x00005451
+	FIOASYNC   = 0x00005452
+	FIOSETOWN  = 0x00008901
+	SIOCSPGRP  = 0x00008902
+	FIOGETOWN  = 0x00008903
+	SIOCGPGRP  = 0x00008904
 )
 
 // ioctl(2) requests provided by uapi/linux/android/binder.h
diff --git a/pkg/abi/linux/signal.go b/pkg/abi/linux/signal.go
index cd09008b5..fed2a159f 100644
--- a/pkg/abi/linux/signal.go
+++ b/pkg/abi/linux/signal.go
@@ -175,3 +175,37 @@ const (
 	SA_NOMASK      = SA_NODEFER
 	SA_ONESHOT     = SA_RESTARTHAND
 )
+
+// Signal info types.
+const (
+	SI_MASK  = 0xffff0000
+	SI_KILL  = 0 << 16
+	SI_TIMER = 1 << 16
+	SI_POLL  = 2 << 16
+	SI_FAULT = 3 << 16
+	SI_CHLD  = 4 << 16
+	SI_RT    = 5 << 16
+	SI_MESGQ = 6 << 16
+	SI_SYS   = 7 << 16
+)
+
+// SIGPOLL si_codes.
+const (
+	// POLL_IN indicates that data input available.
+	POLL_IN = SI_POLL | 1
+
+	// POLL_OUT indicates that output buffers available.
+	POLL_OUT = SI_POLL | 2
+
+	// POLL_MSG indicates that an input message available.
+	POLL_MSG = SI_POLL | 3
+
+	// POLL_ERR indicates that there was an i/o error.
+	POLL_ERR = SI_POLL | 4
+
+	// POLL_PRI indicates that a high priority input available.
+	POLL_PRI = SI_POLL | 5
+
+	// POLL_HUP indicates that a device disconnected.
+	POLL_HUP = SI_POLL | 6
+)