From 9e05d631b542393f5ebb0eb3747157c8bd0de635 Mon Sep 17 00:00:00 2001 From: Tianon Gravi Date: Fri, 26 Jul 2019 15:25:23 -0700 Subject: [PATCH] runtime: treat CTRL_CLOSE_EVENT, CTRL_LOGOFF_EVENT, CTRL_SHUTDOWN_EVENT as SIGTERM on Windows This matches the existing behavior of treating CTRL_C_EVENT, CTRL_BREAK_EVENT as a synthesized SIGINT event. See https://docs.microsoft.com/en-us/windows/console/handlerroutine for a good documentation source upstream to confirm these values. As for the usage of these events, the "Timeouts" section of that upstream documentation is important to note, especially the limited window in which to do any cleanup before the program will be forcibly killed (defaults typically 5s, but as low as 500ms, and in many cases configurable system-wide). These events are especially relevant for Windows containers, where these events (particularly `CTRL_SHUTDOWN_EVENT`) are one of the only ways containers can "gracefully" shut down (https://github.com/moby/moby/issues/25982#issuecomment-466804071). This was verified by making a simple `main()` which implements the same code as in `ExampleNotify_allSignals` but in a `for` loop, building a `main.exe`, running that in a container, then doing `docker kill -sTERM` on said container. The program prints `Got signal: SIGTERM`, then exits after the aforementioned timeout, as expected. Behavior before this patch is that the program gets no notification (and thus no output) but still exits after the timeout. Fixes #7479 --- src/os/signal/doc.go | 8 ++++++++ src/runtime/defs_windows.go | 10 +++++++--- src/runtime/defs_windows_386.go | 10 +++++++--- src/runtime/defs_windows_amd64.go | 10 +++++++--- src/runtime/defs_windows_arm.go | 10 +++++++--- src/runtime/os_windows.go | 2 ++ src/syscall/types_windows.go | 7 +++++-- 7 files changed, 43 insertions(+), 14 deletions(-) diff --git a/src/os/signal/doc.go b/src/os/signal/doc.go index 16f49c7ab8be1..2229d36954f09 100644 --- a/src/os/signal/doc.go +++ b/src/os/signal/doc.go @@ -211,6 +211,14 @@ will cause os.Interrupt to be sent on the channel, and the program will not exit. If Reset is called, or Stop is called on all channels passed to Notify, then the default behavior will be restored. +Additionally, if Notify is called, and Windows sends CTRL_CLOSE_EVENT, +CTRL_LOGOFF_EVENT or CTRL_SHUTDOWN_EVENT to the process, Notify will +return syscall.SIGTERM. Unlike Control-C and Control-Break, Notify does +not change process behavior when either CTRL_CLOSE_EVENT, +CTRL_LOGOFF_EVENT or CTRL_SHUTDOWN_EVENT is received - the process will +still get terminated unless it exits. But receiving syscall.SIGTERM will +give the process an opportunity to clean up before termination. + Plan 9 On Plan 9, signals have type syscall.Note, which is a string. Calling diff --git a/src/runtime/defs_windows.go b/src/runtime/defs_windows.go index 9bd910747640e..43f358d56af9f 100644 --- a/src/runtime/defs_windows.go +++ b/src/runtime/defs_windows.go @@ -41,9 +41,13 @@ const ( DUPLICATE_SAME_ACCESS = C.DUPLICATE_SAME_ACCESS THREAD_PRIORITY_HIGHEST = C.THREAD_PRIORITY_HIGHEST - SIGINT = C.SIGINT - CTRL_C_EVENT = C.CTRL_C_EVENT - CTRL_BREAK_EVENT = C.CTRL_BREAK_EVENT + SIGINT = C.SIGINT + SIGTERM = C.SIGTERM + CTRL_C_EVENT = C.CTRL_C_EVENT + CTRL_BREAK_EVENT = C.CTRL_BREAK_EVENT + CTRL_CLOSE_EVENT = C.CTRL_CLOSE_EVENT + CTRL_LOGOFF_EVENT = C.CTRL_LOGOFF_EVENT + CTRL_SHUTDOWN_EVENT = C.CTRL_SHUTDOWN_EVENT CONTEXT_CONTROL = C.CONTEXT_CONTROL CONTEXT_FULL = C.CONTEXT_FULL diff --git a/src/runtime/defs_windows_386.go b/src/runtime/defs_windows_386.go index 8c0d6d8b98fdc..3c5057b86f0b7 100644 --- a/src/runtime/defs_windows_386.go +++ b/src/runtime/defs_windows_386.go @@ -15,9 +15,13 @@ const ( _DUPLICATE_SAME_ACCESS = 0x2 _THREAD_PRIORITY_HIGHEST = 0x2 - _SIGINT = 0x2 - _CTRL_C_EVENT = 0x0 - _CTRL_BREAK_EVENT = 0x1 + _SIGINT = 0x2 + _SIGTERM = 0xF + _CTRL_C_EVENT = 0x0 + _CTRL_BREAK_EVENT = 0x1 + _CTRL_CLOSE_EVENT = 0x2 + _CTRL_LOGOFF_EVENT = 0x5 + _CTRL_SHUTDOWN_EVENT = 0x6 _CONTEXT_CONTROL = 0x10001 _CONTEXT_FULL = 0x10007 diff --git a/src/runtime/defs_windows_amd64.go b/src/runtime/defs_windows_amd64.go index 42a446d3cdfc7..ebb1506e2f50c 100644 --- a/src/runtime/defs_windows_amd64.go +++ b/src/runtime/defs_windows_amd64.go @@ -15,9 +15,13 @@ const ( _DUPLICATE_SAME_ACCESS = 0x2 _THREAD_PRIORITY_HIGHEST = 0x2 - _SIGINT = 0x2 - _CTRL_C_EVENT = 0x0 - _CTRL_BREAK_EVENT = 0x1 + _SIGINT = 0x2 + _SIGTERM = 0xF + _CTRL_C_EVENT = 0x0 + _CTRL_BREAK_EVENT = 0x1 + _CTRL_CLOSE_EVENT = 0x2 + _CTRL_LOGOFF_EVENT = 0x5 + _CTRL_SHUTDOWN_EVENT = 0x6 _CONTEXT_CONTROL = 0x100001 _CONTEXT_FULL = 0x10000b diff --git a/src/runtime/defs_windows_arm.go b/src/runtime/defs_windows_arm.go index 049f5b613a74d..b275b0572a7e7 100644 --- a/src/runtime/defs_windows_arm.go +++ b/src/runtime/defs_windows_arm.go @@ -16,9 +16,13 @@ const ( _DUPLICATE_SAME_ACCESS = 0x2 _THREAD_PRIORITY_HIGHEST = 0x2 - _SIGINT = 0x2 - _CTRL_C_EVENT = 0x0 - _CTRL_BREAK_EVENT = 0x1 + _SIGINT = 0x2 + _SIGTERM = 0xF + _CTRL_C_EVENT = 0x0 + _CTRL_BREAK_EVENT = 0x1 + _CTRL_CLOSE_EVENT = 0x2 + _CTRL_LOGOFF_EVENT = 0x5 + _CTRL_SHUTDOWN_EVENT = 0x6 _CONTEXT_CONTROL = 0x10001 _CONTEXT_FULL = 0x10007 diff --git a/src/runtime/os_windows.go b/src/runtime/os_windows.go index 074ae0f40de8a..9540069e11a75 100644 --- a/src/runtime/os_windows.go +++ b/src/runtime/os_windows.go @@ -894,6 +894,8 @@ func ctrlhandler1(_type uint32) uint32 { switch _type { case _CTRL_C_EVENT, _CTRL_BREAK_EVENT: s = _SIGINT + case _CTRL_CLOSE_EVENT, _CTRL_LOGOFF_EVENT, _CTRL_SHUTDOWN_EVENT: + s = _SIGTERM default: return 0 } diff --git a/src/syscall/types_windows.go b/src/syscall/types_windows.go index 0b839339d2f19..0349f3b180dea 100644 --- a/src/syscall/types_windows.go +++ b/src/syscall/types_windows.go @@ -176,8 +176,11 @@ const ( FILE_MAP_READ = 0x04 FILE_MAP_EXECUTE = 0x20 - CTRL_C_EVENT = 0 - CTRL_BREAK_EVENT = 1 + CTRL_C_EVENT = 0 + CTRL_BREAK_EVENT = 1 + CTRL_CLOSE_EVENT = 2 + CTRL_LOGOFF_EVENT = 5 + CTRL_SHUTDOWN_EVENT = 6 ) const (