c/libuv
1
0
Fork 0
mirror of https://github.com/libuv/libuv synced 2025-03-28 21:13:16 +00:00
Code Issues Packages Projects Releases Wiki Activity

win,signal: fix potential deadlock

Browse Source 
Trying to remove the controller from the controller handle itself
leads to deadlock. Fix it by always having the global signal handler
engaged.

Ref: https://github.com/nodejs/node/issues/10165
PR-URL: https://github.com/libuv/libuv/pull/1168
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>
This commit is contained in:
Bartosz Sosnowski 2016-12-12 11:34:42 +01:00 committed by Saúl Ibarra Corretgé
parent c8ab24bb92
commit c66f265b5d
3 changed files with 38 additions and 117 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

118
src/win/signal.c
View File

@ -30,12 +30,14 @@
RB_HEAD(uv_signal_tree_s, uv_signal_s);
static struct uv_signal_tree_s uv__signal_tree = RB_INITIALIZER(uv__signal_tree);
static ssize_t volatile uv__signal_control_handler_refs = 0;
static CRITICAL_SECTION uv__signal_lock;
static BOOL WINAPI uv__signal_control_handler(DWORD type);
void uv_signals_init() {
InitializeCriticalSection(&uv__signal_lock);
if (!SetConsoleCtrlHandler(uv__signal_control_handler, TRUE))
abort();
}
@ -125,102 +127,6 @@ static BOOL WINAPI uv__signal_control_handler(DWORD type) {
}
static int uv__signal_register_control_handler() {
/* When this function is called, the uv__signal_lock must be held. */
/* If the console control handler has already been hooked, just add a */
/* reference. */
if (uv__signal_control_handler_refs > 0) {
uv__signal_control_handler_refs++;
return 0;
}
if (!SetConsoleCtrlHandler(uv__signal_control_handler, TRUE))
return GetLastError();
uv__signal_control_handler_refs++;
return 0;
}
static void uv__signal_unregister_control_handler() {
/* When this function is called, the uv__signal_lock must be held. */
BOOL r;
/* Don't unregister if the number of console control handlers exceeds one. */
/* Just remove a reference in that case. */
if (uv__signal_control_handler_refs > 1) {
uv__signal_control_handler_refs--;
return;
}
assert(uv__signal_control_handler_refs == 1);
r = SetConsoleCtrlHandler(uv__signal_control_handler, FALSE);
/* This should never fail; if it does it is probably a bug in libuv. */
assert(r);
uv__signal_control_handler_refs--;
}
static int uv__signal_register(int signum) {
switch (signum) {
case SIGINT:
case SIGBREAK:
case SIGHUP:
return uv__signal_register_control_handler();
case SIGWINCH:
/* SIGWINCH is generated in tty.c. No need to register anything. */
return 0;
case SIGILL:
case SIGABRT_COMPAT:
case SIGFPE:
case SIGSEGV:
case SIGTERM:
case SIGABRT:
/* Signal is never raised. */
return 0;
default:
/* Invalid signal. */
return ERROR_INVALID_PARAMETER;
}
}
static void uv__signal_unregister(int signum) {
switch (signum) {
case SIGINT:
case SIGBREAK:
case SIGHUP:
uv__signal_unregister_control_handler();
return;
case SIGWINCH:
/* SIGWINCH is generated in tty.c. No need to unregister anything. */
return;
case SIGILL:
case SIGABRT_COMPAT:
case SIGFPE:
case SIGSEGV:
case SIGTERM:
case SIGABRT:
/* Nothing is registered for this signal. */
return;
default:
/* Libuv bug. */
assert(0 && "Invalid signum");
return;
}
}
int uv_signal_init(uv_loop_t* loop, uv_signal_t* handle) {
uv_req_t* req;
@ -247,8 +153,6 @@ int uv_signal_stop(uv_signal_t* handle) {
EnterCriticalSection(&uv__signal_lock);
uv__signal_unregister(handle->signum);
removed_handle = RB_REMOVE(uv_signal_tree_s, &uv__signal_tree, handle);
assert(removed_handle == handle);
@ -262,14 +166,9 @@ int uv_signal_stop(uv_signal_t* handle) {
int uv_signal_start(uv_signal_t* handle, uv_signal_cb signal_cb, int signum) {
int err;
/* If the user supplies signum == 0, then return an error already. If the */
/* signum is otherwise invalid then uv__signal_register will find out */
/* eventually. */
if (signum == 0) {
/* Test for invalid signal values. */
if (signum != SIGWINCH && (signum <= 0 || signum >= NSIG))
return UV_EINVAL;
}
/* Short circuit: if the signal watcher is already watching {signum} don't */
/* go through the process of deregistering and registering the handler. */
@ -289,13 +188,6 @@ int uv_signal_start(uv_signal_t* handle, uv_signal_cb signal_cb, int signum) {
EnterCriticalSection(&uv__signal_lock);
err = uv__signal_register(signum);
if (err) {
/* Uh-oh, didn't work. */
LeaveCriticalSection(&uv__signal_lock);
return uv_translate_sys_error(err);
}
handle->signum = signum;
RB_INSERT(uv_signal_tree_s, &uv__signal_tree, handle);

2
test/test-list.h
View File

@ -346,6 +346,7 @@ TEST_DECLARE (listen_no_simultaneous_accepts)
TEST_DECLARE (fs_stat_root)
TEST_DECLARE (spawn_with_an_odd_path)
TEST_DECLARE (ipc_listen_after_bind_twice)
TEST_DECLARE (win32_signum_number)
#else
TEST_DECLARE (emfile)
TEST_DECLARE (close_fd)
@ -695,6 +696,7 @@ TASK_LIST_START
TEST_ENTRY (fs_stat_root)
TEST_ENTRY (spawn_with_an_odd_path)
TEST_ENTRY (ipc_listen_after_bind_twice)
TEST_ENTRY (win32_signum_number)
#else
TEST_ENTRY (emfile)
TEST_ENTRY (close_fd)

35
test/test-signal.c
View File

@ -19,13 +19,40 @@
* IN THE SOFTWARE.
*/
/* This test does not pretend to be cross-platform. */
#ifndef _WIN32
#include "uv.h"
#include "task.h"
/* For Windows we test only signum handling */
#ifdef _WIN32
static void signum_test_cb(uv_signal_t* handle, int signum) {
FATAL("signum_test_cb should not be called");
}
TEST_IMPL(win32_signum_number) {
uv_signal_t signal;
uv_loop_t* loop;
loop = uv_default_loop();
uv_signal_init(loop, &signal);
ASSERT(uv_signal_start(&signal, signum_test_cb, 0) == UV_EINVAL);
ASSERT(uv_signal_start(&signal, signum_test_cb, SIGINT) == 0);
ASSERT(uv_signal_start(&signal, signum_test_cb, SIGBREAK) == 0);
ASSERT(uv_signal_start(&signal, signum_test_cb, SIGHUP) == 0);
ASSERT(uv_signal_start(&signal, signum_test_cb, SIGWINCH) == 0);
ASSERT(uv_signal_start(&signal, signum_test_cb, SIGILL) == 0);
ASSERT(uv_signal_start(&signal, signum_test_cb, SIGABRT_COMPAT) == 0);
ASSERT(uv_signal_start(&signal, signum_test_cb, SIGFPE) == 0);
ASSERT(uv_signal_start(&signal, signum_test_cb, SIGSEGV) == 0);
ASSERT(uv_signal_start(&signal, signum_test_cb, SIGTERM) == 0);
ASSERT(uv_signal_start(&signal, signum_test_cb, SIGABRT) == 0);
ASSERT(uv_signal_start(&signal, signum_test_cb, -1) == UV_EINVAL);
ASSERT(uv_signal_start(&signal, signum_test_cb, NSIG) == UV_EINVAL);
ASSERT(uv_signal_start(&signal, signum_test_cb, 1024) == UV_EINVAL);
MAKE_VALGRIND_HAPPY();
return 0;
}
#else
#include <errno.h>
#include <signal.h>
#include <stdarg.h>