test: test that uv_close() doesn't corrupt QUEUE

The test adds all types of handles, that were known to be affected by
QUEUE_REMOVE()-within-QUEUE_FOREACH() bug, to a loop.
It then calls uv_close() to trigger QUEUE_REMOVE()-within-QUEUE_FOREACH() case
and checks whether a particular QUEUE is corrupted or not.

Restrict the test to Linux only for now as it fails on other platforms
for various reasons.

PR-URL: https://github.com/libuv/libuv/pull/621
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>

Makefile.am

@@ -200,6 +200,7 @@ test_run_tests_SOURCES = test/blackhole-server.c \
                          test/test-poll-closesocket.c \
                          test/test-poll.c \
                          test/test-process-title.c \
+                         test/test-queue-foreach-delete.c \
                          test/test-ref.c \
                          test/test-run-nowait.c \
                          test/test-run-once.c \

test/test-list.h

@@ -337,6 +337,7 @@ HELPER_DECLARE (tcp6_echo_server)
 HELPER_DECLARE (udp4_echo_server)
 HELPER_DECLARE (pipe_echo_server)
 
+TEST_DECLARE   (queue_foreach_delete)
 
 TASK_LIST_START
   TEST_ENTRY_CUSTOM (platform_output, 0, 1, 5000)
@@ -720,6 +721,9 @@ TASK_LIST_START
   TEST_ENTRY  (dlerror)
   TEST_ENTRY  (ip4_addr)
   TEST_ENTRY  (ip6_addr_link_local)
+
+  TEST_ENTRY  (queue_foreach_delete)
+
 #if 0
   /* These are for testing the test runner. */
   TEST_ENTRY  (fail_always)

test/test-queue-foreach-delete.c

@@ -0,0 +1,143 @@
+/* Copyright The libuv project and contributors. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "uv.h"
+#include "task.h"
+
+#include <string.h>
+
+
+/*
+ * The idea behind the test is as follows.
+ * Certain handle types are stored in a queue internally.
+ * Extra care should be taken for removal of a handle from the queue while iterating over the queue.
+ * (i.e., QUEUE_REMOVE() called within QUEUE_FOREACH())
+ * This usually happens when someone closes or stops a handle from within its callback.
+ * So we need to check that we haven't screwed the queue on close/stop.
+ * To do so we do the following (for each handle type):
+ *  1. Create and start 3 handles (#0, #1, and #2).
+ *
+ *     The queue after the start() calls:
+ *     ..=> [queue head] <=> [handle] <=> [handle #1] <=> [handle] <=..
+ *
+ *  2. Trigger handles to fire (for uv_idle_t, uv_prepare_t, and uv_check_t there is nothing to do).
+ *
+ *  3. In the callback for the first-executed handle (#0 or #2 depending on handle type)
+ *     stop the handle and the next one (#1).
+ *     (for uv_idle_t, uv_prepare_t, and uv_check_t callbacks are executed in the reverse order as they are start()'ed,
+ *     so callback for handle #2 will be called first)
+ *
+ *     The queue after the stop() calls:
+ *                                correct foreach "next"  |
+ *                                                       \/
+ *     ..=> [queue head] <==============================> [handle] <=..
+ *          [          ] <-  [handle] <=> [handle #1]  -> [      ]
+ *                                       /\
+ *                  wrong foreach "next"  |
+ *
+ *  4. The callback for handle #1 shouldn't be called because the handle #1 is stopped in the previous step.
+ *     However, if QUEUE_REMOVE() is not handled properly within QUEUE_FOREACH(), the callback _will_ be called.
+ */
+
+static const unsigned first_handle_number_idle     = 2;
+static const unsigned first_handle_number_prepare  = 2;
+static const unsigned first_handle_number_check    = 2;
+
+
+#define DEFINE_GLOBALS_AND_CBS(name)                                          \
+  static uv_##name##_t (name)[3];                                             \
+  static unsigned name##_cb_calls[3];                                         \
+                                                                              \
+  static void name##2_cb(uv_##name##_t* handle) {                             \
+    ASSERT(handle == &(name)[2]);                                             \
+    if (first_handle_number_##name == 2) {                                    \
+      uv_close((uv_handle_t*)&(name)[2], NULL);                               \
+      uv_close((uv_handle_t*)&(name)[1], NULL);                               \
+    }                                                                         \
+    name##_cb_calls[2]++;                                                     \
+  }                                                                           \
+                                                                              \
+  static void name##1_cb(uv_##name##_t* handle) {                             \
+    ASSERT(handle == &(name)[1]);                                             \
+    ASSERT(0 && "Shouldn't be called" && (&name[0]));                         \
+  }                                                                           \
+                                                                              \
+  static void name##0_cb(uv_##name##_t* handle) {                             \
+    ASSERT(handle == &(name)[0]);                                             \
+    if (first_handle_number_##name == 0) {                                    \
+      uv_close((uv_handle_t*)&(name)[0], NULL);                               \
+      uv_close((uv_handle_t*)&(name)[1], NULL);                               \
+    }                                                                         \
+    name##_cb_calls[0]++;                                                     \
+  }                                                                           \
+                                                                              \
+  static const uv_##name##_cb name##_cbs[] = {                                \
+    (uv_##name##_cb)name##0_cb,                                               \
+    (uv_##name##_cb)name##1_cb,                                               \
+    (uv_##name##_cb)name##2_cb,                                               \
+  };
+
+#define INIT_AND_START(name, loop)                                            \
+  do {                                                                        \
+    size_t i;                                                                 \
+    for (i = 0; i < ARRAY_SIZE(name); i++) {                                  \
+      int r;                                                                  \
+      r = uv_##name##_init((loop), &(name)[i]);                               \
+      ASSERT(r == 0);                                                         \
+                                                                              \
+      r = uv_##name##_start(&(name)[i], name##_cbs[i]);                       \
+      ASSERT(r == 0);                                                         \
+    }                                                                         \
+  } while (0)
+
+#define END_ASSERTS(name)                                                     \
+  do {                                                                        \
+    ASSERT(name##_cb_calls[0] == 1);                                          \
+    ASSERT(name##_cb_calls[1] == 0);                                          \
+    ASSERT(name##_cb_calls[2] == 1);                                          \
+  } while (0)
+
+DEFINE_GLOBALS_AND_CBS(idle)
+DEFINE_GLOBALS_AND_CBS(prepare)
+DEFINE_GLOBALS_AND_CBS(check)
+
+
+TEST_IMPL(queue_foreach_delete) {
+  uv_loop_t* loop;
+  int r;
+
+  loop = uv_default_loop();
+
+  INIT_AND_START(idle,    loop);
+  INIT_AND_START(prepare, loop);
+  INIT_AND_START(check,   loop);
+
+  r = uv_run(loop, UV_RUN_NOWAIT);
+  ASSERT(r == 1);
+
+  END_ASSERTS(idle);
+  END_ASSERTS(prepare);
+  END_ASSERTS(check);
+
+  MAKE_VALGRIND_HAPPY();
+
+  return 0;
+}

uv.gyp

@@ -347,6 +347,7 @@
         'test/test-poll-close-doesnt-corrupt-stack.c',
         'test/test-poll-closesocket.c',
         'test/test-process-title.c',
+        'test/test-queue-foreach-delete.c',
         'test/test-ref.c',
         'test/test-run-nowait.c',
         'test/test-run-once.c',