From 17ed23bb6dfc942a8c51658b01135c3e2807ccf0 Mon Sep 17 00:00:00 2001
From: normal <normal@b2dd03c8-39d4-4d8f-98ff-823fe69b080e>
Date: Tue, 14 Aug 2018 17:07:36 +0000
Subject: [PATCH] spec/ruby/optional/capi/io_spec.rb: fix fragile spec from
 unpredictable errno

rb_io_wait_readable and rb_io_wait_writable depend on the TSD
errno value.  Due to the recent changes in r64352-r64353 to
restructure GVL, errno could be set to EAGAIN from the signal
self-pipe and cause the rb_io_wait_readable spec to block
unexpectedly.  This should fix rubyspec timeouts on Solaris:

  http://rubyci.s3.amazonaws.com/unstable11s/ruby-trunk/log/20180814T042506Z.fail.html.gz

* spec/ruby/optional/capi/ext/io_spec.c: add errno= setter method
* spec/ruby/optional/capi/io_spec.rb: set errno to appropriate values for tests

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@64359 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
---
 spec/ruby/optional/capi/ext/io_spec.c | 13 +++++++++++++
 spec/ruby/optional/capi/io_spec.rb    |  3 +++
 2 files changed, 16 insertions(+)

diff --git a/spec/ruby/optional/capi/ext/io_spec.c b/spec/ruby/optional/capi/ext/io_spec.c
index 40069bd54b..1b47830fa4 100644
--- a/spec/ruby/optional/capi/ext/io_spec.c
+++ b/spec/ruby/optional/capi/ext/io_spec.c
@@ -218,6 +218,17 @@ VALUE io_spec_rb_io_close(VALUE self, VALUE io) {
 }
 #endif
 
+/*
+ * this is needed to ensure rb_io_wait_*able functions behave
+ * predictably because errno may be set to unexpected values
+ * otherwise.
+ */
+static VALUE io_spec_errno_set(VALUE self, VALUE val) {
+  int e = NUM2INT(val);
+  errno = e;
+  return val;
+}
+
 void Init_io_spec(void) {
   VALUE cls = rb_define_class("CApiIOSpecs", rb_cObject);
 
@@ -296,6 +307,8 @@ void Init_io_spec(void) {
 #ifdef HAVE_RB_CLOEXEC_OPEN
   rb_define_method(cls, "rb_cloexec_open", io_spec_rb_cloexec_open, 3);
 #endif
+
+  rb_define_method(cls, "errno=", io_spec_errno_set, 1);
 }
 
 #ifdef __cplusplus
diff --git a/spec/ruby/optional/capi/io_spec.rb b/spec/ruby/optional/capi/io_spec.rb
index 466bfe5a41..a832c6a93b 100644
--- a/spec/ruby/optional/capi/io_spec.rb
+++ b/spec/ruby/optional/capi/io_spec.rb
@@ -236,6 +236,7 @@ describe "C-API IO function" do
 
   describe "rb_io_wait_writable" do
     it "returns false if there is no error condition" do
+      @o.errno = 0
       @o.rb_io_wait_writable(@w_io).should be_false
     end
 
@@ -254,6 +255,7 @@ describe "C-API IO function" do
   platform_is_not :windows do
     describe "rb_io_wait_readable" do
       it "returns false if there is no error condition" do
+        @o.errno = 0
         @o.rb_io_wait_readable(@r_io, false).should be_false
       end
 
@@ -271,6 +273,7 @@ describe "C-API IO function" do
           @w_io.write "rb_io_wait_readable"
         end
 
+        @o.errno = Errno::EAGAIN.new.errno
         @o.rb_io_wait_readable(@r_io, true).should be_true
         @o.instance_variable_get(:@read_data).should == "rb_io_wait_re"