This module was introduced in 2015 for internal use within this library.
Neither of the two constants in it is used anymore. I don't think we
will be adding a new constant in the foreseeable future, either.
OPENSSL_NO_SOCK is unused since commit 998d66712a (r55191).
HAVE_TLSEXT_HOST_NAME is unused since commit 4eb4b3297a.
eed3894bda
As noted in commit a2ed156cc9 ("test/test_ssl: do not run NPN tests
for LibreSSL >= 2.6.1", 2017-08-13), NPN is known not to work properly
on LibreSSL.
Disable NPN support on LibreSSL, whether OPENSSL_NO_NEXTPROTONEG is
defined or not.
NPN is less relevant today anyway. Let's also silence test suite when
it's not available.
289f6e0e1f
When an object becomes "too complex" (in other words it has too many
variations in the shape tree), we transition it to use a "too complex"
shape and use a hash for storing instance variables.
Without this patch, there were rare cases where shape tree growth could
"explode" and cause performance degradation on what would otherwise have
been cached fast paths.
This patch puts a limit on shape tree growth, and gracefully degrades in
the rare case where there could be a factorial growth in the shape tree.
For example:
```ruby
class NG; end
HUGE_NUMBER.times do
NG.new.instance_variable_set(:"@unique_ivar_#{_1}", 1)
end
```
We consider objects to be "too complex" when the object's class has more
than SHAPE_MAX_VARIATIONS (currently 8) leaf nodes in the shape tree and
the object introduces a new variation (a new leaf node) associated with
that class.
For example, new variations on instances of the following class would be
considered "too complex" because those instances create more than 8
leaves in the shape tree:
```ruby
class Foo; end
9.times { Foo.new.instance_variable_set(":@uniq_#{_1}", 1) }
```
However, the following class is *not* too complex because it only has
one leaf in the shape tree:
```ruby
class Foo
def initialize
@a = @b = @c = @d = @e = @f = @g = @h = @i = nil
end
end
9.times { Foo.new }
``
This case is rare, so we don't expect this change to impact performance
of most applications, but it needs to be handled.
Co-Authored-By: Aaron Patterson <tenderlove@ruby-lang.org>
Count how many "variations" each class creates. A "variation" is a a
unique ordering of instance variables on a particular class. This can
also be thought of as a branch in the shape tree.
For example, the following Foo class will have 2 variations:
```ruby
class Foo ; end
Foo.new.instance_variable_set(:@a, 1) # case 1: creates one variation
Foo.new.instance_variable_set(:@b, 1) # case 2: creates another variation
foo = Foo.new
foo.instance_variable_set(:@a, 1) # does not create a new variation
foo.instance_variable_set(:@b, 1) # does not create a new variation (a continuation of the variation in case 1)
```
We will use this number to limit the amount of shapes that a class can
create and fallback to using a hash iv lookup.
Co-Authored-By: Aaron Patterson <tenderlove@ruby-lang.org>
LibreSSL 3.4 added EVP_DigestSign() and EVP_DigestVerify(). Use them
when available to prepare for the addition of Ed25519 support in
LibreSSL 3.7.
475b2bf766
