Add rb_io_open_descriptor function

CHANGELOG.md

@@ -28,6 +28,7 @@ Compatibility:
 * Implement `rb_str_format()` (#3716, @andrykonchin).
 * Add `IO#{pread, pwrite}` methods (#3718, @andrykonchin).
 * Add `rb_io_closed_p()` (#3681, @andrykonchin).
+* Add `rb_io_open_descriptor()` (#3681, @andrykonchin).
 
 Performance:
 

lib/cext/include/truffleruby/truffleruby-abi-version.h

@@ -20,6 +20,6 @@
 // $RUBY_VERSION must be the same as TruffleRuby.LANGUAGE_VERSION.
 // $ABI_NUMBER starts at 1 and is incremented for every ABI-incompatible change.
 
-#define TRUFFLERUBY_ABI_VERSION "3.3.5.5"
+#define TRUFFLERUBY_ABI_VERSION "3.3.5.6"
 
 #endif

lib/truffle/truffle/cext.rb

@@ -2367,6 +2367,16 @@ def rb_io_path(io)
     io.instance_variable_get(:@path)
   end
 
+  def rb_io_open_descriptor(klass, fd, mode, path, timeout, internal_encoding, external_encoding, flags, options)
+    return klass.allocate if klass != IO and klass != File
+
+    # Translate Ruby-specific modes (`FMODE_`) to corresponding platform-specific file open flags (`O_`).
+    # Ruby interface accepts `FMODE_` flags, but C API functions accept `O_` flags.
+    mode = Truffle::IOOperations.translate_omode_to_fmode(mode)
+
+    klass.new(fd, mode, **options, internal_encoding: internal_encoding, external_encoding: external_encoding, path: path, flags: flags, skip_mode_enforcing: true)
+  end
+
   def rb_io_closed_p(io)
     io.closed?
   end

spec/ruby/optional/capi/ext/io_spec.c

@@ -375,6 +375,23 @@ static VALUE io_spec_rb_io_path(VALUE self, VALUE io) {
 static VALUE io_spec_rb_io_closed_p(VALUE self, VALUE io) {
   return rb_io_closed_p(io);
 }
+
+static VALUE io_spec_rb_io_open_descriptor(VALUE self, VALUE klass, VALUE descriptor, VALUE mode, VALUE path, VALUE timeout, VALUE internal_encoding, VALUE external_encoding, VALUE ecflags, VALUE ecopts) {
+  struct rb_io_encoding *io_encoding;
+
+  io_encoding = (struct rb_io_encoding *) malloc(sizeof(struct rb_io_encoding));
+
+  io_encoding->enc = rb_to_encoding(internal_encoding);
+  io_encoding->enc2 = rb_to_encoding(external_encoding);
+  io_encoding->ecflags = FIX2INT(ecflags);
+  io_encoding->ecopts = ecopts;
+
+  return rb_io_open_descriptor(klass, FIX2INT(descriptor), FIX2INT(mode), path, timeout, io_encoding);
+}
+
+static VALUE io_spec_rb_io_open_descriptor_without_encoding(VALUE self, VALUE klass, VALUE descriptor, VALUE mode, VALUE path, VALUE timeout) {
+  return rb_io_open_descriptor(klass, FIX2INT(descriptor), FIX2INT(mode), path, timeout, NULL);
+}
 #endif
 
 void Init_io_spec(void) {
@@ -414,6 +431,13 @@ void Init_io_spec(void) {
   rb_define_method(cls, "rb_io_mode", io_spec_rb_io_mode, 1);
   rb_define_method(cls, "rb_io_path", io_spec_rb_io_path, 1);
   rb_define_method(cls, "rb_io_closed_p", io_spec_rb_io_closed_p, 1);
+  rb_define_method(cls, "rb_io_open_descriptor", io_spec_rb_io_open_descriptor, 9);
+  rb_define_method(cls, "rb_io_open_descriptor_without_encoding", io_spec_rb_io_open_descriptor_without_encoding, 5);
+  rb_define_const(cls, "FMODE_READABLE", INT2FIX(FMODE_READABLE));
+  rb_define_const(cls, "FMODE_WRITABLE", INT2FIX(FMODE_WRITABLE));
+  rb_define_const(cls, "FMODE_BINMODE", INT2FIX(FMODE_BINMODE));
+  rb_define_const(cls, "FMODE_TEXTMODE", INT2FIX(FMODE_TEXTMODE));
+  rb_define_const(cls, "ECONV_UNIVERSAL_NEWLINE_DECORATOR", INT2FIX(ECONV_UNIVERSAL_NEWLINE_DECORATOR));
 #endif
 }
 

spec/ruby/optional/capi/io_spec.rb

@@ -530,6 +530,126 @@
         @r_io.closed?.should == true
       end
     end
+
+    describe "rb_io_open_descriptor" do
+      it "creates a new IO instance" do
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.should.is_a?(IO)
+      end
+
+      it "return an instance of the specified class" do
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.class.should == File
+
+        io = @o.rb_io_open_descriptor(IO, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.class.should == IO
+      end
+
+      it "sets the specified file descriptor" do
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.fileno.should == @r_io.fileno
+      end
+
+      it "sets the specified path" do
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.path.should == "a.txt"
+      end
+
+      it "sets the specified mode" do
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, CApiIOSpecs::FMODE_BINMODE, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.should.binmode?
+
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, CApiIOSpecs::FMODE_TEXTMODE, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.should_not.binmode?
+      end
+
+      it "sets the specified timeout" do
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.timeout.should == 60
+      end
+
+      it "sets the specified internal encoding" do
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.internal_encoding.should == Encoding::US_ASCII
+      end
+
+      it "sets the specified external encoding" do
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.external_encoding.should == Encoding::UTF_8
+      end
+
+      it "does not apply the specified encoding flags" do
+        File.write("a.txt", "123\r\n456\n89")
+        file = File.open("a.txt", "r")
+
+        io = @o.rb_io_open_descriptor(File, file.fileno, CApiIOSpecs::FMODE_READABLE, "a.txt", 60, "US-ASCII", "UTF-8", CApiIOSpecs::ECONV_UNIVERSAL_NEWLINE_DECORATOR, {})
+        io.read_nonblock(20).should == "123\r\n456\n89"
+      end
+
+      it "ignores the IO open options" do
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {external_encoding: "windows-1251"})
+        io.external_encoding.should == Encoding::UTF_8
+
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {internal_encoding: "windows-1251"})
+        io.internal_encoding.should == Encoding::US_ASCII
+
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {encoding: "windows-1251:binary"})
+        io.external_encoding.should == Encoding::UTF_8
+        io.internal_encoding.should == Encoding::US_ASCII
+
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {textmode: false})
+        io.should_not.binmode?
+
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {binmode: true})
+        io.should_not.binmode?
+
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {autoclose: false})
+        io.should.autoclose?
+
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, "a.txt", 60, "US-ASCII", "UTF-8", 0, {path: "a.txt"})
+        io.path.should == "a.txt"
+      end
+
+      it "ignores the IO encoding options" do
+        io = @o.rb_io_open_descriptor(File, @w_io.fileno, CApiIOSpecs::FMODE_WRITABLE, "a.txt", 60, "US-ASCII", "UTF-8", 0, {crlf_newline: true})
+
+        io.write("123\r\n456\n89")
+        io.flush
+
+        @r_io.read_nonblock(20).should == "123\r\n456\n89"
+      end
+
+      it "allows wrong mode" do
+        io = @o.rb_io_open_descriptor(File, @w_io.fileno, CApiIOSpecs::FMODE_READABLE, "a.txt", 60, "US-ASCII", "UTF-8", 0, {})
+        io.should.is_a?(File)
+
+        -> { io.read_nonblock(1) }.should raise_error(Errno::EBADF)
+      end
+
+      it "tolerates NULL as rb_io_encoding *encoding parameter" do
+        io = @o.rb_io_open_descriptor_without_encoding(File, @r_io.fileno, 0, "a.txt", 60)
+        io.should.is_a?(File)
+      end
+
+      it "deduplicates path String" do
+        path = "a.txt".dup
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, path, 60, "US-ASCII", "UTF-8", 0, {})
+        io.path.should_not equal(path)
+
+        path = "a.txt".freeze
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, path, 60, "US-ASCII", "UTF-8", 0, {})
+        io.path.should_not equal(path)
+      end
+
+      it "calls #to_str to convert a path to a String" do
+        path = Object.new
+        def path.to_str; "a.txt"; end
+
+        io = @o.rb_io_open_descriptor(File, @r_io.fileno, 0, path, 60, "US-ASCII", "UTF-8", 0, {})
+
+        io.path.should == "a.txt"
+      end
+    end
   end
 
   ruby_version_is "3.4" do

spec/tags/optional/capi/io_tags.txt

@@ -1,3 +1,5 @@
 fails:C-API IO function rb_io_maybe_wait_writable raises an IOError if the IO is not initialized
 fails:C-API IO function rb_io_maybe_wait_readable raises an IOError if the IO is not initialized
 fails:C-API IO function rb_io_maybe_wait raises an IOError if the IO is not initialized
+fails:C-API IO function rb_io_open_descriptor sets the specified timeout
+fails:C-API IO function rb_io_open_descriptor ignores the IO open options

src/main/c/cext/io.c

@@ -43,6 +43,33 @@ VALUE rb_io_path(VALUE io) {
   return RUBY_CEXT_INVOKE("rb_io_path", io);
 }
 
+VALUE rb_io_open_descriptor(VALUE klass, int descriptor, int mode, VALUE path, VALUE timeout, struct rb_io_encoding *encoding) {
+  VALUE internal_encoding, external_encoding, ecflags, ecopts;
+
+  if (encoding) {
+    internal_encoding = rb_enc_from_encoding(encoding->enc);
+    external_encoding = rb_enc_from_encoding(encoding->enc2);
+    ecflags = INT2FIX(encoding->ecflags);
+    ecopts = encoding->ecopts;
+  } else {
+    internal_encoding = Qnil;
+    external_encoding = Qnil;
+    ecflags = INT2FIX(0);
+    ecopts = rb_hash_new();
+  }
+
+  return RUBY_CEXT_INVOKE("rb_io_open_descriptor",
+    klass,
+    INT2FIX(descriptor),
+    INT2FIX(mode),
+    path,
+    timeout,
+    internal_encoding,
+    external_encoding,
+    ecflags,
+    ecopts);
+}
+
 VALUE rb_io_closed_p(VALUE io) {
   return RUBY_CEXT_INVOKE("rb_io_closed_p", io);
 }

src/main/ruby/truffleruby/core/io.rb

@@ -817,7 +817,9 @@ def self.sysopen(path, mode = nil, perm = nil)
   #
   # The +sync+ attribute will also be set.
   #
-  def self.setup(io, fd, mode, sync)
+  # The +skip_mode_enforcing+ parameter is needed for implementing some C-functions and allows
+  # to bypass enforcing a specified file mode to be the same as current mode of a file.
+  def self.setup(io, fd, mode, sync, skip_mode_enforcing = false)
     if !Truffle::Boot.preinitializing? && Truffle::POSIX::NATIVE
       cur_mode = Truffle::POSIX.fcntl(fd, F_GETFL, 0)
       Errno.handle if cur_mode < 0
@@ -828,7 +830,7 @@ def self.setup(io, fd, mode, sync)
       mode = Truffle::IOOperations.parse_mode(mode)
       mode &= ACCMODE
 
-      if cur_mode and (cur_mode == RDONLY or cur_mode == WRONLY) and mode != cur_mode
+      if cur_mode and (cur_mode == RDONLY or cur_mode == WRONLY) and mode != cur_mode && !skip_mode_enforcing
         raise Errno::EINVAL, "Invalid mode #{cur_mode} for existing descriptor #{fd} (expected #{mode})"
       end
     else
@@ -863,7 +865,7 @@ def initialize(fd, mode = nil, **options)
 
     fd = Truffle::Type.coerce_to(fd, Integer, :to_int)
     sync = fd == 2 # stderr is always unbuffered, see setvbuf(3)
-    IO.setup(self, fd, mode, sync)
+    IO.setup(self, fd, mode, sync, options[:skip_mode_enforcing]) # :skip_mode_enforcing is a TruffleRuby specific option used internally only
 
     binmode if binary
     set_encoding external, internal