Backport #2560: IO.read not always closes the file

• Status: Closed
• Assignee: yugui (Yuki Sonoda)

[vvs (Vladimir Sizikov)]

=begin
Consider the following:

File.open('test_file', 'wb') { |f| f.write 'abc' }
IO.read('test_file', 0, -1) rescue nil
File.unlink('test_file')

On Windows the unlink call fails with:
`unlink': Permission denied - test_file (Errno::EACCES)

This is due to fact that IO.read, invoked with invalid offset parameter does not close the opened file. But the documentation clearly states that:
"read ensures the file is closed before returning."

This causes two RubySpec failures for IO.read:

mspec -t r core\io\read_spec.rb
ruby 1.9.2dev (2009-11-12 trunk 25723) [i386-mingw32]
..........E..E..................E.

An exception occurred during: after :each
IO.read raises an Errno::EINVAL when not passed a valid offset ERROR
Errno::EACCES: Permission denied - D:/work/jruby-dev/rubyspec.git/rubyspec_temp/io_read.txt
D:/work/jruby-dev/rubyspec.git/core/io/read_spec.rb:13:in block (2 levels) in <top (required)>' D:/work/jruby-dev/rubyspec.git/core/io/read_spec.rb:5:in <top (required)>'
D:/work/jruby-dev/mspec.git/bin/mspec-run:8:in `'

An exception occurred during: after :each
IO#read can be read from consecutively ERROR
Errno::EACCES: Permission denied - D:/work/jruby-dev/rubyspec.git/rubyspec_temp/io_read.txt
D:/work/jruby-dev/rubyspec.git/core/io/read_spec.rb:100:in block (2 levels) in <top (required)>' D:/work/jruby-dev/rubyspec.git/core/io/read_spec.rb:88:in <top (required)>'
D:/work/jruby-dev/mspec.git/bin/mspec-run:8:in `'
=end

[usa (Usaku NAKAMURA)]

=begin
Hello,

In message "[ruby-core:27429] [Bug #2560] IO.read not always closes the file"
on Jan.06,2010 02:31:39, [e-mail] wrote:

This is due to fact that IO.read, invoked with invalid offset parameter does not close the opened file. But the documentation clearly states that:
"read ensures the file is closed before returning."

1.8 has same problem, too.

This patch is for trunk.

Index: io.c

--- io.c (revision 26249)
+++ io.c (working copy)
@@ -7816,6 +7816,19 @@ io_s_read(struct foreach_arg *arg)
return io_read(arg->argc, arg->argv, arg->io);
}

+struct seek_arg {

• VALUE io;
• VALUE offset;
• int mode;
  +};

+static VALUE
+seek_before_read(struct seek_arg *arg)
+{

• rb_io_binmode(arg->io);
• return rb_io_seek(arg->io, arg->offset, arg->mode);
  +}

/*

• call-seq:

• IO.read(name, [length [, offset]] )   => string
  

@@ -7858,8 +7871,16 @@ rb_io_s_read(int argc, VALUE *argv, VALU
open_key_args(argc, argv, &arg);
if (NIL_P(arg.io)) return Qnil;
if (!NIL_P(offset)) {

• rb_io_binmode(arg.io);
• rb_io_seek(arg.io, offset, SEEK_SET);

• struct seek_arg sarg;
• int state = 0;
• sarg.io = arg.io;
• sarg.offset = offset;
• sarg.mode = SEEK_SET;
• rb_protect((VALUE (*)(VALUE))seek_before_read, (VALUE)&sarg, &state);
• if (state) {

•  rb_io_close(arg.io);
  

•  rb_jump_tag(state);
  

• }
  if (arg.argc == 2) arg.argc = 1;
  }
  return rb_ensure(io_s_read, (VALUE)&arg, rb_io_close, arg.io);
  
  Regards,
  --
  U.Nakamura [e-mail]

=end

[matz (Yukihiro Matsumoto)]

=begin
Hi,

In message "Re: [ruby-core:27483] Re: [Bug #2560] IO.read not always closes the file"
on Fri, 8 Jan 2010 14:29:53 +0900, "U.Nakamura" [e-mail] writes:

|In message "[ruby-core:27429] [Bug #2560] IO.read not always closes the file"
| on Jan.06,2010 02:31:39, [e-mail] wrote:
|> This is due to fact that IO.read, invoked with invalid offset parameter does not close the opened file. But the documentation clearly states that:
|> "read ensures the file is closed before returning."
|
|1.8 has same problem, too.
|
|This patch is for trunk.

Could you check in?

						matz.

=end

[usa (Usaku NAKAMURA)]

• Status changed from Open to Closed
• % Done changed from 0 to 100

=begin
This issue was solved with changeset r26250.
Vladimir, thank you for reporting this issue.
Your contribution to Ruby is greatly appreciated.
May Ruby be with you.

=end

[usa (Usaku NAKAMURA)]

• Status changed from Closed to Assigned
• Assignee set to yugui (Yuki Sonoda)

=begin

=end

[jeremyevans0 (Jeremy Evans)]

• Description updated (diff)
• Status changed from Assigned to Closed