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authorEric Wong <e@80x24.org>2019-12-20 01:39:13 +0000
committerEric Wong <e@80x24.org>2020-01-06 08:15:12 +0000
commit044d1e1777f37a77084794fadce86b4865a1ccfc (patch)
tree82b6eead3126f6c214d05ba24c54a1492f294dd4 /lib/dtas/pipe.rb
parentc33e1719414b5de309c7cd45af404b94d8517fc7 (diff)
downloaddtas-044d1e1777f37a77084794fadce86b4865a1ccfc.tar.gz
The values of F_{GET,SET}PIPE_SZ are architecture-independent
and stable in Linux (unlike Ruby :P), so we won't need to bother
loading an extra .so here for two constants.
Diffstat (limited to 'lib/dtas/pipe.rb')
-rw-r--r--lib/dtas/pipe.rb20
1 files changed, 12 insertions, 8 deletions
diff --git a/lib/dtas/pipe.rb b/lib/dtas/pipe.rb
index 58d926c..4c3203d 100644
--- a/lib/dtas/pipe.rb
+++ b/lib/dtas/pipe.rb
@@ -1,10 +1,6 @@
 # Copyright (C) 2013-2019 all contributors <dtas-all@nongnu.org>
 # License: GPL-3.0+ <https://www.gnu.org/licenses/gpl-3.0.txt>
 # frozen_string_literal: true
-begin
-  require 'sleepy_penguin'
-rescue LoadError
-end
 require_relative '../dtas'
 require_relative 'writable_iter'
 require_relative 'nonblock'
@@ -14,6 +10,11 @@ class DTAS::Pipe < DTAS::Nonblock # :nodoc:
   include DTAS::WritableIter
   attr_accessor :sink
 
+  if RUBY_PLATFORM =~ /linux/i && File.readable?('/proc/sys/fs/pipe-max-size')
+    F_SETPIPE_SZ = 1031
+    F_GETPIPE_SZ = 1032
+  end
+
   def self.new
     _, w = rv = pipe
     w.writable_iter_init
@@ -21,13 +22,16 @@ class DTAS::Pipe < DTAS::Nonblock # :nodoc:
   end
 
   def pipe_size=(nr)
-    defined?(SleepyPenguin::F_SETPIPE_SZ) and
-      fcntl(SleepyPenguin::F_SETPIPE_SZ, nr)
+    fcntl(F_SETPIPE_SZ, nr) if defined?(F_SETPIPE_SZ)
+  rescue Errno::EINVAL # old kernel
+  rescue Errno::EPERM
+    # resizes fail if Linux is close to the pipe limit for the user
+    # or if the user does not have permissions to resize
   end
 
   def pipe_size
-    fcntl(SleepyPenguin::F_GETPIPE_SZ)
-  end if defined?(SleepyPenguin::F_GETPIPE_SZ)
+    fcntl(F_GETPIPE_SZ)
+  end if defined?(F_GETPIPE_SZ)
 
   # avoid syscall, we never change IO#nonblock= directly
   def nonblock?