gcc/libgo/runtime/go-chan-len.c
Ian Lance Taylor 7a9389330e Add Go frontend, libgo library, and Go testsuite.
gcc/:
	* gcc.c (default_compilers): Add entry for ".go".
	* common.opt: Add -static-libgo as a driver option.
	* doc/install.texi (Configuration): Mention libgo as an option for
	--enable-shared.  Mention go as an option for --enable-languages.
	* doc/invoke.texi (Overall Options): Mention .go as a file name
	suffix.  Mention go as a -x option.
	* doc/frontends.texi (G++ and GCC): Mention Go as a supported
	language.
	* doc/sourcebuild.texi (Top Level): Mention libgo.
	* doc/standards.texi (Standards): Add section on Go language.
	Move references for other languages into their own section.
	* doc/contrib.texi (Contributors): Mention that I contributed the
	Go frontend.
gcc/testsuite/:
	* lib/go.exp: New file.
	* lib/go-dg.exp: New file.
	* lib/go-torture.exp: New file.
	* lib/target-supports.exp (check_compile): Match // Go.

From-SVN: r167407
2010-12-03 04:34:57 +00:00

42 lines
1006 B
C

/* go-chan-len.c -- the len function applied to a channel.
Copyright 2009 The Go Authors. All rights reserved.
Use of this source code is governed by a BSD-style
license that can be found in the LICENSE file. */
#include <stddef.h>
#include "go-assert.h"
#include "channel.h"
/* Return the len function applied to a channel--the number of
elements in the buffer. This could be done inline but I'm doing it
as a function for now to make it easy to change the channel
structure. */
size_t
__go_chan_len (struct __go_channel *channel)
{
int i;
size_t ret;
if (channel == NULL)
return 0;
i = pthread_mutex_lock (&channel->lock);
__go_assert (i == 0);
if (channel->num_entries == 0)
ret = 0;
else if (channel->next_fetch == channel->next_store)
ret = 0;
else
ret = ((channel->next_store + channel->num_entries - channel->next_fetch)
% channel->num_entries);
i = pthread_mutex_unlock (&channel->lock);
__go_assert (i == 0);
return ret;
}