[libvirt] [PATCHv2 1/2] build: avoid pthreads-win32 on mingw

[Eric Blake]

* src/util/threads.c (includes) [WIN32]: On mingw, favor native
threading over pthreads-win32 library.
* src/util/thread.h [WIN32] Likewise.
Suggested by Daniel P. Berrange.
---

Changes from v1: new patch:

On 06/03/2010 08:02 AM, Daniel P. Berrange wrote:
>>> So, is the libvirt patch worth installing, while we wait for the
>>> eventual fix of dependencies to not force mingw32-pthreads on 64-bit users?
>> 
>> How about changing configure.ac so that it defaults to looking for win32
>> threads on Win32, rather than trying pthreads
>That would also be a useful patch, but seems like it would be
>insufficient on its own.  In other words, there are two issues here -
>dealing with a broken <pthread.h> if it gets pulled in (which, for
>example, it WILL be pulled in by gnulib if it exists since it defines
>struct timespec, even if we don't use it for anything pthread-related),
>and the issue of whether we should favor pthread or win32 threading.

It turns out to not be a configure.ac issue at all.  I tested that
patch 1/2, in isolation, solves the struct timespec issue that I
was seeing on mingw by not pulling in pthreads-win32 code, but does
not solve remaining mingw issues.  And patch 2/2, in isolation,
compiles clean but doesn't avoid pthreads-win32.

So, okay to push both patches?

 src/util/threads-win32.c |    2 +-
 src/util/threads.c       |   12 ++++++------
 src/util/threads.h       |   10 ++++------
 3 files changed, 11 insertions(+), 13 deletions(-)

diff --git a/src/util/threads-win32.c b/src/util/threads-win32.c
index e478560..fe1fcd0 100644
--- a/src/util/threads-win32.c
+++ b/src/util/threads-win32.c
@@ -1,7 +1,7 @@
 /*
  * threads-win32.c: basic thread synchronization primitives
  *
- * Copyright (C) 2009 Red Hat, Inc.
+ * Copyright (C) 2009-2010 Red Hat, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
diff --git a/src/util/threads.c b/src/util/threads.c
index 8c0a91a..4ebce56 100644
--- a/src/util/threads.c
+++ b/src/util/threads.c
@@ -23,12 +23,12 @@

 #include "threads.h"

-#ifdef HAVE_PTHREAD_MUTEXATTR_INIT
+/* On mingw, we prefer native threading over the sometimes-broken
+ * pthreads-win32 library wrapper.  */
+#ifdef WIN32
+# include "threads-win32.c"
+#elif defined HAVE_PTHREAD_MUTEXATTR_INIT
 # include "threads-pthread.c"
 #else
-# ifdef WIN32
-#  include "threads-win32.c"
-# else
-#  error "Either pthreads or Win32 threads are required"
-# endif
+# error "Either pthreads or Win32 threads are required"
 #endif
diff --git a/src/util/threads.h b/src/util/threads.h
index 8b2be8d..db54ea0 100644
--- a/src/util/threads.h
+++ b/src/util/threads.h
@@ -61,14 +61,12 @@ int virThreadLocalInit(virThreadLocalPtr l,
 void *virThreadLocalGet(virThreadLocalPtr l);
 void virThreadLocalSet(virThreadLocalPtr l, void*);

-# ifdef HAVE_PTHREAD_MUTEXATTR_INIT
+# ifdef WIN32
+#  include "threads-win32.h"
+# elif defined HAVE_PTHREAD_MUTEXATTR_INIT
 #  include "threads-pthread.h"
 # else
-#  ifdef WIN32
-#   include "threads-win32.h"
-#  else
-#   error "Either pthreads or Win32 threads are required"
-#  endif
+#  error "Either pthreads or Win32 threads are required"
 # endif

 #endif
-- 
1.7.0.1