conf.c: use portable way to initialize recursive mutex

PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP is not in POSIX, as _NP
(non-portable) suggests.

exposing such a symbol in musl libc would lock in the ABI for all
times and makes it impossible to do future changes to the under-
lying struct without hideous symbol versioning hacks.

use the portable way instead: pthread_once was designed for such
cases.

Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Tested-by: John Spencer <maillist-alsa@barfooze.de>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>
This commit is contained in:
Timo Teräs 2013-11-08 13:17:58 +01:00 committed by Jaroslav Kysela
parent 7d06b3ed9f
commit ae035b7fe5

View file

@ -427,8 +427,8 @@ beginning:</P>
#ifndef DOC_HIDDEN
#ifdef HAVE_LIBPTHREAD
static pthread_mutex_t snd_config_update_mutex =
PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP;
static pthread_mutex_t snd_config_update_mutex;
static pthread_once_t snd_config_update_mutex_once = PTHREAD_ONCE_INIT;
#endif
struct _snd_config {
@ -472,8 +472,19 @@ typedef struct {
#ifdef HAVE_LIBPTHREAD
static void snd_config_init_mutex(void)
{
pthread_mutexattr_t attr;
pthread_mutexattr_init(&attr);
pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
pthread_mutex_init(&snd_config_update_mutex, &attr);
pthread_mutexattr_destroy(&attr);
}
static inline void snd_config_lock(void)
{
pthread_once(&snd_config_update_mutex_once, snd_config_init_mutex);
pthread_mutex_lock(&snd_config_update_mutex);
}