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[79.124.17.100]) by mx.google.com with ESMTP id a2si15820973wmc.73.2017.03.06.11.54.18; Mon, 06 Mar 2017 11:54:19 -0800 (PST) Received-SPF: pass (google.com: domain of ffmpeg-devel-bounces@ffmpeg.org designates 79.124.17.100 as permitted sender) client-ip=79.124.17.100; Authentication-Results: mx.google.com; dkim=neutral (body hash did not verify) header.i=@gmail.com; spf=pass (google.com: domain of ffmpeg-devel-bounces@ffmpeg.org designates 79.124.17.100 as permitted sender) smtp.mailfrom=ffmpeg-devel-bounces@ffmpeg.org; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=gmail.com Received: from [127.0.1.1] (localhost [127.0.0.1]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTP id 088D9680A4D; Mon, 6 Mar 2017 21:54:03 +0200 (EET) X-Original-To: ffmpeg-devel@ffmpeg.org Delivered-To: ffmpeg-devel@ffmpeg.org Received: from mail-pg0-f67.google.com (mail-pg0-f67.google.com [74.125.83.67]) by ffbox0-bg.mplayerhq.hu (Postfix) with ESMTPS id 6098D6809AC for ; Mon, 6 Mar 2017 21:53:55 +0200 (EET) Received: by mail-pg0-f67.google.com with SMTP id 25so20643826pgy.3 for ; Mon, 06 Mar 2017 11:54:08 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=hGfhqHRnLWZ+U674wzgQdTBXRykjykPp24miORrePJY=; b=jM1VAzBqB6+gcGj7kVQbWvjW99FZECbOEQezPnsIX+JWvVCE8O9M2Ednx+MjvgUZXk 5rT/Cz5J6V3C3fz9ableAhCpSJBKhxf+MxshMHKjwAiqYHycTGebzAGY3RpQzeXNuG7z DDSags7a2a2omN33Cw/2psVMKg3yRWqh5uDsgDRWoNV5grIYcJV1oWdnNeTlt6LWK6Xt x90A6dRED6l2Cxzn2RGQiXUYzZVitvwQk6qVP6YfmakwbGBIJy/vnZb/NuRVpI7Jb2tV biAFnxKcLjpgAeLlSXJ/g/uADQN5HqoHDHKEgAaHr2cqR6UGl5VkzVgRd5eEUTAZUZyO OFyw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=hGfhqHRnLWZ+U674wzgQdTBXRykjykPp24miORrePJY=; b=ZN68I0rvYOop/Wp8JKKbk8sHd5/T3MjjpeRMRkmntJsB2yfJ522ACdC2jM3zGv4fmQ HT1oOS8JYW56gqz0LvQauEgXp8WdE6OSz3aa3D6ijabsr/6FfdOh1xRqgDlm5nKDXoDB 2VkBioZ/CN7UuOhWXrwekFeRbFr+cqaPntpWjIeZgdfJrijrcXYDkVENJEjHCwFHlJbX D9hmGEQbe1hGZuvPB87b/UAD/foejgWlxRAn2evRTJGl1ZaaFnt3JNCTG3H4rVtnTeDk VaZVVsJLAsVBARZiSJz6qCAYq9El8uthK98SY6F/HOyt7/1N+FzDKK01jiZXwgLw+NsV Zsig== X-Gm-Message-State: AMke39kNCn3qBY2Cn6vLvbUm8d9IKTvhq01/a8mkONsTRt6zH+OboxK6GkbPoKMD9X79ow== X-Received: by 10.99.119.196 with SMTP id s187mr22318318pgc.225.1488829690791; Mon, 06 Mar 2017 11:48:10 -0800 (PST) Received: from localhost.localdomain ([114.120.237.152]) by smtp.gmail.com with ESMTPSA id p4sm41362446pgd.50.2017.03.06.11.48.09 (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 06 Mar 2017 11:48:10 -0800 (PST) From: Muhammad Faiz To: ffmpeg-devel@ffmpeg.org Date: Tue, 7 Mar 2017 02:47:39 +0700 Message-Id: <20170306194739.1870-4-mfcc64@gmail.com> X-Mailer: git-send-email 2.9.3 In-Reply-To: <20170306194739.1870-1-mfcc64@gmail.com> References: <20170306194739.1870-1-mfcc64@gmail.com> Subject: [FFmpeg-devel] [PATCH 4/4] avdevice/alldevice: make avdevice_register_all thread safe X-BeenThere: ffmpeg-devel@ffmpeg.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: FFmpeg development discussions and patches List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: FFmpeg development discussions and patches Cc: Muhammad Faiz MIME-Version: 1.0 Errors-To: ffmpeg-devel-bounces@ffmpeg.org Sender: "ffmpeg-devel" Signed-off-by: Muhammad Faiz --- libavdevice/alldevices.c | 13 ++++++++++--- libavdevice/avdevice.h | 1 - 2 files changed, 10 insertions(+), 4 deletions(-) diff --git a/libavdevice/alldevices.c b/libavdevice/alldevices.c index a761be4..cc8b8ce 100644 --- a/libavdevice/alldevices.c +++ b/libavdevice/alldevices.c @@ -18,6 +18,8 @@ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ +#include + #include "config.h" #include "avdevice.h" @@ -39,11 +41,14 @@ void avdevice_register_all(void) { - static int initialized; + static atomic_int initialized; + static atomic_int ready; - if (initialized) + if (atomic_exchange_explicit(&initialized, 1, memory_order_relaxed)) { + while (!atomic_load_explicit(&ready, memory_order_relaxed)) + ; return; - initialized = 1; + } /* devices */ REGISTER_INOUTDEV(ALSA, alsa); @@ -75,4 +80,6 @@ void avdevice_register_all(void) /* external libraries */ REGISTER_INDEV (LIBCDIO, libcdio); REGISTER_INDEV (LIBDC1394, libdc1394); + + atomic_store_explicit(&ready, 1, memory_order_relaxed); } diff --git a/libavdevice/avdevice.h b/libavdevice/avdevice.h index 6153f2c..84f374a 100644 --- a/libavdevice/avdevice.h +++ b/libavdevice/avdevice.h @@ -67,7 +67,6 @@ const char *avdevice_license(void); /** * Initialize libavdevice and register all the input and output devices. - * @warning This function is not thread safe. */ void avdevice_register_all(void);