{"id":10417,"url":"https://patchwork.libcamera.org/api/patches/10417/?format=json","web_url":"https://patchwork.libcamera.org/patch/10417/","project":{"id":1,"url":"https://patchwork.libcamera.org/api/projects/1/?format=json","name":"libcamera","link_name":"libcamera","list_id":"libcamera_core","list_email":"libcamera-devel@lists.libcamera.org","web_url":"","scm_url":"","webscm_url":""},"msgid":"<20201113063815.10288-3-laurent.pinchart@ideasonboard.com>","date":"2020-11-13T06:38:12","name":"[libcamera-devel,v1,2/5] cam: Use libevent to implement event loop","commit_ref":null,"pull_url":null,"state":"accepted","archived":false,"hash":"162d42d455d063148b2c68621ebf638dbb754c4a","submitter":{"id":2,"url":"https://patchwork.libcamera.org/api/people/2/?format=json","name":"Laurent Pinchart","email":"laurent.pinchart@ideasonboard.com"},"delegate":null,"mbox":"https://patchwork.libcamera.org/patch/10417/mbox/","series":[{"id":1458,"url":"https://patchwork.libcamera.org/api/series/1458/?format=json","web_url":"https://patchwork.libcamera.org/project/libcamera/list/?series=1458","date":"2020-11-13T06:38:10","name":"cam: Move request processing to main thread","version":1,"mbox":"https://patchwork.libcamera.org/series/1458/mbox/"}],"comments":"https://patchwork.libcamera.org/api/patches/10417/comments/","check":"pending","checks":"https://patchwork.libcamera.org/api/patches/10417/checks/","tags":{},"headers":{"Return-Path":"","X-Original-To":"parsemail@patchwork.libcamera.org","Delivered-To":"parsemail@patchwork.libcamera.org","Received":["from lancelot.ideasonboard.com (lancelot.ideasonboard.com\n\t[92.243.16.209])\n\tby patchwork.libcamera.org (Postfix) with ESMTPS id 01CBDBE086\n\tfor ;\n\tFri, 13 Nov 2020 06:38:27 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 30015631C4;\n\tFri, 13 Nov 2020 07:38:26 +0100 (CET)","from perceval.ideasonboard.com (perceval.ideasonboard.com\n\t[213.167.242.64])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id A91D7631AF\n\tfor ;\n\tFri, 13 Nov 2020 07:38:24 +0100 (CET)","from pendragon.lan (62-78-145-57.bb.dnainternet.fi [62.78.145.57])\n\tby perceval.ideasonboard.com (Postfix) with ESMTPSA id 45ADFA1B\n\tfor ;\n\tFri, 13 Nov 2020 07:38:24 +0100 (CET)"],"Authentication-Results":"lancelot.ideasonboard.com;\n\tdkim=fail reason=\"signature verification failed\" (1024-bit key;\n\tunprotected) header.d=ideasonboard.com header.i=@ideasonboard.com\n\theader.b=\"vzyN5uxk\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com;\n\ts=mail; t=1605249504;\n\tbh=14Ycuh7MxS3qAE+FZCnYtm0w6OPq3HBKUDkkJNWhlPo=;\n\th=From:To:Subject:Date:In-Reply-To:References:From;\n\tb=vzyN5uxkfNCT/HSONJUCfvOro9GK8TRtVVEr2QFinZghLodp7Exh53YJ+pqabWMYB\n\ti4GzCV1pW467sIAgU2ZYS9QL0s0CCMHazOJWe+C0qFCEvugJeZ80YxluZNPJgHISF2\n\tcEK9sJDoPWRNQAt7YFPIu40GlKj97lqqmFWPxPHw=","From":"Laurent Pinchart ","To":"libcamera-devel@lists.libcamera.org","Date":"Fri, 13 Nov 2020 08:38:12 +0200","Message-Id":"<20201113063815.10288-3-laurent.pinchart@ideasonboard.com>","X-Mailer":"git-send-email 2.27.0","In-Reply-To":"<20201113063815.10288-1-laurent.pinchart@ideasonboard.com>","References":"<20201113063815.10288-1-laurent.pinchart@ideasonboard.com>","MIME-Version":"1.0","Subject":"[libcamera-devel] [PATCH v1 2/5] cam: Use libevent to implement\n\tevent loop","X-BeenThere":"libcamera-devel@lists.libcamera.org","X-Mailman-Version":"2.1.29","Precedence":"list","List-Id":"","List-Unsubscribe":",\n\t","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n\t","Content-Type":"text/plain; charset=\"us-ascii\"","Content-Transfer-Encoding":"7bit","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "},"content":"To prepare for removal of the EventDispatcher from the libcamera public\nAPI, switch to libevent to handle the event loop.\n\nSigned-off-by: Laurent Pinchart \n---\n src/cam/event_loop.cpp | 34 +++++++++++++++++++++++++++-------\n src/cam/event_loop.h | 15 ++++++++-------\n src/cam/main.cpp | 16 +++++-----------\n src/cam/meson.build | 13 ++++++++++++-\n 4 files changed, 52 insertions(+), 26 deletions(-)","diff":"diff --git a/src/cam/event_loop.cpp b/src/cam/event_loop.cpp\nindex e8ab861790ed..13f2583da0a1 100644\n--- a/src/cam/event_loop.cpp\n+++ b/src/cam/event_loop.cpp\n@@ -5,19 +5,34 @@\n * event_loop.cpp - cam - Event loop\n */\n \n-#include \n-\n #include \"event_loop.h\"\n \n-using namespace libcamera;\n+#include \n+#include \n+#include \n \n-EventLoop::EventLoop(EventDispatcher *dispatcher)\n-\t: dispatcher_(dispatcher)\n+EventLoop *EventLoop::instance_ = nullptr;\n+\n+EventLoop::EventLoop()\n {\n+\tassert(!instance_);\n+\n+\tevthread_use_pthreads();\n+\tevent_ = event_base_new();\n+\tinstance_ = this;\n }\n \n EventLoop::~EventLoop()\n {\n+\tinstance_ = nullptr;\n+\n+\tevent_base_free(event_);\n+\tlibevent_global_shutdown();\n+}\n+\n+EventLoop *EventLoop::instance()\n+{\n+\treturn instance_;\n }\n \n int EventLoop::exec()\n@@ -26,7 +41,7 @@ int EventLoop::exec()\n \texit_.store(false, std::memory_order_release);\n \n \twhile (!exit_.load(std::memory_order_acquire))\n-\t\tdispatcher_->processEvents();\n+\t\tevent_base_loop(event_, EVLOOP_NO_EXIT_ON_EMPTY);\n \n \treturn exitCode_;\n }\n@@ -35,5 +50,10 @@ void EventLoop::exit(int code)\n {\n \texitCode_ = code;\n \texit_.store(true, std::memory_order_release);\n-\tdispatcher_->interrupt();\n+\tinterrupt();\n+}\n+\n+void EventLoop::interrupt()\n+{\n+\tevent_base_loopbreak(event_);\n }\ndiff --git a/src/cam/event_loop.h b/src/cam/event_loop.h\nindex 581c7cba2fc4..b1c6bd103080 100644\n--- a/src/cam/event_loop.h\n+++ b/src/cam/event_loop.h\n@@ -9,26 +9,27 @@\n \n #include \n \n-#include \n-\n-namespace libcamera {\n-class EventDispatcher;\n-}\n+struct event_base;\n \n class EventLoop\n {\n public:\n-\tEventLoop(libcamera::EventDispatcher *dispatcher);\n+\tEventLoop();\n \t~EventLoop();\n \n+\tstatic EventLoop *instance();\n+\n \tint exec();\n \tvoid exit(int code = 0);\n \n private:\n-\tlibcamera::EventDispatcher *dispatcher_;\n+\tstatic EventLoop *instance_;\n \n+\tstruct event_base *event_;\n \tstd::atomic exit_;\n \tint exitCode_;\n+\n+\tvoid interrupt();\n };\n \n #endif /* __CAM_EVENT_LOOP_H__ */\ndiff --git a/src/cam/main.cpp b/src/cam/main.cpp\nindex b3a8d94f5739..e01be63a7058 100644\n--- a/src/cam/main.cpp\n+++ b/src/cam/main.cpp\n@@ -52,7 +52,7 @@ private:\n \tCameraManager *cm_;\n \tstd::shared_ptr camera_;\n \tstd::unique_ptr config_;\n-\tEventLoop *loop_;\n+\tEventLoop loop_;\n \n \tbool strictFormats_;\n };\n@@ -60,7 +60,7 @@ private:\n CamApp *CamApp::app_ = nullptr;\n \n CamApp::CamApp()\n-\t: cm_(nullptr), camera_(nullptr), config_(nullptr), loop_(nullptr),\n+\t: cm_(nullptr), camera_(nullptr), config_(nullptr),\n \t strictFormats_(false)\n {\n \tCamApp::app_ = this;\n@@ -134,16 +134,11 @@ int CamApp::init(int argc, char **argv)\n \t\tstd::cout << \"Monitoring new hotplug and unplug events\" << std::endl;\n \t}\n \n-\tloop_ = new EventLoop(cm_->eventDispatcher());\n-\n \treturn 0;\n }\n \n void CamApp::cleanup()\n {\n-\tdelete loop_;\n-\tloop_ = nullptr;\n-\n \tif (camera_) {\n \t\tcamera_->release();\n \t\tcamera_.reset();\n@@ -166,8 +161,7 @@ int CamApp::exec()\n \n void CamApp::quit()\n {\n-\tif (loop_)\n-\t\tloop_->exit();\n+\tloop_.exit();\n }\n \n int CamApp::parseOptions(int argc, char *argv[])\n@@ -366,13 +360,13 @@ int CamApp::run()\n \t}\n \n \tif (options_.isSet(OptCapture)) {\n-\t\tCapture capture(camera_, config_.get(), loop_);\n+\t\tCapture capture(camera_, config_.get(), &loop_);\n \t\treturn capture.run(options_);\n \t}\n \n \tif (options_.isSet(OptMonitor)) {\n \t\tstd::cout << \"Press Ctrl-C to interrupt\" << std::endl;\n-\t\tret = loop_->exec();\n+\t\tret = loop_.exec();\n \t\tif (ret)\n \t\t\tstd::cout << \"Failed to run monitor loop\" << std::endl;\n \t}\ndiff --git a/src/cam/meson.build b/src/cam/meson.build\nindex 89e124fbae2a..62003c58dad0 100644\n--- a/src/cam/meson.build\n+++ b/src/cam/meson.build\n@@ -1,5 +1,12 @@\n # SPDX-License-Identifier: CC0-1.0\n \n+libevent = dependency('libevent_pthreads', required : false)\n+\n+if not libevent.found()\n+ warning('libevent_pthreads not found,\\'cam\\' application will not be compiled')\n+ subdir_done()\n+endif\n+\n cam_sources = files([\n 'buffer_writer.cpp',\n 'capture.cpp',\n@@ -10,5 +17,9 @@ cam_sources = files([\n ])\n \n cam = executable('cam', cam_sources,\n- dependencies : [ libatomic, libcamera_dep ],\n+ dependencies : [\n+ libatomic,\n+ libcamera_dep,\n+ libevent,\n+ ],\n install : true)\n","prefixes":["libcamera-devel","v1","2/5"]}