From patchwork Thu May 25 00:20:45 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Deborah Brouwer X-Patchwork-Id: 13254665 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 06461C77B7C for ; Thu, 25 May 2023 00:21:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232901AbjEYAVK (ORCPT ); Wed, 24 May 2023 20:21:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38404 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233082AbjEYAVJ (ORCPT ); Wed, 24 May 2023 20:21:09 -0400 Received: from madras.collabora.co.uk (madras.collabora.co.uk [IPv6:2a00:1098:0:82:1000:25:2eeb:e5ab]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1F647135 for ; Wed, 24 May 2023 17:21:06 -0700 (PDT) Received: from db550.. (node-1w7jr9st5p2esmclet71ntnwp.ipv6.telus.net [IPv6:2001:569:beb1:1500:6f9d:3a5c:4d25:e949]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256) (No client certificate requested) (Authenticated sender: dbrouwer) by madras.collabora.co.uk (Postfix) with ESMTPSA id 6280A66032CB; Thu, 25 May 2023 01:21:04 +0100 (BST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1684974065; bh=P106wTNuEibYz+U08z9gx85lbtcHdCymaEmO4toUxtk=; h=From:To:Cc:Subject:Date:From; b=jKkc58w7dx4VJCK+bTEQwBUx9lDn3pVYJsNBdX5FWtgmuuF2fnPx7H5Da5dwRhke9 8nyag0t4dMQGJQCVpjB/PHuXU0sj6rM7XMoLNtZ5T9po35WpQR3rtaJbltuHAlN6h5 XFb7Yf02MKxq2TT8x3kBFZcigRzO1OGgTohulYBk0O0nHfIj/qskqjTh4rePUz2eCS W3j/yserAq9R0zmMICSBlDp7OlL4C6tOJBKH7Pbqm4J+yZoKPZTxXI411LiKSO3yVI ZsXNV6eQDjsAtSm2mViJMw8UAg1dv8CxY3zKzzwqzAK1lRjdy5wXHc1WbT8zPzNwji 6ycALduOy2I2g== From: Deborah Brouwer To: linux-media@vger.kernel.org Cc: hverkuil-cisco@xs4all.nl, Nicolas Dufresne Subject: [PATCH] v4l2-tracer: Fix libv4l2tracer.so loader Date: Wed, 24 May 2023 17:20:45 -0700 Message-Id: <20230525002045.82937-1-deborah.brouwer@collabora.com> X-Mailer: git-send-email 2.40.1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org From: Nicolas Dufresne The code was still assuming libtools being use, so it didn't work installed anymore. Also, it didn't work installed if the full v4l2-tracer path was being passed. Fix this by always trying next by libv4l2tracer.so loading (using stat() to validate) and always fallback to the installed path otherwise. Signed-off-by: Nicolas Dufresne --- Hi - thanks to Nicolas for this patch. I tested tracing and retracing on both installed and uninstalled v4l2-tracer including with and without an absolute path and it all works as expected. Note that I've got three sets of v4l2-tracer patches outstanding now, but they all still apply independently of each other: Tuner patches: https://lore.kernel.org/linux-media/cover.1684453027.git.deborah.brouwer@collabora.com/ Debug patches: https://lore.kernel.org/linux-media/cover.1681245372.git.deborah.brouwer@collabora.com/ Thanks, Deb utils/v4l2-tracer/v4l2-tracer.cpp | 33 +++++++++++++++++-------------- 1 file changed, 18 insertions(+), 15 deletions(-) diff --git a/utils/v4l2-tracer/v4l2-tracer.cpp b/utils/v4l2-tracer/v4l2-tracer.cpp index e3f002a9..7c3662be 100644 --- a/utils/v4l2-tracer/v4l2-tracer.cpp +++ b/utils/v4l2-tracer/v4l2-tracer.cpp @@ -5,6 +5,7 @@ #include "retrace.h" #include +#include #include #include @@ -295,24 +296,26 @@ int tracer(int argc, char *argv[], bool retrace) fclose(trace_file); /* - * Preload the libv4l2tracer library. If the program is installed, load the library - * from its installed location, otherwise load it locally. If it's loaded locally, - * use ./configure --disable-dyn-libv4l. + * Preload the libv4l2tracer library. The libv4l2tracer is looked up next to + * the executable first in order to support uninstalled build. */ std::string libv4l2tracer_path; std::string program = argv[0]; - std::size_t idx = program.rfind("/v4l2-tracer"); - if (idx != std::string::npos) { - libv4l2tracer_path = program.replace(program.begin() + idx + 1, program.end(), ".libs"); - DIR *directory_pointer = opendir(libv4l2tracer_path.c_str()); - if (directory_pointer == nullptr) - libv4l2tracer_path = program.replace(program.begin() + idx, program.end(), "./.libs"); - else - closedir(directory_pointer); - } else { - libv4l2tracer_path = LIBTRACER_PATH; - } - libv4l2tracer_path += "/libv4l2tracer.so"; + std::size_t idx = program.rfind("/"); + struct stat sb; + + if (idx == std::string::npos) + idx = 0; + else + idx++; + + /* look for libv4l2tracer next to the executable */ + libv4l2tracer_path = program.replace(program.begin() + idx, program.end(), "libv4l2tracer.so"); + + /* otherwise, use the installation path */ + if (stat(libv4l2tracer_path.c_str(), &sb) == -1) + libv4l2tracer_path = std::string(LIBTRACER_PATH) + "/libv4l2tracer.so"; + if (is_verbose()) fprintf(stderr, "Loading libv4l2tracer: %s\n", libv4l2tracer_path.c_str()); setenv("LD_PRELOAD", libv4l2tracer_path.c_str(), 0);