{"id":22714,"url":"https://patchwork.libcamera.org/api/1.1/patches/22714/?format=json","web_url":"https://patchwork.libcamera.org/patch/22714/","project":{"id":1,"url":"https://patchwork.libcamera.org/api/1.1/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":"<20250130195811.1230581-6-pobrn@protonmail.com>","date":"2025-01-30T19:58:41","name":"[RFC,v2,5/9] libcamera: base: log: Use `std::string_view` to avoid some copies","commit_ref":null,"pull_url":null,"state":"superseded","archived":false,"hash":"6f0ae78c0101306d1fa70dec7b36ef0ad60151ea","submitter":{"id":133,"url":"https://patchwork.libcamera.org/api/1.1/people/133/?format=json","name":"Pőcze Barnabás","email":"pobrn@protonmail.com"},"delegate":null,"mbox":"https://patchwork.libcamera.org/patch/22714/mbox/","series":[{"id":4982,"url":"https://patchwork.libcamera.org/api/1.1/series/4982/?format=json","web_url":"https://patchwork.libcamera.org/project/libcamera/list/?series=4982","date":"2025-01-30T19:58:14","name":"libcamera: base: log: Misc. changes","version":2,"mbox":"https://patchwork.libcamera.org/series/4982/mbox/"}],"comments":"https://patchwork.libcamera.org/api/patches/22714/comments/","check":"pending","checks":"https://patchwork.libcamera.org/api/patches/22714/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 60389BD808\n\tfor ;\n\tThu, 30 Jan 2025 19:58:48 +0000 (UTC)","from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 1BD7068572;\n\tThu, 30 Jan 2025 20:58:48 +0100 (CET)","from mail-4322.protonmail.ch (mail-4322.protonmail.ch\n\t[185.70.43.22])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id 560AC6851B\n\tfor ;\n\tThu, 30 Jan 2025 20:58:46 +0100 (CET)"],"Authentication-Results":"lancelot.ideasonboard.com;\n\tdkim=fail reason=\"signature verification failed\" (2048-bit key;\n\tunprotected) header.d=protonmail.com header.i=@protonmail.com\n\theader.b=\"wN8PeKGr\"; dkim-atps=neutral","DKIM-Signature":"v=1; a=rsa-sha256; c=relaxed/relaxed; d=protonmail.com;\n\ts=protonmail3; t=1738267125; x=1738526325;\n\tbh=lUpm/1QNowLSz3JziR4VCi/4wAJywYeIWioU9X+eg+0=;\n\th=Date:To:From:Cc:Subject:Message-ID:In-Reply-To:References:\n\tFeedback-ID:From:To:Cc:Date:Subject:Reply-To:Feedback-ID:\n\tMessage-ID:BIMI-Selector:List-Unsubscribe:List-Unsubscribe-Post;\n\tb=wN8PeKGrqrcWIIwo7iJ+iHPapxyA3S5Kafz1DLQiNk05I5eKCwiRzR3SfK9pkvAda\n\tsVvdDzCdofmnyA6lKI4m+6xC7EBeFiLiGvUdotmgd+xozyUqhCWwUcOCoaHlbzQR3p\n\tWl5uZDjmetIcup9xqHHWxLm2efyXC3OxDUaKmu9QjhW1UzZXm4DS5/LQuH1QKEFG9Y\n\tII476hchEbHvp2sfIYtHqu6ymTs0u8z8f65Lx/yc4+0Cf8/O0lpMJIkAuItRxtjy3T\n\tBNcrMVg5JEAMrH531pPbxWD6uP6xRbnjUU83gdZVk9fsnMtbVDK6z449vRehSrGQkd\n\tXAzCF105D1BGw==","Date":"Thu, 30 Jan 2025 19:58:41 +0000","To":"libcamera-devel@lists.libcamera.org","From":"=?utf-8?q?Barnab=C3=A1s_P=C5=91cze?= ","Cc":"Laurent Pinchart ","Subject":"[RFC PATCH v2 5/9] libcamera: base: log: Use `std::string_view` to\n\tavoid some copies","Message-ID":"<20250130195811.1230581-6-pobrn@protonmail.com>","In-Reply-To":"<20250130195811.1230581-1-pobrn@protonmail.com>","References":"<20250130195811.1230581-1-pobrn@protonmail.com>","Feedback-ID":"20568564:user:proton","X-Pm-Message-ID":"e3bf1bcbf4e43f9c453191ef29587c44cb99a65e","MIME-Version":"1.0","Content-Type":"text/plain; charset=utf-8","Content-Transfer-Encoding":"quoted-printable","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","Errors-To":"libcamera-devel-bounces@lists.libcamera.org","Sender":"\"libcamera-devel\" "},"content":"Use `std::string_view` to avoid some largely unnecessary copies, and\nto make string comparisong potentially faster by eliminating repeated\n`strlen()` calls.\n\nSigned-off-by: Barnabás Pőcze \nReviewed-by: Laurent Pinchart \n---\n include/libcamera/base/log.h | 5 +++--\n src/libcamera/base/log.cpp | 25 +++++++++++++------------\n 2 files changed, 16 insertions(+), 14 deletions(-)","diff":"diff --git a/include/libcamera/base/log.h b/include/libcamera/base/log.h\nindex 4137d87a4..acef24203 100644\n--- a/include/libcamera/base/log.h\n+++ b/include/libcamera/base/log.h\n@@ -9,6 +9,7 @@\n \n #include \n #include \n+#include \n \n #include \n \n@@ -29,7 +30,7 @@ enum LogSeverity {\n class LogCategory\n {\n public:\n-\tstatic LogCategory *create(const char *name);\n+\tstatic LogCategory *create(std::string_view name);\n \n \tconst std::string &name() const { return name_; }\n \tLogSeverity severity() const { return severity_.load(std::memory_order_relaxed); }\n@@ -38,7 +39,7 @@ public:\n \tstatic const LogCategory &defaultCategory();\n \n private:\n-\texplicit LogCategory(const char *name);\n+\texplicit LogCategory(std::string_view name);\n \n \tconst std::string name_;\n \ndiff --git a/src/libcamera/base/log.cpp b/src/libcamera/base/log.cpp\nindex 2abbad478..9415b6937 100644\n--- a/src/libcamera/base/log.cpp\n+++ b/src/libcamera/base/log.cpp\n@@ -15,6 +15,7 @@\n #include \n #include \n #include \n+#include \n #include \n #include \n #include \n@@ -312,11 +313,11 @@ private:\n \n \tvoid parseLogFile();\n \tvoid parseLogLevels();\n-\tstatic LogSeverity parseLogLevel(const std::string &level);\n+\tstatic LogSeverity parseLogLevel(std::string_view level);\n \n \tfriend LogCategory;\n \tvoid registerCategory(LogCategory *category);\n-\tLogCategory *findCategory(const char *name) const;\n+\tLogCategory *findCategory(std::string_view name) const;\n \n \tstatic bool destroyed_;\n \n@@ -641,17 +642,17 @@ void Logger::parseLogLevels()\n \t\tif (!len)\n \t\t\tcontinue;\n \n-\t\tstd::string category;\n-\t\tstd::string level;\n+\t\tstd::string_view category;\n+\t\tstd::string_view level;\n \n \t\tconst char *colon = static_cast(memchr(pair, ':', len));\n \t\tif (!colon) {\n \t\t\t/* 'x' is a shortcut for '*:x'. */\n \t\t\tcategory = \"*\";\n-\t\t\tlevel = std::string(pair, len);\n+\t\t\tlevel = std::string_view(pair, len);\n \t\t} else {\n-\t\t\tcategory = std::string(pair, colon - pair);\n-\t\t\tlevel = std::string(colon + 1, comma - colon - 1);\n+\t\t\tcategory = std::string_view(pair, colon - pair);\n+\t\t\tlevel = std::string_view(colon + 1, comma - colon - 1);\n \t\t}\n \n \t\t/* Both the category and the level must be specified. */\n@@ -662,7 +663,7 @@ void Logger::parseLogLevels()\n \t\tif (severity == LogInvalid)\n \t\t\tcontinue;\n \n-\t\tlevels_.push_back({ category, severity });\n+\t\tlevels_.emplace_back(category, severity);\n \t}\n }\n \n@@ -676,7 +677,7 @@ void Logger::parseLogLevels()\n *\n * \\return The log severity, or LogInvalid if the string is invalid\n */\n-LogSeverity Logger::parseLogLevel(const std::string &level)\n+LogSeverity Logger::parseLogLevel(std::string_view level)\n {\n \tstatic const char *const names[] = {\n \t\t\"DEBUG\",\n@@ -743,7 +744,7 @@ void Logger::registerCategory(LogCategory *category)\n * \\param[in] name Name of the log category\n * \\return The pointer to the found log category or nullptr if not found\n */\n-LogCategory *Logger::findCategory(const char *name) const\n+LogCategory *Logger::findCategory(std::string_view name) const\n {\n \tif (auto it = std::find_if(categories_.begin(), categories_.end(),\n \t\t\t\t [name](auto c) { return c->name() == name; });\n@@ -787,7 +788,7 @@ LogCategory *Logger::findCategory(const char *name) const\n *\n * \\return The pointer to the LogCategory\n */\n-LogCategory *LogCategory::create(const char *name)\n+LogCategory *LogCategory::create(std::string_view name)\n {\n \tstatic Mutex mutex_;\n \tMutexLocker locker(mutex_);\n@@ -805,7 +806,7 @@ LogCategory *LogCategory::create(const char *name)\n * \\brief Construct a log category\n * \\param[in] name The category name\n */\n-LogCategory::LogCategory(const char *name)\n+LogCategory::LogCategory(std::string_view name)\n \t: name_(name), severity_(LogSeverity::LogInfo)\n {\n }\n","prefixes":["RFC","v2","5/9"]}