Avoid redundant string length scan

PR #21807.

src/base/bittorrent/sessionimpl.cpp

@@ -86,6 +86,7 @@
 #include "base/utils/net.h"
 #include "base/utils/number.h"
 #include "base/utils/random.h"
+#include "base/utils/string.h"
 #include "base/version.h"
 #include "bandwidthscheduler.h"
 #include "bencoderesumedatastorage.h"
@@ -222,7 +223,7 @@ namespace
     {
         try
         {
-            return QString::fromLatin1(address.to_string().c_str());
+            return Utils::String::fromLatin1(address.to_string());
         }
         catch (const std::exception &)
         {
@@ -5831,7 +5832,7 @@ void SessionImpl::handleTorrentDeleteFailedAlert(const lt::torrent_delete_failed
 #else
     const auto torrentID = TorrentID::fromInfoHash(alert->info_hash);
 #endif
-    const auto errorMessage = alert->error ? QString::fromLocal8Bit(alert->error.message().c_str()) : QString();
+    const auto errorMessage = alert->error ? Utils::String::fromLocal8Bit(alert->error.message()) : QString();
     handleRemovedTorrent(torrentID, errorMessage);
 }
 
@@ -5989,7 +5990,7 @@ void SessionImpl::handleListenFailedAlert(const lt::listen_failed_alert *alert)
     const QString proto {toString(alert->socket_type)};
     LogMsg(tr("Failed to listen on IP. IP: \"%1\". Port: \"%2/%3\". Reason: \"%4\"")
         .arg(toString(alert->address), proto, QString::number(alert->port)
-            , QString::fromLocal8Bit(alert->error.message().c_str())), Log::CRITICAL);
+            , Utils::String::fromLocal8Bit(alert->error.message())), Log::CRITICAL);
 }
 
 void SessionImpl::handleExternalIPAlert(const lt::external_ip_alert *alert)
@@ -6215,7 +6216,7 @@ void SessionImpl::handleSocks5Alert(const lt::socks5_alert *alert) const
         const QString endpoint = (addr.is_v6() ? u"[%1]:%2"_s : u"%1:%2"_s)
                 .arg(QString::fromStdString(addr.to_string()), QString::number(alert->ip.port()));
         LogMsg(tr("SOCKS5 proxy error. Address: %1. Message: \"%2\".")
-                .arg(endpoint, QString::fromLocal8Bit(alert->error.message().c_str()))
+                .arg(endpoint, Utils::String::fromLocal8Bit(alert->error.message()))
                 , Log::WARNING);
     }
 }

src/base/bittorrent/torrentimpl.cpp

@@ -63,6 +63,7 @@
 #include "base/types.h"
 #include "base/utils/fs.h"
 #include "base/utils/io.h"
+#include "base/utils/string.h"
 #include "common.h"
 #include "downloadpriority.h"
 #include "extensiondata.h"
@@ -100,8 +101,7 @@ namespace
         if (const QString *endpointName = cache.object(ltTCPEndpoint))
             return *endpointName;
 
-        const std::string tmp = (std::ostringstream() << ltTCPEndpoint).str();
+        const auto endpointName = Utils::String::fromLatin1((std::ostringstream() << ltTCPEndpoint).str());
-        const auto endpointName = QString::fromLatin1(tmp.c_str(), tmp.size());
         cache.insert(ltTCPEndpoint, new QString(endpointName));
         return endpointName;
     }
@@ -1255,12 +1255,12 @@ int TorrentImpl::queuePosition() const
 QString TorrentImpl::error() const
 {
     if (m_nativeStatus.errc)
-        return QString::fromLocal8Bit(m_nativeStatus.errc.message().c_str());
+        return Utils::String::fromLocal8Bit(m_nativeStatus.errc.message());
 
     if (m_nativeStatus.flags & lt::torrent_flags::upload_mode)
     {
         return tr("Couldn't write to file. Reason: \"%1\". Torrent is now in \"upload only\" mode.")
-            .arg(QString::fromLocal8Bit(m_lastFileError.error.message().c_str()));
+            .arg(Utils::String::fromLocal8Bit(m_lastFileError.error.message()));
     }
 
     return {};
@@ -2277,7 +2277,7 @@ void TorrentImpl::handleSaveResumeDataFailedAlert(const lt::save_resume_data_fai
     if (p->error != lt::errors::resume_data_not_modified)
     {
         LogMsg(tr("Generate resume data failed. Torrent: \"%1\". Reason: \"%2\"")
-            .arg(name(), QString::fromLocal8Bit(p->error.message().c_str())), Log::CRITICAL);
+            .arg(name(), Utils::String::fromLocal8Bit(p->error.message())), Log::CRITICAL);
     }
 }
 
@@ -2365,7 +2365,7 @@ void TorrentImpl::handleFileRenameFailedAlert(const lt::file_rename_failed_alert
     Q_ASSERT(fileIndex >= 0);
 
     LogMsg(tr("File rename failed. Torrent: \"%1\", file: \"%2\", reason: \"%3\"")
-        .arg(name(), filePath(fileIndex).toString(), QString::fromLocal8Bit(p->error.message().c_str())), Log::WARNING);
+        .arg(name(), filePath(fileIndex).toString(), Utils::String::fromLocal8Bit(p->error.message())), Log::WARNING);
 
     --m_renameCount;
     while (!isMoveInProgress() && (m_renameCount == 0) && !m_moveFinishedTriggers.isEmpty())

src/base/utils/string.cpp

@@ -49,6 +49,16 @@ QString Utils::String::fromDouble(const double n, const int precision)
     return QLocale::system().toString(std::floor(n * prec) / prec, 'f', precision);
 }
 
+QString Utils::String::fromLatin1(const std::string &string)
+{
+    return QString::fromLatin1(string.c_str(), string.size());
+}
+
+QString Utils::String::fromLocal8Bit(const std::string &string)
+{
+    return QString::fromLocal8Bit(string.c_str(), string.size());
+}
+
 QString Utils::String::wildcardToRegexPattern(const QString &pattern)
 {
     return QRegularExpression::wildcardToRegularExpression(pattern, QRegularExpression::UnanchoredWildcardConversion);

src/base/utils/string.h

@@ -66,6 +66,8 @@ namespace Utils::String
     QStringList splitCommand(const QString &command);
 
     QString fromDouble(double n, int precision);
+    QString fromLatin1(const std::string &string);
+    QString fromLocal8Bit(const std::string &string);
 
     template <typename Container>
     QString joinIntoString(const Container &container, const QString &separator)