subsurface/core/gettextfromc.cpp

// SPDX-License-Identifier: GPL-2.0
#include "gettextfromc.h"
#include <QHash>
#include <QMutex>

static QHash<QByteArray, QByteArray> translationCache;
static QMutex lock;

extern "C" const char *trGettext(const char *text)
{
	QByteArray key(text);
	QMutexLocker l(&lock);
	auto it = translationCache.find(key);
	if (it == translationCache.end())
		it = translationCache.insert(key, gettextFromC::tr(text).toUtf8());
	return it->constData();
}
Add SPDX header to remaining core files Signed-off-by: Dirk Hohndel <dirk@hohndel.org> 2017-04-27 18:24:53 +00:00			`// SPDX-License-Identifier: GPL-2.0`
Move subsurface-core to core and qt-mobile to mobile-widgets Having subsurface-core as a directory name really messes with autocomplete and is obviously redundant. Simmilarly, qt-mobile caused an autocomplete conflict and also was inconsistent with the desktop-widget name for the directory containing the "other" UI. And while cleaning up the resulting change in the path name for include files, I decided to clean up those even more to make them consistent overall. This could have been handled in more commits, but since this requires a make clean before the build, it seemed more sensible to do it all in one. Signed-off-by: Dirk Hohndel <dirk@hohndel.org> 2016-04-05 05:02:03 +00:00			`#include "gettextfromc.h"`
Localization: remove gettextFromC::instance() There were a handfull instances of the kind 1) gettextFromC::instance()->tr(...) 2) gettextFromC::instance()->trGettext(...) 1) is pointless, as tr is a static function. All instances of 2) were likewise pointless, because trGettext() returns a C-string, which was then immediately converted to a QString. Thus, replace both constructs by gettextFromC::tr(...). After this change there was only one user of gettextFromC::instance() left, viz. the C-interface funtion trGettext(). Therefore, remove gettextFromC::instance() and do all the caching / translating directly in the global trGettext(). Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at> 2018-06-17 19:03:16 +00:00			`#include <QHash>`
Localization: make cache thread safe and robust against use-after-free The old trGettext() was not thread-safe and the returned C-strings could be freed in the case of empty translations strings. Therefore: 1) Introduce a mutex protecting access to the cache. 2) Never change existing entries, even if the translation string is empty. Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at> 2018-06-17 21:28:44 +00:00			`#include <QMutex>`
Trying to switch to Qt translation This compiles and looks about right, but it doesn't appear to work, yet. Signed-off-by: Dirk Hohndel <dirk@hohndel.org> 2013-10-06 15:55:58 +00:00
Localization: remove gettextFromC::instance() There were a handfull instances of the kind 1) gettextFromC::instance()->tr(...) 2) gettextFromC::instance()->trGettext(...) 1) is pointless, as tr is a static function. All instances of 2) were likewise pointless, because trGettext() returns a C-string, which was then immediately converted to a QString. Thus, replace both constructs by gettextFromC::tr(...). After this change there was only one user of gettextFromC::instance() left, viz. the C-interface funtion trGettext(). Therefore, remove gettextFromC::instance() and do all the caching / translating directly in the global trGettext(). Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at> 2018-06-17 19:03:16 +00:00			`static QHash<QByteArray, QByteArray> translationCache;`
Localization: make cache thread safe and robust against use-after-free The old trGettext() was not thread-safe and the returned C-strings could be freed in the case of empty translations strings. Therefore: 1) Introduce a mutex protecting access to the cache. 2) Never change existing entries, even if the translation string is empty. Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at> 2018-06-17 21:28:44 +00:00			`static QMutex lock;`
Localization: remove gettextFromC::instance() There were a handfull instances of the kind 1) gettextFromC::instance()->tr(...) 2) gettextFromC::instance()->trGettext(...) 1) is pointless, as tr is a static function. All instances of 2) were likewise pointless, because trGettext() returns a C-string, which was then immediately converted to a QString. Thus, replace both constructs by gettextFromC::tr(...). After this change there was only one user of gettextFromC::instance() left, viz. the C-interface funtion trGettext(). Therefore, remove gettextFromC::instance() and do all the caching / translating directly in the global trGettext(). Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at> 2018-06-17 19:03:16 +00:00
			`extern "C" const char trGettext(const char text)`
Trying to switch to Qt translation This compiles and looks about right, but it doesn't appear to work, yet. Signed-off-by: Dirk Hohndel <dirk@hohndel.org> 2013-10-06 15:55:58 +00:00			`{`
Localization: make cache thread safe and robust against use-after-free The old trGettext() was not thread-safe and the returned C-strings could be freed in the case of empty translations strings. Therefore: 1) Introduce a mutex protecting access to the cache. 2) Never change existing entries, even if the translation string is empty. Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at> 2018-06-17 21:28:44 +00:00			`QByteArray key(text);`
			`QMutexLocker l(&lock);`
			`auto it = translationCache.find(key);`
			`if (it == translationCache.end())`
			`it = translationCache.insert(key, gettextFromC::tr(text).toUtf8());`
			`return it->constData();`
Avoid the memory leaks from translations Instead use a hash to cache the translations (and allow for the ability to clear the hash so we can even switch translations at runtime...). Now Qt will keep track of the memory and release it for us when we are done with it. This avoids the memory leak introduced in commit 4ecb35bf5ff2 ("Make a copy of the translated text"). Signed-off-by: Dirk Hohndel <dirk@hohndel.org> 2013-10-09 05:44:38 +00:00			`}`