From 29ec6fada935ef966e5859082435ed57daa9522d Mon Sep 17 00:00:00 2001 From: Samuel Dionne-Riel Date: Tue, 16 Mar 2021 15:03:59 -0400 Subject: [PATCH] [NixOS] Unwrap executable name for .desktop search Why is this necessary even though -a "$0" is used in the wrapper? Because it's completely bypassing argv0! This looks at the executable file in-use according to the kernel! Wrappers cannot affect the `/proc/.../exe` symlink! --- service_utils.h | 28 +++++++++++++++++++++++++++- 1 file changed, 27 insertions(+), 1 deletion(-) diff --git a/service_utils.h b/service_utils.h index 8a70c1fad..6674f553b 100644 --- a/service_utils.h +++ b/service_utils.h @@ -26,8 +26,34 @@ namespace KWin const static QString s_waylandInterfaceName = QStringLiteral("X-KDE-Wayland-Interfaces"); const static QString s_dbusRestrictedInterfaceName = QStringLiteral("X-KDE-DBUS-Restricted-Interfaces"); -static QStringList fetchProcessServiceField(const QString &executablePath, const QString &fieldName) +static QStringList fetchProcessServiceField(const QString &in_executablePath, const QString &fieldName) { + // !! Start NixOS fix + // NixOS fixes many packaging issues through "wrapper" scripts that manipulates the environment or does + // miscellaneous trickeries and mischievous things to make the programs work. + // In turn, programs often employs different mischievous schemes and trickeries to do *other things. + // It often happens that they conflict. + // Here, `kwin` tries to detect the .desktop file for a given process. + // `kwin` followed the process `/proc/.../exe` up to the actual binary running. + // It normally would be fine, e.g. /usr/bin/foobar is what's in the desktop file. + // But it's not the truth here! It's extremely likely the resolved path is /nix/store/.../bin/.foobar-wrapped + // rather than what the desktop file points to, something like /nix/store/.../bin/foobar !! + // Since the wrappers for Nixpkgs *always* prepend a dot and append -wrapped, we assume here that we can keep + // `/^(.*)\/\.([^/]*)-wrapped/` until the (equivalent) regex does not match. + // This should canonicalize the wrapper name to the expected name to look for in the desktop file. + + // Use a copy of the const string + QString executablePath(in_executablePath); + + // While the parts needed are present, "unwrap" one layer of wrapper names. + while (executablePath.endsWith("-wrapped") && executablePath[executablePath.lastIndexOf("/")+1] == QChar('.')) { + // Approximately equivalent to s/-wrapped$// + executablePath.remove(executablePath.length() - 8, 8); + // Approximately equivalent to s;/\.;/; + executablePath.remove(executablePath.lastIndexOf("/")+1, 1); + } + // !! End NixOS fix + // needed to be able to use the logging category in a header static function static QLoggingCategory KWIN_UTILS ("KWIN_UTILS", QtWarningMsg); const auto servicesFound = KApplicationTrader::query([&executablePath] (const KService::Ptr &service) { -- 2.28.0