QLockFile: fix errno handling

In case of a lock failure, we potentially pollute the errno value
before printing it. Also, switch to qt_error_string, as strerror
is not reentrant.

Change-Id: I952aac14204637155726bcefc0ed8a21d7fcd501
Reviewed-by: David Faure <david.faure@kdab.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/src/corelib/io/qlockfile_unix.cpp b/src/corelib/io/qlockfile_unix.cpp
index 5ff4b1cbe1..bd9f8a5988 100644
--- a/src/corelib/io/qlockfile_unix.cpp
+++ b/src/corelib/io/qlockfile_unix.cpp
@@ -171,8 +171,10 @@ QLockFile::LockError QLockFilePrivate::tryLock_sys()
         }
     }
     // Ensure nobody else can delete the file while we have it
-    if (!setNativeLocks(fd))
-        qWarning() << "setNativeLocks failed:" << strerror(errno);
+    if (!setNativeLocks(fd)) {
+        const int errnoSaved = errno;
+        qWarning() << "setNativeLocks failed:" << qt_error_string(errnoSaved);
+    }
 
     if (qt_write_loop(fd, fileData.constData(), fileData.size()) < fileData.size()) {
         close(fd);