Handle the situation where QTemporaryFile::open() fails

If open() fails then we should make sure we do not try to write to it
and just return 0 in that case.

Change-Id: I2980b65766b322efed6708fb10cc27567174dc37
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 13 insertions, 9 deletions

diff --git a/src/corelib/io/qtemporaryfile.cpp b/src/corelib/io/qtemporaryfile.cpp
index 7e3be9ef36..35bb465a04 100644
--- a/src/corelib/io/qtemporaryfile.cpp
+++ b/src/corelib/io/qtemporaryfile.cpp
@@ -912,16 +912,20 @@ QTemporaryFile *QTemporaryFile::createNativeFile(QFile &file)
             file.open(QIODevice::ReadOnly);
         //dump data
         QTemporaryFile *ret = new QTemporaryFile;
-        ret->open();
-        file.seek(0);
-        char buffer[1024];
-        while(true) {
-            qint64 len = file.read(buffer, 1024);
-            if(len < 1)
-                break;
-            ret->write(buffer, len);
+        if (ret->open()) {
+            file.seek(0);
+            char buffer[1024];
+            while (true) {
+                qint64 len = file.read(buffer, 1024);
+                if (len < 1)
+                    break;
+                ret->write(buffer, len);
+            }
+            ret->seek(0);
+        } else {
+            delete ret;
+            ret = nullptr;
         }
-        ret->seek(0);
         //restore
         if(wasOpen)
             file.seek(old_off);