Fixed app freeze if switching to offline in middle of HTTP transaction.

When active socket is disconnected by swithcing to offline mode, native
RSocket completes the active socket operations with KErrCancel (-3).
Open C maps this error code to POSIX errno EINTR (4). Normally in Posix
EINTR is only used to indicate that some operation was interrupted by
POSIX signal. Qt has a while loops in network operations to handle
operations interrupterd by signals. These while loops will be
effectively forever loops in Symbian due to Open C error code mapping.

Because Symbian does not have native support for signals, i.e. the
network operations can never be really interrupted by POSIX signal,
it is ok to remove these while loops completely on Symbian platform.

This fix is a workaround to Open C incorrect error mapping, and
should be removed once Open C has fixed their error mapping.

Task-number: QT-3274
Reviewed-by: Aleksandar Sasha Babic

1 files changed, 20 insertions, 9 deletions

diff --git a/src/network/socket/qnativesocketengine_unix.cpp b/src/network/socket/qnativesocketengine_unix.cpp
index 9a2c349..354c944 100644
--- a/src/network/socket/qnativesocketengine_unix.cpp
+++ b/src/network/socket/qnativesocketengine_unix.cpp
@@ -601,10 +601,15 @@ bool QNativeSocketEnginePrivate::nativeHasPendingDatagrams() const
     // Peek 0 bytes into the next message. The size of the message may
     // well be 0, so we can't check recvfrom's return value.
     ssize_t readBytes;
+#ifdef Q_OS_SYMBIAN
+    char c;
+    readBytes = ::recvfrom(socketDescriptor, &c, 1, MSG_PEEK, &storage.a, &storageSize);
+#else
     do {
         char c;
         readBytes = ::recvfrom(socketDescriptor, &c, 1, MSG_PEEK, &storage.a, &storageSize);
     } while (readBytes == -1 && errno == EINTR);
+#endif
 
     // If there's no error, or if our buffer was too small, there must be a
     // pending datagram.
@@ -661,11 +666,17 @@ qint64 QNativeSocketEnginePrivate::nativeReceiveDatagram(char *data, qint64 maxS
     sz = sizeof(aa);
 
     ssize_t recvFromResult = 0;
+#ifdef Q_OS_SYMBIAN
+    char c;
+    recvFromResult = ::recvfrom(socketDescriptor, maxSize ? data : &c, maxSize ? maxSize : 1,
+                                0, &aa.a, &sz);
+#else
     do {
         char c;
         recvFromResult = ::recvfrom(socketDescriptor, maxSize ? data : &c, maxSize ? maxSize : 1,
                                     0, &aa.a, &sz);
     } while (recvFromResult == -1 && errno == EINTR);
+#endif
 
     if (recvFromResult == -1) {
         setError(QAbstractSocket::NetworkError, ReceiveDatagramErrorString);
@@ -832,17 +843,17 @@ qint64 QNativeSocketEnginePrivate::nativeWrite(const char *data, qint64 len)
     // ignore the SIGPIPE signal
     qt_ignore_sigpipe();
 
-    // loop while ::write() returns -1 and errno == EINTR, in case
-    // of an interrupting signal.
     ssize_t writtenBytes;
-    do {
 #ifdef Q_OS_SYMBIAN
-	    writtenBytes = ::write(socketDescriptor, data, len);
+    // Symbian does not support signals natively and Open C returns EINTR when moving to offline
+    writtenBytes = ::write(socketDescriptor, data, len);
 #else
+    // loop while ::write() returns -1 and errno == EINTR, in case
+    // of an interrupting signal.
+    do {
         writtenBytes = qt_safe_write(socketDescriptor, data, len);
-#endif
-        // writtenBytes = QT_WRITE(socketDescriptor, data, len); ### TODO S60: Should this line be removed or the one above it?
     } while (writtenBytes < 0 && errno == EINTR);
+#endif
 
     if (writtenBytes < 0) {
         switch (errno) {
@@ -882,13 +893,13 @@ qint64 QNativeSocketEnginePrivate::nativeRead(char *data, qint64 maxSize)
     }
 
     ssize_t r = 0;
-    do {
 #ifdef Q_OS_SYMBIAN
-        r = ::read(socketDescriptor, data, maxSize);
+    r = ::read(socketDescriptor, data, maxSize);
 #else
+    do {
         r = qt_safe_read(socketDescriptor, data, maxSize);
-#endif
     } while (r == -1 && errno == EINTR);
+#endif
 
     if (r < 0) {
         r = -1;