avoid gcc warnings for libSM

  Patch from http://bugs.freedesktop.org/show_bug.cgi?id=17968 adapted
to current sources.
  This corrects a potential (hypothetical) segmentation fault.

2 files changed, 10 insertions, 16 deletions

diff --git a/src/SMlibint.h b/src/SMlibint.h
index 0569c3f..387f0bd 100644
--- a/src/SMlibint.h
+++ b/src/SMlibint.h
@@ -207,11 +207,9 @@ in this Software without prior written authorization from The Open Group.
 #define STORE_ARRAY8(_pBuf, _len, _array8) \
 { \
     STORE_CARD32 (_pBuf, _len); \
-    if (_array8) \
-	memcpy (_pBuf, _array8, _len); \
-    _pBuf += _len; \
-    if (PAD64 (4 + _len)) \
-        _pBuf += PAD64 (4 + _len); \
+    if (_len) \
+        memcpy (_pBuf, _array8, _len); \
+    _pBuf += _len + PAD64 (4 + _len); \
 }
 
 #define STORE_LISTOF_PROPERTY(_pBuf, _count, _props) \
@@ -244,9 +242,7 @@ in this Software without prior written authorization from The Open Group.
     _array8 = (char *) malloc (_len + 1); \
     memcpy (_array8, _pBuf, _len); \
     _array8[_len] = '\0'; \
-    _pBuf += _len; \
-    if (PAD64 (4 + _len)) \
-        _pBuf += PAD64 (4 + _len); \
+    _pBuf += _len + PAD64 (4 + _len); \
 }
 
 #define EXTRACT_ARRAY8_AS_STRING(_pBuf, _swap, _string) \
@@ -256,9 +252,7 @@ in this Software without prior written authorization from The Open Group.
     _string = (char *) malloc (_len + 1); \
     memcpy (_string, _pBuf, _len); \
     _string[_len] = '\0'; \
-    _pBuf += _len; \
-    if (PAD64 (4 + _len)) \
-        _pBuf += PAD64 (4 + _len); \
+    _pBuf += _len + PAD64 (4 + _len); \
 }
 
 #define EXTRACT_LISTOF_PROPERTY(_pBuf, _swap, _count, _props) \
@@ -290,9 +284,7 @@ in this Software without prior written authorization from The Open Group.
 { \
     CARD32 _len; \
     EXTRACT_CARD32 (_pBuf, _swap, _len); \
-    _pBuf += _len; \
-    if (PAD64 (4 + _len)) \
-        _pBuf += PAD64 (4 + _len); \
+    _pBuf += _len + PAD64 (4 + _len); \
 }
 
 #define SKIP_LISTOF_PROPERTY(_pBuf, _swap) \
diff --git a/src/sm_client.c b/src/sm_client.c
index 778a740..de79452 100644
--- a/src/sm_client.c
+++ b/src/sm_client.c
@@ -197,7 +197,9 @@ char 		*errorStringRet;
      * Now register the client
      */
 
-    len = previousId ? strlen (previousId) : 0;
+    if (!previousId)
+	previousId = "";
+    len = strlen (previousId);
     extra = ARRAY8_BYTES (len);
 
     IceGetHeaderExtra (iceConn, _SmcOpcode, SM_RegisterClient,
@@ -263,7 +265,7 @@ char 		*errorStringRet;
 		    SIZEOF (smRegisterClientMsg), WORD64COUNT (extra),
 		    smRegisterClientMsg, pMsg, pData);
 
-		STORE_ARRAY8 (pData, 0, NULL);
+		STORE_ARRAY8 (pData, 0, "");
 
 		IceFlush (iceConn);