Preserve constness in casting arguments through the Data*() routines

Casts were annoying gcc by dropping constness when changing types,
when routines simply either copy data into the request buffer or
send it directly to the X server, and never modify the input.

Fixes gcc warnings including:
ChProp.c: In function 'XChangeProperty':
ChProp.c:65:6: warning: cast discards '__attribute__((const))' qualifier from pointer target type [-Wcast-qual]
ChProp.c:65:6: warning: cast discards '__attribute__((const))' qualifier from pointer target type [-Wcast-qual]
ChProp.c:74:6: warning: cast discards '__attribute__((const))' qualifier from pointer target type [-Wcast-qual]
ChProp.c:74:6: warning: cast discards '__attribute__((const))' qualifier from pointer target type [-Wcast-qual]
ChProp.c:83:6: warning: cast discards '__attribute__((const))' qualifier from pointer target type [-Wcast-qual]
SetHints.c: In function 'XSetStandardProperties':
SetHints.c:262:20: warning: cast discards '__attribute__((const))' qualifier from pointer target type [-Wcast-qual]
SetPntMap.c: In function 'XSetPointerMapping':
SetPntMap.c:46:5: warning: cast discards '__attribute__((const))' qualifier from pointer target type [-Wcast-qual]
SetPntMap.c:46:5: warning: cast discards '__attribute__((const))' qualifier from pointer target type [-Wcast-qual]
StBytes.c: In function 'XStoreBuffer':
StBytes.c:97:33: warning: cast discards '__attribute__((const))' qualifier from pointer target type [-Wcast-qual]
StName.c: In function 'XStoreName':
StName.c:40:27: warning: cast discards '__attribute__((const))' qualifier from pointer target type [-Wcast-qual]
StName.c: In function 'XSetIconName':
StName.c:51:27: warning: cast discards '__attribute__((const))' qualifier from pointer target type [-Wcast-qual]

Signed-off-by: Alan Coopersmith <alan.coopersmith@oracle.com>

6 files changed, 17 insertions, 15 deletions

diff --git a/src/ChProp.c b/src/ChProp.c
index b9577512..190a224f 100644
--- a/src/ChProp.c
+++ b/src/ChProp.c
@@ -62,7 +62,7 @@ XChangeProperty (
 	len = ((long)nelements + 3)>>2;
 	if (dpy->bigreq_size || req->length + len <= (unsigned) 65535) {
 	    SetReqLen(req, len, len);
-	    Data (dpy, (char *)data, nelements);
+	    Data (dpy, (_Xconst char *)data, nelements);
 	} /* else force BadLength */
         break;
 
@@ -71,7 +71,7 @@ XChangeProperty (
 	if (dpy->bigreq_size || req->length + len <= (unsigned) 65535) {
 	    SetReqLen(req, len, len);
 	    len = (long)nelements << 1;
-	    Data16 (dpy, (short *) data, len);
+	    Data16 (dpy, (_Xconst short *) data, len);
 	} /* else force BadLength */
 	break;
 
@@ -80,7 +80,7 @@ XChangeProperty (
 	if (dpy->bigreq_size || req->length + len <= (unsigned) 65535) {
 	    SetReqLen(req, len, len);
 	    len = (long)nelements << 2;
-	    Data32 (dpy, (long *) data, len);
+	    Data32 (dpy, (_Xconst long *) data, len);
 	} /* else force BadLength */
 	break;
 
diff --git a/src/SetHints.c b/src/SetHints.c
index 0c33f590..1cde48f8 100644
--- a/src/SetHints.c
+++ b/src/SetHints.c
@@ -259,7 +259,9 @@ XSetStandardProperties (
 
 	if (icon_string != NULL) {
 	    XChangeProperty (dpy, w, XA_WM_ICON_NAME, XA_STRING, 8,
-		PropModeReplace, (unsigned char *)icon_string, safestrlen(icon_string));
+                             PropModeReplace,
+                             (_Xconst unsigned char *)icon_string,
+                             safestrlen(icon_string));
 		}
 
 	if (icon_pixmap != None) {
diff --git a/src/SetPntMap.c b/src/SetPntMap.c
index 2e292019..14e104d6 100644
--- a/src/SetPntMap.c
+++ b/src/SetPntMap.c
@@ -43,7 +43,7 @@ XSetPointerMapping (
     GetReq (SetPointerMapping, req);
     req->nElts = nmaps;
     req->length += (nmaps + 3)>>2;
-    Data (dpy, (char *)map, (long) nmaps);
+    Data (dpy, (_Xconst char *)map, (long) nmaps);
     if (_XReply (dpy, (xReply *)&rep, 0, xFalse) == 0)
 	rep.success = MappingSuccess;
     UnlockDisplay(dpy);
diff --git a/src/StBytes.c b/src/StBytes.c
index 13ac879c..07ee441a 100644
--- a/src/StBytes.c
+++ b/src/StBytes.c
@@ -94,7 +94,7 @@ XStoreBuffer (
 {
     if ((buffer < 0) || (buffer > 7)) return 0;
     return XChangeProperty(dpy, RootWindow(dpy, 0), n_to_atom[buffer],
-	XA_STRING, 8, PropModeReplace, (unsigned char *) bytes, nbytes);
+	XA_STRING, 8, PropModeReplace, (_Xconst unsigned char *) bytes, nbytes);
 }
 
 int
diff --git a/src/StName.c b/src/StName.c
index fb1e6f5e..b4048bff 100644
--- a/src/StName.c
+++ b/src/StName.c
@@ -37,7 +37,7 @@ XStoreName (
     _Xconst char *name)
 {
     return XChangeProperty(dpy, w, XA_WM_NAME, XA_STRING,
-			   8, PropModeReplace, (unsigned char *)name,
+			   8, PropModeReplace, (_Xconst unsigned char *)name,
 			   name ? strlen(name) : 0);
 }
 
@@ -47,7 +47,7 @@ XSetIconName (
     Window w,
     _Xconst char *icon_name)
 {
-    return XChangeProperty(dpy, w, XA_WM_ICON_NAME, XA_STRING,
-			   8, PropModeReplace, (unsigned char *)icon_name,
+    return XChangeProperty(dpy, w, XA_WM_ICON_NAME, XA_STRING, 8,
+                           PropModeReplace, (_Xconst unsigned char *)icon_name,
 			   icon_name ? strlen(icon_name) : 0);
 }
diff --git a/src/XlibInt.c b/src/XlibInt.c
index 2827c106..e4d35fdc 100644
--- a/src/XlibInt.c
+++ b/src/XlibInt.c
@@ -1722,7 +1722,7 @@ void _Xbcopy(b1, b2, length)
 #ifdef DataRoutineIsProcedure
 void Data(
 	Display *dpy,
-	char *data,
+	_Xconst char *data,
 	long len)
 {
 	if (dpy->bufptr + (len) <= dpy->bufmax) {
@@ -1739,7 +1739,7 @@ void Data(
 int
 _XData32(
     Display *dpy,
-    register long *data,
+    register _Xconst long *data,
     unsigned len)
 {
     register int *buf;
@@ -1781,7 +1781,7 @@ _XData32(
 
 static doData16(
     register Display *dpy,
-    short *data,
+    _Xconst short *data,
     unsigned len,
     char *packbuffer)
 {
@@ -1814,7 +1814,7 @@ static doData16(
 
 _XData16 (
     Display *dpy,
-    short *data,
+    _Xconst short *data,
     unsigned len)
 {
     char packbuffer[PACKBUFFERSIZE];
@@ -1836,7 +1836,7 @@ _XData16 (
 
 static doData32(
     register Display *dpy
-    long *data,
+    _Xconst long *data,
     unsigned len,
     char *packbuffer)
 {
@@ -1867,7 +1867,7 @@ static doData32(
 
 void _XData32(
     Display *dpy,
-    long *data,
+    _Xconst long *data,
     unsigned len)
 {
     char packbuffer[PACKBUFFERSIZE];