Add support for protected payloads

Add support for protected payloads. The new `intranpayload' option can
be used to specify a translation function translating payloads to
values of the translated type.  This function will be used instead of
the `intran' function to to look up the receiving object of a message
in a server.

This makes it easy to use the protected payloads introduced in GNU
Mach 1.5.

An inTransPayload function translates payloads to objects, like an
inTrans function translates from port names to objects.  Generate code
in the server routine to optimize lookups to the receiver of the
message.

Additionally, if no intran function is provided, but an intranpayload
function is, it is expected to translate from payloads to port names.
This is used to preserve the semantics in case the server routine
expects a port name.

* NEWS: Add item.
* lexxer.l: Emit syInTranPayload.
* parser.h: Define syInTranPayload.
* parser.y (TransTypeSpec): Handle syInTranPayload.
* type.h (struct ipc_type): Add itInTransPayload.
* server.c (WriteExtractArgValue): If a payload-aware intrans function
has been specified, use it to get a reference to the receiving object.
* routine.c (rtAugmentArgKind): Force the use of a local variable if a
payload-aware translate-in function is defined.

1 files changed, 9 insertions, 1 deletions

diff --git a/type.c b/type.c
index 3078dab..7565f34 100644
--- a/type.c
+++ b/type.c
@@ -118,6 +118,7 @@ itAlloc(void)
 	strNULL,		/* identifier_t itServerType */
 	strNULL,		/* identifier_t itTransType */
 	strNULL,		/* identifier_t itInTrans */
+	strNULL,		/* identifier_t itInTransPayload */
 	strNULL,		/* identifier_t itOutTrans */
 	strNULL,		/* identifier_t itDestructor */
     };
@@ -376,7 +377,9 @@ itCheckDecl(identifier_t name, ipc_type_t *it)
        limitations in Mig */
 
     if (it->itVarArray) {
-	if ((it->itInTrans != strNULL) || (it->itOutTrans != strNULL))
+	if ((it->itInTrans != strNULL) ||
+	    (it->itInTransPayload != strNULL) ||
+	    (it->itOutTrans != strNULL))
 	    error("%s: can't translate variable-sized arrays", name);
 
 	if (it->itDestructor != strNULL)
@@ -419,6 +422,10 @@ itPrintTrans(const ipc_type_t *it)
        printf("\tInTran:\t\t%s %s(%s)\n",
 	      it->itTransType, it->itInTrans, it->itServerType);
 
+    if (it->itInTransPayload != strNULL)
+       printf("\tInTranPayload:\t\t%s %s\n",
+	      it->itTransType, it->itInTransPayload);
+
     if (it->itOutTrans != strNULL)
        printf("\tOutTran:\t%s %s(%s)\n",
 	      it->itServerType, it->itOutTrans, it->itTransType);
@@ -556,6 +563,7 @@ itResetType(ipc_type_t *old)
     /* reset all special translation/destruction/type info */
 
     old->itInTrans = strNULL;
+    old->itInTransPayload = strNULL;
     old->itOutTrans = strNULL;
     old->itDestructor = strNULL;
     old->itUserType = strNULL;