IC: Add structure documentation

Author: Goldfish64

MacHyperVSupport/IntegrationComponents/HyperVIC.hpp

@@ -17,45 +17,74 @@
 #define kHyperVICVersionV3    VMBUS_VERSION(3, 0)
 
 //
-// Message types.
+// IC message types.
 //
 typedef enum : UInt16 {
+  // IC general negotiation.
   kVMBusICMessageTypeNegotiate    = 0,
+  // Heartbeat component.
   kVMBusICMessageTypeHeartbeat    = 1,
+  // KVP component.
   kVMBusICMessageTypeKVPExchange  = 2,
+  // Guest shutdown component.
   kVMBusICMessageTypeShutdown     = 3,
+  // Time sync component.
   kVMBusICMessageTypeTimeSync     = 4,
+  // Snapshot (VSS) component.
   kVMBusICMessageTypeSnapshot     = 5,
+  // File copy component.
   kVMBusICMessageTypeFileCopy     = 7
 } VMBusICMessageType;
 
+// IC message is part of a transaction.
 #define kVMBusICFlagTransaction   1
+// IC message is from host to guest.
 #define kVMBusICFlagRequest       2
+// IC message is from guest to host.
 #define kVMBusICFlagResponse      4
 
 //
-// Header and common negotiation message.
+// IC message header common to all integration components.
 //
 typedef struct __attribute__((packed)) {
+  // Pipe flags? Unknown field that LIS does not use.
   UInt32              pipeFlags;
-  UInt32              pipeMsgs;
+  // Pipe message size? Unknown field that LIS does not use.
+  UInt32              pipeMsgSize;
 
+  // Framework version.
   VMBusVersion        frameworkVersion;
+  // Message type.
   VMBusICMessageType  type;
+  // Message version.
   VMBusVersion        msgVersion;
+  // Size of data excluding header.
   UInt16              dataSize;
+  // Return status to Hyper-V.
   HyperVStatus        status;
+  // Transaction ID. Integration components seem to disregard
+  //   the VMBus transaction ID in favor of this one.
   UInt8               transactionId;
+  // Message flags.
   UInt8               flags;
+  // Reserved.
   UInt16              reserved;
 } VMBusICMessageHeader;
 
+//
+// IC version negotiation message.
+//
 typedef struct __attribute__((packed)) {
+  // IC message header.
   VMBusICMessageHeader  header;
 
+  // Number of framework versions contained in message.
   UInt16                frameworkVersionCount;
+  // Number of message versions contained in message.
   UInt16                messageVersionCount;
+  // Reserved.
   UInt32                reserved;
+  // Array containing supported framework and message versions.
   VMBusVersion          versions[];
 } VMBusICMessageNegotiate;