Additions for support of efficient NSArchiver/NSUnarchiver while permiting

ffective subclassing.


git-svn-id: svn+ssh://svn.gna.org/svn/gnustep/libs/base/trunk@3107 72102866-910b-0410-8b05-ffd578937521

Headers/gnustep/base/NSData.h

@@ -94,6 +94,16 @@
 + (id) dataWithShmID: (int)anID length: (unsigned) length;
 + (id) dataWithSharedBytes: (const void*)bytes length: (unsigned) length;
 + (id) dataWithStaticBytes: (const void*)bytes length: (unsigned) length;
+
+/*
+ *	-deserializeTypeTagAtCursor:
+ *	-deserializeCrossRefAtCursor:
+ *	These methods are provided in order to give the GNUstep version of
+ *	NSUnarchiver maximum possible performance.
+ */
+- (unsigned char) deserializeTypeTagAtCursor: (unsigned*)cursor;
+- (unsigned) deserializeCrossRefAtCursor: (unsigned*)cursor;
+
 /*
  *	-initWithBytesNoCopy:length:fromZone:
  *	The GNUstep designated initialiser for normal data objects - lets
@@ -169,9 +179,24 @@
 @end
 
 @interface NSMutableData (GNUstepExtensions)
+/*
+ *	Capacity management - GNUstep gives you control over the size of
+ *	the data buffer as well as the 'length' of valid data in it.
+ */
 - (unsigned int) capacity;
 - (id) setCapacity: (unsigned int)newCapacity;
-- (int) shmID;
+
+- (int) shmID;	/* Shared memory ID for data buffer (if any)	*/
+
+/*
+ *	-serializeTypeTag:
+ *	-serializeCrossRef:
+ *	These methods are provided in order to give the GNUstep version of
+ *	NSArchiver maximum possible performance.
+ */
+- (void) serializeTypeTag: (unsigned char)tag;
+- (void) serializeCrossRef: (unsigned)xref;
+
 @end
 
 /*

Source/NSData.m

@@ -934,6 +934,28 @@ failure:
   [self subclassResponsibility: _cmd];
 }
 
+- (unsigned char) deserializeTypeTagAtCursor: (unsigned*)cursor
+{
+    unsigned char	result;
+
+    [self deserializeDataAt: (void*)&result
+		 ofObjCType: @encode(unsigned char) 
+		   atCursor: cursor
+		    context: nil];
+    return result;
+}
+
+- (unsigned) deserializeCrossRefAtCursor: (unsigned*)cursor
+{
+    unsigned result;
+
+    [self deserializeDataAt: (void*)&result
+		 ofObjCType: @encode(unsigned) 
+		   atCursor: cursor
+		    context: nil];
+    return result;
+}
+
 - (void*) relinquishAllocatedBytes
 {
     return [self relinquishAllocatedBytesFromZone: 0];
@@ -1350,6 +1372,20 @@ failure:
 {
   return -1;
 }
+
+- (void) serializeTypeTag: (unsigned char)tag
+{
+    [self serializeDataAt: (void*)&tag
+	       ofObjCType: @encode(unsigned char)
+		  context: nil];
+}
+
+- (void) serializeCrossRef: (unsigned)xref
+{
+    [self serializeDataAt: (void*)&xref
+	       ofObjCType: @encode(unsigned)
+		  context: nil];
+}
 @end
 
 
@@ -1671,6 +1707,23 @@ getBytes(void* dst, void* src, unsigned len, unsigned limit, unsigned *pos)
     }
 }
 
+- (unsigned char) deserializeTypeTagAtCursor: (unsigned*)cursor
+{
+    if (*cursor >= length) {
+	[NSException raise: NSRangeException
+		    format: @"Range: (%u, 1) Size: %d", *cursor, length];
+    }
+    return ((unsigned char*)bytes)[(*cursor)++];
+}
+
+- (unsigned) deserializeCrossRefAtCursor: (unsigned*)cursor
+{
+    unsigned ni;
+
+    getBytes((void*)&ni, bytes, sizeof(ni), length, cursor);
+    return (unsigned)NSSwapBigIntToHost(ni);
+}
+
 @end
 
 @implementation	NSDataMalloc
@@ -2406,6 +2459,24 @@ getBytes(void* dst, void* src, unsigned len, unsigned limit, unsigned *pos)
     }
 }
 
+- (void) serializeTypeTag: (unsigned char)tag
+{
+    if (length == capacity) {
+	[self _grow: length + 1];
+    }
+    ((unsigned char*)bytes)[length++] = tag;
+}
+
+- (void) serializeCrossRef: (unsigned)xref
+{
+    if (length + sizeof(unsigned) >= capacity) {
+	[self _grow: length + sizeof(unsigned)];
+    }
+    xref = NSSwapHostIntToBig(xref);
+    memcpy(bytes+length, &xref, sizeof(unsigned));
+    length += sizeof(unsigned);
+}
+
 - (id) setCapacity: (unsigned)size
 {
     if (size != capacity) {