Add NSData_SA_NSDataExtensions

.gitignore

@@ -28,6 +28,5 @@ xcuserdata
 *.ipa
 
 libirc*
-NSData*
 
 *~

NSData+SA_NSDataExtensions/NSData+SA_NSDataExtensions.h

@@ -0,0 +1,90 @@
+//
+//  NSData+SA_NSDataExtensions.h
+//
+//  Copyright (c) 2015 Said Achmiz.
+//
+//	Permission is hereby granted, free of charge, to any person obtaining a copy
+//	of this software and associated documentation files (the "Software"), to deal
+//	in the Software without restriction, including without limitation the rights
+//	to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+//	copies of the Software, and to permit persons to whom the Software is
+//	furnished to do so, subject to the following conditions:
+//
+//	The above copyright notice and this permission notice shall be included in all
+//	copies or substantial portions of the Software.
+//
+//	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//	IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//	FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//	AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//	LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//	OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//	SOFTWARE.
+
+#import <Foundation/Foundation.h>
+
+/** \category NSData+SA_NSDataExtensions
+ *	@brief Adds several utility methods to NSData.
+ */
+@interface NSData (SA_NSDataExtensions)
+
+//	NOTE on stripping nulls from the ends of byte arrays.
+//
+//	If you strip a null from the end of an array which is something other than
+//	a null-terminated C string (such as, for example, the bytes representing a
+//	UTF-16 string), and thereby cause yourself difficulties, you have only
+//	yourself to blame. Be sure that you know what your NSData objects are 
+//	supposed to contain!
+
+/**	Returns YES if the last byte of the stored data is null, NO otherwise.
+ */
+@property (readonly, getter=isNullTerminated) BOOL nullTerminated;
+
+/** Returns the stored bytes as a null-terminated C string (byte array).
+	
+	If the stored data is already null-terminated, the returned pointer will
+	be a pointer to the bytes managed by the receiver. If it is not already
+	null-terminated, the returned pointer will point to bytes managed by a 
+	copy of the receiver (and the bytes of the copy will be null-terminated).
+ */
+@property (readonly) const char *SA_terminatedCString;
+
+/**	Returns data containing the stored bytes as a null-terminated C string
+	(byte array).
+	
+	If the stored data is already null-terminated, this method simply returns
+	the receiver. If it is not already null-terminated, this method returns a 
+	reference to a fresh copy of the receiver (a copy that contains a 
+	null-terminated byte array, of course).
+ */
+@property (readonly) NSData *SA_dataWithTerminatedCString;
+
+/**	Returns the stored bytes as an non-null-terminated byte array.
+ 
+	If the stored data was not null-terminated to begin with, the returned 
+	pointer will be a pointer to the bytes managed by the receiver. If the 
+	stored data was null-terminated, the returned pointer will point to bytes
+	managed by a copy of the receiver (and the bytes of the copy will not be 
+	null-terminated; but see NOTE).
+ 
+	NOTE: If the receiver's *last* byte is null, the bytes pointed to by the
+	returned pointer will have that null stripped; but if there are any more
+	null bytes prior to that last null, they will remain untouched!
+ */
+@property (readonly) const char *SA_unterminatedByteString;
+
+/**	Returns data containing the stored bytes as a non-null-terminated byte 
+	array.
+ 
+	If the stored data was not null-terminated to begin with, this method simply
+	returns the receiver. If the stored data was null-terminated, this method 
+	returns a reference to a fresh copy of the receiver (a copy that contains a
+	non-null-terminated byte array, of course; but see NOTE).
+ 
+	NOTE: If the receiver's *last* byte is null, the bytes managed by the
+	returned object will have that null stripped; but if there are any more
+	null bytes prior to that last null, they will remain untouched!
+ */
+@property (readonly) NSData *SA_dataWithUnterminatedByteString;
+
+@end

NSData+SA_NSDataExtensions/NSData+SA_NSDataExtensions.m

@@ -0,0 +1,78 @@
+//
+//  NSData+SA_NSDataExtensions.h
+//
+//  Copyright (c) 2015 Said Achmiz.
+//
+//	Permission is hereby granted, free of charge, to any person obtaining a copy
+//	of this software and associated documentation files (the "Software"), to deal
+//	in the Software without restriction, including without limitation the rights
+//	to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+//	copies of the Software, and to permit persons to whom the Software is
+//	furnished to do so, subject to the following conditions:
+//
+//	The above copyright notice and this permission notice shall be included in all
+//	copies or substantial portions of the Software.
+//
+//	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+//	IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+//	FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+//	AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+//	LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+//	OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+//	SOFTWARE.
+
+#import "NSData+SA_NSDataExtensions.h"
+
+@implementation NSData (SA_NSDataExtensions)
+
+-(BOOL)isNullTerminated
+{
+	return (((char*) self.bytes)[self.length - 1] == '\0');
+}
+
+-(const char *)SA_terminatedCString
+{
+	return self.SA_dataWithTerminatedCString.bytes;
+}
+
+-(NSData *)SA_dataWithTerminatedCString
+{
+	if(self.length == 0)
+	{
+		return [NSData dataWithBytes:"\0" length:1];
+	}
+	else if(self.isNullTerminated)
+	{
+		return self;
+	}
+	else
+	{
+		char* terminated_string_buffer = malloc(self.length + 1);
+		[self getBytes:terminated_string_buffer length:self.length];
+		terminated_string_buffer[self.length] = '\0';
+		
+		return [NSData dataWithBytesNoCopy:terminated_string_buffer length:self.length + 1 freeWhenDone:YES];
+	}
+}
+
+-(const char *)SA_unterminatedByteString
+{
+	return self.SA_dataWithUnterminatedByteString.bytes;
+}
+
+-(NSData *)SA_dataWithUnterminatedByteString
+{
+	if(self.length == 0 || self.isNullTerminated == NO)
+	{
+		return self;
+	}
+	else
+	{
+		char* unterminated_string_buffer = malloc(self.length - 1);
+		[self getBytes:unterminated_string_buffer length:self.length - 1];
+		
+		return [NSData dataWithBytesNoCopy:unterminated_string_buffer length:self.length - 1 freeWhenDone:YES];
+	}
+}
+
+@end