THRIFT-2180 Integer types issues in Cocoa lib on ARM64

CLient: Cocoa
Patch: Jeremy W. Sherman
This closes #372
diff --git a/lib/cocoa/src/transport/THTTPClient.m b/lib/cocoa/src/transport/THTTPClient.m
index 5617d45..169927c 100644
--- a/lib/cocoa/src/transport/THTTPClient.m
+++ b/lib/cocoa/src/transport/THTTPClient.m
@@ -102,20 +102,20 @@
 }
 
 
-- (int) readAll: (uint8_t *) buf offset: (int) off length: (int) len
+- (size_t) readAll: (uint8_t *) buf offset: (size_t) offset length: (size_t) length
 {
   NSRange r;
   r.location = mResponseDataOffset;
-  r.length = len;
+  r.length = length;
 
-  [mResponseData getBytes: buf+off range: r];
-  mResponseDataOffset += len;
+  [mResponseData getBytes: buf+offset range: r];
+  mResponseDataOffset += length;
 
-  return len;
+  return length;
 }
 
 
-- (void) write: (const uint8_t *) data offset: (unsigned int) offset length: (unsigned int) length
+- (void) write: (const uint8_t *) data offset: (size_t) offset length: (size_t) length
 {
   [mRequestData appendBytes: data+offset length: length];
 }
@@ -147,8 +147,8 @@
   NSHTTPURLResponse * httpResponse = (NSHTTPURLResponse *) response;
   if ([httpResponse statusCode] != 200) {
     @throw [TTransportException exceptionWithName: @"TTransportException"
-                                           reason: [NSString stringWithFormat: @"Bad response from HTTP server: %d",
-                                                    [httpResponse statusCode]]];
+                                           reason: [NSString stringWithFormat: @"Bad response from HTTP server: %ld",
+                                                    (long)[httpResponse statusCode]]];
   }
 
   // phew!