diff -r 000000000000 -r 88d7e2455a7f GoogleToolboxSubset/GTMNSData+zlib.m
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/GoogleToolboxSubset/GTMNSData+zlib.m	Sat Mar 28 09:39:31 2009 -0700
@@ -0,0 +1,267 @@
+//
+//  GTMNSData+zlib.m
+//
+//  Copyright 2007-2008 Google Inc.
+//
+//  Licensed under the Apache License, Version 2.0 (the "License"); you may not
+//  use this file except in compliance with the License.  You may obtain a copy
+//  of the License at
+// 
+//  http://www.apache.org/licenses/LICENSE-2.0
+// 
+//  Unless required by applicable law or agreed to in writing, software
+//  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+//  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.  See the
+//  License for the specific language governing permissions and limitations under
+//  the License.
+//
+
+#import "GTMNSData+zlib.h"
+#import <zlib.h>
+#import "GTMDefines.h"
+
+#define kChunkSize 1024
+
+@interface NSData (GTMZlibAdditionsPrivate)
++ (NSData *)gtm_dataByCompressingBytes:(const void *)bytes
+                                length:(NSUInteger)length
+                      compressionLevel:(int)level
+                               useGzip:(BOOL)useGzip;
+@end
+
+@implementation NSData (GTMZlibAdditionsPrivate)
++ (NSData *)gtm_dataByCompressingBytes:(const void *)bytes
+                                length:(NSUInteger)length
+                      compressionLevel:(int)level
+                               useGzip:(BOOL)useGzip {
+  if (!bytes || !length) {
+    return nil;
+  }
+  
+  // TODO: support 64bit inputs
+  // avail_in is a uInt, so if length > UINT_MAX we actually need to loop
+  // feeding the data until we've gotten it all in.  not supporting this
+  // at the moment.
+  _GTMDevAssert(length <= UINT_MAX, @"Currently don't support >32bit lengths");
+
+  if (level == Z_DEFAULT_COMPRESSION) {
+    // the default value is actually outside the range, so we have to let it
+    // through specifically.
+  } else if (level < Z_BEST_SPEED) {
+    level = Z_BEST_SPEED;
+  } else if (level > Z_BEST_COMPRESSION) {
+    level = Z_BEST_COMPRESSION;
+  }
+
+  z_stream strm;
+  bzero(&strm, sizeof(z_stream));
+
+  int windowBits = 15; // the default
+  int memLevel = 8; // the default
+  if (useGzip) {
+    windowBits += 16; // enable gzip header instead of zlib header
+  }
+  int retCode;
+  if ((retCode = deflateInit2(&strm, level, Z_DEFLATED, windowBits,
+                              memLevel, Z_DEFAULT_STRATEGY)) != Z_OK) {
+    // COV_NF_START - no real way to force this in a unittest (we guard all args)
+    _GTMDevLog(@"Failed to init for deflate w/ level %d, error %d",
+               level, retCode);
+    return nil;
+    // COV_NF_END
+  }
+
+  // hint the size at 1/4 the input size
+  NSMutableData *result = [NSMutableData dataWithCapacity:(length/4)];
+  unsigned char output[kChunkSize];
+
+  // setup the input
+  strm.avail_in = (unsigned int)length;
+  strm.next_in = (unsigned char*)bytes;
+
+  // loop to collect the data
+  do {
+    // update what we're passing in
+    strm.avail_out = kChunkSize;
+    strm.next_out = output;
+    retCode = deflate(&strm, Z_FINISH);
+    if ((retCode != Z_OK) && (retCode != Z_STREAM_END)) {
+      // COV_NF_START - no real way to force this in a unittest
+      // (in inflate, we can feed bogus/truncated data to test, but an error
+      // here would be some internal issue w/in zlib, and there isn't any real
+      // way to test it)
+      _GTMDevLog(@"Error trying to deflate some of the payload, error %d",
+                 retCode);
+      deflateEnd(&strm);
+      return nil;
+      // COV_NF_END
+    }
+    // collect what we got
+    unsigned gotBack = kChunkSize - strm.avail_out;
+    if (gotBack > 0) {
+      [result appendBytes:output length:gotBack];
+    }
+
+  } while (retCode == Z_OK);
+
+  // if the loop exits, we used all input and the stream ended
+  _GTMDevAssert(strm.avail_in == 0,
+                @"thought we finished deflate w/o using all input, %u bytes left",
+                strm.avail_in);
+  _GTMDevAssert(retCode == Z_STREAM_END,
+                @"thought we finished deflate w/o getting a result of stream end, code %d",
+                retCode);
+
+  // clean up
+  deflateEnd(&strm);
+
+  return result;
+} // gtm_dataByCompressingBytes:length:compressionLevel:useGzip:
+  
+
+@end
+
+
+@implementation NSData (GTMZLibAdditions)
+
++ (NSData *)gtm_dataByGzippingBytes:(const void *)bytes
+                             length:(NSUInteger)length {
+  return [self gtm_dataByCompressingBytes:bytes
+                                   length:length
+                         compressionLevel:Z_DEFAULT_COMPRESSION
+                                  useGzip:YES];
+} // gtm_dataByGzippingBytes:length:
+
++ (NSData *)gtm_dataByGzippingData:(NSData *)data {
+  return [self gtm_dataByCompressingBytes:[data bytes]
+                                   length:[data length]
+                         compressionLevel:Z_DEFAULT_COMPRESSION
+                                  useGzip:YES];
+} // gtm_dataByGzippingData:
+
++ (NSData *)gtm_dataByGzippingBytes:(const void *)bytes
+                             length:(NSUInteger)length
+                   compressionLevel:(int)level {
+  return [self gtm_dataByCompressingBytes:bytes
+                                   length:length
+                         compressionLevel:level
+                                  useGzip:YES];
+} // gtm_dataByGzippingBytes:length:level:
+
++ (NSData *)gtm_dataByGzippingData:(NSData *)data
+                  compressionLevel:(int)level {
+  return [self gtm_dataByCompressingBytes:[data bytes]
+                                   length:[data length]
+                         compressionLevel:level
+                                  useGzip:YES];
+} // gtm_dataByGzippingData:level:
+
++ (NSData *)gtm_dataByDeflatingBytes:(const void *)bytes
+                              length:(NSUInteger)length {
+  return [self gtm_dataByCompressingBytes:bytes
+                                   length:length
+                         compressionLevel:Z_DEFAULT_COMPRESSION
+                                  useGzip:NO];
+} // gtm_dataByDeflatingBytes:length:
+
++ (NSData *)gtm_dataByDeflatingData:(NSData *)data {
+  return [self gtm_dataByCompressingBytes:[data bytes]
+                                   length:[data length]
+                         compressionLevel:Z_DEFAULT_COMPRESSION
+                                  useGzip:NO];
+} // gtm_dataByDeflatingData:
+
++ (NSData *)gtm_dataByDeflatingBytes:(const void *)bytes
+                              length:(NSUInteger)length
+                    compressionLevel:(int)level {
+  return [self gtm_dataByCompressingBytes:bytes
+                                   length:length
+                         compressionLevel:level
+                                  useGzip:NO];
+} // gtm_dataByDeflatingBytes:length:level:
+
++ (NSData *)gtm_dataByDeflatingData:(NSData *)data
+                   compressionLevel:(int)level {
+  return [self gtm_dataByCompressingBytes:[data bytes]
+                                   length:[data length]
+                         compressionLevel:level
+                                  useGzip:NO];
+} // gtm_dataByDeflatingData:level:
+
++ (NSData *)gtm_dataByInflatingBytes:(const void *)bytes
+                              length:(NSUInteger)length {
+  if (!bytes || !length) {
+    return nil;
+  }
+  
+  // TODO: support 64bit inputs
+  // avail_in is a uInt, so if length > UINT_MAX we actually need to loop
+  // feeding the data until we've gotten it all in.  not supporting this
+  // at the moment.
+  _GTMDevAssert(length <= UINT_MAX, @"Currently don't support >32bit lengths");
+
+  z_stream strm;
+  bzero(&strm, sizeof(z_stream));
+
+  // setup the input
+  strm.avail_in = (unsigned int)length;
+  strm.next_in = (unsigned char*)bytes;
+
+  int windowBits = 15; // 15 to enable any window size
+  windowBits += 32; // and +32 to enable zlib or gzip header detection.
+  int retCode;
+  if ((retCode = inflateInit2(&strm, windowBits)) != Z_OK) {
+    // COV_NF_START - no real way to force this in a unittest (we guard all args)
+    _GTMDevLog(@"Failed to init for inflate, error %d", retCode);
+    return nil;
+    // COV_NF_END
+  }
+
+  // hint the size at 4x the input size
+  NSMutableData *result = [NSMutableData dataWithCapacity:(length*4)];
+  unsigned char output[kChunkSize];
+
+  // loop to collect the data
+  do {
+    // update what we're passing in
+    strm.avail_out = kChunkSize;
+    strm.next_out = output;
+    retCode = inflate(&strm, Z_NO_FLUSH);
+    if ((retCode != Z_OK) && (retCode != Z_STREAM_END)) {
+      _GTMDevLog(@"Error trying to inflate some of the payload, error %d",
+                 retCode);
+      inflateEnd(&strm);
+      return nil;
+    }
+    // collect what we got
+    unsigned gotBack = kChunkSize - strm.avail_out;
+    if (gotBack > 0) {
+      [result appendBytes:output length:gotBack];
+    }
+
+  } while (retCode == Z_OK);
+
+  // make sure there wasn't more data tacked onto the end of a valid compressed
+  // stream.
+  if (strm.avail_in != 0) {
+    _GTMDevLog(@"thought we finished inflate w/o using all input, %u bytes left",
+               strm.avail_in);
+    result = nil;
+  }
+  // the only way out of the loop was by hitting the end of the stream
+  _GTMDevAssert(retCode == Z_STREAM_END,
+                @"thought we finished inflate w/o getting a result of stream end, code %d",
+                retCode);
+
+  // clean up
+  inflateEnd(&strm);
+
+  return result;
+} // gtm_dataByInflatingBytes:length:
+
++ (NSData *)gtm_dataByInflatingData:(NSData *)data {
+  return [self gtm_dataByInflatingBytes:[data bytes]
+                                 length:[data length]];
+} // gtm_dataByInflatingData:
+
+@end