jens@0: //
jens@0: //  BLIPProperties.m
jens@0: //  MYNetwork
jens@0: //
jens@0: //  Created by Jens Alfke on 5/13/08.
jens@0: //  Copyright 2008 Jens Alfke. All rights reserved.
jens@0: //
jens@0: 
jens@0: #import "BLIPProperties.h"
jens@1: #import "Logging.h"
jens@1: #import "Test.h"
jens@0: 
jens@0: 
jens@0: /** Common strings are abbreviated as single-byte strings in the packed form.
jens@0:     The ascii value of the single character minus one is the index into this table. */
jens@0: static const char* kAbbreviations[] = {
jens@0:     "Content-Type",
jens@0:     "Profile",
jens@0:     "application/octet-stream",
jens@2:     "text/plain; charset=UTF-8",
jens@0:     "text/xml",
jens@0:     "text/yaml",
jens@11:     "Channel",
jens@11:     "Error-Code",
jens@11:     "Error-Domain",
jens@0: };
jens@0: #define kNAbbreviations ((sizeof(kAbbreviations)/sizeof(const char*)))  // cannot exceed 31!
jens@0: 
jens@0: 
jens@0: 
jens@0: @interface BLIPPackedProperties : BLIPProperties
jens@0: {
jens@0:     NSData *_data;
jens@0:     int _count;
jens@0:     const char **_strings;
jens@0:     int _nStrings;
jens@0: }
jens@0: 
jens@0: @end
jens@0: 
jens@0: 
jens@0: 
jens@0: // The base class just represents an immutable empty collection.
jens@0: @implementation BLIPProperties
jens@0: 
jens@0: 
jens@0: + (BLIPProperties*) propertiesWithEncodedData: (NSData*)data usedLength: (ssize_t*)usedLength
jens@0: {
jens@0:     size_t available = data.length;
jens@0:     if( available < sizeof(UInt16) ) {
jens@0:         // Not enough available to read length:
jens@0:         *usedLength = 0;
jens@0:         return nil;
jens@0:     }
jens@0:     
jens@0:     // Read the length:
jens@0:     const char *bytes = data.bytes;
jens@8:     size_t length = NSSwapBigShortToHost( *(UInt16*)bytes ) + sizeof(UInt16);
jens@0:     if( length > available ) {
jens@0:         // Properties not complete yet.
jens@0:         *usedLength = 0;
jens@0:         return nil;
jens@0:     }
jens@0:     
jens@0:     // Complete -- try to create an object:
jens@0:     BLIPProperties *props;
jens@0:     if( length > sizeof(UInt16) )
jens@0:         props = [[[BLIPPackedProperties alloc] initWithBytes: bytes length: length] autorelease];
jens@0:     else
jens@0:         props = [BLIPProperties properties];
jens@0:     
jens@0:     *usedLength = props ?length :-1;
jens@0:     return props;
jens@0: }
jens@0: 
jens@0: 
jens@0: - (id) copyWithZone: (NSZone*)zone
jens@0: {
jens@0:     return [self retain];
jens@0: }
jens@0: 
jens@0: - (id) mutableCopyWithZone: (NSZone*)zone
jens@0: {
jens@0:     return [[BLIPMutableProperties allocWithZone: zone] initWithDictionary: self.allProperties];
jens@0: }
jens@0: 
jens@0: - (BOOL) isEqual: (id)other
jens@0: {
jens@0:     return [other isKindOfClass: [BLIPProperties class]]
jens@0:         && [self.allProperties isEqual: [other allProperties]];
jens@0: }
jens@0: 
jens@0: - (NSString*) valueOfProperty: (NSString*)prop  {return nil;}
jens@0: - (NSDictionary*) allProperties                 {return [NSDictionary dictionary];}
jens@0: - (NSUInteger) count                            {return 0;}
jens@0: - (NSUInteger) dataLength                       {return sizeof(UInt16);}
jens@0: 
jens@0: - (NSData*) encodedData
jens@0: {
jens@0:     UInt16 len = 0;
jens@0:     return [NSData dataWithBytes: &len length: sizeof(len)];
jens@0: }
jens@0: 
jens@0: 
jens@0: + (BLIPProperties*) properties
jens@0: {
jens@0:     static BLIPProperties *sEmptyInstance;
jens@0:     if( ! sEmptyInstance )
jens@0:         sEmptyInstance = [[self alloc] init];
jens@0:     return sEmptyInstance;
jens@0: }
jens@0: 
jens@0: 
jens@0: @end
jens@0: 
jens@0: 
jens@0: 
jens@0: /** Internal immutable subclass that keeps its contents in the packed data representation. */
jens@0: @implementation BLIPPackedProperties
jens@0: 
jens@0: 
jens@0: - (id) initWithBytes: (const char*)bytes length: (size_t)length
jens@0: {
jens@0:     self = [super init];
jens@0:     if (self != nil) {
jens@0:         // Copy data, then skip the length field:
jens@0:         _data = [[NSData alloc] initWithBytes: bytes length: length];
jens@0:         bytes = (const char*)_data.bytes + sizeof(UInt16);
jens@0:         length -= sizeof(UInt16);
jens@0:         
jens@0:         if( bytes[length-1]!='\0' )
jens@0:             goto fail;
jens@0: 
jens@0:         // The data consists of consecutive NUL-terminated strings, alternating key/value:
jens@0:         unsigned capacity = 0;
jens@0:         const char *end = bytes+length;
jens@0:         for( const char *str=bytes; str < end; str += strlen(str)+1, _nStrings++ ) {
jens@0:             if( _nStrings >= capacity ) {
jens@0:                 capacity = capacity ?(2*capacity) :4;
jens@0:                 _strings = realloc(_strings, capacity*sizeof(const char**));
jens@0:             }
jens@0:             UInt8 first = (UInt8)str[0];
jens@0:             if( first>'\0' && first<' ' && str[1]=='\0' ) {
jens@0:                 // Single-control-character property string is an abbreviation:
jens@0:                 if( first > kNAbbreviations )
jens@0:                     goto fail;
jens@0:                 _strings[_nStrings] = kAbbreviations[first-1];
jens@0:             } else
jens@0:                 _strings[_nStrings] = str;
jens@0:         }
jens@0:         
jens@0:         // It's illegal for the data to end with a non-NUL or for there to be an odd number of strings:
jens@0:         if( (_nStrings & 1) )
jens@0:             goto fail;
jens@0:         
jens@0:         return self;
jens@0:             
jens@0:     fail:
jens@0:         Warn(@"BLIPProperties: invalid data");
jens@0:         [self release];
jens@0:         return nil;
jens@0:     }
jens@0:     return self;
jens@0: }
jens@0: 
jens@0: 
jens@0: - (void) dealloc
jens@0: {
jens@0:     if( _strings ) free(_strings);
jens@0:     [_data release];
jens@0:     [super dealloc];
jens@0: }
jens@0: 
jens@0: - (id) copyWithZone: (NSZone*)zone
jens@0: {
jens@0:     return [self retain];
jens@0: }
jens@0: 
jens@0: - (id) mutableCopyWithZone: (NSZone*)zone
jens@0: {
jens@0:     return [[BLIPMutableProperties allocWithZone: zone] initWithDictionary: self.allProperties];
jens@0: }
jens@0: 
jens@0: 
jens@0: - (NSString*) valueOfProperty: (NSString*)prop
jens@0: {
jens@0:     const char *propStr = [prop UTF8String];
jens@0:     Assert(propStr);
jens@0:     // Search in reverse order so that later values will take precedence over earlier ones.
jens@0:     for( int i=_nStrings-2; i>=0; i-=2 ) {
jens@0:         if( strcmp(propStr, _strings[i]) == 0 )
jens@0:             return [NSString stringWithUTF8String: _strings[i+1]];
jens@0:     }
jens@0:     return nil;
jens@0: }
jens@0: 
jens@0: 
jens@0: - (NSDictionary*) allProperties
jens@0: {
jens@0:     NSMutableDictionary *props = [NSMutableDictionary dictionaryWithCapacity: _nStrings/2];
jens@0:     // Add values in forward order so that later ones will overwrite (take precedence over)
jens@0:     // earlier ones, which matches the behavior of -valueOfProperty.
jens@0:     // (However, note that unlike -valueOfProperty, this dictionary is case-sensitive!)
jens@0:     for( int i=0; i<_nStrings; i+=2 ) {
jens@0:         NSString *key = [[NSString alloc] initWithUTF8String: _strings[i]];
jens@0:         NSString *value = [[NSString alloc] initWithUTF8String: _strings[i+1]];
jens@0:         if( key && value )
jens@0:             [props setObject: value forKey: key];
jens@0:         [key release];
jens@0:         [value release];
jens@0:     }
jens@0:     return props;
jens@0: }
jens@0: 
jens@0: 
jens@0: - (NSUInteger) count        {return _nStrings/2;}
jens@0: - (NSData*) encodedData            {return _data;}
jens@0: - (NSUInteger) dataLength   {return _data.length;}
jens@0: 
jens@0: 
jens@0: @end
jens@0: 
jens@0: 
jens@0: 
jens@0: /** Mutable subclass that stores its properties in an NSMutableDictionary. */
jens@0: @implementation BLIPMutableProperties
jens@0: 
jens@0: 
jens@0: + (BLIPProperties*) properties
jens@0: {
jens@0:     return [[self alloc] initWithDictionary: nil];
jens@0: }
jens@0: 
jens@0: - (id) init
jens@0: {
jens@0:     self = [super init];
jens@0:     if (self != nil) {
jens@0:         _properties = [[NSMutableDictionary alloc] init];
jens@0:     }
jens@0:     return self;
jens@0: }
jens@0: 
jens@0: - (id) initWithDictionary: (NSDictionary*)dict
jens@0: {
jens@0:     self = [super init];
jens@0:     if (self != nil) {
jens@0:         _properties = dict ?[dict mutableCopy] :[[NSMutableDictionary alloc] init];
jens@0:     }
jens@0:     return self;
jens@0: }
jens@0: 
jens@0: - (id) initWithProperties: (BLIPProperties*)properties
jens@0: {
jens@0:     return [self initWithDictionary: [properties allProperties]];
jens@0: }
jens@0: 
jens@0: - (void) dealloc
jens@0: {
jens@0:     [_properties release];
jens@0:     [super dealloc];
jens@0: }
jens@0: 
jens@0: - (id) copyWithZone: (NSZone*)zone
jens@0: {
jens@0:     ssize_t usedLength;
jens@0:     BLIPProperties *copy = [BLIPProperties propertiesWithEncodedData: self.encodedData usedLength: &usedLength];
jens@0:     Assert(copy);
jens@0:     return [copy retain];
jens@0: }
jens@0: 
jens@0: 
jens@0: - (NSString*) valueOfProperty: (NSString*)prop
jens@0: {
jens@0:     return [_properties objectForKey: prop];
jens@0: }
jens@0: 
jens@0: - (NSDictionary*) allProperties
jens@0: {
jens@0:     return _properties;
jens@0: }
jens@0: 
jens@0: - (NSUInteger) count        {return _properties.count;}
jens@0: 
jens@0: 
jens@0: static void appendStr( NSMutableData *data, NSString *str ) {
jens@0:     const char *utf8 = [str UTF8String];
jens@0:     size_t size = strlen(utf8)+1;
jens@0:     for( int i=0; i<kNAbbreviations; i++ )
jens@0:         if( memcmp(utf8,kAbbreviations[i],size)==0 ) {
jens@0:             const UInt8 abbrev[2] = {i+1,0};
jens@0:             [data appendBytes: &abbrev length: 2];
jens@0:             return;
jens@0:         }
jens@0:     [data appendBytes: utf8 length: size];
jens@0: }
jens@0: 
jens@0: - (NSData*) encodedData
jens@0: {
jens@0:     NSMutableData *data = [NSMutableData dataWithCapacity: 16*_properties.count];
jens@0:     [data setLength: sizeof(UInt16)]; // leave room for length
jens@0:     for( NSString *name in _properties ) {
jens@0:         appendStr(data,name);
jens@0:         appendStr(data,[_properties objectForKey: name]);
jens@0:     }
jens@0:     
jens@0:     NSUInteger length = data.length - sizeof(UInt16);
jens@0:     if( length > 0xFFFF )
jens@0:         return nil;
jens@8:     *(UInt16*)[data mutableBytes] = NSSwapHostShortToBig((UInt16)length);
jens@0:     return data;
jens@0: }
jens@0: 
jens@0:     
jens@0: - (void) setValue: (NSString*)value ofProperty: (NSString*)prop
jens@0: {
jens@0:     Assert(prop.length>0);
jens@0:     if( value )
jens@0:         [_properties setObject: value forKey: prop];
jens@0:     else
jens@0:         [_properties removeObjectForKey: prop];
jens@0: }
jens@0: 
jens@0: 
jens@0: - (void) setAllProperties: (NSDictionary*)properties
jens@0: {
jens@0:     if( properties.count ) {
jens@0:         for( id key in properties ) {
jens@0:             Assert([key isKindOfClass: [NSString class]]);
jens@0:             Assert([key length] > 0);
jens@0:             Assert([[properties objectForKey: key] isKindOfClass: [NSString class]]);
jens@0:         }
jens@0:         [_properties setDictionary: properties];
jens@0:     } else
jens@0:         [_properties removeAllObjects];
jens@0: }
jens@0: 
jens@0: 
jens@0: @end
jens@0: 
jens@0: 
jens@0: 
jens@0: 
jens@0: TestCase(BLIPProperties) {
jens@0:     BLIPProperties *props;
jens@0:     
jens@0:     props = [BLIPProperties properties];
jens@0:     CAssert(props);
jens@0:     CAssertEq(props.count,0);
jens@0:     Log(@"Empty properties:\n%@", props.allProperties);
jens@0:     NSData *data = props.encodedData;
jens@0:     Log(@"As data: %@", data);
jens@0:     CAssertEqual(data,[NSMutableData dataWithLength: 2]);
jens@0:     
jens@0:     BLIPMutableProperties *mprops = [props mutableCopy];
jens@0:     Log(@"Mutable copy:\n%@", mprops.allProperties);
jens@0:     data = mprops.encodedData;
jens@0:     Log(@"As data: %@", data);
jens@0:     CAssertEqual(data,[NSMutableData dataWithLength: 2]);
jens@0:     
jens@0:     ssize_t used;
jens@0:     props = [BLIPProperties propertiesWithEncodedData: data usedLength: &used];
jens@0:     CAssertEq(used,data.length);
jens@0:     CAssertEqual(props,mprops);
jens@0:     
jens@0:     [mprops setValue: @"Jens" ofProperty: @"First-Name"];
jens@0:     [mprops setValue: @"Alfke" ofProperty: @"Last-Name"];
jens@0:     [mprops setValue: @"" ofProperty: @"Empty-String"];
jens@0:     [mprops setValue: @"Z" ofProperty: @"A"];
jens@0:     Log(@"With properties:\n%@", mprops.allProperties);
jens@0:     data = mprops.encodedData;
jens@0:     Log(@"As data: %@", data);
jens@0:     
jens@0:     for( unsigned len=0; len<data.length; len++ ) {
jens@0:         props = [BLIPProperties propertiesWithEncodedData: [data subdataWithRange: NSMakeRange(0,len)]
jens@0:                                                                 usedLength: &used];
jens@0:         CAssertEq(props,nil);
jens@0:         CAssertEq(used,0);
jens@0:     }
jens@0:     props = [BLIPProperties propertiesWithEncodedData: data usedLength: &used];
jens@0:     CAssertEq(used,data.length);
jens@0:     Log(@"Read back in:\n%@",props.allProperties);
jens@0:     CAssertEqual(props,mprops);
jens@0:     
jens@0:     NSDictionary *all = mprops.allProperties;
jens@0:     for( NSString *prop in all )
jens@0:         CAssertEqual([props valueOfProperty: prop],[all objectForKey: prop]);
jens@0: }
jens@0: 
jens@0: 
jens@0: /*
jens@0:  Copyright (c) 2008, Jens Alfke <jens@mooseyard.com>. All rights reserved.
jens@0:  
jens@0:  Redistribution and use in source and binary forms, with or without modification, are permitted
jens@0:  provided that the following conditions are met:
jens@0:  
jens@0:  * Redistributions of source code must retain the above copyright notice, this list of conditions
jens@0:  and the following disclaimer.
jens@0:  * Redistributions in binary form must reproduce the above copyright notice, this list of conditions
jens@0:  and the following disclaimer in the documentation and/or other materials provided with the
jens@0:  distribution.
jens@0:  
jens@0:  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR
jens@0:  IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 
jens@0:  FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRI-
jens@0:  BUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
jens@0:  (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 
jens@0:   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
jens@0:  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 
jens@0:  THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
jens@0:  */