IPAddress.h
author Jens Alfke <jens@mooseyard.com>
Fri May 30 13:54:38 2008 -0700 (2008-05-30)
changeset 9 980beba83fb7
parent 0 9d67172bb323
child 26 cb9cdf247239
permissions -rw-r--r--
Fixed a serious bug - a race condition where a data buffer in the writer's queue could be dealloced (not the NSData, but its bytes themselves) before the writer sent it, resulting in an EFAULT error.
     1 //
     2 //  IPAddress.h
     3 //  MYNetwork
     4 //
     5 //  Created by Jens Alfke on 1/4/08.
     6 //  Copyright 2008 Jens Alfke. All rights reserved.
     7 //
     8 
     9 #import <Foundation/Foundation.h>
    10 
    11 
    12 /** Represents an Internet Protocol address and port number (similar to a sockaddr_in).
    13     IPAddress itself only remembers the raw 32-bit IPv4 address; the subclass HostAddress
    14     also remembers the DNS host-name. */
    15 @interface IPAddress : NSObject <NSCoding, NSCopying>
    16 {
    17     UInt32 _ipv4;       // In network byte order (big-endian), just like struct in_addr
    18     UInt16 _port;       // native byte order
    19 }
    20 
    21 /** Initializes an IPAddress from a host name (which may be a DNS name or dotted-quad numeric form)
    22     and port number.
    23     If the hostname is not in dotted-quad form, an instance of the subclass HostAddress will
    24     be returned instead. */
    25 - (id) initWithHostname: (NSString*)hostname port: (UInt16)port;
    26 
    27 /** Initializes an IPAddress from a raw IPv4 address (in network byte order, i.e. big-endian)
    28     and port number (in native byte order) */
    29 - (id) initWithIPv4: (UInt32)ipv4 port: (UInt16)port;
    30 
    31 /** Initializes an IPAddress from a raw IPv4 address (in network byte order, i.e. big-endian).
    32     The port number defaults to zero. */
    33 - (id) initWithIPv4: (UInt32)ipv4;
    34 
    35 /** Initializes an IPAddress from a BSD struct sockaddr. */
    36 - (id) initWithSockAddr: (const struct sockaddr*)sockaddr;
    37 
    38 /** Returns the IP address of this host (with a port number of zero).
    39     If multiple network interfaces are active, the main one's address is returned. */
    40 + (IPAddress*) localAddress;
    41 
    42 /** Returns the address of the peer that an open socket is connected to.
    43     (This calls getpeername.) */
    44 + (IPAddress*) addressOfSocket: (CFSocketNativeHandle)socket;
    45 
    46 /** Returns YES if the two objects have the same IP address, ignoring port numbers. */
    47 - (BOOL) isSameHost: (IPAddress*)addr;
    48 
    49 /** The raw IPv4 address, in network (big-endian) byte order. */
    50 @property (readonly) UInt32 ipv4;               // raw address in network byte order
    51 
    52 /** The address as a dotted-quad string, e.g. @"10.0.1.1". */
    53 @property (readonly) NSString* ipv4name;
    54 
    55 /** The address as a DNS hostname or else a dotted-quad string.
    56     (IPAddress itself always returns dotted-quad; HostAddress returns the hostname it was
    57     initialized with.) */
    58 @property (readonly) NSString* hostname;        // dotted-quad string, or DNS name if I am a HostAddress
    59 
    60 /** The port number, or zero if none was specified, in native byte order. */
    61 @property (readonly) UInt16 port;
    62 
    63 /** Is this IP address in a designated private/local address range, such as 10.0.1.X?
    64     If so, the address is not globally meaningful outside of the local subnet. */
    65 @property (readonly) BOOL isPrivate;            // In a private/local addr range like 10.0.1.X?
    66 @end
    67 
    68 
    69 
    70 /** A subclass of IPAddress that remembers the DNS hostname instead of a raw address.
    71     An instance of HostAddress looks up its ipv4 address on the fly by calling gethostbyname. */
    72 @interface HostAddress : IPAddress
    73 {
    74     NSString *_hostname;
    75 }
    76 
    77 - (id) initWithHostname: (NSString*)hostname port: (UInt16)port;
    78 
    79 @end
    80 
    81 
    82 
    83 /** An IPAddress that can keep track of statistics on when it was last sucessfully used
    84     and the number of successful attempts. This is useful when keeping a cache of recent
    85     addresses for a peer that doesn't have a stable address. */
    86 @interface RecentAddress : IPAddress
    87 {
    88     CFAbsoluteTime _lastSuccess;
    89     UInt32 _successes;
    90 }
    91 
    92 /** Initializes a RecentAddress from an IPAddress. (You can also initialize RecentAddress using
    93     any inherited initializer method.) */
    94 - (id) initWithIPAddress: (IPAddress*)addr;
    95 
    96 /** The absolute time that -noteSuccess or -noteSeen was last called. */
    97 @property (readonly) CFAbsoluteTime lastSuccess;
    98 
    99 /** The number of times that -noteSuccess has been called. */
   100 @property (readonly) UInt32 successes;
   101 
   102 /** Call this to indicate that the address was successfully used to connect to the desired peer.
   103     Returns YES if the state of the object has changed and it should be re-archived. */
   104 - (BOOL) noteSuccess;
   105 
   106 /** Call this to indicate that you have received evidence that this address is currently being
   107     used by this peer. Unlike -noteSuccess it doesn't increment -successes, and only returns
   108     YES (to indicate a persistent change) once every 18 hours (to avoid making the client
   109     save its cache too often.) */
   110 - (BOOL) noteSeen;
   111 
   112 @end