methods/rfc2553emu.cc

   1 // -*- mode: cpp; mode: fold -*-
   2 // Description                                                          /*{{{*/
   3 // $Id: rfc2553emu.cc,v 1.1 1999/05/25 05:56:24 jgg Exp $
   4 /* ######################################################################
   5
   6    RFC 2553 Emulation - Provides emulation for RFC 2553 getaddrinfo,
   7                         freeaddrinfo and getnameinfo
   8
   9    Originally written by Jason Gunthorpe <jgg@debian.org> and placed into
  10    the Public Domain, do with it what you will.
  11
  12    ##################################################################### */
  13                                                                         /*}}}*/
  14 #include "rfc2553emu.h"
  15 #include <stdlib.h>
  16 #include <arpa/inet.h>
  17 #include <iostream.h>
  18
  19 #ifndef HAVE_GETADDRINFO
  20 int getaddrinfo(const char *nodename, const char *servname,
  21                 const struct addrinfo *hints,
  22                 struct addrinfo **res)
  23 {
  24    struct addrinfo **Result;
  25    hostent *Addr;
  26    unsigned int Port;
  27    int Proto;
  28    const char *End;
  29    char **CurAddr;
  30
  31    Addr = gethostbyname(nodename);
  32    if (Addr == 0)
  33    {
  34       if (h_errno == TRY_AGAIN)
  35          return EAI_AGAIN;
  36       if (h_errno == NO_RECOVERY)
  37          return EAI_FAIL;
  38       return EAI_NONAME;
  39    }
  40
  41    // No A records
  42    if (Addr->h_addr_list[0] == 0)
  43       return EAI_NONAME;
  44
  45    // Try to convert the service as a number
  46    Port = htons(strtol(servname,(char **)&End,0));
  47    Proto = SOCK_STREAM;
  48
  49    if (hints != 0 && hints->ai_socktype != 0)
  50       Proto = hints->ai_socktype;
  51
  52    // Not a number, must be a name.
  53    if (End != servname + strlen(End))
  54    {
  55       struct servent *Srv = 0;
  56
  57       // Do a lookup in the service database
  58       if (hints == 0 || hints->ai_socktype == SOCK_STREAM)
  59          Srv = getservbyname(servname,"tcp");
  60       if (hints != 0 && hints->ai_socktype == SOCK_DGRAM)
  61          Srv = getservbyname(servname,"udp");
  62       if (Srv == 0)
  63          return EAI_NONAME;
  64
  65       // Get the right protocol
  66       Port = Srv->s_port;
  67       if (strcmp(Srv->s_proto,"tcp") == 0)
  68          Proto = SOCK_STREAM;
  69       else
  70       {
  71          if (strcmp(Srv->s_proto,"udp") == 0)
  72             Proto = SOCK_DGRAM;
  73          else
  74             return EAI_NONAME;
  75       }
  76
  77       if (hints != 0 && hints->ai_socktype != Proto &&
  78           hints->ai_socktype != 0)
  79          return EAI_SERVICE;
  80    }
  81
  82    // Start constructing the linked list
  83    *res = 0;
  84    for (CurAddr = Addr->h_addr_list; *CurAddr != 0; CurAddr++)
  85    {
  86       // New result structure
  87       *Result = (struct addrinfo *)calloc(sizeof(**Result),1);
  88       if (*Result == 0)
  89       {
  90          freeaddrinfo(*res);
  91          return EAI_MEMORY;
  92       }
  93       if (*res == 0)
  94          *res = *Result;
  95
  96       (*Result)->ai_family = AF_INET;
  97       (*Result)->ai_socktype = Proto;
  98
  99       // If we have the IPPROTO defines we can set the protocol field
 100       #ifdef IPPROTO_TCP
 101       if (Proto == SOCK_STREAM)
 102          (*Result)->ai_protocol = IPPROTO_TCP;
 103       if (Proto == SOCK_DGRAM)
 104          (*Result)->ai_protocol = IPPROTO_UDP;
 105       #endif
 106
 107       // Allocate space for the address
 108       (*Result)->ai_addrlen = sizeof(struct sockaddr_in);
 109       (*Result)->ai_addr = (struct sockaddr *)calloc(sizeof(sockaddr_in),1);
 110       if ((*Result)->ai_addr == 0)
 111       {
 112          freeaddrinfo(*res);
 113          return EAI_MEMORY;
 114       }
 115
 116       // Set the address
 117       ((struct sockaddr_in *)(*Result)->ai_addr)->sin_family = AF_INET;
 118       ((struct sockaddr_in *)(*Result)->ai_addr)->sin_port = Port;
 119       ((struct sockaddr_in *)(*Result)->ai_addr)->sin_addr = *(in_addr *)(*CurAddr);
 120
 121       Result = &(*Result)->ai_next;
 122    }
 123
 124    return 0;
 125 }
 126
 127 void freeaddrinfo(struct addrinfo *ai)
 128 {
 129    struct addrinfo *Tmp;
 130    while (ai != 0)
 131    {
 132       free(ai->ai_addr);
 133       Tmp = ai;
 134       ai = ai->ai_next;
 135       free(ai);
 136    }
 137 }
 138
 139 #endif // HAVE_GETADDRINFO