sys/src/ape/lib/bsd/getnameinfo.c

   1 /* posix */
   2 #include <sys/types.h>
   3 #include <unistd.h>
   4 #include <stdlib.h>
   5 #include <stdio.h>
   6 #include <fcntl.h>
   7 #include <string.h>
   8 #include <errno.h>
   9
  10 /* bsd extensions */
  11 #include <sys/uio.h>
  12 #include <sys/socket.h>
  13 #include <netinet/in.h>
  14 #include <netdb.h>
  15
  16 #include "priv.h"
  17
  18 static int
  19 netquery(char *buf, int nbuf)
  20 {
  21         int fd, i, n;
  22
  23         if((fd = open("/net/cs", O_RDWR)) < 0)
  24                 return EAI_SYSTEM;
  25         n = strlen(buf);
  26         if(write(fd, buf, n) != n){
  27                 close(fd);
  28                 return EAI_NONAME;
  29         }
  30         lseek(fd, 0, 0);
  31         for(i = 0; i < nbuf-1; i += n){
  32                 n = read(fd, buf+i, nbuf - 1 - i);
  33                 if(n <= 0)
  34                         break;
  35                 buf[i+n++] = ' ';
  36         }
  37         close(fd);
  38         buf[i] = 0;
  39         return i;
  40 }
  41
  42 int
  43 getnameinfo(struct sockaddr *sa, int salen,
  44         char *host, int hostlen,
  45         char *serv, int servlen,
  46         unsigned int flags)
  47 {
  48         char buf[8*1024], *b, *p;
  49         int err;
  50
  51         if(sa->sa_family != AF_INET && sa->sa_family != AF_INET6)
  52                 return EAI_FAMILY;
  53
  54         if(host != 0 && hostlen > 0){
  55                 if(inet_ntop(sa->sa_family, _sock_inip(sa), host, hostlen) == 0)
  56                         return EAI_SYSTEM;
  57
  58                 if((flags & NI_NUMERICHOST) == 0){
  59                         snprintf(buf, sizeof(buf), "!ip=%s", host);
  60                         if((err = netquery(buf, sizeof(buf))) < 0){
  61                                 if((flags & NI_NAMEREQD) != 0)
  62                                         return err;
  63                         } else {
  64                                 char *sys, *dom;
  65
  66                                 sys = dom = 0;
  67                                 for(b = buf;;){
  68                                         if((p = strchr(b, '=')) == 0)
  69                                                 break;
  70                                         *p++ = 0;
  71                                         if(strcmp(b, "sys") == 0)
  72                                                 sys = p;
  73                                         else if(strcmp(b, "dom") == 0)
  74                                                 dom = p;
  75                                         while(*p && *p != ' ')
  76                                                 p++;
  77                                         while(*p == ' ')
  78                                                 *p++ = 0;
  79                                         b = p;
  80                                 }
  81                                 if(sys == 0){
  82                                         if(dom == 0 && (flags & NI_NAMEREQD) != 0)
  83                                                 return EAI_NONAME;
  84                                         if(dom != 0 && (flags & NI_NOFQDN) != 0){
  85                                                 if((p = strchr(dom, '.')) != 0)
  86                                                         *p = 0;
  87                                         }
  88                                         sys = dom;
  89                                 }
  90                                 snprintf(host, hostlen, "%s", sys);
  91                         }
  92                 }
  93         }
  94
  95         if(serv != 0 && servlen > 0){
  96                 snprintf(serv, servlen, "%d", _sock_inport(sa));
  97                 if((flags & NI_NUMERICSERV) == 0){
  98                         snprintf(buf, sizeof(buf), "!port=%s", serv);
  99                         if(netquery(buf, sizeof(buf)) > 0){
 100                                 char *tcp, *udp;
 101
 102                                 tcp = udp = 0;
 103                                 for(b = buf;;){
 104                                         if((p = strchr(b, '=')) == 0)
 105                                                 break;
 106                                         *p++ = 0;
 107                                         if(strcmp(b, "tcp") == 0)
 108                                                 tcp = p;
 109                                         else if(strcmp(b, "udp") == 0)
 110                                                 udp = p;
 111                                         while(*p && *p != ' ')
 112                                                 p++;
 113                                         while(*p == ' ')
 114                                                 *p++ = 0;
 115                                         b = p;
 116                                 }
 117                                 if(udp != 0 && (flags & NI_DGRAM) != 0)
 118                                         snprintf(serv, servlen, "%s", udp);
 119                                 else if(tcp != 0)
 120                                         snprintf(serv, servlen, "%s", tcp);
 121                         }
 122                 }
 123         }
 124
 125         return 0;
 126 }