/* posix */ #include #include #include #include #include #include #include /* bsd extensions */ #include #include #include #include #include "priv.h" int h_errno; enum { Nname= 6, }; /* * for inet addresses only */ struct hostent* gethostbyname(const char *name) { int i, t, fd, m; char *p, *bp; int nn, na; unsigned long x; static struct hostent h; static char buf[1024]; static char *nptr[Nname+1]; static char *aptr[Nname+1]; static char addr[Nname][4]; h.h_name = 0; t = _sock_ipattr(name); /* connect to server */ fd = open("/net/cs", O_RDWR); if(fd < 0){ _syserrno(); h_errno = NO_RECOVERY; return 0; } /* construct the query, always expect an ip# back */ switch(t){ case Tsys: snprintf(buf, sizeof buf, "!sys=%s ip=*", name); break; case Tdom: snprintf(buf, sizeof buf, "!dom=%s ip=*", name); break; case Tip: snprintf(buf, sizeof buf, "!ip=%s", name); break; } /* query the server */ if(write(fd, buf, strlen(buf)) < 0){ _syserrno(); h_errno = TRY_AGAIN; return 0; } lseek(fd, 0, 0); for(i = 0; i < sizeof(buf)-1; i += m){ m = read(fd, buf+i, sizeof(buf) - 1 - i); if(m <= 0) break; buf[i+m++] = ' '; } close(fd); buf[i] = 0; /* parse the reply */ nn = na = 0; for(bp = buf;;){ p = strchr(bp, '='); if(p == 0) break; *p++ = 0; if(strcmp(bp, "dom") == 0){ if(h.h_name == 0) h.h_name = p; if(nn < Nname) nptr[nn++] = p; } else if(strcmp(bp, "sys") == 0){ if(nn < Nname) nptr[nn++] = p; } else if(strcmp(bp, "ip") == 0){ x = inet_addr(p); x = ntohl(x); if(na < Nname){ addr[na][0] = x>>24; addr[na][1] = x>>16; addr[na][2] = x>>8; addr[na][3] = x; aptr[na] = addr[na]; na++; } } while(*p && *p != ' ') p++; if(*p) *p++ = 0; bp = p; } if(nn+na == 0){ h_errno = HOST_NOT_FOUND; return 0; } nptr[nn] = 0; aptr[na] = 0; h.h_aliases = nptr; h.h_addr_list = aptr; h.h_length = 4; h.h_addrtype = AF_INET; if(h.h_name == 0) h.h_name = nptr[0]; if(h.h_name == 0) h.h_name = aptr[0]; return &h; }