void dns_transmit_free (struct dns_transmit *d) { queryfree (d); socketfree (d); packetfree (d); }
int dns_transmit_get(struct dns_transmit *d,const iopause_fd *x,const struct taia *when) { char udpbuf[513]; unsigned char ch; int r; int fd; errno = error_io; fd = d->s1 - 1; if (!x->revents) { if (taia_less(when,&d->deadline)) return 0; errno = error_timeout; if (d->tcpstate == 0) return nextudp(d); return nexttcp(d); } if (d->tcpstate == 0) { /* have attempted to send UDP query to each server udploop times have sent query to curserver on UDP socket s */ r = recv(fd,udpbuf,sizeof udpbuf,0); if (r <= 0) { if (errno == error_connrefused) if (d->udploop == 2) return 0; return nextudp(d); } if (r + 1 > sizeof udpbuf) return 0; if (irrelevant(d,udpbuf,r)) return 0; if (serverwantstcp(udpbuf,r)) return firsttcp(d); if (serverfailed(udpbuf,r)) { if (d->udploop == 2) return 0; return nextudp(d); } socketfree(d); d->packetlen = r; d->packet = alloc(d->packetlen); if (!d->packet) { dns_transmit_free(d); return -1; } byte_copy(d->packet,d->packetlen,udpbuf); queryfree(d); return 1; } if (d->tcpstate == 1) { /* have sent connection attempt to curserver on TCP socket s pos not defined */ if (!socket_connected(fd)) return nexttcp(d); d->pos = 0; d->tcpstate = 2; return 0; } if (d->tcpstate == 2) { /* have connection to curserver on TCP socket s have sent pos bytes of query */ r = write(fd,d->query + d->pos,d->querylen - d->pos); if (r <= 0) return nexttcp(d); d->pos += r; if (d->pos == d->querylen) { struct taia now; taia_now(&now); taia_uint(&d->deadline,10); taia_add(&d->deadline,&d->deadline,&now); d->tcpstate = 3; } return 0; } if (d->tcpstate == 3) { /* have sent entire query to curserver on TCP socket s pos not defined */ r = read(fd,&ch,1); if (r <= 0) return nexttcp(d); d->packetlen = ch; d->tcpstate = 4; return 0; } if (d->tcpstate == 4) { /* have sent entire query to curserver on TCP socket s pos not defined have received one byte of packet length into packetlen */ r = read(fd,&ch,1); if (r <= 0) return nexttcp(d); d->packetlen <<= 8; d->packetlen += ch; d->tcpstate = 5; d->pos = 0; d->packet = alloc(d->packetlen); if (!d->packet) { dns_transmit_free(d); return -1; } return 0; } if (d->tcpstate == 5) { /* have sent entire query to curserver on TCP socket s have received entire packet length into packetlen packet is allocated have received pos bytes of packet */ r = read(fd,d->packet + d->pos,d->packetlen - d->pos); if (r <= 0) return nexttcp(d); d->pos += r; if (d->pos < d->packetlen) return 0; socketfree(d); if (irrelevant(d,d->packet,d->packetlen)) return nexttcp(d); if (serverwantstcp(d->packet,d->packetlen)) return nexttcp(d); if (serverfailed(d->packet,d->packetlen)) return nexttcp(d); queryfree(d); return 1; } return 0; }