minix/lib/ip/recvfrom.c
2005-07-27 11:57:59 +00:00

120 lines
2.4 KiB
C

#undef NDEBUG
#include <assert.h>
#include <errno.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <net/gen/in.h>
#include <net/gen/udp.h>
#include <net/gen/udp_hdr.h>
#include <net/gen/udp_io.h>
#define DEBUG 0
static ssize_t _udp_recvfrom(int socket, void *_RESTRICT buffer, size_t length,
int flags, struct sockaddr *_RESTRICT address,
socklen_t *_RESTRICT address_len, nwio_udpopt_t *udpoptp);
ssize_t recvfrom(int socket, void *_RESTRICT buffer, size_t length,
int flags, struct sockaddr *_RESTRICT address,
socklen_t *_RESTRICT address_len)
{
int r;
nwio_udpopt_t udpopt;
fprintf(stderr, "recvfrom: for fd %d\n", socket);
r= ioctl(socket, NWIOGUDPOPT, &udpopt);
if (r != -1 || (errno != ENOTTY && errno != EBADIOCTL))
{
if (r == -1)
return r;
return _udp_recvfrom(socket, buffer, length, flags,
address, address_len, &udpopt);
}
#if DEBUG
fprintf(stderr, "recvfrom: not implemented for fd %d\n", socket);
#endif
errno= ENOSYS;
assert(0);
return -1;
}
static ssize_t _udp_recvfrom(int socket, void *_RESTRICT buffer, size_t length,
int flags, struct sockaddr *_RESTRICT address,
socklen_t *_RESTRICT address_len, nwio_udpopt_t *udpoptp)
{
int r, t_errno;
size_t buflen, len;
void *buf;
struct sockaddr_in *sinp;
udp_io_hdr_t *io_hdrp;
struct sockaddr_in sin;
if (flags)
{
#if DEBUG
fprintf(stderr, "recvfrom(udp): flags not implemented\n");
#endif
errno= ENOSYS;
return -1;
}
if (udpoptp->nwuo_flags & NWUO_RWDATONLY)
{
#if DEBUG
fprintf(stderr,
"recvfrom(udp): NWUO_RWDATONLY not implemented\n");
#endif
errno= ENOSYS;
return -1;
}
buflen= sizeof(*io_hdrp) + length;
if (buflen < length)
{
/* Overflow */
errno= EMSGSIZE;
return -1;
}
buf= malloc(buflen);
if (buf == NULL)
return -1;
r= read(socket, buf, buflen);
if (r == -1)
{
t_errno= errno;
free(buf);
errno= t_errno;
return -1;
}
assert(r >= sizeof(*io_hdrp));
length= r-sizeof(*io_hdrp);
io_hdrp= buf;
memcpy(buffer, &io_hdrp[1], length);
if (address != NULL)
{
sin.sin_family= AF_INET;
sin.sin_addr.s_addr= io_hdrp->uih_src_addr;
sin.sin_port= io_hdrp->uih_src_port;
len= *address_len;
if (len > sizeof(sin))
len= sizeof(sin);
memcpy(address, &sin, len);
*address_len= sizeof(sin);
}
free(buf);
return length;
}