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#include <sys/cdefs.h>
#include "namespace.h"
#include <lib.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/ioctl.h>
#include <sys/ioc_net.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <sys/un.h>
#define DEBUG 0
static ssize_t _uds_recvmsg_conn(int sock, struct msghdr *msg, int flags);
static ssize_t _uds_recvmsg_dgram(int sock, struct msghdr *msg, int flags);
/*
* Receive a message from a socket using a message structure.
*/
static ssize_t
__recvmsg(int fd, struct msghdr * msg, int flags)
{
struct iovec iov;
struct msghdr msg2, *msgp;
char *ptr;
message m;
ssize_t r;
/*
* Currently, MINIX3 does not support vector I/O operations. Like in
* the readv and writev implementations, we coalesce the data vector
* into a single buffer used for I/O. For future ABI compatibility, we
* then supply this buffer as a single vector element. This involves
* supplying a modified copy of the message header, as well as extra
* pre-checks. Once true vector I/O support has been added, the checks
* and vector I/O coalescing can be removed from here, leaving just the
* system call. Nothing will change at the system call ABI level.
*/
if (msg == NULL || (msg->msg_iovlen > 1 && msg->msg_iov == NULL)) {
errno = EFAULT;
return -1;
}
if (msg->msg_iovlen < 0 || msg->msg_iovlen > IOV_MAX) {
errno = EMSGSIZE; /* different from readv/writev */
return -1;
}
if (msg->msg_iovlen > 1) {
if ((r = _vectorio_setup(msg->msg_iov, msg->msg_iovlen, &ptr,
_VECTORIO_READ)) < 0)
return -1;
iov.iov_base = ptr;
iov.iov_len = r;
memcpy(&msg2, msg, sizeof(msg2));
msg2.msg_iov = &iov;
msg2.msg_iovlen = 1;
msgp = &msg2;
} else
msgp = msg;
/* Issue the actual system call. */
memset(&m, 0, sizeof(m));
m.m_lc_vfs_sockmsg.fd = fd;
m.m_lc_vfs_sockmsg.msgbuf = (vir_bytes)msgp;
m.m_lc_vfs_sockmsg.flags = flags;
r = _syscall(VFS_PROC_NR, VFS_RECVMSG, &m);
/* If we coalesced the vector, clean up and copy back the results. */
if (msgp != msg) {
_vectorio_cleanup(msg->msg_iov, msg->msg_iovlen, ptr, r,
_VECTORIO_READ);
if (r >= 0)
memcpy(msg, &msg2, sizeof(msg2));
}
return r;
}
ssize_t recvmsg(int sock, struct msghdr *msg, int flags)
{
int r;
int uds_sotype;
r = __recvmsg(sock, msg, flags);
if (r != -1 || (errno != ENOTSOCK && errno != ENOSYS))
return r;
if (msg == NULL) {
errno= EFAULT;
return -1;
}
r= ioctl(sock, NWIOGUDSSOTYPE, &uds_sotype);
if (r != -1 || errno != ENOTTY) {
if (r == -1) {
return r;
}
if (uds_sotype == SOCK_DGRAM) {
return _uds_recvmsg_dgram(sock, msg, flags);
} else {
return _uds_recvmsg_conn(sock, msg, flags);
}
}
errno = ENOTSOCK;
return -1;
}
static ssize_t _uds_recvmsg_conn(int sock, struct msghdr *msg, int flags)
{
int r, rc;
if (flags != 0) {
#if DEBUG
fprintf(stderr, "recvmsg(uds): flags not implemented\n");
#endif
errno= ENOSYS;
return -1;
}
r= readv(sock, msg->msg_iov, msg->msg_iovlen);
if (r >= 0 && msg->msg_name && msg->msg_namelen > 0) {
getpeername(sock, msg->msg_name, &msg->msg_namelen);
}
/* get control data */
if (r >= 0 && msg->msg_control && msg->msg_controllen > 0) {
struct msg_control msg_ctrl;
memset(&msg_ctrl, '\0', sizeof(struct msg_control));
msg_ctrl.msg_controllen = msg->msg_controllen;
rc = ioctl(sock, NWIOGUDSCTRL, &msg_ctrl);
if (rc == -1) {
return rc;
}
if (msg_ctrl.msg_controllen <= msg->msg_controllen) {
memcpy(msg->msg_control, msg_ctrl.msg_control,
msg_ctrl.msg_controllen);
msg->msg_controllen = msg_ctrl.msg_controllen;
}
}
msg->msg_flags = 0;
return r;
}
static ssize_t _uds_recvmsg_dgram(int sock, struct msghdr *msg, int flags)
{
int r, rc;
if (flags != 0) {
#if DEBUG
fprintf(stderr, "recvmsg(uds): flags not implemented\n");
#endif
errno= ENOSYS;
return -1;
}
r= readv(sock, msg->msg_iov, msg->msg_iovlen);
if (r >= 0 && msg->msg_name &&
msg->msg_namelen >= sizeof(struct sockaddr_un))
{
rc= ioctl(sock, NWIOGUDSFADDR, msg->msg_name);
if (rc == -1) {
return rc;
}
msg->msg_namelen= sizeof(struct sockaddr_un);
}
/* get control data */
if (r >= 0 && msg->msg_control && msg->msg_controllen > 0) {
struct msg_control msg_ctrl;
memset(&msg_ctrl, '\0', sizeof(struct msg_control));
msg_ctrl.msg_controllen = msg->msg_controllen;
rc = ioctl(sock, NWIOGUDSCTRL, &msg_ctrl);
if (rc == -1) {
return rc;
}
if (msg_ctrl.msg_controllen <= msg->msg_controllen) {
memcpy(msg->msg_control, msg_ctrl.msg_control,
msg_ctrl.msg_controllen);
msg->msg_controllen = msg_ctrl.msg_controllen;
}
}
msg->msg_flags = 0;
return r;
}
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