Add chardev API qemu_chr_fe_get_msgfds

This extends the existing qemu_chr_fe_get_msgfd by allowing to read a set
of fds. The function for receiving the fds - unix_process_msgfd is extended
to allocate the needed array size.

Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Nikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
This commit is contained in:
Nikolay Nikolaev 2014-05-27 15:04:15 +03:00 committed by Michael S. Tsirkin
parent d39aac7aac
commit c76bf6bb8f
2 changed files with 78 additions and 22 deletions

View File

@ -61,7 +61,7 @@ struct CharDriverState {
GSource *(*chr_add_watch)(struct CharDriverState *s, GIOCondition cond);
void (*chr_update_read_handler)(struct CharDriverState *s);
int (*chr_ioctl)(struct CharDriverState *s, int cmd, void *arg);
int (*get_msgfd)(struct CharDriverState *s);
int (*get_msgfds)(struct CharDriverState *s, int* fds, int num);
int (*set_msgfds)(struct CharDriverState *s, int *fds, int num);
int (*chr_add_client)(struct CharDriverState *chr, int fd);
IOEventHandler *chr_event;
@ -229,6 +229,19 @@ int qemu_chr_fe_ioctl(CharDriverState *s, int cmd, void *arg);
*/
int qemu_chr_fe_get_msgfd(CharDriverState *s);
/**
* @qemu_chr_fe_get_msgfds:
*
* For backends capable of fd passing, return the number of file received
* descriptors and fills the fds array up to num elements
*
* Returns: -1 if fd passing isn't supported or there are no pending file
* descriptors. If file descriptors are returned, subsequent calls to
* this function will return -1 until a client sends a new set of file
* descriptors.
*/
int qemu_chr_fe_get_msgfds(CharDriverState *s, int *fds, int num);
/**
* @qemu_chr_fe_set_msgfds:
*

View File

@ -204,7 +204,13 @@ void qemu_chr_be_write(CharDriverState *s, uint8_t *buf, int len)
int qemu_chr_fe_get_msgfd(CharDriverState *s)
{
return s->get_msgfd ? s->get_msgfd(s) : -1;
int fd;
return (qemu_chr_fe_get_msgfds(s, &fd, 1) >= 0) ? fd : -1;
}
int qemu_chr_fe_get_msgfds(CharDriverState *s, int *fds, int len)
{
return s->get_msgfds ? s->get_msgfds(s, fds, len) : -1;
}
int qemu_chr_fe_set_msgfds(CharDriverState *s, int *fds, int num)
@ -2337,7 +2343,8 @@ typedef struct {
int do_telnetopt;
int do_nodelay;
int is_unix;
int msgfd;
int *read_msgfds;
int read_msgfds_num;
int *write_msgfds;
int write_msgfds_num;
} TCPCharDriver;
@ -2469,12 +2476,20 @@ static void tcp_chr_process_IAC_bytes(CharDriverState *chr,
*size = j;
}
static int tcp_get_msgfd(CharDriverState *chr)
static int tcp_get_msgfds(CharDriverState *chr, int *fds, int num)
{
TCPCharDriver *s = chr->opaque;
int fd = s->msgfd;
s->msgfd = -1;
return fd;
int to_copy = (s->read_msgfds_num < num) ? s->read_msgfds_num : num;
if (to_copy) {
memcpy(fds, s->read_msgfds, to_copy * sizeof(int));
g_free(s->read_msgfds);
s->read_msgfds = 0;
s->read_msgfds_num = 0;
}
return to_copy;
}
static int tcp_set_msgfds(CharDriverState *chr, int *fds, int num)
@ -2503,26 +2518,46 @@ static void unix_process_msgfd(CharDriverState *chr, struct msghdr *msg)
struct cmsghdr *cmsg;
for (cmsg = CMSG_FIRSTHDR(msg); cmsg; cmsg = CMSG_NXTHDR(msg, cmsg)) {
int fd;
int fd_size, i;
if (cmsg->cmsg_len != CMSG_LEN(sizeof(int)) ||
if (cmsg->cmsg_len < CMSG_LEN(sizeof(int)) ||
cmsg->cmsg_level != SOL_SOCKET ||
cmsg->cmsg_type != SCM_RIGHTS)
cmsg->cmsg_type != SCM_RIGHTS) {
continue;
}
fd = *((int *)CMSG_DATA(cmsg));
if (fd < 0)
fd_size = cmsg->cmsg_len - CMSG_LEN(0);
if (!fd_size) {
continue;
}
/* O_NONBLOCK is preserved across SCM_RIGHTS so reset it */
qemu_set_block(fd);
/* close and clean read_msgfds */
for (i = 0; i < s->read_msgfds_num; i++) {
close(s->read_msgfds[i]);
}
#ifndef MSG_CMSG_CLOEXEC
qemu_set_cloexec(fd);
#endif
if (s->msgfd != -1)
close(s->msgfd);
s->msgfd = fd;
if (s->read_msgfds_num) {
g_free(s->read_msgfds);
}
s->read_msgfds_num = fd_size / sizeof(int);
s->read_msgfds = g_malloc(fd_size);
memcpy(s->read_msgfds, CMSG_DATA(cmsg), fd_size);
for (i = 0; i < s->read_msgfds_num; i++) {
int fd = s->read_msgfds[i];
if (fd < 0) {
continue;
}
/* O_NONBLOCK is preserved across SCM_RIGHTS so reset it */
qemu_set_block(fd);
#ifndef MSG_CMSG_CLOEXEC
qemu_set_cloexec(fd);
#endif
}
}
}
@ -2746,6 +2781,7 @@ static gboolean tcp_chr_accept(GIOChannel *channel, GIOCondition cond, void *opa
static void tcp_chr_close(CharDriverState *chr)
{
TCPCharDriver *s = chr->opaque;
int i;
if (s->fd >= 0) {
remove_fd_in_watch(chr);
if (s->chan) {
@ -2763,6 +2799,12 @@ static void tcp_chr_close(CharDriverState *chr)
}
closesocket(s->listen_fd);
}
if (s->read_msgfds_num) {
for (i = 0; i < s->read_msgfds_num; i++) {
close(s->read_msgfds[i]);
}
g_free(s->read_msgfds);
}
if (s->write_msgfds_num) {
g_free(s->write_msgfds);
}
@ -2794,7 +2836,8 @@ static CharDriverState *qemu_chr_open_socket_fd(int fd, bool do_nodelay,
s->connected = 0;
s->fd = -1;
s->listen_fd = -1;
s->msgfd = -1;
s->read_msgfds = 0;
s->read_msgfds_num = 0;
s->write_msgfds = 0;
s->write_msgfds_num = 0;
@ -2827,7 +2870,7 @@ static CharDriverState *qemu_chr_open_socket_fd(int fd, bool do_nodelay,
chr->chr_write = tcp_chr_write;
chr->chr_sync_read = tcp_chr_sync_read;
chr->chr_close = tcp_chr_close;
chr->get_msgfd = tcp_get_msgfd;
chr->get_msgfds = tcp_get_msgfds;
chr->set_msgfds = tcp_set_msgfds;
chr->chr_add_client = tcp_chr_add_client;
chr->chr_add_watch = tcp_chr_add_watch;