Commit c76bf6bb authored by Nikolay Nikolaev's avatar Nikolay Nikolaev Committed by Michael S. Tsirkin
Browse files

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: default avatarAntonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: default avatarNikolay Nikolaev <n.nikolaev@virtualopensystems.com>
Reviewed-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
parent d39aac7a

include/sysemu/char.h

+14 −1
Original line number Diff line number Diff line
@@ -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:

 *

qemu-char.c

+64 −21
Original line number Diff line number Diff line
@@ -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)
@@ -2503,16 +2518,38 @@ 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_size = cmsg->cmsg_len - CMSG_LEN(0);



        if (!fd_size) {

            continue;

        }



        /* close and clean read_msgfds */

        for (i = 0; i < s->read_msgfds_num; i++) {

            close(s->read_msgfds[i]);

        }



        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);



        fd = *((int *)CMSG_DATA(cmsg));

        if (fd < 0)

        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);
@@ -2520,9 +2557,7 @@ static void unix_process_msgfd(CharDriverState *chr, struct msghdr *msg) 
    #ifndef MSG_CMSG_CLOEXEC

            qemu_set_cloexec(fd);

    #endif

        if (s->msgfd != -1)

            close(s->msgfd);

        s->msgfd = fd;

        }

    }

}
@@ -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;