Commit 23673ca7 authored by Anthony Liguori's avatar Anthony Liguori
Browse files

qemu-char: add watch support 



This allows a front-end to request for a callback when the backend
is writable again.

Signed-off-by: default avatarAnthony Liguori <aliguori@us.ibm.com>
Signed-off-by: default avatarAmit Shah <amit.shah@redhat.com>
Message-id: 96f93c0f741064604bbb6389ce962191120af8b7.1362505276.git.amit.shah@redhat.com
Signed-off-by: default avatarAnthony Liguori <aliguori@us.ibm.com>
parent 2ea5a7af

include/char/char.h

+4 −0
Original line number Diff line number Diff line
@@ -56,6 +56,7 @@ typedef void IOEventHandler(void *opaque, int event); 
struct CharDriverState {

    void (*init)(struct CharDriverState *s);

    int (*chr_write)(struct CharDriverState *s, const uint8_t *buf, int len);

    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);
@@ -152,6 +153,9 @@ void qemu_chr_fe_close(struct CharDriverState *chr); 
void qemu_chr_fe_printf(CharDriverState *s, const char *fmt, ...)

    GCC_FMT_ATTR(2, 3);



guint qemu_chr_fe_add_watch(CharDriverState *s, GIOCondition cond,

                            GIOFunc func, void *user_data);



/**

 * @qemu_chr_fe_write:

 *

qemu-char.c

+31 −1
Original line number Diff line number Diff line
@@ -686,7 +686,11 @@ static int io_channel_send_all(GIOChannel *fd, const void *_buf, int len1) 
        status = g_io_channel_write_chars(fd, (const gchar *)buf, len,

                                          &bytes_written, NULL);

        if (status != G_IO_STATUS_NORMAL) {

            if (status != G_IO_STATUS_AGAIN) {

            if (status == G_IO_STATUS_AGAIN) {

                errno = EAGAIN;

                return -1;

            } else {

                errno = EINVAL;

                return -1;

            }

        } else if (status == G_IO_STATUS_EOF) {
@@ -753,6 +757,12 @@ static int fd_chr_read_poll(void *opaque) 
    return s->max_size;

}



static GSource *fd_chr_add_watch(CharDriverState *chr, GIOCondition cond)

{

    FDCharDriver *s = chr->opaque;

    return g_io_create_watch(s->fd_out, cond);

}



static void fd_chr_update_read_handler(CharDriverState *chr)

{

    FDCharDriver *s = chr->opaque;
@@ -796,8 +806,10 @@ static CharDriverState *qemu_chr_open_fd(int fd_in, int fd_out) 
    s = g_malloc0(sizeof(FDCharDriver));

    s->fd_in = io_channel_from_fd(fd_in);

    s->fd_out = io_channel_from_fd(fd_out);

    fcntl(fd_out, F_SETFL, O_NONBLOCK);

    s->chr = chr;

    chr->opaque = s;

    chr->chr_add_watch = fd_chr_add_watch;

    chr->chr_write = fd_chr_write;

    chr->chr_update_read_handler = fd_chr_update_read_handler;

    chr->chr_close = fd_chr_close;
@@ -3279,6 +3291,24 @@ void qemu_chr_fe_close(struct CharDriverState *chr) 
    }

}



guint qemu_chr_fe_add_watch(CharDriverState *s, GIOCondition cond,

                            GIOFunc func, void *user_data)

{

    GSource *src;

    guint tag;



    if (s->chr_add_watch == NULL) {

        return -ENOSYS;

    }



    src = s->chr_add_watch(s, cond);

    g_source_set_callback(src, (GSourceFunc)func, user_data, NULL);

    tag = g_source_attach(src, NULL);

    g_source_unref(src);



    return tag;

}



void qemu_chr_delete(CharDriverState *chr)

{

    QTAILQ_REMOVE(&chardevs, chr, next);