>From 3ad2ca8e46ba078e69254ca5886de89b30f823bb Mon Sep 17 00:00:00 2001 From: Amit Shah Date: Mon, 21 Mar 2011 21:41:42 +0100 Subject: [PATCH 04/28] char: Add framework for a 'write unblocked' callback The char layer can let users know that the driver will block on further input. For users interested in not blocking, they can assign a function pointer that will be called back when the driver becomes writable. This patch just adds the function pointers to the CharDriverState structure, future patches will enable the nonblocking and callback functionality. Signed-off-by: Amit Shah --- qemu-char.c | 3 +++ qemu-char.h | 4 ++++ 2 files changed, 7 insertions(+), 0 deletions(-) diff --git a/qemu-char.c b/qemu-char.c index 52bcc0e..bc07b20 100644 --- a/qemu-char.c +++ b/qemu-char.c @@ -214,11 +214,14 @@ void qemu_chr_add_handlers(CharDriverState *s, } s->chr_can_read = handlers->fd_can_read; s->chr_read = handlers->fd_read; + s->chr_write_unblocked = handlers->fd_write_unblocked; s->chr_event = handlers->fd_event; s->handler_opaque = opaque; if (s->chr_update_read_handler) s->chr_update_read_handler(s); + s->write_blocked = false; + /* We're connecting to an already opened device, so let's make sure we also get the open event */ if (s->opened) { diff --git a/qemu-char.h b/qemu-char.h index 9fe1b82..68e7b5b 100644 --- a/qemu-char.h +++ b/qemu-char.h @@ -62,6 +62,9 @@ struct CharDriverState { IOEventHandler *chr_event; IOCanReadHandler *chr_can_read; IOReadHandler *chr_read; + IOHandler *chr_write_unblocked; + void (*chr_enable_write_fd_handler)(struct CharDriverState *chr); + void (*chr_disable_write_fd_handler)(struct CharDriverState *chr); void *handler_opaque; void (*chr_send_event)(struct CharDriverState *chr, int event); void (*chr_close)(struct CharDriverState *chr); @@ -75,6 +78,7 @@ struct CharDriverState { char *filename; int opened; int avail_connections; + bool write_blocked; /* Are we in a blocked state? */ QTAILQ_ENTRY(CharDriverState) next; }; -- 1.7.5.1