From 3def2c629b31cfc6dfe54a1a5464bb35359c3b10 Mon Sep 17 00:00:00 2001 From: Amit Shah Date: Mon, 21 Mar 2011 21:41:42 +0100 Subject: [PATCH 104/114] 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(+) diff --git a/qemu-char.c b/qemu-char.c index 86bdabf..88cbbd0 100644 --- a/qemu-char.c +++ b/qemu-char.c @@ -211,11 +211,14 @@ 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 dfa8c2d..b5e23a4 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_close)(struct CharDriverState *chr); void (*chr_accept_input)(struct CharDriverState *chr); @@ -74,6 +77,7 @@ struct CharDriverState { char *filename; int opened; int avail_connections; + bool write_blocked; /* Are we in a blocked state? */ QTAILQ_ENTRY(CharDriverState) next; }; -- 1.7.10.4