From patchwork Thu Nov 11 19:31:51 2010 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luiz Capitulino X-Patchwork-Id: 70872 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from lists.gnu.org (lists.gnu.org [199.232.76.165]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id C6C4FB713B for ; Fri, 12 Nov 2010 06:34:38 +1100 (EST) Received: from localhost ([127.0.0.1]:44436 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PGcup-00048t-Ow for incoming@patchwork.ozlabs.org; Thu, 11 Nov 2010 14:34:35 -0500 Received: from [140.186.70.92] (port=45854 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PGcsO-00030m-8b for qemu-devel@nongnu.org; Thu, 11 Nov 2010 14:32:05 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PGcsM-0002Kb-9u for qemu-devel@nongnu.org; Thu, 11 Nov 2010 14:32:04 -0500 Received: from mx1.redhat.com ([209.132.183.28]:31474) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PGcsL-0002KQ-Ug for qemu-devel@nongnu.org; Thu, 11 Nov 2010 14:32:02 -0500 Received: from int-mx01.intmail.prod.int.phx2.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id oABJW1Dd017532 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Thu, 11 Nov 2010 14:32:01 -0500 Received: from localhost (ovpn-113-43.phx2.redhat.com [10.3.113.43]) by int-mx01.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id oABJW0JQ021470; Thu, 11 Nov 2010 14:32:00 -0500 From: Luiz Capitulino To: qemu-devel@nongnu.org Date: Thu, 11 Nov 2010 17:31:51 -0200 Message-Id: <1289503913-27413-2-git-send-email-lcapitulino@redhat.com> In-Reply-To: <1289503913-27413-1-git-send-email-lcapitulino@redhat.com> References: <1289503913-27413-1-git-send-email-lcapitulino@redhat.com> X-Scanned-By: MIMEDefang 2.67 on 10.5.11.11 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. Cc: aliguori@us.ibm.com, armbru@redhat.com, avi@redhat.com Subject: [Qemu-devel] [PATCH 1/3] qemu-char: Introduce Memory driver X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org Errors-To: qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org This driver handles in-memory chardev operations. That's, all writes to this driver are stored in an internal buffer and it doesn't talk to the external world in any way. Right now it's very simple: it supports only writes. But it can be easily extended to support more operations. This is going to be used by the monitor's "HMP passthrough via QMP" feature, which needs to run monitor handlers without a backing device. Signed-off-by: Luiz Capitulino --- qemu-char.c | 70 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ qemu-char.h | 7 ++++++ 2 files changed, 77 insertions(+), 0 deletions(-) diff --git a/qemu-char.c b/qemu-char.c index 88997f9..36d23c6 100644 --- a/qemu-char.c +++ b/qemu-char.c @@ -2275,6 +2275,76 @@ static CharDriverState *qemu_chr_open_socket(QemuOpts *opts) return NULL; } +/***********************************************************/ +/* Memory chardev */ +typedef struct { + size_t outbuf_size; + size_t outbuf_capacity; + uint8_t *outbuf; +} MemoryDriver; + +static int mem_chr_write(CharDriverState *chr, const uint8_t *buf, int len) +{ + MemoryDriver *d = chr->opaque; + + /* TODO: the QString implementation has the same code, we should + * introduce a generic way to do this in cutils.c */ + if (d->outbuf_capacity < d->outbuf_size + len) { + /* grow outbuf */ + d->outbuf_capacity += len; + d->outbuf_capacity *= 2; + d->outbuf = qemu_realloc(d->outbuf, d->outbuf_capacity); + } + + memcpy(d->outbuf + d->outbuf_size, buf, len); + d->outbuf_size += len; + + return len; +} + +void qemu_chr_init_mem(CharDriverState *chr) +{ + MemoryDriver *d; + + d = qemu_malloc(sizeof(*d)); + d->outbuf_size = 0; + d->outbuf_capacity = 4096; + d->outbuf = qemu_mallocz(d->outbuf_capacity); + + memset(chr, 0, sizeof(*chr)); + chr->opaque = d; + chr->chr_write = mem_chr_write; +} + +/* assumes the stored data is a string */ +QString *qemu_chr_mem_to_qs(CharDriverState *chr) +{ + MemoryDriver *d = chr->opaque; + + if (d->outbuf_size == 0) { + return qstring_new(); + } + + return qstring_from_substr((char *) d->outbuf, 0, d->outbuf_size - 1); +} + +/* NOTE: this driver can not be closed with qemu_chr_close()! */ +void qemu_chr_close_mem(CharDriverState *chr) +{ + MemoryDriver *d = chr->opaque; + + qemu_free(d->outbuf); + qemu_free(chr->opaque); + chr->opaque = NULL; + chr->chr_write = NULL; +} + +size_t qemu_chr_mem_osize(const CharDriverState *chr) +{ + const MemoryDriver *d = chr->opaque; + return d->outbuf_size; +} + QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename) { char host[65], port[33], width[8], height[8]; diff --git a/qemu-char.h b/qemu-char.h index 18ad12b..e6ee6c4 100644 --- a/qemu-char.h +++ b/qemu-char.h @@ -6,6 +6,7 @@ #include "qemu-option.h" #include "qemu-config.h" #include "qobject.h" +#include "qstring.h" /* character device */ @@ -100,6 +101,12 @@ CharDriverState *qemu_chr_open_eventfd(int eventfd); extern int term_escape_char; +/* memory chardev */ +void qemu_chr_init_mem(CharDriverState *chr); +void qemu_chr_close_mem(CharDriverState *chr); +QString *qemu_chr_mem_to_qs(CharDriverState *chr); +size_t qemu_chr_mem_osize(const CharDriverState *chr); + /* async I/O support */ int qemu_set_fd_handler2(int fd,