/*
* QEMU System Emulator
*
* Copyright (c) 2003-2008 Fabrice Bellard
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "qemu/osdep.h"
#include "chardev/char.h"
#include "qapi/error.h"
#include "qapi/qapi-commands-char.h"
#include "qemu/base64.h"
#include "qemu/module.h"
#include "qemu/option.h"
#include "qom/object.h"
/* Ring buffer chardev */
struct RingBufChardev {
Chardev parent;
size_t size;
size_t prod;
size_t cons;
uint8_t *cbuf;
};
typedef struct RingBufChardev RingBufChardev;
DECLARE_INSTANCE_CHECKER(RingBufChardev, RINGBUF_CHARDEV,
TYPE_CHARDEV_RINGBUF)
static size_t ringbuf_count(const Chardev *chr)
{
const RingBufChardev *d = RINGBUF_CHARDEV(chr);
return d->prod - d->cons;
}
static int ringbuf_chr_write(Chardev *chr, const uint8_t *buf, int len)
{
RingBufChardev *d = RINGBUF_CHARDEV(chr);
int i;
if (!buf || (len < 0)) {
return -1;
}
for (i = 0; i < len; i++) {
d->cbuf[d->prod++ & (d->size - 1)] = buf[i];
if (d->prod - d->cons > d->size) {
d->cons = d->prod - d->size;
}
}
return len;
}
static int ringbuf_chr_read(Chardev *chr, uint8_t *buf, int len)
{
RingBufChardev *d = RINGBUF_CHARDEV(chr);
int i;
qemu_mutex_lock(&chr->chr_write_lock);
for (i = 0; i < len && d->cons != d->prod; i++) {
buf[i] = d->cbuf[d->cons++ & (d->size - 1)];
}
qemu_mutex_unlock(&chr->chr_write_lock);
return i;
}
static void char_ringbuf_finalize(Object *obj)
{
RingBufChardev *d = RINGBUF_CHARDEV(obj);
g_free(d->cbuf);
}
static void qemu_chr_open_ringbuf(Chardev *chr,
ChardevBackend *backend,
bool *be_opened,
Error **errp)
{
ChardevRingbuf *opts = backend->u.ringbuf.data;
RingBufChardev *d = RINGBUF_CHARDEV(chr);
d->size = opts->has_size ? opts->size : 65536;
/* The size must be power of 2 */
if (d->size & (d->size - 1)) {
error_setg(errp, "size of ringbuf chardev must be power of two");
return;
}
d->prod = 0;
d->cons = 0;
d->cbuf = g_malloc0(d->size);
}
void qmp_ringbuf_write(const char *device, const char *data,
bool has_format, enum DataFormat format,
Error **errp)
{
Chardev *chr;
const uint8_t *write_data;
int ret;
gsize write_count;
chr = qemu_chr_find(device);
if (!chr) {
error_setg(errp, "Device '%s' not found", device);
return;
}
if (!CHARDEV_IS_RINGBUF(chr)) {
error_setg(errp, "%s is not a ringbuf device", device);
return;
}
if (has_format && (format == DATA_FORMAT_BASE64)) {
write_data = qbase64_decode(data, -1,
&write_count,
errp);
if (!write_data) {
return;
}
} else {
write_data = (uint8_t *)data;
write_count = strlen(data);
}
ret = ringbuf_chr_write(chr, write_data, write_count);
if (write_data != (uint8_t *)data) {
g_free((void *)write_data);
}
if (ret < 0) {
error_setg(errp, "Failed to write to device %s", device);
return;
}
}
char *qmp_ringbuf_read(const char *device, int64_t size,
bool has_format, enum DataFormat format,
Error **errp)
{
Chardev *chr;
uint8_t *read_data;
size_t count;
char *data;
chr = qemu_chr_find(device);
if (!chr) {
error_setg(errp, "Device '%s' not found", device);
return NULL;
}
if (!CHARDEV_IS_RINGBUF(chr)) {
error_setg(errp, "%s is not a ringbuf device", device);
return NULL;
}
if (size <= 0) {
error_setg(errp, "size must be greater than zero");
return NULL;
}
count = ringbuf_count(chr);
size = size > count ? count : size;
read_data = g_malloc(size + 1);
ringbuf_chr_read(chr, read_data, size);
if (has_format && (format == DATA_FORMAT_BASE64)) {
data = g_base64_encode(read_data, size);
g_free(read_data);
} else {
/*
* FIXME should read only complete, valid UTF-8 characters up
* to @size bytes. Invalid sequences should be replaced by a
* suitable replacement character. Except when (and only
* when) ring buffer lost characters since last read, initial
* continuation characters should be dropped.
*/
read_data[size] = 0;
data = (char *)read_data;
}
return data;
}
static void qemu_chr_parse_ringbuf(QemuOpts *opts, ChardevBackend *backend,
Error **errp)
{
int val;
ChardevRingbuf *ringbuf;
backend->type = CHARDEV_BACKEND_KIND_RINGBUF;
ringbuf = backend->u.ringbuf.data = g_new0(ChardevRingbuf, 1);
qemu_chr_parse_common(opts, qapi_ChardevRingbuf_base(ringbuf));
val = qemu_opt_get_size(opts, "size", 0);
if (val != 0) {
ringbuf->has_size = true;
ringbuf->size = val;
}
}
static void char_ringbuf_class_init(ObjectClass *oc, void *data)
{
ChardevClass *cc = CHARDEV_CLASS(oc);
cc->parse = qemu_chr_parse_ringbuf;
cc->open = qemu_chr_open_ringbuf;
cc->chr_write = ringbuf_chr_write;
}
static const TypeInfo char_ringbuf_type_info = {
.name = TYPE_CHARDEV_RINGBUF,
.parent = TYPE_CHARDEV,
.class_init = char_ringbuf_class_init,
.instance_size = sizeof(RingBufChardev),
.instance_finalize = char_ringbuf_finalize,
};
/* Bug-compatibility: */
static const TypeInfo char_memory_type_info = {
.name = TYPE_CHARDEV_MEMORY,
.parent = TYPE_CHARDEV_RINGBUF,
};
static void register_types(void)
{
type_register_static(&char_ringbuf_type_info);
type_register_static(&char_memory_type_info);
}
type_init(register_types);
