qemu/include/sysemu/char.h
Marc-André Lureau fa394ed625 char: make some qemu_chr_fe skip if no driver
In most cases, front ends do not care about the side effect of
CharBackend, so we can simply skip the checks and call the qemu_chr_fe
functions even without associated CharDriver.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <20161022095318.17775-20-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-10-24 15:27:21 +02:00

498 lines
14 KiB
C

#ifndef QEMU_CHAR_H
#define QEMU_CHAR_H
#include "qemu-common.h"
#include "qemu/queue.h"
#include "qemu/option.h"
#include "qemu/config-file.h"
#include "block/aio.h"
#include "qapi/qmp/qobject.h"
#include "qapi/qmp/qstring.h"
#include "qemu/main-loop.h"
#include "qemu/bitmap.h"
/* character device */
#define CHR_EVENT_BREAK 0 /* serial break char */
#define CHR_EVENT_FOCUS 1 /* focus to this terminal (modal input needed) */
#define CHR_EVENT_OPENED 2 /* new connection established */
#define CHR_EVENT_MUX_IN 3 /* mux-focus was set to this terminal */
#define CHR_EVENT_MUX_OUT 4 /* mux-focus will move on */
#define CHR_EVENT_CLOSED 5 /* connection closed */
#define CHR_IOCTL_SERIAL_SET_PARAMS 1
typedef struct {
int speed;
int parity;
int data_bits;
int stop_bits;
} QEMUSerialSetParams;
#define CHR_IOCTL_SERIAL_SET_BREAK 2
#define CHR_IOCTL_PP_READ_DATA 3
#define CHR_IOCTL_PP_WRITE_DATA 4
#define CHR_IOCTL_PP_READ_CONTROL 5
#define CHR_IOCTL_PP_WRITE_CONTROL 6
#define CHR_IOCTL_PP_READ_STATUS 7
#define CHR_IOCTL_PP_EPP_READ_ADDR 8
#define CHR_IOCTL_PP_EPP_READ 9
#define CHR_IOCTL_PP_EPP_WRITE_ADDR 10
#define CHR_IOCTL_PP_EPP_WRITE 11
#define CHR_IOCTL_PP_DATA_DIR 12
struct ParallelIOArg {
void *buffer;
int count;
};
#define CHR_IOCTL_SERIAL_SET_TIOCM 13
#define CHR_IOCTL_SERIAL_GET_TIOCM 14
#define CHR_TIOCM_CTS 0x020
#define CHR_TIOCM_CAR 0x040
#define CHR_TIOCM_DSR 0x100
#define CHR_TIOCM_RI 0x080
#define CHR_TIOCM_DTR 0x002
#define CHR_TIOCM_RTS 0x004
typedef void IOEventHandler(void *opaque, int event);
typedef enum {
/* Whether the chardev peer is able to close and
* reopen the data channel, thus requiring support
* for qemu_chr_wait_connected() to wait for a
* valid connection */
QEMU_CHAR_FEATURE_RECONNECTABLE,
/* Whether it is possible to send/recv file descriptors
* over the data channel */
QEMU_CHAR_FEATURE_FD_PASS,
QEMU_CHAR_FEATURE_LAST,
} CharDriverFeature;
/* This is the backend as seen by frontend, the actual backend is
* CharDriverState */
typedef struct CharBackend {
CharDriverState *chr;
int tag;
} CharBackend;
struct CharDriverState {
QemuMutex chr_write_lock;
int (*chr_write)(struct CharDriverState *s, const uint8_t *buf, int len);
int (*chr_sync_read)(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,
GMainContext *context, int tag);
int (*chr_ioctl)(struct CharDriverState *s, int cmd, void *arg);
int (*get_msgfds)(struct CharDriverState *s, int* fds, int num);
int (*set_msgfds)(struct CharDriverState *s, int *fds, int num);
int (*chr_add_client)(struct CharDriverState *chr, int fd);
int (*chr_wait_connected)(struct CharDriverState *chr, Error **errp);
IOEventHandler *chr_event;
IOCanReadHandler *chr_can_read;
IOReadHandler *chr_read;
void *handler_opaque;
void (*chr_close)(struct CharDriverState *chr);
void (*chr_disconnect)(struct CharDriverState *chr);
void (*chr_accept_input)(struct CharDriverState *chr);
void (*chr_set_echo)(struct CharDriverState *chr, bool echo);
void (*chr_set_fe_open)(struct CharDriverState *chr, int fe_open);
void (*chr_fe_event)(struct CharDriverState *chr, int event);
void *opaque;
char *label;
char *filename;
int logfd;
int be_open;
int fe_open;
int explicit_fe_open;
int explicit_be_open;
int avail_connections;
int is_mux;
guint fd_in_tag;
bool replay;
DECLARE_BITMAP(features, QEMU_CHAR_FEATURE_LAST);
QTAILQ_ENTRY(CharDriverState) next;
};
/**
* qemu_chr_alloc:
* @backend: the common backend config
* @errp: pointer to a NULL-initialized error object
*
* Allocate and initialize a new CharDriverState.
*
* Returns: a newly allocated CharDriverState, or NULL on error.
*/
CharDriverState *qemu_chr_alloc(ChardevCommon *backend, Error **errp);
/**
* @qemu_chr_new_from_opts:
*
* Create a new character backend from a QemuOpts list.
*
* @opts see qemu-config.c for a list of valid options
*
* Returns: a new character backend
*/
CharDriverState *qemu_chr_new_from_opts(QemuOpts *opts,
Error **errp);
/**
* @qemu_chr_parse_common:
*
* Parse the common options available to all character backends.
*
* @opts the options that still need parsing
* @backend a new backend
*/
void qemu_chr_parse_common(QemuOpts *opts, ChardevCommon *backend);
/**
* @qemu_chr_new:
*
* Create a new character backend from a URI.
*
* @label the name of the backend
* @filename the URI
*
* Returns: a new character backend
*/
CharDriverState *qemu_chr_new(const char *label, const char *filename);
/**
* @qemu_chr_fe_disconnect:
*
* Close a fd accpeted by character backend.
* Without associated CharDriver, do nothing.
*/
void qemu_chr_fe_disconnect(CharBackend *be);
/**
* @qemu_chr_cleanup:
*
* Delete all chardevs (when leaving qemu)
*/
void qemu_chr_cleanup(void);
/**
* @qemu_chr_fe_wait_connected:
*
* Wait for characted backend to be connected, return < 0 on error or
* if no assicated CharDriver.
*/
int qemu_chr_fe_wait_connected(CharBackend *be, Error **errp);
/**
* @qemu_chr_new_noreplay:
*
* Create a new character backend from a URI.
* Character device communications are not written
* into the replay log.
*
* @label the name of the backend
* @filename the URI
*
* Returns: a new character backend
*/
CharDriverState *qemu_chr_new_noreplay(const char *label, const char *filename);
/**
* @qemu_chr_delete:
*
* Destroy a character backend and remove it from the list of
* identified character backends.
*/
void qemu_chr_delete(CharDriverState *chr);
/**
* @qemu_chr_free:
*
* Destroy a character backend.
*/
void qemu_chr_free(CharDriverState *chr);
/**
* @qemu_chr_fe_set_echo:
*
* Ask the backend to override its normal echo setting. This only really
* applies to the stdio backend and is used by the QMP server such that you
* can see what you type if you try to type QMP commands.
* Without associated CharDriver, do nothing.
*
* @echo true to enable echo, false to disable echo
*/
void qemu_chr_fe_set_echo(CharBackend *be, bool echo);
/**
* @qemu_chr_fe_set_open:
*
* Set character frontend open status. This is an indication that the
* front end is ready (or not) to begin doing I/O.
* Without associated CharDriver, do nothing.
*/
void qemu_chr_fe_set_open(CharBackend *be, int fe_open);
/**
* @qemu_chr_fe_event:
*
* Send an event from the front end to the back end. It does nothing
* without associated CharDriver.
*
* @event the event to send
*/
void qemu_chr_fe_event(CharBackend *be, int event);
/**
* @qemu_chr_fe_printf:
*
* Write to a character backend using a printf style interface. This
* function is thread-safe. It does nothing without associated
* CharDriver.
*
* @fmt see #printf
*/
void qemu_chr_fe_printf(CharBackend *be, const char *fmt, ...)
GCC_FMT_ATTR(2, 3);
/**
* @qemu_chr_fe_add_watch:
*
* If the backend is connected, create and add a #GSource that fires
* when the given condition (typically G_IO_OUT|G_IO_HUP or G_IO_HUP)
* is active; return the #GSource's tag. If it is disconnected,
* or without associated CharDriver, return 0.
*
* @cond the condition to poll for
* @func the function to call when the condition happens
* @user_data the opaque pointer to pass to @func
*/
guint qemu_chr_fe_add_watch(CharBackend *be, GIOCondition cond,
GIOFunc func, void *user_data);
/**
* @qemu_chr_fe_write:
*
* Write data to a character backend from the front end. This function
* will send data from the front end to the back end. This function
* is thread-safe.
*
* @buf the data
* @len the number of bytes to send
*
* Returns: the number of bytes consumed (0 if no assicated CharDriver)
*/
int qemu_chr_fe_write(CharBackend *be, const uint8_t *buf, int len);
/**
* @qemu_chr_fe_write_all:
*
* Write data to a character backend from the front end. This function will
* send data from the front end to the back end. Unlike @qemu_chr_fe_write,
* this function will block if the back end cannot consume all of the data
* attempted to be written. This function is thread-safe.
*
* @buf the data
* @len the number of bytes to send
*
* Returns: the number of bytes consumed (0 if no assicated CharDriver)
*/
int qemu_chr_fe_write_all(CharBackend *be, const uint8_t *buf, int len);
/**
* @qemu_chr_fe_read_all:
*
* Read data to a buffer from the back end.
*
* @buf the data buffer
* @len the number of bytes to read
*
* Returns: the number of bytes read (0 if no assicated CharDriver)
*/
int qemu_chr_fe_read_all(CharBackend *be, uint8_t *buf, int len);
/**
* @qemu_chr_fe_ioctl:
*
* Issue a device specific ioctl to a backend. This function is thread-safe.
*
* @cmd see CHR_IOCTL_*
* @arg the data associated with @cmd
*
* Returns: if @cmd is not supported by the backend or there is no
* associated CharDriver, -ENOTSUP, otherwise the return
* value depends on the semantics of @cmd
*/
int qemu_chr_fe_ioctl(CharBackend *be, int cmd, void *arg);
/**
* @qemu_chr_fe_get_msgfd:
*
* For backends capable of fd passing, return the latest file descriptor passed
* by a client.
*
* Returns: -1 if fd passing isn't supported or there is no pending file
* descriptor. If a file descriptor is returned, subsequent calls to
* this function will return -1 until a client sends a new file
* descriptor.
*/
int qemu_chr_fe_get_msgfd(CharBackend *be);
/**
* @qemu_chr_fe_get_msgfds:
*
* For backends capable of fd passing, return the number of file received
* descriptors and fills the fds array up to num elements
*
* Returns: -1 if fd passing isn't supported or there are no pending file
* descriptors. If file descriptors are returned, subsequent calls to
* this function will return -1 until a client sends a new set of file
* descriptors.
*/
int qemu_chr_fe_get_msgfds(CharBackend *be, int *fds, int num);
/**
* @qemu_chr_fe_set_msgfds:
*
* For backends capable of fd passing, set an array of fds to be passed with
* the next send operation.
* A subsequent call to this function before calling a write function will
* result in overwriting the fd array with the new value without being send.
* Upon writing the message the fd array is freed.
*
* Returns: -1 if fd passing isn't supported or no associated CharDriver.
*/
int qemu_chr_fe_set_msgfds(CharBackend *be, int *fds, int num);
/**
* @qemu_chr_be_can_write:
*
* Determine how much data the front end can currently accept. This function
* returns the number of bytes the front end can accept. If it returns 0, the
* front end cannot receive data at the moment. The function must be polled
* to determine when data can be received.
*
* Returns: the number of bytes the front end can receive via @qemu_chr_be_write
*/
int qemu_chr_be_can_write(CharDriverState *s);
/**
* @qemu_chr_be_write:
*
* Write data from the back end to the front end. Before issuing this call,
* the caller should call @qemu_chr_be_can_write to determine how much data
* the front end can currently accept.
*
* @buf a buffer to receive data from the front end
* @len the number of bytes to receive from the front end
*/
void qemu_chr_be_write(CharDriverState *s, uint8_t *buf, int len);
/**
* @qemu_chr_be_write_impl:
*
* Implementation of back end writing. Used by replay module.
*
* @buf a buffer to receive data from the front end
* @len the number of bytes to receive from the front end
*/
void qemu_chr_be_write_impl(CharDriverState *s, uint8_t *buf, int len);
/**
* @qemu_chr_be_event:
*
* Send an event from the back end to the front end.
*
* @event the event to send
*/
void qemu_chr_be_event(CharDriverState *s, int event);
/**
* @qemu_chr_fe_init:
*
* Initializes a front end for the given CharBackend and
* CharDriver. Call qemu_chr_fe_deinit() to remove the association and
* release the driver.
*
* Returns: false on error.
*/
bool qemu_chr_fe_init(CharBackend *b, CharDriverState *s, Error **errp);
/**
* @qemu_chr_fe_get_driver:
*
* Returns the driver associated with a CharBackend or NULL if no
* associated CharDriver.
*/
CharDriverState *qemu_chr_fe_get_driver(CharBackend *be);
/**
* @qemu_chr_fe_deinit:
*
* Dissociate the CharBackend from the CharDriver.
*
* Safe to call without associated CharDriver.
*/
void qemu_chr_fe_deinit(CharBackend *b);
/**
* @qemu_chr_fe_set_handlers:
* @b: a CharBackend
* @fd_can_read: callback to get the amount of data the frontend may
* receive
* @fd_read: callback to receive data from char
* @fd_event: event callback
* @opaque: an opaque pointer for the callbacks
* @context: a main loop context or NULL for the default
*
* Set the front end char handlers. The front end takes the focus if
* any of the handler is non-NULL.
*
* Without associated CharDriver, nothing is changed.
*/
void qemu_chr_fe_set_handlers(CharBackend *b,
IOCanReadHandler *fd_can_read,
IOReadHandler *fd_read,
IOEventHandler *fd_event,
void *opaque,
GMainContext *context);
/**
* @qemu_chr_fe_take_focus:
*
* Take the focus (if the front end is muxed).
*
* Without associated CharDriver, nothing is changed.
*/
void qemu_chr_fe_take_focus(CharBackend *b);
void qemu_chr_be_generic_open(CharDriverState *s);
void qemu_chr_fe_accept_input(CharBackend *be);
int qemu_chr_add_client(CharDriverState *s, int fd);
CharDriverState *qemu_chr_find(const char *name);
bool chr_is_ringbuf(const CharDriverState *chr);
bool qemu_chr_has_feature(CharDriverState *chr,
CharDriverFeature feature);
void qemu_chr_set_feature(CharDriverState *chr,
CharDriverFeature feature);
QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename);
void register_char_driver(const char *name, ChardevBackendKind kind,
void (*parse)(QemuOpts *opts, ChardevBackend *backend, Error **errp),
CharDriverState *(*create)(const char *id, ChardevBackend *backend,
ChardevReturn *ret, Error **errp));
extern int term_escape_char;
/* console.c */
typedef CharDriverState *(VcHandler)(ChardevVC *vc, Error **errp);
void register_vc_handler(VcHandler *handler);
#endif