| #ifndef QEMU_CHAR_FE_H |
| #define QEMU_CHAR_FE_H |
| |
| #include "chardev/char.h" |
| #include "qemu/main-loop.h" |
| |
| typedef void IOEventHandler(void *opaque, int event); |
| typedef int BackendChangeHandler(void *opaque); |
| |
| /* This is the backend as seen by frontend, the actual backend is |
| * Chardev */ |
| struct CharBackend { |
| Chardev *chr; |
| IOEventHandler *chr_event; |
| IOCanReadHandler *chr_can_read; |
| IOReadHandler *chr_read; |
| BackendChangeHandler *chr_be_change; |
| void *opaque; |
| int tag; |
| int fe_open; |
| }; |
| |
| /** |
| * qemu_chr_fe_init: |
| * |
| * Initializes a front end for the given CharBackend and |
| * Chardev. Call qemu_chr_fe_deinit() to remove the association and |
| * release the driver. |
| * |
| * Returns: false on error. |
| */ |
| bool qemu_chr_fe_init(CharBackend *b, Chardev *s, Error **errp); |
| |
| /** |
| * qemu_chr_fe_deinit: |
| * @b: a CharBackend |
| * @del: if true, delete the chardev backend |
| * |
| * Dissociate the CharBackend from the Chardev. |
| * |
| * Safe to call without associated Chardev. |
| */ |
| void qemu_chr_fe_deinit(CharBackend *b, bool del); |
| |
| /** |
| * qemu_chr_fe_get_driver: |
| * |
| * Returns: the driver associated with a CharBackend or NULL if no |
| * associated Chardev. |
| * Note: avoid this function as the driver should never be accessed directly, |
| * especially by the frontends that support chardevice hotswap. |
| * Consider qemu_chr_fe_backend_connected() to check for driver existence |
| */ |
| Chardev *qemu_chr_fe_get_driver(CharBackend *be); |
| |
| /** |
| * qemu_chr_fe_backend_connected: |
| * |
| * Returns: true if there is a chardevice associated with @be. |
| */ |
| bool qemu_chr_fe_backend_connected(CharBackend *be); |
| |
| /** |
| * qemu_chr_fe_backend_open: |
| * |
| * Returns: true if chardevice associated with @be is open. |
| */ |
| bool qemu_chr_fe_backend_open(CharBackend *be); |
| |
| /** |
| * qemu_chr_fe_set_handlers_full: |
| * @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 |
| * @be_change: backend change callback; passing NULL means hot backend change |
| * is not supported and will not be attempted |
| * @opaque: an opaque pointer for the callbacks |
| * @context: a main loop context or NULL for the default |
| * @set_open: whether to call qemu_chr_fe_set_open() implicitely when |
| * any of the handler is non-NULL |
| * @sync_state: whether to issue event callback with updated state |
| * |
| * Set the front end char handlers. The front end takes the focus if |
| * any of the handler is non-NULL. |
| * |
| * Without associated Chardev, nothing is changed. |
| */ |
| void qemu_chr_fe_set_handlers_full(CharBackend *b, |
| IOCanReadHandler *fd_can_read, |
| IOReadHandler *fd_read, |
| IOEventHandler *fd_event, |
| BackendChangeHandler *be_change, |
| void *opaque, |
| GMainContext *context, |
| bool set_open, |
| bool sync_state); |
| |
| /** |
| * qemu_chr_fe_set_handlers: |
| * |
| * Version of qemu_chr_fe_set_handlers_full() with sync_state = true. |
| */ |
| void qemu_chr_fe_set_handlers(CharBackend *b, |
| IOCanReadHandler *fd_can_read, |
| IOReadHandler *fd_read, |
| IOEventHandler *fd_event, |
| BackendChangeHandler *be_change, |
| void *opaque, |
| GMainContext *context, |
| bool set_open); |
| |
| /** |
| * qemu_chr_fe_take_focus: |
| * |
| * Take the focus (if the front end is muxed). |
| * |
| * Without associated Chardev, nothing is changed. |
| */ |
| void qemu_chr_fe_take_focus(CharBackend *b); |
| |
| /** |
| * qemu_chr_fe_accept_input: |
| * |
| * Notify that the frontend is ready to receive data |
| */ |
| void qemu_chr_fe_accept_input(CharBackend *be); |
| |
| /** |
| * qemu_chr_fe_disconnect: |
| * |
| * Close a fd accepted by character backend. |
| * Without associated Chardev, do nothing. |
| */ |
| void qemu_chr_fe_disconnect(CharBackend *be); |
| |
| /** |
| * qemu_chr_fe_wait_connected: |
| * |
| * Wait for characted backend to be connected, return < 0 on error or |
| * if no associated Chardev. |
| */ |
| int qemu_chr_fe_wait_connected(CharBackend *be, Error **errp); |
| |
| /** |
| * qemu_chr_fe_set_echo: |
| * @echo: true to enable echo, false to disable 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 Chardev, do nothing. |
| */ |
| 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 Chardev, do nothing. |
| */ |
| void qemu_chr_fe_set_open(CharBackend *be, int fe_open); |
| |
| /** |
| * qemu_chr_fe_printf: |
| * @fmt: see #printf |
| * |
| * Write to a character backend using a printf style interface. This |
| * function is thread-safe. It does nothing without associated |
| * Chardev. |
| */ |
| void qemu_chr_fe_printf(CharBackend *be, const char *fmt, ...) |
| GCC_FMT_ATTR(2, 3); |
| |
| /** |
| * qemu_chr_fe_add_watch: |
| * @cond: the condition to poll for |
| * @func: the function to call when the condition happens |
| * @user_data: the opaque pointer to pass to @func |
| * |
| * 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 Chardev, return 0. |
| * |
| * Note that you are responsible to update the front-end sources if |
| * you are switching the main context with qemu_chr_fe_set_handlers(). |
| * |
| * Returns: the source tag |
| */ |
| guint qemu_chr_fe_add_watch(CharBackend *be, GIOCondition cond, |
| GIOFunc func, void *user_data); |
| |
| /** |
| * qemu_chr_fe_write: |
| * @buf: the data |
| * @len: the number of bytes to send |
| * |
| * 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. |
| * |
| * Returns: the number of bytes consumed (0 if no associated Chardev) |
| */ |
| int qemu_chr_fe_write(CharBackend *be, const uint8_t *buf, int len); |
| |
| /** |
| * qemu_chr_fe_write_all: |
| * @buf: the data |
| * @len: the number of bytes to send |
| * |
| * 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. |
| * |
| * Returns: the number of bytes consumed (0 if no associated Chardev) |
| */ |
| int qemu_chr_fe_write_all(CharBackend *be, const uint8_t *buf, int len); |
| |
| /** |
| * qemu_chr_fe_read_all: |
| * @buf: the data buffer |
| * @len: the number of bytes to read |
| * |
| * Read data to a buffer from the back end. |
| * |
| * Returns: the number of bytes read (0 if no associated Chardev) |
| */ |
| int qemu_chr_fe_read_all(CharBackend *be, uint8_t *buf, int len); |
| |
| /** |
| * qemu_chr_fe_ioctl: |
| * @cmd: see CHR_IOCTL_* |
| * @arg: the data associated with @cmd |
| * |
| * Issue a device specific ioctl to a backend. This function is thread-safe. |
| * |
| * Returns: if @cmd is not supported by the backend or there is no |
| * associated Chardev, -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 Chardev. |
| */ |
| int qemu_chr_fe_set_msgfds(CharBackend *be, int *fds, int num); |
| |
| #endif /* QEMU_CHAR_FE_H */ |