include/sysemu/char.h

   1 #ifndef QEMU_CHAR_H
   2 #define QEMU_CHAR_H
   3
   4 #include "qemu-common.h"
   5 #include "qemu/queue.h"
   6 #include "qemu/option.h"
   7 #include "qemu/config-file.h"
   8 #include "block/aio.h"
   9 #include "qapi/qmp/qobject.h"
  10 #include "qapi/qmp/qstring.h"
  11 #include "qemu/main-loop.h"
  12 #include "qemu/bitmap.h"
  13
  14 /* character device */
  15
  16 typedef enum {
  17     CHR_EVENT_BREAK, /* serial break char */
  18     CHR_EVENT_OPENED, /* new connection established */
  19     CHR_EVENT_MUX_IN, /* mux-focus was set to this terminal */
  20     CHR_EVENT_MUX_OUT, /* mux-focus will move on */
  21     CHR_EVENT_CLOSED /* connection closed */
  22 } QEMUChrEvent;
  23
  24
  25 #define CHR_IOCTL_SERIAL_SET_PARAMS   1
  26 typedef struct {
  27     int speed;
  28     int parity;
  29     int data_bits;
  30     int stop_bits;
  31 } QEMUSerialSetParams;
  32
  33 #define CHR_IOCTL_SERIAL_SET_BREAK    2
  34
  35 #define CHR_IOCTL_PP_READ_DATA        3
  36 #define CHR_IOCTL_PP_WRITE_DATA       4
  37 #define CHR_IOCTL_PP_READ_CONTROL     5
  38 #define CHR_IOCTL_PP_WRITE_CONTROL    6
  39 #define CHR_IOCTL_PP_READ_STATUS      7
  40 #define CHR_IOCTL_PP_EPP_READ_ADDR    8
  41 #define CHR_IOCTL_PP_EPP_READ         9
  42 #define CHR_IOCTL_PP_EPP_WRITE_ADDR  10
  43 #define CHR_IOCTL_PP_EPP_WRITE       11
  44 #define CHR_IOCTL_PP_DATA_DIR        12
  45
  46 struct ParallelIOArg {
  47     void *buffer;
  48     int count;
  49 };
  50
  51 #define CHR_IOCTL_SERIAL_SET_TIOCM   13
  52 #define CHR_IOCTL_SERIAL_GET_TIOCM   14
  53
  54 #define CHR_TIOCM_CTS   0x020
  55 #define CHR_TIOCM_CAR   0x040
  56 #define CHR_TIOCM_DSR   0x100
  57 #define CHR_TIOCM_RI    0x080
  58 #define CHR_TIOCM_DTR   0x002
  59 #define CHR_TIOCM_RTS   0x004
  60
  61 typedef void IOEventHandler(void *opaque, int event);
  62
  63 typedef enum {
  64     /* Whether the chardev peer is able to close and
  65      * reopen the data channel, thus requiring support
  66      * for qemu_chr_wait_connected() to wait for a
  67      * valid connection */
  68     QEMU_CHAR_FEATURE_RECONNECTABLE,
  69     /* Whether it is possible to send/recv file descriptors
  70      * over the data channel */
  71     QEMU_CHAR_FEATURE_FD_PASS,
  72
  73     QEMU_CHAR_FEATURE_LAST,
  74 } CharDriverFeature;
  75
  76 /* This is the backend as seen by frontend, the actual backend is
  77  * CharDriverState */
  78 typedef struct CharBackend {
  79     CharDriverState *chr;
  80     IOEventHandler *chr_event;
  81     IOCanReadHandler *chr_can_read;
  82     IOReadHandler *chr_read;
  83     void *opaque;
  84     int tag;
  85     int fe_open;
  86 } CharBackend;
  87
  88 struct CharDriverState {
  89     QemuMutex chr_write_lock;
  90     int (*chr_write)(struct CharDriverState *s, const uint8_t *buf, int len);
  91     int (*chr_sync_read)(struct CharDriverState *s,
  92                          const uint8_t *buf, int len);
  93     GSource *(*chr_add_watch)(struct CharDriverState *s, GIOCondition cond);
  94     void (*chr_update_read_handler)(struct CharDriverState *s,
  95                                     GMainContext *context);
  96     int (*chr_ioctl)(struct CharDriverState *s, int cmd, void *arg);
  97     int (*get_msgfds)(struct CharDriverState *s, int* fds, int num);
  98     int (*set_msgfds)(struct CharDriverState *s, int *fds, int num);
  99     int (*chr_add_client)(struct CharDriverState *chr, int fd);
 100     int (*chr_wait_connected)(struct CharDriverState *chr, Error **errp);
 101     void (*chr_free)(struct CharDriverState *chr);
 102     void (*chr_disconnect)(struct CharDriverState *chr);
 103     void (*chr_accept_input)(struct CharDriverState *chr);
 104     void (*chr_set_echo)(struct CharDriverState *chr, bool echo);
 105     void (*chr_set_fe_open)(struct CharDriverState *chr, int fe_open);
 106     CharBackend *be;
 107     void *opaque;
 108     char *label;
 109     char *filename;
 110     int logfd;
 111     int be_open;
 112     int is_mux;
 113     guint fd_in_tag;
 114     bool replay;
 115     DECLARE_BITMAP(features, QEMU_CHAR_FEATURE_LAST);
 116     QTAILQ_ENTRY(CharDriverState) next;
 117 };
 118
 119 /**
 120  * qemu_chr_alloc:
 121  * @backend: the common backend config
 122  * @errp: pointer to a NULL-initialized error object
 123  *
 124  * Allocate and initialize a new CharDriverState.
 125  *
 126  * Returns: a newly allocated CharDriverState, or NULL on error.
 127  */
 128 CharDriverState *qemu_chr_alloc(ChardevCommon *backend, Error **errp);
 129
 130 /**
 131  * @qemu_chr_new_from_opts:
 132  *
 133  * Create a new character backend from a QemuOpts list.
 134  *
 135  * @opts see qemu-config.c for a list of valid options
 136  *
 137  * Returns: a new character backend
 138  */
 139 CharDriverState *qemu_chr_new_from_opts(QemuOpts *opts,
 140                                         Error **errp);
 141
 142 /**
 143  * @qemu_chr_parse_common:
 144  *
 145  * Parse the common options available to all character backends.
 146  *
 147  * @opts the options that still need parsing
 148  * @backend a new backend
 149  */
 150 void qemu_chr_parse_common(QemuOpts *opts, ChardevCommon *backend);
 151
 152 /**
 153  * @qemu_chr_new:
 154  *
 155  * Create a new character backend from a URI.
 156  *
 157  * @label the name of the backend
 158  * @filename the URI
 159  *
 160  * Returns: a new character backend
 161  */
 162 CharDriverState *qemu_chr_new(const char *label, const char *filename);
 163
 164
 165 /**
 166  * @qemu_chr_fe_disconnect:
 167  *
 168  * Close a fd accpeted by character backend.
 169  * Without associated CharDriver, do nothing.
 170  */
 171 void qemu_chr_fe_disconnect(CharBackend *be);
 172
 173 /**
 174  * @qemu_chr_cleanup:
 175  *
 176  * Delete all chardevs (when leaving qemu)
 177  */
 178 void qemu_chr_cleanup(void);
 179
 180 /**
 181  * @qemu_chr_fe_wait_connected:
 182  *
 183  * Wait for characted backend to be connected, return < 0 on error or
 184  * if no assicated CharDriver.
 185  */
 186 int qemu_chr_fe_wait_connected(CharBackend *be, Error **errp);
 187
 188 /**
 189  * @qemu_chr_new_noreplay:
 190  *
 191  * Create a new character backend from a URI.
 192  * Character device communications are not written
 193  * into the replay log.
 194  *
 195  * @label the name of the backend
 196  * @filename the URI
 197  *
 198  * Returns: a new character backend
 199  */
 200 CharDriverState *qemu_chr_new_noreplay(const char *label, const char *filename);
 201
 202 /**
 203  * @qemu_chr_delete:
 204  *
 205  * Destroy a character backend and remove it from the list of
 206  * identified character backends.
 207  */
 208 void qemu_chr_delete(CharDriverState *chr);
 209
 210 /**
 211  * @qemu_chr_free:
 212  *
 213  * Destroy a character backend.
 214  */
 215 void qemu_chr_free(CharDriverState *chr);
 216
 217 /**
 218  * @qemu_chr_fe_set_echo:
 219  *
 220  * Ask the backend to override its normal echo setting.  This only really
 221  * applies to the stdio backend and is used by the QMP server such that you
 222  * can see what you type if you try to type QMP commands.
 223  * Without associated CharDriver, do nothing.
 224  *
 225  * @echo true to enable echo, false to disable echo
 226  */
 227 void qemu_chr_fe_set_echo(CharBackend *be, bool echo);
 228
 229 /**
 230  * @qemu_chr_fe_set_open:
 231  *
 232  * Set character frontend open status.  This is an indication that the
 233  * front end is ready (or not) to begin doing I/O.
 234  * Without associated CharDriver, do nothing.
 235  */
 236 void qemu_chr_fe_set_open(CharBackend *be, int fe_open);
 237
 238 /**
 239  * @qemu_chr_fe_printf:
 240  *
 241  * Write to a character backend using a printf style interface.  This
 242  * function is thread-safe. It does nothing without associated
 243  * CharDriver.
 244  *
 245  * @fmt see #printf
 246  */
 247 void qemu_chr_fe_printf(CharBackend *be, const char *fmt, ...)
 248     GCC_FMT_ATTR(2, 3);
 249
 250 /**
 251  * @qemu_chr_fe_add_watch:
 252  *
 253  * If the backend is connected, create and add a #GSource that fires
 254  * when the given condition (typically G_IO_OUT|G_IO_HUP or G_IO_HUP)
 255  * is active; return the #GSource's tag.  If it is disconnected,
 256  * or without associated CharDriver, return 0.
 257  *
 258  * @cond the condition to poll for
 259  * @func the function to call when the condition happens
 260  * @user_data the opaque pointer to pass to @func
 261  *
 262  * Returns: the source tag
 263  */
 264 guint qemu_chr_fe_add_watch(CharBackend *be, GIOCondition cond,
 265                             GIOFunc func, void *user_data);
 266
 267 /**
 268  * @qemu_chr_fe_write:
 269  *
 270  * Write data to a character backend from the front end.  This function
 271  * will send data from the front end to the back end.  This function
 272  * is thread-safe.
 273  *
 274  * @buf the data
 275  * @len the number of bytes to send
 276  *
 277  * Returns: the number of bytes consumed (0 if no assicated CharDriver)
 278  */
 279 int qemu_chr_fe_write(CharBackend *be, const uint8_t *buf, int len);
 280
 281 /**
 282  * @qemu_chr_fe_write_all:
 283  *
 284  * Write data to a character backend from the front end.  This function will
 285  * send data from the front end to the back end.  Unlike @qemu_chr_fe_write,
 286  * this function will block if the back end cannot consume all of the data
 287  * attempted to be written.  This function is thread-safe.
 288  *
 289  * @buf the data
 290  * @len the number of bytes to send
 291  *
 292  * Returns: the number of bytes consumed (0 if no assicated CharDriver)
 293  */
 294 int qemu_chr_fe_write_all(CharBackend *be, const uint8_t *buf, int len);
 295
 296 /**
 297  * @qemu_chr_fe_read_all:
 298  *
 299  * Read data to a buffer from the back end.
 300  *
 301  * @buf the data buffer
 302  * @len the number of bytes to read
 303  *
 304  * Returns: the number of bytes read (0 if no assicated CharDriver)
 305  */
 306 int qemu_chr_fe_read_all(CharBackend *be, uint8_t *buf, int len);
 307
 308 /**
 309  * @qemu_chr_fe_ioctl:
 310  *
 311  * Issue a device specific ioctl to a backend.  This function is thread-safe.
 312  *
 313  * @cmd see CHR_IOCTL_*
 314  * @arg the data associated with @cmd
 315  *
 316  * Returns: if @cmd is not supported by the backend or there is no
 317  *          associated CharDriver, -ENOTSUP, otherwise the return
 318  *          value depends on the semantics of @cmd
 319  */
 320 int qemu_chr_fe_ioctl(CharBackend *be, int cmd, void *arg);
 321
 322 /**
 323  * @qemu_chr_fe_get_msgfd:
 324  *
 325  * For backends capable of fd passing, return the latest file descriptor passed
 326  * by a client.
 327  *
 328  * Returns: -1 if fd passing isn't supported or there is no pending file
 329  *          descriptor.  If a file descriptor is returned, subsequent calls to
 330  *          this function will return -1 until a client sends a new file
 331  *          descriptor.
 332  */
 333 int qemu_chr_fe_get_msgfd(CharBackend *be);
 334
 335 /**
 336  * @qemu_chr_fe_get_msgfds:
 337  *
 338  * For backends capable of fd passing, return the number of file received
 339  * descriptors and fills the fds array up to num elements
 340  *
 341  * Returns: -1 if fd passing isn't supported or there are no pending file
 342  *          descriptors.  If file descriptors are returned, subsequent calls to
 343  *          this function will return -1 until a client sends a new set of file
 344  *          descriptors.
 345  */
 346 int qemu_chr_fe_get_msgfds(CharBackend *be, int *fds, int num);
 347
 348 /**
 349  * @qemu_chr_fe_set_msgfds:
 350  *
 351  * For backends capable of fd passing, set an array of fds to be passed with
 352  * the next send operation.
 353  * A subsequent call to this function before calling a write function will
 354  * result in overwriting the fd array with the new value without being send.
 355  * Upon writing the message the fd array is freed.
 356  *
 357  * Returns: -1 if fd passing isn't supported or no associated CharDriver.
 358  */
 359 int qemu_chr_fe_set_msgfds(CharBackend *be, int *fds, int num);
 360
 361 /**
 362  * @qemu_chr_be_can_write:
 363  *
 364  * Determine how much data the front end can currently accept.  This function
 365  * returns the number of bytes the front end can accept.  If it returns 0, the
 366  * front end cannot receive data at the moment.  The function must be polled
 367  * to determine when data can be received.
 368  *
 369  * Returns: the number of bytes the front end can receive via @qemu_chr_be_write
 370  */
 371 int qemu_chr_be_can_write(CharDriverState *s);
 372
 373 /**
 374  * @qemu_chr_be_write:
 375  *
 376  * Write data from the back end to the front end.  Before issuing this call,
 377  * the caller should call @qemu_chr_be_can_write to determine how much data
 378  * the front end can currently accept.
 379  *
 380  * @buf a buffer to receive data from the front end
 381  * @len the number of bytes to receive from the front end
 382  */
 383 void qemu_chr_be_write(CharDriverState *s, uint8_t *buf, int len);
 384
 385 /**
 386  * @qemu_chr_be_write_impl:
 387  *
 388  * Implementation of back end writing. Used by replay module.
 389  *
 390  * @buf a buffer to receive data from the front end
 391  * @len the number of bytes to receive from the front end
 392  */
 393 void qemu_chr_be_write_impl(CharDriverState *s, uint8_t *buf, int len);
 394
 395 /**
 396  * @qemu_chr_be_event:
 397  *
 398  * Send an event from the back end to the front end.
 399  *
 400  * @event the event to send
 401  */
 402 void qemu_chr_be_event(CharDriverState *s, int event);
 403
 404 /**
 405  * @qemu_chr_fe_init:
 406  *
 407  * Initializes a front end for the given CharBackend and
 408  * CharDriver. Call qemu_chr_fe_deinit() to remove the association and
 409  * release the driver.
 410  *
 411  * Returns: false on error.
 412  */
 413 bool qemu_chr_fe_init(CharBackend *b, CharDriverState *s, Error **errp);
 414
 415 /**
 416  * @qemu_chr_fe_get_driver:
 417  *
 418  * Returns the driver associated with a CharBackend or NULL if no
 419  * associated CharDriver.
 420  */
 421 CharDriverState *qemu_chr_fe_get_driver(CharBackend *be);
 422
 423 /**
 424  * @qemu_chr_fe_deinit:
 425  *
 426  * Dissociate the CharBackend from the CharDriver.
 427  *
 428  * Safe to call without associated CharDriver.
 429  */
 430 void qemu_chr_fe_deinit(CharBackend *b);
 431
 432 /**
 433  * @qemu_chr_fe_set_handlers:
 434  * @b: a CharBackend
 435  * @fd_can_read: callback to get the amount of data the frontend may
 436  *               receive
 437  * @fd_read: callback to receive data from char
 438  * @fd_event: event callback
 439  * @opaque: an opaque pointer for the callbacks
 440  * @context: a main loop context or NULL for the default
 441  * @set_open: whether to call qemu_chr_fe_set_open() implicitely when
 442  * any of the handler is non-NULL
 443  *
 444  * Set the front end char handlers. The front end takes the focus if
 445  * any of the handler is non-NULL.
 446  *
 447  * Without associated CharDriver, nothing is changed.
 448  */
 449 void qemu_chr_fe_set_handlers(CharBackend *b,
 450                               IOCanReadHandler *fd_can_read,
 451                               IOReadHandler *fd_read,
 452                               IOEventHandler *fd_event,
 453                               void *opaque,
 454                               GMainContext *context,
 455                               bool set_open);
 456
 457 /**
 458  * @qemu_chr_fe_take_focus:
 459  *
 460  * Take the focus (if the front end is muxed).
 461  *
 462  * Without associated CharDriver, nothing is changed.
 463  */
 464 void qemu_chr_fe_take_focus(CharBackend *b);
 465
 466 void qemu_chr_be_generic_open(CharDriverState *s);
 467 void qemu_chr_fe_accept_input(CharBackend *be);
 468 int qemu_chr_add_client(CharDriverState *s, int fd);
 469 CharDriverState *qemu_chr_find(const char *name);
 470 bool chr_is_ringbuf(const CharDriverState *chr);
 471
 472 bool qemu_chr_has_feature(CharDriverState *chr,
 473                           CharDriverFeature feature);
 474 void qemu_chr_set_feature(CharDriverState *chr,
 475                           CharDriverFeature feature);
 476 QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename);
 477
 478 typedef struct CharDriver {
 479     ChardevBackendKind kind;
 480     const char *alias;
 481     void (*parse)(QemuOpts *opts, ChardevBackend *backend, Error **errp);
 482     CharDriverState *(*create)(const char *id,
 483                                ChardevBackend *backend,
 484                                ChardevReturn *ret, bool *be_opened,
 485                                Error **errp);
 486 } CharDriver;
 487
 488 void register_char_driver(const CharDriver *driver);
 489
 490 extern int term_escape_char;
 491
 492
 493 /* console.c */
 494 typedef CharDriverState *(VcHandler)(ChardevVC *vc, Error **errp);
 495 void register_vc_handler(VcHandler *handler);
 496
 497 #endif