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