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 typedef struct CharDriver CharDriver;
  89
  90 struct CharDriverState {
  91     const CharDriver *driver;
  92     QemuMutex chr_write_lock;
  93     CharBackend *be;
  94     void *opaque;
  95     char *label;
  96     char *filename;
  97     int logfd;
  98     int be_open;
  99     int is_mux;
 100     guint fd_in_tag;
 101     bool replay;
 102     DECLARE_BITMAP(features, QEMU_CHAR_FEATURE_LAST);
 103     QTAILQ_ENTRY(CharDriverState) next;
 104 };
 105
 106 /**
 107  * qemu_chr_alloc:
 108  * @backend: the common backend config
 109  * @errp: pointer to a NULL-initialized error object
 110  *
 111  * Allocate and initialize a new CharDriverState.
 112  *
 113  * Returns: a newly allocated CharDriverState, or NULL on error.
 114  */
 115 CharDriverState *qemu_chr_alloc(const CharDriver *driver,
 116                                 ChardevCommon *backend, Error **errp);
 117
 118 /**
 119  * @qemu_chr_new_from_opts:
 120  *
 121  * Create a new character backend from a QemuOpts list.
 122  *
 123  * @opts see qemu-config.c for a list of valid options
 124  *
 125  * Returns: a new character backend
 126  */
 127 CharDriverState *qemu_chr_new_from_opts(QemuOpts *opts,
 128                                         Error **errp);
 129
 130 /**
 131  * @qemu_chr_parse_common:
 132  *
 133  * Parse the common options available to all character backends.
 134  *
 135  * @opts the options that still need parsing
 136  * @backend a new backend
 137  */
 138 void qemu_chr_parse_common(QemuOpts *opts, ChardevCommon *backend);
 139
 140 /**
 141  * @qemu_chr_new:
 142  *
 143  * Create a new character backend from a URI.
 144  *
 145  * @label the name of the backend
 146  * @filename the URI
 147  *
 148  * Returns: a new character backend
 149  */
 150 CharDriverState *qemu_chr_new(const char *label, const char *filename);
 151
 152
 153 /**
 154  * @qemu_chr_fe_disconnect:
 155  *
 156  * Close a fd accpeted by character backend.
 157  * Without associated CharDriver, do nothing.
 158  */
 159 void qemu_chr_fe_disconnect(CharBackend *be);
 160
 161 /**
 162  * @qemu_chr_cleanup:
 163  *
 164  * Delete all chardevs (when leaving qemu)
 165  */
 166 void qemu_chr_cleanup(void);
 167
 168 /**
 169  * @qemu_chr_fe_wait_connected:
 170  *
 171  * Wait for characted backend to be connected, return < 0 on error or
 172  * if no assicated CharDriver.
 173  */
 174 int qemu_chr_fe_wait_connected(CharBackend *be, Error **errp);
 175
 176 /**
 177  * @qemu_chr_new_noreplay:
 178  *
 179  * Create a new character backend from a URI.
 180  * Character device communications are not written
 181  * into the replay log.
 182  *
 183  * @label the name of the backend
 184  * @filename the URI
 185  *
 186  * Returns: a new character backend
 187  */
 188 CharDriverState *qemu_chr_new_noreplay(const char *label, const char *filename);
 189
 190 /**
 191  * @qemu_chr_delete:
 192  *
 193  * Destroy a character backend and remove it from the list of
 194  * identified character backends.
 195  */
 196 void qemu_chr_delete(CharDriverState *chr);
 197
 198 /**
 199  * @qemu_chr_free:
 200  *
 201  * Destroy a character backend.
 202  */
 203 void qemu_chr_free(CharDriverState *chr);
 204
 205 /**
 206  * @qemu_chr_fe_set_echo:
 207  *
 208  * Ask the backend to override its normal echo setting.  This only really
 209  * applies to the stdio backend and is used by the QMP server such that you
 210  * can see what you type if you try to type QMP commands.
 211  * Without associated CharDriver, do nothing.
 212  *
 213  * @echo true to enable echo, false to disable echo
 214  */
 215 void qemu_chr_fe_set_echo(CharBackend *be, bool echo);
 216
 217 /**
 218  * @qemu_chr_fe_set_open:
 219  *
 220  * Set character frontend open status.  This is an indication that the
 221  * front end is ready (or not) to begin doing I/O.
 222  * Without associated CharDriver, do nothing.
 223  */
 224 void qemu_chr_fe_set_open(CharBackend *be, int fe_open);
 225
 226 /**
 227  * @qemu_chr_fe_printf:
 228  *
 229  * Write to a character backend using a printf style interface.  This
 230  * function is thread-safe. It does nothing without associated
 231  * CharDriver.
 232  *
 233  * @fmt see #printf
 234  */
 235 void qemu_chr_fe_printf(CharBackend *be, const char *fmt, ...)
 236     GCC_FMT_ATTR(2, 3);
 237
 238 /**
 239  * @qemu_chr_fe_add_watch:
 240  *
 241  * If the backend is connected, create and add a #GSource that fires
 242  * when the given condition (typically G_IO_OUT|G_IO_HUP or G_IO_HUP)
 243  * is active; return the #GSource's tag.  If it is disconnected,
 244  * or without associated CharDriver, return 0.
 245  *
 246  * @cond the condition to poll for
 247  * @func the function to call when the condition happens
 248  * @user_data the opaque pointer to pass to @func
 249  *
 250  * Returns: the source tag
 251  */
 252 guint qemu_chr_fe_add_watch(CharBackend *be, GIOCondition cond,
 253                             GIOFunc func, void *user_data);
 254
 255 /**
 256  * @qemu_chr_fe_write:
 257  *
 258  * Write data to a character backend from the front end.  This function
 259  * will send data from the front end to the back end.  This function
 260  * is thread-safe.
 261  *
 262  * @buf the data
 263  * @len the number of bytes to send
 264  *
 265  * Returns: the number of bytes consumed (0 if no assicated CharDriver)
 266  */
 267 int qemu_chr_fe_write(CharBackend *be, const uint8_t *buf, int len);
 268
 269 /**
 270  * @qemu_chr_fe_write_all:
 271  *
 272  * Write data to a character backend from the front end.  This function will
 273  * send data from the front end to the back end.  Unlike @qemu_chr_fe_write,
 274  * this function will block if the back end cannot consume all of the data
 275  * attempted to be written.  This function is thread-safe.
 276  *
 277  * @buf the data
 278  * @len the number of bytes to send
 279  *
 280  * Returns: the number of bytes consumed (0 if no assicated CharDriver)
 281  */
 282 int qemu_chr_fe_write_all(CharBackend *be, const uint8_t *buf, int len);
 283
 284 /**
 285  * @qemu_chr_fe_read_all:
 286  *
 287  * Read data to a buffer from the back end.
 288  *
 289  * @buf the data buffer
 290  * @len the number of bytes to read
 291  *
 292  * Returns: the number of bytes read (0 if no assicated CharDriver)
 293  */
 294 int qemu_chr_fe_read_all(CharBackend *be, uint8_t *buf, int len);
 295
 296 /**
 297  * @qemu_chr_fe_ioctl:
 298  *
 299  * Issue a device specific ioctl to a backend.  This function is thread-safe.
 300  *
 301  * @cmd see CHR_IOCTL_*
 302  * @arg the data associated with @cmd
 303  *
 304  * Returns: if @cmd is not supported by the backend or there is no
 305  *          associated CharDriver, -ENOTSUP, otherwise the return
 306  *          value depends on the semantics of @cmd
 307  */
 308 int qemu_chr_fe_ioctl(CharBackend *be, int cmd, void *arg);
 309
 310 /**
 311  * @qemu_chr_fe_get_msgfd:
 312  *
 313  * For backends capable of fd passing, return the latest file descriptor passed
 314  * by a client.
 315  *
 316  * Returns: -1 if fd passing isn't supported or there is no pending file
 317  *          descriptor.  If a file descriptor is returned, subsequent calls to
 318  *          this function will return -1 until a client sends a new file
 319  *          descriptor.
 320  */
 321 int qemu_chr_fe_get_msgfd(CharBackend *be);
 322
 323 /**
 324  * @qemu_chr_fe_get_msgfds:
 325  *
 326  * For backends capable of fd passing, return the number of file received
 327  * descriptors and fills the fds array up to num elements
 328  *
 329  * Returns: -1 if fd passing isn't supported or there are no pending file
 330  *          descriptors.  If file descriptors are returned, subsequent calls to
 331  *          this function will return -1 until a client sends a new set of file
 332  *          descriptors.
 333  */
 334 int qemu_chr_fe_get_msgfds(CharBackend *be, int *fds, int num);
 335
 336 /**
 337  * @qemu_chr_fe_set_msgfds:
 338  *
 339  * For backends capable of fd passing, set an array of fds to be passed with
 340  * the next send operation.
 341  * A subsequent call to this function before calling a write function will
 342  * result in overwriting the fd array with the new value without being send.
 343  * Upon writing the message the fd array is freed.
 344  *
 345  * Returns: -1 if fd passing isn't supported or no associated CharDriver.
 346  */
 347 int qemu_chr_fe_set_msgfds(CharBackend *be, int *fds, int num);
 348
 349 /**
 350  * @qemu_chr_be_can_write:
 351  *
 352  * Determine how much data the front end can currently accept.  This function
 353  * returns the number of bytes the front end can accept.  If it returns 0, the
 354  * front end cannot receive data at the moment.  The function must be polled
 355  * to determine when data can be received.
 356  *
 357  * Returns: the number of bytes the front end can receive via @qemu_chr_be_write
 358  */
 359 int qemu_chr_be_can_write(CharDriverState *s);
 360
 361 /**
 362  * @qemu_chr_be_write:
 363  *
 364  * Write data from the back end to the front end.  Before issuing this call,
 365  * the caller should call @qemu_chr_be_can_write to determine how much data
 366  * the front end can currently accept.
 367  *
 368  * @buf a buffer to receive data from the front end
 369  * @len the number of bytes to receive from the front end
 370  */
 371 void qemu_chr_be_write(CharDriverState *s, uint8_t *buf, int len);
 372
 373 /**
 374  * @qemu_chr_be_write_impl:
 375  *
 376  * Implementation of back end writing. Used by replay module.
 377  *
 378  * @buf a buffer to receive data from the front end
 379  * @len the number of bytes to receive from the front end
 380  */
 381 void qemu_chr_be_write_impl(CharDriverState *s, uint8_t *buf, int len);
 382
 383 /**
 384  * @qemu_chr_be_event:
 385  *
 386  * Send an event from the back end to the front end.
 387  *
 388  * @event the event to send
 389  */
 390 void qemu_chr_be_event(CharDriverState *s, int event);
 391
 392 /**
 393  * @qemu_chr_fe_init:
 394  *
 395  * Initializes a front end for the given CharBackend and
 396  * CharDriver. Call qemu_chr_fe_deinit() to remove the association and
 397  * release the driver.
 398  *
 399  * Returns: false on error.
 400  */
 401 bool qemu_chr_fe_init(CharBackend *b, CharDriverState *s, Error **errp);
 402
 403 /**
 404  * @qemu_chr_fe_get_driver:
 405  *
 406  * Returns the driver associated with a CharBackend or NULL if no
 407  * associated CharDriver.
 408  */
 409 CharDriverState *qemu_chr_fe_get_driver(CharBackend *be);
 410
 411 /**
 412  * @qemu_chr_fe_deinit:
 413  *
 414  * Dissociate the CharBackend from the CharDriver.
 415  *
 416  * Safe to call without associated CharDriver.
 417  */
 418 void qemu_chr_fe_deinit(CharBackend *b);
 419
 420 /**
 421  * @qemu_chr_fe_set_handlers:
 422  * @b: a CharBackend
 423  * @fd_can_read: callback to get the amount of data the frontend may
 424  *               receive
 425  * @fd_read: callback to receive data from char
 426  * @fd_event: event callback
 427  * @opaque: an opaque pointer for the callbacks
 428  * @context: a main loop context or NULL for the default
 429  * @set_open: whether to call qemu_chr_fe_set_open() implicitely when
 430  * any of the handler is non-NULL
 431  *
 432  * Set the front end char handlers. The front end takes the focus if
 433  * any of the handler is non-NULL.
 434  *
 435  * Without associated CharDriver, nothing is changed.
 436  */
 437 void qemu_chr_fe_set_handlers(CharBackend *b,
 438                               IOCanReadHandler *fd_can_read,
 439                               IOReadHandler *fd_read,
 440                               IOEventHandler *fd_event,
 441                               void *opaque,
 442                               GMainContext *context,
 443                               bool set_open);
 444
 445 /**
 446  * @qemu_chr_fe_take_focus:
 447  *
 448  * Take the focus (if the front end is muxed).
 449  *
 450  * Without associated CharDriver, nothing is changed.
 451  */
 452 void qemu_chr_fe_take_focus(CharBackend *b);
 453
 454 void qemu_chr_be_generic_open(CharDriverState *s);
 455 void qemu_chr_fe_accept_input(CharBackend *be);
 456 int qemu_chr_add_client(CharDriverState *s, int fd);
 457 CharDriverState *qemu_chr_find(const char *name);
 458 bool chr_is_ringbuf(const CharDriverState *chr);
 459
 460 bool qemu_chr_has_feature(CharDriverState *chr,
 461                           CharDriverFeature feature);
 462 void qemu_chr_set_feature(CharDriverState *chr,
 463                           CharDriverFeature feature);
 464 QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename);
 465
 466 struct CharDriver {
 467     ChardevBackendKind kind;
 468     const char *alias;
 469     void (*parse)(QemuOpts *opts, ChardevBackend *backend, Error **errp);
 470     CharDriverState *(*create)(const CharDriver *driver,
 471                                const char *id,
 472                                ChardevBackend *backend,
 473                                ChardevReturn *ret, bool *be_opened,
 474                                Error **errp);
 475
 476     int (*chr_write)(struct CharDriverState *s, const uint8_t *buf, int len);
 477     int (*chr_sync_read)(struct CharDriverState *s,
 478                          const uint8_t *buf, int len);
 479     GSource *(*chr_add_watch)(struct CharDriverState *s, GIOCondition cond);
 480     void (*chr_update_read_handler)(struct CharDriverState *s,
 481                                     GMainContext *context);
 482     int (*chr_ioctl)(struct CharDriverState *s, int cmd, void *arg);
 483     int (*get_msgfds)(struct CharDriverState *s, int* fds, int num);
 484     int (*set_msgfds)(struct CharDriverState *s, int *fds, int num);
 485     int (*chr_add_client)(struct CharDriverState *chr, int fd);
 486     int (*chr_wait_connected)(struct CharDriverState *chr, Error **errp);
 487     void (*chr_free)(struct CharDriverState *chr);
 488     void (*chr_disconnect)(struct CharDriverState *chr);
 489     void (*chr_accept_input)(struct CharDriverState *chr);
 490     void (*chr_set_echo)(struct CharDriverState *chr, bool echo);
 491     void (*chr_set_fe_open)(struct CharDriverState *chr, int fe_open);
 492 };
 493
 494 void register_char_driver(const CharDriver *driver);
 495
 496 extern int term_escape_char;
 497
 498
 499 /* console.c */
 500 typedef CharDriverState *(VcHandler)(ChardevVC *vc, Error **errp);
 501 void register_vc_handler(VcHandler *handler);
 502
 503 #endif