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 #include "qom/object.h"
  14
  15 /* character device */
  16
  17 typedef enum {
  18     CHR_EVENT_BREAK, /* serial break char */
  19     CHR_EVENT_OPENED, /* new connection established */
  20     CHR_EVENT_MUX_IN, /* mux-focus was set to this terminal */
  21     CHR_EVENT_MUX_OUT, /* mux-focus will move on */
  22     CHR_EVENT_CLOSED /* connection closed */
  23 } QEMUChrEvent;
  24
  25
  26 #define CHR_IOCTL_SERIAL_SET_PARAMS   1
  27 typedef struct {
  28     int speed;
  29     int parity;
  30     int data_bits;
  31     int stop_bits;
  32 } QEMUSerialSetParams;
  33
  34 #define CHR_IOCTL_SERIAL_SET_BREAK    2
  35
  36 #define CHR_IOCTL_PP_READ_DATA        3
  37 #define CHR_IOCTL_PP_WRITE_DATA       4
  38 #define CHR_IOCTL_PP_READ_CONTROL     5
  39 #define CHR_IOCTL_PP_WRITE_CONTROL    6
  40 #define CHR_IOCTL_PP_READ_STATUS      7
  41 #define CHR_IOCTL_PP_EPP_READ_ADDR    8
  42 #define CHR_IOCTL_PP_EPP_READ         9
  43 #define CHR_IOCTL_PP_EPP_WRITE_ADDR  10
  44 #define CHR_IOCTL_PP_EPP_WRITE       11
  45 #define CHR_IOCTL_PP_DATA_DIR        12
  46
  47 struct ParallelIOArg {
  48     void *buffer;
  49     int count;
  50 };
  51
  52 #define CHR_IOCTL_SERIAL_SET_TIOCM   13
  53 #define CHR_IOCTL_SERIAL_GET_TIOCM   14
  54
  55 #define CHR_TIOCM_CTS   0x020
  56 #define CHR_TIOCM_CAR   0x040
  57 #define CHR_TIOCM_DSR   0x100
  58 #define CHR_TIOCM_RI    0x080
  59 #define CHR_TIOCM_DTR   0x002
  60 #define CHR_TIOCM_RTS   0x004
  61
  62 typedef void IOEventHandler(void *opaque, int event);
  63
  64 typedef enum {
  65     /* Whether the chardev peer is able to close and
  66      * reopen the data channel, thus requiring support
  67      * for qemu_chr_wait_connected() to wait for a
  68      * valid connection */
  69     QEMU_CHAR_FEATURE_RECONNECTABLE,
  70     /* Whether it is possible to send/recv file descriptors
  71      * over the data channel */
  72     QEMU_CHAR_FEATURE_FD_PASS,
  73     /* Whether replay or record mode is enabled */
  74     QEMU_CHAR_FEATURE_REPLAY,
  75
  76     QEMU_CHAR_FEATURE_LAST,
  77 } ChardevFeature;
  78
  79 /* This is the backend as seen by frontend, the actual backend is
  80  * Chardev */
  81 typedef struct CharBackend {
  82     Chardev *chr;
  83     IOEventHandler *chr_event;
  84     IOCanReadHandler *chr_can_read;
  85     IOReadHandler *chr_read;
  86     void *opaque;
  87     int tag;
  88     int fe_open;
  89 } CharBackend;
  90
  91 struct Chardev {
  92     Object parent_obj;
  93
  94     QemuMutex chr_write_lock;
  95     CharBackend *be;
  96     char *label;
  97     char *filename;
  98     int logfd;
  99     int be_open;
 100     guint fd_in_tag;
 101     DECLARE_BITMAP(features, QEMU_CHAR_FEATURE_LAST);
 102     QTAILQ_ENTRY(Chardev) next;
 103 };
 104
 105 /**
 106  * @qemu_chr_new_from_opts:
 107  *
 108  * Create a new character backend from a QemuOpts list.
 109  *
 110  * @opts see qemu-config.c for a list of valid options
 111  *
 112  * Returns: a new character backend
 113  */
 114 Chardev *qemu_chr_new_from_opts(QemuOpts *opts,
 115                                 Error **errp);
 116
 117 /**
 118  * @qemu_chr_parse_common:
 119  *
 120  * Parse the common options available to all character backends.
 121  *
 122  * @opts the options that still need parsing
 123  * @backend a new backend
 124  */
 125 void qemu_chr_parse_common(QemuOpts *opts, ChardevCommon *backend);
 126
 127 /**
 128  * @qemu_chr_new:
 129  *
 130  * Create a new character backend from a URI.
 131  *
 132  * @label the name of the backend
 133  * @filename the URI
 134  *
 135  * Returns: a new character backend
 136  */
 137 Chardev *qemu_chr_new(const char *label, const char *filename);
 138
 139
 140 /**
 141  * @qemu_chr_fe_disconnect:
 142  *
 143  * Close a fd accpeted by character backend.
 144  * Without associated Chardev, do nothing.
 145  */
 146 void qemu_chr_fe_disconnect(CharBackend *be);
 147
 148 /**
 149  * @qemu_chr_cleanup:
 150  *
 151  * Delete all chardevs (when leaving qemu)
 152  */
 153 void qemu_chr_cleanup(void);
 154
 155 /**
 156  * @qemu_chr_fe_wait_connected:
 157  *
 158  * Wait for characted backend to be connected, return < 0 on error or
 159  * if no assicated Chardev.
 160  */
 161 int qemu_chr_fe_wait_connected(CharBackend *be, Error **errp);
 162
 163 /**
 164  * @qemu_chr_new_noreplay:
 165  *
 166  * Create a new character backend from a URI.
 167  * Character device communications are not written
 168  * into the replay log.
 169  *
 170  * @label the name of the backend
 171  * @filename the URI
 172  *
 173  * Returns: a new character backend
 174  */
 175 Chardev *qemu_chr_new_noreplay(const char *label, const char *filename);
 176
 177 /**
 178  * @qemu_chr_delete:
 179  *
 180  * Destroy a character backend and remove it from the list of
 181  * identified character backends.
 182  */
 183 void qemu_chr_delete(Chardev *chr);
 184
 185 /**
 186  * @qemu_chr_fe_set_echo:
 187  *
 188  * Ask the backend to override its normal echo setting.  This only really
 189  * applies to the stdio backend and is used by the QMP server such that you
 190  * can see what you type if you try to type QMP commands.
 191  * Without associated Chardev, do nothing.
 192  *
 193  * @echo true to enable echo, false to disable echo
 194  */
 195 void qemu_chr_fe_set_echo(CharBackend *be, bool echo);
 196
 197 /**
 198  * @qemu_chr_fe_set_open:
 199  *
 200  * Set character frontend open status.  This is an indication that the
 201  * front end is ready (or not) to begin doing I/O.
 202  * Without associated Chardev, do nothing.
 203  */
 204 void qemu_chr_fe_set_open(CharBackend *be, int fe_open);
 205
 206 /**
 207  * @qemu_chr_fe_printf:
 208  *
 209  * Write to a character backend using a printf style interface.  This
 210  * function is thread-safe. It does nothing without associated
 211  * Chardev.
 212  *
 213  * @fmt see #printf
 214  */
 215 void qemu_chr_fe_printf(CharBackend *be, const char *fmt, ...)
 216     GCC_FMT_ATTR(2, 3);
 217
 218 /**
 219  * @qemu_chr_fe_add_watch:
 220  *
 221  * If the backend is connected, create and add a #GSource that fires
 222  * when the given condition (typically G_IO_OUT|G_IO_HUP or G_IO_HUP)
 223  * is active; return the #GSource's tag.  If it is disconnected,
 224  * or without associated Chardev, return 0.
 225  *
 226  * @cond the condition to poll for
 227  * @func the function to call when the condition happens
 228  * @user_data the opaque pointer to pass to @func
 229  *
 230  * Returns: the source tag
 231  */
 232 guint qemu_chr_fe_add_watch(CharBackend *be, GIOCondition cond,
 233                             GIOFunc func, void *user_data);
 234
 235 /**
 236  * @qemu_chr_fe_write:
 237  *
 238  * Write data to a character backend from the front end.  This function
 239  * will send data from the front end to the back end.  This function
 240  * is thread-safe.
 241  *
 242  * @buf the data
 243  * @len the number of bytes to send
 244  *
 245  * Returns: the number of bytes consumed (0 if no assicated Chardev)
 246  */
 247 int qemu_chr_fe_write(CharBackend *be, const uint8_t *buf, int len);
 248
 249 /**
 250  * @qemu_chr_fe_write_all:
 251  *
 252  * Write data to a character backend from the front end.  This function will
 253  * send data from the front end to the back end.  Unlike @qemu_chr_fe_write,
 254  * this function will block if the back end cannot consume all of the data
 255  * attempted to be written.  This function is thread-safe.
 256  *
 257  * @buf the data
 258  * @len the number of bytes to send
 259  *
 260  * Returns: the number of bytes consumed (0 if no assicated Chardev)
 261  */
 262 int qemu_chr_fe_write_all(CharBackend *be, const uint8_t *buf, int len);
 263
 264 /**
 265  * @qemu_chr_fe_read_all:
 266  *
 267  * Read data to a buffer from the back end.
 268  *
 269  * @buf the data buffer
 270  * @len the number of bytes to read
 271  *
 272  * Returns: the number of bytes read (0 if no assicated Chardev)
 273  */
 274 int qemu_chr_fe_read_all(CharBackend *be, uint8_t *buf, int len);
 275
 276 /**
 277  * @qemu_chr_fe_ioctl:
 278  *
 279  * Issue a device specific ioctl to a backend.  This function is thread-safe.
 280  *
 281  * @cmd see CHR_IOCTL_*
 282  * @arg the data associated with @cmd
 283  *
 284  * Returns: if @cmd is not supported by the backend or there is no
 285  *          associated Chardev, -ENOTSUP, otherwise the return
 286  *          value depends on the semantics of @cmd
 287  */
 288 int qemu_chr_fe_ioctl(CharBackend *be, int cmd, void *arg);
 289
 290 /**
 291  * @qemu_chr_fe_get_msgfd:
 292  *
 293  * For backends capable of fd passing, return the latest file descriptor passed
 294  * by a client.
 295  *
 296  * Returns: -1 if fd passing isn't supported or there is no pending file
 297  *          descriptor.  If a file descriptor is returned, subsequent calls to
 298  *          this function will return -1 until a client sends a new file
 299  *          descriptor.
 300  */
 301 int qemu_chr_fe_get_msgfd(CharBackend *be);
 302
 303 /**
 304  * @qemu_chr_fe_get_msgfds:
 305  *
 306  * For backends capable of fd passing, return the number of file received
 307  * descriptors and fills the fds array up to num elements
 308  *
 309  * Returns: -1 if fd passing isn't supported or there are no pending file
 310  *          descriptors.  If file descriptors are returned, subsequent calls to
 311  *          this function will return -1 until a client sends a new set of file
 312  *          descriptors.
 313  */
 314 int qemu_chr_fe_get_msgfds(CharBackend *be, int *fds, int num);
 315
 316 /**
 317  * @qemu_chr_fe_set_msgfds:
 318  *
 319  * For backends capable of fd passing, set an array of fds to be passed with
 320  * the next send operation.
 321  * A subsequent call to this function before calling a write function will
 322  * result in overwriting the fd array with the new value without being send.
 323  * Upon writing the message the fd array is freed.
 324  *
 325  * Returns: -1 if fd passing isn't supported or no associated Chardev.
 326  */
 327 int qemu_chr_fe_set_msgfds(CharBackend *be, int *fds, int num);
 328
 329 /**
 330  * @qemu_chr_be_can_write:
 331  *
 332  * Determine how much data the front end can currently accept.  This function
 333  * returns the number of bytes the front end can accept.  If it returns 0, the
 334  * front end cannot receive data at the moment.  The function must be polled
 335  * to determine when data can be received.
 336  *
 337  * Returns: the number of bytes the front end can receive via @qemu_chr_be_write
 338  */
 339 int qemu_chr_be_can_write(Chardev *s);
 340
 341 /**
 342  * @qemu_chr_be_write:
 343  *
 344  * Write data from the back end to the front end.  Before issuing this call,
 345  * the caller should call @qemu_chr_be_can_write to determine how much data
 346  * the front end can currently accept.
 347  *
 348  * @buf a buffer to receive data from the front end
 349  * @len the number of bytes to receive from the front end
 350  */
 351 void qemu_chr_be_write(Chardev *s, uint8_t *buf, int len);
 352
 353 /**
 354  * @qemu_chr_be_write_impl:
 355  *
 356  * Implementation of back end writing. Used by replay module.
 357  *
 358  * @buf a buffer to receive data from the front end
 359  * @len the number of bytes to receive from the front end
 360  */
 361 void qemu_chr_be_write_impl(Chardev *s, uint8_t *buf, int len);
 362
 363 /**
 364  * @qemu_chr_be_event:
 365  *
 366  * Send an event from the back end to the front end.
 367  *
 368  * @event the event to send
 369  */
 370 void qemu_chr_be_event(Chardev *s, int event);
 371
 372 /**
 373  * @qemu_chr_fe_init:
 374  *
 375  * Initializes a front end for the given CharBackend and
 376  * Chardev. Call qemu_chr_fe_deinit() to remove the association and
 377  * release the driver.
 378  *
 379  * Returns: false on error.
 380  */
 381 bool qemu_chr_fe_init(CharBackend *b, Chardev *s, Error **errp);
 382
 383 /**
 384  * @qemu_chr_fe_get_driver:
 385  *
 386  * Returns the driver associated with a CharBackend or NULL if no
 387  * associated Chardev.
 388  */
 389 Chardev *qemu_chr_fe_get_driver(CharBackend *be);
 390
 391 /**
 392  * @qemu_chr_fe_deinit:
 393  *
 394  * Dissociate the CharBackend from the Chardev.
 395  *
 396  * Safe to call without associated Chardev.
 397  */
 398 void qemu_chr_fe_deinit(CharBackend *b);
 399
 400 /**
 401  * @qemu_chr_fe_set_handlers:
 402  * @b: a CharBackend
 403  * @fd_can_read: callback to get the amount of data the frontend may
 404  *               receive
 405  * @fd_read: callback to receive data from char
 406  * @fd_event: event callback
 407  * @opaque: an opaque pointer for the callbacks
 408  * @context: a main loop context or NULL for the default
 409  * @set_open: whether to call qemu_chr_fe_set_open() implicitely when
 410  * any of the handler is non-NULL
 411  *
 412  * Set the front end char handlers. The front end takes the focus if
 413  * any of the handler is non-NULL.
 414  *
 415  * Without associated Chardev, nothing is changed.
 416  */
 417 void qemu_chr_fe_set_handlers(CharBackend *b,
 418                               IOCanReadHandler *fd_can_read,
 419                               IOReadHandler *fd_read,
 420                               IOEventHandler *fd_event,
 421                               void *opaque,
 422                               GMainContext *context,
 423                               bool set_open);
 424
 425 /**
 426  * @qemu_chr_fe_take_focus:
 427  *
 428  * Take the focus (if the front end is muxed).
 429  *
 430  * Without associated Chardev, nothing is changed.
 431  */
 432 void qemu_chr_fe_take_focus(CharBackend *b);
 433
 434 void qemu_chr_be_generic_open(Chardev *s);
 435 void qemu_chr_fe_accept_input(CharBackend *be);
 436 int qemu_chr_add_client(Chardev *s, int fd);
 437 Chardev *qemu_chr_find(const char *name);
 438
 439 bool qemu_chr_has_feature(Chardev *chr,
 440                           ChardevFeature feature);
 441 void qemu_chr_set_feature(Chardev *chr,
 442                           ChardevFeature feature);
 443 QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename);
 444 int qemu_chr_write_all(Chardev *s, const uint8_t *buf, int len);
 445
 446 #define TYPE_CHARDEV "chardev"
 447 #define CHARDEV(obj) OBJECT_CHECK(Chardev, (obj), TYPE_CHARDEV)
 448 #define CHARDEV_CLASS(klass) \
 449     OBJECT_CLASS_CHECK(ChardevClass, (klass), TYPE_CHARDEV)
 450 #define CHARDEV_GET_CLASS(obj) \
 451     OBJECT_GET_CLASS(ChardevClass, (obj), TYPE_CHARDEV)
 452
 453 #define TYPE_CHARDEV_NULL "chardev-null"
 454 #define TYPE_CHARDEV_MUX "chardev-mux"
 455 #define TYPE_CHARDEV_RINGBUF "chardev-ringbuf"
 456 #define TYPE_CHARDEV_PTY "chardev-pty"
 457 #define TYPE_CHARDEV_CONSOLE "chardev-console"
 458 #define TYPE_CHARDEV_STDIO "chardev-stdio"
 459 #define TYPE_CHARDEV_PIPE "chardev-pipe"
 460 #define TYPE_CHARDEV_MEMORY "chardev-memory"
 461 #define TYPE_CHARDEV_PARALLEL "chardev-parallel"
 462 #define TYPE_CHARDEV_FILE "chardev-file"
 463 #define TYPE_CHARDEV_SERIAL "chardev-serial"
 464 #define TYPE_CHARDEV_SOCKET "chardev-socket"
 465 #define TYPE_CHARDEV_UDP "chardev-udp"
 466
 467 #define CHARDEV_IS_RINGBUF(chr) \
 468     object_dynamic_cast(OBJECT(chr), TYPE_CHARDEV_RINGBUF)
 469 #define CHARDEV_IS_PTY(chr) \
 470     object_dynamic_cast(OBJECT(chr), TYPE_CHARDEV_PTY)
 471
 472 typedef struct ChardevClass {
 473     ObjectClass parent_class;
 474
 475     bool internal; /* TODO: eventually use TYPE_USER_CREATABLE */
 476     void (*parse)(QemuOpts *opts, ChardevBackend *backend, Error **errp);
 477
 478     void (*open)(Chardev *chr, ChardevBackend *backend,
 479                  bool *be_opened, Error **errp);
 480
 481     int (*chr_write)(Chardev *s, const uint8_t *buf, int len);
 482     int (*chr_sync_read)(Chardev *s, const uint8_t *buf, int len);
 483     GSource *(*chr_add_watch)(Chardev *s, GIOCondition cond);
 484     void (*chr_update_read_handler)(Chardev *s, GMainContext *context);
 485     int (*chr_ioctl)(Chardev *s, int cmd, void *arg);
 486     int (*get_msgfds)(Chardev *s, int* fds, int num);
 487     int (*set_msgfds)(Chardev *s, int *fds, int num);
 488     int (*chr_add_client)(Chardev *chr, int fd);
 489     int (*chr_wait_connected)(Chardev *chr, Error **errp);
 490     void (*chr_disconnect)(Chardev *chr);
 491     void (*chr_accept_input)(Chardev *chr);
 492     void (*chr_set_echo)(Chardev *chr, bool echo);
 493     void (*chr_set_fe_open)(Chardev *chr, int fe_open);
 494 } ChardevClass;
 495
 496 Chardev *qemu_chardev_new(const char *id, const char *typename,
 497                           ChardevBackend *backend, Error **errp);
 498
 499 extern int term_escape_char;
 500
 501 /* console.c */
 502 void qemu_chr_parse_vc(QemuOpts *opts, ChardevBackend *backend, Error **errp);
 503
 504 #endif