include/sysemu/char.h

   1 #ifndef QEMU_CHAR_H
   2 #define QEMU_CHAR_H
   3
   4 #include "qemu-common.h"
   5 #include "qemu/option.h"
   6 #include "qemu/main-loop.h"
   7 #include "qemu/bitmap.h"
   8 #include "qom/object.h"
   9
  10 #define IAC_EOR 239
  11 #define IAC_SE 240
  12 #define IAC_NOP 241
  13 #define IAC_BREAK 243
  14 #define IAC_IP 244
  15 #define IAC_SB 250
  16 #define IAC 255
  17
  18 /* character device */
  19
  20 typedef enum {
  21     CHR_EVENT_BREAK, /* serial break char */
  22     CHR_EVENT_OPENED, /* new connection established */
  23     CHR_EVENT_MUX_IN, /* mux-focus was set to this terminal */
  24     CHR_EVENT_MUX_OUT, /* mux-focus will move on */
  25     CHR_EVENT_CLOSED /* connection closed */
  26 } QEMUChrEvent;
  27
  28 #define CHR_READ_BUF_LEN 4096
  29
  30 #define CHR_IOCTL_SERIAL_SET_PARAMS   1
  31 typedef struct {
  32     int speed;
  33     int parity;
  34     int data_bits;
  35     int stop_bits;
  36 } QEMUSerialSetParams;
  37
  38 #define CHR_IOCTL_SERIAL_SET_BREAK    2
  39
  40 #define CHR_IOCTL_PP_READ_DATA        3
  41 #define CHR_IOCTL_PP_WRITE_DATA       4
  42 #define CHR_IOCTL_PP_READ_CONTROL     5
  43 #define CHR_IOCTL_PP_WRITE_CONTROL    6
  44 #define CHR_IOCTL_PP_READ_STATUS      7
  45 #define CHR_IOCTL_PP_EPP_READ_ADDR    8
  46 #define CHR_IOCTL_PP_EPP_READ         9
  47 #define CHR_IOCTL_PP_EPP_WRITE_ADDR  10
  48 #define CHR_IOCTL_PP_EPP_WRITE       11
  49 #define CHR_IOCTL_PP_DATA_DIR        12
  50
  51 struct ParallelIOArg {
  52     void *buffer;
  53     int count;
  54 };
  55
  56 #define CHR_IOCTL_SERIAL_SET_TIOCM   13
  57 #define CHR_IOCTL_SERIAL_GET_TIOCM   14
  58
  59 #define CHR_TIOCM_CTS   0x020
  60 #define CHR_TIOCM_CAR   0x040
  61 #define CHR_TIOCM_DSR   0x100
  62 #define CHR_TIOCM_RI    0x080
  63 #define CHR_TIOCM_DTR   0x002
  64 #define CHR_TIOCM_RTS   0x004
  65
  66 typedef void IOEventHandler(void *opaque, int event);
  67
  68 typedef enum {
  69     /* Whether the chardev peer is able to close and
  70      * reopen the data channel, thus requiring support
  71      * for qemu_chr_wait_connected() to wait for a
  72      * valid connection */
  73     QEMU_CHAR_FEATURE_RECONNECTABLE,
  74     /* Whether it is possible to send/recv file descriptors
  75      * over the data channel */
  76     QEMU_CHAR_FEATURE_FD_PASS,
  77     /* Whether replay or record mode is enabled */
  78     QEMU_CHAR_FEATURE_REPLAY,
  79
  80     QEMU_CHAR_FEATURE_LAST,
  81 } ChardevFeature;
  82
  83 /* This is the backend as seen by frontend, the actual backend is
  84  * Chardev */
  85 typedef struct CharBackend {
  86     Chardev *chr;
  87     IOEventHandler *chr_event;
  88     IOCanReadHandler *chr_can_read;
  89     IOReadHandler *chr_read;
  90     void *opaque;
  91     int tag;
  92     int fe_open;
  93 } CharBackend;
  94
  95 struct Chardev {
  96     Object parent_obj;
  97
  98     QemuMutex chr_write_lock;
  99     CharBackend *be;
 100     char *label;
 101     char *filename;
 102     int logfd;
 103     int be_open;
 104     guint fd_in_tag;
 105     DECLARE_BITMAP(features, QEMU_CHAR_FEATURE_LAST);
 106 };
 107
 108 /**
 109  * @qemu_chr_new_from_opts:
 110  *
 111  * Create a new character backend from a QemuOpts list.
 112  *
 113  * @opts see qemu-config.c for a list of valid options
 114  *
 115  * Returns: a new character backend
 116  */
 117 Chardev *qemu_chr_new_from_opts(QemuOpts *opts,
 118                                 Error **errp);
 119
 120 /**
 121  * @qemu_chr_parse_common:
 122  *
 123  * Parse the common options available to all character backends.
 124  *
 125  * @opts the options that still need parsing
 126  * @backend a new backend
 127  */
 128 void qemu_chr_parse_common(QemuOpts *opts, ChardevCommon *backend);
 129
 130 /**
 131  * @qemu_chr_new:
 132  *
 133  * Create a new character backend from a URI.
 134  *
 135  * @label the name of the backend
 136  * @filename the URI
 137  *
 138  * Returns: a new character backend
 139  */
 140 Chardev *qemu_chr_new(const char *label, const char *filename);
 141
 142
 143 /**
 144  * @qemu_chr_fe_disconnect:
 145  *
 146  * Close a fd accpeted by character backend.
 147  * Without associated Chardev, do nothing.
 148  */
 149 void qemu_chr_fe_disconnect(CharBackend *be);
 150
 151 /**
 152  * @qemu_chr_cleanup:
 153  *
 154  * Delete all chardevs (when leaving qemu)
 155  */
 156 void qemu_chr_cleanup(void);
 157
 158 /**
 159  * @qemu_chr_fe_wait_connected:
 160  *
 161  * Wait for characted backend to be connected, return < 0 on error or
 162  * if no assicated Chardev.
 163  */
 164 int qemu_chr_fe_wait_connected(CharBackend *be, Error **errp);
 165
 166 /**
 167  * @qemu_chr_new_noreplay:
 168  *
 169  * Create a new character backend from a URI.
 170  * Character device communications are not written
 171  * into the replay log.
 172  *
 173  * @label the name of the backend
 174  * @filename the URI
 175  *
 176  * Returns: a new character backend
 177  */
 178 Chardev *qemu_chr_new_noreplay(const char *label, const char *filename);
 179
 180 /**
 181  * @qemu_chr_fe_set_echo:
 182  *
 183  * Ask the backend to override its normal echo setting.  This only really
 184  * applies to the stdio backend and is used by the QMP server such that you
 185  * can see what you type if you try to type QMP commands.
 186  * Without associated Chardev, do nothing.
 187  *
 188  * @echo true to enable echo, false to disable echo
 189  */
 190 void qemu_chr_fe_set_echo(CharBackend *be, bool echo);
 191
 192 /**
 193  * @qemu_chr_fe_set_open:
 194  *
 195  * Set character frontend open status.  This is an indication that the
 196  * front end is ready (or not) to begin doing I/O.
 197  * Without associated Chardev, do nothing.
 198  */
 199 void qemu_chr_fe_set_open(CharBackend *be, int fe_open);
 200
 201 /**
 202  * @qemu_chr_fe_printf:
 203  *
 204  * Write to a character backend using a printf style interface.  This
 205  * function is thread-safe. It does nothing without associated
 206  * Chardev.
 207  *
 208  * @fmt see #printf
 209  */
 210 void qemu_chr_fe_printf(CharBackend *be, const char *fmt, ...)
 211     GCC_FMT_ATTR(2, 3);
 212
 213 /**
 214  * @qemu_chr_fe_add_watch:
 215  *
 216  * If the backend is connected, create and add a #GSource that fires
 217  * when the given condition (typically G_IO_OUT|G_IO_HUP or G_IO_HUP)
 218  * is active; return the #GSource's tag.  If it is disconnected,
 219  * or without associated Chardev, return 0.
 220  *
 221  * @cond the condition to poll for
 222  * @func the function to call when the condition happens
 223  * @user_data the opaque pointer to pass to @func
 224  *
 225  * Returns: the source tag
 226  */
 227 guint qemu_chr_fe_add_watch(CharBackend *be, GIOCondition cond,
 228                             GIOFunc func, void *user_data);
 229
 230 /**
 231  * @qemu_chr_fe_write:
 232  *
 233  * Write data to a character backend from the front end.  This function
 234  * will send data from the front end to the back end.  This function
 235  * is thread-safe.
 236  *
 237  * @buf the data
 238  * @len the number of bytes to send
 239  *
 240  * Returns: the number of bytes consumed (0 if no assicated Chardev)
 241  */
 242 int qemu_chr_fe_write(CharBackend *be, const uint8_t *buf, int len);
 243
 244 /**
 245  * @qemu_chr_fe_write_all:
 246  *
 247  * Write data to a character backend from the front end.  This function will
 248  * send data from the front end to the back end.  Unlike @qemu_chr_fe_write,
 249  * this function will block if the back end cannot consume all of the data
 250  * attempted to be written.  This function is thread-safe.
 251  *
 252  * @buf the data
 253  * @len the number of bytes to send
 254  *
 255  * Returns: the number of bytes consumed (0 if no assicated Chardev)
 256  */
 257 int qemu_chr_fe_write_all(CharBackend *be, const uint8_t *buf, int len);
 258
 259 /**
 260  * @qemu_chr_fe_read_all:
 261  *
 262  * Read data to a buffer from the back end.
 263  *
 264  * @buf the data buffer
 265  * @len the number of bytes to read
 266  *
 267  * Returns: the number of bytes read (0 if no assicated Chardev)
 268  */
 269 int qemu_chr_fe_read_all(CharBackend *be, uint8_t *buf, int len);
 270
 271 /**
 272  * @qemu_chr_fe_ioctl:
 273  *
 274  * Issue a device specific ioctl to a backend.  This function is thread-safe.
 275  *
 276  * @cmd see CHR_IOCTL_*
 277  * @arg the data associated with @cmd
 278  *
 279  * Returns: if @cmd is not supported by the backend or there is no
 280  *          associated Chardev, -ENOTSUP, otherwise the return
 281  *          value depends on the semantics of @cmd
 282  */
 283 int qemu_chr_fe_ioctl(CharBackend *be, int cmd, void *arg);
 284
 285 /**
 286  * @qemu_chr_fe_get_msgfd:
 287  *
 288  * For backends capable of fd passing, return the latest file descriptor passed
 289  * by a client.
 290  *
 291  * Returns: -1 if fd passing isn't supported or there is no pending file
 292  *          descriptor.  If a file descriptor is returned, subsequent calls to
 293  *          this function will return -1 until a client sends a new file
 294  *          descriptor.
 295  */
 296 int qemu_chr_fe_get_msgfd(CharBackend *be);
 297
 298 /**
 299  * @qemu_chr_fe_get_msgfds:
 300  *
 301  * For backends capable of fd passing, return the number of file received
 302  * descriptors and fills the fds array up to num elements
 303  *
 304  * Returns: -1 if fd passing isn't supported or there are no pending file
 305  *          descriptors.  If file descriptors are returned, subsequent calls to
 306  *          this function will return -1 until a client sends a new set of file
 307  *          descriptors.
 308  */
 309 int qemu_chr_fe_get_msgfds(CharBackend *be, int *fds, int num);
 310
 311 /**
 312  * @qemu_chr_fe_set_msgfds:
 313  *
 314  * For backends capable of fd passing, set an array of fds to be passed with
 315  * the next send operation.
 316  * A subsequent call to this function before calling a write function will
 317  * result in overwriting the fd array with the new value without being send.
 318  * Upon writing the message the fd array is freed.
 319  *
 320  * Returns: -1 if fd passing isn't supported or no associated Chardev.
 321  */
 322 int qemu_chr_fe_set_msgfds(CharBackend *be, int *fds, int num);
 323
 324 /**
 325  * @qemu_chr_be_can_write:
 326  *
 327  * Determine how much data the front end can currently accept.  This function
 328  * returns the number of bytes the front end can accept.  If it returns 0, the
 329  * front end cannot receive data at the moment.  The function must be polled
 330  * to determine when data can be received.
 331  *
 332  * Returns: the number of bytes the front end can receive via @qemu_chr_be_write
 333  */
 334 int qemu_chr_be_can_write(Chardev *s);
 335
 336 /**
 337  * @qemu_chr_be_write:
 338  *
 339  * Write data from the back end to the front end.  Before issuing this call,
 340  * the caller should call @qemu_chr_be_can_write to determine how much data
 341  * the front end can currently accept.
 342  *
 343  * @buf a buffer to receive data from the front end
 344  * @len the number of bytes to receive from the front end
 345  */
 346 void qemu_chr_be_write(Chardev *s, uint8_t *buf, int len);
 347
 348 /**
 349  * @qemu_chr_be_write_impl:
 350  *
 351  * Implementation of back end writing. Used by replay module.
 352  *
 353  * @buf a buffer to receive data from the front end
 354  * @len the number of bytes to receive from the front end
 355  */
 356 void qemu_chr_be_write_impl(Chardev *s, uint8_t *buf, int len);
 357
 358 /**
 359  * @qemu_chr_be_event:
 360  *
 361  * Send an event from the back end to the front end.
 362  *
 363  * @event the event to send
 364  */
 365 void qemu_chr_be_event(Chardev *s, int event);
 366
 367 /**
 368  * @qemu_chr_fe_init:
 369  *
 370  * Initializes a front end for the given CharBackend and
 371  * Chardev. Call qemu_chr_fe_deinit() to remove the association and
 372  * release the driver.
 373  *
 374  * Returns: false on error.
 375  */
 376 bool qemu_chr_fe_init(CharBackend *b, Chardev *s, Error **errp);
 377
 378 /**
 379  * @qemu_chr_fe_get_driver:
 380  *
 381  * Returns the driver associated with a CharBackend or NULL if no
 382  * associated Chardev.
 383  */
 384 Chardev *qemu_chr_fe_get_driver(CharBackend *be);
 385
 386 /**
 387  * @qemu_chr_fe_deinit:
 388  *
 389  * Dissociate the CharBackend from the Chardev.
 390  *
 391  * Safe to call without associated Chardev.
 392  */
 393 void qemu_chr_fe_deinit(CharBackend *b);
 394
 395 /**
 396  * @qemu_chr_fe_set_handlers:
 397  * @b: a CharBackend
 398  * @fd_can_read: callback to get the amount of data the frontend may
 399  *               receive
 400  * @fd_read: callback to receive data from char
 401  * @fd_event: event callback
 402  * @opaque: an opaque pointer for the callbacks
 403  * @context: a main loop context or NULL for the default
 404  * @set_open: whether to call qemu_chr_fe_set_open() implicitely when
 405  * any of the handler is non-NULL
 406  *
 407  * Set the front end char handlers. The front end takes the focus if
 408  * any of the handler is non-NULL.
 409  *
 410  * Without associated Chardev, nothing is changed.
 411  */
 412 void qemu_chr_fe_set_handlers(CharBackend *b,
 413                               IOCanReadHandler *fd_can_read,
 414                               IOReadHandler *fd_read,
 415                               IOEventHandler *fd_event,
 416                               void *opaque,
 417                               GMainContext *context,
 418                               bool set_open);
 419
 420 /**
 421  * @qemu_chr_fe_take_focus:
 422  *
 423  * Take the focus (if the front end is muxed).
 424  *
 425  * Without associated Chardev, nothing is changed.
 426  */
 427 void qemu_chr_fe_take_focus(CharBackend *b);
 428
 429 void qemu_chr_fe_accept_input(CharBackend *be);
 430 int qemu_chr_add_client(Chardev *s, int fd);
 431 Chardev *qemu_chr_find(const char *name);
 432
 433 bool qemu_chr_has_feature(Chardev *chr,
 434                           ChardevFeature feature);
 435 void qemu_chr_set_feature(Chardev *chr,
 436                           ChardevFeature feature);
 437 QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename);
 438 int qemu_chr_write_all(Chardev *s, const uint8_t *buf, int len);
 439 int qemu_chr_wait_connected(Chardev *chr, Error **errp);
 440
 441 #define TYPE_CHARDEV "chardev"
 442 #define CHARDEV(obj) OBJECT_CHECK(Chardev, (obj), TYPE_CHARDEV)
 443 #define CHARDEV_CLASS(klass) \
 444     OBJECT_CLASS_CHECK(ChardevClass, (klass), TYPE_CHARDEV)
 445 #define CHARDEV_GET_CLASS(obj) \
 446     OBJECT_GET_CLASS(ChardevClass, (obj), TYPE_CHARDEV)
 447
 448 #define TYPE_CHARDEV_NULL "chardev-null"
 449 #define TYPE_CHARDEV_MUX "chardev-mux"
 450 #define TYPE_CHARDEV_RINGBUF "chardev-ringbuf"
 451 #define TYPE_CHARDEV_PTY "chardev-pty"
 452 #define TYPE_CHARDEV_CONSOLE "chardev-console"
 453 #define TYPE_CHARDEV_STDIO "chardev-stdio"
 454 #define TYPE_CHARDEV_PIPE "chardev-pipe"
 455 #define TYPE_CHARDEV_MEMORY "chardev-memory"
 456 #define TYPE_CHARDEV_PARALLEL "chardev-parallel"
 457 #define TYPE_CHARDEV_FILE "chardev-file"
 458 #define TYPE_CHARDEV_SERIAL "chardev-serial"
 459 #define TYPE_CHARDEV_SOCKET "chardev-socket"
 460 #define TYPE_CHARDEV_UDP "chardev-udp"
 461
 462 #define CHARDEV_IS_RINGBUF(chr) \
 463     object_dynamic_cast(OBJECT(chr), TYPE_CHARDEV_RINGBUF)
 464 #define CHARDEV_IS_PTY(chr) \
 465     object_dynamic_cast(OBJECT(chr), TYPE_CHARDEV_PTY)
 466
 467 typedef struct ChardevClass {
 468     ObjectClass parent_class;
 469
 470     bool internal; /* TODO: eventually use TYPE_USER_CREATABLE */
 471     void (*parse)(QemuOpts *opts, ChardevBackend *backend, Error **errp);
 472
 473     void (*open)(Chardev *chr, ChardevBackend *backend,
 474                  bool *be_opened, Error **errp);
 475
 476     int (*chr_write)(Chardev *s, const uint8_t *buf, int len);
 477     int (*chr_sync_read)(Chardev *s, const uint8_t *buf, int len);
 478     GSource *(*chr_add_watch)(Chardev *s, GIOCondition cond);
 479     void (*chr_update_read_handler)(Chardev *s, GMainContext *context);
 480     int (*chr_ioctl)(Chardev *s, int cmd, void *arg);
 481     int (*get_msgfds)(Chardev *s, int* fds, int num);
 482     int (*set_msgfds)(Chardev *s, int *fds, int num);
 483     int (*chr_add_client)(Chardev *chr, int fd);
 484     int (*chr_wait_connected)(Chardev *chr, Error **errp);
 485     void (*chr_disconnect)(Chardev *chr);
 486     void (*chr_accept_input)(Chardev *chr);
 487     void (*chr_set_echo)(Chardev *chr, bool echo);
 488     void (*chr_set_fe_open)(Chardev *chr, int fe_open);
 489 } ChardevClass;
 490
 491 Chardev *qemu_chardev_new(const char *id, const char *typename,
 492                           ChardevBackend *backend, Error **errp);
 493
 494 extern int term_escape_char;
 495
 496 /* console.c */
 497 void qemu_chr_parse_vc(QemuOpts *opts, ChardevBackend *backend, Error **errp);
 498
 499 #endif