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 /* character device */
  11
  12 typedef enum {
  13     CHR_EVENT_BREAK, /* serial break char */
  14     CHR_EVENT_OPENED, /* new connection established */
  15     CHR_EVENT_MUX_IN, /* mux-focus was set to this terminal */
  16     CHR_EVENT_MUX_OUT, /* mux-focus will move on */
  17     CHR_EVENT_CLOSED /* connection closed */
  18 } QEMUChrEvent;
  19
  20 #define CHR_READ_BUF_LEN 4096
  21
  22 #define CHR_IOCTL_SERIAL_SET_PARAMS   1
  23 typedef struct {
  24     int speed;
  25     int parity;
  26     int data_bits;
  27     int stop_bits;
  28 } QEMUSerialSetParams;
  29
  30 #define CHR_IOCTL_SERIAL_SET_BREAK    2
  31
  32 #define CHR_IOCTL_PP_READ_DATA        3
  33 #define CHR_IOCTL_PP_WRITE_DATA       4
  34 #define CHR_IOCTL_PP_READ_CONTROL     5
  35 #define CHR_IOCTL_PP_WRITE_CONTROL    6
  36 #define CHR_IOCTL_PP_READ_STATUS      7
  37 #define CHR_IOCTL_PP_EPP_READ_ADDR    8
  38 #define CHR_IOCTL_PP_EPP_READ         9
  39 #define CHR_IOCTL_PP_EPP_WRITE_ADDR  10
  40 #define CHR_IOCTL_PP_EPP_WRITE       11
  41 #define CHR_IOCTL_PP_DATA_DIR        12
  42
  43 struct ParallelIOArg {
  44     void *buffer;
  45     int count;
  46 };
  47
  48 #define CHR_IOCTL_SERIAL_SET_TIOCM   13
  49 #define CHR_IOCTL_SERIAL_GET_TIOCM   14
  50
  51 #define CHR_TIOCM_CTS   0x020
  52 #define CHR_TIOCM_CAR   0x040
  53 #define CHR_TIOCM_DSR   0x100
  54 #define CHR_TIOCM_RI    0x080
  55 #define CHR_TIOCM_DTR   0x002
  56 #define CHR_TIOCM_RTS   0x004
  57
  58 typedef void IOEventHandler(void *opaque, int event);
  59
  60 typedef enum {
  61     /* Whether the chardev peer is able to close and
  62      * reopen the data channel, thus requiring support
  63      * for qemu_chr_wait_connected() to wait for a
  64      * valid connection */
  65     QEMU_CHAR_FEATURE_RECONNECTABLE,
  66     /* Whether it is possible to send/recv file descriptors
  67      * over the data channel */
  68     QEMU_CHAR_FEATURE_FD_PASS,
  69     /* Whether replay or record mode is enabled */
  70     QEMU_CHAR_FEATURE_REPLAY,
  71
  72     QEMU_CHAR_FEATURE_LAST,
  73 } ChardevFeature;
  74
  75 /* This is the backend as seen by frontend, the actual backend is
  76  * Chardev */
  77 typedef struct CharBackend {
  78     Chardev *chr;
  79     IOEventHandler *chr_event;
  80     IOCanReadHandler *chr_can_read;
  81     IOReadHandler *chr_read;
  82     void *opaque;
  83     int tag;
  84     int fe_open;
  85 } CharBackend;
  86
  87 struct Chardev {
  88     Object parent_obj;
  89
  90     QemuMutex chr_write_lock;
  91     CharBackend *be;
  92     char *label;
  93     char *filename;
  94     int logfd;
  95     int be_open;
  96     guint fd_in_tag;
  97     DECLARE_BITMAP(features, QEMU_CHAR_FEATURE_LAST);
  98     QTAILQ_ENTRY(Chardev) next;
  99 };
 100
 101 /**
 102  * @qemu_chr_new_from_opts:
 103  *
 104  * Create a new character backend from a QemuOpts list.
 105  *
 106  * @opts see qemu-config.c for a list of valid options
 107  *
 108  * Returns: a new character backend
 109  */
 110 Chardev *qemu_chr_new_from_opts(QemuOpts *opts,
 111                                 Error **errp);
 112
 113 /**
 114  * @qemu_chr_parse_common:
 115  *
 116  * Parse the common options available to all character backends.
 117  *
 118  * @opts the options that still need parsing
 119  * @backend a new backend
 120  */
 121 void qemu_chr_parse_common(QemuOpts *opts, ChardevCommon *backend);
 122
 123 /**
 124  * @qemu_chr_new:
 125  *
 126  * Create a new character backend from a URI.
 127  *
 128  * @label the name of the backend
 129  * @filename the URI
 130  *
 131  * Returns: a new character backend
 132  */
 133 Chardev *qemu_chr_new(const char *label, const char *filename);
 134
 135
 136 /**
 137  * @qemu_chr_fe_disconnect:
 138  *
 139  * Close a fd accpeted by character backend.
 140  * Without associated Chardev, do nothing.
 141  */
 142 void qemu_chr_fe_disconnect(CharBackend *be);
 143
 144 /**
 145  * @qemu_chr_cleanup:
 146  *
 147  * Delete all chardevs (when leaving qemu)
 148  */
 149 void qemu_chr_cleanup(void);
 150
 151 /**
 152  * @qemu_chr_fe_wait_connected:
 153  *
 154  * Wait for characted backend to be connected, return < 0 on error or
 155  * if no assicated Chardev.
 156  */
 157 int qemu_chr_fe_wait_connected(CharBackend *be, Error **errp);
 158
 159 /**
 160  * @qemu_chr_new_noreplay:
 161  *
 162  * Create a new character backend from a URI.
 163  * Character device communications are not written
 164  * into the replay log.
 165  *
 166  * @label the name of the backend
 167  * @filename the URI
 168  *
 169  * Returns: a new character backend
 170  */
 171 Chardev *qemu_chr_new_noreplay(const char *label, const char *filename);
 172
 173 /**
 174  * @qemu_chr_delete:
 175  *
 176  * Destroy a character backend and remove it from the list of
 177  * identified character backends.
 178  */
 179 void qemu_chr_delete(Chardev *chr);
 180
 181 /**
 182  * @qemu_chr_fe_set_echo:
 183  *
 184  * Ask the backend to override its normal echo setting.  This only really
 185  * applies to the stdio backend and is used by the QMP server such that you
 186  * can see what you type if you try to type QMP commands.
 187  * Without associated Chardev, do nothing.
 188  *
 189  * @echo true to enable echo, false to disable echo
 190  */
 191 void qemu_chr_fe_set_echo(CharBackend *be, bool echo);
 192
 193 /**
 194  * @qemu_chr_fe_set_open:
 195  *
 196  * Set character frontend open status.  This is an indication that the
 197  * front end is ready (or not) to begin doing I/O.
 198  * Without associated Chardev, do nothing.
 199  */
 200 void qemu_chr_fe_set_open(CharBackend *be, int fe_open);
 201
 202 /**
 203  * @qemu_chr_fe_printf:
 204  *
 205  * Write to a character backend using a printf style interface.  This
 206  * function is thread-safe. It does nothing without associated
 207  * Chardev.
 208  *
 209  * @fmt see #printf
 210  */
 211 void qemu_chr_fe_printf(CharBackend *be, const char *fmt, ...)
 212     GCC_FMT_ATTR(2, 3);
 213
 214 /**
 215  * @qemu_chr_fe_add_watch:
 216  *
 217  * If the backend is connected, create and add a #GSource that fires
 218  * when the given condition (typically G_IO_OUT|G_IO_HUP or G_IO_HUP)
 219  * is active; return the #GSource's tag.  If it is disconnected,
 220  * or without associated Chardev, return 0.
 221  *
 222  * @cond the condition to poll for
 223  * @func the function to call when the condition happens
 224  * @user_data the opaque pointer to pass to @func
 225  *
 226  * Returns: the source tag
 227  */
 228 guint qemu_chr_fe_add_watch(CharBackend *be, GIOCondition cond,
 229                             GIOFunc func, void *user_data);
 230
 231 /**
 232  * @qemu_chr_fe_write:
 233  *
 234  * Write data to a character backend from the front end.  This function
 235  * will send data from the front end to the back end.  This function
 236  * is thread-safe.
 237  *
 238  * @buf the data
 239  * @len the number of bytes to send
 240  *
 241  * Returns: the number of bytes consumed (0 if no assicated Chardev)
 242  */
 243 int qemu_chr_fe_write(CharBackend *be, const uint8_t *buf, int len);
 244
 245 /**
 246  * @qemu_chr_fe_write_all:
 247  *
 248  * Write data to a character backend from the front end.  This function will
 249  * send data from the front end to the back end.  Unlike @qemu_chr_fe_write,
 250  * this function will block if the back end cannot consume all of the data
 251  * attempted to be written.  This function is thread-safe.
 252  *
 253  * @buf the data
 254  * @len the number of bytes to send
 255  *
 256  * Returns: the number of bytes consumed (0 if no assicated Chardev)
 257  */
 258 int qemu_chr_fe_write_all(CharBackend *be, const uint8_t *buf, int len);
 259
 260 /**
 261  * @qemu_chr_fe_read_all:
 262  *
 263  * Read data to a buffer from the back end.
 264  *
 265  * @buf the data buffer
 266  * @len the number of bytes to read
 267  *
 268  * Returns: the number of bytes read (0 if no assicated Chardev)
 269  */
 270 int qemu_chr_fe_read_all(CharBackend *be, uint8_t *buf, int len);
 271
 272 /**
 273  * @qemu_chr_fe_ioctl:
 274  *
 275  * Issue a device specific ioctl to a backend.  This function is thread-safe.
 276  *
 277  * @cmd see CHR_IOCTL_*
 278  * @arg the data associated with @cmd
 279  *
 280  * Returns: if @cmd is not supported by the backend or there is no
 281  *          associated Chardev, -ENOTSUP, otherwise the return
 282  *          value depends on the semantics of @cmd
 283  */
 284 int qemu_chr_fe_ioctl(CharBackend *be, int cmd, void *arg);
 285
 286 /**
 287  * @qemu_chr_fe_get_msgfd:
 288  *
 289  * For backends capable of fd passing, return the latest file descriptor passed
 290  * by a client.
 291  *
 292  * Returns: -1 if fd passing isn't supported or there is no pending file
 293  *          descriptor.  If a file descriptor is returned, subsequent calls to
 294  *          this function will return -1 until a client sends a new file
 295  *          descriptor.
 296  */
 297 int qemu_chr_fe_get_msgfd(CharBackend *be);
 298
 299 /**
 300  * @qemu_chr_fe_get_msgfds:
 301  *
 302  * For backends capable of fd passing, return the number of file received
 303  * descriptors and fills the fds array up to num elements
 304  *
 305  * Returns: -1 if fd passing isn't supported or there are no pending file
 306  *          descriptors.  If file descriptors are returned, subsequent calls to
 307  *          this function will return -1 until a client sends a new set of file
 308  *          descriptors.
 309  */
 310 int qemu_chr_fe_get_msgfds(CharBackend *be, int *fds, int num);
 311
 312 /**
 313  * @qemu_chr_fe_set_msgfds:
 314  *
 315  * For backends capable of fd passing, set an array of fds to be passed with
 316  * the next send operation.
 317  * A subsequent call to this function before calling a write function will
 318  * result in overwriting the fd array with the new value without being send.
 319  * Upon writing the message the fd array is freed.
 320  *
 321  * Returns: -1 if fd passing isn't supported or no associated Chardev.
 322  */
 323 int qemu_chr_fe_set_msgfds(CharBackend *be, int *fds, int num);
 324
 325 /**
 326  * @qemu_chr_be_can_write:
 327  *
 328  * Determine how much data the front end can currently accept.  This function
 329  * returns the number of bytes the front end can accept.  If it returns 0, the
 330  * front end cannot receive data at the moment.  The function must be polled
 331  * to determine when data can be received.
 332  *
 333  * Returns: the number of bytes the front end can receive via @qemu_chr_be_write
 334  */
 335 int qemu_chr_be_can_write(Chardev *s);
 336
 337 /**
 338  * @qemu_chr_be_write:
 339  *
 340  * Write data from the back end to the front end.  Before issuing this call,
 341  * the caller should call @qemu_chr_be_can_write to determine how much data
 342  * the front end can currently accept.
 343  *
 344  * @buf a buffer to receive data from the front end
 345  * @len the number of bytes to receive from the front end
 346  */
 347 void qemu_chr_be_write(Chardev *s, uint8_t *buf, int len);
 348
 349 /**
 350  * @qemu_chr_be_write_impl:
 351  *
 352  * Implementation of back end writing. Used by replay module.
 353  *
 354  * @buf a buffer to receive data from the front end
 355  * @len the number of bytes to receive from the front end
 356  */
 357 void qemu_chr_be_write_impl(Chardev *s, uint8_t *buf, int len);
 358
 359 /**
 360  * @qemu_chr_be_event:
 361  *
 362  * Send an event from the back end to the front end.
 363  *
 364  * @event the event to send
 365  */
 366 void qemu_chr_be_event(Chardev *s, int event);
 367
 368 /**
 369  * @qemu_chr_fe_init:
 370  *
 371  * Initializes a front end for the given CharBackend and
 372  * Chardev. Call qemu_chr_fe_deinit() to remove the association and
 373  * release the driver.
 374  *
 375  * Returns: false on error.
 376  */
 377 bool qemu_chr_fe_init(CharBackend *b, Chardev *s, Error **errp);
 378
 379 /**
 380  * @qemu_chr_fe_get_driver:
 381  *
 382  * Returns the driver associated with a CharBackend or NULL if no
 383  * associated Chardev.
 384  */
 385 Chardev *qemu_chr_fe_get_driver(CharBackend *be);
 386
 387 /**
 388  * @qemu_chr_fe_deinit:
 389  *
 390  * Dissociate the CharBackend from the Chardev.
 391  *
 392  * Safe to call without associated Chardev.
 393  */
 394 void qemu_chr_fe_deinit(CharBackend *b);
 395
 396 /**
 397  * @qemu_chr_fe_set_handlers:
 398  * @b: a CharBackend
 399  * @fd_can_read: callback to get the amount of data the frontend may
 400  *               receive
 401  * @fd_read: callback to receive data from char
 402  * @fd_event: event callback
 403  * @opaque: an opaque pointer for the callbacks
 404  * @context: a main loop context or NULL for the default
 405  * @set_open: whether to call qemu_chr_fe_set_open() implicitely when
 406  * any of the handler is non-NULL
 407  *
 408  * Set the front end char handlers. The front end takes the focus if
 409  * any of the handler is non-NULL.
 410  *
 411  * Without associated Chardev, nothing is changed.
 412  */
 413 void qemu_chr_fe_set_handlers(CharBackend *b,
 414                               IOCanReadHandler *fd_can_read,
 415                               IOReadHandler *fd_read,
 416                               IOEventHandler *fd_event,
 417                               void *opaque,
 418                               GMainContext *context,
 419                               bool set_open);
 420
 421 /**
 422  * @qemu_chr_fe_take_focus:
 423  *
 424  * Take the focus (if the front end is muxed).
 425  *
 426  * Without associated Chardev, nothing is changed.
 427  */
 428 void qemu_chr_fe_take_focus(CharBackend *b);
 429
 430 void qemu_chr_be_generic_open(Chardev *s);
 431 void qemu_chr_fe_accept_input(CharBackend *be);
 432 int qemu_chr_add_client(Chardev *s, int fd);
 433 Chardev *qemu_chr_find(const char *name);
 434
 435 bool qemu_chr_has_feature(Chardev *chr,
 436                           ChardevFeature feature);
 437 void qemu_chr_set_feature(Chardev *chr,
 438                           ChardevFeature feature);
 439 QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename);
 440 int qemu_chr_write_all(Chardev *s, const uint8_t *buf, int len);
 441 int qemu_chr_wait_connected(Chardev *chr, Error **errp);
 442
 443 #define TYPE_CHARDEV "chardev"
 444 #define CHARDEV(obj) OBJECT_CHECK(Chardev, (obj), TYPE_CHARDEV)
 445 #define CHARDEV_CLASS(klass) \
 446     OBJECT_CLASS_CHECK(ChardevClass, (klass), TYPE_CHARDEV)
 447 #define CHARDEV_GET_CLASS(obj) \
 448     OBJECT_GET_CLASS(ChardevClass, (obj), TYPE_CHARDEV)
 449
 450 #define TYPE_CHARDEV_NULL "chardev-null"
 451 #define TYPE_CHARDEV_MUX "chardev-mux"
 452 #define TYPE_CHARDEV_RINGBUF "chardev-ringbuf"
 453 #define TYPE_CHARDEV_PTY "chardev-pty"
 454 #define TYPE_CHARDEV_CONSOLE "chardev-console"
 455 #define TYPE_CHARDEV_STDIO "chardev-stdio"
 456 #define TYPE_CHARDEV_PIPE "chardev-pipe"
 457 #define TYPE_CHARDEV_MEMORY "chardev-memory"
 458 #define TYPE_CHARDEV_PARALLEL "chardev-parallel"
 459 #define TYPE_CHARDEV_FILE "chardev-file"
 460 #define TYPE_CHARDEV_SERIAL "chardev-serial"
 461 #define TYPE_CHARDEV_SOCKET "chardev-socket"
 462 #define TYPE_CHARDEV_UDP "chardev-udp"
 463
 464 #define CHARDEV_IS_RINGBUF(chr) \
 465     object_dynamic_cast(OBJECT(chr), TYPE_CHARDEV_RINGBUF)
 466 #define CHARDEV_IS_PTY(chr) \
 467     object_dynamic_cast(OBJECT(chr), TYPE_CHARDEV_PTY)
 468
 469 typedef struct ChardevClass {
 470     ObjectClass parent_class;
 471
 472     bool internal; /* TODO: eventually use TYPE_USER_CREATABLE */
 473     void (*parse)(QemuOpts *opts, ChardevBackend *backend, Error **errp);
 474
 475     void (*open)(Chardev *chr, ChardevBackend *backend,
 476                  bool *be_opened, Error **errp);
 477
 478     int (*chr_write)(Chardev *s, const uint8_t *buf, int len);
 479     int (*chr_sync_read)(Chardev *s, const uint8_t *buf, int len);
 480     GSource *(*chr_add_watch)(Chardev *s, GIOCondition cond);
 481     void (*chr_update_read_handler)(Chardev *s, GMainContext *context);
 482     int (*chr_ioctl)(Chardev *s, int cmd, void *arg);
 483     int (*get_msgfds)(Chardev *s, int* fds, int num);
 484     int (*set_msgfds)(Chardev *s, int *fds, int num);
 485     int (*chr_add_client)(Chardev *chr, int fd);
 486     int (*chr_wait_connected)(Chardev *chr, Error **errp);
 487     void (*chr_disconnect)(Chardev *chr);
 488     void (*chr_accept_input)(Chardev *chr);
 489     void (*chr_set_echo)(Chardev *chr, bool echo);
 490     void (*chr_set_fe_open)(Chardev *chr, int fe_open);
 491 } ChardevClass;
 492
 493 Chardev *qemu_chardev_new(const char *id, const char *typename,
 494                           ChardevBackend *backend, Error **errp);
 495
 496 extern int term_escape_char;
 497
 498 /* console.c */
 499 void qemu_chr_parse_vc(QemuOpts *opts, ChardevBackend *backend, Error **errp);
 500
 501 #endif