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     int tag;
  80 } CharBackend;
  81
  82 struct CharDriverState {
  83     QemuMutex chr_write_lock;
  84     int (*chr_write)(struct CharDriverState *s, const uint8_t *buf, int len);
  85     int (*chr_sync_read)(struct CharDriverState *s,
  86                          const uint8_t *buf, int len);
  87     GSource *(*chr_add_watch)(struct CharDriverState *s, GIOCondition cond);
  88     void (*chr_update_read_handler)(struct CharDriverState *s,
  89                                     GMainContext *context, int tag);
  90     int (*chr_ioctl)(struct CharDriverState *s, int cmd, void *arg);
  91     int (*get_msgfds)(struct CharDriverState *s, int* fds, int num);
  92     int (*set_msgfds)(struct CharDriverState *s, int *fds, int num);
  93     int (*chr_add_client)(struct CharDriverState *chr, int fd);
  94     int (*chr_wait_connected)(struct CharDriverState *chr, Error **errp);
  95     IOEventHandler *chr_event;
  96     IOCanReadHandler *chr_can_read;
  97     IOReadHandler *chr_read;
  98     void *handler_opaque;
  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     void *opaque;
 106     char *label;
 107     char *filename;
 108     int logfd;
 109     int be_open;
 110     int fe_open;
 111     int explicit_fe_open;
 112     int explicit_be_open;
 113     int avail_connections;
 114     int is_mux;
 115     guint fd_in_tag;
 116     bool replay;
 117     DECLARE_BITMAP(features, QEMU_CHAR_FEATURE_LAST);
 118     QTAILQ_ENTRY(CharDriverState) next;
 119 };
 120
 121 /**
 122  * qemu_chr_alloc:
 123  * @backend: the common backend config
 124  * @errp: pointer to a NULL-initialized error object
 125  *
 126  * Allocate and initialize a new CharDriverState.
 127  *
 128  * Returns: a newly allocated CharDriverState, or NULL on error.
 129  */
 130 CharDriverState *qemu_chr_alloc(ChardevCommon *backend, Error **errp);
 131
 132 /**
 133  * @qemu_chr_new_from_opts:
 134  *
 135  * Create a new character backend from a QemuOpts list.
 136  *
 137  * @opts see qemu-config.c for a list of valid options
 138  *
 139  * Returns: a new character backend
 140  */
 141 CharDriverState *qemu_chr_new_from_opts(QemuOpts *opts,
 142                                         Error **errp);
 143
 144 /**
 145  * @qemu_chr_parse_common:
 146  *
 147  * Parse the common options available to all character backends.
 148  *
 149  * @opts the options that still need parsing
 150  * @backend a new backend
 151  */
 152 void qemu_chr_parse_common(QemuOpts *opts, ChardevCommon *backend);
 153
 154 /**
 155  * @qemu_chr_new:
 156  *
 157  * Create a new character backend from a URI.
 158  *
 159  * @label the name of the backend
 160  * @filename the URI
 161  *
 162  * Returns: a new character backend
 163  */
 164 CharDriverState *qemu_chr_new(const char *label, const char *filename);
 165
 166
 167 /**
 168  * @qemu_chr_fe_disconnect:
 169  *
 170  * Close a fd accpeted by character backend.
 171  */
 172 void qemu_chr_fe_disconnect(CharBackend *be);
 173
 174 /**
 175  * @qemu_chr_cleanup:
 176  *
 177  * Delete all chardevs (when leaving qemu)
 178  */
 179 void qemu_chr_cleanup(void);
 180
 181 /**
 182  * @qemu_chr_fe_wait_connected:
 183  *
 184  * Wait for characted backend to be connected.
 185  */
 186 int qemu_chr_fe_wait_connected(CharBackend *be, Error **errp);
 187
 188 /**
 189  * @qemu_chr_new_noreplay:
 190  *
 191  * Create a new character backend from a URI.
 192  * Character device communications are not written
 193  * into the replay log.
 194  *
 195  * @label the name of the backend
 196  * @filename the URI
 197  *
 198  * Returns: a new character backend
 199  */
 200 CharDriverState *qemu_chr_new_noreplay(const char *label, const char *filename);
 201
 202 /**
 203  * @qemu_chr_delete:
 204  *
 205  * Destroy a character backend and remove it from the list of
 206  * identified character backends.
 207  */
 208 void qemu_chr_delete(CharDriverState *chr);
 209
 210 /**
 211  * @qemu_chr_free:
 212  *
 213  * Destroy a character backend.
 214  */
 215 void qemu_chr_free(CharDriverState *chr);
 216
 217 /**
 218  * @qemu_chr_fe_set_echo:
 219  *
 220  * Ask the backend to override its normal echo setting.  This only really
 221  * applies to the stdio backend and is used by the QMP server such that you
 222  * can see what you type if you try to type QMP commands.
 223  *
 224  * @echo true to enable echo, false to disable echo
 225  */
 226 void qemu_chr_fe_set_echo(CharBackend *be, bool echo);
 227
 228 /**
 229  * @qemu_chr_fe_set_open:
 230  *
 231  * Set character frontend open status.  This is an indication that the
 232  * front end is ready (or not) to begin doing I/O.
 233  */
 234 void qemu_chr_fe_set_open(CharBackend *be, int fe_open);
 235
 236 /**
 237  * @qemu_chr_fe_event:
 238  *
 239  * Send an event from the front end to the back end.
 240  *
 241  * @event the event to send
 242  */
 243 void qemu_chr_fe_event(CharBackend *be, int event);
 244
 245 /**
 246  * @qemu_chr_fe_printf:
 247  *
 248  * Write to a character backend using a printf style interface.
 249  * This function is thread-safe.
 250  *
 251  * @fmt see #printf
 252  */
 253 void qemu_chr_fe_printf(CharBackend *be, const char *fmt, ...)
 254     GCC_FMT_ATTR(2, 3);
 255
 256 /**
 257  * @qemu_chr_fe_add_watch:
 258  *
 259  * If the backend is connected, create and add a #GSource that fires
 260  * when the given condition (typically G_IO_OUT|G_IO_HUP or G_IO_HUP)
 261  * is active; return the #GSource's tag.  If it is disconnected,
 262  * return 0.
 263  *
 264  * @cond the condition to poll for
 265  * @func the function to call when the condition happens
 266  * @user_data the opaque pointer to pass to @func
 267  */
 268 guint qemu_chr_fe_add_watch(CharBackend *be, GIOCondition cond,
 269                             GIOFunc func, void *user_data);
 270
 271 /**
 272  * @qemu_chr_fe_write:
 273  *
 274  * Write data to a character backend from the front end.  This function
 275  * will send data from the front end to the back end.  This function
 276  * is thread-safe.
 277  *
 278  * @buf the data
 279  * @len the number of bytes to send
 280  *
 281  * Returns: the number of bytes consumed
 282  */
 283 int qemu_chr_fe_write(CharBackend *be, const uint8_t *buf, int len);
 284
 285 /**
 286  * @qemu_chr_fe_write_all:
 287  *
 288  * Write data to a character backend from the front end.  This function will
 289  * send data from the front end to the back end.  Unlike @qemu_chr_fe_write,
 290  * this function will block if the back end cannot consume all of the data
 291  * attempted to be written.  This function is thread-safe.
 292  *
 293  * @buf the data
 294  * @len the number of bytes to send
 295  *
 296  * Returns: the number of bytes consumed
 297  */
 298 int qemu_chr_fe_write_all(CharBackend *be, const uint8_t *buf, int len);
 299
 300 /**
 301  * @qemu_chr_fe_read_all:
 302  *
 303  * Read data to a buffer from the back end.
 304  *
 305  * @buf the data buffer
 306  * @len the number of bytes to read
 307  *
 308  * Returns: the number of bytes read
 309  */
 310 int qemu_chr_fe_read_all(CharBackend *be, uint8_t *buf, int len);
 311
 312 /**
 313  * @qemu_chr_fe_ioctl:
 314  *
 315  * Issue a device specific ioctl to a backend.  This function is thread-safe.
 316  *
 317  * @cmd see CHR_IOCTL_*
 318  * @arg the data associated with @cmd
 319  *
 320  * Returns: if @cmd is not supported by the backend, -ENOTSUP, otherwise the
 321  *          return value depends on the semantics of @cmd
 322  */
 323 int qemu_chr_fe_ioctl(CharBackend *be, int cmd, void *arg);
 324
 325 /**
 326  * @qemu_chr_fe_get_msgfd:
 327  *
 328  * For backends capable of fd passing, return the latest file descriptor passed
 329  * by a client.
 330  *
 331  * Returns: -1 if fd passing isn't supported or there is no pending file
 332  *          descriptor.  If a file descriptor is returned, subsequent calls to
 333  *          this function will return -1 until a client sends a new file
 334  *          descriptor.
 335  */
 336 int qemu_chr_fe_get_msgfd(CharBackend *be);
 337
 338 /**
 339  * @qemu_chr_fe_get_msgfds:
 340  *
 341  * For backends capable of fd passing, return the number of file received
 342  * descriptors and fills the fds array up to num elements
 343  *
 344  * Returns: -1 if fd passing isn't supported or there are no pending file
 345  *          descriptors.  If file descriptors are returned, subsequent calls to
 346  *          this function will return -1 until a client sends a new set of file
 347  *          descriptors.
 348  */
 349 int qemu_chr_fe_get_msgfds(CharBackend *be, int *fds, int num);
 350
 351 /**
 352  * @qemu_chr_fe_set_msgfds:
 353  *
 354  * For backends capable of fd passing, set an array of fds to be passed with
 355  * the next send operation.
 356  * A subsequent call to this function before calling a write function will
 357  * result in overwriting the fd array with the new value without being send.
 358  * Upon writing the message the fd array is freed.
 359  *
 360  * Returns: -1 if fd passing isn't supported.
 361  */
 362 int qemu_chr_fe_set_msgfds(CharBackend *be, int *fds, int num);
 363
 364 /**
 365  * @qemu_chr_fe_claim:
 366  *
 367  * Claim a backend before using it, should be called before calling
 368  * qemu_chr_fe_set_handlers().
 369  *
 370  * Returns: -1 if the backend is already in use by another frontend, 0 on
 371  *          success.
 372  */
 373 int qemu_chr_fe_claim(CharDriverState *s);
 374
 375 /**
 376  * @qemu_chr_fe_claim_no_fail:
 377  *
 378  * Like qemu_chr_fe_claim, but will exit qemu with an error when the
 379  * backend is already in use.
 380  */
 381 void qemu_chr_fe_claim_no_fail(CharDriverState *s);
 382
 383 /**
 384  * @qemu_chr_fe_release:
 385  *
 386  * Release a backend for use by another frontend.
 387  *
 388  * Returns: -1 if the backend is already in use by another frontend, 0 on
 389  *          success.
 390  */
 391 void qemu_chr_fe_release(CharDriverState *s);
 392
 393 /**
 394  * @qemu_chr_be_can_write:
 395  *
 396  * Determine how much data the front end can currently accept.  This function
 397  * returns the number of bytes the front end can accept.  If it returns 0, the
 398  * front end cannot receive data at the moment.  The function must be polled
 399  * to determine when data can be received.
 400  *
 401  * Returns: the number of bytes the front end can receive via @qemu_chr_be_write
 402  */
 403 int qemu_chr_be_can_write(CharDriverState *s);
 404
 405 /**
 406  * @qemu_chr_be_write:
 407  *
 408  * Write data from the back end to the front end.  Before issuing this call,
 409  * the caller should call @qemu_chr_be_can_write to determine how much data
 410  * the front end can currently accept.
 411  *
 412  * @buf a buffer to receive data from the front end
 413  * @len the number of bytes to receive from the front end
 414  */
 415 void qemu_chr_be_write(CharDriverState *s, uint8_t *buf, int len);
 416
 417 /**
 418  * @qemu_chr_be_write_impl:
 419  *
 420  * Implementation of back end writing. Used by replay module.
 421  *
 422  * @buf a buffer to receive data from the front end
 423  * @len the number of bytes to receive from the front end
 424  */
 425 void qemu_chr_be_write_impl(CharDriverState *s, uint8_t *buf, int len);
 426
 427 /**
 428  * @qemu_chr_be_event:
 429  *
 430  * Send an event from the back end to the front end.
 431  *
 432  * @event the event to send
 433  */
 434 void qemu_chr_be_event(CharDriverState *s, int event);
 435
 436 /**
 437  * @qemu_chr_fe_init:
 438  *
 439  * Initializes a front end for the given CharBackend and
 440  * CharDriver.
 441  *
 442  * Returns: false on error.
 443  */
 444 bool qemu_chr_fe_init(CharBackend *b, CharDriverState *s, Error **errp);
 445
 446 /**
 447  * @qemu_chr_fe_get_driver:
 448  *
 449  * Returns the driver associated with a CharBackend or NULL.
 450  */
 451 CharDriverState *qemu_chr_fe_get_driver(CharBackend *be);
 452
 453 /**
 454  * @qemu_chr_fe_set_handlers:
 455  * @b: a CharBackend
 456  * @fd_can_read: callback to get the amount of data the frontend may
 457  *               receive
 458  * @fd_read: callback to receive data from char
 459  * @fd_event: event callback
 460  * @opaque: an opaque pointer for the callbacks
 461  * @context: a main loop context or NULL for the default
 462  *
 463  * Set the front end char handlers.
 464  */
 465 void qemu_chr_fe_set_handlers(CharBackend *b,
 466                               IOCanReadHandler *fd_can_read,
 467                               IOReadHandler *fd_read,
 468                               IOEventHandler *fd_event,
 469                               void *opaque,
 470                               GMainContext *context);
 471
 472 /**
 473  * @qemu_chr_fe_take_focus:
 474  *
 475  * Take the focus (if the front end is muxed)
 476  */
 477 void qemu_chr_fe_take_focus(CharBackend *b);
 478
 479 void qemu_chr_be_generic_open(CharDriverState *s);
 480 void qemu_chr_fe_accept_input(CharBackend *be);
 481 int qemu_chr_add_client(CharDriverState *s, int fd);
 482 CharDriverState *qemu_chr_find(const char *name);
 483 bool chr_is_ringbuf(const CharDriverState *chr);
 484
 485 bool qemu_chr_has_feature(CharDriverState *chr,
 486                           CharDriverFeature feature);
 487 void qemu_chr_set_feature(CharDriverState *chr,
 488                           CharDriverFeature feature);
 489 QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename);
 490
 491 void register_char_driver(const char *name, ChardevBackendKind kind,
 492         void (*parse)(QemuOpts *opts, ChardevBackend *backend, Error **errp),
 493         CharDriverState *(*create)(const char *id, ChardevBackend *backend,
 494                                    ChardevReturn *ret, Error **errp));
 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