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