include/chardev/char.h

   1 #ifndef QEMU_CHAR_H
   2 #define QEMU_CHAR_H
   3
   4 #include "qapi/qapi-types-char.h"
   5 #include "qemu/bitmap.h"
   6 #include "qemu/thread.h"
   7 #include "qom/object.h"
   8
   9 #define IAC_EOR 239
  10 #define IAC_SE 240
  11 #define IAC_NOP 241
  12 #define IAC_BREAK 243
  13 #define IAC_IP 244
  14 #define IAC_SB 250
  15 #define IAC 255
  16
  17 /* character device */
  18 typedef struct CharBackend CharBackend;
  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.  NOTE: currently this event
  26                       * is only bound to the read port of the chardev.
  27                       * Normally the read port and write port of a
  28                       * chardev should be the same, but it can be
  29                       * different, e.g., for fd chardevs, when the two
  30                       * fds are different.  So when we received the
  31                       * CLOSED event it's still possible that the out
  32                       * port is still open.  TODO: we should only send
  33                       * the CLOSED event when both ports are closed.
  34                       */
  35 } QEMUChrEvent;
  36
  37 #define CHR_READ_BUF_LEN 4096
  38
  39 typedef enum {
  40     /* Whether the chardev peer is able to close and
  41      * reopen the data channel, thus requiring support
  42      * for qemu_chr_wait_connected() to wait for a
  43      * valid connection */
  44     QEMU_CHAR_FEATURE_RECONNECTABLE,
  45     /* Whether it is possible to send/recv file descriptors
  46      * over the data channel */
  47     QEMU_CHAR_FEATURE_FD_PASS,
  48     /* Whether replay or record mode is enabled */
  49     QEMU_CHAR_FEATURE_REPLAY,
  50     /* Whether the gcontext can be changed after calling
  51      * qemu_chr_be_update_read_handlers() */
  52     QEMU_CHAR_FEATURE_GCONTEXT,
  53
  54     QEMU_CHAR_FEATURE_LAST,
  55 } ChardevFeature;
  56
  57 #define qemu_chr_replay(chr) qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_REPLAY)
  58
  59 struct Chardev {
  60     Object parent_obj;
  61
  62     QemuMutex chr_write_lock;
  63     CharBackend *be;
  64     char *label;
  65     char *filename;
  66     int logfd;
  67     int be_open;
  68     GSource *gsource;
  69     GMainContext *gcontext;
  70     DECLARE_BITMAP(features, QEMU_CHAR_FEATURE_LAST);
  71 };
  72
  73 /**
  74  * qemu_chr_new_from_opts:
  75  * @opts: see qemu-config.c for a list of valid options
  76  * @context: the #GMainContext to be used at initialization time
  77  *
  78  * Create a new character backend from a QemuOpts list.
  79  *
  80  * Returns: on success: a new character backend
  81  *          otherwise:  NULL; @errp specifies the error
  82  *                            or left untouched in case of help option
  83  */
  84 Chardev *qemu_chr_new_from_opts(QemuOpts *opts,
  85                                 GMainContext *context,
  86                                 Error **errp);
  87
  88 /**
  89  * qemu_chr_parse_common:
  90  * @opts: the options that still need parsing
  91  * @backend: a new backend
  92  *
  93  * Parse the common options available to all character backends.
  94  */
  95 void qemu_chr_parse_common(QemuOpts *opts, ChardevCommon *backend);
  96
  97 /**
  98  * qemu_chr_parse_opts:
  99  *
 100  * Parse the options to the ChardevBackend struct.
 101  *
 102  * Returns: a new backend or NULL on error
 103  */
 104 ChardevBackend *qemu_chr_parse_opts(QemuOpts *opts,
 105                                     Error **errp);
 106
 107 /**
 108  * qemu_chr_new:
 109  * @label: the name of the backend
 110  * @filename: the URI
 111  * @context: the #GMainContext to be used at initialization time
 112  *
 113  * Create a new character backend from a URI.
 114  * Do not implicitly initialize a monitor if the chardev is muxed.
 115  *
 116  * Returns: a new character backend
 117  */
 118 Chardev *qemu_chr_new(const char *label, const char *filename,
 119                       GMainContext *context);
 120
 121 /**
 122  * qemu_chr_new_mux_mon:
 123  * @label: the name of the backend
 124  * @filename: the URI
 125  * @context: the #GMainContext to be used at initialization time
 126  *
 127  * Create a new character backend from a URI.
 128  * Implicitly initialize a monitor if the chardev is muxed.
 129  *
 130  * Returns: a new character backend
 131  */
 132 Chardev *qemu_chr_new_mux_mon(const char *label, const char *filename,
 133                               GMainContext *context);
 134
 135 /**
 136 * qemu_chr_change:
 137 * @opts: the new backend options
 138  *
 139  * Change an existing character backend
 140  */
 141 void qemu_chr_change(QemuOpts *opts, Error **errp);
 142
 143 /**
 144  * qemu_chr_cleanup:
 145  *
 146  * Delete all chardevs (when leaving qemu)
 147  */
 148 void qemu_chr_cleanup(void);
 149
 150 /**
 151  * qemu_chr_new_noreplay:
 152  * @label: the name of the backend
 153  * @filename: the URI
 154  * @permit_mux_mon: if chardev is muxed, initialize a monitor
 155  * @context: the #GMainContext to be used at initialization time
 156  *
 157  * Create a new character backend from a URI.
 158  * Character device communications are not written
 159  * into the replay log.
 160  *
 161  * Returns: a new character backend
 162  */
 163 Chardev *qemu_chr_new_noreplay(const char *label, const char *filename,
 164                                bool permit_mux_mon, GMainContext *context);
 165
 166 /**
 167  * qemu_chr_be_can_write:
 168  *
 169  * Determine how much data the front end can currently accept.  This function
 170  * returns the number of bytes the front end can accept.  If it returns 0, the
 171  * front end cannot receive data at the moment.  The function must be polled
 172  * to determine when data can be received.
 173  *
 174  * Returns: the number of bytes the front end can receive via @qemu_chr_be_write
 175  */
 176 int qemu_chr_be_can_write(Chardev *s);
 177
 178 /**
 179  * qemu_chr_be_write:
 180  * @buf: a buffer to receive data from the front end
 181  * @len: the number of bytes to receive from the front end
 182  *
 183  * Write data from the back end to the front end.  Before issuing this call,
 184  * the caller should call @qemu_chr_be_can_write to determine how much data
 185  * the front end can currently accept.
 186  */
 187 void qemu_chr_be_write(Chardev *s, uint8_t *buf, int len);
 188
 189 /**
 190  * qemu_chr_be_write_impl:
 191  * @buf: a buffer to receive data from the front end
 192  * @len: the number of bytes to receive from the front end
 193  *
 194  * Implementation of back end writing. Used by replay module.
 195  */
 196 void qemu_chr_be_write_impl(Chardev *s, uint8_t *buf, int len);
 197
 198 /**
 199  * qemu_chr_be_update_read_handlers:
 200  * @context: the gcontext that will be used to attach the watch sources
 201  *
 202  * Invoked when frontend read handlers are setup
 203  */
 204 void qemu_chr_be_update_read_handlers(Chardev *s,
 205                                       GMainContext *context);
 206
 207 /**
 208  * qemu_chr_be_event:
 209  * @event: the event to send
 210  *
 211  * Send an event from the back end to the front end.
 212  */
 213 void qemu_chr_be_event(Chardev *s, QEMUChrEvent event);
 214
 215 int qemu_chr_add_client(Chardev *s, int fd);
 216 Chardev *qemu_chr_find(const char *name);
 217
 218 bool qemu_chr_has_feature(Chardev *chr,
 219                           ChardevFeature feature);
 220 void qemu_chr_set_feature(Chardev *chr,
 221                           ChardevFeature feature);
 222 QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename,
 223                                 bool permit_mux_mon);
 224 int qemu_chr_write(Chardev *s, const uint8_t *buf, int len, bool write_all);
 225 #define qemu_chr_write_all(s, buf, len) qemu_chr_write(s, buf, len, true)
 226 int qemu_chr_wait_connected(Chardev *chr, Error **errp);
 227
 228 #define TYPE_CHARDEV "chardev"
 229 OBJECT_DECLARE_TYPE(Chardev, ChardevClass, CHARDEV)
 230
 231 #define TYPE_CHARDEV_NULL "chardev-null"
 232 #define TYPE_CHARDEV_MUX "chardev-mux"
 233 #define TYPE_CHARDEV_RINGBUF "chardev-ringbuf"
 234 #define TYPE_CHARDEV_PTY "chardev-pty"
 235 #define TYPE_CHARDEV_CONSOLE "chardev-console"
 236 #define TYPE_CHARDEV_STDIO "chardev-stdio"
 237 #define TYPE_CHARDEV_PIPE "chardev-pipe"
 238 #define TYPE_CHARDEV_MEMORY "chardev-memory"
 239 #define TYPE_CHARDEV_PARALLEL "chardev-parallel"
 240 #define TYPE_CHARDEV_FILE "chardev-file"
 241 #define TYPE_CHARDEV_SERIAL "chardev-serial"
 242 #define TYPE_CHARDEV_SOCKET "chardev-socket"
 243 #define TYPE_CHARDEV_UDP "chardev-udp"
 244
 245 #define CHARDEV_IS_RINGBUF(chr) \
 246     object_dynamic_cast(OBJECT(chr), TYPE_CHARDEV_RINGBUF)
 247 #define CHARDEV_IS_PTY(chr) \
 248     object_dynamic_cast(OBJECT(chr), TYPE_CHARDEV_PTY)
 249
 250 struct ChardevClass {
 251     ObjectClass parent_class;
 252
 253     bool internal; /* TODO: eventually use TYPE_USER_CREATABLE */
 254     void (*parse)(QemuOpts *opts, ChardevBackend *backend, Error **errp);
 255
 256     void (*open)(Chardev *chr, ChardevBackend *backend,
 257                  bool *be_opened, Error **errp);
 258
 259     int (*chr_write)(Chardev *s, const uint8_t *buf, int len);
 260     int (*chr_sync_read)(Chardev *s, const uint8_t *buf, int len);
 261     GSource *(*chr_add_watch)(Chardev *s, GIOCondition cond);
 262     void (*chr_update_read_handler)(Chardev *s);
 263     int (*chr_ioctl)(Chardev *s, int cmd, void *arg);
 264     int (*get_msgfds)(Chardev *s, int* fds, int num);
 265     int (*set_msgfds)(Chardev *s, int *fds, int num);
 266     int (*chr_add_client)(Chardev *chr, int fd);
 267     int (*chr_wait_connected)(Chardev *chr, Error **errp);
 268     void (*chr_disconnect)(Chardev *chr);
 269     void (*chr_accept_input)(Chardev *chr);
 270     void (*chr_set_echo)(Chardev *chr, bool echo);
 271     void (*chr_set_fe_open)(Chardev *chr, int fe_open);
 272     void (*chr_be_event)(Chardev *s, QEMUChrEvent event);
 273     void (*chr_options_parsed)(Chardev *chr);
 274 };
 275
 276 Chardev *qemu_chardev_new(const char *id, const char *typename,
 277                           ChardevBackend *backend, GMainContext *context,
 278                           Error **errp);
 279
 280 extern int term_escape_char;
 281
 282 GSource *qemu_chr_timeout_add_ms(Chardev *chr, guint ms,
 283                                  GSourceFunc func, void *private);
 284
 285 void suspend_mux_open(void);
 286 void resume_mux_open(void);
 287
 288 /* console.c */
 289 void qemu_chr_parse_vc(QemuOpts *opts, ChardevBackend *backend, Error **errp);
 290
 291 #endif