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/main-loop.h"
   6 #include "qemu/bitmap.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  *
  77  * Create a new character backend from a QemuOpts list.
  78  *
  79  * Returns: on success: a new character backend
  80  *          otherwise:  NULL; @errp specifies the error
  81  *                            or left untouched in case of help option
  82  */
  83 Chardev *qemu_chr_new_from_opts(QemuOpts *opts,
  84                                 Error **errp);
  85
  86 /**
  87  * qemu_chr_parse_common:
  88  * @opts: the options that still need parsing
  89  * @backend: a new backend
  90  *
  91  * Parse the common options available to all character backends.
  92  */
  93 void qemu_chr_parse_common(QemuOpts *opts, ChardevCommon *backend);
  94
  95 /**
  96  * qemu_chr_parse_opts:
  97  *
  98  * Parse the options to the ChardevBackend struct.
  99  *
 100  * Returns: a new backend or NULL on error
 101  */
 102 ChardevBackend *qemu_chr_parse_opts(QemuOpts *opts,
 103                                     Error **errp);
 104
 105 /**
 106  * qemu_chr_new:
 107  * @label: the name of the backend
 108  * @filename: the URI
 109  *
 110  * Create a new character backend from a URI.
 111  * Do not implicitly initialize a monitor if the chardev is muxed.
 112  *
 113  * Returns: a new character backend
 114  */
 115 Chardev *qemu_chr_new(const char *label, const char *filename);
 116
 117 /**
 118  * qemu_chr_new_mux_mon:
 119  * @label: the name of the backend
 120  * @filename: the URI
 121  *
 122  * Create a new character backend from a URI.
 123  * Implicitly initialize a monitor if the chardev is muxed.
 124  *
 125  * Returns: a new character backend
 126  */
 127 Chardev *qemu_chr_new_mux_mon(const char *label, const char *filename);
 128
 129 /**
 130 * qemu_chr_change:
 131 * @opts: the new backend options
 132  *
 133  * Change an existing character backend
 134  */
 135 void qemu_chr_change(QemuOpts *opts, Error **errp);
 136
 137 /**
 138  * qemu_chr_cleanup:
 139  *
 140  * Delete all chardevs (when leaving qemu)
 141  */
 142 void qemu_chr_cleanup(void);
 143
 144 /**
 145  * qemu_chr_new_noreplay:
 146  * @label: the name of the backend
 147  * @filename: the URI
 148  * @permit_mux_mon: if chardev is muxed, initialize a monitor
 149  *
 150  * Create a new character backend from a URI.
 151  * Character device communications are not written
 152  * into the replay log.
 153  *
 154  * Returns: a new character backend
 155  */
 156 Chardev *qemu_chr_new_noreplay(const char *label, const char *filename,
 157                                bool permit_mux_mon);
 158
 159 /**
 160  * qemu_chr_be_can_write:
 161  *
 162  * Determine how much data the front end can currently accept.  This function
 163  * returns the number of bytes the front end can accept.  If it returns 0, the
 164  * front end cannot receive data at the moment.  The function must be polled
 165  * to determine when data can be received.
 166  *
 167  * Returns: the number of bytes the front end can receive via @qemu_chr_be_write
 168  */
 169 int qemu_chr_be_can_write(Chardev *s);
 170
 171 /**
 172  * qemu_chr_be_write:
 173  * @buf: a buffer to receive data from the front end
 174  * @len: the number of bytes to receive from the front end
 175  *
 176  * Write data from the back end to the front end.  Before issuing this call,
 177  * the caller should call @qemu_chr_be_can_write to determine how much data
 178  * the front end can currently accept.
 179  */
 180 void qemu_chr_be_write(Chardev *s, uint8_t *buf, int len);
 181
 182 /**
 183  * qemu_chr_be_write_impl:
 184  * @buf: a buffer to receive data from the front end
 185  * @len: the number of bytes to receive from the front end
 186  *
 187  * Implementation of back end writing. Used by replay module.
 188  */
 189 void qemu_chr_be_write_impl(Chardev *s, uint8_t *buf, int len);
 190
 191 /**
 192  * qemu_chr_be_update_read_handlers:
 193  * @context: the gcontext that will be used to attach the watch sources
 194  *
 195  * Invoked when frontend read handlers are setup
 196  */
 197 void qemu_chr_be_update_read_handlers(Chardev *s,
 198                                       GMainContext *context);
 199
 200 /**
 201  * qemu_chr_be_event:
 202  * @event: the event to send
 203  *
 204  * Send an event from the back end to the front end.
 205  */
 206 void qemu_chr_be_event(Chardev *s, int event);
 207
 208 int qemu_chr_add_client(Chardev *s, int fd);
 209 Chardev *qemu_chr_find(const char *name);
 210
 211 bool qemu_chr_has_feature(Chardev *chr,
 212                           ChardevFeature feature);
 213 void qemu_chr_set_feature(Chardev *chr,
 214                           ChardevFeature feature);
 215 QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename,
 216                                 bool permit_mux_mon);
 217 int qemu_chr_write(Chardev *s, const uint8_t *buf, int len, bool write_all);
 218 #define qemu_chr_write_all(s, buf, len) qemu_chr_write(s, buf, len, true)
 219 int qemu_chr_wait_connected(Chardev *chr, Error **errp);
 220
 221 #define TYPE_CHARDEV "chardev"
 222 #define CHARDEV(obj) OBJECT_CHECK(Chardev, (obj), TYPE_CHARDEV)
 223 #define CHARDEV_CLASS(klass) \
 224     OBJECT_CLASS_CHECK(ChardevClass, (klass), TYPE_CHARDEV)
 225 #define CHARDEV_GET_CLASS(obj) \
 226     OBJECT_GET_CLASS(ChardevClass, (obj), TYPE_CHARDEV)
 227
 228 #define TYPE_CHARDEV_NULL "chardev-null"
 229 #define TYPE_CHARDEV_MUX "chardev-mux"
 230 #define TYPE_CHARDEV_RINGBUF "chardev-ringbuf"
 231 #define TYPE_CHARDEV_PTY "chardev-pty"
 232 #define TYPE_CHARDEV_CONSOLE "chardev-console"
 233 #define TYPE_CHARDEV_STDIO "chardev-stdio"
 234 #define TYPE_CHARDEV_PIPE "chardev-pipe"
 235 #define TYPE_CHARDEV_MEMORY "chardev-memory"
 236 #define TYPE_CHARDEV_PARALLEL "chardev-parallel"
 237 #define TYPE_CHARDEV_FILE "chardev-file"
 238 #define TYPE_CHARDEV_SERIAL "chardev-serial"
 239 #define TYPE_CHARDEV_SOCKET "chardev-socket"
 240 #define TYPE_CHARDEV_UDP "chardev-udp"
 241
 242 #define CHARDEV_IS_RINGBUF(chr) \
 243     object_dynamic_cast(OBJECT(chr), TYPE_CHARDEV_RINGBUF)
 244 #define CHARDEV_IS_PTY(chr) \
 245     object_dynamic_cast(OBJECT(chr), TYPE_CHARDEV_PTY)
 246
 247 typedef struct ChardevClass {
 248     ObjectClass parent_class;
 249
 250     bool internal; /* TODO: eventually use TYPE_USER_CREATABLE */
 251     void (*parse)(QemuOpts *opts, ChardevBackend *backend, Error **errp);
 252
 253     void (*open)(Chardev *chr, ChardevBackend *backend,
 254                  bool *be_opened, Error **errp);
 255
 256     int (*chr_write)(Chardev *s, const uint8_t *buf, int len);
 257     int (*chr_sync_read)(Chardev *s, const uint8_t *buf, int len);
 258     GSource *(*chr_add_watch)(Chardev *s, GIOCondition cond);
 259     void (*chr_update_read_handler)(Chardev *s);
 260     int (*chr_ioctl)(Chardev *s, int cmd, void *arg);
 261     int (*get_msgfds)(Chardev *s, int* fds, int num);
 262     int (*set_msgfds)(Chardev *s, int *fds, int num);
 263     int (*chr_add_client)(Chardev *chr, int fd);
 264     int (*chr_wait_connected)(Chardev *chr, Error **errp);
 265     void (*chr_disconnect)(Chardev *chr);
 266     void (*chr_accept_input)(Chardev *chr);
 267     void (*chr_set_echo)(Chardev *chr, bool echo);
 268     void (*chr_set_fe_open)(Chardev *chr, int fe_open);
 269     void (*chr_be_event)(Chardev *s, int event);
 270     /* Return 0 if succeeded, 1 if failed */
 271     int (*chr_machine_done)(Chardev *chr);
 272 } ChardevClass;
 273
 274 Chardev *qemu_chardev_new(const char *id, const char *typename,
 275                           ChardevBackend *backend, Error **errp);
 276
 277 extern int term_escape_char;
 278
 279 GSource *qemu_chr_timeout_add_ms(Chardev *chr, guint ms,
 280                                  GSourceFunc func, void *private);
 281
 282 /* console.c */
 283 void qemu_chr_parse_vc(QemuOpts *opts, ChardevBackend *backend, Error **errp);
 284
 285 #endif