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
  51     QEMU_CHAR_FEATURE_LAST,
  52 } ChardevFeature;
  53
  54 #define qemu_chr_replay(chr) qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_REPLAY)
  55
  56 struct Chardev {
  57     Object parent_obj;
  58
  59     QemuMutex chr_write_lock;
  60     CharBackend *be;
  61     char *label;
  62     char *filename;
  63     int logfd;
  64     int be_open;
  65     GSource *gsource;
  66     GMainContext *gcontext;
  67     DECLARE_BITMAP(features, QEMU_CHAR_FEATURE_LAST);
  68 };
  69
  70 /**
  71  * @qemu_chr_new_from_opts:
  72  *
  73  * Create a new character backend from a QemuOpts list.
  74  *
  75  * @opts see qemu-config.c for a list of valid options
  76  *
  77  * Returns: on success: a new character backend
  78  *          otherwise:  NULL; @errp specifies the error
  79  *                            or left untouched in case of help option
  80  */
  81 Chardev *qemu_chr_new_from_opts(QemuOpts *opts,
  82                                 Error **errp);
  83
  84 /**
  85  * @qemu_chr_parse_common:
  86  *
  87  * Parse the common options available to all character backends.
  88  *
  89  * @opts the options that still need parsing
  90  * @backend a new backend
  91  */
  92 void qemu_chr_parse_common(QemuOpts *opts, ChardevCommon *backend);
  93
  94 /**
  95  * @qemu_chr_parse_opts:
  96  *
  97  * Parse the options to the ChardevBackend struct.
  98  *
  99  * Returns: a new backend or NULL on error
 100  */
 101 ChardevBackend *qemu_chr_parse_opts(QemuOpts *opts,
 102                                     Error **errp);
 103
 104 /**
 105  * @qemu_chr_new:
 106  *
 107  * Create a new character backend from a URI.
 108  *
 109  * @label the name of the backend
 110  * @filename the URI
 111  *
 112  * Returns: a new character backend
 113  */
 114 Chardev *qemu_chr_new(const char *label, const char *filename);
 115
 116 /**
 117  * @qemu_chr_change:
 118  *
 119  * Change an existing character backend
 120  *
 121  * @opts the new backend options
 122  */
 123 void qemu_chr_change(QemuOpts *opts, Error **errp);
 124
 125 /**
 126  * @qemu_chr_cleanup:
 127  *
 128  * Delete all chardevs (when leaving qemu)
 129  */
 130 void qemu_chr_cleanup(void);
 131
 132 /**
 133  * @qemu_chr_new_noreplay:
 134  *
 135  * Create a new character backend from a URI.
 136  * Character device communications are not written
 137  * into the replay log.
 138  *
 139  * @label the name of the backend
 140  * @filename the URI
 141  *
 142  * Returns: a new character backend
 143  */
 144 Chardev *qemu_chr_new_noreplay(const char *label, const char *filename);
 145
 146 /**
 147  * @qemu_chr_be_can_write:
 148  *
 149  * Determine how much data the front end can currently accept.  This function
 150  * returns the number of bytes the front end can accept.  If it returns 0, the
 151  * front end cannot receive data at the moment.  The function must be polled
 152  * to determine when data can be received.
 153  *
 154  * Returns: the number of bytes the front end can receive via @qemu_chr_be_write
 155  */
 156 int qemu_chr_be_can_write(Chardev *s);
 157
 158 /**
 159  * @qemu_chr_be_write:
 160  *
 161  * Write data from the back end to the front end.  Before issuing this call,
 162  * the caller should call @qemu_chr_be_can_write to determine how much data
 163  * the front end can currently accept.
 164  *
 165  * @buf a buffer to receive data from the front end
 166  * @len the number of bytes to receive from the front end
 167  */
 168 void qemu_chr_be_write(Chardev *s, uint8_t *buf, int len);
 169
 170 /**
 171  * @qemu_chr_be_write_impl:
 172  *
 173  * Implementation of back end writing. Used by replay module.
 174  *
 175  * @buf a buffer to receive data from the front end
 176  * @len the number of bytes to receive from the front end
 177  */
 178 void qemu_chr_be_write_impl(Chardev *s, uint8_t *buf, int len);
 179
 180 /**
 181  * @qemu_chr_be_update_read_handlers:
 182  *
 183  * Invoked when frontend read handlers are setup
 184  *
 185  * @context the gcontext that will be used to attach the watch sources
 186  */
 187 void qemu_chr_be_update_read_handlers(Chardev *s,
 188                                       GMainContext *context);
 189
 190 /**
 191  * @qemu_chr_be_event:
 192  *
 193  * Send an event from the back end to the front end.
 194  *
 195  * @event the event to send
 196  */
 197 void qemu_chr_be_event(Chardev *s, int event);
 198
 199 int qemu_chr_add_client(Chardev *s, int fd);
 200 Chardev *qemu_chr_find(const char *name);
 201
 202 bool qemu_chr_has_feature(Chardev *chr,
 203                           ChardevFeature feature);
 204 void qemu_chr_set_feature(Chardev *chr,
 205                           ChardevFeature feature);
 206 QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename);
 207 int qemu_chr_write(Chardev *s, const uint8_t *buf, int len, bool write_all);
 208 #define qemu_chr_write_all(s, buf, len) qemu_chr_write(s, buf, len, true)
 209 int qemu_chr_wait_connected(Chardev *chr, Error **errp);
 210
 211 #define TYPE_CHARDEV "chardev"
 212 #define CHARDEV(obj) OBJECT_CHECK(Chardev, (obj), TYPE_CHARDEV)
 213 #define CHARDEV_CLASS(klass) \
 214     OBJECT_CLASS_CHECK(ChardevClass, (klass), TYPE_CHARDEV)
 215 #define CHARDEV_GET_CLASS(obj) \
 216     OBJECT_GET_CLASS(ChardevClass, (obj), TYPE_CHARDEV)
 217
 218 #define TYPE_CHARDEV_NULL "chardev-null"
 219 #define TYPE_CHARDEV_MUX "chardev-mux"
 220 #define TYPE_CHARDEV_RINGBUF "chardev-ringbuf"
 221 #define TYPE_CHARDEV_PTY "chardev-pty"
 222 #define TYPE_CHARDEV_CONSOLE "chardev-console"
 223 #define TYPE_CHARDEV_STDIO "chardev-stdio"
 224 #define TYPE_CHARDEV_PIPE "chardev-pipe"
 225 #define TYPE_CHARDEV_MEMORY "chardev-memory"
 226 #define TYPE_CHARDEV_PARALLEL "chardev-parallel"
 227 #define TYPE_CHARDEV_FILE "chardev-file"
 228 #define TYPE_CHARDEV_SERIAL "chardev-serial"
 229 #define TYPE_CHARDEV_SOCKET "chardev-socket"
 230 #define TYPE_CHARDEV_UDP "chardev-udp"
 231
 232 #define CHARDEV_IS_RINGBUF(chr) \
 233     object_dynamic_cast(OBJECT(chr), TYPE_CHARDEV_RINGBUF)
 234 #define CHARDEV_IS_PTY(chr) \
 235     object_dynamic_cast(OBJECT(chr), TYPE_CHARDEV_PTY)
 236
 237 typedef struct ChardevClass {
 238     ObjectClass parent_class;
 239
 240     bool internal; /* TODO: eventually use TYPE_USER_CREATABLE */
 241     void (*parse)(QemuOpts *opts, ChardevBackend *backend, Error **errp);
 242
 243     void (*open)(Chardev *chr, ChardevBackend *backend,
 244                  bool *be_opened, Error **errp);
 245
 246     int (*chr_write)(Chardev *s, const uint8_t *buf, int len);
 247     int (*chr_sync_read)(Chardev *s, const uint8_t *buf, int len);
 248     GSource *(*chr_add_watch)(Chardev *s, GIOCondition cond);
 249     void (*chr_update_read_handler)(Chardev *s);
 250     int (*chr_ioctl)(Chardev *s, int cmd, void *arg);
 251     int (*get_msgfds)(Chardev *s, int* fds, int num);
 252     int (*set_msgfds)(Chardev *s, int *fds, int num);
 253     int (*chr_add_client)(Chardev *chr, int fd);
 254     int (*chr_wait_connected)(Chardev *chr, Error **errp);
 255     void (*chr_disconnect)(Chardev *chr);
 256     void (*chr_accept_input)(Chardev *chr);
 257     void (*chr_set_echo)(Chardev *chr, bool echo);
 258     void (*chr_set_fe_open)(Chardev *chr, int fe_open);
 259     void (*chr_be_event)(Chardev *s, int event);
 260     /* Return 0 if succeeded, 1 if failed */
 261     int (*chr_machine_done)(Chardev *chr);
 262 } ChardevClass;
 263
 264 Chardev *qemu_chardev_new(const char *id, const char *typename,
 265                           ChardevBackend *backend, Error **errp);
 266
 267 extern int term_escape_char;
 268
 269 GSource *qemu_chr_timeout_add_ms(Chardev *chr, guint ms,
 270                                  GSourceFunc func, void *private);
 271
 272 /* console.c */
 273 void qemu_chr_parse_vc(QemuOpts *opts, ChardevBackend *backend, Error **errp);
 274
 275 #endif