include/chardev/char.h

   1 #ifndef QEMU_CHAR_H
   2 #define QEMU_CHAR_H
   3
   4 #include "qemu-common.h"
   5 #include "qemu/option.h"
   6 #include "qemu/main-loop.h"
   7 #include "qemu/bitmap.h"
   8 #include "qom/object.h"
   9
  10 #define IAC_EOR 239
  11 #define IAC_SE 240
  12 #define IAC_NOP 241
  13 #define IAC_BREAK 243
  14 #define IAC_IP 244
  15 #define IAC_SB 250
  16 #define IAC 255
  17
  18 /* character device */
  19 typedef struct CharBackend CharBackend;
  20
  21 typedef enum {
  22     CHR_EVENT_BREAK, /* serial break char */
  23     CHR_EVENT_OPENED, /* new connection established */
  24     CHR_EVENT_MUX_IN, /* mux-focus was set to this terminal */
  25     CHR_EVENT_MUX_OUT, /* mux-focus will move on */
  26     CHR_EVENT_CLOSED /* connection closed */
  27 } QEMUChrEvent;
  28
  29 #define CHR_READ_BUF_LEN 4096
  30
  31 typedef enum {
  32     /* Whether the chardev peer is able to close and
  33      * reopen the data channel, thus requiring support
  34      * for qemu_chr_wait_connected() to wait for a
  35      * valid connection */
  36     QEMU_CHAR_FEATURE_RECONNECTABLE,
  37     /* Whether it is possible to send/recv file descriptors
  38      * over the data channel */
  39     QEMU_CHAR_FEATURE_FD_PASS,
  40     /* Whether replay or record mode is enabled */
  41     QEMU_CHAR_FEATURE_REPLAY,
  42
  43     QEMU_CHAR_FEATURE_LAST,
  44 } ChardevFeature;
  45
  46 #define qemu_chr_replay(chr) qemu_chr_has_feature(chr, QEMU_CHAR_FEATURE_REPLAY)
  47
  48 struct Chardev {
  49     Object parent_obj;
  50
  51     QemuMutex chr_write_lock;
  52     CharBackend *be;
  53     char *label;
  54     char *filename;
  55     int logfd;
  56     int be_open;
  57     GSource *gsource;
  58     DECLARE_BITMAP(features, QEMU_CHAR_FEATURE_LAST);
  59 };
  60
  61 /**
  62  * @qemu_chr_new_from_opts:
  63  *
  64  * Create a new character backend from a QemuOpts list.
  65  *
  66  * @opts see qemu-config.c for a list of valid options
  67  *
  68  * Returns: on success: a new character backend
  69  *          otherwise:  NULL; @errp specifies the error
  70  *                            or left untouched in case of help option
  71  */
  72 Chardev *qemu_chr_new_from_opts(QemuOpts *opts,
  73                                 Error **errp);
  74
  75 /**
  76  * @qemu_chr_parse_common:
  77  *
  78  * Parse the common options available to all character backends.
  79  *
  80  * @opts the options that still need parsing
  81  * @backend a new backend
  82  */
  83 void qemu_chr_parse_common(QemuOpts *opts, ChardevCommon *backend);
  84
  85 /**
  86  * @qemu_chr_parse_opts:
  87  *
  88  * Parse the options to the ChardevBackend struct.
  89  *
  90  * Returns: a new backend or NULL on error
  91  */
  92 ChardevBackend *qemu_chr_parse_opts(QemuOpts *opts,
  93                                     Error **errp);
  94
  95 /**
  96  * @qemu_chr_new:
  97  *
  98  * Create a new character backend from a URI.
  99  *
 100  * @label the name of the backend
 101  * @filename the URI
 102  *
 103  * Returns: a new character backend
 104  */
 105 Chardev *qemu_chr_new(const char *label, const char *filename);
 106
 107 /**
 108  * @qemu_chr_change:
 109  *
 110  * Change an existing character backend
 111  *
 112  * @opts the new backend options
 113  */
 114 void qemu_chr_change(QemuOpts *opts, Error **errp);
 115
 116 /**
 117  * @qemu_chr_cleanup:
 118  *
 119  * Delete all chardevs (when leaving qemu)
 120  */
 121 void qemu_chr_cleanup(void);
 122
 123 /**
 124  * @qemu_chr_new_noreplay:
 125  *
 126  * Create a new character backend from a URI.
 127  * Character device communications are not written
 128  * into the replay log.
 129  *
 130  * @label the name of the backend
 131  * @filename the URI
 132  *
 133  * Returns: a new character backend
 134  */
 135 Chardev *qemu_chr_new_noreplay(const char *label, const char *filename);
 136
 137 /**
 138  * @qemu_chr_be_can_write:
 139  *
 140  * Determine how much data the front end can currently accept.  This function
 141  * returns the number of bytes the front end can accept.  If it returns 0, the
 142  * front end cannot receive data at the moment.  The function must be polled
 143  * to determine when data can be received.
 144  *
 145  * Returns: the number of bytes the front end can receive via @qemu_chr_be_write
 146  */
 147 int qemu_chr_be_can_write(Chardev *s);
 148
 149 /**
 150  * @qemu_chr_be_write:
 151  *
 152  * Write data from the back end to the front end.  Before issuing this call,
 153  * the caller should call @qemu_chr_be_can_write to determine how much data
 154  * the front end can currently accept.
 155  *
 156  * @buf a buffer to receive data from the front end
 157  * @len the number of bytes to receive from the front end
 158  */
 159 void qemu_chr_be_write(Chardev *s, uint8_t *buf, int len);
 160
 161 /**
 162  * @qemu_chr_be_write_impl:
 163  *
 164  * Implementation of back end writing. Used by replay module.
 165  *
 166  * @buf a buffer to receive data from the front end
 167  * @len the number of bytes to receive from the front end
 168  */
 169 void qemu_chr_be_write_impl(Chardev *s, uint8_t *buf, int len);
 170
 171 /**
 172  * @qemu_chr_be_update_read_handlers:
 173  *
 174  * Invoked when frontend read handlers are setup
 175  *
 176  * @context the gcontext that will be used to attach the watch sources
 177  */
 178 void qemu_chr_be_update_read_handlers(Chardev *s,
 179                                       GMainContext *context);
 180
 181 /**
 182  * @qemu_chr_be_event:
 183  *
 184  * Send an event from the back end to the front end.
 185  *
 186  * @event the event to send
 187  */
 188 void qemu_chr_be_event(Chardev *s, int event);
 189
 190 int qemu_chr_add_client(Chardev *s, int fd);
 191 Chardev *qemu_chr_find(const char *name);
 192
 193 bool qemu_chr_has_feature(Chardev *chr,
 194                           ChardevFeature feature);
 195 void qemu_chr_set_feature(Chardev *chr,
 196                           ChardevFeature feature);
 197 QemuOpts *qemu_chr_parse_compat(const char *label, const char *filename);
 198 int qemu_chr_write(Chardev *s, const uint8_t *buf, int len, bool write_all);
 199 #define qemu_chr_write_all(s, buf, len) qemu_chr_write(s, buf, len, true)
 200 int qemu_chr_wait_connected(Chardev *chr, Error **errp);
 201
 202 #define TYPE_CHARDEV "chardev"
 203 #define CHARDEV(obj) OBJECT_CHECK(Chardev, (obj), TYPE_CHARDEV)
 204 #define CHARDEV_CLASS(klass) \
 205     OBJECT_CLASS_CHECK(ChardevClass, (klass), TYPE_CHARDEV)
 206 #define CHARDEV_GET_CLASS(obj) \
 207     OBJECT_GET_CLASS(ChardevClass, (obj), TYPE_CHARDEV)
 208
 209 #define TYPE_CHARDEV_NULL "chardev-null"
 210 #define TYPE_CHARDEV_MUX "chardev-mux"
 211 #define TYPE_CHARDEV_RINGBUF "chardev-ringbuf"
 212 #define TYPE_CHARDEV_PTY "chardev-pty"
 213 #define TYPE_CHARDEV_CONSOLE "chardev-console"
 214 #define TYPE_CHARDEV_STDIO "chardev-stdio"
 215 #define TYPE_CHARDEV_PIPE "chardev-pipe"
 216 #define TYPE_CHARDEV_MEMORY "chardev-memory"
 217 #define TYPE_CHARDEV_PARALLEL "chardev-parallel"
 218 #define TYPE_CHARDEV_FILE "chardev-file"
 219 #define TYPE_CHARDEV_SERIAL "chardev-serial"
 220 #define TYPE_CHARDEV_SOCKET "chardev-socket"
 221 #define TYPE_CHARDEV_UDP "chardev-udp"
 222
 223 #define CHARDEV_IS_RINGBUF(chr) \
 224     object_dynamic_cast(OBJECT(chr), TYPE_CHARDEV_RINGBUF)
 225 #define CHARDEV_IS_PTY(chr) \
 226     object_dynamic_cast(OBJECT(chr), TYPE_CHARDEV_PTY)
 227
 228 typedef struct ChardevClass {
 229     ObjectClass parent_class;
 230
 231     bool internal; /* TODO: eventually use TYPE_USER_CREATABLE */
 232     void (*parse)(QemuOpts *opts, ChardevBackend *backend, Error **errp);
 233
 234     void (*open)(Chardev *chr, ChardevBackend *backend,
 235                  bool *be_opened, Error **errp);
 236
 237     int (*chr_write)(Chardev *s, const uint8_t *buf, int len);
 238     int (*chr_sync_read)(Chardev *s, const uint8_t *buf, int len);
 239     GSource *(*chr_add_watch)(Chardev *s, GIOCondition cond);
 240     void (*chr_update_read_handler)(Chardev *s, GMainContext *context);
 241     int (*chr_ioctl)(Chardev *s, int cmd, void *arg);
 242     int (*get_msgfds)(Chardev *s, int* fds, int num);
 243     int (*set_msgfds)(Chardev *s, int *fds, int num);
 244     int (*chr_add_client)(Chardev *chr, int fd);
 245     int (*chr_wait_connected)(Chardev *chr, Error **errp);
 246     void (*chr_disconnect)(Chardev *chr);
 247     void (*chr_accept_input)(Chardev *chr);
 248     void (*chr_set_echo)(Chardev *chr, bool echo);
 249     void (*chr_set_fe_open)(Chardev *chr, int fe_open);
 250 } ChardevClass;
 251
 252 Chardev *qemu_chardev_new(const char *id, const char *typename,
 253                           ChardevBackend *backend, Error **errp);
 254
 255 extern int term_escape_char;
 256
 257 /* console.c */
 258 void qemu_chr_parse_vc(QemuOpts *opts, ChardevBackend *backend, Error **errp);
 259
 260 #endif