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