qga/channel-posix.c

   1 #include "qemu/osdep.h"
   2 #include "qemu/cutils.h"
   3 #include <termios.h>
   4 #include "qapi/error.h"
   5 #include "qemu/sockets.h"
   6 #include "channel.h"
   7 #include "cutils.h"
   8
   9 #ifdef CONFIG_SOLARIS
  10 #include <stropts.h>
  11 #endif
  12
  13 #define GA_CHANNEL_BAUDRATE_DEFAULT B38400 /* for isa-serial channels */
  14
  15 struct GAChannel {
  16     GIOChannel *listen_channel;
  17     GIOChannel *client_channel;
  18     GAChannelMethod method;
  19     GAChannelCallback event_cb;
  20     gpointer user_data;
  21 };
  22
  23 static int ga_channel_client_add(GAChannel *c, int fd);
  24
  25 static gboolean ga_channel_listen_accept(GIOChannel *channel,
  26                                          GIOCondition condition, gpointer data)
  27 {
  28     GAChannel *c = data;
  29     int ret, client_fd;
  30     bool accepted = false;
  31
  32     g_assert(channel != NULL);
  33
  34     client_fd = qemu_accept(g_io_channel_unix_get_fd(channel), NULL, NULL);
  35     if (client_fd == -1) {
  36         g_warning("error converting fd to gsocket: %s", strerror(errno));
  37         goto out;
  38     }
  39     qemu_socket_set_nonblock(client_fd);
  40     ret = ga_channel_client_add(c, client_fd);
  41     if (ret) {
  42         g_warning("error setting up connection");
  43         close(client_fd);
  44         goto out;
  45     }
  46     accepted = true;
  47
  48 out:
  49     /* only accept 1 connection at a time */
  50     return !accepted;
  51 }
  52
  53 /* start polling for readable events on listen fd, new==true
  54  * indicates we should use the existing s->listen_channel
  55  */
  56 static void ga_channel_listen_add(GAChannel *c, int listen_fd, bool create)
  57 {
  58     if (create) {
  59         c->listen_channel = g_io_channel_unix_new(listen_fd);
  60     }
  61     g_io_add_watch(c->listen_channel, G_IO_IN, ga_channel_listen_accept, c);
  62 }
  63
  64 static void ga_channel_listen_close(GAChannel *c)
  65 {
  66     g_assert(c->listen_channel);
  67     g_io_channel_shutdown(c->listen_channel, true, NULL);
  68     g_io_channel_unref(c->listen_channel);
  69     c->listen_channel = NULL;
  70 }
  71
  72 /* cleanup state for closed connection/session, start accepting new
  73  * connections if we're in listening mode
  74  */
  75 static void ga_channel_client_close(GAChannel *c)
  76 {
  77     g_assert(c->client_channel);
  78     g_io_channel_shutdown(c->client_channel, true, NULL);
  79     g_io_channel_unref(c->client_channel);
  80     c->client_channel = NULL;
  81     if (c->listen_channel) {
  82         ga_channel_listen_add(c, 0, false);
  83     }
  84 }
  85
  86 static gboolean ga_channel_client_event(GIOChannel *channel,
  87                                         GIOCondition condition, gpointer data)
  88 {
  89     GAChannel *c = data;
  90     gboolean client_cont;
  91
  92     g_assert(c);
  93     if (c->event_cb) {
  94         client_cont = c->event_cb(condition, c->user_data);
  95         if (!client_cont) {
  96             ga_channel_client_close(c);
  97             return false;
  98         }
  99     }
 100     return true;
 101 }
 102
 103 static int ga_channel_client_add(GAChannel *c, int fd)
 104 {
 105     GIOChannel *client_channel;
 106     GError *err = NULL;
 107
 108     g_assert(c && !c->client_channel);
 109     client_channel = g_io_channel_unix_new(fd);
 110     g_assert(client_channel);
 111     g_io_channel_set_encoding(client_channel, NULL, &err);
 112     if (err != NULL) {
 113         g_warning("error setting channel encoding to binary");
 114         g_error_free(err);
 115         return -1;
 116     }
 117     g_io_add_watch(client_channel, G_IO_IN | G_IO_HUP,
 118                    ga_channel_client_event, c);
 119     c->client_channel = client_channel;
 120     return 0;
 121 }
 122
 123 static gboolean ga_channel_open(GAChannel *c, const gchar *path,
 124                                 GAChannelMethod method, int fd, Error **errp)
 125 {
 126     int ret;
 127     c->method = method;
 128
 129     switch (c->method) {
 130     case GA_CHANNEL_VIRTIO_SERIAL: {
 131         assert(fd < 0);
 132         fd = qga_open_cloexec(
 133             path,
 134 #ifndef CONFIG_SOLARIS
 135             O_ASYNC |
 136 #endif
 137             O_RDWR | O_NONBLOCK,
 138             0
 139         );
 140         if (fd == -1) {
 141             error_setg_errno(errp, errno, "error opening channel");
 142             return false;
 143         }
 144 #ifdef CONFIG_SOLARIS
 145         ret = ioctl(fd, I_SETSIG, S_OUTPUT | S_INPUT | S_HIPRI);
 146         if (ret == -1) {
 147             error_setg_errno(errp, errno, "error setting event mask for channel");
 148             close(fd);
 149             return false;
 150         }
 151 #endif
 152         ret = ga_channel_client_add(c, fd);
 153         if (ret) {
 154             error_setg(errp, "error adding channel to main loop");
 155             close(fd);
 156             return false;
 157         }
 158         break;
 159     }
 160     case GA_CHANNEL_ISA_SERIAL: {
 161         struct termios tio;
 162
 163         assert(fd < 0);
 164         fd = qga_open_cloexec(path, O_RDWR | O_NOCTTY | O_NONBLOCK, 0);
 165         if (fd == -1) {
 166             error_setg_errno(errp, errno, "error opening channel");
 167             return false;
 168         }
 169         tcgetattr(fd, &tio);
 170         /* set up serial port for non-canonical, dumb byte streaming */
 171         tio.c_iflag &= ~(IGNBRK | BRKINT | IGNPAR | PARMRK | INPCK | ISTRIP |
 172                          INLCR | IGNCR | ICRNL | IXON | IXOFF | IXANY |
 173                          IMAXBEL);
 174         tio.c_oflag = 0;
 175         tio.c_lflag = 0;
 176         tio.c_cflag |= GA_CHANNEL_BAUDRATE_DEFAULT;
 177         /* 1 available byte min or reads will block (we'll set non-blocking
 178          * elsewhere, else we have to deal with read()=0 instead)
 179          */
 180         tio.c_cc[VMIN] = 1;
 181         tio.c_cc[VTIME] = 0;
 182         /* flush everything waiting for read/xmit, it's garbage at this point */
 183         tcflush(fd, TCIFLUSH);
 184         tcsetattr(fd, TCSANOW, &tio);
 185         ret = ga_channel_client_add(c, fd);
 186         if (ret) {
 187             error_setg(errp, "error adding channel to main loop");
 188             close(fd);
 189             return false;
 190         }
 191         break;
 192     }
 193     case GA_CHANNEL_UNIX_LISTEN: {
 194         if (fd < 0) {
 195             fd = unix_listen(path, errp);
 196             if (fd < 0) {
 197                 return false;
 198             }
 199         }
 200         ga_channel_listen_add(c, fd, true);
 201         break;
 202     }
 203     case GA_CHANNEL_VSOCK_LISTEN: {
 204         if (fd < 0) {
 205             SocketAddress *addr;
 206             char *addr_str;
 207
 208             addr_str = g_strdup_printf("vsock:%s", path);
 209             addr = socket_parse(addr_str, errp);
 210             g_free(addr_str);
 211             if (!addr) {
 212                 return false;
 213             }
 214
 215             fd = socket_listen(addr, 1, errp);
 216             qapi_free_SocketAddress(addr);
 217             if (fd < 0) {
 218                 return false;
 219             }
 220         }
 221         ga_channel_listen_add(c, fd, true);
 222         break;
 223     }
 224     default:
 225         error_setg(errp, "error binding/listening to specified socket");
 226         return false;
 227     }
 228
 229     return true;
 230 }
 231
 232 GIOStatus ga_channel_write_all(GAChannel *c, const gchar *buf, gsize size)
 233 {
 234     GError *err = NULL;
 235     gsize written = 0;
 236     GIOStatus status = G_IO_STATUS_NORMAL;
 237
 238     while (size) {
 239         g_debug("sending data, count: %d", (int)size);
 240         status = g_io_channel_write_chars(c->client_channel, buf, size,
 241                                           &written, &err);
 242         if (status == G_IO_STATUS_NORMAL) {
 243             size -= written;
 244             buf += written;
 245         } else if (status != G_IO_STATUS_AGAIN) {
 246             g_warning("error writing to channel: %s", err->message);
 247             return status;
 248         }
 249     }
 250
 251     do {
 252         status = g_io_channel_flush(c->client_channel, &err);
 253     } while (status == G_IO_STATUS_AGAIN);
 254
 255     if (status != G_IO_STATUS_NORMAL) {
 256         g_warning("error flushing channel: %s", err->message);
 257     }
 258
 259     return status;
 260 }
 261
 262 GIOStatus ga_channel_read(GAChannel *c, gchar *buf, gsize size, gsize *count)
 263 {
 264     return g_io_channel_read_chars(c->client_channel, buf, size, count, NULL);
 265 }
 266
 267 GAChannel *ga_channel_new(GAChannelMethod method, const gchar *path,
 268                           int listen_fd, GAChannelCallback cb, gpointer opaque)
 269 {
 270     Error *err = NULL;
 271     GAChannel *c = g_new0(GAChannel, 1);
 272     c->event_cb = cb;
 273     c->user_data = opaque;
 274
 275     if (!ga_channel_open(c, path, method, listen_fd, &err)) {
 276         g_critical("%s", error_get_pretty(err));
 277         error_free(err);
 278         ga_channel_free(c);
 279         return NULL;
 280     }
 281
 282     return c;
 283 }
 284
 285 void ga_channel_free(GAChannel *c)
 286 {
 287     if (c->listen_channel) {
 288         ga_channel_listen_close(c);
 289     }
 290     if (c->client_channel) {
 291         ga_channel_client_close(c);
 292     }
 293     g_free(c);
 294 }