xref: /qemu/qga/channel-posix.c (revision b88651cb4d4fa416fdbb6afaf5b26ec8c035eaad)
1  #include "qemu/osdep.h"
2  #include <termios.h>
3  #include "qapi/error.h"
4  #include "qemu/sockets.h"
5  #include "channel.h"
6  
7  #ifdef CONFIG_SOLARIS
8  #include <stropts.h>
9  #endif
10  
11  #define GA_CHANNEL_BAUDRATE_DEFAULT B38400 /* for isa-serial channels */
12  
13  struct GAChannel {
14      GIOChannel *listen_channel;
15      GIOChannel *client_channel;
16      GAChannelMethod method;
17      GAChannelCallback event_cb;
18      gpointer user_data;
19  };
20  
21  static int ga_channel_client_add(GAChannel *c, int fd);
22  
23  static gboolean ga_channel_listen_accept(GIOChannel *channel,
24                                           GIOCondition condition, gpointer data)
25  {
26      GAChannel *c = data;
27      int ret, client_fd;
28      bool accepted = false;
29  
30      g_assert(channel != NULL);
31  
32      client_fd = qemu_accept(g_io_channel_unix_get_fd(channel), NULL, NULL);
33      if (client_fd == -1) {
34          g_warning("error converting fd to gsocket: %s", strerror(errno));
35          goto out;
36      }
37      qemu_socket_set_nonblock(client_fd);
38      ret = ga_channel_client_add(c, client_fd);
39      if (ret) {
40          g_warning("error setting up connection");
41          close(client_fd);
42          goto out;
43      }
44      accepted = true;
45  
46  out:
47      /* only accept 1 connection at a time */
48      return !accepted;
49  }
50  
51  /* start polling for readable events on listen fd, new==true
52   * indicates we should use the existing s->listen_channel
53   */
54  static void ga_channel_listen_add(GAChannel *c, int listen_fd, bool create)
55  {
56      if (create) {
57          c->listen_channel = g_io_channel_unix_new(listen_fd);
58      }
59      g_io_add_watch(c->listen_channel, G_IO_IN, ga_channel_listen_accept, c);
60  }
61  
62  static void ga_channel_listen_close(GAChannel *c)
63  {
64      g_assert(c->listen_channel);
65      g_io_channel_shutdown(c->listen_channel, true, NULL);
66      g_io_channel_unref(c->listen_channel);
67      c->listen_channel = NULL;
68  }
69  
70  /* cleanup state for closed connection/session, start accepting new
71   * connections if we're in listening mode
72   */
73  static void ga_channel_client_close(GAChannel *c)
74  {
75      g_assert(c->client_channel);
76      g_io_channel_shutdown(c->client_channel, true, NULL);
77      g_io_channel_unref(c->client_channel);
78      c->client_channel = NULL;
79      if (c->listen_channel) {
80          ga_channel_listen_add(c, 0, false);
81      }
82  }
83  
84  static gboolean ga_channel_client_event(GIOChannel *channel,
85                                          GIOCondition condition, gpointer data)
86  {
87      GAChannel *c = data;
88      gboolean client_cont;
89  
90      g_assert(c);
91      if (c->event_cb) {
92          client_cont = c->event_cb(condition, c->user_data);
93          if (!client_cont) {
94              ga_channel_client_close(c);
95              return false;
96          }
97      }
98      return true;
99  }
100  
101  static int ga_channel_client_add(GAChannel *c, int fd)
102  {
103      GIOChannel *client_channel;
104      GError *err = NULL;
105  
106      g_assert(c && !c->client_channel);
107      client_channel = g_io_channel_unix_new(fd);
108      g_assert(client_channel);
109      g_io_channel_set_encoding(client_channel, NULL, &err);
110      if (err != NULL) {
111          g_warning("error setting channel encoding to binary");
112          g_error_free(err);
113          return -1;
114      }
115      g_io_add_watch(client_channel, G_IO_IN | G_IO_HUP,
116                     ga_channel_client_event, c);
117      c->client_channel = client_channel;
118      return 0;
119  }
120  
121  static gboolean ga_channel_open(GAChannel *c, const gchar *path,
122                                  GAChannelMethod method, int fd)
123  {
124      int ret;
125      c->method = method;
126  
127      switch (c->method) {
128      case GA_CHANNEL_VIRTIO_SERIAL: {
129          assert(fd < 0);
130          fd = qemu_open_old(path, O_RDWR | O_NONBLOCK
131  #ifndef CONFIG_SOLARIS
132                             | O_ASYNC
133  #endif
134                             );
135          if (fd == -1) {
136              g_critical("error opening channel: %s", strerror(errno));
137              return false;
138          }
139  #ifdef CONFIG_SOLARIS
140          ret = ioctl(fd, I_SETSIG, S_OUTPUT | S_INPUT | S_HIPRI);
141          if (ret == -1) {
142              g_critical("error setting event mask for channel: %s",
143                         strerror(errno));
144              close(fd);
145              return false;
146          }
147  #endif
148          ret = ga_channel_client_add(c, fd);
149          if (ret) {
150              g_critical("error adding channel to main loop");
151              close(fd);
152              return false;
153          }
154          break;
155      }
156      case GA_CHANNEL_ISA_SERIAL: {
157          struct termios tio;
158  
159          assert(fd < 0);
160          fd = qemu_open_old(path, O_RDWR | O_NOCTTY | O_NONBLOCK);
161          if (fd == -1) {
162              g_critical("error opening channel: %s", strerror(errno));
163              return false;
164          }
165          tcgetattr(fd, &tio);
166          /* set up serial port for non-canonical, dumb byte streaming */
167          tio.c_iflag &= ~(IGNBRK | BRKINT | IGNPAR | PARMRK | INPCK | ISTRIP |
168                           INLCR | IGNCR | ICRNL | IXON | IXOFF | IXANY |
169                           IMAXBEL);
170          tio.c_oflag = 0;
171          tio.c_lflag = 0;
172          tio.c_cflag |= GA_CHANNEL_BAUDRATE_DEFAULT;
173          /* 1 available byte min or reads will block (we'll set non-blocking
174           * elsewhere, else we have to deal with read()=0 instead)
175           */
176          tio.c_cc[VMIN] = 1;
177          tio.c_cc[VTIME] = 0;
178          /* flush everything waiting for read/xmit, it's garbage at this point */
179          tcflush(fd, TCIFLUSH);
180          tcsetattr(fd, TCSANOW, &tio);
181          ret = ga_channel_client_add(c, fd);
182          if (ret) {
183              g_critical("error adding channel to main loop");
184              close(fd);
185              return false;
186          }
187          break;
188      }
189      case GA_CHANNEL_UNIX_LISTEN: {
190          if (fd < 0) {
191              Error *local_err = NULL;
192  
193              fd = unix_listen(path, &local_err);
194              if (local_err != NULL) {
195                  g_critical("%s", error_get_pretty(local_err));
196                  error_free(local_err);
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              Error *local_err = NULL;
206              SocketAddress *addr;
207              char *addr_str;
208  
209              addr_str = g_strdup_printf("vsock:%s", path);
210              addr = socket_parse(addr_str, &local_err);
211              g_free(addr_str);
212              if (local_err != NULL) {
213                  g_critical("%s", error_get_pretty(local_err));
214                  error_free(local_err);
215                  return false;
216              }
217  
218              fd = socket_listen(addr, 1, &local_err);
219              qapi_free_SocketAddress(addr);
220              if (local_err != NULL) {
221                  g_critical("%s", error_get_pretty(local_err));
222                  error_free(local_err);
223                  return false;
224              }
225          }
226          ga_channel_listen_add(c, fd, true);
227          break;
228      }
229      default:
230          g_critical("error binding/listening to specified socket");
231          return false;
232      }
233  
234      return true;
235  }
236  
237  GIOStatus ga_channel_write_all(GAChannel *c, const gchar *buf, gsize size)
238  {
239      GError *err = NULL;
240      gsize written = 0;
241      GIOStatus status = G_IO_STATUS_NORMAL;
242  
243      while (size) {
244          g_debug("sending data, count: %d", (int)size);
245          status = g_io_channel_write_chars(c->client_channel, buf, size,
246                                            &written, &err);
247          if (status == G_IO_STATUS_NORMAL) {
248              size -= written;
249              buf += written;
250          } else if (status != G_IO_STATUS_AGAIN) {
251              g_warning("error writing to channel: %s", err->message);
252              return status;
253          }
254      }
255  
256      do {
257          status = g_io_channel_flush(c->client_channel, &err);
258      } while (status == G_IO_STATUS_AGAIN);
259  
260      if (status != G_IO_STATUS_NORMAL) {
261          g_warning("error flushing channel: %s", err->message);
262      }
263  
264      return status;
265  }
266  
267  GIOStatus ga_channel_read(GAChannel *c, gchar *buf, gsize size, gsize *count)
268  {
269      return g_io_channel_read_chars(c->client_channel, buf, size, count, NULL);
270  }
271  
272  GAChannel *ga_channel_new(GAChannelMethod method, const gchar *path,
273                            int listen_fd, GAChannelCallback cb, gpointer opaque)
274  {
275      GAChannel *c = g_new0(GAChannel, 1);
276      c->event_cb = cb;
277      c->user_data = opaque;
278  
279      if (!ga_channel_open(c, path, method, listen_fd)) {
280          g_critical("error opening channel");
281          ga_channel_free(c);
282          return NULL;
283      }
284  
285      return c;
286  }
287  
288  void ga_channel_free(GAChannel *c)
289  {
290      if (c->listen_channel) {
291          ga_channel_listen_close(c);
292      }
293      if (c->client_channel) {
294          ga_channel_client_close(c);
295      }
296      g_free(c);
297  }
298