xref: /openbmc/qemu/qga/channel-posix.c (revision 1fd6bb44)
1 #include <glib.h>
2 #include <termios.h>
3 #include <errno.h>
4 #include <unistd.h>
5 #include <fcntl.h>
6 #include <stdlib.h>
7 #include <string.h>
8 #include "qemu/osdep.h"
9 #include "qemu/sockets.h"
10 #include "qga/channel.h"
11 
12 #ifdef CONFIG_SOLARIS
13 #include <stropts.h>
14 #endif
15 
16 #define GA_CHANNEL_BAUDRATE_DEFAULT B38400 /* for isa-serial channels */
17 
18 struct GAChannel {
19     GIOChannel *listen_channel;
20     GIOChannel *client_channel;
21     GAChannelMethod method;
22     GAChannelCallback event_cb;
23     gpointer user_data;
24 };
25 
26 static int ga_channel_client_add(GAChannel *c, int fd);
27 
28 static gboolean ga_channel_listen_accept(GIOChannel *channel,
29                                          GIOCondition condition, gpointer data)
30 {
31     GAChannel *c = data;
32     int ret, client_fd;
33     bool accepted = false;
34     struct sockaddr_un addr;
35     socklen_t addrlen = sizeof(addr);
36 
37     g_assert(channel != NULL);
38 
39     client_fd = qemu_accept(g_io_channel_unix_get_fd(channel),
40                             (struct sockaddr *)&addr, &addrlen);
41     if (client_fd == -1) {
42         g_warning("error converting fd to gsocket: %s", strerror(errno));
43         goto out;
44     }
45     fcntl(client_fd, F_SETFL, O_NONBLOCK);
46     ret = ga_channel_client_add(c, client_fd);
47     if (ret) {
48         g_warning("error setting up connection");
49         close(client_fd);
50         goto out;
51     }
52     accepted = true;
53 
54 out:
55     /* only accept 1 connection at a time */
56     return !accepted;
57 }
58 
59 /* start polling for readable events on listen fd, new==true
60  * indicates we should use the existing s->listen_channel
61  */
62 static void ga_channel_listen_add(GAChannel *c, int listen_fd, bool create)
63 {
64     if (create) {
65         c->listen_channel = g_io_channel_unix_new(listen_fd);
66     }
67     g_io_add_watch(c->listen_channel, G_IO_IN, ga_channel_listen_accept, c);
68 }
69 
70 static void ga_channel_listen_close(GAChannel *c)
71 {
72     g_assert(c->method == GA_CHANNEL_UNIX_LISTEN);
73     g_assert(c->listen_channel);
74     g_io_channel_shutdown(c->listen_channel, true, NULL);
75     g_io_channel_unref(c->listen_channel);
76     c->listen_channel = NULL;
77 }
78 
79 /* cleanup state for closed connection/session, start accepting new
80  * connections if we're in listening mode
81  */
82 static void ga_channel_client_close(GAChannel *c)
83 {
84     g_assert(c->client_channel);
85     g_io_channel_shutdown(c->client_channel, true, NULL);
86     g_io_channel_unref(c->client_channel);
87     c->client_channel = NULL;
88     if (c->method == GA_CHANNEL_UNIX_LISTEN && c->listen_channel) {
89         ga_channel_listen_add(c, 0, false);
90     }
91 }
92 
93 static gboolean ga_channel_client_event(GIOChannel *channel,
94                                         GIOCondition condition, gpointer data)
95 {
96     GAChannel *c = data;
97     gboolean client_cont;
98 
99     g_assert(c);
100     if (c->event_cb) {
101         client_cont = c->event_cb(condition, c->user_data);
102         if (!client_cont) {
103             ga_channel_client_close(c);
104             return false;
105         }
106     }
107     return true;
108 }
109 
110 static int ga_channel_client_add(GAChannel *c, int fd)
111 {
112     GIOChannel *client_channel;
113     GError *err = NULL;
114 
115     g_assert(c && !c->client_channel);
116     client_channel = g_io_channel_unix_new(fd);
117     g_assert(client_channel);
118     g_io_channel_set_encoding(client_channel, NULL, &err);
119     if (err != NULL) {
120         g_warning("error setting channel encoding to binary");
121         g_error_free(err);
122         return -1;
123     }
124     g_io_add_watch(client_channel, G_IO_IN | G_IO_HUP,
125                    ga_channel_client_event, c);
126     c->client_channel = client_channel;
127     return 0;
128 }
129 
130 static gboolean ga_channel_open(GAChannel *c, const gchar *path, GAChannelMethod method)
131 {
132     int ret;
133     c->method = method;
134 
135     switch (c->method) {
136     case GA_CHANNEL_VIRTIO_SERIAL: {
137         int fd = qemu_open(path, O_RDWR | O_NONBLOCK
138 #ifndef CONFIG_SOLARIS
139                            | O_ASYNC
140 #endif
141                            );
142         if (fd == -1) {
143             g_critical("error opening channel: %s", strerror(errno));
144             return false;
145         }
146 #ifdef CONFIG_SOLARIS
147         ret = ioctl(fd, I_SETSIG, S_OUTPUT | S_INPUT | S_HIPRI);
148         if (ret == -1) {
149             g_critical("error setting event mask for channel: %s",
150                        strerror(errno));
151             close(fd);
152             return false;
153         }
154 #endif
155         ret = ga_channel_client_add(c, fd);
156         if (ret) {
157             g_critical("error adding channel to main loop");
158             close(fd);
159             return false;
160         }
161         break;
162     }
163     case GA_CHANNEL_ISA_SERIAL: {
164         struct termios tio;
165         int fd = qemu_open(path, O_RDWR | O_NOCTTY | O_NONBLOCK);
166         if (fd == -1) {
167             g_critical("error opening channel: %s", strerror(errno));
168             return false;
169         }
170         tcgetattr(fd, &tio);
171         /* set up serial port for non-canonical, dumb byte streaming */
172         tio.c_iflag &= ~(IGNBRK | BRKINT | IGNPAR | PARMRK | INPCK | ISTRIP |
173                          INLCR | IGNCR | ICRNL | IXON | IXOFF | IXANY |
174                          IMAXBEL);
175         tio.c_oflag = 0;
176         tio.c_lflag = 0;
177         tio.c_cflag |= GA_CHANNEL_BAUDRATE_DEFAULT;
178         /* 1 available byte min or reads will block (we'll set non-blocking
179          * elsewhere, else we have to deal with read()=0 instead)
180          */
181         tio.c_cc[VMIN] = 1;
182         tio.c_cc[VTIME] = 0;
183         /* flush everything waiting for read/xmit, it's garbage at this point */
184         tcflush(fd, TCIFLUSH);
185         tcsetattr(fd, TCSANOW, &tio);
186         ret = ga_channel_client_add(c, fd);
187         if (ret) {
188             g_critical("error adding channel to main loop");
189             close(fd);
190             return false;
191         }
192         break;
193     }
194     case GA_CHANNEL_UNIX_LISTEN: {
195         Error *local_err = NULL;
196         int fd = unix_listen(path, NULL, strlen(path), &local_err);
197         if (local_err != NULL) {
198             g_critical("%s", error_get_pretty(local_err));
199             error_free(local_err);
200             return false;
201         }
202         ga_channel_listen_add(c, fd, true);
203         break;
204     }
205     default:
206         g_critical("error binding/listening to specified socket");
207         return false;
208     }
209 
210     return true;
211 }
212 
213 GIOStatus ga_channel_write_all(GAChannel *c, const gchar *buf, gsize size)
214 {
215     GError *err = NULL;
216     gsize written = 0;
217     GIOStatus status = G_IO_STATUS_NORMAL;
218 
219     while (size) {
220         status = g_io_channel_write_chars(c->client_channel, buf, size,
221                                           &written, &err);
222         g_debug("sending data, count: %d", (int)size);
223         if (err != NULL) {
224             g_warning("error writing to channel: %s", err->message);
225             return G_IO_STATUS_ERROR;
226         }
227         if (status != G_IO_STATUS_NORMAL) {
228             break;
229         }
230         size -= written;
231     }
232 
233     if (status == G_IO_STATUS_NORMAL) {
234         status = g_io_channel_flush(c->client_channel, &err);
235         if (err != NULL) {
236             g_warning("error flushing channel: %s", err->message);
237             return G_IO_STATUS_ERROR;
238         }
239     }
240 
241     return status;
242 }
243 
244 GIOStatus ga_channel_read(GAChannel *c, gchar *buf, gsize size, gsize *count)
245 {
246     return g_io_channel_read_chars(c->client_channel, buf, size, count, NULL);
247 }
248 
249 GAChannel *ga_channel_new(GAChannelMethod method, const gchar *path,
250                           GAChannelCallback cb, gpointer opaque)
251 {
252     GAChannel *c = g_malloc0(sizeof(GAChannel));
253     c->event_cb = cb;
254     c->user_data = opaque;
255 
256     if (!ga_channel_open(c, path, method)) {
257         g_critical("error opening channel");
258         ga_channel_free(c);
259         return NULL;
260     }
261 
262     return c;
263 }
264 
265 void ga_channel_free(GAChannel *c)
266 {
267     if (c->method == GA_CHANNEL_UNIX_LISTEN
268         && c->listen_channel) {
269         ga_channel_listen_close(c);
270     }
271     if (c->client_channel) {
272         ga_channel_client_close(c);
273     }
274     g_free(c);
275 }
276