8 #include "qga/guest-agent-core.h"
9 #include "qga/channel.h"
11 typedef struct GAChannelReadState {
15 size_t cur; /* current buffer start */
16 size_t pending; /* pending buffered bytes to read */
18 bool ov_pending; /* whether on async read is outstanding */
25 GAChannelReadState rstate;
26 GIOCondition pending_events; /* TODO: use GAWatch.pollfd.revents */
30 typedef struct GAWatch {
34 GIOCondition events_mask;
38 * Called by glib prior to polling to set up poll events if polling is needed.
41 static gboolean ga_channel_prepare(GSource *source, gint *timeout_ms)
43 GAWatch *watch = (GAWatch *)source;
44 GAChannel *c = (GAChannel *)watch->channel;
45 GAChannelReadState *rs = &c->rstate;
46 DWORD count_read, count_to_read = 0;
48 GIOCondition new_events = 0;
51 /* go ahead and submit another read if there's room in the buffer
52 * and no previous reads are outstanding
54 if (!rs->ov_pending) {
55 if (rs->cur + rs->pending >= rs->buf_size) {
57 memmove(rs->buf, rs->buf + rs->cur, rs->pending);
61 count_to_read = rs->buf_size - rs->cur - rs->pending;
64 if (rs->ov_pending || count_to_read <= 0) {
69 success = ReadFile(c->handle, rs->buf + rs->cur + rs->pending,
70 count_to_read, &count_read, &rs->ov);
72 rs->pending += count_read;
73 rs->ov_pending = false;
75 if (GetLastError() == ERROR_IO_PENDING) {
76 rs->ov_pending = true;
78 new_events |= G_IO_ERR;
83 /* dont block forever, iterate the main loop every once and a while */
85 /* if there's data in the read buffer, or another event is pending,
86 * skip polling and issue user cb.
89 new_events |= G_IO_IN;
91 c->pending_events |= new_events;
92 return !!c->pending_events;
96 * Called by glib after an outstanding read request is completed.
98 static gboolean ga_channel_check(GSource *source)
100 GAWatch *watch = (GAWatch *)source;
101 GAChannel *c = (GAChannel *)watch->channel;
102 GAChannelReadState *rs = &c->rstate;
103 DWORD count_read, error;
106 GIOCondition new_events = 0;
110 /* failing this implies we issued a read that completed immediately,
111 * yet no data was placed into the buffer (and thus we did not skip
112 * polling). but since EOF is not obtainable until we retrieve an
113 * overlapped result, it must be the case that there was data placed
114 * into the buffer, or an error was generated by Readfile(). in either
115 * case, we should've skipped the polling for this round.
117 g_assert(rs->ov_pending);
119 success = GetOverlappedResult(c->handle, &rs->ov, &count_read, FALSE);
121 g_debug("thread: overlapped result, count_read: %d", (int)count_read);
122 rs->pending += count_read;
123 new_events |= G_IO_IN;
125 error = GetLastError();
126 if (error == 0 || error == ERROR_HANDLE_EOF ||
127 error == ERROR_NO_SYSTEM_RESOURCES ||
128 error == ERROR_OPERATION_ABORTED) {
129 /* note: On WinXP SP3 with rhel6ga virtio-win-1.1.16 vioser drivers,
130 * ENSR seems to be synonymous with when we'd normally expect
131 * ERROR_HANDLE_EOF. So treat it as such. Microsoft's
132 * recommendation for ERROR_NO_SYSTEM_RESOURCES is to
133 * retry the read, so this happens to work out anyway. On newer
134 * virtio-win driver, this seems to be replaced with EOA, so
135 * handle that in the same fashion.
137 new_events |= G_IO_HUP;
138 } else if (error != ERROR_IO_INCOMPLETE) {
139 g_critical("error retrieving overlapped result: %d", (int)error);
140 new_events |= G_IO_ERR;
147 c->pending_events |= new_events;
149 return !!c->pending_events;
153 * Called by glib after either prepare or check routines signal readiness
155 static gboolean ga_channel_dispatch(GSource *source, GSourceFunc unused,
158 GAWatch *watch = (GAWatch *)source;
159 GAChannel *c = (GAChannel *)watch->channel;
160 GAChannelReadState *rs = &c->rstate;
164 success = c->cb(watch->pollfd.revents, c->user_data);
166 if (c->pending_events & G_IO_ERR) {
167 g_critical("channel error, removing source");
171 /* TODO: replace rs->pending with watch->revents */
172 c->pending_events &= ~G_IO_HUP;
174 c->pending_events &= ~G_IO_IN;
176 c->pending_events = 0;
181 static void ga_channel_finalize(GSource *source)
186 GSourceFuncs ga_channel_watch_funcs = {
193 static GSource *ga_channel_create_watch(GAChannel *c)
195 GSource *source = g_source_new(&ga_channel_watch_funcs, sizeof(GAWatch));
196 GAWatch *watch = (GAWatch *)source;
199 watch->pollfd.fd = (gintptr) c->rstate.ov.hEvent;
200 g_source_add_poll(source, &watch->pollfd);
205 GIOStatus ga_channel_read(GAChannel *c, char *buf, size_t size, gsize *count)
207 GAChannelReadState *rs = &c->rstate;
211 if (c->pending_events & G_IO_ERR) {
212 return G_IO_STATUS_ERROR;
215 *count = to_read = MIN(size, rs->pending);
217 memcpy(buf, rs->buf + rs->cur, to_read);
219 rs->pending -= to_read;
220 status = G_IO_STATUS_NORMAL;
222 status = G_IO_STATUS_AGAIN;
228 static GIOStatus ga_channel_write(GAChannel *c, const char *buf, size_t size,
236 ov.hEvent = CreateEvent(NULL, FALSE, FALSE, NULL);
237 ret = WriteFile(c->handle, buf, size, &written, &ov);
239 if (GetLastError() == ERROR_IO_PENDING) {
240 /* write is pending */
241 ret = GetOverlappedResult(c->handle, &ov, &written, TRUE);
243 if (!GetLastError()) {
244 status = G_IO_STATUS_AGAIN;
246 status = G_IO_STATUS_ERROR;
249 /* write is complete */
250 status = G_IO_STATUS_NORMAL;
254 status = G_IO_STATUS_ERROR;
257 /* write returned immediately */
258 status = G_IO_STATUS_NORMAL;
263 CloseHandle(ov.hEvent);
269 GIOStatus ga_channel_write_all(GAChannel *c, const char *buf, size_t size)
271 GIOStatus status = G_IO_STATUS_NORMAL;
275 status = ga_channel_write(c, buf, size, &count);
276 if (status == G_IO_STATUS_NORMAL) {
279 } else if (status != G_IO_STATUS_AGAIN) {
287 static gboolean ga_channel_open(GAChannel *c, GAChannelMethod method,
290 COMMTIMEOUTS comTimeOut = {0};
291 gchar newpath[MAXPATHLEN] = {0};
292 comTimeOut.ReadIntervalTimeout = 1;
294 if (method != GA_CHANNEL_VIRTIO_SERIAL && method != GA_CHANNEL_ISA_SERIAL) {
295 g_critical("unsupported communication method");
299 if (method == GA_CHANNEL_ISA_SERIAL){
300 snprintf(newpath, sizeof(newpath), "\\\\.\\%s", path);
302 g_strlcpy(newpath, path, sizeof(newpath));
305 c->handle = CreateFile(newpath, GENERIC_READ | GENERIC_WRITE, 0, NULL,
307 FILE_FLAG_NO_BUFFERING | FILE_FLAG_OVERLAPPED, NULL);
308 if (c->handle == INVALID_HANDLE_VALUE) {
309 g_critical("error opening path %s", newpath);
313 if (method == GA_CHANNEL_ISA_SERIAL && !SetCommTimeouts(c->handle,&comTimeOut)) {
314 g_critical("error setting timeout for com port: %lu",GetLastError());
315 CloseHandle(c->handle);
322 GAChannel *ga_channel_new(GAChannelMethod method, const gchar *path,
323 GAChannelCallback cb, gpointer opaque)
325 GAChannel *c = g_new0(GAChannel, 1);
326 SECURITY_ATTRIBUTES sec_attrs;
328 if (!ga_channel_open(c, method, path)) {
329 g_critical("error opening channel");
335 c->user_data = opaque;
337 sec_attrs.nLength = sizeof(SECURITY_ATTRIBUTES);
338 sec_attrs.lpSecurityDescriptor = NULL;
339 sec_attrs.bInheritHandle = false;
341 c->rstate.buf_size = QGA_READ_COUNT_DEFAULT;
342 c->rstate.buf = g_malloc(QGA_READ_COUNT_DEFAULT);
343 c->rstate.ov.hEvent = CreateEvent(&sec_attrs, FALSE, FALSE, NULL);
345 c->source = ga_channel_create_watch(c);
346 g_source_attach(c->source, NULL);
350 void ga_channel_free(GAChannel *c)
353 g_source_destroy(c->source);
355 if (c->rstate.ov.hEvent) {
356 CloseHandle(c->rstate.ov.hEvent);
358 g_free(c->rstate.buf);