void *privdata; /* for client to remember who they are */
};
+typedef enum { HT_INPUT, HT_OUTPUT, HT_FOREIGN } HandleType;
+
/* ----------------------------------------------------------------------
* Input threads.
*/
*/
char buffer[4096]; /* the data read from the handle */
DWORD len; /* how much data that was */
- int readret; /* lets us know about read errors */
+ int readerr; /* lets us know about read errors */
/*
* Callback function called by this module when data arrives on
struct handle_input *ctx = (struct handle_input *) param;
OVERLAPPED ovl, *povl;
HANDLE oev;
- int readlen;
+ int readret, readlen, finished;
if (ctx->flags & HANDLE_FLAG_OVERLAPPED) {
povl = &ovl;
memset(povl, 0, sizeof(OVERLAPPED));
povl->hEvent = oev;
}
- ctx->readret = ReadFile(ctx->h, ctx->buffer, readlen,
- &ctx->len, povl);
- if (!ctx->readret)
- error = GetLastError();
- if (povl && !ctx->readret && error == ERROR_IO_PENDING) {
+ readret = ReadFile(ctx->h, ctx->buffer,readlen, &ctx->len, povl);
+ if (!readret)
+ ctx->readerr = GetLastError();
+ else
+ ctx->readerr = 0;
+ if (povl && !readret && ctx->readerr == ERROR_IO_PENDING) {
WaitForSingleObject(povl->hEvent, INFINITE);
- ctx->readret = GetOverlappedResult(ctx->h, povl, &ctx->len, FALSE);
+ readret = GetOverlappedResult(ctx->h, povl, &ctx->len, FALSE);
+ if (!readret)
+ ctx->readerr = GetLastError();
+ else
+ ctx->readerr = 0;
}
- if (!ctx->readret) {
+ if (!readret) {
/*
* Windows apparently sends ERROR_BROKEN_PIPE when a
* pipe we're reading from is closed normally from the
* isn't a natural EOF, _nothing_ is. So if we get that
* particular error, we pretend it's EOF.
*/
- if (error == ERROR_BROKEN_PIPE)
- ctx->readret = 1;
+ if (ctx->readerr == ERROR_BROKEN_PIPE)
+ ctx->readerr = 0;
ctx->len = 0;
}
- if (ctx->readret && ctx->len == 0 &&
+ if (readret && ctx->len == 0 &&
(ctx->flags & HANDLE_FLAG_IGNOREEOF))
continue;
+ /*
+ * If we just set ctx->len to 0, that means the read operation
+ * has returned end-of-file. Telling that to the main thread
+ * will cause it to set its 'defunct' flag and dispose of the
+ * handle structure at the next opportunity, in which case we
+ * mustn't touch ctx at all after the SetEvent. (Hence we do
+ * even _this_ check before the SetEvent.)
+ */
+ finished = (ctx->len == 0);
+
SetEvent(ctx->ev_to_main);
- if (!ctx->len)
+ if (finished)
break;
WaitForSingleObject(ctx->ev_from_main, INFINITE);
- if (ctx->done)
- break; /* main thread told us to shut down */
+ if (ctx->done) {
+ /*
+ * The main thread has asked us to shut down. Send back an
+ * event indicating that we've done so. Hereafter we must
+ * not touch ctx at all, because the main thread might
+ * have freed it.
+ */
+ SetEvent(ctx->ev_to_main);
+ break;
+ }
}
if (povl)
* and read by the main thread after receiving that signal.
*/
DWORD lenwritten; /* how much data we actually wrote */
- int writeret; /* return value from WriteFile */
+ int writeerr; /* return value from WriteFile */
/*
* Data only ever read or written by the main thread.
*/
bufchain queued_data; /* data still waiting to be written */
+ enum { EOF_NO, EOF_PENDING, EOF_SENT } outgoingeof;
/*
* Callback function called when the backlog in the bufchain
{
struct handle_output *ctx = (struct handle_output *) param;
OVERLAPPED ovl, *povl;
+ HANDLE oev;
+ int writeret;
- if (ctx->flags & HANDLE_FLAG_OVERLAPPED)
+ if (ctx->flags & HANDLE_FLAG_OVERLAPPED) {
povl = &ovl;
- else
+ oev = CreateEvent(NULL, TRUE, FALSE, NULL);
+ } else {
povl = NULL;
+ }
while (1) {
WaitForSingleObject(ctx->ev_from_main, INFINITE);
if (ctx->done) {
+ /*
+ * The main thread has asked us to shut down. Send back an
+ * event indicating that we've done so. Hereafter we must
+ * not touch ctx at all, because the main thread might
+ * have freed it.
+ */
SetEvent(ctx->ev_to_main);
break;
}
- if (povl)
+ if (povl) {
memset(povl, 0, sizeof(OVERLAPPED));
- ctx->writeret = WriteFile(ctx->h, ctx->buffer, ctx->len,
- &ctx->lenwritten, povl);
- if (povl && !ctx->writeret && GetLastError() == ERROR_IO_PENDING)
- ctx->writeret = GetOverlappedResult(ctx->h, povl,
- &ctx->lenwritten, TRUE);
+ povl->hEvent = oev;
+ }
+
+ writeret = WriteFile(ctx->h, ctx->buffer, ctx->len,
+ &ctx->lenwritten, povl);
+ if (!writeret)
+ ctx->writeerr = GetLastError();
+ else
+ ctx->writeerr = 0;
+ if (povl && !writeret && GetLastError() == ERROR_IO_PENDING) {
+ writeret = GetOverlappedResult(ctx->h, povl,
+ &ctx->lenwritten, TRUE);
+ if (!writeret)
+ ctx->writeerr = GetLastError();
+ else
+ ctx->writeerr = 0;
+ }
SetEvent(ctx->ev_to_main);
- if (!ctx->writeret)
+ if (!writeret) {
+ /*
+ * The write operation has suffered an error. Telling that
+ * to the main thread will cause it to set its 'defunct'
+ * flag and dispose of the handle structure at the next
+ * opportunity, so we must not touch ctx at all after
+ * this.
+ */
break;
+ }
}
+ if (povl)
+ CloseHandle(oev);
+
return 0;
}
ctx->len = sendlen;
SetEvent(ctx->ev_from_main);
ctx->busy = TRUE;
+ } else if (!ctx->busy && bufchain_size(&ctx->queued_data) == 0 &&
+ ctx->outgoingeof == EOF_PENDING) {
+ CloseHandle(ctx->h);
+ ctx->h = INVALID_HANDLE_VALUE;
+ ctx->outgoingeof = EOF_SENT;
}
}
+/* ----------------------------------------------------------------------
+ * 'Foreign events'. These are handle structures which just contain a
+ * single event object passed to us by another module such as
+ * winnps.c, so that they can make use of our handle_get_events /
+ * handle_got_event mechanism for communicating with application main
+ * loops.
+ */
+struct handle_foreign {
+ /*
+ * Copy of the handle_generic structure.
+ */
+ HANDLE h; /* the handle itself */
+ HANDLE ev_to_main; /* event used to signal main thread */
+ HANDLE ev_from_main; /* event used to signal back to us */
+ int moribund; /* are we going to kill this soon? */
+ int done; /* request subthread to terminate */
+ int defunct; /* has the subthread already gone? */
+ int busy; /* operation currently in progress? */
+ void *privdata; /* for client to remember who they are */
+
+ /*
+ * Our own data, just consisting of knowledge of who to call back.
+ */
+ void (*callback)(void *);
+ void *ctx;
+};
+
/* ----------------------------------------------------------------------
* Unified code handling both input and output threads.
*/
struct handle {
- int output;
+ HandleType type;
union {
struct handle_generic g;
struct handle_input i;
struct handle_output o;
+ struct handle_foreign f;
} u;
};
struct handle *a = (struct handle *)av;
struct handle *b = (struct handle *)bv;
- if ((unsigned)a->u.g.ev_to_main < (unsigned)b->u.g.ev_to_main)
+ if ((uintptr_t)a->u.g.ev_to_main < (uintptr_t)b->u.g.ev_to_main)
return -1;
- else if ((unsigned)a->u.g.ev_to_main > (unsigned)b->u.g.ev_to_main)
+ else if ((uintptr_t)a->u.g.ev_to_main > (uintptr_t)b->u.g.ev_to_main)
return +1;
else
return 0;
HANDLE *a = (HANDLE *)av;
struct handle *b = (struct handle *)bv;
- if ((unsigned)*a < (unsigned)b->u.g.ev_to_main)
+ if ((uintptr_t)*a < (uintptr_t)b->u.g.ev_to_main)
return -1;
- else if ((unsigned)*a > (unsigned)b->u.g.ev_to_main)
+ else if ((uintptr_t)*a > (uintptr_t)b->u.g.ev_to_main)
return +1;
else
return 0;
struct handle *h = snew(struct handle);
DWORD in_threadid; /* required for Win9x */
- h->output = FALSE;
+ h->type = HT_INPUT;
h->u.i.h = handle;
h->u.i.ev_to_main = CreateEvent(NULL, FALSE, FALSE, NULL);
h->u.i.ev_from_main = CreateEvent(NULL, FALSE, FALSE, NULL);
struct handle *h = snew(struct handle);
DWORD out_threadid; /* required for Win9x */
- h->output = TRUE;
+ h->type = HT_OUTPUT;
h->u.o.h = handle;
h->u.o.ev_to_main = CreateEvent(NULL, FALSE, FALSE, NULL);
h->u.o.ev_from_main = CreateEvent(NULL, FALSE, FALSE, NULL);
h->u.o.done = FALSE;
h->u.o.privdata = privdata;
bufchain_init(&h->u.o.queued_data);
+ h->u.o.outgoingeof = EOF_NO;
h->u.o.sentdata = sentdata;
h->u.o.flags = flags;
add234(handles_by_evtomain, h);
CreateThread(NULL, 0, handle_output_threadfunc,
- &h->u.i, 0, &out_threadid);
+ &h->u.o, 0, &out_threadid);
+
+ return h;
+}
+
+struct handle *handle_add_foreign_event(HANDLE event,
+ void (*callback)(void *), void *ctx)
+{
+ struct handle *h = snew(struct handle);
+
+ h->type = HT_FOREIGN;
+ h->u.f.h = INVALID_HANDLE_VALUE;
+ h->u.f.ev_to_main = event;
+ h->u.f.ev_from_main = INVALID_HANDLE_VALUE;
+ h->u.f.defunct = TRUE; /* we have no thread in the first place */
+ h->u.f.moribund = FALSE;
+ h->u.f.done = FALSE;
+ h->u.f.privdata = NULL;
+ h->u.f.callback = callback;
+ h->u.f.ctx = ctx;
+ h->u.f.busy = TRUE;
+
+ if (!handles_by_evtomain)
+ handles_by_evtomain = newtree234(handle_cmp_evtomain);
+ add234(handles_by_evtomain, h);
return h;
}
int handle_write(struct handle *h, const void *data, int len)
{
- assert(h->output);
+ assert(h->type == HT_OUTPUT);
+ assert(h->u.o.outgoingeof == EOF_NO);
bufchain_add(&h->u.o.queued_data, data, len);
handle_try_output(&h->u.o);
return bufchain_size(&h->u.o.queued_data);
}
+void handle_write_eof(struct handle *h)
+{
+ /*
+ * This function is called when we want to proactively send an
+ * end-of-file notification on the handle. We can only do this by
+ * actually closing the handle - so never call this on a
+ * bidirectional handle if we're still interested in its incoming
+ * direction!
+ */
+ assert(h->type == HT_OUTPUT);
+ if (h->u.o.outgoingeof == EOF_NO) {
+ h->u.o.outgoingeof = EOF_PENDING;
+ handle_try_output(&h->u.o);
+ }
+}
+
HANDLE *handle_get_events(int *nevents)
{
HANDLE *ret;
static void handle_destroy(struct handle *h)
{
- if (h->output)
+ if (h->type == HT_OUTPUT)
bufchain_clear(&h->u.o.queued_data);
CloseHandle(h->u.g.ev_from_main);
CloseHandle(h->u.g.ev_to_main);
void handle_free(struct handle *h)
{
- /*
- * If the handle is currently busy, we cannot immediately free
- * it. Instead we must wait until it's finished its current
- * operation, because otherwise the subthread will write to
- * invalid memory after we free its context from under it.
- */
assert(h && !h->u.g.moribund);
- if (h->u.g.busy) {
- /*
- * Just set the moribund flag, which will be noticed next
- * time an operation completes.
+ if (h->u.g.busy && h->type != HT_FOREIGN) {
+ /*
+ * If the handle is currently busy, we cannot immediately free
+ * it, because its subthread is in the middle of something.
+ * (Exception: foreign handles don't have a subthread.)
+ *
+ * Instead we must wait until it's finished its current
+ * operation, because otherwise the subthread will write to
+ * invalid memory after we free its context from under it. So
+ * we set the moribund flag, which will be noticed next time
+ * an operation completes.
*/
h->u.g.moribund = TRUE;
} else if (h->u.g.defunct) {
if (h->u.g.moribund) {
/*
- * A moribund handle is already treated as dead from the
- * external user's point of view, so do nothing with the
- * actual event. Just signal the thread to die if
- * necessary, or destroy the handle if not.
+ * A moribund handle is one which we have either already
+ * signalled to die, or are waiting until its current I/O op
+ * completes to do so. Either way, it's treated as already
+ * dead from the external user's point of view, so we ignore
+ * the actual I/O result. We just signal the thread to die if
+ * we haven't yet done so, or destroy the handle if not.
*/
if (h->u.g.done) {
handle_destroy(h);
return;
}
- if (!h->output) {
+ switch (h->type) {
int backlog;
+ case HT_INPUT:
h->u.i.busy = FALSE;
/*
/*
* EOF, or (nearly equivalently) read error.
*/
- h->u.i.gotdata(h, NULL, (h->u.i.readret ? 0 : -1));
h->u.i.defunct = TRUE;
+ h->u.i.gotdata(h, NULL, -h->u.i.readerr);
} else {
backlog = h->u.i.gotdata(h, h->u.i.buffer, h->u.i.len);
handle_throttle(&h->u.i, backlog);
}
- } else {
+ break;
+
+ case HT_OUTPUT:
h->u.o.busy = FALSE;
/*
* write. Call the callback to indicate that the output
* buffer size has decreased, or to indicate an error.
*/
- if (!h->u.o.writeret) {
+ if (h->u.o.writeerr) {
/*
* Write error. Send a negative value to the callback,
* and mark the thread as defunct (because the output
* thread is terminating by now).
*/
- h->u.o.sentdata(h, -1);
h->u.o.defunct = TRUE;
+ h->u.o.sentdata(h, -h->u.o.writeerr);
} else {
bufchain_consume(&h->u.o.queued_data, h->u.o.lenwritten);
h->u.o.sentdata(h, bufchain_size(&h->u.o.queued_data));
handle_try_output(&h->u.o);
}
+ break;
+
+ case HT_FOREIGN:
+ /* Just call the callback. */
+ h->u.f.callback(h->u.f.ctx);
+ break;
}
}
void handle_unthrottle(struct handle *h, int backlog)
{
- assert(!h->output);
+ assert(h->type == HT_INPUT);
handle_throttle(&h->u.i, backlog);
}
int handle_backlog(struct handle *h)
{
- assert(h->output);
+ assert(h->type == HT_OUTPUT);
return bufchain_size(&h->u.o.queued_data);
}
projects / PuTTY.git / blobdiff