* write; so the output thread waits for an event object notifying
* it to _attempt_ a write, and then it sets an event in return
* when one completes.
+ *
+ * (It's terribly annoying having to spawn a subthread for each
+ * direction of each handle. Technically it isn't necessary for
+ * serial ports, since we could use overlapped I/O within the main
+ * thread and wait directly on the event objects in the OVERLAPPED
+ * structures. However, we can't use this trick for some types of
+ * file handle at all - for some reason Windows restricts use of
+ * OVERLAPPED to files which were opened with the overlapped flag -
+ * and so we must use threads for those. This being the case, it's
+ * simplest just to use threads for everything rather than trying
+ * to keep track of multiple completely separate mechanisms.)
*/
#include <assert.h>
void *privdata; /* for client to remember who they are */
/*
+ * Data set at initialisation and then read-only.
+ */
+ int flags;
+
+ /*
* Data set by the input thread before signalling ev_to_main,
* and read by the main thread after receiving that signal.
*/
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
static DWORD WINAPI handle_input_threadfunc(void *param)
{
struct handle_input *ctx = (struct handle_input *) param;
+ OVERLAPPED ovl, *povl;
+ HANDLE oev;
+ int readret, readlen;
+
+ if (ctx->flags & HANDLE_FLAG_OVERLAPPED) {
+ povl = &ovl;
+ oev = CreateEvent(NULL, TRUE, FALSE, NULL);
+ } else {
+ povl = NULL;
+ }
+
+ if (ctx->flags & HANDLE_FLAG_UNITBUFFER)
+ readlen = 1;
+ else
+ readlen = sizeof(ctx->buffer);
while (1) {
- ctx->readret = ReadFile(ctx->h, ctx->buffer, sizeof(ctx->buffer),
- &ctx->len, NULL);
- if (!ctx->readret)
+ if (povl) {
+ memset(povl, 0, sizeof(OVERLAPPED));
+ povl->hEvent = oev;
+ }
+ 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);
+ readret = GetOverlappedResult(ctx->h, povl, &ctx->len, FALSE);
+ if (!readret)
+ ctx->readerr = GetLastError();
+ else
+ ctx->readerr = 0;
+ }
+
+ if (!readret) {
+ /*
+ * Windows apparently sends ERROR_BROKEN_PIPE when a
+ * pipe we're reading from is closed normally from the
+ * writing end. This is ludicrous; if that situation
+ * isn't a natural EOF, _nothing_ is. So if we get that
+ * particular error, we pretend it's EOF.
+ */
+ if (ctx->readerr == ERROR_BROKEN_PIPE)
+ ctx->readerr = 0;
ctx->len = 0;
+ }
+
+ if (readret && ctx->len == 0 &&
+ (ctx->flags & HANDLE_FLAG_IGNOREEOF))
+ continue;
SetEvent(ctx->ev_to_main);
break; /* main thread told us to shut down */
}
+ if (povl)
+ CloseHandle(oev);
+
return 0;
}
*/
static void handle_throttle(struct handle_input *ctx, int backlog)
{
- assert(!ctx->defunct);
+ if (ctx->defunct)
+ return;
/*
* If there's a read operation already in progress, do nothing:
void *privdata; /* for client to remember who they are */
/*
+ * Data set at initialisation and then read-only.
+ */
+ int flags;
+
+ /*
* Data set by the main thread before signalling ev_from_main,
* and read by the input thread after receiving that signal.
*/
* 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
static DWORD WINAPI handle_output_threadfunc(void *param)
{
struct handle_output *ctx = (struct handle_output *) param;
+ OVERLAPPED ovl, *povl;
+ HANDLE oev;
+ int writeret;
+
+ if (ctx->flags & HANDLE_FLAG_OVERLAPPED) {
+ povl = &ovl;
+ oev = CreateEvent(NULL, TRUE, FALSE, NULL);
+ } else {
+ povl = NULL;
+ }
while (1) {
WaitForSingleObject(ctx->ev_from_main, INFINITE);
SetEvent(ctx->ev_to_main);
break;
}
- ctx->writeret = WriteFile(ctx->h, ctx->buffer, ctx->len,
- &ctx->lenwritten, NULL);
+ if (povl) {
+ memset(povl, 0, sizeof(OVERLAPPED));
+ 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)
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;
}
}
}
struct handle *handle_input_new(HANDLE handle, handle_inputfn_t gotdata,
- void *privdata)
+ void *privdata, int flags)
{
struct handle *h = snew(struct handle);
+ DWORD in_threadid; /* required for Win9x */
h->output = FALSE;
h->u.i.h = handle;
h->u.i.moribund = FALSE;
h->u.i.done = FALSE;
h->u.i.privdata = privdata;
+ h->u.i.flags = flags;
if (!handles_by_evtomain)
handles_by_evtomain = newtree234(handle_cmp_evtomain);
add234(handles_by_evtomain, h);
CreateThread(NULL, 0, handle_input_threadfunc,
- &h->u.i, 0, NULL);
+ &h->u.i, 0, &in_threadid);
h->u.i.busy = TRUE;
return h;
}
struct handle *handle_output_new(HANDLE handle, handle_outputfn_t sentdata,
- void *privdata)
+ void *privdata, int flags)
{
struct handle *h = snew(struct handle);
+ DWORD out_threadid; /* required for Win9x */
h->output = TRUE;
h->u.o.h = handle;
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;
if (!handles_by_evtomain)
handles_by_evtomain = newtree234(handle_cmp_evtomain);
add234(handles_by_evtomain, h);
CreateThread(NULL, 0, handle_output_threadfunc,
- &h->u.i, 0, NULL);
+ &h->u.o, 0, &out_threadid);
return h;
}
int handle_write(struct handle *h, const void *data, int len)
{
assert(h->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->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;
*/
h->u.g.moribund = TRUE;
h->u.g.done = TRUE;
+ h->u.g.busy = TRUE;
SetEvent(h->u.g.ev_from_main);
}
}
handle_destroy(h);
} else {
h->u.g.done = TRUE;
+ h->u.g.busy = TRUE;
SetEvent(h->u.g.ev_from_main);
}
return;
/*
* EOF, or (nearly equivalently) read error.
*/
- h->u.i.gotdata(h, NULL, (h->u.i.readret ? 0 : -1));
+ h->u.i.gotdata(h, NULL, -h->u.i.readerr);
h->u.i.defunct = TRUE;
} else {
backlog = h->u.i.gotdata(h, h->u.i.buffer, h->u.i.len);
* 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.sentdata(h, -h->u.o.writeerr);
h->u.o.defunct = TRUE;
} else {
bufchain_consume(&h->u.o.queued_data, h->u.o.lenwritten);
~mdw / sgt / putty / blobdiff