X-Git-Url: https://git.distorted.org.uk/u/mdw/putty/blobdiff_plain/0e03ceff4e371364f17c49ea370b6475cb0b7230..45d56852d8bd85126c66fb93fcc7a4c527a697b1:/windows/winhandl.c diff --git a/windows/winhandl.c b/windows/winhandl.c index d220e640..f515ee57 100644 --- a/windows/winhandl.c +++ b/windows/winhandl.c @@ -16,6 +16,17 @@ * 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 @@ -75,6 +86,11 @@ struct handle_input { 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. */ @@ -95,13 +111,41 @@ struct handle_input { static DWORD WINAPI handle_input_threadfunc(void *param) { struct handle_input *ctx = (struct handle_input *) param; + OVERLAPPED ovl, *povl; + HANDLE oev; + int 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 (povl) { + memset(povl, 0, sizeof(OVERLAPPED)); + povl->hEvent = oev; + } + ctx->readret = ReadFile(ctx->h, ctx->buffer, readlen, + &ctx->len, povl); + if (povl && !ctx->readret && GetLastError() == ERROR_IO_PENDING) { + WaitForSingleObject(povl->hEvent, INFINITE); + ctx->readret = GetOverlappedResult(ctx->h, povl, &ctx->len, FALSE); + } + if (!ctx->readret) ctx->len = 0; + if (ctx->readret && ctx->len == 0 && + (ctx->flags & HANDLE_FLAG_IGNOREEOF)) + continue; + SetEvent(ctx->ev_to_main); if (!ctx->len) @@ -112,6 +156,9 @@ static DWORD WINAPI handle_input_threadfunc(void *param) break; /* main thread told us to shut down */ } + if (povl) + CloseHandle(oev); + return 0; } @@ -122,7 +169,8 @@ static DWORD WINAPI handle_input_threadfunc(void *param) */ 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: @@ -163,6 +211,11 @@ struct handle_output { 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. */ @@ -191,6 +244,12 @@ struct handle_output { static DWORD WINAPI handle_output_threadfunc(void *param) { struct handle_output *ctx = (struct handle_output *) param; + OVERLAPPED ovl, *povl; + + if (ctx->flags & HANDLE_FLAG_OVERLAPPED) + povl = &ovl; + else + povl = NULL; while (1) { WaitForSingleObject(ctx->ev_from_main, INFINITE); @@ -198,8 +257,14 @@ static DWORD WINAPI handle_output_threadfunc(void *param) SetEvent(ctx->ev_to_main); break; } + if (povl) + memset(povl, 0, sizeof(OVERLAPPED)); ctx->writeret = WriteFile(ctx->h, ctx->buffer, ctx->len, - &ctx->lenwritten, NULL); + &ctx->lenwritten, povl); + if (povl && !ctx->writeret && GetLastError() == ERROR_IO_PENDING) + ctx->writeret = GetOverlappedResult(ctx->h, povl, + &ctx->lenwritten, TRUE); + SetEvent(ctx->ev_to_main); if (!ctx->writeret) break; @@ -264,37 +329,38 @@ static int handle_find_evtomain(void *av, void *bv) } 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.ev_to_main = CreateEvent(NULL, FALSE, FALSE, NULL); h->u.i.ev_from_main = CreateEvent(NULL, FALSE, FALSE, NULL); h->u.i.gotdata = gotdata; - h->u.i.busy = FALSE; h->u.i.defunct = FALSE; 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); - - handle_throttle(&h->u.i, 0); /* start first read operation */ + &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; @@ -307,13 +373,14 @@ struct handle *handle_output_new(HANDLE handle, handle_outputfn_t sentdata, h->u.o.privdata = privdata; bufchain_init(&h->u.o.queued_data); 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.i, 0, &out_threadid); return h; } @@ -393,6 +460,7 @@ void handle_free(struct handle *h) */ h->u.g.moribund = TRUE; h->u.g.done = TRUE; + h->u.g.busy = TRUE; SetEvent(h->u.g.ev_from_main); } } @@ -426,6 +494,7 @@ void handle_got_event(HANDLE event) handle_destroy(h); } else { h->u.g.done = TRUE; + h->u.g.busy = TRUE; SetEvent(h->u.g.ev_from_main); } return;