X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=blobdiff_plain;f=windows%2Fwinhandl.c;h=7c282fc7d5502f128f300d3ea09d942026d4c525;hb=a063e522970946bf7d5dc052079d7773c0dee76d;hp=f300962cb79f2d571ba4e1d6d005de6559bef79c;hpb=822628246ebf0036c83f0f6eba4233e518433249;p=PuTTY.git diff --git a/windows/winhandl.c b/windows/winhandl.c index f300962c..7c282fc7 100644 --- a/windows/winhandl.c +++ b/windows/winhandl.c @@ -65,6 +65,8 @@ struct handle_generic { void *privdata; /* for client to remember who they are */ }; +typedef enum { HT_INPUT, HT_OUTPUT, HT_FOREIGN } HandleType; + /* ---------------------------------------------------------------------- * Input threads. */ @@ -113,7 +115,7 @@ static DWORD WINAPI handle_input_threadfunc(void *param) struct handle_input *ctx = (struct handle_input *) param; OVERLAPPED ovl, *povl; HANDLE oev; - int readret, readlen; + int readret, readlen, finished; if (ctx->flags & HANDLE_FLAG_OVERLAPPED) { povl = &ovl; @@ -163,14 +165,32 @@ static DWORD WINAPI handle_input_threadfunc(void *param) (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) @@ -250,6 +270,7 @@ struct handle_output { * 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 @@ -262,21 +283,33 @@ 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) + 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)); + povl->hEvent = oev; + } + writeret = WriteFile(ctx->h, ctx->buffer, ctx->len, &ctx->lenwritten, povl); if (!writeret) @@ -293,10 +326,21 @@ static DWORD WINAPI handle_output_threadfunc(void *param) } SetEvent(ctx->ev_to_main); - if (!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; } @@ -311,19 +355,52 @@ static void handle_try_output(struct handle_output *ctx) 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; }; @@ -361,7 +438,7 @@ struct handle *handle_input_new(HANDLE handle, handle_inputfn_t gotdata, 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); @@ -389,7 +466,7 @@ struct handle *handle_output_new(HANDLE handle, handle_outputfn_t sentdata, 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); @@ -399,6 +476,7 @@ struct handle *handle_output_new(HANDLE handle, handle_outputfn_t sentdata, 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; @@ -407,19 +485,60 @@ struct handle *handle_output_new(HANDLE handle, handle_outputfn_t sentdata, 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; @@ -450,7 +569,7 @@ HANDLE *handle_get_events(int *nevents) 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); @@ -512,10 +631,12 @@ void handle_got_event(HANDLE event) 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); @@ -527,9 +648,10 @@ void handle_got_event(HANDLE event) return; } - if (!h->output) { + switch (h->type) { int backlog; + case HT_INPUT: h->u.i.busy = FALSE; /* @@ -539,13 +661,15 @@ void handle_got_event(HANDLE event) /* * EOF, or (nearly equivalently) read error. */ - h->u.i.gotdata(h, NULL, -h->u.i.readerr); 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; /* @@ -559,25 +683,31 @@ void handle_got_event(HANDLE event) * and mark the thread as defunct (because the output * thread is terminating by now). */ - h->u.o.sentdata(h, -h->u.o.writeerr); 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); }