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Fix select-related bugs: missing cancellations led to potentially forgetting notifies, especially in the case of async drivers

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This commit is contained in:
Erik van der Kouwe 2010-10-08 12:50:52 +00:00
parent 470a185909
commit 9235536f38
1 changed files with 6 additions and 8 deletions
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14
servers/vfs/select.c
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@ -170,7 +170,10 @@ PUBLIC int do_select(void)
} }
} }
if (type == -1) return(EBADF); if (type == -1) {
select_cancel_all(se);
return(EBADF);
}
se->type[fd] = type; se->type[fd] = type;
/* Test filp for select operations if not already done so. e.g., files /* Test filp for select operations if not already done so. e.g., files
@ -210,7 +213,6 @@ PUBLIC int do_select(void)
*/ */
r = copy_fdsets(se, se->nfds, TO_PROC); r = copy_fdsets(se, se->nfds, TO_PROC);
select_cancel_all(se); select_cancel_all(se);
se->requestor = NULL;
if (r != OK) return(r); if (r != OK) return(r);
else return(se->nreadyfds); else return(se->nreadyfds);
@ -321,7 +323,6 @@ PRIVATE int select_request_asynch(struct filp *f, int *ops, int block)
return(SEL_DEFERRED); return(SEL_DEFERRED);
} }
/*===========================================================================* /*===========================================================================*
* select_major_match * * select_major_match *
*===========================================================================*/ *===========================================================================*/
@ -433,6 +434,7 @@ PRIVATE void select_cancel_all(struct selectentry *e)
{ {
int fd; int fd;
e->requestor = NULL;
for(fd = 0; fd < e->nfds; fd++) { for(fd = 0; fd < e->nfds; fd++) {
struct filp *fp; struct filp *fp;
fp = e->filps[fd]; fp = e->filps[fd];
@ -516,7 +518,6 @@ PRIVATE void select_return(struct selectentry *se, int r)
select_cancel_all(se); select_cancel_all(se);
copy_fdsets(se, se->nfds, TO_PROC); /* FIXME, return error status */ copy_fdsets(se, se->nfds, TO_PROC); /* FIXME, return error status */
select_wakeup(se, r ? r : se->nreadyfds); select_wakeup(se, r ? r : se->nreadyfds);
se->requestor = NULL;
} }
@ -642,7 +643,6 @@ PUBLIC void select_forget(int proc_e)
} }
select_cancel_all(&selecttab[s]); select_cancel_all(&selecttab[s]);
selecttab[s].requestor = NULL;
return; return;
} }
@ -964,9 +964,7 @@ int slot;
se->deferred= FALSE; se->deferred= FALSE;
} }
if (se->nreadyfds > 0 || !se->block) { if (se->nreadyfds > 0 || !se->block) {
copy_fdsets(se, se->nfds, TO_PROC); /* FIXME, return error */ select_return(se, 0);
select_wakeup(se, se->nreadyfds);
se->requestor = NULL;
} }
} }