Reduce code duplication in pipe event filters

Use the f_event callback for checking event state within the pipe
event filters. This enables the same f_modify and f_process functions
to handle the different filter types.

OK anton@

diff --git a/sys/kern/sys_pipe.c b/sys/kern/sys_pipe.c
index 3444841..92527b2 100644 (file)
--- a/sys/kern/sys_pipe.c
+++ b/sys/kern/sys_pipe.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: sys_pipe.c,v 1.133 2021/12/13 14:56:55 visa Exp $     */
+/*     $OpenBSD: sys_pipe.c,v 1.134 2022/02/12 14:07:26 visa Exp $     */
 
 /*
  * Copyright (c) 1996 John S. Dyson
@@ -78,25 +78,18 @@ static const struct fileops pipeops = {
 
 void   filt_pipedetach(struct knote *kn);
 int    filt_piperead(struct knote *kn, long hint);
-int    filt_pipereadmodify(struct kevent *kev, struct knote *kn);
-int    filt_pipereadprocess(struct knote *kn, struct kevent *kev);
-int    filt_piperead_common(struct knote *kn, struct pipe *rpipe);
 int    filt_pipewrite(struct knote *kn, long hint);
-int    filt_pipewritemodify(struct kevent *kev, struct knote *kn);
-int    filt_pipewriteprocess(struct knote *kn, struct kevent *kev);
-int    filt_pipewrite_common(struct knote *kn, struct pipe *rpipe);
 int    filt_pipeexcept(struct knote *kn, long hint);
-int    filt_pipeexceptmodify(struct kevent *kev, struct knote *kn);
-int    filt_pipeexceptprocess(struct knote *kn, struct kevent *kev);
-int    filt_pipeexcept_common(struct knote *kn, struct pipe *rpipe);
+int    filt_pipemodify(struct kevent *kev, struct knote *kn);
+int    filt_pipeprocess(struct knote *kn, struct kevent *kev);
 
 const struct filterops pipe_rfiltops = {
        .f_flags        = FILTEROP_ISFD | FILTEROP_MPSAFE,
        .f_attach       = NULL,
        .f_detach       = filt_pipedetach,
        .f_event        = filt_piperead,
-       .f_modify       = filt_pipereadmodify,
-       .f_process      = filt_pipereadprocess,
+       .f_modify       = filt_pipemodify,
+       .f_process      = filt_pipeprocess,
 };
 
 const struct filterops pipe_wfiltops = {
@@ -104,8 +97,8 @@ const struct filterops pipe_wfiltops = {
        .f_attach       = NULL,
        .f_detach       = filt_pipedetach,
        .f_event        = filt_pipewrite,
-       .f_modify       = filt_pipewritemodify,
-       .f_process      = filt_pipewriteprocess,
+       .f_modify       = filt_pipemodify,
+       .f_process      = filt_pipeprocess,
 };
 
 const struct filterops pipe_efiltops = {
@@ -113,8 +106,8 @@ const struct filterops pipe_efiltops = {
        .f_attach       = NULL,
        .f_detach       = filt_pipedetach,
        .f_event        = filt_pipeexcept,
-       .f_modify       = filt_pipeexceptmodify,
-       .f_process      = filt_pipeexceptprocess,
+       .f_modify       = filt_pipemodify,
+       .f_process      = filt_pipeprocess,
 };
 
 /*
@@ -954,9 +947,9 @@ filt_pipedetach(struct knote *kn)
 }
 
 int
-filt_piperead_common(struct knote *kn, struct pipe *rpipe)
+filt_piperead(struct knote *kn, long hint)
 {
-       struct pipe *wpipe;
+       struct pipe *rpipe = kn->kn_fp->f_data, *wpipe;
 
        rw_assert_wrlock(rpipe->pipe_lock);
 
@@ -975,49 +968,9 @@ filt_piperead_common(struct knote *kn, struct pipe *rpipe)
 }
 
 int
-filt_piperead(struct knote *kn, long hint)
-{
-       struct pipe *rpipe = kn->kn_fp->f_data;
-
-       return (filt_piperead_common(kn, rpipe));
-}
-
-int
-filt_pipereadmodify(struct kevent *kev, struct knote *kn)
-{
-       struct pipe *rpipe = kn->kn_fp->f_data;
-       int active;
-
-       rw_enter_write(rpipe->pipe_lock);
-       knote_modify(kev, kn);
-       active = filt_piperead_common(kn, rpipe);
-       rw_exit_write(rpipe->pipe_lock);
-
-       return (active);
-}
-
-int
-filt_pipereadprocess(struct knote *kn, struct kevent *kev)
-{
-       struct pipe *rpipe = kn->kn_fp->f_data;
-       int active;
-
-       rw_enter_write(rpipe->pipe_lock);
-       if (kev != NULL && (kn->kn_flags & EV_ONESHOT))
-               active = 1;
-       else
-               active = filt_piperead_common(kn, rpipe);
-       if (active)
-               knote_submit(kn, kev);
-       rw_exit_write(rpipe->pipe_lock);
-
-       return (active);
-}
-
-int
-filt_pipewrite_common(struct knote *kn, struct pipe *rpipe)
+filt_pipewrite(struct knote *kn, long hint)
 {
-       struct pipe *wpipe;
+       struct pipe *rpipe = kn->kn_fp->f_data, *wpipe;
 
        rw_assert_wrlock(rpipe->pipe_lock);
 
@@ -1036,49 +989,9 @@ filt_pipewrite_common(struct knote *kn, struct pipe *rpipe)
 }
 
 int
-filt_pipewrite(struct knote *kn, long hint)
-{
-       struct pipe *rpipe = kn->kn_fp->f_data;
-
-       return (filt_pipewrite_common(kn, rpipe));
-}
-
-int
-filt_pipewritemodify(struct kevent *kev, struct knote *kn)
-{
-       struct pipe *rpipe = kn->kn_fp->f_data;
-       int active;
-
-       rw_enter_write(rpipe->pipe_lock);
-       knote_modify(kev, kn);
-       active = filt_pipewrite_common(kn, rpipe);
-       rw_exit_write(rpipe->pipe_lock);
-
-       return (active);
-}
-
-int
-filt_pipewriteprocess(struct knote *kn, struct kevent *kev)
-{
-       struct pipe *rpipe = kn->kn_fp->f_data;
-       int active;
-
-       rw_enter_write(rpipe->pipe_lock);
-       if (kev != NULL && (kn->kn_flags & EV_ONESHOT))
-               active = 1;
-       else
-               active = filt_pipewrite_common(kn, rpipe);
-       if (active)
-               knote_submit(kn, kev);
-       rw_exit_write(rpipe->pipe_lock);
-
-       return (active);
-}
-
-int
-filt_pipeexcept_common(struct knote *kn, struct pipe *rpipe)
+filt_pipeexcept(struct knote *kn, long hint)
 {
-       struct pipe *wpipe;
+       struct pipe *rpipe = kn->kn_fp->f_data, *wpipe;
        int active = 0;
 
        rw_assert_wrlock(rpipe->pipe_lock);
@@ -1096,29 +1009,21 @@ filt_pipeexcept_common(struct knote *kn, struct pipe *rpipe)
 }
 
 int
-filt_pipeexcept(struct knote *kn, long hint)
-{
-       struct pipe *rpipe = kn->kn_fp->f_data;
-
-       return (filt_pipeexcept_common(kn, rpipe));
-}
-
-int
-filt_pipeexceptmodify(struct kevent *kev, struct knote *kn)
+filt_pipemodify(struct kevent *kev, struct knote *kn)
 {
        struct pipe *rpipe = kn->kn_fp->f_data;
        int active;
 
        rw_enter_write(rpipe->pipe_lock);
        knote_modify(kev, kn);
-       active = filt_pipeexcept_common(kn, rpipe);
+       active = kn->kn_fop->f_event(kn, 0);
        rw_exit_write(rpipe->pipe_lock);
 
        return (active);
 }
 
 int
-filt_pipeexceptprocess(struct knote *kn, struct kevent *kev)
+filt_pipeprocess(struct knote *kn, struct kevent *kev)
 {
        struct pipe *rpipe = kn->kn_fp->f_data;
        int active;
@@ -1127,7 +1032,7 @@ filt_pipeexceptprocess(struct knote *kn, struct kevent *kev)
        if (kev != NULL && (kn->kn_flags & EV_ONESHOT))
                active = 1;
        else
-               active = filt_pipeexcept_common(kn, rpipe);
+               active = kn->kn_fop->f_event(kn, 0);
        if (active)
                knote_submit(kn, kev);
        rw_exit_write(rpipe->pipe_lock);