hyung-hwan/hio
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

enhanced how to handle an error after mio_dev_make() failure by implementing fail_after_make callbacks in pipe, thr, pro

Browse Source 
decided to not call pthread_cancel in thr.c because it's too difficult to get it right
This commit is contained in:
hyung-hwan
2020-07-31 15:07:28 +00:00
parent a2e3195417
commit c230c92249
6 changed files with 720 additions and 57 deletions
Download Patch File Download Diff File Expand all files Collapse all files

5
mio/lib/http-thr.c
View File

@ -81,10 +81,8 @@ struct thr_state_t
mio_dev_sck_on_write_t client_org_on_write;
mio_dev_sck_on_disconnect_t client_org_on_disconnect;
mio_htrd_recbs_t client_htrd_org_recbs;
};
typedef struct thr_state_t thr_state_t;
struct thr_peer_xtn_t
@ -100,7 +98,6 @@ static void thr_state_halt_participating_devices (thr_state_t* thr_state)
MIO_DEBUG4 (thr_state->client->htts->mio, "HTTS(%p) - Halting participating devices in thr state %p(client=%p,peer=%p)\n", thr_state->client->htts, thr_state, thr_state->client->sck, thr_state->peer);
mio_dev_sck_halt (thr_state->client->sck);
/* check for peer as it may not have been started */
if (thr_state->peer) mio_dev_thr_halt (thr_state->peer);

58
mio/lib/pipe.c
View File

@ -58,8 +58,19 @@ static int dev_pipe_make_master (mio_dev_t* dev, void* ctx)
/* TODO: support a named pipe. use mkfifo()?
* support socketpair */
#if defined(HAVE_PIPE2) && defined(O_CLOEXEC) && defined(O_NONBLOCK)
if (pipe2(pfds, O_CLOEXEC | O_NONBLOCK) == -1)
{
if (errno != ENOSYS) goto pipe_error;
}
else goto pipe_done;
#endif
if (pipe(pfds) == -1)
{
#if defined(HAVE_PIPE2) && defined(O_CLOEXEC) && defined(O_NONBLOCK)
pipe_error:
#endif
mio_seterrwithsyserr (mio, 0, errno);
goto oops;
}
@ -67,11 +78,17 @@ static int dev_pipe_make_master (mio_dev_t* dev, void* ctx)
if (mio_makesyshndasync(mio, pfds[0]) <= -1 ||
mio_makesyshndasync(mio, pfds[1]) <= -1) goto oops;
if (mio_makesyshndcloexec(mio, pfds[0]) <= -1 ||
mio_makesyshndcloexec(mio, pfds[1]) <= -1) goto oops;
#if defined(HAVE_PIPE2) && defined(O_CLOEXEC) && defined(O_NONBLOCK)
pipe_done:
#endif
si.mi = info;
si.pfd = pfds[0];
si.dev_cap = MIO_DEV_CAP_IN | MIO_DEV_CAP_STREAM;
si.id = MIO_DEV_PIPE_IN;
pfds[0] = MIO_SYSHND_INVALID;
rdev->slave[MIO_DEV_PIPE_IN] = make_slave(mio, &si);
if (!rdev->slave[MIO_DEV_PIPE_IN]) goto oops;
rdev->slave_count++;
@ -80,7 +97,7 @@ static int dev_pipe_make_master (mio_dev_t* dev, void* ctx)
si.pfd = pfds[1];
si.dev_cap = MIO_DEV_CAP_OUT | MIO_DEV_CAP_STREAM;
si.id = MIO_DEV_PIPE_OUT;
pfds[1] = MIO_SYSHND_INVALID;
rdev->slave[MIO_DEV_PIPE_OUT] = make_slave(mio, &si);
if (!rdev->slave[MIO_DEV_PIPE_OUT]) goto oops;
rdev->slave_count++;
@ -97,20 +114,21 @@ static int dev_pipe_make_master (mio_dev_t* dev, void* ctx)
return 0;
oops:
for (i = 0; i < MIO_COUNTOF(rdev->slave); i++)
{
if (rdev->slave[i])
{
mio_dev_kill ((mio_dev_t*)rdev->slave[i]);
rdev->slave[i] = MIO_NULL;
}
else if (pfds[i] != MIO_SYSHND_INVALID)
{
close (pfds[i]);
}
}
rdev->slave_count = 0;
if (pfds[0] != MIO_SYSHND_INVALID) close (pfds[0]);
if (pfds[1] != MIO_SYSHND_INVALID) close (pfds[0]);
if (rdev->slave[0])
{
mio_dev_kill ((mio_dev_t*)rdev->slave[0]);
rdev->slave[0] = MIO_NULL;
}
if (rdev->slave[1])
{
mio_dev_kill ((mio_dev_t*)rdev->slave[1]);
rdev->slave[1] = MIO_NULL;
}
rdev->slave_count = 0;
return -1;
}
@ -204,6 +222,12 @@ static int dev_pipe_kill_slave (mio_dev_t* dev, int force)
return 0;
}
static void dev_pipe_fail_before_make_slave (void* ctx)
{
slave_info_t* si = (slave_info_t*)ctx;
close (si->pfd);
}
static int dev_pipe_read_slave (mio_dev_t* dev, void* buf, mio_iolen_t* len, mio_devaddr_t* srcaddr)
{
mio_dev_pipe_slave_t* pipe = (mio_dev_pipe_slave_t*)dev;
@ -242,7 +266,7 @@ static int dev_pipe_write_slave (mio_dev_t* dev, const void* data, mio_iolen_t*
if (MIO_UNLIKELY(*len <= 0))
{
/* this is an EOF indicator */
//mio_dev_halt (dev); /* halt this slave device to indicate EOF on the lower-level handle */*
/*mio_dev_halt (dev);*/ /* halt this slave device to indicate EOF on the lower-level handle */
if (MIO_LIKELY(pipe->pfd != MIO_SYSHND_INVALID)) /* halt() doesn't close the pipe immediately. so close the underlying pipe */
{
mio_dev_watch (dev, MIO_DEV_WATCH_STOP, 0);
@ -363,7 +387,7 @@ static mio_dev_mth_t dev_pipe_methods_slave =
{
dev_pipe_make_slave,
dev_pipe_kill_slave,
MIO_NULL,
dev_pipe_fail_before_make_slave,
dev_pipe_getsyshnd_slave,
dev_pipe_read_slave,

40
mio/lib/pro.c
View File

@ -346,10 +346,10 @@ static int dev_pro_make_master (mio_dev_t* dev, void* ctx)
si.dev_cap = MIO_DEV_CAP_OUT | MIO_DEV_CAP_STREAM;
si.id = MIO_DEV_PRO_IN;
pfds[1] = MIO_SYSHND_INVALID;
rdev->slave[MIO_DEV_PRO_IN] = make_slave(mio, &si);
if (!rdev->slave[MIO_DEV_PRO_IN]) goto oops;
pfds[1] = MIO_SYSHND_INVALID;
rdev->slave_count++;
}
@ -363,10 +363,10 @@ static int dev_pro_make_master (mio_dev_t* dev, void* ctx)
si.dev_cap = MIO_DEV_CAP_IN | MIO_DEV_CAP_STREAM;
si.id = MIO_DEV_PRO_OUT;
pfds[2] = MIO_SYSHND_INVALID;
rdev->slave[MIO_DEV_PRO_OUT] = make_slave(mio, &si);
if (!rdev->slave[MIO_DEV_PRO_OUT]) goto oops;
pfds[2] = MIO_SYSHND_INVALID;
rdev->slave_count++;
}
@ -380,10 +380,10 @@ static int dev_pro_make_master (mio_dev_t* dev, void* ctx)
si.dev_cap = MIO_DEV_CAP_IN | MIO_DEV_CAP_STREAM;
si.id = MIO_DEV_PRO_ERR;
pfds[4] = MIO_SYSHND_INVALID;
rdev->slave[MIO_DEV_PRO_ERR] = make_slave(mio, &si);
if (!rdev->slave[MIO_DEV_PRO_ERR]) goto oops;
pfds[4] = MIO_SYSHND_INVALID;
rdev->slave_count++;
}
@ -425,20 +425,6 @@ oops:
return -1;
}
static int dev_pro_make_slave (mio_dev_t* dev, void* ctx)
{
mio_dev_pro_slave_t* rdev = (mio_dev_pro_slave_t*)dev;
slave_info_t* si = (slave_info_t*)ctx;
rdev->dev_cap = si->dev_cap;
rdev->id = si->id;
rdev->pfd = si->pfd;
/* keep rdev->master to MIO_NULL. it's set to the right master
* device in dev_pro_make() */
return 0;
}
static int dev_pro_kill_master (mio_dev_t* dev, int force)
{
mio_t* mio = dev->mio;
@ -507,6 +493,20 @@ static int dev_pro_kill_master (mio_dev_t* dev, int force)
return 0;
}
static int dev_pro_make_slave (mio_dev_t* dev, void* ctx)
{
mio_dev_pro_slave_t* rdev = (mio_dev_pro_slave_t*)dev;
slave_info_t* si = (slave_info_t*)ctx;
rdev->dev_cap = si->dev_cap;
rdev->id = si->id;
rdev->pfd = si->pfd;
/* keep rdev->master to MIO_NULL. it's set to the right master
* device in dev_pro_make() */
return 0;
}
static int dev_pro_kill_slave (mio_dev_t* dev, int force)
{
mio_t* mio = dev->mio;
@ -554,6 +554,12 @@ static int dev_pro_kill_slave (mio_dev_t* dev, int force)
return 0;
}
static void dev_pro_fail_before_make_slave (void* ctx)
{
slave_info_t* si = (slave_info_t*)ctx;
close (si->pfd);
}
static int dev_pro_read_slave (mio_dev_t* dev, void* buf, mio_iolen_t* len, mio_devaddr_t* srcaddr)
{
mio_dev_pro_slave_t* pro = (mio_dev_pro_slave_t*)dev;

10
mio/lib/sck.c
View File

@ -381,8 +381,14 @@ static int dev_sck_make (mio_dev_t* dev, void* ctx)
return 0;
oops:
if (hnd != MIO_SYSHND_INVALID) close (hnd);
if (side_chan != MIO_SYSHND_INVALID) close (side_chan);
if (hnd != MIO_SYSHND_INVALID)
{
close (hnd);
}
if (side_chan != MIO_SYSHND_INVALID)
{
close (side_chan);
}
return -1;
}

90
mio/lib/thr.c
View File

@ -32,6 +32,7 @@
#include <sys/uio.h>
#include <pthread.h>
#include <stdio.h>
/* ========================================================================= */
struct mio_dev_thr_info_t
@ -64,13 +65,21 @@ static void free_thr_info_resources (mio_t* mio, mio_dev_thr_info_t* ti)
{
if (ti->thr_iop.rfd != MIO_SYSHND_INVALID)
{
close (ti->thr_iop.rfd);
ti->thr_iop.rfd = MIO_SYSHND_INVALID;
/* this function is called at the end of run_thr_func() and
* close() can be a thread cancellation point.
*
* i must invalidate ti->thr_iop.rfd calling close() with it.
* if resetting is done after close() and close() becomes a cancellation point,
* the invalidation operation gets skipped. */
mio_syshnd_t tmp = ti->thr_iop.rfd;
ti->thr_iop.rfd = MIO_SYSHND_INVALID;
close (tmp);
}
if (ti->thr_iop.wfd != MIO_SYSHND_INVALID)
{
close (ti->thr_iop.wfd);
mio_syshnd_t tmp = ti->thr_iop.wfd;
ti->thr_iop.wfd = MIO_SYSHND_INVALID;
close (tmp);
}
}
@ -119,9 +128,7 @@ static void* run_thr_func (void* ctx)
ti->thr_func (ti->mio, &ti->thr_iop, ti->thr_ctx);
/* This part may get partially executed or not executed if the thread is cancelled */
free_thr_info_resources (ti->mio, ti); /* TODO: check if the close() call inside this call completes when it becomes a cancellation point. if so, the code must get changed */
/* ---------------------------------------------------------- */
free_thr_info_resources (ti->mio, ti);
pthread_cleanup_pop (1);
pthread_exit (MIO_NULL);
@ -137,8 +144,20 @@ static int dev_thr_make_master (mio_dev_t* dev, void* ctx)
slave_info_t si;
int i;
#if defined(HAVE_PIPE2) && defined(O_CLOEXEC) && defined(O_NONBLOCK)
if (pipe2(&pfds[0], O_CLOEXEC | O_NONBLOCK) == -1 ||
pipe2(&pfds[2], O_CLOEXEC | O_NONBLOCK) == -1)
{
if (errno != ENOSYS) goto pipe_error;
}
else goto pipe_done;
#endif
if (pipe(&pfds[0]) == -1 || pipe(&pfds[2]) == -1)
{
#if defined(HAVE_PIPE2) && defined(O_CLOEXEC) && defined(O_NONBLOCK)
pipe_error:
#endif
mio_seterrwithsyserr (mio, 0, errno);
goto oops;
}
@ -146,26 +165,36 @@ static int dev_thr_make_master (mio_dev_t* dev, void* ctx)
if (mio_makesyshndasync(mio, pfds[1]) <= -1 ||
mio_makesyshndasync(mio, pfds[2]) <= -1) goto oops;
if (mio_makesyshndcloexec(mio, pfds[0]) <= -1 ||
mio_makesyshndcloexec(mio, pfds[1]) <= -1 ||
mio_makesyshndcloexec(mio, pfds[2]) <= -1 ||
mio_makesyshndcloexec(mio, pfds[1]) <= -1) goto oops;
#if defined(HAVE_PIPE2) && defined(O_CLOEXEC) && defined(O_NONBLOCK)
pipe_done:
#endif
si.mi = info;
si.pfd = pfds[1];
si.dev_cap = MIO_DEV_CAP_OUT | MIO_DEV_CAP_STREAM;
si.id = MIO_DEV_THR_IN;
/* invalidate pfds[1] before calling make_slave() because when it fails, the
* fail_before_make(dev_thr_fail_before_make_slave) and kill(dev_thr_kill_slave) callbacks close si.pfd */
pfds[1] = MIO_SYSHND_INVALID;
rdev->slave[MIO_DEV_THR_IN] = make_slave(mio, &si);
if (!rdev->slave[MIO_DEV_THR_IN]) goto oops;
pfds[1] = MIO_SYSHND_INVALID;
rdev->slave_count++;
si.mi = info;
si.pfd = pfds[2];
si.dev_cap = MIO_DEV_CAP_IN | MIO_DEV_CAP_STREAM;
si.id = MIO_DEV_THR_OUT;
/* invalidate pfds[2] before calling make_slave() because when it fails, the
* fail_before_make(dev_thr_fail_before_make_slave) and kill(dev_thr_kill_slave) callbacks close si.pfd */
pfds[2] = MIO_SYSHND_INVALID;
rdev->slave[MIO_DEV_THR_OUT] = make_slave(mio, &si);
if (!rdev->slave[MIO_DEV_THR_OUT]) goto oops;
pfds[2] = MIO_SYSHND_INVALID;
rdev->slave_count++;
for (i = 0; i < MIO_COUNTOF(rdev->slave); i++)
@ -200,6 +229,10 @@ static int dev_thr_make_master (mio_dev_t* dev, void* ctx)
mio_freemem (mio, ti);
goto oops;
}
/* the thread function is in charge of these two file descriptors */
pfds[0] = MIO_SYSHND_INVALID;
pfds[3] = MIO_SYSHND_INVALID;
}
/* ---------------------------------------------------------- */
@ -209,7 +242,10 @@ static int dev_thr_make_master (mio_dev_t* dev, void* ctx)
oops:
for (i = 0; i < MIO_COUNTOF(pfds); i++)
{
if (pfds[i] != MIO_SYSHND_INVALID) close (pfds[i]);
if (pfds[i] != MIO_SYSHND_INVALID)
{
close (pfds[i]);
}
}
for (i = MIO_COUNTOF(rdev->slave); i > 0; )
@ -248,7 +284,10 @@ static int dev_thr_kill_master (mio_dev_t* dev, int force)
int i;
ti = rdev->thr_info;
pthread_cancel (ti->thr_hnd);
/* pthread_cancel() seems to create some dangling file descriptors not closed properly.
* i don't seem to get it working correctly as of now. proper cancellation point management
* is very difficult. without pthread_cancel() here, higher pressure on cfmb is expected */
/*pthread_cancel (ti->thr_hnd); */
if (rdev->slave_count > 0)
{
@ -269,17 +308,26 @@ static int dev_thr_kill_master (mio_dev_t* dev, int force)
}
}
rdev->thr_info = MIO_NULL;
if (ti->thr_done)
{
pthread_detach (ti->thr_hnd); /* pthread_join() may be blocking. */
pthread_detach (ti->thr_hnd); /* pthread_join() may be blocking. detach the thread instead */
free_thr_info_resources (mio, ti);
mio_freemem (mio, ti);
}
else
{
#if 0
/* since pthread_join can be blocking, i'd schedule a resource destroyer with mio_addcfmb().
* see after #else */
pthread_join (ti->thr_hnd, MIO_NULL);
free_thr_info_resources (mio, ti);
mio_freemem (mio, ti);
#else
/* schedule a resource destroyer */
mio_addcfmb (mio, ti, ready_to_free_thr_info);
#endif
}
rdev->thr_info = MIO_NULL;
if (rdev->on_close) rdev->on_close (rdev, MIO_DEV_THR_MASTER);
return 0;
@ -332,6 +380,14 @@ static int dev_thr_kill_slave (mio_dev_t* dev, int force)
return 0;
}
static void dev_thr_fail_before_make_slave (void* ctx)
{
slave_info_t* si = (slave_info_t*)ctx;
/* mio_dev_make() failed before it called the make() callback.
* i will close the pipe fd here instead of in the caller of mio_dev_make() */
close (si->pfd);
}
static int dev_thr_read_slave (mio_dev_t* dev, void* buf, mio_iolen_t* len, mio_devaddr_t* srcaddr)
{
mio_dev_thr_slave_t* thr = (mio_dev_thr_slave_t*)dev;
@ -377,7 +433,7 @@ static int dev_thr_write_slave (mio_dev_t* dev, const void* data, mio_iolen_t* l
if (MIO_UNLIKELY(*len <= 0))
{
/* this is an EOF indicator */
/* It isn't apthrpriate to call mio_dev_halt(thr) or mio_dev_thr_close(thr->master, MIO_DEV_THR_IN)
/* It isn't appropriate to call mio_dev_halt(thr) or mio_dev_thr_close(thr->master, MIO_DEV_THR_IN)
* as those functions destroy the device itself */
if (MIO_LIKELY(thr->pfd != MIO_SYSHND_INVALID))
{
@ -523,7 +579,7 @@ static mio_dev_mth_t dev_thr_methods_slave =
{
dev_thr_make_slave,
dev_thr_kill_slave,
MIO_NULL,
dev_thr_fail_before_make_slave,
dev_thr_getsyshnd_slave,
dev_thr_read_slave,