/* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <apr_lib.h>
#include <apr_atomic.h>
#include <apr_strings.h>
#include <apr_time.h>
#include <apr_buckets.h>
#include <apr_thread_mutex.h>
#include <apr_thread_cond.h>
#include <httpd.h>
#include <http_protocol.h>
#include <http_log.h>
#include "h2_private.h"
#include "h2_util.h"
#include "h2_bucket_beam.h"
static void h2_beam_emitted(h2_bucket_beam *beam, h2_beam_proxy *proxy);
#define H2_BPROXY_NEXT(e) APR_RING_NEXT((e), link)
#define H2_BPROXY_PREV(e) APR_RING_PREV((e), link)
#define H2_BPROXY_REMOVE(e) APR_RING_REMOVE((e), link)
#define H2_BPROXY_LIST_INIT(b) APR_RING_INIT(&(b)->list, h2_beam_proxy, link);
#define H2_BPROXY_LIST_SENTINEL(b) APR_RING_SENTINEL(&(b)->list, h2_beam_proxy, link)
#define H2_BPROXY_LIST_EMPTY(b) APR_RING_EMPTY(&(b)->list, h2_beam_proxy, link)
#define H2_BPROXY_LIST_FIRST(b) APR_RING_FIRST(&(b)->list)
#define H2_BPROXY_LIST_LAST(b) APR_RING_LAST(&(b)->list)
#define H2_PROXY_BLIST_INSERT_HEAD(b, e) do { \
h2_beam_proxy *ap__b = (e); \
APR_RING_INSERT_HEAD(&(b)->list, ap__b, h2_beam_proxy, link); \
} while (0)
#define H2_BPROXY_LIST_INSERT_TAIL(b, e) do { \
h2_beam_proxy *ap__b = (e); \
APR_RING_INSERT_TAIL(&(b)->list, ap__b, h2_beam_proxy, link); \
} while (0)
#define H2_BPROXY_LIST_CONCAT(a, b) do { \
APR_RING_CONCAT(&(a)->list, &(b)->list, h2_beam_proxy, link); \
} while (0)
#define H2_BPROXY_LIST_PREPEND(a, b) do { \
APR_RING_PREPEND(&(a)->list, &(b)->list, h2_beam_proxy, link); \
} while (0)
/*******************************************************************************
* beam bucket with reference to beam and bucket it represents
******************************************************************************/
const apr_bucket_type_t h2_bucket_type_beam;
#define H2_BUCKET_IS_BEAM(e) (e->type == &h2_bucket_type_beam)
struct h2_beam_proxy {
apr_bucket_refcount refcount;
APR_RING_ENTRY(h2_beam_proxy) link;
h2_bucket_beam *beam;
apr_bucket *bsender;
apr_size_t n;
};
static const char Dummy = '\0';
static apr_status_t beam_bucket_read(apr_bucket *b, const char **str,
apr_size_t *len, apr_read_type_e block)
{
h2_beam_proxy *d = b->data;
if (d->bsender) {
const char *data;
apr_status_t status = apr_bucket_read(d->bsender, &data, len, block);
if (status == APR_SUCCESS) {
*str = data + b->start;
*len = b->length;
}
return status;
}
*str = &Dummy;
*len = 0;
return APR_ECONNRESET;
}
static void beam_bucket_destroy(void *data)
{
h2_beam_proxy *d = data;
if (apr_bucket_shared_destroy(d)) {
/* When the beam gets destroyed before this bucket, it will
* NULLify its reference here. This is not protected by a mutex,
* so it will not help with race conditions.
* But it lets us shut down memory pool with circulare beam
* references. */
if (d->beam) {
h2_beam_emitted(d->beam, d);
}
apr_bucket_free(d);
}
}
static apr_bucket * h2_beam_bucket_make(apr_bucket *b,
h2_bucket_beam *beam,
apr_bucket *bsender, apr_size_t n)
{
h2_beam_proxy *d;
d = apr_bucket_alloc(sizeof(*d), b->list);
H2_BPROXY_LIST_INSERT_TAIL(&beam->proxies, d);
d->beam = beam;
d->bsender = bsender;
d->n = n;
b = apr_bucket_shared_make(b, d, 0, bsender? bsender->length : 0);
b->type = &h2_bucket_type_beam;
return b;
}
static apr_bucket *h2_beam_bucket_create(h2_bucket_beam *beam,
apr_bucket *bsender,
apr_bucket_alloc_t *list,
apr_size_t n)
{
apr_bucket *b = apr_bucket_alloc(sizeof(*b), list);
APR_BUCKET_INIT(b);
b->free = apr_bucket_free;
b->list = list;
return h2_beam_bucket_make(b, beam, bsender, n);
}
const apr_bucket_type_t h2_bucket_type_beam = {
"BEAM", 5, APR_BUCKET_DATA,
beam_bucket_destroy,
beam_bucket_read,
apr_bucket_setaside_noop,
apr_bucket_shared_split,
apr_bucket_shared_copy
};
/*******************************************************************************
* h2_blist, a brigade without allocations
******************************************************************************/
static apr_array_header_t *beamers;
static apr_status_t cleanup_beamers(void *dummy)
{
(void)dummy;
beamers = NULL;
return APR_SUCCESS;
}
void h2_register_bucket_beamer(h2_bucket_beamer *beamer)
{
if (!beamers) {
apr_pool_cleanup_register(apr_hook_global_pool, NULL,
cleanup_beamers, apr_pool_cleanup_null);
beamers = apr_array_make(apr_hook_global_pool, 10,
sizeof(h2_bucket_beamer*));
}
APR_ARRAY_PUSH(beamers, h2_bucket_beamer*) = beamer;
}
static apr_bucket *h2_beam_bucket(h2_bucket_beam *beam,
apr_bucket_brigade *dest,
const apr_bucket *src)
{
apr_bucket *b = NULL;
int i;
if (beamers) {
for (i = 0; i < beamers->nelts && b == NULL; ++i) {
h2_bucket_beamer *beamer;
beamer = APR_ARRAY_IDX(beamers, i, h2_bucket_beamer*);
b = beamer(beam, dest, src);
}
}
return b;
}
/*******************************************************************************
* bucket beam that can transport buckets across threads
******************************************************************************/
static void mutex_leave(void *ctx, apr_thread_mutex_t *lock)
{
apr_thread_mutex_unlock(lock);
}
static apr_status_t mutex_enter(void *ctx, h2_beam_lock *pbl)
{
h2_bucket_beam *beam = ctx;
pbl->mutex = beam->lock;
pbl->leave = mutex_leave;
return apr_thread_mutex_lock(pbl->mutex);
}
static apr_status_t enter_yellow(h2_bucket_beam *beam, h2_beam_lock *pbl)
{
return mutex_enter(beam, pbl);
}
static void leave_yellow(h2_bucket_beam *beam, h2_beam_lock *pbl)
{
if (pbl->leave) {
pbl->leave(pbl->leave_ctx, pbl->mutex);
}
}
static apr_off_t bucket_mem_used(apr_bucket *b)
{
if (APR_BUCKET_IS_FILE(b)) {
return 0;
}
else {
/* should all have determinate length */
return b->length;
}
}
static int report_consumption(h2_bucket_beam *beam, h2_beam_lock *pbl)
{
int rv = 0;
apr_off_t len = beam->received_bytes - beam->cons_bytes_reported;
h2_beam_io_callback *cb = beam->cons_io_cb;
if (len > 0) {
if (cb) {
void *ctx = beam->cons_ctx;
if (pbl) leave_yellow(beam, pbl);
cb(ctx, beam, len);
if (pbl) enter_yellow(beam, pbl);
rv = 1;
}
beam->cons_bytes_reported += len;
}
return rv;
}
static void report_prod_io(h2_bucket_beam *beam, int force, h2_beam_lock *pbl)
{
apr_off_t len = beam->sent_bytes - beam->prod_bytes_reported;
if (force || len > 0) {
h2_beam_io_callback *cb = beam->prod_io_cb;
if (cb) {
void *ctx = beam->prod_ctx;
leave_yellow(beam, pbl);
cb(ctx, beam, len);
enter_yellow(beam, pbl);
}
beam->prod_bytes_reported += len;
}
}
static apr_size_t calc_buffered(h2_bucket_beam *beam)
{
apr_size_t len = 0;
apr_bucket *b;
for (b = H2_BLIST_FIRST(&beam->send_list);
b != H2_BLIST_SENTINEL(&beam->send_list);
b = APR_BUCKET_NEXT(b)) {
if (b->length == ((apr_size_t)-1)) {
/* do not count */
}
else if (APR_BUCKET_IS_FILE(b)) {
/* if unread, has no real mem footprint. */
}
else {
len += b->length;
}
}
return len;
}
static void r_purge_sent(h2_bucket_beam *beam)
{
apr_bucket *b;
/* delete all sender buckets in purge brigade, needs to be called
* from sender thread only */
while (!H2_BLIST_EMPTY(&beam->purge_list)) {
b = H2_BLIST_FIRST(&beam->purge_list);
apr_bucket_delete(b);
}
}
static apr_size_t calc_space_left(h2_bucket_beam *beam)
{
if (beam->max_buf_size > 0) {
apr_off_t len = calc_buffered(beam);
return (beam->max_buf_size > len? (beam->max_buf_size - len) : 0);
}
return APR_SIZE_MAX;
}
static int buffer_is_empty(h2_bucket_beam *beam)
{
return ((!beam->recv_buffer || APR_BRIGADE_EMPTY(beam->recv_buffer))
&& H2_BLIST_EMPTY(&beam->send_list));
}
static apr_status_t wait_empty(h2_bucket_beam *beam, apr_read_type_e block,
apr_thread_mutex_t *lock)
{
apr_status_t rv = APR_SUCCESS;
while (!buffer_is_empty(beam) && APR_SUCCESS == rv) {
if (APR_BLOCK_READ != block || !lock) {
rv = APR_EAGAIN;
}
else if (beam->timeout > 0) {
rv = apr_thread_cond_timedwait(beam->change, lock, beam->timeout);
}
else {
rv = apr_thread_cond_wait(beam->change, lock);
}
}
return rv;
}
static apr_status_t wait_not_empty(h2_bucket_beam *beam, apr_read_type_e block,
apr_thread_mutex_t *lock)
{
apr_status_t rv = APR_SUCCESS;
while (buffer_is_empty(beam) && APR_SUCCESS == rv) {
if (beam->aborted) {
rv = APR_ECONNABORTED;
}
else if (beam->closed) {
rv = APR_EOF;
}
else if (APR_BLOCK_READ != block || !lock) {
rv = APR_EAGAIN;
}
else if (beam->timeout > 0) {
rv = apr_thread_cond_timedwait(beam->change, lock, beam->timeout);
}
else {
rv = apr_thread_cond_wait(beam->change, lock);
}
}
return rv;
}
static apr_status_t wait_not_full(h2_bucket_beam *beam, apr_read_type_e block,
apr_size_t *pspace_left, h2_beam_lock *bl)
{
apr_status_t rv = APR_SUCCESS;
apr_size_t left;
while (0 == (left = calc_space_left(beam)) && APR_SUCCESS == rv) {
if (beam->aborted) {
rv = APR_ECONNABORTED;
}
else if (block != APR_BLOCK_READ || !bl->mutex) {
rv = APR_EAGAIN;
}
else {
if (beam->timeout > 0) {
rv = apr_thread_cond_timedwait(beam->change, bl->mutex, beam->timeout);
}
else {
rv = apr_thread_cond_wait(beam->change, bl->mutex);
}
}
}
*pspace_left = left;
return rv;
}
static void h2_beam_emitted(h2_bucket_beam *beam, h2_beam_proxy *proxy)
{
h2_beam_lock bl;
apr_bucket *b, *next;
if (enter_yellow(beam, &bl) == APR_SUCCESS) {
/* even when beam buckets are split, only the one where
* refcount drops to 0 will call us */
H2_BPROXY_REMOVE(proxy);
/* invoked from receiver thread, the last beam bucket for the send
* bucket is about to be destroyed.
* remove it from the hold, where it should be now */
if (proxy->bsender) {
for (b = H2_BLIST_FIRST(&beam->hold_list);
b != H2_BLIST_SENTINEL(&beam->hold_list);
b = APR_BUCKET_NEXT(b)) {
if (b == proxy->bsender) {
break;
}
}
if (b != H2_BLIST_SENTINEL(&beam->hold_list)) {
/* bucket is in hold as it should be, mark this one
* and all before it for purging. We might have placed meta
* buckets without a receiver proxy into the hold before it
* and schedule them for purging now */
for (b = H2_BLIST_FIRST(&beam->hold_list);
b != H2_BLIST_SENTINEL(&beam->hold_list);
b = next) {
next = APR_BUCKET_NEXT(b);
if (b == proxy->bsender) {
APR_BUCKET_REMOVE(b);
H2_BLIST_INSERT_TAIL(&beam->purge_list, b);
break;
}
else if (APR_BUCKET_IS_METADATA(b)) {
APR_BUCKET_REMOVE(b);
H2_BLIST_INSERT_TAIL(&beam->purge_list, b);
}
else {
/* another data bucket before this one in hold. this
* is normal since DATA buckets need not be destroyed
* in order */
}
}
proxy->bsender = NULL;
}
else {
/* it should be there unless we screwed up */
ap_log_perror(APLOG_MARK, APLOG_WARNING, 0, beam->send_pool,
APLOGNO(03384) "h2_beam(%d-%s): emitted bucket not "
"in hold, n=%d", beam->id, beam->tag,
(int)proxy->n);
ap_assert(!proxy->bsender);
}
}
/* notify anyone waiting on space to become available */
if (!bl.mutex) {
r_purge_sent(beam);
}
else {
apr_thread_cond_broadcast(beam->change);
}
leave_yellow(beam, &bl);
}
}
static void h2_blist_cleanup(h2_blist *bl)
{
apr_bucket *e;
while (!H2_BLIST_EMPTY(bl)) {
e = H2_BLIST_FIRST(bl);
apr_bucket_delete(e);
}
}
static apr_status_t beam_close(h2_bucket_beam *beam)
{
if (!beam->closed) {
beam->closed = 1;
apr_thread_cond_broadcast(beam->change);
}
return APR_SUCCESS;
}
int h2_beam_is_closed(h2_bucket_beam *beam)
{
return beam->closed;
}
static int pool_register(h2_bucket_beam *beam, apr_pool_t *pool,
apr_status_t (*cleanup)(void *))
{
if (pool && pool != beam->pool) {
apr_pool_pre_cleanup_register(pool, beam, cleanup);
return 1;
}
return 0;
}
static int pool_kill(h2_bucket_beam *beam, apr_pool_t *pool,
apr_status_t (*cleanup)(void *)) {
if (pool && pool != beam->pool) {
apr_pool_cleanup_kill(pool, beam, cleanup);
return 1;
}
return 0;
}
static apr_status_t beam_recv_cleanup(void *data)
{
h2_bucket_beam *beam = data;
/* receiver pool has gone away, clear references */
beam->recv_buffer = NULL;
beam->recv_pool = NULL;
return APR_SUCCESS;
}
static apr_status_t beam_send_cleanup(void *data)
{
h2_bucket_beam *beam = data;
/* sender is going away, clear up all references to its memory */
r_purge_sent(beam);
h2_blist_cleanup(&beam->send_list);
report_consumption(beam, NULL);
while (!H2_BPROXY_LIST_EMPTY(&beam->proxies)) {
h2_beam_proxy *proxy = H2_BPROXY_LIST_FIRST(&beam->proxies);
H2_BPROXY_REMOVE(proxy);
proxy->beam = NULL;
proxy->bsender = NULL;
}
h2_blist_cleanup(&beam->purge_list);
h2_blist_cleanup(&beam->hold_list);
beam->send_pool = NULL;
return APR_SUCCESS;
}
static void beam_set_send_pool(h2_bucket_beam *beam, apr_pool_t *pool)
{
if (beam->send_pool != pool) {
if (beam->send_pool && beam->send_pool != beam->pool) {
pool_kill(beam, beam->send_pool, beam_send_cleanup);
beam_send_cleanup(beam);
}
beam->send_pool = pool;
pool_register(beam, beam->send_pool, beam_send_cleanup);
}
}
static void recv_buffer_cleanup(h2_bucket_beam *beam, h2_beam_lock *bl)
{
if (beam->recv_buffer && !APR_BRIGADE_EMPTY(beam->recv_buffer)) {
apr_bucket_brigade *bb = beam->recv_buffer;
apr_off_t bblen = 0;
beam->recv_buffer = NULL;
apr_brigade_length(bb, 0, &bblen);
beam->received_bytes += bblen;
/* need to do this unlocked since bucket destroy might
* call this beam again. */
if (bl) leave_yellow(beam, bl);
apr_brigade_destroy(bb);
if (bl) enter_yellow(beam, bl);
apr_thread_cond_broadcast(beam->change);
if (beam->cons_ev_cb) {
beam->cons_ev_cb(beam->cons_ctx, beam);
}
}
}
static apr_status_t beam_cleanup(h2_bucket_beam *beam, int from_pool)
{
apr_status_t status = APR_SUCCESS;
int safe_send = (beam->owner == H2_BEAM_OWNER_SEND);
int safe_recv = (beam->owner == H2_BEAM_OWNER_RECV);
/*
* Owner of the beam is going away, depending on which side it owns,
* cleanup strategies will differ.
*
* In general, receiver holds references to memory from sender.
* Clean up receiver first, if safe, then cleanup sender, if safe.
*/
/* When called from pool destroy, io callbacks are disabled */
if (from_pool) {
beam->cons_io_cb = NULL;
}
/* When modify send is not safe, this means we still have multi-thread
* protection and the owner is receiving the buckets. If the sending
* side has not gone away, this means we could have dangling buckets
* in our lists that never get destroyed. This should not happen. */
ap_assert(safe_send || !beam->send_pool);
if (!H2_BLIST_EMPTY(&beam->send_list)) {
ap_assert(beam->send_pool);
}
if (safe_recv) {
if (beam->recv_pool) {
pool_kill(beam, beam->recv_pool, beam_recv_cleanup);
beam->recv_pool = NULL;
}
recv_buffer_cleanup(beam, NULL);
}
else {
beam->recv_buffer = NULL;
beam->recv_pool = NULL;
}
if (safe_send && beam->send_pool) {
pool_kill(beam, beam->send_pool, beam_send_cleanup);
status = beam_send_cleanup(beam);
}
if (safe_recv) {
ap_assert(H2_BPROXY_LIST_EMPTY(&beam->proxies));
ap_assert(H2_BLIST_EMPTY(&beam->send_list));
ap_assert(H2_BLIST_EMPTY(&beam->hold_list));
ap_assert(H2_BLIST_EMPTY(&beam->purge_list));
}
return status;
}
static apr_status_t beam_pool_cleanup(void *data)
{
return beam_cleanup(data, 1);
}
apr_status_t h2_beam_destroy(h2_bucket_beam *beam)
{
apr_pool_cleanup_kill(beam->pool, beam, beam_pool_cleanup);
return beam_cleanup(beam, 0);
}
apr_status_t h2_beam_create(h2_bucket_beam **pbeam, apr_pool_t *pool,
int id, const char *tag,
h2_beam_owner_t owner,
apr_size_t max_buf_size,
apr_interval_time_t timeout)
{
h2_bucket_beam *beam;
apr_status_t rv = APR_SUCCESS;
beam = apr_pcalloc(pool, sizeof(*beam));
if (!beam) {
return APR_ENOMEM;
}
beam->id = id;
beam->tag = tag;
beam->pool = pool;
beam->owner = owner;
H2_BLIST_INIT(&beam->send_list);
H2_BLIST_INIT(&beam->hold_list);
H2_BLIST_INIT(&beam->purge_list);
H2_BPROXY_LIST_INIT(&beam->proxies);
beam->tx_mem_limits = 1;
beam->max_buf_size = max_buf_size;
beam->timeout = timeout;
rv = apr_thread_mutex_create(&beam->lock, APR_THREAD_MUTEX_DEFAULT, pool);
if (APR_SUCCESS == rv) {
rv = apr_thread_cond_create(&beam->change, pool);
if (APR_SUCCESS == rv) {
apr_pool_pre_cleanup_register(pool, beam, beam_pool_cleanup);
*pbeam = beam;
}
}
return rv;
}
void h2_beam_buffer_size_set(h2_bucket_beam *beam, apr_size_t buffer_size)
{
h2_beam_lock bl;
if (enter_yellow(beam, &bl) == APR_SUCCESS) {
beam->max_buf_size = buffer_size;
leave_yellow(beam, &bl);
}
}
apr_size_t h2_beam_buffer_size_get(h2_bucket_beam *beam)
{
h2_beam_lock bl;
apr_size_t buffer_size = 0;
if (beam && enter_yellow(beam, &bl) == APR_SUCCESS) {
buffer_size = beam->max_buf_size;
leave_yellow(beam, &bl);
}
return buffer_size;
}
void h2_beam_timeout_set(h2_bucket_beam *beam, apr_interval_time_t timeout)
{
h2_beam_lock bl;
if (enter_yellow(beam, &bl) == APR_SUCCESS) {
beam->timeout = timeout;
leave_yellow(beam, &bl);
}
}
apr_interval_time_t h2_beam_timeout_get(h2_bucket_beam *beam)
{
h2_beam_lock bl;
apr_interval_time_t timeout = 0;
if (enter_yellow(beam, &bl) == APR_SUCCESS) {
timeout = beam->timeout;
leave_yellow(beam, &bl);
}
return timeout;
}
void h2_beam_abort(h2_bucket_beam *beam)
{
h2_beam_lock bl;
if (beam && enter_yellow(beam, &bl) == APR_SUCCESS) {
beam->aborted = 1;
r_purge_sent(beam);
h2_blist_cleanup(&beam->send_list);
report_consumption(beam, &bl);
apr_thread_cond_broadcast(beam->change);
leave_yellow(beam, &bl);
}
}
apr_status_t h2_beam_close(h2_bucket_beam *beam)
{
h2_beam_lock bl;
if (beam && enter_yellow(beam, &bl) == APR_SUCCESS) {
r_purge_sent(beam);
beam_close(beam);
report_consumption(beam, &bl);
leave_yellow(beam, &bl);
}
return beam->aborted? APR_ECONNABORTED : APR_SUCCESS;
}
apr_status_t h2_beam_leave(h2_bucket_beam *beam)
{
h2_beam_lock bl;
if (beam && enter_yellow(beam, &bl) == APR_SUCCESS) {
recv_buffer_cleanup(beam, &bl);
beam->aborted = 1;
beam_close(beam);
leave_yellow(beam, &bl);
}
return APR_SUCCESS;
}
apr_status_t h2_beam_wait_empty(h2_bucket_beam *beam, apr_read_type_e block)
{
apr_status_t status;
h2_beam_lock bl;
if ((status = enter_yellow(beam, &bl)) == APR_SUCCESS) {
status = wait_empty(beam, block, bl.mutex);
leave_yellow(beam, &bl);
}
return status;
}
static void move_to_hold(h2_bucket_beam *beam,
apr_bucket_brigade *sender_bb)
{
apr_bucket *b;
while (sender_bb && !APR_BRIGADE_EMPTY(sender_bb)) {
b = APR_BRIGADE_FIRST(sender_bb);
APR_BUCKET_REMOVE(b);
H2_BLIST_INSERT_TAIL(&beam->send_list, b);
}
}
static apr_status_t append_bucket(h2_bucket_beam *beam,
apr_bucket *b,
apr_read_type_e block,
apr_size_t *pspace_left,
h2_beam_lock *pbl)
{
const char *data;
apr_size_t len;
apr_status_t status;
int can_beam = 0, check_len;
if (beam->aborted) {
return APR_ECONNABORTED;
}
if (APR_BUCKET_IS_METADATA(b)) {
if (APR_BUCKET_IS_EOS(b)) {
beam->closed = 1;
}
APR_BUCKET_REMOVE(b);
H2_BLIST_INSERT_TAIL(&beam->send_list, b);
return APR_SUCCESS;
}
else if (APR_BUCKET_IS_FILE(b)) {
/* For file buckets the problem is their internal readpool that
* is used on the first read to allocate buffer/mmap.
* Since setting aside a file bucket will de-register the
* file cleanup function from the previous pool, we need to
* call that only from the sender thread.
*
* Currently, we do not handle file bucket with refcount > 1 as
* the beam is then not in complete control of the file's lifetime.
* Which results in the bug that a file get closed by the receiver
* while the sender or the beam still have buckets using it.
*
* Additionally, we allow callbacks to prevent beaming file
* handles across. The use case for this is to limit the number
* of open file handles and rather use a less efficient beam
* transport. */
apr_bucket_file *bf = b->data;
apr_file_t *fd = bf->fd;
can_beam = (bf->refcount.refcount == 1);
if (can_beam && beam->can_beam_fn) {
can_beam = beam->can_beam_fn(beam->can_beam_ctx, beam, fd);
}
check_len = !can_beam;
}
else {
if (b->length == ((apr_size_t)-1)) {
const char *data;
status = apr_bucket_read(b, &data, &len, APR_BLOCK_READ);
if (status != APR_SUCCESS) {
return status;
}
}
check_len = 1;
}
if (check_len) {
if (b->length > *pspace_left) {
apr_bucket_split(b, *pspace_left);
}
*pspace_left -= b->length;
}
/* The fundamental problem is that reading a sender bucket from
* a receiver thread is a total NO GO, because the bucket might use
* its pool/bucket_alloc from a foreign thread and that will
* corrupt. */
status = APR_ENOTIMPL;
if (APR_BUCKET_IS_TRANSIENT(b)) {
/* this takes care of transient buckets and converts them
* into heap ones. Other bucket types might or might not be
* affected by this. */
status = apr_bucket_setaside(b, beam->send_pool);
}
else if (APR_BUCKET_IS_HEAP(b)) {
/* For heap buckets read from a receiver thread is fine. The
* data will be there and live until the bucket itself is
* destroyed. */
status = APR_SUCCESS;
}
else if (APR_BUCKET_IS_POOL(b)) {
/* pool buckets are bastards that register at pool cleanup
* to morph themselves into heap buckets. That may happen anytime,
* even after the bucket data pointer has been read. So at
* any time inside the receiver thread, the pool bucket memory
* may disappear. yikes. */
status = apr_bucket_read(b, &data, &len, APR_BLOCK_READ);
if (status == APR_SUCCESS) {
apr_bucket_heap_make(b, data, len, NULL);
}
}
else if (APR_BUCKET_IS_FILE(b) && can_beam) {
status = apr_bucket_setaside(b, beam->send_pool);
}
if (status == APR_ENOTIMPL) {
/* we have no knowledge about the internals of this bucket,
* but hope that after read, its data stays immutable for the
* lifetime of the bucket. (see pool bucket handling above for
* a counter example).
* We do the read while in the sender thread, so that the bucket may
* use pools/allocators safely. */
status = apr_bucket_read(b, &data, &len, APR_BLOCK_READ);
if (status == APR_SUCCESS) {
status = apr_bucket_setaside(b, beam->send_pool);
}
}
if (status != APR_SUCCESS && status != APR_ENOTIMPL) {
return status;
}
APR_BUCKET_REMOVE(b);
H2_BLIST_INSERT_TAIL(&beam->send_list, b);
beam->sent_bytes += b->length;
return APR_SUCCESS;
}
void h2_beam_send_from(h2_bucket_beam *beam, apr_pool_t *p)
{
h2_beam_lock bl;
/* Called from the sender thread to add buckets to the beam */
if (enter_yellow(beam, &bl) == APR_SUCCESS) {
r_purge_sent(beam);
beam_set_send_pool(beam, p);
leave_yellow(beam, &bl);
}
}
apr_status_t h2_beam_send(h2_bucket_beam *beam,
apr_bucket_brigade *sender_bb,
apr_read_type_e block)
{
apr_bucket *b;
apr_status_t rv = APR_SUCCESS;
apr_size_t space_left = 0;
h2_beam_lock bl;
/* Called from the sender thread to add buckets to the beam */
if (enter_yellow(beam, &bl) == APR_SUCCESS) {
ap_assert(beam->send_pool);
r_purge_sent(beam);
if (beam->aborted) {
move_to_hold(beam, sender_bb);
rv = APR_ECONNABORTED;
}
else if (sender_bb) {
int force_report = !APR_BRIGADE_EMPTY(sender_bb);
space_left = calc_space_left(beam);
while (!APR_BRIGADE_EMPTY(sender_bb) && APR_SUCCESS == rv) {
if (space_left <= 0) {
report_prod_io(beam, force_report, &bl);
r_purge_sent(beam);
rv = wait_not_full(beam, block, &space_left, &bl);
if (APR_SUCCESS != rv) {
break;
}
}
b = APR_BRIGADE_FIRST(sender_bb);
rv = append_bucket(beam, b, block, &space_left, &bl);
}
report_prod_io(beam, force_report, &bl);
apr_thread_cond_broadcast(beam->change);
}
report_consumption(beam, &bl);
leave_yellow(beam, &bl);
}
return rv;
}
apr_status_t h2_beam_receive(h2_bucket_beam *beam,
apr_bucket_brigade *bb,
apr_read_type_e block,
apr_off_t readbytes)
{
h2_beam_lock bl;
apr_bucket *bsender, *brecv, *ng;
int transferred = 0;
apr_status_t status = APR_SUCCESS;
apr_off_t remain;
int transferred_buckets = 0;
/* Called from the receiver thread to take buckets from the beam */
if (enter_yellow(beam, &bl) == APR_SUCCESS) {
if (readbytes <= 0) {
readbytes = APR_SIZE_MAX;
}
remain = readbytes;
transfer:
if (beam->aborted) {
recv_buffer_cleanup(beam, &bl);
status = APR_ECONNABORTED;
goto leave;
}
/* transfer enough buckets from our receiver brigade, if we have one */
while (remain >= 0
&& beam->recv_buffer
&& !APR_BRIGADE_EMPTY(beam->recv_buffer)) {
brecv = APR_BRIGADE_FIRST(beam->recv_buffer);
if (brecv->length > 0 && remain <= 0) {
break;
}
APR_BUCKET_REMOVE(brecv);
APR_BRIGADE_INSERT_TAIL(bb, brecv);
remain -= brecv->length;
++transferred;
}
/* transfer from our sender brigade, transforming sender buckets to
* receiver ones until we have enough */
while (remain >= 0 && !H2_BLIST_EMPTY(&beam->send_list)) {
brecv = NULL;
bsender = H2_BLIST_FIRST(&beam->send_list);
if (bsender->length > 0 && remain <= 0) {
break;
}
if (APR_BUCKET_IS_METADATA(bsender)) {
if (APR_BUCKET_IS_EOS(bsender)) {
brecv = apr_bucket_eos_create(bb->bucket_alloc);
beam->close_sent = 1;
}
else if (APR_BUCKET_IS_FLUSH(bsender)) {
brecv = apr_bucket_flush_create(bb->bucket_alloc);
}
else if (AP_BUCKET_IS_ERROR(bsender)) {
ap_bucket_error *eb = (ap_bucket_error *)bsender;
brecv = ap_bucket_error_create(eb->status, eb->data,
bb->p, bb->bucket_alloc);
}
}
else if (bsender->length == 0) {
APR_BUCKET_REMOVE(bsender);
H2_BLIST_INSERT_TAIL(&beam->hold_list, bsender);
continue;
}
else if (APR_BUCKET_IS_FILE(bsender)) {
/* This is set aside into the target brigade pool so that
* any read operation messes with that pool and not
* the sender one. */
apr_bucket_file *f = (apr_bucket_file *)bsender->data;
apr_file_t *fd = f->fd;
int setaside = (f->readpool != bb->p);
if (setaside) {
status = apr_file_setaside(&fd, fd, bb->p);
if (status != APR_SUCCESS) {
goto leave;
}
++beam->files_beamed;
}
ng = apr_brigade_insert_file(bb, fd, bsender->start, bsender->length,
bb->p);
#if APR_HAS_MMAP
/* disable mmap handling as this leads to segfaults when
* the underlying file is changed while memory pointer has
* been handed out. See also PR 59348 */
apr_bucket_file_enable_mmap(ng, 0);
#endif
APR_BUCKET_REMOVE(bsender);
H2_BLIST_INSERT_TAIL(&beam->hold_list, bsender);
remain -= bsender->length;
++transferred;
++transferred_buckets;
continue;
}
else {
/* create a "receiver" standin bucket. we took care about the
* underlying sender bucket and its data when we placed it into
* the sender brigade.
* the beam bucket will notify us on destruction that bsender is
* no longer needed. */
brecv = h2_beam_bucket_create(beam, bsender, bb->bucket_alloc,
beam->buckets_sent++);
}
/* Place the sender bucket into our hold, to be destroyed when no
* receiver bucket references it any more. */
APR_BUCKET_REMOVE(bsender);
H2_BLIST_INSERT_TAIL(&beam->hold_list, bsender);
beam->received_bytes += bsender->length;
++transferred_buckets;
if (brecv) {
APR_BRIGADE_INSERT_TAIL(bb, brecv);
remain -= brecv->length;
++transferred;
}
else {
/* let outside hook determine how bucket is beamed */
leave_yellow(beam, &bl);
brecv = h2_beam_bucket(beam, bb, bsender);
enter_yellow(beam, &bl);
while (brecv && brecv != APR_BRIGADE_SENTINEL(bb)) {
++transferred;
remain -= brecv->length;
brecv = APR_BUCKET_NEXT(brecv);
}
}
}
if (remain < 0) {
/* too much, put some back into out recv_buffer */
remain = readbytes;
for (brecv = APR_BRIGADE_FIRST(bb);
brecv != APR_BRIGADE_SENTINEL(bb);
brecv = APR_BUCKET_NEXT(brecv)) {
remain -= (beam->tx_mem_limits? bucket_mem_used(brecv)
: brecv->length);
if (remain < 0) {
apr_bucket_split(brecv, brecv->length+remain);
beam->recv_buffer = apr_brigade_split_ex(bb,
APR_BUCKET_NEXT(brecv),
beam->recv_buffer);
break;
}
}
}
if (beam->closed && buffer_is_empty(beam)) {
/* beam is closed and we have nothing more to receive */
if (!beam->close_sent) {
apr_bucket *b = apr_bucket_eos_create(bb->bucket_alloc);
APR_BRIGADE_INSERT_TAIL(bb, b);
beam->close_sent = 1;
++transferred;
status = APR_SUCCESS;
}
}
if (transferred_buckets > 0) {
if (beam->cons_ev_cb) {
beam->cons_ev_cb(beam->cons_ctx, beam);
}
}
if (transferred) {
apr_thread_cond_broadcast(beam->change);
status = APR_SUCCESS;
}
else {
status = wait_not_empty(beam, block, bl.mutex);
if (status != APR_SUCCESS) {
goto leave;
}
goto transfer;
}
leave:
leave_yellow(beam, &bl);
}
return status;
}
void h2_beam_on_consumed(h2_bucket_beam *beam,
h2_beam_ev_callback *ev_cb,
h2_beam_io_callback *io_cb, void *ctx)
{
h2_beam_lock bl;
if (enter_yellow(beam, &bl) == APR_SUCCESS) {
beam->cons_ev_cb = ev_cb;
beam->cons_io_cb = io_cb;
beam->cons_ctx = ctx;
leave_yellow(beam, &bl);
}
}
void h2_beam_on_produced(h2_bucket_beam *beam,
h2_beam_io_callback *io_cb, void *ctx)
{
h2_beam_lock bl;
if (enter_yellow(beam, &bl) == APR_SUCCESS) {
beam->prod_io_cb = io_cb;
beam->prod_ctx = ctx;
leave_yellow(beam, &bl);
}
}
void h2_beam_on_file_beam(h2_bucket_beam *beam,
h2_beam_can_beam_callback *cb, void *ctx)
{
h2_beam_lock bl;
if (enter_yellow(beam, &bl) == APR_SUCCESS) {
beam->can_beam_fn = cb;
beam->can_beam_ctx = ctx;
leave_yellow(beam, &bl);
}
}
apr_off_t h2_beam_get_buffered(h2_bucket_beam *beam)
{
apr_bucket *b;
apr_off_t l = 0;
h2_beam_lock bl;
if (beam && enter_yellow(beam, &bl) == APR_SUCCESS) {
for (b = H2_BLIST_FIRST(&beam->send_list);
b != H2_BLIST_SENTINEL(&beam->send_list);
b = APR_BUCKET_NEXT(b)) {
/* should all have determinate length */
l += b->length;
}
leave_yellow(beam, &bl);
}
return l;
}
apr_off_t h2_beam_get_mem_used(h2_bucket_beam *beam)
{
apr_bucket *b;
apr_off_t l = 0;
h2_beam_lock bl;
if (beam && enter_yellow(beam, &bl) == APR_SUCCESS) {
for (b = H2_BLIST_FIRST(&beam->send_list);
b != H2_BLIST_SENTINEL(&beam->send_list);
b = APR_BUCKET_NEXT(b)) {
l += bucket_mem_used(b);
}
leave_yellow(beam, &bl);
}
return l;
}
int h2_beam_empty(h2_bucket_beam *beam)
{
int empty = 1;
h2_beam_lock bl;
if (beam && enter_yellow(beam, &bl) == APR_SUCCESS) {
empty = (H2_BLIST_EMPTY(&beam->send_list)
&& (!beam->recv_buffer || APR_BRIGADE_EMPTY(beam->recv_buffer)));
leave_yellow(beam, &bl);
}
return empty;
}
int h2_beam_holds_proxies(h2_bucket_beam *beam)
{
int has_proxies = 1;
h2_beam_lock bl;
if (beam && enter_yellow(beam, &bl) == APR_SUCCESS) {
has_proxies = !H2_BPROXY_LIST_EMPTY(&beam->proxies);
leave_yellow(beam, &bl);
}
return has_proxies;
}
int h2_beam_was_received(h2_bucket_beam *beam)
{
int happend = 0;
h2_beam_lock bl;
if (beam && enter_yellow(beam, &bl) == APR_SUCCESS) {
happend = (beam->received_bytes > 0);
leave_yellow(beam, &bl);
}
return happend;
}
apr_size_t h2_beam_get_files_beamed(h2_bucket_beam *beam)
{
apr_size_t n = 0;
h2_beam_lock bl;
if (beam && enter_yellow(beam, &bl) == APR_SUCCESS) {
n = beam->files_beamed;
leave_yellow(beam, &bl);
}
return n;
}
int h2_beam_no_files(void *ctx, h2_bucket_beam *beam, apr_file_t *file)
{
return 0;
}
int h2_beam_report_consumption(h2_bucket_beam *beam)
{
h2_beam_lock bl;
int rv = 0;
if (enter_yellow(beam, &bl) == APR_SUCCESS) {
rv = report_consumption(beam, &bl);
leave_yellow(beam, &bl);
}
return rv;
}
void h2_beam_log(h2_bucket_beam *beam, conn_rec *c, int level, const char *msg)
{
if (beam && APLOG_C_IS_LEVEL(c,level)) {
ap_log_cerror(APLOG_MARK, level, 0, c,
"beam(%ld-%d,%s,closed=%d,aborted=%d,empty=%d,buf=%ld): %s",
(c->master? c->master->id : c->id), beam->id, beam->tag,
beam->closed, beam->aborted, h2_beam_empty(beam),
(long)h2_beam_get_buffered(beam), msg);
}
}