apr_status_t ap_core_output_filter(ap_filter_t *f, apr_bucket_brigade *b)
{
apr_status_t rv;
apr_bucket_brigade *more;
conn_rec *c = f->c;
core_net_rec *net = f->ctx;
core_output_filter_ctx_t *ctx = net->out_ctx;
apr_read_type_e eblock = APR_NONBLOCK_READ;
apr_pool_t *input_pool = b->p;
/* Fail quickly if the connection has already been aborted. */
if (c->aborted) {
apr_brigade_cleanup(b);
return APR_ECONNABORTED;
}
if (ctx == NULL) {
ctx = apr_pcalloc(c->pool, sizeof(*ctx));
net->out_ctx = ctx;
}
/* If we have a saved brigade, concatenate the new brigade to it */
if (ctx->b) {
APR_BRIGADE_CONCAT(ctx->b, b);
b = ctx->b;
ctx->b = NULL;
}
/* Perform multiple passes over the brigade, sending batches of output
to the connection. */
while (b && !APR_BRIGADE_EMPTY(b)) {
apr_size_t nbytes = 0;
apr_bucket *last_e = NULL; /* initialized for debugging */
apr_bucket *e;
/* one group of iovecs per pass over the brigade */
apr_size_t nvec = 0;
apr_size_t nvec_trailers = 0;
struct iovec vec[MAX_IOVEC_TO_WRITE];
struct iovec vec_trailers[MAX_IOVEC_TO_WRITE];
/* one file per pass over the brigade */
apr_file_t *fd = NULL;
apr_size_t flen = 0;
apr_off_t foffset = 0;
/* keep track of buckets that we've concatenated
* to avoid small writes
*/
apr_bucket *last_merged_bucket = NULL;
/* tail of brigade if we need another pass */
more = NULL;
/* Iterate over the brigade: collect iovecs and/or a file */
for (e = APR_BRIGADE_FIRST(b);
e != APR_BRIGADE_SENTINEL(b);
e = APR_BUCKET_NEXT(e))
{
/* keep track of the last bucket processed */
last_e = e;
if (APR_BUCKET_IS_EOS(e) || AP_BUCKET_IS_EOC(e)) {
break;
}
else if (APR_BUCKET_IS_FLUSH(e)) {
if (e != APR_BRIGADE_LAST(b)) {
more = apr_brigade_split(b, APR_BUCKET_NEXT(e));
}
break;
}
/* It doesn't make any sense to use sendfile for a file bucket
* that represents 10 bytes.
*/
else if (APR_BUCKET_IS_FILE(e)
&& (e->length >= AP_MIN_SENDFILE_BYTES)) {
apr_bucket_file *a = e->data;
/* We can't handle more than one file bucket at a time
* so we split here and send the file we have already
* found.
*/
if (fd) {
more = apr_brigade_split(b, e);
break;
}
fd = a->fd;
flen = e->length;
foffset = e->start;
}
else {
const char *str;
apr_size_t n;
rv = apr_bucket_read(e, &str, &n, eblock);
if (APR_STATUS_IS_EAGAIN(rv)) {
/* send what we have so far since we shouldn't expect more
* output for a while... next time we read, block
*/
more = apr_brigade_split(b, e);
eblock = APR_BLOCK_READ;
break;
}
eblock = APR_NONBLOCK_READ;
if (n) {
if (!fd) {
if (nvec == MAX_IOVEC_TO_WRITE) {
/* woah! too many. buffer them up, for use later. */
apr_bucket *temp, *next;
apr_bucket_brigade *temp_brig;
if (nbytes >= AP_MIN_BYTES_TO_WRITE) {
/* We have enough data in the iovec
* to justify doing a writev
*/
more = apr_brigade_split(b, e);
break;
}
/* Create a temporary brigade as a means
* of concatenating a bunch of buckets together
*/
temp_brig = apr_brigade_create(f->c->pool,
f->c->bucket_alloc);
if (last_merged_bucket) {
/* If we've concatenated together small
* buckets already in a previous pass,
* the initial buckets in this brigade
* are heap buckets that may have extra
* space left in them (because they
* were created by apr_brigade_write()).
* We can take advantage of this by
* building the new temp brigade out of
* these buckets, so that the content
* in them doesn't have to be copied again.
*/
APR_BRIGADE_PREPEND(b, temp_brig);
brigade_move(temp_brig, b, APR_BUCKET_NEXT(last_merged_bucket));
}
temp = APR_BRIGADE_FIRST(b);
while (temp != e) {
apr_bucket *d;
rv = apr_bucket_read(temp, &str, &n, APR_BLOCK_READ);
apr_brigade_write(temp_brig, NULL, NULL, str, n);
d = temp;
temp = APR_BUCKET_NEXT(temp);
apr_bucket_delete(d);
}
nvec = 0;
nbytes = 0;
temp = APR_BRIGADE_FIRST(temp_brig);
APR_BUCKET_REMOVE(temp);
APR_BRIGADE_INSERT_HEAD(b, temp);
apr_bucket_read(temp, &str, &n, APR_BLOCK_READ);
vec[nvec].iov_base = (char*) str;
vec[nvec].iov_len = n;
nvec++;
/* Just in case the temporary brigade has
* multiple buckets, recover the rest of
* them and put them in the brigade that
* we're sending.
*/
for (next = APR_BRIGADE_FIRST(temp_brig);
next != APR_BRIGADE_SENTINEL(temp_brig);
next = APR_BRIGADE_FIRST(temp_brig)) {
APR_BUCKET_REMOVE(next);
APR_BUCKET_INSERT_AFTER(temp, next);
temp = next;
apr_bucket_read(next, &str, &n,
APR_BLOCK_READ);
vec[nvec].iov_base = (char*) str;
vec[nvec].iov_len = n;
nvec++;
}
apr_brigade_destroy(temp_brig);
last_merged_bucket = temp;
e = temp;
last_e = e;
}
else {
vec[nvec].iov_base = (char*) str;
vec[nvec].iov_len = n;
nvec++;
}
}
else {
/* The bucket is a trailer to a file bucket */
if (nvec_trailers == MAX_IOVEC_TO_WRITE) {
/* woah! too many. stop now. */
more = apr_brigade_split(b, e);
break;
}
vec_trailers[nvec_trailers].iov_base = (char*) str;
vec_trailers[nvec_trailers].iov_len = n;
nvec_trailers++;
}
nbytes += n;
}
}
}
/* Completed iterating over the brigade, now determine if we want
* to buffer the brigade or send the brigade out on the network.
*
* Save if we haven't accumulated enough bytes to send, the connection
* is not about to be closed, and:
*
* 1) we didn't see a file, we don't have more passes over the
* brigade to perform, AND we didn't stop at a FLUSH bucket.
* (IOW, we will save plain old bytes such as HTTP headers)
* or
* 2) we hit the EOS and have a keep-alive connection
* (IOW, this response is a bit more complex, but we save it
* with the hope of concatenating with another response)
*/
if (nbytes + flen < AP_MIN_BYTES_TO_WRITE
&& !AP_BUCKET_IS_EOC(last_e)
&& ((!fd && !more && !APR_BUCKET_IS_FLUSH(last_e))
|| (APR_BUCKET_IS_EOS(last_e)
&& c->keepalive == AP_CONN_KEEPALIVE))) {
/* NEVER save an EOS in here. If we are saving a brigade with
* an EOS bucket, then we are doing keepalive connections, and
* we want to process to second request fully.
*/
if (APR_BUCKET_IS_EOS(last_e)) {
apr_bucket *bucket;
int file_bucket_saved = 0;
apr_bucket_delete(last_e);
for (bucket = APR_BRIGADE_FIRST(b);
bucket != APR_BRIGADE_SENTINEL(b);
bucket = APR_BUCKET_NEXT(bucket)) {
/* Do a read on each bucket to pull in the
* data from pipe and socket buckets, so
* that we don't leave their file descriptors
* open indefinitely. Do the same for file
* buckets, with one exception: allow the
* first file bucket in the brigade to remain
* a file bucket, so that we don't end up
* doing an mmap+memcpy every time a client
* requests a <8KB file over a keepalive
* connection.
*/
if (APR_BUCKET_IS_FILE(bucket) && !file_bucket_saved) {
file_bucket_saved = 1;
}
else {
const char *buf;
apr_size_t len = 0;
rv = apr_bucket_read(bucket, &buf, &len,
APR_BLOCK_READ);
if (rv != APR_SUCCESS) {
ap_log_cerror(APLOG_MARK, APLOG_ERR, rv,
c, "core_output_filter:"
" Error reading from bucket.");
return HTTP_INTERNAL_SERVER_ERROR;
}
}
}
}
if (!ctx->deferred_write_pool) {
apr_pool_create(&ctx->deferred_write_pool, c->pool);
apr_pool_tag(ctx->deferred_write_pool, "deferred_write");
}
ap_save_brigade(f, &ctx->b, &b, ctx->deferred_write_pool);
return APR_SUCCESS;
}
if (fd) {
apr_hdtr_t hdtr;
apr_size_t bytes_sent;
#if APR_HAS_SENDFILE
apr_int32_t flags = 0;
#endif
memset(&hdtr, '\0', sizeof(hdtr));
if (nvec) {
hdtr.numheaders = nvec;
hdtr.headers = vec;
}
if (nvec_trailers) {
hdtr.numtrailers = nvec_trailers;
hdtr.trailers = vec_trailers;
}
#if APR_HAS_SENDFILE
if (apr_file_flags_get(fd) & APR_SENDFILE_ENABLED) {
if (c->keepalive == AP_CONN_CLOSE && APR_BUCKET_IS_EOS(last_e)) {
/* Prepare the socket to be reused */
flags |= APR_SENDFILE_DISCONNECT_SOCKET;
}
rv = sendfile_it_all(net, /* the network information */
fd, /* the file to send */
&hdtr, /* header and trailer iovecs */
foffset, /* offset in the file to begin
sending from */
flen, /* length of file */
nbytes + flen, /* total length including
headers */
&bytes_sent, /* how many bytes were
sent */
flags); /* apr_sendfile flags */
}
else
#endif
{
rv = emulate_sendfile(net, fd, &hdtr, foffset, flen,
&bytes_sent);
}
if (logio_add_bytes_out && bytes_sent > 0)
logio_add_bytes_out(c, bytes_sent);
fd = NULL;
}
else {
apr_size_t bytes_sent;
rv = writev_it_all(net->client_socket,
vec, nvec,
nbytes, &bytes_sent);
if (logio_add_bytes_out && bytes_sent > 0)
logio_add_bytes_out(c, bytes_sent);
}
apr_brigade_cleanup(b);
/* drive cleanups for resources which were set aside
* this may occur before or after termination of the request which
* created the resource
*/
if (ctx->deferred_write_pool) {
if (more && more->p == ctx->deferred_write_pool) {
/* "more" belongs to the deferred_write_pool,
* which is about to be cleared.
*/
if (APR_BRIGADE_EMPTY(more)) {
more = NULL;
}
else {
/* uh oh... change more's lifetime
* to the input brigade's lifetime
*/
apr_bucket_brigade *tmp_more = more;
more = NULL;
ap_save_brigade(f, &more, &tmp_more, input_pool);
}
}
apr_pool_clear(ctx->deferred_write_pool);
}
if (rv != APR_SUCCESS) {
ap_log_cerror(APLOG_MARK, APLOG_INFO, rv, c,
"core_output_filter: writing data to the network");
if (more)
apr_brigade_cleanup(more);
/* No need to check for SUCCESS, we did that above. */
if (!APR_STATUS_IS_EAGAIN(rv)) {
c->aborted = 1;
return APR_ECONNABORTED;
}
return APR_SUCCESS;
}
b = more;
more = NULL;
} /* end while () */
return APR_SUCCESS;
}
apr_status_t mgs_filter_output(ap_filter_t * f, apr_bucket_brigade * bb) {
apr_size_t ret;
mgs_handle_t *ctxt = (mgs_handle_t *) f->ctx;
apr_status_t status = APR_SUCCESS;
apr_read_type_e rblock = APR_NONBLOCK_READ;
if (f->c->aborted) {
apr_brigade_cleanup(bb);
return APR_ECONNABORTED;
}
if (ctxt->status == 0) {
gnutls_do_handshake(ctxt);
}
if (ctxt->status < 0) {
return ap_pass_brigade(f->next, bb);
}
while (!APR_BRIGADE_EMPTY(bb)) {
apr_bucket *bucket = APR_BRIGADE_FIRST(bb);
if (APR_BUCKET_IS_EOS(bucket)) {
return ap_pass_brigade(f->next, bb);
} else if (APR_BUCKET_IS_FLUSH(bucket)) {
/* Try Flush */
if (write_flush(ctxt) < 0) {
/* Flush Error */
return ctxt->output_rc;
}
/* cleanup! */
apr_bucket_delete(bucket);
} else if (AP_BUCKET_IS_EOC(bucket)) {
/* End Of Connection */
if (ctxt->session != NULL) {
/* Try A Clean Shutdown */
do {
ret = gnutls_bye(ctxt->session, GNUTLS_SHUT_WR);
} while (ret == GNUTLS_E_INTERRUPTED || ret == GNUTLS_E_AGAIN);
/* De-Initialize Session */
gnutls_deinit(ctxt->session);
ctxt->session = NULL;
}
/* cleanup! */
apr_bucket_delete(bucket);
/* Pass next brigade! */
return ap_pass_brigade(f->next, bb);
} else {
/* filter output */
const char *data;
apr_size_t len;
status = apr_bucket_read(bucket, &data, &len, rblock);
if (APR_STATUS_IS_EAGAIN(status)) {
/* No data available so Flush! */
if (write_flush(ctxt) < 0) {
return ctxt->output_rc;
}
/* Try again with a blocking read. */
rblock = APR_BLOCK_READ;
continue;
}
rblock = APR_NONBLOCK_READ;
if (!APR_STATUS_IS_EOF(status)
&& (status != APR_SUCCESS)) {
return status;
}
if (len > 0) {
if (ctxt->session == NULL) {
ret = GNUTLS_E_INVALID_REQUEST;
} else {
do {
ret =
gnutls_record_send
(ctxt->session, data,
len);
} while (ret == GNUTLS_E_INTERRUPTED
|| ret == GNUTLS_E_AGAIN);
}
if (ret < 0) {
/* error sending output */
ap_log_error(APLOG_MARK,
APLOG_INFO,
ctxt->output_rc,
ctxt->c->base_server,
"GnuTLS: Error writing data."
" (%d) '%s'",
(int) ret,
gnutls_strerror(ret));
if (ctxt->output_rc == APR_SUCCESS) {
ctxt->output_rc =
APR_EGENERAL;
return ctxt->output_rc;
}
} else if (ret != len) {
/* Not able to send the entire bucket,
split it and send it again. */
apr_bucket_split(bucket, ret);
}
}
apr_bucket_delete(bucket);
}
}
return status;
}
