Previously, after sending a header we always sent a last buffer and
finalized a request with code 0, even in case of errors. In some cases
this resulted in a loss of ability to detect the response wasn't complete
(e.g. if Content-Length was removed from a response by gzip filter).
This change tries to propogate to a client information that a response
isn't complete in such cases. In particular, with this change we no longer
pretend a returned response is complete if we wasn't able to create
a temporary file.
If an error code suggests the error wasn't fatal, we flush buffered data
and disable keepalive, then finalize request normally. This allows to to
propogate information about a problem to a client, while still sending all
the data we've got from an upstream.
No semantic changes expected, though some checks are done differently.
In particular, the r->cached flag is no longer explicitly checked. Instead,
we relay on u->header_sent not being set if a response is sent from
a cache.
The NGX_HTTP_CLIENT_CLOSED_REQUEST code is allowed to happen after we
started sending a response (much like NGX_HTTP_REQUEST_TIME_OUT), so there
is no need to reset response code to 0 in this case.
Checks were added to both buffered and unbuffered code paths to detect
and complain if a response is incomplete. Appropriate error codes are
now passed to ngx_http_upstream_finalize_request().
With this change in unbuffered mode we now use u->length set to -1 as an
indicator that EOF is allowed per protocol and used to indicate response
end (much like its with p->length in buffered mode). Proxy module was
changed to set u->length to 1 (instead of previously used -1) in case of
chunked transfer encoding used to comply with the above.
That is, by default we assume that response end is signalled by
a connection close. This seems to be better default, and in line
with u->pipe->length behaviour.
Memcached module was modified accordingly.
In case of upstream eof, only responses with u->pipe->length == -1
are now cached/stored. This ensures that unfinished chunked responses
are not cached.
Note well - previously used checks for u->headers_in.content_length_n are
preserved. This provides an additional level of protection if protol data
disagree with Content-Length header provided (e.g., a FastCGI response
is sent with wrong Content-Length, or an incomple SCGI or uwsgi response),
as well as protects from storing of responses to HEAD requests. This should
be reconsidered if we'll consider caching of responses to HEAD requests.
There is no real difference from previously used 0 as NGX_HTTP_* will
become 0 in ngx_http_upstream_finalize_request(), but the change
preserves information about a timeout a bit longer. Previous use of
ETIMEDOUT in one place was just wrong.
Note well that with cacheable responses there will be a difference
(code in ngx_http_upstream_finalize_request() will store the error
in cache), though this change doesn't touch cacheable case.
Previously, ngx_http_upstream_finalize_request(0) was used in most
cases after errors. While with current code there is no difference,
use of NGX_ERROR allows to pass a bit more information into
ngx_http_upstream_finalize_request().
In all cases ngx_http_upstream_finalize_request() with NGX_ERROR now used.
Previously used NGX_HTTP_INTERNAL_SERVER_ERROR in the subrequest in memory
case don't cause any harm, but inconsistent with other uses.
Previous code called ngx_http_finalize_request() with rc = 0. This is
ok if a response status was already set, but resulted in "000" being
logged if it wasn't. In particular this happened with limit_req
if a connection was prematurely closed during limit_req delay.
After a failed partial match we now check if there is another partial
match in previously matched substring to fix cases like "aab" in "aaab".
The ctx->saved string is now always sent if it's present on return
from the ngx_http_sub_parse() function (and reset accordingly). This
allows to release parts of previously matched data.
If a pattern was partially matched at a response end, partially matched
string wasn't send. E.g., a response "fo" was truncated to an empty response
if partially mathed by a pattern "foo".
It is possible to send FLAG_FIN in additional empty data frame, even if it is
known from the content-length header that request body is empty. And Firefox
actually behaves like this (see ticket #357).
To simplify code we sacrificed our microoptimization that did not work right
due to missing check in the ngx_http_spdy_state_data() function for rb->buf
set to NULL.
The exsltRegisterAll() needs to be called before XSLT stylesheets
are compiled, else stylesheet compilation hooks will not work. This
change fixes EXSLT Functions extension.
On Linux, sockaddr length is required to process unix socket addresses properly
due to unnamed sockets (which don't have sun_path set at all) and abstract
namespace sockets.
Minimal data length we expect for further calls was calculated incorrectly
if parsing stopped right after parsing chunk size. This might in theory
affect clients and/or backends using LF instead of CRLF.
Patch by Dmitry Popov.
When several "error_log" directives are specified in the same configuration
block, logs are written to all files with a matching log level.
All logs are stored in the singly-linked list that is sorted by log level in
the descending order.
Specific debug levels (NGX_LOG_DEBUG_HTTP,EVENT, etc.) are not supported
if several "error_log" directives are specified. In this case all logs
will use debug level that has largest absolute value.
Valgrind complains if we pass uninitialized memory to a syscall:
==36492== Syscall param sendmsg(msg.msg_iov[0]) points to uninitialised byte(s)
==36492== at 0x6B5E6A: sendmsg (in /usr/lib/system/libsystem_kernel.dylib)
==36492== by 0x10004288E: ngx_signal_worker_processes (ngx_process_cycle.c:527)
==36492== by 0x1000417A7: ngx_master_process_cycle (ngx_process_cycle.c:203)
==36492== by 0x100001F10: main (nginx.c:410)
==36492== Address 0x7fff5fbff71c is on thread 1's stack
Even initialization of all members of the structure passed isn't enough, as
there is padding which still remains uninitialized and results in Valgrind
complaint. Note there is no real problem here as data from uninitialized
memory isn't used.
If "stderr" was specified in one of the "error_log" directives,
stderr is not redirected to the first error_log on startup,
configuration reload, and reopening log files.
The parameter is mostly identical to http_404, and is expected to
be used in similar situations. The 403 code might be returned by
a backend instead of 404 on initial sync of new directories with rsync.
See here for feature request and additional details:
http://mailman.nginx.org/pipermail/nginx-ru/2013-April/050920.html
An invalid memcached reply that started with '\n' could cause
segmentation fault.
An invalid memcached reply "VALUE / 0 2\r?ok\r\nEND\r\n" was
considered as a valid response.
In addition, if memcached reports that the key was not found,
set u->headers_in.content_length_n to 0. This ensures that
ngx_http_memcached_filter() will not be called while previous
code relied on always intercepting 404. Initialization of
ctx->rest was moved to where it belongs.
Due to peer->checked always set since rev. c90801720a0c (1.3.0)
by round-robin and least_conn balancers (ip_hash not affected),
the code in ngx_http_upstream_free_round_robin_peer() function
incorrectly reset peer->fails too often.
Reported by Dmitry Popov,
http://mailman.nginx.org/pipermail/nginx-devel/2013-May/003720.html
There are two significant changes in this patch:
1) The <= 0 comparison is done with a signed type. This fixes the case
of ngx_time() being larger than r->lingering_time.
2) Calculation of r->lingering_time - ngx_time() is now always done
in the ngx_msec_t type. This ensures the calculation is correct
even if time_t is unsigned and differs in size from ngx_msec_t.
Thanks to Lanshun Zhou.
