optimize buffer_* primitives
Other than buffer_string_set_length(), reallocate with one power-2 step
in size (or use the requested size, if larger). This replaces the fixed
BUFFER_PIECE_SIZE round-up of only 64 bytes extension each reallocation,
which could lead to excessive reallocations in some scenarios.
buffer_extend() convenience routine to prep for batch append
(combines buffer_string_prepare_append() and buffer_commit())
mod_fastcgi, mod_scgi, mod_proxy and others now leverage buffer_extend()
mod_scgi directly performs little-endian encoding of short ints
http_response_write_header() optimizes writing response header,
leveraging buffer_extend()
modify mod_proxy to append line ends
similar to how it is done in http_response_write_header()
(removes one call to buffer_append_string_len())
RFC 7233 Range handling for all non-streaming responses,
including (non-streaming) dynamic responses
(previously Range responses handled only for static files)
(thx flynn)
When the backend sends Transfer-Encoding: chunked (which is HTTP/1.1,
not HTTP/1.0) and the client is HTTP/1.1, then lighttpd will transfer
the chunked encoding as it is sent from the backend without excess data
copying involved in decoding and then re-encoding. The bug is that if
the first data chunk (or chunks) is partially received at the same time
as the response headers, then the chunked encoding got corrupted.
x-ref:
"Socket errors after update to version 1.4.56"
https://redmine.lighttpd.net/issues/3044
use http_chunk_append_file_ref() and http_chunk_append_file_ref_range()
reduce resource usage (number of fds open) by reference counting open
fds to files served, and sharing the fd among FILE_CHUNKs in responses
relay 1xx from backend over HTTP/1.1, e.g. 103 Early Hints
(if client is connected using HTTP/1.1)
enabled by default unless disabled in lighttpd.conf with:
server.feature-flags += ( "server.h1-discard-backend-1xx" = "enable" )
Warning: backends which send 103 Early Hints should check User-Agent
before doing so since naive clients might not handle unexpected 1xx.
Some clients may take the 1xx response as the final response, expecting
only one response. Some clients might not properly handle 100 Continue
if the client did not send Expect: 100-continue with the request.
https://tools.ietf.org/html/rfc8297#section-3 Security Considerations
x-ref:
An HTTP Status Code for Indicating Hints (103 Early Hints)
https://tools.ietf.org/html/rfc8297
defer optimization to read small files into memory until after
response_start hooks have a chance to run, e.g. until after
mod_deflate chooses whether or not to serve file from compressed
cache, if deflate.cache-dir is configured
translate config server.modules "mod_compress" to "mod_deflate"
accept compress.* directives, but issue DEPRECATED warning trace
mod_deflate differences from mod_compress:
- mod_compress compress.filetype was exact match; deflate.mimetypes is
prefix match (behavior change might compress longer mimetype matches,
which are likely of similar type and compressability)
- mod_compress always sent entire (compressed) file for Range request
mod_deflate will stream compress range result (not stored in cache)
- mod_compress would short-circuit request with 403 Forbidden error
if request file did not exist (stat() failed) (This behavior was
unfriendly to other handlers)
- mod_compress compress.cache-dir layout differs from deflate.cache-dir
layout; file cache should be cleared (or renamed) when migrating from
mod_compress to mod_deflate
- mod_deflate does not issue Vary: Accept-Encoding if request does not
contain Accept-Encoding. The identity response can be cache by
proxies and served to clients. Historically, some proxies disabled
caching if any Vary: response was seen. If the Vary header is
desirable, mod_deflate code which checks for Accept-Encoding and
compression type can be moved down a few lines to be below the
setting of the Vary response header.
group HANDLER_COMEBACK logic in http_response_comeback() and call it
from places that reset state in order to (sometimes partially) reprocess
a request. This includes error handler (server.error-handler),
r->handler_module when cgi.local-redir, and looping in
http_response_prepare() when modules make changes to the request and
return HANDLER_COMEBACK (e.g. mod_rewrite, mod_magnet, mod_cml)
Also, set r->conditional_is_valid closer to where elements are set
(and become valid for use in condition checks), and parse target
in http_request_parse() instead of http_response_prepare()
NB: r->tmp_buf == srv->tmp_buf (pointer is copied for quicker access)
NB: request read and write chunkqueues currently point to connection
chunkqueues; per-request and per-connection chunkqueues are
not distinct from one another
con->read_queue == r->read_queue
con->write_queue == r->write_queue
NB: in the future, a separate connection config may be needed for
connection-level module hooks. Similarly, might need to have
per-request chunkqueues separate from per-connection chunkqueues.
Should probably also have a request_reset() which is distinct from
connection_reset().
convert all log_error_write() to log_error() and pass (log_error_st *)
use con->errh in preference to srv->errh (even though currently same)
avoid passing (server *) when previously used only for logging (errh)
