move bufferevent initialization early in handle_handshake the error path needs an initialized bufferevent too, otherwise it'll crash when trying to write the response. This moves the initialisation early, right after the tls_handshake. Another option would be to initialise it in do_accept, but that may be too early.

don't die on ECONNABORTED ECONNABORTED is returned if a connections gets aborted after being queued before the accept(2). I had some cases of accept: Software caused connection abort on FreeBSD, this should avoid that.

don't work around a missing -Wno-unused-parameter It's been there for a long time, and it's frankly annoying to pretend to use parameters. Most of the time, they're there to satisfy an interface and nothings more.

Store clients inside a splay tree From day one we've been using a static array of client struct to hold the clients data. This has variuos drawbacks, among which: * reuse of the storage ("shades of heartbleed") * maximum fixed amount of clients connected at the same time * bugs are harder to debug The last point in particular is important because if we mess the client ids, or try to execute some functions (e.g. the various fcgi_*) after a client has been disconnected, it's harder to "see" this "use after free"-tier kind of bug. Now I'm using a splay tree to hold the data about the live connections. Each client' data is managed by malloc. If we try to access a client data after the disconnection we'll probably crash with a SIGSEGV and find the bug is more easy. Performance-wise the connection phase should be faster since we don't have to loop anymore to find an empty spot in the clients array, but some operations could be slightly slower (compare the O(1) access in an array with a SPLAY_FIND operation -- still be faster than O(n) thought.)

one FastCGI connection per client FastCGI is designed to multiplex requests over a single connection, so ideally the server can open only one connection per worker to the FastCGI application and that's that. Doing this kind of multiplexing makes the code harder to follow and easier to break/leak etc on the gmid side however. OpenBSD' httpd seems to open one connection per client, so why can't we too? One connection per request is still way better (lighter) than using CGI, and we can avoid all the pitfalls of the multiplexing (keeping track of "live ids", properly shut down etc...)

plug a memory leak c->req is set in client_read but never deallocated

fmt

libevent2 fix: unfreeze the client evbuffer libevent2 has this concept of "freezeness" of a buffer. It's a way to avoid accidentally write/remove data from the wrong "edge" of the buffer. The client_tls_{read,write} functions need to add/drain data from the opposite edge, hence the need for the unfreeze call. This is the minimum change in order to work on libevent2 too. Another way would be to define evbuffer_{un,}freeze as NOP on libevent 1, but it's ugly IMHO.

new I/O handling on top of bufferevents This is a big change in how gmid handles I/O. Initially we used a hand-written loop over poll(2), that then was evolved into something powered by libevent basic API. This meant that there were a lot of small "asynchronous" function that did one step, eventually scheduling the re-execution, that called each others in a chain. The new implementation revolves completely around libevent' bufferevents. It's more clear, as everything is implemented around the client_read and client_write functions. There is still space for improvements, like adding timeouts for one, but it's solid enough to be committed as is and then further improved.

fastcgi completely asynchronous This changes the fastcgi implementation from a blocking I/O to an async implementation on top of libevent' bufferevents. Should improve the responsiveness of gmid especially when using remote fastcgi applications.

initialize mbufhead

fix possible out-of-bound access While computing the parent directory it an out-of-bound access can occur, which usually means the server process dies. In particular, it can be triggered by making a request for a non-existent file in the root of a virtual host if the path matches the `cgi` pattern. Thanks cage for helping in debugging!

style

drop unnecessary bzero the whole struct client is already memset'd to 0 in do_accept. handle_handshake doesn't touch the request or iri buffer in the code path that leads to handle_open_conn. (It does so in the error router alone.)

making more explicit the case of missing SNI Missing SNI (i.e. servname == NULL) is already handled correctly. puny_decode refuses to work on NULL servname, c->domain is still the empty string and everything flows as expected towards the error at the end. However, it's better to bail out early and make more explicit how the case of missing SNI is handled.