Previously if ngx_add_event() failed a connection was freed two times (once in the ngx_event_connect_peer(), and again by a caller) as pc->connection was left set. Fix is to always use ngx_close_connection() to close connection properly and set pc->connection to NULL on errors. Patch by Piotr Sikora.
It's already called by OPENSSL_config(). Calling it again causes some openssl engines (notably GOST) to corrupt memory, as they don't expect to be created more than once.
Support for TLSv1.1 and TLSv1.2 protocols was introduced in OpenSSL 1.0.1 (-beta1 was recently released). This change makes it possible to disable these protocols and/or enable them without other protocols.
Events from eventfd do not have c->write set, and the stale event check added in r4306 causes null pointer dereference.
It is currently used from master process on abnormal worker termination to unlock accept mutex (unlocking of accept mutex was broken in 1.0.2). It is expected to be used in the future to unlock other mutexes as well. Shared mutex code was rewritten to make this possible in a safe way, i.e. with a check if lock was actually held by the exited process. We again use pid to lock mutex, and use separate atomic variable for a count of processes waiting in sem_wait().
Stale write event may happen if epoll_wait() reported both read and write events, and processing of the read event closed descriptor. Patch by Yichun Zhang (agentzh).
If possible we now just extend already present file buffer in p->out chain instead of keeping ngx_buf_t for each buffer we've flushed to disk. This saves about 120 bytes of memory per buffer flushed to disk, and resolves high CPU usage observed in edge cases (due to coalescing these buffers on send).
1. In ngx_event_pipe_write_chain_to_temp_file() make sure to fully write all shadow buffers up to last_shadow. With this change recycled buffers cannot appear in p->out anymore. This also fixes segmentation faults observed due to ngx_event_pipe_write_chain_to_temp() not freeing any raw buffers while still returning NGX_OK. 2. In ngx_event_pipe_write_to_downstream() we now properly check for busy size as a size of buffers, not a size of data in these buffers. This fixes situations where all available buffers became busy (including segmentation faults due to this). 3. The ngx_event_pipe_free_shadow_raw_buf() function is dropped. It's incorrect and not needed.