The Association of Connection and read and write events in Nginx event processing

/********************************************************************* * Author:samson * date:07/08/2015 * Test PL Atform: * GCC (Ubuntu 4.8.2-19ubuntu1) 4.8.2 * GNU bash, 4.3.11 (1)-release (X86_64-PC-LINUX-GNU)  * Nginx Version: *              Nginx 1.6.2 *              nginx 1.8.0 * *******************************************************************/

Connection and read, write events associated with Nginx event handling:

Rev = c->read;ngx_handle_read_event (rev, 0) is often seen in Nginx code, so what is rev?

What is the ev->data in ngx_connection_t *c = ev->data; in ngx_epoll_add_event?

In fact, all this is found in the ngx_event_process_init, in this function, the cycle of the global structure of the read_events, write_events, connections the generation of space and the correlation between the three.

The generated code for these 3 structures:

Cycle->connections = Ngx_alloc (sizeof (ngx_connection_t) * cycle->connection_n, Cycle->log);

cycle->read_events = Ngx_alloc (sizeof (ngx_event_t) * cycle->connection_n, Cycle->log);

cycle->write_events = Ngx_alloc (sizeof (ngx_event_t) * cycle->connection_n, Cycle->log);

Read_events, write_events, connections, the three in the cycle of the subscript equal to the expression is a connected event and connection of the corresponding FD information, which will be directly used in the later time

c = cycle->connections;

i = cycle->connection_n;

Next = NULL;

do {

i--;

C[i].data = Next;

C[i].read = &cycle->read_events[i];

C[i].write = &cycle->write_events[i];

C[I].FD = (ngx_socket_t)-1;

Next = &c[i];

#if (Ngx_threads)

C[i].lock = 0;

#endif

} while (i);

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The Association of Connection and read and write events in Nginx event processing