Mercurial > hg > nginx-quic
diff src/event/modules/ngx_select_module.c @ 0:4eff17414a43
nginx-0.0.1-2002-08-06-20:39:45 import
The first code that uses "ngx_" prefix, the previous one used "gx_" prefix.
At that point the code is not yet usable. The first draft ideas are dated
back to 23.10.2001.
author | Igor Sysoev <igor@sysoev.ru> |
---|---|
date | Tue, 06 Aug 2002 16:39:45 +0000 |
parents | |
children | 669801705ab1 |
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new file mode 100644 --- /dev/null +++ b/src/event/modules/ngx_select_module.c @@ -0,0 +1,349 @@ + +#include <ngx_config.h> +#include <ngx_types.h> +#include <ngx_log.h> +#include <ngx_time.h> +#include <ngx_connection.h> +#include <ngx_event.h> +#include <ngx_select_module.h> + +static fd_set master_read_fds; +static fd_set master_write_fds; +static fd_set work_read_fds; +static fd_set work_write_fds; + +#if (WIN32) +static int max_read; +static int max_write; +#else +static int max_fd; +#endif + +static ngx_event_t event_queue; +static ngx_event_t timer_queue; + + +static void ngx_add_timer(ngx_event_t *ev, u_int timer); +static void ngx_inline ngx_del_timer(ngx_event_t *ev); + +static fd_set *ngx_select_get_fd_set(ngx_socket_t fd, int event, + ngx_log_t *log); + +void ngx_select_init(int max_connections, ngx_log_t *log) +{ +#if (WIN32) + if (max_connections > FD_SETSIZE) + ngx_log_error(NGX_LOG_EMERG, log, 0, + "ngx_select_init: maximum number of descriptors " + "supported by select() is %d", + FD_SETSIZE); +#else + if (max_connections >= FD_SETSIZE) + ngx_log_error(NGX_LOG_EMERG, log, 0, + "ngx_select_init: maximum descriptor number" + "supported by select() is %d", + FD_SETSIZE - 1); +#endif + + FD_ZERO(&master_read_fds); + FD_ZERO(&master_write_fds); + + event_queue.prev = &event_queue; + event_queue.next = &event_queue; + + timer_queue.timer_prev = &timer_queue; + timer_queue.timer_next = &timer_queue; + + ngx_event_actions.add = ngx_select_add_event; + ngx_event_actions.del = ngx_select_del_event; + ngx_event_actions.process = ngx_select_process_events; + +#if (WIN32) + max_read = max_write = 0; +#else + max_fd = -1; +#endif +} + +int ngx_select_add_event(ngx_event_t *ev, int event, u_int flags) +{ + fd_set *fds; + ngx_connection_t *cn = (ngx_connection_t *) ev->data; + + if (event == NGX_TIMER_EVENT) { + ngx_add_timer(ev, flags); + return 0; + } + + ngx_assert((flags != NGX_ONESHOT_EVENT), return -1, ev->log, + "ngx_select_add_event: NGX_ONESHOT_EVENT is not supported"); + + fds = ngx_select_get_fd_set(cn->fd, event, ev->log); + if (fds == NULL) + return -1; + + ev->prev = &event_queue; + ev->next = event_queue.next; + event_queue.next->prev = ev; + event_queue.next = ev; + + FD_SET(cn->fd, fds); + +#if (WIN32) + switch (event) { + case NGX_READ_EVENT: + max_read++; + break; + case NGX_WRITE_EVENT: + max_write++; + break; + } +#else + if (max_fd != -1 && max_fd < cn->fd) + max_fd = cn->fd; +#endif + + return 0; +} + +int ngx_select_del_event(ngx_event_t *ev, int event) +{ + fd_set *fds; + ngx_connection_t *cn = (ngx_connection_t *) ev->data; + + if (event == NGX_TIMER_EVENT) { + ngx_del_timer(ev); + return 0; + } + + fds = ngx_select_get_fd_set(cn->fd, event, ev->log); + if (fds == NULL) + return -1; + + if (ev->prev) + ev->prev->next = ev->next; + + if (ev->next) { + ev->next->prev = ev->prev; + ev->prev = NULL; + } + + if (ev->prev) + ev->next = NULL; + + FD_CLR(cn->fd, fds); + +#if (WIN32) + switch (event) { + case NGX_READ_EVENT: + max_read--; + break; + case NGX_WRITE_EVENT: + max_write--; + break; + } +#else + if (max_fd == cn->fd) + max_fd = -1; +#endif + + return 0; +} + +static fd_set *ngx_select_get_fd_set(ngx_socket_t fd, int event, ngx_log_t *log) +{ + ngx_log_debug(log, "ngx_select_get_fd_set: %d %d" _ fd _ event); + +#if !(WIN32) + if (fd >= FD_SETSIZE) { + ngx_log_error(NGX_LOG_ERR, log, 0, + "ngx_select_get_event: maximum descriptor number" + "supported by select() is %d", + FD_SETSIZE - 1); + return NULL; + } +#endif + + switch (event) { + case NGX_READ_EVENT: +#if (WIN32) + if (max_read >= FD_SETSIZE) { + ngx_log_error(NGX_LOG_ERR, log, 0, + "ngx_select_get_event: maximum number of descriptors " + "supported by select() is %d", + FD_SETSIZE); + return NULL; + } +#endif + return &master_read_fds; + + case NGX_WRITE_EVENT: +#if (WIN32) + if (max_write >= FD_SETSIZE) { + ngx_log_error(NGX_LOG_ERR, log, 0, + "ngx_select_get_event: maximum number of descriptors " + "supported by select() is %d", + FD_SETSIZE); + return NULL; + } +#endif + return &master_write_fds; + + default: + ngx_assert(0, return NULL, log, + "ngx_select_get_fd_set: invalid event %d" _ event); + } + + return NULL; +} + +int ngx_select_process_events(ngx_log_t *log) +{ + int ready, found; + u_int timer, delta; + ngx_event_t *ev, *nx; + ngx_connection_t *cn; + struct timeval tv, *tp; + + work_read_fds = master_read_fds; + work_write_fds = master_write_fds; + + if (timer_queue.timer_next != &timer_queue) { + timer = timer_queue.timer_next->timer_delta; + tv.tv_sec = timer / 1000; + tv.tv_usec = (timer % 1000) * 1000; + tp = &tv; + + delta = ngx_msec(); + + } else { + timer = 0; + tp = NULL; + delta = 0; + } + +#if !(WIN32) + if (max_fd == -1) { + for (ev = event_queue.next; ev != &event_queue; ev = ev->next) { + cn = (ngx_connection_t *) ev->data; + if (max_fd < cn->fd) + max_fd = cn->fd; + } + + ngx_log_debug(log, "ngx_select_process_events: change max_fd: %d" _ + max_fd); + } +#endif + + ngx_log_debug(log, "ngx_select_process_events: timer: %d" _ timer); + +#if (WIN32) + if ((ready = select(0, &work_read_fds, &work_write_fds, NULL, tp)) +#else + if ((ready = select(max_fd + 1, &work_read_fds, &work_write_fds, NULL, tp)) +#endif + == -1) { + ngx_log_error(NGX_LOG_ALERT, log, ngx_socket_errno, + "ngx_select_process_events: select failed"); + return -1; + } + + ngx_log_debug(log, "ngx_select_process_events: ready %d" _ ready); + + if (timer) { + delta = ngx_msec() - delta; + + } else { + ngx_assert((ready != 0), return -1, log, + "ngx_select_process_events: " + "select returns no events without timeout"); + } + + ngx_log_debug(log, "ngx_select_process_events: " + "timer: %d, delta: %d" _ timer _ delta); + + if (timer) { + if (delta >= timer) { + for (ev = timer_queue.timer_next; + ev != &timer_queue && delta >= ev->timer_delta; + /* void */) + { + delta -= ev->timer_delta; + nx = ev->timer_next; + ngx_del_timer(ev); + if (ev->timer_handler(ev) == -1) + ev->close_handler(ev); + ev = nx; + } + + } else { + timer_queue.timer_next->timer_delta -= delta; + } + } + + for (ev = event_queue.next; ev != &event_queue; ev = ev->next) { + cn = (ngx_connection_t *) ev->data; + found = 0; + + if (ev->write) { + if (FD_ISSET(cn->fd, &work_write_fds)) { + ngx_log_debug(log, "ngx_select_process_events: write %d" _ + cn->fd); + found = 1; + } + + } else { + if (FD_ISSET(cn->fd, &work_read_fds)) { + ngx_log_debug(log, "ngx_select_process_events: read %d" _ + cn->fd); + found = 1; + } + } + + if (found) { + ev->ready = 1; + if (ev->event_handler(ev) == -1) + ev->close_handler(ev); + + ready--; + } + + } + + ngx_assert((ready == 0), return 0, log, + "ngx_select_process_events: ready != events"); + + return 0; +} + +static void ngx_add_timer(ngx_event_t *ev, u_int timer) +{ + ngx_event_t *e; + + for (e = timer_queue.timer_next; + e != &timer_queue && timer > e->timer_delta; + e = e->timer_next) + timer -= e->timer_delta; + + ev->timer_delta = timer; + + ev->timer_next = e; + ev->timer_prev = e->timer_prev; + + e->timer_prev->timer_next = ev; + e->timer_prev = ev; +} + +static void ngx_inline ngx_del_timer(ngx_event_t *ev) +{ + if (ev->timer_prev) + ev->timer_prev->timer_next = ev->timer_next; + + if (ev->timer_next) { + ev->timer_next->timer_prev = ev->timer_prev; + ev->timer_prev = NULL; + } + + if (ev->timer_prev) + ev->timer_next = NULL; +}