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Diffstat (limited to 'src/event/modules/ngx_select_module.c')
-rw-r--r--src/event/modules/ngx_select_module.c349
1 files changed, 349 insertions, 0 deletions
diff --git a/src/event/modules/ngx_select_module.c b/src/event/modules/ngx_select_module.c
new file mode 100644
index 000000000..6c9e8f3c2
--- /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;
+}
generated by cgit v1.2.3 (git 2.25.1) at 2025-07-15 17:56:25 +0000