Update async to use epoll instead of poll

Makefile

@@ -35,7 +35,8 @@ bin/worker:
 bin/res:
 	mkdir -p bin/res
 
-bin/test: test/mock_*.c test/test_*.c src/lib/utils.c src/lib/sock.c src/lib/list.c
+bin/test: test/mock_*.c test/test_*.c \
+          src/lib/utils.c src/lib/sock.c src/lib/list.c src/lib/http.c src/lib/http_static.c src/logger.c
 	$(CC) -o $@ $(CFLAGS) $^ -lcriterion
 
 

src/async.c

@@ -11,32 +11,72 @@
 #include "lib/list.h"
 
 #include <poll.h>
+#include <sys/epoll.h>
 #include <signal.h>
 #include <errno.h>
 #include <memory.h>
 #include <pthread.h>
 #include <semaphore.h>
+#include <unistd.h>
+
+#define ASYNC_MAX_EVENTS 16
 
 typedef struct {
     int fd;
     sock *socket;
-    short events;
+    async_evt_t events;
     int flags;
-    void (*cb)(void *);
     void *arg;
+    void (*cb)(void *);
     void (*err_cb)(void *);
-    void *err_arg;
 } evt_listen_t;
 
 typedef struct {
     int n;
-    evt_listen_t q[64];
+    evt_listen_t *q[ASYNC_MAX_EVENTS];
 } listen_queue_t;
 
 static listen_queue_t listen1, listen2, *listen_q = &listen1;
 static volatile sig_atomic_t alive = 1;
 static pthread_t thread = -1;
 static sem_t lock;
+static int epoll_fd;
+
+static short async_a2p(async_evt_t events) {
+    short ret = 0;
+    if (events & ASYNC_IN)  ret |= POLLIN;
+    if (events & ASYNC_PRI) ret |= POLLPRI;
+    if (events & ASYNC_OUT) ret |= POLLOUT;
+    return ret;
+}
+
+static unsigned int async_a2e(async_evt_t events) {
+    unsigned int ret = 0;
+    if (events & ASYNC_IN)  ret |= EPOLLIN;
+    if (events & ASYNC_PRI) ret |= EPOLLPRI;
+    if (events & ASYNC_OUT) ret |= EPOLLOUT;
+    return ret;
+}
+
+static async_evt_t async_p2a(short events) {
+    async_evt_t ret = 0;
+    if (events & POLLIN)   ret |= ASYNC_IN;
+    if (events & POLLPRI)  ret |= ASYNC_PRI;
+    if (events & POLLOUT)  ret |= ASYNC_OUT;
+    if (events & POLLERR)  ret |= ASYNC_ERR;
+    if (events & POLLHUP)  ret |= ASYNC_HUP;
+    return ret;
+}
+
+static async_evt_t async_e2a(unsigned int events) {
+    async_evt_t ret = 0;
+    if (events & EPOLLIN)   ret |= ASYNC_IN;
+    if (events & EPOLLPRI)  ret |= ASYNC_PRI;
+    if (events & EPOLLOUT)  ret |= ASYNC_OUT;
+    if (events & EPOLLERR)  ret |= ASYNC_ERR;
+    if (events & EPOLLHUP)  ret |= ASYNC_HUP;
+    return ret;
+}
 
 static int async_add_to_queue(evt_listen_t *evt) {
     try_again:
@@ -48,19 +88,26 @@ static int async_add_to_queue(evt_listen_t *evt) {
         }
     }
 
-    memcpy(&listen_q->q[listen_q->n++], evt, sizeof(*evt));
+    evt_listen_t *ptr = malloc(sizeof(evt_listen_t));
+    if (ptr == NULL) {
+        sem_post(&lock);
+        return -1;
+    }
+
+    memcpy(ptr, evt, sizeof(*evt));
+    listen_q->q[listen_q->n++] = ptr;
 
     sem_post(&lock);
 
     return 0;
 }
 
-static int async_exec(evt_listen_t *evt, short r_events) {
+static int async_exec(evt_listen_t *evt, async_evt_t r_events) {
     int ret, e = errno;
     if (r_events & evt->events) {
         // specified event(s) occurred
         if (evt->socket && !sock_has_pending(evt->socket)) {
-            evt->err_cb(evt->err_arg);
+            evt->err_cb(evt->arg);
             ret = 0;
         } else {
             evt->cb(evt->arg);
@@ -68,7 +115,7 @@ static int async_exec(evt_listen_t *evt, short r_events) {
         }
     } else if (r_events & (POLLERR | POLLHUP | POLLNVAL)) {
         // error occurred
-        evt->err_cb(evt->err_arg);
+        evt->err_cb(evt->arg);
         ret = 0;
     } else {
         // no event occurred
@@ -81,12 +128,15 @@ static int async_exec(evt_listen_t *evt, short r_events) {
 }
 
 static int async_check(evt_listen_t *evt) {
-    struct pollfd fds[1] = {{.fd = evt->fd, .events = evt->events}};
+    struct pollfd fds[1] = {{
+        .fd = evt->fd,
+        .events = async_a2p(evt->events)
+    }};
 
     // check, if fd is already ready
     if (poll(fds, 1, 0) == 1) {
-        // fd already read
+        // fd already ready
-        if (async_exec(evt, fds[0].revents) == 0)
+        if (async_exec(evt, async_p2a(fds[0].revents)) == 0)
             return 1;
     }
 
@@ -104,30 +154,28 @@ static int async_add(evt_listen_t *evt) {
     return ret;
 }
 
-int async_fd(int fd, short events, int flags, void cb(void *), void *arg, void err_cb(void *), void *err_arg) {
+int async_fd(int fd, async_evt_t events, int flags, void *arg, void cb(void *), void err_cb(void *)) {
     evt_listen_t evt = {
             .fd = fd,
             .socket = NULL,
             .events = events,
             .flags = flags,
-            .cb = cb,
             .arg = arg,
+            .cb = cb,
             .err_cb = err_cb,
-            .err_arg = err_arg,
     };
     return async_add(&evt);
 }
 
-int async(sock *s, short events, int flags, void cb(void *), void *arg, void err_cb(void *), void *err_arg) {
+int async(sock *s, async_evt_t events, int flags, void *arg, void cb(void *), void err_cb(void *)) {
     evt_listen_t evt = {
             .fd = s->socket,
             .socket = s,
             .events = events,
             .flags = flags,
-            .cb = cb,
             .arg = arg,
+            .cb = cb,
             .err_cb = err_cb,
-            .err_arg = err_arg,
     };
     return async_add(&evt);
 }
@@ -140,19 +188,29 @@ int async_init(void) {
     listen1.n = 0;
     listen2.n = 0;
 
+    if ((epoll_fd = epoll_create1(0)) == -1) {
+        async_free();
+        return -1;
+    }
+
     return 0;
 }
 
 void async_free(void) {
     int e = errno;
     sem_destroy(&lock);
+    close(epoll_fd);
     errno = e;
 }
 
 void async_thread(void) {
-    evt_listen_t *local = list_create(sizeof(evt_listen_t), 16);
+    struct epoll_event ev, events[ASYNC_MAX_EVENTS];
-
+    int num_fds;
-    // TODO use epoll instead of poll
+    evt_listen_t **local = list_create(sizeof(evt_listen_t *), 16);
+    if (local == NULL) {
+        critical("Unable to create async local list");
+        return;
+    }
 
     thread = pthread_self();
 
@@ -162,23 +220,27 @@ void async_thread(void) {
         listen_queue_t *l = listen_q;
         listen_q = (listen_q == &listen1) ? &listen2 : &listen1;
 
-        // fill local list with previously added queue entries
+        // fill local list and epoll instance with previously added queue entries
         for (int i = 0; i < l->n; i++) {
-            local = list_append(local, &l->q[i]);
+            evt_listen_t *evt = l->q[i];
-        }
+            local = list_append(local, &evt);
+            if (local == NULL) {
+                critical("Unable to resize async local list");
+                return;
+            }
 
+            ev.events = async_a2e(evt->events);
+            ev.data.ptr = evt;
+
+            if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, evt->fd, &ev) == -1) {
+                critical("Unable to add file descriptor to epoll instance");
+                return;
+            }
+        }
         // reset size of queue
         l->n = 0;
 
-        // fill fds with newly added queue entries
+        if ((num_fds = epoll_wait(epoll_fd, events, ASYNC_MAX_EVENTS, -1)) == -1) {
-        int num_fds = 0;
-        struct pollfd fds[list_size(local)];
-        for (int i = 0; i < list_size(local); i++, num_fds++) {
-            fds[num_fds].fd = local[i].fd;
-            fds[num_fds].events = local[i].events;
-        }
-
-        if (poll(fds, num_fds, -1) < 0) {
             if (errno == EINTR) {
                 // interrupt
                 errno = 0;
@@ -190,13 +252,29 @@ void async_thread(void) {
             }
         }
 
-        for (int i = 0, j = 0; i < num_fds; i++, j++) {
+        for (int i = 0; i < num_fds; i++) {
-            evt_listen_t *evt = &local[j];
+            evt_listen_t *evt = events[i].data.ptr;
-            if (async_exec(evt, fds[i].revents) == 0)
+            if (async_exec(evt, async_e2a(events[i].events)) == 0) {
-                local = list_remove(local, j--);
+                if (epoll_ctl(epoll_fd, EPOLL_CTL_DEL, evt->fd, NULL) == -1) {
+                    critical("Unable to remove file descriptor from epoll instance");
+                    return;
+                }
+
+                local = list_delete(local, &evt);
+                if (local == NULL) {
+                    critical("Unable to resize async local list");
+                    return;
+                }
+
+                free(evt);
+            }
         }
     }
 
+    // cleanup
+    for (int i = 0; i < list_size(local); i++) {
+        free(local[i]);
+    }
     list_free(local);
 }
 

src/async.h

@@ -11,13 +11,22 @@
 
 #include "lib/sock.h"
 
-#include <poll.h>
-
 #define ASYNC_KEEP 1
 
-int async(sock *s, short events, int flags, void cb(void *), void *arg, void err_cb(void *), void *err_arg);
+#define ASYNC_IN   0x01
+#define ASYNC_PRI  0x02
+#define ASYNC_OUT  0x04
+#define ASYNC_ERR  0x08
+#define ASYNC_HUP  0x10
 
-int async_fd(int fd, short events, int flags, void cb(void *), void *arg, void err_cb(void *), void *err_arg);
+#define ASYNC_WAIT_READ  ASYNC_IN
+#define ASYNC_WAIT_WRITE ASYNC_OUT
+
+typedef unsigned int async_evt_t;
+
+int async(sock *s, async_evt_t events, int flags, void *arg, void cb(void *), void err_cb(void *));
+
+int async_fd(int fd, async_evt_t events, int flags, void *arg, void cb(void *), void err_cb(void *));
 
 int async_init(void);
 

src/server.c

@@ -296,7 +296,7 @@ int main(int argc, char *const argv[]) {
     workers_init();
 
     for (int i = 0; i < NUM_SOCKETS; i++) {
-        async_fd(sockets[i], POLLIN, ASYNC_KEEP, accept_cb, &sockets[i], accept_err_cb, &sockets[i]);
+        async_fd(sockets[i], ASYNC_WAIT_READ, ASYNC_KEEP, &sockets[i], accept_cb, accept_err_cb);
     }
 
     notice("Ready to accept connections");

src/workers.c

@@ -53,7 +53,7 @@ static int handle_request_cb(client_ctx_t *ctx) {
 
 int handle_request(client_ctx_t *ctx) {
     if (ctx->c_keep_alive && ctx->s_keep_alive) {
-        return async(&ctx->socket, POLLIN, 0, (void (*)(void *)) handle_request_cb, ctx, (void (*)(void *)) tcp_close, ctx);
+        return async(&ctx->socket, ASYNC_WAIT_READ, 0, ctx, (void (*)(void *)) handle_request_cb, (void (*)(void *)) tcp_close);
     } else {
         tcp_close(ctx);
         return 0;
@@ -77,5 +77,5 @@ static int ws_handle_frame_cb(ws_ctx_t *ctx) {
 }
 
 int ws_handle_frame(ws_ctx_t *ctx) {
-    return async(ctx->socket, POLLIN, 0, (void (*)(void *)) ws_handle_frame_cb, ctx, (void (*)(void *)) ws_close, ctx);
+    return async(ctx->socket, ASYNC_WAIT_READ, 0, ctx, (void (*)(void *)) ws_handle_frame_cb, (void (*)(void *)) ws_close);
 }