ae_select module added

ae_select.c

+/* Select()-based ae.c module
+ * Copyright (C) 2009 Salvatore Sanfilippo - antirez@gmail.com
+ * Released under the BSD license. See the COPYING file for more info. */
+
+#include <string.h>
+
+typedef struct aeApiState {
+    fd_set rfds, wfds, efds;
+    /* We need to have a copy of the fd sets as it's not safe to reuse
+     * FD sets after select(). */
+    fd_set _rfds, _wfds, _efds;
+} aeApiState;
+
+static int aeApiCreate(aeEventLoop *eventLoop) {
+    aeApiState *state = zmalloc(sizeof(aeApiState));
+
+    if (!state) return -1;
+    FD_ZERO(&state->rfds);
+    FD_ZERO(&state->wfds);
+    FD_ZERO(&state->efds);
+    eventLoop->apidata = state;
+    return 0;
+}
+
+static void aeApiFree(aeEventLoop *eventLoop) {
+    zfree(eventLoop->apidata);
+}
+
+static int aeApiAddEvent(aeEventLoop *eventLoop, int fd, int mask) {
+    aeApiState *state = eventLoop->apidata;
+
+    if (mask & AE_READABLE) FD_SET(fd,&state->rfds);
+    if (mask & AE_WRITABLE) FD_SET(fd,&state->wfds);
+    if (mask & AE_EXCEPTION) FD_SET(fd,&state->efds);
+    return 0;
+}
+
+static void aeApiDelEvent(aeEventLoop *eventLoop, int fd, int mask) {
+    aeApiState *state = eventLoop->apidata;
+
+    if (mask & AE_READABLE) FD_CLR(fd,&state->rfds);
+    if (mask & AE_WRITABLE) FD_CLR(fd,&state->wfds);
+    if (mask & AE_EXCEPTION) FD_CLR(fd,&state->efds);
+}
+
+static int aeApiPoll(aeEventLoop *eventLoop, struct timeval *tvp) {
+    aeApiState *state = eventLoop->apidata;
+    int retval, j, numevents = 0;
+
+    memcpy(&state->_rfds,&state->rfds,sizeof(fd_set));
+    memcpy(&state->_wfds,&state->wfds,sizeof(fd_set));
+    memcpy(&state->_efds,&state->efds,sizeof(fd_set));
+
+    retval = select(eventLoop->maxfd+1,
+                &state->_rfds,&state->_wfds,&state->_efds,tvp);
+    if (retval > 0) {
+        for (j = 0; j <= eventLoop->maxfd; j++) {
+            int mask = 0;
+            aeFileEvent *fe = &eventLoop->events[j];
+
+            if (fe->mask == AE_NONE) continue;
+            if (fe->mask & AE_READABLE && FD_ISSET(j,&state->_rfds))
+                mask |= AE_READABLE;
+            if (fe->mask & AE_WRITABLE && FD_ISSET(j,&state->_wfds))
+                mask |= AE_WRITABLE;
+            if (fe->mask & AE_EXCEPTION && FD_ISSET(j,&state->_efds))
+                mask |= AE_EXCEPTION;
+            eventLoop->fired[numevents].fd = j;
+            eventLoop->fired[numevents].mask = mask;
+            numevents++;
+        }
+    }
+    return numevents;
+}