[MINOR] add support for the polling results in fdtab

Now fdtab can contain the FD_POLL_* events so that the pollers
which can fill them can give userful information to readers and
writers about the precise condition of wakeup.

include/types/fd.h

@@ -43,14 +43,26 @@ enum {
 	DIR_SIZE
 };
 
+
+#define FD_POLL_IN	0x01
+#define FD_POLL_PRI	0x02
+#define FD_POLL_OUT	0x04
+#define FD_POLL_ERR	0x08
+#define FD_POLL_HUP	0x10
+#define FD_POLL_ANY	0x1F
+
+#define FD_POLL_RD	(FD_POLL_IN  | FD_POLL_ERR | FD_POLL_HUP)
+#define FD_POLL_WR	(FD_POLL_OUT | FD_POLL_ERR | FD_POLL_HUP)
+
 /* info about one given fd */
 struct fdtab {
 	struct {
 		int (*f)(int fd);            /* read/write function */
 		struct buffer *b;            /* read/write buffer */
 	} cb[DIR_SIZE];
-	struct task *owner;             /* the session (or proxy) associated with this fd */
-	int state;                      /* the state of this fd */
+	struct task *owner;                  /* the session (or proxy) associated with this fd */
+	unsigned char state;                 /* the state of this fd */
+	unsigned char ev;                    /* event seen in return of poll() : FD_POLL_* */
 };
 
 /*

src/checks.c

@@ -336,6 +336,7 @@ int process_chk(struct task *t)
 						fdtab[fd].cb[DIR_WR].f = &event_srv_chk_w;
 						fdtab[fd].cb[DIR_WR].b = NULL;
 						fdtab[fd].state = FD_STCONN; /* connection in progress */
+						fdtab[fd].ev = 0;
 						EV_FD_SET(fd, DIR_WR);  /* for connect status */
 #ifdef DEBUG_FULL
 						assert (!EV_FD_ISSET(fd, DIR_RD));

src/client.c

@@ -385,6 +385,7 @@ int event_accept(int fd) {
 		fdtab[cfd].cb[DIR_RD].b = s->req;
 		fdtab[cfd].cb[DIR_WR].f = &stream_sock_write;
 		fdtab[cfd].cb[DIR_WR].b = s->rep;
+		fdtab[cfd].ev = 0;
 
 		if ((p->mode == PR_MODE_HTTP && (s->flags & SN_MONITOR)) ||
 		    (p->mode == PR_MODE_HEALTH && (p->options & PR_O_HTTP_CHK))) {

src/proxy.c

@@ -153,6 +153,7 @@ int start_proxies(int verbose)
 			fdtab[fd].cb[DIR_RD].b = fdtab[fd].cb[DIR_WR].b = NULL;
 			fdtab[fd].owner = (struct task *)curproxy; /* reference the proxy instead of a task */
 			fdtab[fd].state = FD_STLISTEN;
+			fdtab[fd].ev = 0;
 			listeners++;
 		}