Add comments

Change-Id: If9ec624786a64cb716e37acbad0c8d30c3bb8265

diff --git a/src/utils-upoll.c b/src/utils-upoll.c
index 2a27025..b9b8de4 100644 (file)
--- a/src/utils-upoll.c
+++ b/src/utils-upoll.c
@@ -24,25 +24,48 @@
 
 #include "utils-upoll.h"
 
-
 struct upollfd;
 
+/*
+ * Structure describing one opened client
+ */
 struct upoll
 {
-       struct upollfd *fd;
-       void (*read)(void *);
-       void (*write)(void *);
-       void (*hangup)(void *);
-       void *closure;
-       struct upoll *next;
+       struct upollfd *fd;     /* structure handling the file descriptor */
+       void (*read)(void *);   /* callback for handling on_readable */
+       void (*write)(void *);  /* callback for handling on_writable */
+       void (*hangup)(void *); /* callback for handling on_hangup */
+       void *closure;          /* closure for callbacks */
+       struct upoll *next;     /* next client of the same file descriptor */
 };
 
+/*
+ * Structure describing a watched file descriptor
+ */
 struct upollfd
 {
-       int fd;
-       uint32_t events;
-       struct upollfd *next;
-       struct upoll *head;
+       int fd;                 /* watch file descriptor */
+       uint32_t events;        /* watched events */
+       struct upollfd *next;   /* next watched file descriptor */
+       struct upoll *head;     /* first client watching the file descriptor */
+};
+
+/*
+ * Structure describing a upoll group
+ */
+struct upollgrp
+{
+       int pollfd;
+       struct upollfd *head;
+       struct upoll *current;
+       pthread_mutex_t mutex;
+};
+
+static struct upollgrp global = {
+       .pollfd = 0,
+       .head = NULL,
+       .current = NULL,
+       .mutex = PTHREAD_MUTEX_INITIALIZER
 };
 
 static int pollfd = 0;
@@ -50,6 +73,9 @@ static struct upollfd *head = NULL;
 static struct upoll *current = NULL;
 static pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER;
 
+/*
+ *
+ */
 static int update(struct upollfd *ufd)
 {
        int rc;
@@ -95,6 +121,42 @@ static int update(struct upollfd *ufd)
        return rc;
 }
 
+/*
+ * Compute the events for the set of clients
+ */
+static int update_flags(struct upollfd *ufd)
+{
+       int rc;
+       struct upoll *u;
+       struct epoll_event e;
+       uint32_t events;
+       struct upollfd **prv;
+
+       /* compute expected events */
+       events = 0;
+       pthread_mutex_lock(&mutex);
+       u = ufd->head;
+       assert (u != NULL);
+       while (u != NULL) {
+               if (u->read != NULL)
+                       events |= EPOLLIN;
+               if (u->write != NULL)
+                       events |= EPOLLOUT;
+               u = u->next;
+       }
+       if (ufd->events == events)
+               rc = 0;
+       else {
+               e.events = events;
+               e.data.ptr = ufd;
+               rc = epoll_ctl(pollfd, EPOLL_CTL_MOD, ufd->fd, &e);
+               if (rc == 0)
+                       ufd->events = events;
+       }
+       pthread_mutex_unlock(&mutex);
+       return rc;
+}
+
 static struct upollfd *get_fd(int fd)
 {
        struct epoll_event e;