Add simple epoll' wrapper around poll'

Signed-off-by: Anton D. Kachalov <mouse@yandex-team.ru>

fs/vfs/Make.defs

@@ -68,7 +68,7 @@ else
 CSRCS += fs_close.c fs_dup.c fs_dup2.c fs_fcntl.c fs_dupfd.c fs_dupfd2.c
 CSRCS += fs_getfilep.c fs_ioctl.c fs_lseek.c fs_mkdir.c fs_open.c fs_poll.c 
 CSRCS += fs_read.c fs_rename.c fs_rmdir.c fs_stat.c fs_statfs.c fs_select.c
-CSRCS += fs_unlink.c fs_write.c
+CSRCS += fs_unlink.c fs_write.c epoll.c
 
 # Certain interfaces are not available if there is no mountpoint support
 

fs/vfs/epoll.c

@@ -0,0 +1,102 @@
+#include <stdint.h>
+#include <poll.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <sys/epoll.h>
+
+int epoll_create(int size)
+{
+  struct epoll_head *eph = malloc(sizeof(struct epoll_head));
+
+  eph->size = size;
+  eph->occupied = 0;
+  eph->evs = malloc(sizeof(struct epoll_event) * eph->size);
+
+  return (int)eph;
+}
+
+void epoll_close(int epfd)
+{
+  struct epoll_head *eph = (struct epoll_head *)epfd;
+
+  free(eph->evs);
+  free(eph);
+}
+
+int epoll_ctl(int epfd, int op, int fd, struct epoll_event *ev)
+{
+  struct epoll_head *eph = (struct epoll_head *)epfd;
+
+  switch (op)
+    {
+      case EPOLL_CTL_ADD:
+        printf("%08x CTL ADD(%d): fd=%d ev=%08x\n", epfd, eph->occupied, fd, ev->events);
+        eph->evs[eph->occupied].events = ev->events | POLLERR | POLLHUP;
+        eph->evs[eph->occupied++].data.fd = fd;
+        return 0;
+
+      case EPOLL_CTL_DEL:
+        {
+          int i;
+          for (i=0; i < eph->occupied; i++)
+            {
+              if (eph->evs[i].data.fd == fd)
+                {
+                  if (i != eph->occupied-1)
+                    memmove(&eph->evs[i], &eph->evs[i + 1], eph->occupied - i);
+                  eph->occupied--;
+                  return 0;
+                }
+            }
+          return -ENOENT;
+        }
+
+      case EPOLL_CTL_MOD:
+        {
+          int i;
+          printf("%08x CTL MOD(%d): fd=%d ev=%08x\n", epfd, eph->occupied, fd, ev->events);
+          for (i=0; i < eph->occupied; i++)
+            {
+              if (eph->evs[i].data.fd == fd)
+                {
+                  eph->evs[i].events = ev->events | POLLERR | POLLHUP;
+                  return 0;
+                }
+            }
+          return -ENOENT;
+        }
+    }
+
+  return -EINVAL;
+}
+
+int epoll_wait(int epfd, struct epoll_event *evs, int maxevents, int timeout)
+{
+  int i;
+  int rc;
+  struct epoll_head *eph = (struct epoll_head *)epfd;
+
+  rc = poll((struct pollfd *)eph->evs, eph->occupied, timeout);
+
+  if (rc <= 0)
+    {
+      if (rc < 0) {
+      printf("%08x poll fail: %d for %d, %d msecs\n", epfd, rc, eph->occupied, timeout);
+      for (i=0; i < eph->occupied; i++)
+        {
+          printf("%02d: fd=%d\n", i, eph->evs[i].data.fd);
+        }
+      }
+      return rc;
+    }
+
+  for (i=0; i < rc; i++)
+    {
+      evs[i].data.fd = (pollevent_t)eph->evs[i].data.fd;
+      evs[i].events = (pollevent_t)eph->evs[i].revents;
+    }
+
+  return rc;
+}

include/sys/epoll.h

@@ -0,0 +1,59 @@
+#ifndef _EPOLL__H
+#define _EPOLL__H
+
+#include <poll.h>
+
+enum EPOLL_EVENTS
+  {
+    EPOLLIN = POLLIN,
+#define EPOLLIN EPOLLIN
+    EPOLLPRI = POLLPRI,
+#define EPOLLPRI EPOLLPRI
+    EPOLLOUT = POLLOUT,
+#define EPOLLOUT EPOLLOUT
+    EPOLLRDNORM = POLLRDNORM,
+#define EPOLLRDNORM EPOLLRDNORM
+    EPOLLRDBAND = POLLRDBAND,
+#define EPOLLRDBAND EPOLLRDBAND
+    EPOLLWRNORM = POLLWRNORM,
+#define EPOLLWRNORM EPOLLWRNORM
+    EPOLLWRBAND = POLLWRBAND,
+#define EPOLLWRBAND EPOLLWRBAND
+    EPOLLERR = POLLERR,
+#define EPOLLERR EPOLLERR
+    EPOLLHUP = POLLHUP,
+#define EPOLLHUP EPOLLHUP
+  };
+
+#define EPOLL_CTL_ADD 1 /* Add a file descriptor to the interface.  */
+#define EPOLL_CTL_DEL 2 /* Remove a file descriptor from the interface.  */
+#define EPOLL_CTL_MOD 3 /* Change file descriptor epoll_event structure.  */
+
+typedef union poll_data
+{
+  int         fd;       /* The descriptor being polled */
+} epoll_data_t;
+
+struct epoll_event
+{
+  epoll_data_t data;
+  sem_t       *sem;      /* Pointer to semaphore used to post output event */
+  pollevent_t  events;   /* The input event flags */
+  pollevent_t  revents;  /* The output event flags */
+  FAR void    *priv;     /* For use by drivers */
+};
+
+struct epoll_head
+{
+  int size;
+  int occupied;
+  struct epoll_event *evs;
+};
+
+int epoll_create(int size);
+int epoll_ctl(int epfd, int op, int fd, struct epoll_event *ev);
+int epoll_wait(int epfd, struct epoll_event *evs, int maxevents, int timeout);
+
+void epoll_close(int epfd);
+
+#endif