From 21c7d7a9d2ab9b1bd8ed8a1c78aade6e73b9a9d6 Mon Sep 17 00:00:00 2001
From: Xu Si Yu <xusiyu@espressif.com>
Date: Fri, 8 Mar 2024 12:27:10 +0800
Subject: [PATCH] fix(vfs): fix eventfd select

---
 .../vfs/test_apps/main/test_vfs_eventfd.c     | 47 ++++++++++++++++++-
 components/vfs/vfs_eventfd.c                  |  2 +-
 2 files changed, 47 insertions(+), 2 deletions(-)

diff --git a/components/vfs/test_apps/main/test_vfs_eventfd.c b/components/vfs/test_apps/main/test_vfs_eventfd.c
index 906bdecd1c..11ea46997d 100644
--- a/components/vfs/test_apps/main/test_vfs_eventfd.c
+++ b/components/vfs/test_apps/main/test_vfs_eventfd.c
@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2021-2022 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2021-2024 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Apache-2.0
  */
@@ -349,3 +349,48 @@ TEST_CASE("eventfd multiple selects", "[vfs][eventfd]")
     TEST_ASSERT_EQUAL(0, close(fd));
     TEST_ESP_OK(esp_vfs_eventfd_unregister());
 }
+
+typedef struct {
+    int *value;
+    int fd;
+} select_block_task_args_t;
+
+static void select_block_task(void *arg)
+{
+    int fd = ((select_block_task_args_t *)arg)->fd;
+    fd_set read_fds;
+
+    FD_ZERO(&read_fds);
+    FD_SET(fd, &read_fds);
+
+    select(fd + 1, &read_fds, NULL, NULL, NULL);
+    *(((select_block_task_args_t *)arg)->value) = 1;
+    vTaskDelete(NULL);
+}
+
+TEST_CASE("eventfd select block", "[vfs][eventfd]")
+{
+    esp_vfs_eventfd_config_t config = ESP_VFS_EVENTD_CONFIG_DEFAULT();
+    TEST_ESP_OK(esp_vfs_eventfd_register(&config));
+
+    select_block_task_args_t args;
+    args.fd = eventfd(0, 0);
+    TEST_ASSERT_GREATER_OR_EQUAL(0, args.fd);
+    int a = 0;
+    args.value = &a;
+
+    int fd_write = eventfd(0, 0);
+    TEST_ASSERT_GREATER_OR_EQUAL(0, fd_write);
+
+    xTaskCreate(select_block_task, "select_block_task", 2048, &args, 5, NULL);
+    vTaskDelay(pdMS_TO_TICKS(2000));
+
+    uint64_t val = 1;
+    TEST_ASSERT_EQUAL(sizeof(val), write(fd_write, &val, sizeof(val)));
+    vTaskDelay(pdMS_TO_TICKS(2000));
+
+    TEST_ASSERT_EQUAL(0, *(args.value));
+    TEST_ASSERT_EQUAL(0, close(args.fd));
+    TEST_ASSERT_EQUAL(0, close(fd_write));
+    TEST_ESP_OK(esp_vfs_eventfd_unregister());
+}
diff --git a/components/vfs/vfs_eventfd.c b/components/vfs/vfs_eventfd.c
index 11ff2fb7e7..a9a979cf9c 100644
--- a/components/vfs/vfs_eventfd.c
+++ b/components/vfs/vfs_eventfd.c
@@ -106,7 +106,7 @@ static esp_err_t event_start_select(int                  nfds,
 
     for (int i = 0; i < nfds; i++) {
         _lock_acquire_recursive(&s_events[i].lock);
-        if (s_events[i].fd == i) {
+        if (s_events[i].fd == i && (FD_ISSET(i, readfds) || FD_ISSET(i, writefds) || FD_ISSET(i, exceptfds))) {
             if (s_events[i].support_isr) {
                 portENTER_CRITICAL(&s_events[i].data_spin_lock);
             }