Fix bug swoole#4327 mkdir create failed on coroutines (swoole#4337)

* fix bug swoole#4327

* fix bug swoole#4327

* fix bug swoole#4327

* unit test

* 代码格式

* 单元测试

* 修复无符号和有符号之间的比较

* unit test

* unit test

Author: NathanFreeman

tests/swoole_runtime/file_hook/bug_4327.phpt

@@ -0,0 +1,56 @@
+--TEST--
+mkdir failed when coroutines: bug #4372
+--SKIPIF--
+<?php
+require __DIR__ . '/../../include/skipif.inc';
+?>
+--FILE--
+<?php
+
+use Swoole\Coroutine;
+use Swoole\Coroutine\Barrier;
+use function Swoole\Coroutine\run;
+
+require __DIR__.'/../../include/bootstrap.php';
+
+Swoole\Runtime::enableCoroutine($flags = SWOOLE_HOOK_ALL);
+
+function createDirectories($protocol = "")
+{
+    $barrier = Barrier::make();
+    $first   = "$protocol/".rand(0, 1000);
+    $second  = "/".rand(0, 1000);
+    $third   = "/".rand(0, 1000)."/";
+
+    for ($i = 0; $i < 5; $i++) {
+        Coroutine::create(static function () use ($i, $first, $second, $third, $barrier) {
+            if (!mkdir($directory = $first.$second.$third.$i, 0755, true) && !is_dir($directory)) {
+                throw new Exception("create directory failed");
+            }
+            rmdir($directory);
+        });
+    }
+    echo "SUCCESS".PHP_EOL;
+
+    Barrier::wait($barrier);
+    rmdir($first.$second.$third);
+    rmdir($first.$second);
+    rmdir($first);
+}
+
+
+run(function () {
+    createDirectories();
+    createDirectories("file://");
+});
+
+Swoole\Runtime::enableCoroutine(false);
+createDirectories();
+createDirectories("file://");
+?>
+
+--EXPECT--
+SUCCESS
+SUCCESS
+SUCCESS
+SUCCESS

thirdparty/php/streams/plain_wrapper.c

@@ -1085,7 +1085,7 @@ static int php_plain_files_mkdir(
 
         if (p == buf) {
             ret = mkdir(dir, mode);
-        } else if (!(ret = mkdir(buf, mode))) {
+        } else if (!(ret = mkdir(buf, mode)) || EEXIST == errno) {
             if (!p) {
                 p = buf;
             }
@@ -1094,6 +1094,11 @@ static int php_plain_files_mkdir(
                 if (*p == '\0') {
                     *p = DEFAULT_SLASH;
                     if ((*(p + 1) != '\0') && (ret = mkdir(buf, (mode_t) mode)) < 0) {
+                        // parent directory already exists and try to create child directories.
+                        if (EEXIST == errno && (int) strlen(buf) < dir_len) {
+                            continue;
+                        }
+
                         if (options & REPORT_ERRORS) {
                             php_error_docref(NULL, E_WARNING, "%s", strerror(errno));
                         }