添加rtthread相关代码

riscv/rtthread/components/lwp/syscall_generic.h

@@ -0,0 +1,78 @@
+/*
+ * Copyright (c) 2006-2022, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2022-11-10     RT-Thread    The first version
+ * 2023-03-13     WangXiaoyao  syscall metadata as structure
+ */
+#ifndef __SYSCALL_DATA_H__
+#define __SYSCALL_DATA_H__
+
+#include <rtthread.h>
+
+#include <errno.h>
+#include <stdlib.h>
+
+typedef long sysret_t;
+
+struct rt_syscall_def
+{
+    void *func;
+    char *name;
+};
+
+/**
+ * @brief signature for syscall, used to locate syscall metadata.
+ *
+ * We don't allocate an exclusive section in ELF like Linux do
+ * to avoid initializing necessary data by iterating that section,
+ * which increases system booting time. We signature a pointer
+ * just below each syscall entry in syscall table to make it
+ * easy to locate every syscall's metadata by using syscall id.
+ */
+#define SYSCALL_SIGN(func) {    \
+    (void *)(func),             \
+    &RT_STRINGIFY(func)[4],     \
+}
+
+#define SET_ERRNO(no) rt_set_errno(-(no))
+#define GET_ERRNO() ({int _errno = rt_get_errno(); _errno > 0 ? -_errno : _errno;})
+
+#define _SYS_WRAP(func) ({int _ret = func; _ret < 0 ? GET_ERRNO() : _ret;})
+
+rt_inline sysret_t lwp_errno_to_posix(rt_err_t error)
+{
+    sysret_t posix_rc;
+
+    switch (labs(error))
+    {
+        case RT_EOK:
+            posix_rc = 0;
+            break;
+        case RT_ETIMEOUT:
+            posix_rc = -ETIMEDOUT;
+            break;
+        case RT_EINVAL:
+            posix_rc = -EINVAL;
+            break;
+        case RT_ENOENT:
+            posix_rc = -ENOENT;
+            break;
+        case RT_ENOSPC:
+            posix_rc = -ENOSPC;
+            break;
+        case RT_EPERM:
+            posix_rc = -EPERM;
+            break;
+        default:
+            posix_rc = -1;
+            break;
+    }
+
+    return posix_rc;
+}
+
+#endif /* __SYSCALL_DATA_H__ */