import RT-Thread@9217865c without bsp, libcpu and components/net

components/libc/compilers/dlib/syscall_read.c

@@ -0,0 +1,65 @@
+/*
+ * Copyright (c) 2006-2021, RT-Thread Development Team
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ *
+ * Change Logs:
+ * Date           Author       Notes
+ * 2015-01-28     Bernard      first version
+ */
+
+#include <rtthread.h>
+#include <LowLevelIOInterface.h>
+#include <unistd.h>
+#ifdef RT_USING_POSIX_STDIO
+#include "libc.h"
+#endif /* RT_USING_POSIX_STDIO */
+#include <compiler_private.h>
+#define DBG_TAG    "dlib.syscall.read"
+#define DBG_LVL    DBG_INFO
+#include <rtdbg.h>
+
+/*
+ * The "__read" function reads a number of bytes, at most "size" into
+ * the memory area pointed to by "buffer".  It returns the number of
+ * bytes read, 0 at the end of the file, or _LLIO_ERROR if failure
+ * occurs.
+ *
+ * The template implementation below assumes that the application
+ * provides the function "MyLowLevelGetchar".  It should return a
+ * character value, or -1 on failure.
+ */
+
+#pragma module_name = "?__read"
+
+size_t __read(int handle, unsigned char *buf, size_t len)
+{
+#ifdef DFS_USING_POSIX
+    int size;
+
+    if (handle == _LLIO_STDIN)
+    {
+#ifdef RT_USING_POSIX_STDIO
+        if (libc_stdio_get_console() < 0)
+        {
+            LOG_W("Do not invoke standard input before initializing Compiler");
+            return 0; /* error, but keep going */
+        }
+        return read(STDIN_FILENO, buf, len); /* return the length of the data read */
+#else
+        LOG_W(_WARNING_WITHOUT_STDIO);
+        return _LLIO_ERROR;
+#endif /* RT_USING_POSIX_STDIO */
+    }
+    else if ((handle == _LLIO_STDOUT) || (handle == _LLIO_STDERR))
+    {
+        return _LLIO_ERROR;
+    }
+
+    size = read(handle, buf, len);
+    return size; /* return the length of the data read */
+#else
+    LOG_W(_WARNING_WITHOUT_FS);
+    return _LLIO_ERROR;
+#endif /* DFS_USING_POSIX */
+}