[libc] Change libc stubs to compiler folder.

components/libc/compilers/newlib/libc.c

@@ -0,0 +1,56 @@
+#include <rtthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <sys/time.h>
+#include "libc.h"
+
+#ifdef RT_USING_PTHREADS
+#include <pthread.h>
+#endif
+
+#ifdef RT_USING_DFS
+#include <dfs_posix.h>
+
+#ifdef RT_USING_DFS_DEVFS
+#include <devfs.h>
+#endif
+
+#endif
+
+int libc_system_init(void)
+{
+#ifdef RT_USING_DFS
+    int fd;
+    struct rt_device *console_dev;
+
+#ifndef RT_USING_DFS_DEVFS
+#error Please enable devfs by defining RT_USING_DFS_DEVFS in rtconfig.h
+#endif
+
+    console_dev = rt_console_get_device();
+    if (console_dev)
+    {
+        /* initialize console device */
+        rt_console_init(console_dev->parent.name);
+
+        /* open console as stdin/stdout/stderr */
+        fd = open("/dev/console", O_RDONLY, 0); /* for stdin */
+        fd = open("/dev/console", O_WRONLY, 0); /* for stdout */
+        fd = open("/dev/console", O_WRONLY, 0); /* for stderr */
+
+        /* skip warning */
+        fd = fd;
+    }
+#endif
+
+    /* set PATH and HOME */
+    putenv("PATH=/bin");
+    putenv("HOME=/home");
+#if defined RT_USING_PTHREADS && !defined RT_USING_COMPONENTS_INIT
+    pthread_system_init();
+#endif
+
+    return 0;
+}
+INIT_COMPONENT_EXPORT(libc_system_init);