!183 [libc] add libc.a checking in musl

Merge pull request !183 from bernard/bernard_rt-smart

components/libc/compilers/musl/SConscript

@@ -1,3 +1,4 @@
+import os
 from building import *
 Import('rtconfig')
 
@@ -5,14 +6,20 @@ src = Glob('*.c')
 cwd = GetCurrentDir()
 group = []
 
-CFLAGS     = ' -nostdinc'
-CPPPATH    = [cwd, cwd + '/libc/include']
-CPPDEFINES = ['__STDC_ISO_10646__=201206L', '_STDC_PREDEF_H']
-LIBS       = ['c', 'gcc']
-LIBPATH    = [cwd + '/libc/lib']
+if rtconfig.PLATFORM == 'gcc' and GetDepend('RT_USING_MUSL'):
+    CPPDEFINES = ['__STDC_ISO_10646__=201206L', '_STDC_PREDEF_H']
+    LIBS       = ['c', 'gcc']
 
-if rtconfig.PLATFORM == 'gcc':
-    group = DefineGroup('musl', src, depend = ['RT_USING_LIBC', 'RT_USING_MUSL'], CFLAGS = CFLAGS, 
-        CPPPATH = CPPPATH, CPPDEFINES = CPPDEFINES, LIBS = LIBS, LIBPATH = LIBPATH)
+    if os.path.exists(os.path.join(cwd, 'libc', 'lib', 'libc.a')):
+        CFLAGS     = ' -nostdinc'
+        CPPPATH    = [cwd, cwd + '/libc/include']
+        LIBPATH    = [cwd + '/libc/lib']
+
+        group = DefineGroup('musl', src, depend = ['RT_USING_LIBC', 'RT_USING_MUSL'], CFLAGS = CFLAGS, 
+            CPPPATH = CPPPATH, CPPDEFINES = CPPDEFINES, LIBS = LIBS, LIBPATH = LIBPATH)
+    else:
+        LINKFLAGS = ' --specs=kernel.specs'
+        group = DefineGroup('musl', src, depend = ['RT_USING_LIBC', 'RT_USING_MUSL'], LINKFLAGS = LINKFLAGS, 
+            CPPDEFINES = CPPDEFINES, LIBS = LIBS)
 
 Return('group')

components/libc/compilers/musl/init.c

@@ -1,16 +0,0 @@
-extern char **__environ;
-
-#if 0
-void __init_libc(char **envp, char *pn)
-{
-    __environ = envp;
-}
-#endif
-
-void __libc_exit_fini(void)
-{
-}
-
-void __libc_start_init(void)
-{
-}

components/libc/compilers/musl/libc_syms.c

@@ -1,54 +0,0 @@
-/*
- * Copyright (c) 2006-2018, RT-Thread Development Team
- *
- * SPDX-License-Identifier: Apache-2.0
- *
- * Change Logs:
- * Date           Author       Notes
- * 2017/10/15     bernard      the first version
- */
-#include <rtthread.h>
-#include <rtm.h>
-
-#include <string.h>
-#include <stdio.h>
-#include <stdlib.h>
-
-RTM_EXPORT(strcpy);
-RTM_EXPORT(strncpy);
-RTM_EXPORT(strlen);
-RTM_EXPORT(strcat);
-RTM_EXPORT(strstr);
-RTM_EXPORT(strchr);
-RTM_EXPORT(strcmp);
-RTM_EXPORT(strtol);
-RTM_EXPORT(strtoul);
-RTM_EXPORT(strncmp);
-
-RTM_EXPORT(memcpy);
-RTM_EXPORT(memcmp);
-RTM_EXPORT(memmove);
-RTM_EXPORT(memset);
-RTM_EXPORT(memchr);
-
-RTM_EXPORT(putchar);
-RTM_EXPORT(puts);
-RTM_EXPORT(printf);
-RTM_EXPORT(sprintf);
-RTM_EXPORT(snprintf);
-
-RTM_EXPORT(fwrite);
-
-#include <time.h>
-RTM_EXPORT(localtime);
-RTM_EXPORT(time);
-
-#include <setjmp.h>
-RTM_EXPORT(longjmp);
-RTM_EXPORT(setjmp);
-
-RTM_EXPORT(exit);
-RTM_EXPORT(abort);
-
-RTM_EXPORT(rand);
-

components/libc/compilers/musl/stdio.c

@@ -12,7 +12,6 @@
 
 #include <rtthread.h>
 #include "libc.h"
-#include "dfs.h"
 
 #define STDIO_DEVICE_NAME_MAX   32
 
@@ -61,9 +60,13 @@ int libc_stdio_set_console(const char* device_name, int mode)
     return -1;
 }
 
-int libc_stdio_get_console(void) {
+int libc_stdio_get_console(void)
+{
+    int ret = -1;
     if (std_console)
-        return fileno(std_console);
-    else
-        return -1;
+    {
+        ret = fileno(std_console);
+    }
+
+    return ret;
 }