add in libgloss the support of the system calls "read" and "wait"

newlib/src/libgloss/metalsvm/read.c

@@ -24,6 +24,7 @@
 #undef errno
 extern int errno;
 #include "warning.h"
+#include "syscall.h"
 
 int
 _DEFUN (_read, (file, ptr, len),
@@ -31,5 +32,13 @@ _DEFUN (_read, (file, ptr, len),
         char *ptr   _AND
         int   len)
 {
-	return 0;
+	int ret;
+
+	ret = SYSCALL3(__NR_read, file, ptr, len);
+	if (ret < 0) {
+		errno = -ret;
+		ret = -1;
+	}
+
+	return ret;
 }

newlib/src/libgloss/metalsvm/syscall.h

@@ -36,6 +36,7 @@ extern "C" {
 #define __NR_fstat		10
 #define __NR_sbrk		11
 #define __NR_fork		12
+#define __NR_wait		13
 
 #define _STR(token)             #token
 #define _SYSCALLSTR(x)          "int $" _STR(x) " "

newlib/src/libgloss/metalsvm/wait.c

@@ -23,14 +23,21 @@
 #include <errno.h>
 #undef errno
 extern int errno;
+#include "syscall.h"
 #include "warning.h"
 
 int
 _DEFUN (_wait, (status),
         int  *status)
 {
-  errno = ENOSYS;
-  return -1;
-}
+	int ret;
 
-stub_warning(_wait)
+	/* create a child process */
+	ret = SYSCALL1(__NR_wait, status);
+	if (ret < 0) {
+		errno = -ret;
+		ret = -1;
+	}
+
+	return ret;
+}