From 4557ddddb1e8acb4405375a18f58f6363e13d5e3 Mon Sep 17 00:00:00 2001
From: Jan Nieuwenhuizen <janneke@gnu.org>
Date: Sun, 20 Oct 2019 19:28:04 +0200
Subject: [PATCH] mescc: Mes C Library: Prepare for M2-Planet: fdgetc.

* lib/mes/fdgetc.c: Rewrite C-constructs not supported by M2-Planet.
---
 lib/mes/fdgetc.c | 17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/lib/mes/fdgetc.c b/lib/mes/fdgetc.c
index 74a8eaff..0370c24e 100644
--- a/lib/mes/fdgetc.c
+++ b/lib/mes/fdgetc.c
@@ -19,12 +19,14 @@
  */
 
 #include <mes/lib.h>
+#include <errno.h>
 #include <limits.h>
+#include <stdlib.h>
 #include <string.h>
 #include <sys/resource.h>
 #include <unistd.h>
 
-int __ungetc_buf[__FILEDES_MAX + 1] = { 0 };
+int *__ungetc_buf;
 
 int
 __ungetc_p (int filedes)
@@ -35,8 +37,13 @@ __ungetc_p (int filedes)
 void
 __ungetc_init ()
 {
-  if (__ungetc_buf[__FILEDES_MAX] == 0)
-    memset (__ungetc_buf, -1, (__FILEDES_MAX + 1) * sizeof (int));
+  if (__ungetc_buf == 0)
+    {
+      int save_errno = errno;
+      __ungetc_buf = malloc ((__FILEDES_MAX + 1) * sizeof (int));
+      errno = save_errno;
+      memset (__ungetc_buf, -1, (__FILEDES_MAX + 1) * sizeof (int));
+    }
 }
 
 void
@@ -65,10 +72,10 @@ fdgetc (int fd)
       int r = read (fd, &c, 1);
       if (r < 1)
         return -1;
-      i = (int) c;
+      i = c;
     }
   if (i < 0)
-    i += 256;
+    i = i + 256;
 
   return i;
 }