--- a/libtommath/bn_mp_fread.c	Wed Feb 28 22:11:39 2018 +0800
+++ b/libtommath/bn_mp_fread.c	Thu Oct 15 19:55:15 2020 +0800
@@ -1,69 +1,60 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
 #ifdef BN_MP_FREAD_C
-/* LibTomMath, multiple-precision integer library -- Tom St Denis
- *
- * LibTomMath is a library that provides multiple-precision
- * integer arithmetic as well as number theoretic functionality.
- *
- * The library was designed directly after the MPI library by
- * Michael Fromberger but has been written from scratch with
- * additional optimizations in place.
- *
- * The library is free for all purposes without any express
- * guarantee it works.
- *
- * Tom St Denis, [email protected], http://libtom.org
- */
+/* LibTomMath, multiple-precision integer library -- Tom St Denis */
+/* SPDX-License-Identifier: Unlicense */
 
-#ifndef LTM_NO_FILE
+#ifndef MP_NO_FILE
 /* read a bigint from a file stream in ASCII */
-int mp_fread(mp_int *a, int radix, FILE *stream)
+mp_err mp_fread(mp_int *a, int radix, FILE *stream)
 {
-   int err, ch, neg, y;
-   
-   /* clear a */
-   mp_zero(a);
-   
+   mp_err err;
+   mp_sign neg;
+
    /* if first digit is - then set negative */
-   ch = fgetc(stream);
-   if (ch == '-') {
+   int ch = fgetc(stream);
+   if (ch == (int)'-') {
       neg = MP_NEG;
       ch = fgetc(stream);
    } else {
       neg = MP_ZPOS;
    }
-   
-   for (;;) {
-      /* find y in the radix map */
-      for (y = 0; y < radix; y++) {
-          if (mp_s_rmap[y] == ch) {
-             break;
-          }
-      }
-      if (y == radix) {
+
+   /* no digits, return error */
+   if (ch == EOF) {
+      return MP_ERR;
+   }
+
+   /* clear a */
+   mp_zero(a);
+
+   do {
+      int y;
+      unsigned pos = (unsigned)(ch - (int)'(');
+      if (mp_s_rmap_reverse_sz < pos) {
          break;
       }
-      
+
+      y = (int)mp_s_rmap_reverse[pos];
+
+      if ((y == 0xff) || (y >= radix)) {
+         break;
+      }
+
       /* shift up and add */
-      if ((err = mp_mul_d(a, radix, a)) != MP_OKAY) {
-         return err;
-      }
-      if ((err = mp_add_d(a, y, a)) != MP_OKAY) {
+      if ((err = mp_mul_d(a, (mp_digit)radix, a)) != MP_OKAY) {
          return err;
       }
-      
-      ch = fgetc(stream);
-   }
-   if (mp_cmp_d(a, 0) != MP_EQ) {
+      if ((err = mp_add_d(a, (mp_digit)y, a)) != MP_OKAY) {
+         return err;
+      }
+   } while ((ch = fgetc(stream)) != EOF);
+
+   if (a->used != 0) {
       a->sign = neg;
    }
-   
+
    return MP_OKAY;
 }
 #endif
 
 #endif
-
-/* ref:         $Format:%D$ */
-/* git commit:  $Format:%H$ */
-/* commit time: $Format:%ai$ */