(sexp_vformat): For %i, output a leading zero when

needed to get a correct, positive, sign. For %b, use
nettle_mpz_sizeinbase_256_s, to handle negative numbers properly.

Rev: src/nettle/sexp-format.c:1.4

diff --git a/sexp-format.c b/sexp-format.c
index d445f0342ad87d14d2a5a8004515dbd54413f23c..217ead315acd4f256b86d25ead2b2794ccc982e1 100644 (file)
--- a/sexp-format.c
+++ b/sexp-format.c
@@ -177,15 +177,17 @@ sexp_vformat(struct nettle_buffer *buffer, const char *format, va_list args)
              uint32_t x = va_arg(args, uint32_t);
              unsigned length;
              
-             if (x < 0x100)
+             if (x < 0x80)
                length = 1;
-             else if (x < 0x10000L)
+             else if (x < 0x8000L)
                length = 2;
-             else if (x < 0x1000000L)
+             else if (x < 0x800000L)
                length = 3;
-             else
+             else if (x < 0x80000000L)
                length = 4;
-
+             else
+               length = 5;
+             
              if (buffer && !(NETTLE_BUFFER_PUTC(buffer, '0' + length)
                              && NETTLE_BUFFER_PUTC(buffer, ':')))
                return 0;
@@ -195,6 +197,11 @@ sexp_vformat(struct nettle_buffer *buffer, const char *format, va_list args)
              if (buffer)
                switch(length)
                {
+               case 5:
+                 /* Leading byte needed for the sign. */
+                 if (!NETTLE_BUFFER_PUTC(buffer, 0))
+                   return 0;
+                 /* Fall through */
                case 4:
                  if (!NETTLE_BUFFER_PUTC(buffer, x >> 24))
                    return 0;
@@ -223,9 +230,7 @@ sexp_vformat(struct nettle_buffer *buffer, const char *format, va_list args)
              unsigned length;
              unsigned prefix_length;
              
-             assert(mpz_sgn(n) >= 0);
-
-             length = nettle_mpz_sizeinbase_256(n);
+             length = nettle_mpz_sizeinbase_256_s(n);
              prefix_length = format_prefix(buffer, length);
              if (!prefix_length)
                return 0;