bc: move ^C check fro power calculation to multiplication

function                                             old     new   delta
bc_num_k                                             971     990     +19
bc_num_p                                             507     478     -29
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 1/1 up/down: 19/-29)            Total: -10 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/miscutils/bc.c b/miscutils/bc.c
index ea200ebda922884acc1235a9651066ac7fb17fa8..07793e9d413bcdcac160117a935a969897374f9d 100644 (file)
--- a/miscutils/bc.c
+++ b/miscutils/bc.c
@@ -1676,6 +1676,10 @@ static BcStatus bc_num_k(BcNum *restrict a, BcNum *restrict b,
 
                        c->num[i + j] += (BcDig) carry;
                        len = BC_MAX(len, i + j + !!carry);
+
+                       // a=2^1000000
+                       // a*a <- without check below, this will not be interruptible
+                       if (G_interrupt) return BC_STATUS_FAILURE;
                }
 
                c->len = len;
@@ -1935,11 +1939,11 @@ static BcStatus bc_num_p(BcNum *a, BcNum *b, BcNum *restrict c, size_t scale)
                powrdx <<= 1;
                s = bc_num_mul(&copy, &copy, &copy, powrdx);
                if (s) goto err;
-               // It is too slow to handle ^C only after entire "2^1000000" completes
-               if (G_interrupt) {
-                       s = BC_STATUS_FAILURE;
-                       goto err;
-               }
+               // Not needed: bc_num_mul() has a check for ^C:
+               //if (G_interrupt) {
+               //      s = BC_STATUS_FAILURE;
+               //      goto err;
+               //}
        }
 
        bc_num_copy(c, &copy);
@@ -1955,11 +1959,11 @@ static BcStatus bc_num_p(BcNum *a, BcNum *b, BcNum *restrict c, size_t scale)
                        s = bc_num_mul(c, &copy, c, resrdx);
                        if (s) goto err;
                }
-               // It is too slow to handle ^C only after entire "2^1000000" completes
-               if (G_interrupt) {
-                       s = BC_STATUS_FAILURE;
-                       goto err;
-               }
+               // Not needed: bc_num_mul() has a check for ^C:
+               //if (G_interrupt) {
+               //      s = BC_STATUS_FAILURE;
+               //      goto err;
+               //}
        }
 
        if (neg) {