summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorDenys Vlasenko2018-12-21 22:36:04 +0100
committerDenys Vlasenko2018-12-21 22:36:04 +0100
commite8e7bda63aeefb17b59718baca592246e24d04df (patch)
tree2816d299f0e2531e628be62c5891b9086d86eb7b
parent6ed7fb0a877d550428cb289feb3695dcd2812ab8 (diff)
downloadbusybox-e8e7bda63aeefb17b59718baca592246e24d04df.zip
busybox-e8e7bda63aeefb17b59718baca592246e24d04df.tar.gz
bc: use non-allocated BcNum's where appropriate
function old new delta zbc_num_printNum 540 543 +3 zdc_program_asciify 407 403 -4 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 1/1 up/down: 3/-4) Total: -1 bytes Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
-rw-r--r--miscutils/bc.c33
1 files changed, 18 insertions, 15 deletions
diff --git a/miscutils/bc.c b/miscutils/bc.c
index abedbdf..58e3bcb 100644
--- a/miscutils/bc.c
+++ b/miscutils/bc.c
@@ -1454,6 +1454,14 @@ static BC_STATUS zbc_num_ulong(BcNum *n, unsigned long *result_p)
}
#define zbc_num_ulong(...) (zbc_num_ulong(__VA_ARGS__) COMMA_SUCCESS)
+#if ULONG_MAX == 0xffffffffUL // 10 digits: 4294967295
+# define ULONG_NUM_BUFSIZE (10 > BC_NUM_DEF_SIZE ? 10 : BC_NUM_DEF_SIZE)
+#elif ULONG_MAX == 0xffffffffffffffffULL // 20 digits: 18446744073709551615
+# define ULONG_NUM_BUFSIZE (20 > BC_NUM_DEF_SIZE ? 20 : BC_NUM_DEF_SIZE)
+#endif
+// minimum BC_NUM_DEF_SIZE, so that bc_num_expand() in bc_num_ulong2num()
+// would not hit realloc() code path - not good if num[] is not malloced
+
static void bc_num_ulong2num(BcNum *n, unsigned long val)
{
BcDig *ptr;
@@ -1462,11 +1470,7 @@ static void bc_num_ulong2num(BcNum *n, unsigned long val)
if (val == 0) return;
- if (ULONG_MAX == 0xffffffffUL)
- bc_num_expand(n, 10); // 10 digits: 4294967295
- if (ULONG_MAX == 0xffffffffffffffffULL)
- bc_num_expand(n, 20); // 20 digits: 18446744073709551615
- BUILD_BUG_ON(ULONG_MAX > 0xffffffffffffffffULL);
+ bc_num_expand(n, ULONG_NUM_BUFSIZE);
ptr = n->num;
for (;;) {
@@ -1645,7 +1649,6 @@ static BC_STATUS zbc_num_shift(BcNum *n, size_t places)
static BC_STATUS zbc_num_inv(BcNum *a, BcNum *b, size_t scale)
{
-//TODO: nice example of non-allocated BcNum, use in other places as well!
BcNum one;
BcDig num[2];
@@ -2264,6 +2267,7 @@ static void bc_num_parseBase(BcNum *n, const char *val, unsigned base_t)
BcStatus s;
BcNum temp, mult, result;
BcNum base;
+ BcDig base_digs[ULONG_NUM_BUFSIZE];
BcDig c = '\0';
unsigned long v;
size_t i, digits;
@@ -2277,8 +2281,8 @@ static void bc_num_parseBase(BcNum *n, const char *val, unsigned base_t)
bc_num_init_DEF_SIZE(&temp);
bc_num_init_DEF_SIZE(&mult);
-//TODO: have BcNumSmall type, with static buffer
- bc_num_init_DEF_SIZE(&base);
+ base.cap = ARRAY_SIZE(base_digs);
+ base.num = base_digs;
bc_num_ulong2num(&base, base_t);
for (;;) {
@@ -2329,7 +2333,6 @@ static void bc_num_parseBase(BcNum *n, const char *val, unsigned base_t)
err:
bc_num_free(&result);
int_err:
- bc_num_free(&base);
bc_num_free(&mult);
bc_num_free(&temp);
}
@@ -5430,6 +5433,7 @@ static BC_STATUS zbc_num_printNum(BcNum *n, unsigned base_t, size_t width, BcNum
BcStatus s;
BcVec stack;
BcNum base;
+ BcDig base_digs[ULONG_NUM_BUFSIZE];
BcNum intp, fracp, digit, frac_len;
unsigned long dig, *ptr;
size_t i;
@@ -5447,8 +5451,8 @@ static BC_STATUS zbc_num_printNum(BcNum *n, unsigned base_t, size_t width, BcNum
bc_num_init(&frac_len, BC_NUM_INT(n));
bc_num_copy(&intp, n);
bc_num_one(&frac_len);
-//TODO: have BcNumSmall type, with static buffer
- bc_num_init_DEF_SIZE(&base);
+ base.cap = ARRAY_SIZE(base_digs);
+ base.num = base_digs;
bc_num_ulong2num(&base, base_t);
bc_num_truncate(&intp, intp.rdx);
@@ -5483,7 +5487,6 @@ static BC_STATUS zbc_num_printNum(BcNum *n, unsigned base_t, size_t width, BcNum
if (s) goto err;
}
err:
- bc_num_free(&base);
bc_num_free(&frac_len);
bc_num_free(&digit);
bc_num_free(&fracp);
@@ -6206,16 +6209,16 @@ static BC_STATUS zdc_program_asciify(void)
if (BC_PROG_NUM(r, num)) {
BcNum strmb;
+ BcDig strmb_digs[ULONG_NUM_BUFSIZE];
bc_num_init_DEF_SIZE(&n);
bc_num_copy(&n, num);
bc_num_truncate(&n, n.rdx);
-//TODO: have BcNumSmall type, with static buffer
- bc_num_init_DEF_SIZE(&strmb);
+ strmb.cap = ARRAY_SIZE(strmb_digs);
+ strmb.num = strmb_digs;
bc_num_ulong2num(&strmb, 0x100);
s = zbc_num_mod(&n, &strmb, &n, 0);
- bc_num_free(&strmb);
if (s) goto num_err;
s = zbc_num_ulong(&n, &val);