database/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-07-30 16:24:05 +03:00
Code Activity

decimal_cmp()

Browse Source
This commit is contained in:
serg@serg.mylan
2004-10-20 15:26:03 +02:00
parent 30947b7b0e
commit c593ab8e6e
2 changed files with 38 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

1
include/decimal.h
View File

@ -45,6 +45,7 @@ int decimal_result_size(decimal *from1, decimal *from2, char op, int param);
int decimal_add(decimal *from1, decimal *from2, decimal *to); int decimal_add(decimal *from1, decimal *from2, decimal *to);
int decimal_sub(decimal *from1, decimal *from2, decimal *to); int decimal_sub(decimal *from1, decimal *from2, decimal *to);
int decimal_cmp(decimal *from1, decimal *from2);
int decimal_mul(decimal *from1, decimal *from2, decimal *to); int decimal_mul(decimal *from1, decimal *from2, decimal *to);
int decimal_div(decimal *from1, decimal *from2, decimal *to, int scale_incr); int decimal_div(decimal *from1, decimal *from2, decimal *to, int scale_incr);
int decimal_mod(decimal *from1, decimal *from2, decimal *to); int decimal_mod(decimal *from1, decimal *from2, decimal *to);

40
strings/decimal.c
View File

@ -983,7 +983,8 @@ static int do_add(decimal *from1, decimal *from2, decimal *to)
return error; return error;
} }
/* to=from1-from2 */ /* to=from1-from2.
if to==0, return -1/0/+1 - the result of the comparison */
static int do_sub(decimal *from1, decimal *from2, decimal *to) static int do_sub(decimal *from1, decimal *from2, decimal *to)
{ {
int intg1=ROUND_UP(from1->intg), intg2=ROUND_UP(from2->intg), int intg1=ROUND_UP(from1->intg), intg2=ROUND_UP(from2->intg),
@ -991,8 +992,6 @@ static int do_sub(decimal *from1, decimal *from2, decimal *to)
int frac0=max(frac1, frac2), error; int frac0=max(frac1, frac2), error;
dec1 *buf1, *buf2, *buf0, *stop1, *stop2, *start1, *start2, carry=0; dec1 *buf1, *buf2, *buf0, *stop1, *stop2, *start1, *start2, carry=0;
to->sign=from1->sign;
/* let carry:=1 if from2 > from1 */ /* let carry:=1 if from2 > from1 */
start1=buf1=from1->buf; stop1=buf1+intg1; start1=buf1=from1->buf; stop1=buf1+intg1;
start2=buf2=from2->buf; stop2=buf2+intg2; start2=buf2=from2->buf; stop2=buf2+intg2;
@ -1026,10 +1025,18 @@ static int do_sub(decimal *from1, decimal *from2, decimal *to)
carry=1; carry=1;
else /* short-circuit everything: from1 == from2 */ else /* short-circuit everything: from1 == from2 */
{ {
if (to == 0) /* decimal_cmp() */
return 0;
MAKE_ZERO(to); MAKE_ZERO(to);
return E_DEC_OK; return E_DEC_OK;
} }
} }
if (to == 0) /* decimal_cmp() */
return carry == from1->sign ? 1 : -1;
to->sign=from1->sign;
/* ensure that always from1 > from2 (and intg1 >= intg2) */ /* ensure that always from1 > from2 (and intg1 >= intg2) */
if (carry) if (carry)
{ {
@ -1109,6 +1116,13 @@ int decimal_sub(decimal *from1, decimal *from2, decimal *to)
return do_add(from1, from2, to); return do_add(from1, from2, to);
} }
int decimal_cmp(decimal *from1, decimal *from2)
{
if (likely(from1->sign == from2->sign))
return do_sub(from1, from2, 0);
return from1->sign > from2->sign ? -1 : 1;
}
/* /*
multiply two decimals multiply two decimals
@ -1685,6 +1699,17 @@ void test_ds(char *s1, char *s2)
printf("\n"); printf("\n");
} }
void test_dc(char *s1, char *s2)
{
char s[100];
int res;
sprintf(s, "'%s' <=> '%s'", s1, s2);
string2decimal(s1, &a, 0);
string2decimal(s2, &b, 0);
res=decimal_cmp(&a, &b);
printf("%-40s => res=%d\n", s, res);
}
void test_dm(char *s1, char *s2) void test_dm(char *s1, char *s2)
{ {
char s[100]; char s[100];
@ -1899,6 +1924,15 @@ main()
test_d2b2d("-.000000012345000098765", 30, 20); test_d2b2d("-.000000012345000098765", 30, 20);
test_d2b2d("1234500009876.5", 30, 5); test_d2b2d("1234500009876.5", 30, 5);
printf("==== decimal_cmp ====\n");
test_dc("12","13");
test_dc("13","12");
test_dc("-10","10");
test_dc("10","-10");
test_dc("-12","-13");
test_dc("0","12");
test_dc("-10","0");
test_dc("4","4");
return 0; return 0;
} }
#endif #endif