Fix HINCRBYFLOAT to work with long doubles.

During the refactoring needed for lazy free, specifically the conversion
of t_hash from struct robj to plain SDS strings, HINCRBFLOAT was
accidentally moved away from long doubles to doubles for internal
processing of increments and formatting.

The diminished precision created more obvious artifacts in the way small
numbers are formatted once we convert from decimal number in radix 10 to
double and back to its string in radix 10.

By using more precision, we now have less surprising results at least
with small numbers like "1.23", exactly like in the previous versions of
Redis.

See issue #2846.
This commit is contained in:
antirez 2015-11-04 17:16:34 +01:00
parent f6255703b0
commit 71aa9b75f2
3 changed files with 8 additions and 8 deletions

View File

@ -596,23 +596,23 @@ void hincrbyCommand(client *c) {
} }
void hincrbyfloatCommand(client *c) { void hincrbyfloatCommand(client *c) {
double value, incr; long double value, incr;
long long ll; long long ll;
robj *o; robj *o;
sds new; sds new;
unsigned char *vstr; unsigned char *vstr;
unsigned int vlen; unsigned int vlen;
if (getDoubleFromObjectOrReply(c,c->argv[3],&incr,NULL) != C_OK) return; if (getLongDoubleFromObjectOrReply(c,c->argv[3],&incr,NULL) != C_OK) return;
if ((o = hashTypeLookupWriteOrCreate(c,c->argv[1])) == NULL) return; if ((o = hashTypeLookupWriteOrCreate(c,c->argv[1])) == NULL) return;
if (hashTypeGetValue(o,c->argv[2]->ptr,&vstr,&vlen,&ll) == C_OK) { if (hashTypeGetValue(o,c->argv[2]->ptr,&vstr,&vlen,&ll) == C_OK) {
if (vstr) { if (vstr) {
if (string2d((char*)vstr,vlen,&value) == 0) { if (string2ld((char*)vstr,vlen,&value) == 0) {
addReplyError(c,"hash value is not a float"); addReplyError(c,"hash value is not a float");
return; return;
} }
} else { } else {
value = (double)ll; value = (long double)ll;
} }
} else { } else {
value = 0; value = 0;

View File

@ -426,9 +426,9 @@ int string2l(const char *s, size_t slen, long *lval) {
* Note that this function demands that the string strictly represents * Note that this function demands that the string strictly represents
* a double: no spaces or other characters before or after the string * a double: no spaces or other characters before or after the string
* representing the number are accepted. */ * representing the number are accepted. */
int string2d(const char *s, size_t slen, double *dp) { int string2ld(const char *s, size_t slen, long double *dp) {
char buf[256]; char buf[256];
double value; long double value;
char *eptr; char *eptr;
if (slen >= sizeof(buf)) return 0; if (slen >= sizeof(buf)) return 0;
@ -436,7 +436,7 @@ int string2d(const char *s, size_t slen, double *dp) {
buf[slen] = '\0'; buf[slen] = '\0';
errno = 0; errno = 0;
value = strtod(buf, &eptr); value = strtold(buf, &eptr);
if (isspace(buf[0]) || eptr[0] != '\0' || if (isspace(buf[0]) || eptr[0] != '\0' ||
(errno == ERANGE && (errno == ERANGE &&
(value == HUGE_VAL || value == -HUGE_VAL || value == 0)) || (value == HUGE_VAL || value == -HUGE_VAL || value == 0)) ||

View File

@ -41,7 +41,7 @@ uint32_t sdigits10(int64_t v);
int ll2string(char *s, size_t len, long long value); int ll2string(char *s, size_t len, long long value);
int string2ll(const char *s, size_t slen, long long *value); int string2ll(const char *s, size_t slen, long long *value);
int string2l(const char *s, size_t slen, long *value); int string2l(const char *s, size_t slen, long *value);
int string2d(const char *s, size_t slen, double *dp); int string2ld(const char *s, size_t slen, long double *dp);
int d2string(char *buf, size_t len, double value); int d2string(char *buf, size_t len, double value);
int ld2string(char *buf, size_t len, long double value, int humanfriendly); int ld2string(char *buf, size_t len, long double value, int humanfriendly);
sds getAbsolutePath(char *filename); sds getAbsolutePath(char *filename);