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Diffstat (limited to 'src/backend/utils/adt/float.c')
-rw-r--r--src/backend/utils/adt/float.c223
1 files changed, 157 insertions, 66 deletions
diff --git a/src/backend/utils/adt/float.c b/src/backend/utils/adt/float.c
index aed643d862b..9e078bfb349 100644
--- a/src/backend/utils/adt/float.c
+++ b/src/backend/utils/adt/float.c
@@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
- * $PostgreSQL: pgsql/src/backend/utils/adt/float.c,v 1.99 2004/03/12 00:25:40 neilc Exp $
+ * $PostgreSQL: pgsql/src/backend/utils/adt/float.c,v 1.100 2004/03/14 05:22:52 neilc Exp $
*
*-------------------------------------------------------------------------
*/
@@ -109,9 +109,30 @@ int extra_float_digits = 0; /* Added to DBL_DIG or FLT_DIG */
static void CheckFloat4Val(double val);
static void CheckFloat8Val(double val);
+static int is_infinite(double val);
static int float4_cmp_internal(float4 a, float4 b);
static int float8_cmp_internal(float8 a, float8 b);
+/*
+ * Returns -1 if 'val' represents negative infinity, 1 if 'val'
+ * represents (positive) infinity, and 0 otherwise. On some platforms,
+ * this is equivalent to the isinf() macro, but not everywhere: C99
+ * does not specify that isinf() needs to distinguish between positive
+ * and negative infinity.
+ */
+static int
+is_infinite(double val)
+{
+ int inf = isinf(val);
+
+ if (inf == 0)
+ return 0;
+
+ if (val > 0)
+ return 1;
+
+ return -1;
+}
/*
* check to see if a float4 val is outside of the FLOAT4_MIN,
@@ -162,48 +183,78 @@ Datum
float4in(PG_FUNCTION_ARGS)
{
char *num = PG_GETARG_CSTRING(0);
+ char *orig_num;
double val;
char *endptr;
+ /*
+ * endptr points to the first character _after_ the sequence we
+ * recognized as a valid floating point number. orig_num points to
+ * the original input string.
+ */
+ orig_num = num;
+
+ /*
+ * Check for an empty-string input to begin with, to avoid
+ * the vagaries of strtod() on different platforms.
+ *
+ * In releases prior to 7.5, we accepted an empty string as valid
+ * input (yielding a float4 of 0). In 7.5, we accept empty
+ * strings, but emit a warning noting that the feature is
+ * deprecated. In 7.6+, the warning should be replaced by an
+ * error.
+ */
+ if (*num == '\0')
+ {
+ ereport(WARNING,
+ (errcode(ERRCODE_WARNING_DEPRECATED_FEATURE),
+ errmsg("deprecated input syntax for type real: \"\""),
+ errdetail("This input will be rejected in "
+ "a future release of PostgreSQL.")));
+ PG_RETURN_FLOAT4((float4) 0.0);
+ }
+
+ /* skip leading whitespace */
+ while (*num != '\0' && isspace(*num))
+ num++;
+
errno = 0;
val = strtod(num, &endptr);
if (errno == ERANGE)
ereport(ERROR,
(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
- errmsg("\"%s\" is out of range for type real", num)));
+ errmsg("\"%s\" is out of range for type real",
+ orig_num)));
+ /* did we not see anything that looks like a double? */
if (num == endptr)
{
/*
- * We didn't find anything that looks like a float in the input
- *
- * In releases prior to 7.5, we accepted an empty string as
- * valid input (yielding a float8 of 0). In 7.5, we accept
- * empty strings, but emit a warning noting that the feature
- * is deprecated. In 7.6+, the warning should be replaced by
- * an error.
+ * C99 requires that strtod() accept NaN and [-]Infinity, but
+ * not all platforms support that yet. Therefore, we check for
+ * these inputs ourselves.
*/
- if (*num == '\0')
+ if (strncasecmp(num, "NaN", 3) == 0)
{
- ereport(WARNING,
- (errcode(ERRCODE_WARNING_DEPRECATED_FEATURE),
- errmsg("deprecated input syntax for type real: \"\""),
- errdetail("This input will be rejected in "
- "a future release of PostgreSQL.")));
- Assert(val == 0.0);
- }
- else if (strcasecmp(num, "NaN") == 0)
val = NAN;
- else if (strcasecmp(num, "Infinity") == 0)
+ endptr = num + 3;
+ }
+ else if (strncasecmp(num, "Infinity", 8) == 0)
+ {
val = HUGE_VAL;
- else if (strcasecmp(num, "-Infinity") == 0)
+ endptr = num + 8;
+ }
+ else if (strncasecmp(num, "-Infinity", 9) == 0)
+ {
val = -HUGE_VAL;
+ endptr = num + 9;
+ }
else
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type real: \"%s\"",
- num)));
+ orig_num)));
}
/* skip trailing whitespace */
@@ -215,11 +266,11 @@ float4in(PG_FUNCTION_ARGS)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type real: \"%s\"",
- num)));
+ orig_num)));
/*
* if we get here, we have a legal double, still need to check to see
- * if it's a legal float
+ * if it's a legal float4
*/
if (!isinf(val))
CheckFloat4Val(val);
@@ -236,22 +287,27 @@ float4out(PG_FUNCTION_ARGS)
{
float4 num = PG_GETARG_FLOAT4(0);
char *ascii = (char *) palloc(MAXFLOATWIDTH + 1);
- int infflag;
- int ndig;
if (isnan(num))
PG_RETURN_CSTRING(strcpy(ascii, "NaN"));
- infflag = isinf(num);
- if (infflag > 0)
- PG_RETURN_CSTRING(strcpy(ascii, "Infinity"));
- if (infflag < 0)
- PG_RETURN_CSTRING(strcpy(ascii, "-Infinity"));
- ndig = FLT_DIG + extra_float_digits;
- if (ndig < 1)
- ndig = 1;
+ switch (is_infinite(num))
+ {
+ case 1:
+ strcpy(ascii, "Infinity");
+ break;
+ case -1:
+ strcpy(ascii, "-Infinity");
+ break;
+ default:
+ {
+ int ndig = FLT_DIG + extra_float_digits;
+ if (ndig < 1)
+ ndig = 1;
- sprintf(ascii, "%.*g", ndig, num);
+ sprintf(ascii, "%.*g", ndig, num);
+ }
+ }
PG_RETURN_CSTRING(ascii);
}
@@ -292,48 +348,78 @@ Datum
float8in(PG_FUNCTION_ARGS)
{
char *num = PG_GETARG_CSTRING(0);
+ char *orig_num;
double val;
char *endptr;
+ /*
+ * endptr points to the first character _after_ the sequence we
+ * recognized as a valid floating point number. orig_num points to
+ * the original input string.
+ */
+ orig_num = num;
+
+ /*
+ * Check for an empty-string input to begin with, to avoid
+ * the vagaries of strtod() on different platforms.
+ *
+ * In releases prior to 7.5, we accepted an empty string as valid
+ * input (yielding a float8 of 0). In 7.5, we accept empty
+ * strings, but emit a warning noting that the feature is
+ * deprecated. In 7.6+, the warning should be replaced by an
+ * error.
+ */
+ if (*num == '\0')
+ {
+ ereport(WARNING,
+ (errcode(ERRCODE_WARNING_DEPRECATED_FEATURE),
+ errmsg("deprecated input syntax for type double precision: \"\""),
+ errdetail("This input will be rejected in "
+ "a future release of PostgreSQL.")));
+ PG_RETURN_FLOAT8(0.0);
+ }
+
+ /* skip leading whitespace */
+ while (*num != '\0' && isspace(*num))
+ num++;
+
errno = 0;
val = strtod(num, &endptr);
if (errno == ERANGE)
ereport(ERROR,
(errcode(ERRCODE_NUMERIC_VALUE_OUT_OF_RANGE),
- errmsg("\"%s\" is out of range for type double precision", num)));
+ errmsg("\"%s\" is out of range for type double precision",
+ orig_num)));
+ /* did we not see anything that looks like a double? */
if (num == endptr)
{
/*
- * We didn't find anything that looks like a float in the input
- *
- * In releases prior to 7.5, we accepted an empty string as
- * valid input (yielding a float8 of 0). In 7.5, we accept
- * empty strings, but emit a warning noting that the feature
- * is deprecated. In 7.6+, the warning should be replaced by
- * an error.
+ * C99 requires that strtod() accept NaN and [-]Infinity, but
+ * not all platforms support that yet. Therefore, we check for
+ * these inputs ourselves.
*/
- if (*num == '\0')
+ if (strncasecmp(num, "NaN", 3) == 0)
{
- ereport(WARNING,
- (errcode(ERRCODE_WARNING_DEPRECATED_FEATURE),
- errmsg("deprecated input syntax for type double precision: \"\""),
- errdetail("This input will be rejected in "
- "a future release of PostgreSQL.")));
- Assert(val == 0.0);
- }
- else if (strcasecmp(num, "NaN") == 0)
val = NAN;
- else if (strcasecmp(num, "Infinity") == 0)
+ endptr = num + 3;
+ }
+ else if (strncasecmp(num, "Infinity", 8) == 0)
+ {
val = HUGE_VAL;
- else if (strcasecmp(num, "-Infinity") == 0)
+ endptr = num + 8;
+ }
+ else if (strncasecmp(num, "-Infinity", 9) == 0)
+ {
val = -HUGE_VAL;
+ endptr = num + 9;
+ }
else
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type double precision: \"%s\"",
- num)));
+ orig_num)));
}
/* skip trailing whitespace */
@@ -345,7 +431,7 @@ float8in(PG_FUNCTION_ARGS)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("invalid input syntax for type double precision: \"%s\"",
- num)));
+ orig_num)));
if (!isinf(val))
CheckFloat8Val(val);
@@ -362,22 +448,27 @@ float8out(PG_FUNCTION_ARGS)
{
float8 num = PG_GETARG_FLOAT8(0);
char *ascii = (char *) palloc(MAXDOUBLEWIDTH + 1);
- int infflag;
- int ndig;
if (isnan(num))
PG_RETURN_CSTRING(strcpy(ascii, "NaN"));
- infflag = isinf(num);
- if (infflag > 0)
- PG_RETURN_CSTRING(strcpy(ascii, "Infinity"));
- if (infflag < 0)
- PG_RETURN_CSTRING(strcpy(ascii, "-Infinity"));
- ndig = DBL_DIG + extra_float_digits;
- if (ndig < 1)
- ndig = 1;
+ switch (is_infinite(num))
+ {
+ case 1:
+ strcpy(ascii, "Infinity");
+ break;
+ case -1:
+ strcpy(ascii, "-Infinity");
+ break;
+ default:
+ {
+ int ndig = DBL_DIG + extra_float_digits;
+ if (ndig < 1)
+ ndig = 1;
- sprintf(ascii, "%.*g", ndig, num);
+ sprintf(ascii, "%.*g", ndig, num);
+ }
+ }
PG_RETURN_CSTRING(ascii);
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-05-30 14:55:27 +0000