Add comments about why errno is set to zero.

diff --git a/src/backend/utils/adt/datetime.c b/src/backend/utils/adt/datetime.c
index e891804ece976482b66b1d617ff888af0cd047bd..ac18ec742950c01caf1939fdb7f3ebfabbeb6fca 100644 (file)
--- a/src/backend/utils/adt/datetime.c
+++ b/src/backend/utils/adt/datetime.c
@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *   $PostgreSQL: pgsql/src/backend/utils/adt/datetime.c,v 1.162 2005/12/01 17:56:34 tgl Exp $
+ *   $PostgreSQL: pgsql/src/backend/utils/adt/datetime.c,v 1.163 2005/12/01 20:06:37 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1013,7 +1013,7 @@ DecodeDateTime(char **field, int *ftype, int nf,
                    if (tzp == NULL)
                        return DTERR_BAD_FORMAT;
 
-                   errno = 0;
+                   errno = 0;  /* avoid checking LONG_MIN/LONG_MAX */
                    val = strtol(field[i], &cp, 10);
                    if (errno == ERANGE)
                        return DTERR_FIELD_OVERFLOW;
@@ -1161,7 +1161,7 @@ DecodeDateTime(char **field, int *ftype, int nf,
                    char       *cp;
                    int         val;
 
-                   errno = 0;
+                   errno = 0;  /* avoid checking LONG_MIN/LONG_MAX */
                    val = strtol(field[i], &cp, 10);
                    if (errno == ERANGE)
                        return DTERR_FIELD_OVERFLOW;
@@ -1921,7 +1921,7 @@ DecodeTimeOnly(char **field, int *ftype, int nf,
                            break;
                    }
 
-                   errno = 0;
+                   errno = 0;  /* avoid checking LONG_MIN/LONG_MAX */
                    val = strtol(field[i], &cp, 10);
                    if (errno == ERANGE)
                        return DTERR_FIELD_OVERFLOW;
@@ -2465,14 +2465,14 @@ DecodeTime(char *str, int fmask, int *tmask, struct pg_tm * tm, fsec_t *fsec)
 
    *tmask = DTK_TIME_M;
 
-   errno = 0;
+   errno = 0;  /* avoid checking LONG_MIN/LONG_MAX */
    tm->tm_hour = strtol(str, &cp, 10);
    if (errno == ERANGE)
        return DTERR_FIELD_OVERFLOW;
    if (*cp != ':')
        return DTERR_BAD_FORMAT;
    str = cp + 1;
-   errno = 0;
+   errno = 0;  /* avoid checking LONG_MIN/LONG_MAX */
    tm->tm_min = strtol(str, &cp, 10);
    if (errno == ERANGE)
        return DTERR_FIELD_OVERFLOW;
@@ -2486,7 +2486,7 @@ DecodeTime(char *str, int fmask, int *tmask, struct pg_tm * tm, fsec_t *fsec)
    else
    {
        str = cp + 1;
-       errno = 0;
+       errno = 0;  /* avoid checking LONG_MIN/LONG_MAX */
        tm->tm_sec = strtol(str, &cp, 10);
        if (errno == ERANGE)
            return DTERR_FIELD_OVERFLOW;
@@ -2540,7 +2540,7 @@ DecodeNumber(int flen, char *str, bool haveTextMonth, int fmask,
 
    *tmask = 0;
 
-   errno = 0;
+   errno = 0;  /* avoid checking LONG_MIN/LONG_MAX */
    val = strtol(str, &cp, 10);
    if (errno == ERANGE)
        return DTERR_FIELD_OVERFLOW;
@@ -2830,7 +2830,7 @@ DecodeTimezone(char *str, int *tzp)
    if (*str != '+' && *str != '-')
        return DTERR_BAD_FORMAT;
 
-   errno = 0;
+   errno = 0;  /* avoid checking LONG_MIN/LONG_MAX */
    hr = strtol(str + 1, &cp, 10);
    if (errno == ERANGE)
        return DTERR_TZDISP_OVERFLOW;
@@ -2838,7 +2838,7 @@ DecodeTimezone(char *str, int *tzp)
    /* explicit delimiter? */
    if (*cp == ':')
    {
-       errno = 0;
+       errno = 0;  /* avoid checking LONG_MIN/LONG_MAX */
        min = strtol(cp + 1, &cp, 10);
        if (errno == ERANGE)
            return DTERR_TZDISP_OVERFLOW;
@@ -3085,7 +3085,7 @@ DecodeInterval(char **field, int *ftype, int nf, int *dtype, struct pg_tm * tm,
 
            case DTK_DATE:
            case DTK_NUMBER:
-               errno = 0;
+               errno = 0;  /* avoid checking LONG_MIN/LONG_MAX */
                val = strtol(field[i], &cp, 10);
                if (errno == ERANGE)
                    return DTERR_FIELD_OVERFLOW;

diff --git a/src/backend/utils/adt/float.c b/src/backend/utils/adt/float.c
index f77c54f9cca83f8747dc835335edbc491ddbbd4c..62afe852f4bc888609e74e30bdfd9cbc29d3bbef 100644 (file)
--- 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 1.116 2005/11/17 22:14:52 tgl Exp $
+ *   $PostgreSQL: pgsql/src/backend/utils/adt/float.c,v 1.117 2005/12/01 20:06:37 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -278,7 +278,7 @@ float4in(PG_FUNCTION_ARGS)
    while (*num != '\0' && isspace((unsigned char) *num))
        num++;
 
-   errno = 0;
+   errno = 0;  /* avoid checking HUGE_VAL */
    val = strtod(num, &endptr);
 
    /* did we not see anything that looks like a double? */
@@ -445,7 +445,7 @@ float8in(PG_FUNCTION_ARGS)
    while (*num != '\0' && isspace((unsigned char) *num))
        num++;
 
-   errno = 0;
+   errno = 0;  /* avoid checking HUGE_VAL */
    val = strtod(num, &endptr);
 
    /* did we not see anything that looks like a double? */
@@ -1476,7 +1476,7 @@ dpow(PG_FUNCTION_ARGS)
     * We must check both for errno getting set and for a NaN result, in order
     * to deal with the vagaries of different platforms...
     */
-   errno = 0;
+   errno = 0;  /* avoid checking result for failure */
    result = pow(arg1, arg2);
    if (errno != 0
 #ifdef HAVE_FINITE
@@ -1506,7 +1506,7 @@ dexp(PG_FUNCTION_ARGS)
     * to deal with the vagaries of different platforms. Also, a zero result
     * implies unreported underflow.
     */
-   errno = 0;
+   errno = 0;  /* avoid checking result for failure */
    result = exp(arg1);
    if (errno != 0 || result == 0.0
 #ifdef HAVE_FINITE
@@ -1590,7 +1590,7 @@ dacos(PG_FUNCTION_ARGS)
    float8      arg1 = PG_GETARG_FLOAT8(0);
    float8      result;
 
-   errno = 0;
+   errno = 0;  /* avoid checking result for failure */
    result = acos(arg1);
    if (errno != 0
 #ifdef HAVE_FINITE
@@ -1615,7 +1615,7 @@ dasin(PG_FUNCTION_ARGS)
    float8      arg1 = PG_GETARG_FLOAT8(0);
    float8      result;
 
-   errno = 0;
+   errno = 0;  /* avoid checking result for failure */
    result = asin(arg1);
    if (errno != 0
 #ifdef HAVE_FINITE
@@ -1640,7 +1640,7 @@ datan(PG_FUNCTION_ARGS)
    float8      arg1 = PG_GETARG_FLOAT8(0);
    float8      result;
 
-   errno = 0;
+   errno = 0;  /* avoid checking result for failure */
    result = atan(arg1);
    if (errno != 0
 #ifdef HAVE_FINITE
@@ -1666,7 +1666,7 @@ datan2(PG_FUNCTION_ARGS)
    float8      arg2 = PG_GETARG_FLOAT8(1);
    float8      result;
 
-   errno = 0;
+   errno = 0;  /* avoid checking result for failure */
    result = atan2(arg1, arg2);
    if (errno != 0
 #ifdef HAVE_FINITE
@@ -1691,7 +1691,7 @@ dcos(PG_FUNCTION_ARGS)
    float8      arg1 = PG_GETARG_FLOAT8(0);
    float8      result;
 
-   errno = 0;
+   errno = 0;  /* avoid checking result for failure */
    result = cos(arg1);
    if (errno != 0
 #ifdef HAVE_FINITE
@@ -1716,7 +1716,7 @@ dcot(PG_FUNCTION_ARGS)
    float8      arg1 = PG_GETARG_FLOAT8(0);
    float8      result;
 
-   errno = 0;
+   errno = 0;  /* avoid checking result for failure */
    result = tan(arg1);
    if (errno != 0 || result == 0.0
 #ifdef HAVE_FINITE
@@ -1742,7 +1742,7 @@ dsin(PG_FUNCTION_ARGS)
    float8      arg1 = PG_GETARG_FLOAT8(0);
    float8      result;
 
-   errno = 0;
+   errno = 0;  /* avoid checking result for failure */
    result = sin(arg1);
    if (errno != 0
 #ifdef HAVE_FINITE
@@ -1767,7 +1767,7 @@ dtan(PG_FUNCTION_ARGS)
    float8      arg1 = PG_GETARG_FLOAT8(0);
    float8      result;
 
-   errno = 0;
+   errno = 0;  /* avoid checking result for failure */
    result = tan(arg1);
    if (errno != 0
 #ifdef HAVE_FINITE