Make earthdistance use version-0 calling convention if not USE_FLOAT8_BYVAL,

and version-1 if USE_FLOAT8_BYVAL.  This might seem a bit pointless, but the
idea is to have at least one regression test that will fail if we ever
accidentally break version-0 functions that return float8.  However, they're
already broken, or at least hopelessly unportable, in the USE_FLOAT8_BYVAL
case.

Per a recent suggestion from Greg Stark.
This commit is contained in:
Tom Lane 2008-04-21 01:11:43 +00:00
parent 8472bf7a73
commit 3d1588cd3e
1 changed files with 56 additions and 14 deletions

View File

@ -1,4 +1,4 @@
/* $PostgreSQL: pgsql/contrib/earthdistance/earthdistance.c,v 1.14 2008/04/20 01:05:52 tgl Exp $ */
/* $PostgreSQL: pgsql/contrib/earthdistance/earthdistance.c,v 1.15 2008/04/21 01:11:43 tgl Exp $ */
#include "postgres.h"
@ -17,10 +17,6 @@ PG_MODULE_MAGIC;
static const double EARTH_RADIUS = 3958.747716;
static const double TWO_PI = 2.0 * M_PI;
PG_FUNCTION_INFO_V1(geo_distance);
Datum geo_distance(PG_FUNCTION_ARGS);
/******************************************************
*
@ -37,26 +33,22 @@ degtorad(double degrees)
return (degrees / 360.0) * TWO_PI;
}
/******************************************************
*
* geo_distance - distance between points
* geo_distance_internal - distance between points
*
* args:
* a pair of points - for each point,
* x-coordinate is longitude in degrees west of Greenwich
* y-coordinate is latitude in degrees above equator
*
* returns: float8
* returns: double
* distance between the points in miles on earth's surface
******************************************************/
Datum
geo_distance(PG_FUNCTION_ARGS)
static double
geo_distance_internal(Point *pt1, Point *pt2)
{
Point *pt1 = PG_GETARG_POINT_P(0);
Point *pt2 = PG_GETARG_POINT_P(1);
float8 result;
double long1,
lat1,
long2,
@ -81,7 +73,57 @@ geo_distance(PG_FUNCTION_ARGS)
cos(lat1) * cos(lat2) * sin(longdiff / 2.) * sin(longdiff / 2.));
if (sino > 1.)
sino = 1.;
result = 2. * EARTH_RADIUS * asin(sino);
return 2. * EARTH_RADIUS * asin(sino);
}
/******************************************************
*
* geo_distance - distance between points
*
* args:
* a pair of points - for each point,
* x-coordinate is longitude in degrees west of Greenwich
* y-coordinate is latitude in degrees above equator
*
* returns: float8
* distance between the points in miles on earth's surface
*
* If float8 is passed-by-value, the oldstyle version-0 calling convention
* is unportable, so we use version-1. However, if it's passed-by-reference,
* continue to use oldstyle. This is just because we'd like earthdistance
* to serve as a canary for any unintentional breakage of version-0 functions
* with float8 results.
******************************************************/
#ifdef USE_FLOAT8_BYVAL
Datum geo_distance(PG_FUNCTION_ARGS);
PG_FUNCTION_INFO_V1(geo_distance);
Datum
geo_distance(PG_FUNCTION_ARGS)
{
Point *pt1 = PG_GETARG_POINT_P(0);
Point *pt2 = PG_GETARG_POINT_P(1);
float8 result;
result = geo_distance_internal(pt1, pt2);
PG_RETURN_FLOAT8(result);
}
#else /* !USE_FLOAT8_BYVAL */
double *geo_distance(Point *pt1, Point *pt2);
double *
geo_distance(Point *pt1, Point *pt2)
{
double *resultp = palloc(sizeof(double));
*resultp = geo_distance_internal(pt1, pt2);
return resultp;
}
#endif /* USE_FLOAT8_BYVAL */