Formerly, the geometric I/O routines such as box_in and point_out relied
directly on strtod() and sprintf() for conversion of the float8 component
values of their data types. However, the behavior of those functions is
pretty platform-dependent, especially for edge-case values such as
infinities and NaNs. This was exposed by commit acdf2a8b37, which
added test cases involving boxes with infinity endpoints, and immediately
failed on Windows and AIX buildfarm members. We solved these problems
years ago in the main float8in and float8out functions, so let's fix it
by making the geometric types use that code instead of depending directly
on the platform-supplied functions.
To do this, refactor the float8in code so that it can be used to parse
just part of a string, and as a convenience make the guts of float8out
usable without going through DirectFunctionCall.
While at it, get rid of geo_ops.c's fairly shaky assumptions about the
maximum output string length for a double, by having it build results in
StringInfo buffers instead of fixed-length strings.
In passing, convert all the "invalid input syntax for type foo" messages
in this area of the code into "invalid input syntax for type %s" to reduce
the number of distinct translatable strings, per recent discussion.
We would have needed a fair number of the latter anyway for code-sharing
reasons, so we might as well just go whole hog.
Note: this patch is by no means intended to guarantee that the geometric
types uniformly behave sanely for infinity or NaN component values.
But any bugs we have in that line were there all along, they were just
harder to reach in a platform-independent way.
Tom Lane
50861cd683