Previously this was returning two values, a 'bool' and a data
structure that is created. Now it simply returns the data
structure which makes it easier to reason about who takes
ownership of the memory and when, also that no address-of can
be supplied that has any side-effect that interacts with how
the method works / the returned result.
-extern bool CIFParsePath(CIFPath **pathheadpp, int iscale);
+extern CIFPath *CIFParsePath(int iscale);
Previous related comments:
Easier to reason about, there can be no interaction from *pathheadpp
and the various functions called, which maybe the first concern to
the next reader as visibility of new data is limited to that of a
local variable of the function.
The type is actually an enum (assumed to be int by default) but relies
on the magic typedef to (unsigned char) so we make this explicit and
better document what the real type is.
I guess in the past it was really a bool with only 2 states NONE|TEXT.
C29 bool type compatibility
The data types CIFPath and CIFReadStyle are part of CIFread.h
and all users outside include CIFread.h already.
K&R obsolete syntax removal for C23 compatibility series
no way to implement boolean operators on labels, so any "label"
statement in the section can apply only to one magic layer. This
is regularly violated in most (all?) techfiles (due mainly to lack
of explanation and guidance). The addition of the "no-reconnect-
labels" option for cifinput made it worse, as it can cause a label
to be attached to the wrong layer and be stuck that way. Even
without the option, an attachment to a non-connecting type is a
problem; DIFF cannot simultaneously have a connection to both
ndiff and pdiff, so it will be one or the other, and the one not
connected can easily get labels moved to other nets. To avoid
this: (1) removed the "no-reconnect-labels" option, and (2) made
the automatic label reconnection smarter, as well as splitting it
into two different behaviors based on whether a label is being
created or manipulated from the command line (more or less the
original behavior) vs. being read from GDS or LEF. The new rules
assume that labels attached to a GDS type will all map to the
same plane in magic. To avoid excessive error messages from
existing tech files, a warning is issued only if "labels" changes
the plane of the target layer (a realistic solution rather than
the preferred one). Also: Fixed an error that causes a crash on
the "wizard" command "*watch" if the cell being observed is
read-only (see github issue #271).
option "labels ... cellid" to handle some vendor files where
apparently to get around the 30-character cell name limit, the
actual cellname is encoded on a text layer. Added new cifop
"boundary" (no arguments) for cases where a cell abutment box
is encoded on a GDS layer; this now translates the bounding
box to the FIXED_BBOX property, as is done with the LEF bounding
box. Also corrected the property set function to free existing
property value allocated memory when overwriting a property with
a new value.
development had been halted since it was first created back in April.
Version 8.2 is now the official development version, with the first
development push to create a Cairo graphics interface.
Darryl L. Miles
Tim Edwards