[libredwg] LibreDWG review

[Pero Brbora]

this is LibreDWG review.

MACROS

Macros are both usefull and evil. Maybe its time to convert macros to  
functions (one file for each object/entity for example).

Usefull command line:
---
gcc -I. -E -P -C $f | sed '/^\#/d' | indent > demacro-$f
---
which expands macros, leaves comments, inserts headers verbatim,  
removes line marks (sed) and indents code is a good start.

After I read resulting files, noticed that logging is not enabled in  
bits.c because DWG_LOGLEVEL is not defined before including logging.h  
header.


BITCODE TYPES

Some bitcode types are defined as unsigned (bitshort for example).  
This is not by the specification.  Functions returning bitcode types  
should follow those types (currently not the case).

Note that everything can be done with only three basic C types: char,  
int and double. Also consider using stdint.h.


MEMORY

Dwg free API function only frees header section!? Better memory  
handling is needed.

Consider central memory functions which then calls malloc/free. Also  
memory structure is needed to keep track of allocated memory.


MAKEFILE

GCC option -Wall is not used!? Here are some warnings when using -Wall  
option is used:
---
dwg_api.c: warning: control reaches end of non-void function
dwg_api.c: warning: 'ret_obj' may be used uninitialized in this function
---

Also what is the purpose of api.[ch] source files, they seem to be  
duplicates of dwg_api.[ch] files?


That's it for now.
Thank you, bye