CTF functions return zero on success or an extended errno value which
can be translated into a string via the functions in this commit.
The errno numbers start at -CTF_BASE.
libctf/
* ctf-error.c: New file.
include/
* ctf-api.h (ctf_errno): New declaration.
(ctf_errmsg): Likewise.
The memory-allocation wrappers are simple things to allow malloc
interposition: they are only used inconsistently at present, usually
where malloc debugging was required in the past.
These provide a default implementation that is environment-variable
triggered (initialized on the first call to the libctf creation and
file-opening functions, the first functions people will use), and
a ctf_setdebug()/ctf_getdebug() pair that allows the caller to
explicitly turn debugging off and on. If ctf_setdebug() is called,
the automatic setting from an environment variable is skipped.
libctf/
* ctf-impl.h: New file.
* ctf-subr.c: New file.
include/
* ctf-api.h (ctf_setdebug): New.
(ctf_getdebug): Likewise.
This non-installed header is the means by which libctf consumers
communicate with libctf.
This header will be extended in subsequent commits.
include/
* ctf-api.h: New file.
