NM_API_VERSION is a better name. It's not the current stable
version, but the version number of the API which the current
NM_VERSION provides. In practice, NM_API_VERSION is either identical
to NM_VERSION (in case of a release) or NM_VERSION is a development
version leading up the the upcoming NM_API_VERSION.
For example, with the new name the check
#if NM_VERSION != NM_API_VERSION
# warning this is an development version
#endif
makes more sense.
We don't need to have two version defines "CUR" and "NEXT".
The main purpose of these macros (if not their only), is to
make NM_AVAILABLE_IN_* and NM_DEPRECATED_IN_* macros work.
1) At the precise commit of a release, "CUR" and "NEXT" must be identical,
because whenever the user configures NM_VERSION_MIN_REQUIRED and
NM_VERSION_MAX_ALLOWED, then they both compare against the current
version, at which point "CUR" == "NEXT".
2) Every other commit aside the release, is a development version that leads
up the the next coming release. But as far as versioning is concerned, such
a development version should be treated like that future release. It's unstable
API and it may or may not be close to later API of the release. But
we shall treat it as that version. Hence, also in this case, we want to
set both "NM_VERSION_CUR_STABLE" and again NEXT to the future version.
This makes NM_VERSION_NEXT_STABLE redundant.
Previously, the separation between current and next version would for
example allow that NM_VERSION_CUR_STABLE is the previously release
stable API, and NM_VERSION_NEXT_STABLE is the version of the next upcoming
stable API. So, we could allow "examples" to make use of development
API, but other(?) internal code still restrict to unstable API. But it's
unclear which other code would want to avoid current development.
Also, the points 1) and 2) were badly understood. Note that for our
previousy releases, we usually didn't bump the macros at the stable
release (and if we did, we didn't set them to be the same). While using
two macros might be more powerful, it is hard to grok and easy to
forget to bump the macros a the right time. One macro shall suffice.
All this also means, that *immediately* after making a new release, we shall
bump the version number in `configure.ac` and "NM_VERSION_CUR_STABLE".
In practice, this should only matter when there are multiple
header files with the same name. That is something we try
to avoid already, by giving headers a distinct name.
When building NetworkManager itself, we clearly want to use
double-quotes for including our own headers.
But we also want to do that in our public headers. For example:
./a.c
#include <stdio.h>
#include <nm-1.h>
void main() {
printf ("INCLUDED %s/nm-2.h\n", SYMB);
}
./1/nm-1.h
#include <nm-2.h>
./1/nm-2.h
#define SYMB "1"
./2/nm-2.h
#define SYMB "2"
$ cc -I./2 -I./1 ./a.c
$ ./a.out
INCLUDED 2/nm-2.h
Exceptions to this are
- headers in "shared/nm-utils" that include <NetworkManager.h>. These
headers are copied into projects and hence used like headers owned by
those projects.
- examples/C
For libnm library, "nm-dbus-interface.h" contains defines like the D-Bus
paths of NetworkManager. It is desirable to have this header usable without
having a dependency on "glib.h", for example for a QT application. For that,
commit c0852964a8 removed that dependancy.
For libnm-glib library, the analog to "nm-dbus-interface.h" is
"NetworkManager.h", and the same applies there. Commit
159e827a72 removed that include.
However, that broke build on PackageKit [1] which expected to get the
version macros by including "NetworkManager.h". So at least for libnm-glib,
we need to preserve old behavior so that a user including
"NetworkManager.h" gets the version macros, but not "glib.h".
Extract the version macros to a new header file "nm-version-macros.h".
This header doesn't include "glib.h" and can be included from
"NetworkManager.h". This gives as previous behavior and a glib-free
include.
For libnm we still don't include "nm-version-macros.h" to "nm-dbus-interface.h".
Very few users will actually need the version macros, but not using
libnm.
Users that use libnm, should just include (libnm's) "NetworkManager.h" to
get all headers.
As a special case, a user who doesn't want to use glib/libnm, but still
needs both "nm-dbus-interface.h" and "nm-version-macros.h", can include
them both separately.
[1] https://github.com/hughsie/PackageKit/issues/85
Fixes: 4545a7fe96
2015-09-30 23:10:29 +02:00
Renamed from libnm-core/nm-version.h.in (Browse further)
