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
