There are certain cases where we may not want to display the entire
header for a given set of properties. For example displaying a list
of proxy interfaces. Add finer control by separating out the header
and the prop/value display into two functions.
The generic proxy property display was limited to a width for names/value
which makes the output look nice and uniform, but will cut off any values
which are longer than this limit.
This patch adds some logic to detect this, and continue displaying the
value on the next line.
The width arguments were also updated to be unsigned, which allows checking
the length without a cast.
LLD 13 and GNU ld 2.37 support -z start-stop-gc which allows garbage
collection of C identifier name sections despite the __start_/__stop_
references. GNU ld before 2015-10 had the behavior as well. Simply set
the retain attribute so that GCC 11 (if configure-time binutils is 2.36
or newer)/Clang 13 will set the SHF_GNU_RETAIN section attribute to
prevent garbage collection.
Without the patch, there are linker errors with -z start-stop-gc
(LLD default) when -Wl,--gc-sections is used:
```
ld.lld: error: undefined symbol: __start___eap
>>> referenced by eap.c
>>> src/eap.o:(eap_init)
```
The remain attribute will not be needed if the metadata sections are
referenced by code directly.
This function now takes an extra argument 'extra_interface'. When
non-NULL, the property match is furthered filtered by checking whether
the proxy_interface on the given path also contains an interface of type
'extra_interface'
