meson: Improve library detection

[madpilot78]

Fix detection of some libraries in FreeBSD

• Use pkgconfig to detect faad (using faad2.pc)
• Look for mp3lame and lirc_client in /usr/local/lib on FreeBSD
• Remove unneeded link_args: ['-llirc_client'], required arguments provided by cxx.find_library()

[radioactiveman]

1. This has nothing to do with libintl, you only copy-pasted the description from your other pull request.
2. Is the correct name lirc or lirc_client?
3. Could we use pkgconfig (using dependency() instead of cxx.find_library() on FreeBSD? I don't like workarounds like these and would prefer a general solution. If needed with a fallback to the current approach to support older distributions.
4. The filewriter plugin also uses cxx.find_library() to search lame. Does this work on FreeBSD?

[madpilot78]

@radioactiveman

1. This has nothing to do with libintl, you only copy-pasted the description from your other pull request.

Ops sorry, I prepared the commit messages in a separate editor, and must have pasted the wrong text there. I'll fix it later while rebasing this patch.

2. Is the correct name `lirc` or `lirc_client`?

In FreeBSD the library is installed as /usr/local/lib/liblirc_client.so by default. so I guess correct one is lirc_client. I think this is due to the library providing only client utilities.

3. Could we use `pkgconfig` (using `dependency()` instead of `cxx.find_library()` on FreeBSD? I don't like workarounds like these and would prefer a general solution. If needed with a fallback to the current approach to support older distributions.

In this case I used cxx.find_library() since that was what was being used, I can change my patch easily.

As far as I can see lirc_client does not provide a .pc file, so it cannot be detected via pkgconfig.

OTOH faad does provide a .pc file, so I can use dependency() for that.

4. The `filewriter` plugin also uses `cxx.find_library()` to search `lame`. Does this work on FreeBSD?

I admit I did not check this, and it is actually failing to find it, so I will also fix this one.

This library is also not providing a .pc file, so I will need to keep using cxx.find_library().

I'll rebase this patch adding the required fixes.

Thanks for you feedback!

[madpilot78]

Regarding faad, I guess the patch can be generalized and the same detection used for all OSes. I'm unable to test this properly though.

[radioactiveman]

I have checked the packages on Arch Linux. All of them (faad2, LIRC, lame) ship a pkgconfig file.

My idea was to use an approach like shown below. First search with pkgconfig, then with find_library() as fallback. The dirs parameter can be passed generally. The default dir (like /usr/lib) is then still searched. And the header check can also be included here since we require Meson 0.51 meanwhile.

See also: https://mesonbuild.com/Reference-manual_returned_compiler.html#compilerfind_library

Would you do this for all three libraries? Also include a "meson: " prefix in the commit message. Thanks.
Please test on FreeBSD, our CI does the rest. 😃

diff --git a/src/lirc/meson.build b/src/lirc/meson.build
index 9d214bb31..475f8b00d 100644
--- a/src/lirc/meson.build
+++ b/src/lirc/meson.build
@@ -1,13 +1,17 @@
-lirc_dep = cxx.find_library('lirc', required: false)
-have_lirc = lirc_dep.found() and cxx.has_header('lirc/lirc_client.h')
+lirc_dep = dependency('lirc', required: false)
 
+if not lirc_dep.found()
+  lirc_dep = cxx.find_library('lirc_client', has_headers: 'lirc/lirc_client.h',
+                              dirs: ['/usr/local/lib'], required: false)
+endif
+
+have_lirc = lirc_dep.found()
 
 if have_lirc
   shared_module('lirc',
     'lirc.cc',
     dependencies: [audacious_dep, glib_dep, lirc_dep],
     name_prefix: '',
-    link_args: ['-llirc_client'],
     install: true,
     install_dir: general_plugin_dir
   )

[madpilot78]

@radioactiveman Good idea!

As far as I can see the lirc project distribution itself does not include a pc file, and the FreeBSD port is not adding one.

Anyway, sure I'll update the patch with the suggested behavior.

[radioactiveman]

1. The pkgconfig name is lame, not mp3lame.
2. Nit-pick but I would add an empty line between the endif and have_[aac,lirc]. 😉
3. Meson supports LIBRARY_PATH. Does this work for you on FreeBSD?
   Removing the dirs: ['/usr/local/lib'] parameters again would fix the failing Windows CI build.

export LIBRARY_PATH=/usr/local/lib
meson setup build
meson compile -C build

[jlindgren90]

I would much prefer the LIBRARY_PATH approach if that works. Hard-coding /usr/local in a bunch of places seems wrong.

[madpilot78]

1. The pkgconfig name is lame, not mp3lame.

I was not aware of this. I'll change that.

2. Nit-pick but I would add an empty line between the `endif` and `have_[aac,lirc]`. wink

✅

3. Meson supports `LIBRARY_PATH`. Does this work for you on FreeBSD?
   Removing the `dirs: ['/usr/local/lib']` parameters again would fix the failing Windows CI build.

export LIBRARY_PATH=/usr/local/lib
meson setup build
meson compile -C build

Should work in FreeBSD, I need to do some testing though, but it does look cleaner on my side too, since, in the FreeBSD ports tree, /usr/local/can be changed by the user a t build time and I have been using substitutions for now.

I'll also update audacious-media-player/audacious#60 ro use LIBRARY_PATH if it works.

[madpilot78]

@radioactiveman @jlindgren90

I confirm using LIBRARY_PATH works fine for me, so I have updated the patch.

[jlindgren90]

Assuming CI passes, this looks good to me.

[radioactiveman]

Pushed as bf40a4b with minor clean-ups. Thanks again @madpilot78 for your contribution.