Add max_log_level config option

Replaces --enable-debug-log

doc/migrate-4.rst

@@ -36,7 +36,7 @@ below shows corresponding Meson options:
 autotools                              meson
 ====================================== =====================================
 ``--enable-debug-symbols``             ``debug=true`` or ``buildtype=...``
-``--enable-debug-log``                 ``debug_log=true``
+``--enable-debug-log``                 ``max_log_level=debug``
 ``--enable-coverage``                  ``b_coverage=true``
 ``--disable-optimized``                ``optimization=0`` or ``buildtype=debug``
 ``--enable-lto``                       ``b_lto=true``
@@ -74,3 +74,12 @@ instead created as part of the build. This requires Python, with the
 
 An advantage of this approach is that it is now possible to directly build
 from a git checkout without any preparatory steps.
+
+Python configuration
+--------------------
+When building the Python bindings from source, it was previously only possible
+to adjust the build-time configuration by editing source files. With
+the new build system, it's now possible to `pass options`_ on the command
+line.
+
+.. _pass options: https://meson-python.readthedocs.io/en/latest/how-to-guides/config-settings.html

doc/py-logging.rst

@@ -2,9 +2,10 @@ Logging
 -------
 Logging is done with the standard Python :py:mod:`logging` module, and logging
 can be configured with the usual utilities. However, in the default build the
-debug logging is completely disabled for performance reasons [#]_. To enable
-it, add :samp:`-DSPEAD2_MAX_LOG_LEVEL=spead2::log_level::debug` to the compiler
-options in :file:`setup.py`.
+debug logging is completely disabled for performance reasons. To enable
+it, you need to set the Meson option ``max_log_level=debug``. For example, if
+installing with :command:`pip`, use
 
-.. [#] Logging is done from separate C threads, which have to wait for
-  Python's Global Interpreter Lock (GIL) in order to do logging.
+.. code:: sh
+
+   pip install --config-settings=setup-args=-Dmax_log_level=debug

include/spead2/common_features.h.in

@@ -62,4 +62,6 @@
 #define SPEAD2_USE_POSIX_SEMAPHORES @SPEAD2_USE_POSIX_SEMAPHORES@
 #define SPEAD2_USE_PCAP @SPEAD2_USE_PCAP@
 
+#define SPEAD2_MAX_LOG_LEVEL @SPEAD2_MAX_LOG_LEVEL@
+
 #endif // SPEAD2_COMMON_FEATURES_H

meson.build

@@ -211,6 +211,7 @@ conf.set10('SPEAD2_USE_PTHREAD_SETAFFINITY_NP', use_pthread_setaffinity_np)
 conf.set10('SPEAD2_USE_FMV', use_fmv)
 conf.set10('SPEAD2_USE_MOVNTDQ', use_movntdq)
 conf.set10('SPEAD2_USE_PCAP', pcap_dep.found())
+conf.set('SPEAD2_MAX_LOG_LEVEL', '(spead2::log_level::' + get_option('max_log_level') + ')')
 
 gen_loader = files('gen/gen_loader.py')
 gen_templates = files('gen/template.cpp', 'gen/template.h')

meson.options

@@ -31,5 +31,5 @@ option('gdrapi', type : 'feature', description : 'Build gdrcopy examples')
 option('unit_test', type : 'feature', description : 'Build the unit tests')
 
 option('python', type : 'boolean', value : false, description : 'Build Python bindings (for mesonpy; do not use directly)')
-option('debug_log', type : 'boolean', value : false, description : 'Generate debug log messages (slow)')
+option('max_log_level', type : 'combo', choices : ['debug', 'info', 'warning'], value : 'info', description : 'Generate debug log messages (slow)')
 option('python_split_debug', type : 'boolean', value : false, description : 'Split debug symbols into separate files (Python module only)')

src/meson.build

@@ -85,8 +85,6 @@ ssconfig = ss.apply(conf)
 
 # Targets
 
-# TODO: handle debug_log user option
-
 if not get_option('python')
   st_lib = static_library(
     'spead2',