meson: generate Doxygen documentation

Run 'meson compile doc'

doc/doxygen.conf.in

@@ -933,7 +933,7 @@ WARN_LOGFILE           =
 # spaces. See also FILE_PATTERNS and EXTENSION_MAPPING
 # Note: If this tag is empty the current directory is searched.
 
-INPUT                  = src
+INPUT                  = ../src pcsclite.h
 
 # This tag can be used to specify the character encoding of the source files
 # that doxygen parses. Internally doxygen uses the UTF-8 encoding. Doxygen uses

meson.build

@@ -271,3 +271,15 @@ pkg.generate(
     'usbdropdir=' + conf_data.get_unquoted('PCSCLITE_HP_DROPDIR'),
     'serialconfdir=' + get_option('serialconfdir')],
   description : 'PC/SC smart card interface')
+
+# generate documentation
+configure_file(output : 'doxygen.conf',
+  input : 'doc/doxygen.conf.in',
+  configuration : confgen_data)
+doxygen = find_program('doxygen', required : false)
+if doxygen.found()
+  message('Doxygen found')
+  run_target('doc', command : [doxygen, 'doxygen.conf'])
+else
+  warning('Documentation disabled without doxygen')
+endif