[ANDROID] Deactivate some features if we are compiling for android.

Android libc doesn't support all thread feature (as pthread_cancel).
Do not compile those files if we are compiling for android.

include/meson.build

@@ -1,11 +1,14 @@
 headers = [
-  'indexer.h',
   'library.h',
   'manager.h',
   'reader.h',
   'searcher.h'
 ]
 
+if not get_option('android')
+  headers += ['indexer.h']
+endif
+
 if xapian_dep.found()
   headers += ['xapianIndexer.h', 'xapianSearcher.h']
 endif

meson_options.txt

@@ -1,2 +1,4 @@
 option('ctpp2-install-prefix', type : 'string', value : '',
   description : 'Prefix where ctpp libs has been installed')
+option('android', type : 'boolean', value : false,
+  description : 'Do we make a kiwix-lib for android')

src/meson.build

@@ -3,7 +3,6 @@ kiwix_sources = [
   'manager.cpp',
   'reader.cpp',
   'searcher.cpp',
-  'indexer.cpp',
   'common/base64.cpp',
   'common/pathTools.cpp',
   'common/regexTools.cpp',
@@ -16,7 +15,14 @@ kiwix_sources = [
 kiwix_sources += lib_resources
 
 if xapian_dep.found()
-  kiwix_sources += ['xapianIndexer.cpp', 'xapianSearcher.cpp']
+  kiwix_sources += ['xapianSearcher.cpp']
+  if not get_option('android')
+    kiwix_sources += ['xapianIndexer.cpp']
+  endif
+endif
+
+if not get_option('android')
+  kiwix_sources += ['indexer.cpp']
 endif
 
 if has_ctpp2_dep