Install in and use the correct libdir; and other compatibility fixes.

Ubuntu on 64 bits install lib in lib/x86_64-linux-gnu and meson correctly
detect this.
Thus it install libs (zimlib, kiwix) in this directory. However we
look for pkgconfig files in $INTALL_DIR/lib64. And so, the lib is not
found.

We could force meson to install in $INSTALL_DIR/lib64 all the time but
it is just better to follow the correct convention on Ubuntu.

Reuse the algorithm used in meson to correctly detect the libprefix,
use it and force all build script (autotools, cmake, meson) to install there.

In the same way, ninja may be called ninja-build depending of the distribution.
Or depending of how meson is installed, we may have to launch meson or meson.py.
So we detect the command to launch to try to be as most as possible portable.

scripts/kiwix-builder/kiwix-builder.py

@@ -1,10 +1,10 @@
 #!/usr/bin/env python3
 
-import os
+import os, sys
 import argparse
 import urllib.request
 import tarfile
-from subprocess import check_call, STDOUT, CalledProcessError
+import subprocess
 import hashlib
 import shutil
 from collections import defaultdict
@@ -21,6 +21,49 @@ ARCHIVE_DIR = pj(os.getcwd(), "ARCHIVE")
 ##### UTILS
 ################################################################################
 
+# Some utils taken from meson
+def is_debianlike():
+    return os.path.isfile('/etc/debian_version')
+
+
+def default_libdir():
+    if is_debianlike():
+        try:
+            pc = subprocess.Popen(['dpkg-architecture', '-qDEB_HOST_MULTIARCH'],
+                                  stdout=subprocess.PIPE,
+                                  stderr=subprocess.DEVNULL)
+            (stdo, _) = pc.communicate()
+            if pc.returncode == 0:
+                archpath = stdo.decode().strip()
+                return 'lib/' + archpath
+        except Exception:
+            pass
+    if os.path.isdir('/usr/lib64') and not os.path.islink('/usr/lib64'):
+        return 'lib64'
+    return 'lib'
+
+def detect_ninja():
+    for n in ['ninja', 'ninja-build']:
+        try:
+            retcode = subprocess.check_call([n, '--version'],
+                                            stdout=subprocess.DEVNULL)
+        except (FileNotFoundError, PermissionError):
+            # Doesn't exist in PATH or isn't executable
+            continue
+        if retcode == 0:
+            return n
+
+def detect_meson():
+    for n in ['meson.py', 'meson']:
+        try:
+            retcode = subprocess.check_call([n, '--version'],
+                                            stdout=subprocess.DEVNULL)
+        except (FileNotFoundError, PermissionError):
+            # Doesn't exist in PATH or isn't executable
+            continue
+        if retcode == 0:
+            return n
+
 class Defaultdict(defaultdict):
     def __getattr__(self, name):
         return self[name]
@@ -54,7 +97,7 @@ def command(name, withlog='source_path', autoskip=False):
                 return ret
             except SkipCommand:
                 print("SKIP")
-            except CalledProcessError:
+            except subprocess.CalledProcessError:
                 print("ERROR")
                 with open(log, 'r') as f:
                     print(f.read())
@@ -78,7 +121,7 @@ def run_command(command, cwd, log, env=None, input=None):
         kwargs['env'] = env
     if input:
         kwargs['stdin'] = input
-    return check_call(command, shell=True, cwd=cwd, stdout=log, stderr=STDOUT, **kwargs)
+    return subprocess.check_call(command, shell=True, cwd=cwd, stdout=log, stderr=subprocess.STDOUT, **kwargs)
 
 
 
@@ -175,7 +218,13 @@ class MakeMixin:
 
     @command("configure", autoskip=True)
     def _configure(self, options, log):
-        command = self.configure_script + " " + self.configure_option + " --prefix " + options.install_dir
+        command = "{configure_script} {configure_option} --prefix {install_dir} --libdir {libdir}"
+        command = command.format(
+            configure_script = self.configure_script,
+            configure_option = self.configure_option,
+            install_dir = options.install_dir,
+            libdir = pj(options.install_dir, options.libprefix)
+        )
         env = Defaultdict(str, os.environ)
         if options.build_static:
             env['CFLAGS'] = env['CFLAGS'] + ' -fPIC'
@@ -207,14 +256,27 @@ class MakeMixin:
 class CMakeMixin(MakeMixin):
     @command("configure", autoskip=True)
     def _configure(self, options, log):
-        libdir = "-DCMAKE_INSTALL_LIBDIR={}".format("lib64" if options.target_arch == "x86_64" else "lib")
+        command = "cmake {configure_option} -DCMAKE_INSTALL_PREFIX={install_dir} -DCMAKE_INSTALL_LIBDIR={libdir}"
-        command = "cmake {configure_option} -DCMAKE_INSTALL_PREFIX={install_dir} {extra_options}".format(
+        command = command.format(
             configure_option = self.configure_option,
             install_dir = options.install_dir,
-            extra_options = libdir)
+            libdir = options.libprefix
-        run_command(command, self.source_path, log)
+        )
+        env = Defaultdict(str, os.environ)
+        if options.build_static:
+            env['CFLAGS'] = env['CFLAGS'] + ' -fPIC'
+        if self.configure_env:
+           for k in self.configure_env:
+               if k.startswith('_format_'):
+                   v = self.configure_env.pop(k)
+                   v = v.format(options=options, env=env)
+                   self.configure_env[k[8:]] = v
+           env.update(self.configure_env)
+        run_command(command, self.source_path, log, env=env)
 
 class MesonMixin(MakeMixin):
+    meson_command = detect_meson()
+    ninja_command = detect_ninja()
     @property
     def build_path(self):
         return pj(self.source_path, 'build')
@@ -225,15 +287,18 @@ class MesonMixin(MakeMixin):
             shutil.rmtree(self.build_path)
         os.makedirs(self.build_path)
         env = Defaultdict(str, os.environ)
-        env['PKG_CONFIG_PATH'] = ':'.join([pj(options.install_dir, 'lib64', 'pkgconfig'),
+        env['PKG_CONFIG_PATH'] = (env['PKG_CONFIG_PATH'] + ':' + pj(options.install_dir, options.libprefix, 'pkgconfig')
-                                          pj(options.install_dir, 'lib', 'pkgconfig')])
+                                  if env['PKG_CONFIG_PATH']
+                                  else pj(options.install_dir, options.libprefix, 'pkgconfig')
+                                 )
         if options.build_static:
             env['LDFLAGS'] = env['LDFLAGS'] + " -static-libstdc++ --static"
             library_type = 'static'
         else:
             library_type = 'shared'
         configure_option = self.configure_option.format(options=options)
-        command = "meson.py --default-library={library_type} {configure_option} . build --prefix={options.install_dir}".format(
+        command = "{command} --default-library={library_type} {configure_option} . build --prefix={options.install_dir} --libdir={options.libprefix}".format(
+            command = self.meson_command,
             library_type=library_type,
             configure_option=configure_option,
             options=options)
@@ -241,11 +306,13 @@ class MesonMixin(MakeMixin):
 
     @command("compile")
     def _compile(self, log):
-        run_command("ninja-build -v", self.build_path, log)
+        command = "{} -v".format(self.ninja_command)
+        run_command(command, self.build_path, log)
 
     @command("install")
     def _install(self, log):
-        run_command("ninja-build -v install", self.build_path, log)
+        command = "{} -v install".format(self.ninja_command)
+        run_command(command, self.build_path, log)
 
 
 # *************************************
@@ -290,7 +357,7 @@ class Xapian(Dependency, ReleaseDownloadMixin, MakeMixin):
     archive_sha256 = '10584f57112aa5e9c0e8a89e251aecbf7c582097638bfee79c1fe39a8b6a6477'
     configure_option = "--enable-shared --enable-static --disable-sse --disable-backend-inmemory"
     patch = "xapian_pkgconfig.patch"
-    configure_env = {'_format_LDFLAGS' : "-L{options.install_dir}/lib",
+    configure_env = {'_format_LDFLAGS' : "-L{options.install_dir}/{options.libprefix}",
                      '_format_CXXFLAGS' : "-I{options.install_dir}/include"}
 
 
@@ -401,6 +468,7 @@ class Project:
 def parse_args():
     parser = argparse.ArgumentParser()
     parser.add_argument('install_dir')
+    parser.add_argument('--libprefix', default=default_libdir())
     parser.add_argument('--target_arch', default="x86_64")
     parser.add_argument('--build_static', action="store_true")
     return parser.parse_args()