external-project: Add support for WAF build system

Fixes: #7638

4 files changed, 53 insertions, 27 deletions

diff --git a/docs/markdown/External-Project-module.md b/docs/markdown/External-Project-module.md
index 866564e..640caaf 100644
--- a/docs/markdown/External-Project-module.md
+++ b/docs/markdown/External-Project-module.md
@@ -63,6 +63,10 @@ directory and executable. Note that if a bootstrap script is required
 (e.g. `autogen.sh` when building from git instead of tarball), it can
 be done using `run_command()` before calling `add_project()` method.
 
+*Since 0.60.0* If the first positional argument is `'waf'`, special treatment
+is done for the [waf](https://waf.io/) build system. The waf executable must be
+found either in the current directory, or in system `PATH`.
+
 Keyword arguments:
 
 - `configure_options`: An array of strings to be passed as arguments to the
diff --git a/docs/markdown/snippets/waf.md b/docs/markdown/snippets/waf.md
new file mode 100644
index 0000000..87634a0
--- /dev/null
+++ b/docs/markdown/snippets/waf.md
@@ -0,0 +1,5 @@
+## Waf support in external-project module
+
+If the first argument is `'waf'`, special treatment is done for the
+[waf](https://waf.io/) build system. The waf executable must be
+found either in the current directory, or in system `PATH`.
diff --git a/mesonbuild/modules/unstable_external_project.py b/mesonbuild/modules/unstable_external_project.py
index f866e75..32ecdf9 100644
--- a/mesonbuild/modules/unstable_external_project.py
+++ b/mesonbuild/modules/unstable_external_project.py
@@ -19,7 +19,7 @@ import typing as T
 from . import ExtensionModule, ModuleReturnValue, ModuleState, NewExtensionModule
 from .. import mlog, build
 from ..mesonlib import (MesonException, Popen_safe, MachineChoice,
-                       get_variable_regex, do_replacement, extract_as_list)
+                       get_variable_regex, do_replacement, extract_as_list, join_args)
 from ..interpreterbase import InterpreterException, FeatureNew
 from ..interpreterbase import permittedKwargs, typed_pos_args
 from ..compilers.compilers import CFLAGS_MAPPING, CEXE_MAPPING
@@ -67,19 +67,26 @@ class ExternalProject(NewExtensionModule):
         # self.prefix is an absolute path, so we cannot append it to another path.
         self.rel_prefix = self.prefix.relative_to(self.prefix.root)
 
-        self.make = state.find_program('make')
-        self.make = self.make.get_command()[0]
-
         self._configure(state)
 
         self.targets = self._create_targets()
 
     def _configure(self, state: ModuleState):
-        # Assume it's the name of a script in source dir, like 'configure',
-        # 'autogen.sh', etc).
-        configure_path = Path(self.src_dir, self.configure_command)
-        configure_prog = state.find_program(configure_path.as_posix())
-        configure_cmd = configure_prog.get_command()
+        if self.configure_command == 'waf':
+            FeatureNew('Waf external project', '0.60.0').use(self.subproject)
+            waf = state.find_program('waf')
+            configure_cmd = waf.get_command()
+            configure_cmd += ['configure', '-o', str(self.build_dir)]
+            workdir = self.src_dir
+            self.make = waf.get_command() + ['build']
+        else:
+            # Assume it's the name of a script in source dir, like 'configure',
+            # 'autogen.sh', etc).
+            configure_path = Path(self.src_dir, self.configure_command)
+            configure_prog = state.find_program(configure_path.as_posix())
+            configure_cmd = configure_prog.get_command()
+            workdir = self.build_dir
+            self.make = state.find_program('make').get_command()
 
         d = [('PREFIX', '--prefix=@PREFIX@', self.prefix.as_posix()),
              ('LIBDIR', '--libdir=@PREFIX@/@LIBDIR@', self.libdir.as_posix()),
@@ -122,7 +129,7 @@ class ExternalProject(NewExtensionModule):
                                       Path(self.env.get_build_dir(), 'meson-uninstalled').as_posix())
 
         self.build_dir.mkdir(parents=True, exist_ok=True)
-        self._run('configure', configure_cmd)
+        self._run('configure', configure_cmd, workdir)
 
     def _quote_and_join(self, array: T.List[str]) -> str:
         return ' '.join([shlex.quote(i) for i in array])
@@ -156,9 +163,9 @@ class ExternalProject(NewExtensionModule):
                 f"Variables {var_list} in configure options are missing.")
         return out
 
-    def _run(self, step: str, command: T.List[str]):
+    def _run(self, step: str, command: T.List[str], workdir: Path):
         mlog.log(f'External project {self.name}:', mlog.bold(step))
-        m = 'Running command ' + str(command) + ' in directory ' + str(self.build_dir) + '\n'
+        m = 'Running command ' + str(command) + ' in directory ' + str(workdir) + '\n'
         log_filename = Path(mlog.log_dir, f'{self.name}-{step}.log')
         output = None
         if not self.verbose:
@@ -167,9 +174,9 @@ class ExternalProject(NewExtensionModule):
             output.flush()
         else:
             mlog.log(m)
-        p, o, e = Popen_safe(command, cwd=str(self.build_dir), env=self.run_env,
-                                      stderr=subprocess.STDOUT,
-                                      stdout=output)
+        p, o, e = Popen_safe(command, cwd=str(workdir), env=self.run_env,
+                             stderr=subprocess.STDOUT,
+                             stdout=output)
         if p.returncode != 0:
             m = f'{step} step returned error code {p.returncode}.'
             if not self.verbose:
@@ -184,7 +191,7 @@ class ExternalProject(NewExtensionModule):
                 '--builddir', self.build_dir.as_posix(),
                 '--installdir', self.install_dir.as_posix(),
                 '--logdir', mlog.log_dir,
-                '--make', self.make,
+                '--make', join_args(self.make),
                 ]
         if self.verbose:
             cmd.append('--verbose')
diff --git a/mesonbuild/scripts/externalproject.py b/mesonbuild/scripts/externalproject.py
index a8e3bfe..eefa32e 100644
--- a/mesonbuild/scripts/externalproject.py
+++ b/mesonbuild/scripts/externalproject.py
@@ -19,7 +19,7 @@ import subprocess
 from pathlib import Path
 import typing as T
 
-from ..mesonlib import Popen_safe
+from ..mesonlib import Popen_safe, split_args
 
 class ExternalProject:
     def __init__(self, options: argparse.Namespace):
@@ -31,7 +31,7 @@ class ExternalProject:
         self.verbose = options.verbose
         self.stampfile = options.stampfile
         self.depfile = options.depfile
-        self.make = options.make
+        self.make = split_args(options.make)
 
     def write_depfile(self) -> None:
         with open(self.depfile, 'w', encoding='utf-8') as f:
@@ -49,22 +49,28 @@ class ExternalProject:
             pass
 
     def gnu_make(self) -> bool:
-        p, o, e = Popen_safe([self.make, '--version'])
+        p, o, e = Popen_safe(self.make + ['--version'])
         if p.returncode == 0 and 'GNU Make' in o:
             return True
         return False
 
     def build(self) -> int:
-        make_cmd = [self.make]
-        if self.gnu_make():
-            make_cmd.append('-j' + str(multiprocessing.cpu_count()))
-
+        is_make = self.make[0] == 'make'
+        make_cmd = self.make.copy()
+        if is_make and self.gnu_make():
+            make_cmd.append(f'-j{multiprocessing.cpu_count()}')
         rc = self._run('build', make_cmd)
         if rc != 0:
             return rc
 
-        install_cmd = make_cmd + ['DESTDIR= ' + self.install_dir, 'install']
-        rc = self._run('install', install_cmd)
+        install_cmd = self.make.copy()
+        install_env = {}
+        if is_make:
+            install_cmd.append(f'DESTDIR={self.install_dir}')
+        else:
+            install_env['DESTDIR'] = self.install_dir
+        install_cmd.append('install')
+        rc = self._run('install', install_cmd, install_env)
         if rc != 0:
             return rc
 
@@ -73,7 +79,7 @@ class ExternalProject:
 
         return 0
 
-    def _run(self, step: str, command: T.List[str]) -> int:
+    def _run(self, step: str, command: T.List[str], env: T.Optional[T.Dict[str, str]] = None) -> int:
         m = 'Running command ' + str(command) + ' in directory ' + str(self.build_dir) + '\n'
         log_filename = Path(self.log_dir, f'{self.name}-{step}.log')
         output = None
@@ -83,8 +89,12 @@ class ExternalProject:
             output.flush()
         else:
             print(m)
+        run_env = os.environ.copy()
+        if env:
+            run_env.update(env)
         p, o, e = Popen_safe(command, stderr=subprocess.STDOUT, stdout=output,
-                             cwd=self.build_dir)
+                             cwd=self.build_dir,
+                             env=run_env)
         if p.returncode != 0:
             m = f'{step} step returned error code {p.returncode}.'
             if not self.verbose: